| File: | src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Analysis/ValueTracking.h |
| Warning: | line 282, column 49 Called C++ object pointer is null |
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| 1 | //===- AttributorAttributes.cpp - Attributes for Attributor deduction -----===// | ||||||||
| 2 | // | ||||||||
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | ||||||||
| 4 | // See https://llvm.org/LICENSE.txt for license information. | ||||||||
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | ||||||||
| 6 | // | ||||||||
| 7 | //===----------------------------------------------------------------------===// | ||||||||
| 8 | // | ||||||||
| 9 | // See the Attributor.h file comment and the class descriptions in that file for | ||||||||
| 10 | // more information. | ||||||||
| 11 | // | ||||||||
| 12 | //===----------------------------------------------------------------------===// | ||||||||
| 13 | |||||||||
| 14 | #include "llvm/Transforms/IPO/Attributor.h" | ||||||||
| 15 | |||||||||
| 16 | #include "llvm/ADT/APInt.h" | ||||||||
| 17 | #include "llvm/ADT/SCCIterator.h" | ||||||||
| 18 | #include "llvm/ADT/SmallPtrSet.h" | ||||||||
| 19 | #include "llvm/ADT/Statistic.h" | ||||||||
| 20 | #include "llvm/Analysis/AliasAnalysis.h" | ||||||||
| 21 | #include "llvm/Analysis/AssumeBundleQueries.h" | ||||||||
| 22 | #include "llvm/Analysis/AssumptionCache.h" | ||||||||
| 23 | #include "llvm/Analysis/CaptureTracking.h" | ||||||||
| 24 | #include "llvm/Analysis/InstructionSimplify.h" | ||||||||
| 25 | #include "llvm/Analysis/LazyValueInfo.h" | ||||||||
| 26 | #include "llvm/Analysis/MemoryBuiltins.h" | ||||||||
| 27 | #include "llvm/Analysis/OptimizationRemarkEmitter.h" | ||||||||
| 28 | #include "llvm/Analysis/ScalarEvolution.h" | ||||||||
| 29 | #include "llvm/Analysis/TargetTransformInfo.h" | ||||||||
| 30 | #include "llvm/Analysis/ValueTracking.h" | ||||||||
| 31 | #include "llvm/IR/Constants.h" | ||||||||
| 32 | #include "llvm/IR/IRBuilder.h" | ||||||||
| 33 | #include "llvm/IR/Instruction.h" | ||||||||
| 34 | #include "llvm/IR/Instructions.h" | ||||||||
| 35 | #include "llvm/IR/IntrinsicInst.h" | ||||||||
| 36 | #include "llvm/IR/NoFolder.h" | ||||||||
| 37 | #include "llvm/Support/Alignment.h" | ||||||||
| 38 | #include "llvm/Support/Casting.h" | ||||||||
| 39 | #include "llvm/Support/CommandLine.h" | ||||||||
| 40 | #include "llvm/Support/ErrorHandling.h" | ||||||||
| 41 | #include "llvm/Support/FileSystem.h" | ||||||||
| 42 | #include "llvm/Support/raw_ostream.h" | ||||||||
| 43 | #include "llvm/Transforms/IPO/ArgumentPromotion.h" | ||||||||
| 44 | #include "llvm/Transforms/Utils/Local.h" | ||||||||
| 45 | #include <cassert> | ||||||||
| 46 | |||||||||
| 47 | using namespace llvm; | ||||||||
| 48 | |||||||||
| 49 | #define DEBUG_TYPE"attributor" "attributor" | ||||||||
| 50 | |||||||||
| 51 | static cl::opt<bool> ManifestInternal( | ||||||||
| 52 | "attributor-manifest-internal", cl::Hidden, | ||||||||
| 53 | cl::desc("Manifest Attributor internal string attributes."), | ||||||||
| 54 | cl::init(false)); | ||||||||
| 55 | |||||||||
| 56 | static cl::opt<int> MaxHeapToStackSize("max-heap-to-stack-size", cl::init(128), | ||||||||
| 57 | cl::Hidden); | ||||||||
| 58 | |||||||||
| 59 | template <> | ||||||||
| 60 | unsigned llvm::PotentialConstantIntValuesState::MaxPotentialValues = 0; | ||||||||
| 61 | |||||||||
| 62 | static cl::opt<unsigned, true> MaxPotentialValues( | ||||||||
| 63 | "attributor-max-potential-values", cl::Hidden, | ||||||||
| 64 | cl::desc("Maximum number of potential values to be " | ||||||||
| 65 | "tracked for each position."), | ||||||||
| 66 | cl::location(llvm::PotentialConstantIntValuesState::MaxPotentialValues), | ||||||||
| 67 | cl::init(7)); | ||||||||
| 68 | |||||||||
| 69 | STATISTIC(NumAAs, "Number of abstract attributes created")static llvm::Statistic NumAAs = {"attributor", "NumAAs", "Number of abstract attributes created" }; | ||||||||
| 70 | |||||||||
| 71 | // Some helper macros to deal with statistics tracking. | ||||||||
| 72 | // | ||||||||
| 73 | // Usage: | ||||||||
| 74 | // For simple IR attribute tracking overload trackStatistics in the abstract | ||||||||
| 75 | // attribute and choose the right STATS_DECLTRACK_********* macro, | ||||||||
| 76 | // e.g.,: | ||||||||
| 77 | // void trackStatistics() const override { | ||||||||
| 78 | // STATS_DECLTRACK_ARG_ATTR(returned) | ||||||||
| 79 | // } | ||||||||
| 80 | // If there is a single "increment" side one can use the macro | ||||||||
| 81 | // STATS_DECLTRACK with a custom message. If there are multiple increment | ||||||||
| 82 | // sides, STATS_DECL and STATS_TRACK can also be used separately. | ||||||||
| 83 | // | ||||||||
| 84 | #define BUILD_STAT_MSG_IR_ATTR(TYPE, NAME)("Number of " "TYPE" " marked '" "NAME" "'") \ | ||||||||
| 85 | ("Number of " #TYPE " marked '" #NAME "'") | ||||||||
| 86 | #define BUILD_STAT_NAME(NAME, TYPE)NumIRTYPE_NAME NumIR##TYPE##_##NAME | ||||||||
| 87 | #define STATS_DECL_(NAME, MSG)static llvm::Statistic NAME = {"attributor", "NAME", MSG}; STATISTIC(NAME, MSG)static llvm::Statistic NAME = {"attributor", "NAME", MSG}; | ||||||||
| 88 | #define STATS_DECL(NAME, TYPE, MSG)static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; \ | ||||||||
| 89 | STATS_DECL_(BUILD_STAT_NAME(NAME, TYPE), MSG)static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; | ||||||||
| 90 | #define STATS_TRACK(NAME, TYPE)++(NumIRTYPE_NAME); ++(BUILD_STAT_NAME(NAME, TYPE)NumIRTYPE_NAME); | ||||||||
| 91 | #define STATS_DECLTRACK(NAME, TYPE, MSG){ static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; ++(NumIRTYPE_NAME); } \ | ||||||||
| 92 | { \ | ||||||||
| 93 | STATS_DECL(NAME, TYPE, MSG)static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; \ | ||||||||
| 94 | STATS_TRACK(NAME, TYPE)++(NumIRTYPE_NAME); \ | ||||||||
| 95 | } | ||||||||
| 96 | #define STATS_DECLTRACK_ARG_ATTR(NAME){ static llvm::Statistic NumIRArguments_NAME = {"attributor", "NumIRArguments_NAME", ("Number of " "arguments" " marked '" "NAME" "'")};; ++(NumIRArguments_NAME); } \ | ||||||||
| 97 | STATS_DECLTRACK(NAME, Arguments, BUILD_STAT_MSG_IR_ATTR(arguments, NAME)){ static llvm::Statistic NumIRArguments_NAME = {"attributor", "NumIRArguments_NAME", ("Number of " "arguments" " marked '" "NAME" "'")};; ++(NumIRArguments_NAME); } | ||||||||
| 98 | #define STATS_DECLTRACK_CSARG_ATTR(NAME){ static llvm::Statistic NumIRCSArguments_NAME = {"attributor" , "NumIRCSArguments_NAME", ("Number of " "call site arguments" " marked '" "NAME" "'")};; ++(NumIRCSArguments_NAME); } \ | ||||||||
| 99 | STATS_DECLTRACK(NAME, CSArguments, \{ static llvm::Statistic NumIRCSArguments_NAME = {"attributor" , "NumIRCSArguments_NAME", ("Number of " "call site arguments" " marked '" "NAME" "'")};; ++(NumIRCSArguments_NAME); } | ||||||||
| 100 | BUILD_STAT_MSG_IR_ATTR(call site arguments, NAME)){ static llvm::Statistic NumIRCSArguments_NAME = {"attributor" , "NumIRCSArguments_NAME", ("Number of " "call site arguments" " marked '" "NAME" "'")};; ++(NumIRCSArguments_NAME); } | ||||||||
| 101 | #define STATS_DECLTRACK_FN_ATTR(NAME){ static llvm::Statistic NumIRFunction_NAME = {"attributor", "NumIRFunction_NAME" , ("Number of " "functions" " marked '" "NAME" "'")};; ++(NumIRFunction_NAME ); } \ | ||||||||
| 102 | STATS_DECLTRACK(NAME, Function, BUILD_STAT_MSG_IR_ATTR(functions, NAME)){ static llvm::Statistic NumIRFunction_NAME = {"attributor", "NumIRFunction_NAME" , ("Number of " "functions" " marked '" "NAME" "'")};; ++(NumIRFunction_NAME ); } | ||||||||
| 103 | #define STATS_DECLTRACK_CS_ATTR(NAME){ static llvm::Statistic NumIRCS_NAME = {"attributor", "NumIRCS_NAME" , ("Number of " "call site" " marked '" "NAME" "'")};; ++(NumIRCS_NAME ); } \ | ||||||||
| 104 | STATS_DECLTRACK(NAME, CS, BUILD_STAT_MSG_IR_ATTR(call site, NAME)){ static llvm::Statistic NumIRCS_NAME = {"attributor", "NumIRCS_NAME" , ("Number of " "call site" " marked '" "NAME" "'")};; ++(NumIRCS_NAME ); } | ||||||||
| 105 | #define STATS_DECLTRACK_FNRET_ATTR(NAME){ static llvm::Statistic NumIRFunctionReturn_NAME = {"attributor" , "NumIRFunctionReturn_NAME", ("Number of " "function returns" " marked '" "NAME" "'")};; ++(NumIRFunctionReturn_NAME); } \ | ||||||||
| 106 | STATS_DECLTRACK(NAME, FunctionReturn, \{ static llvm::Statistic NumIRFunctionReturn_NAME = {"attributor" , "NumIRFunctionReturn_NAME", ("Number of " "function returns" " marked '" "NAME" "'")};; ++(NumIRFunctionReturn_NAME); } | ||||||||
| 107 | BUILD_STAT_MSG_IR_ATTR(function returns, NAME)){ static llvm::Statistic NumIRFunctionReturn_NAME = {"attributor" , "NumIRFunctionReturn_NAME", ("Number of " "function returns" " marked '" "NAME" "'")};; ++(NumIRFunctionReturn_NAME); } | ||||||||
| 108 | #define STATS_DECLTRACK_CSRET_ATTR(NAME){ static llvm::Statistic NumIRCSReturn_NAME = {"attributor", "NumIRCSReturn_NAME" , ("Number of " "call site returns" " marked '" "NAME" "'")}; ; ++(NumIRCSReturn_NAME); } \ | ||||||||
| 109 | STATS_DECLTRACK(NAME, CSReturn, \{ static llvm::Statistic NumIRCSReturn_NAME = {"attributor", "NumIRCSReturn_NAME" , ("Number of " "call site returns" " marked '" "NAME" "'")}; ; ++(NumIRCSReturn_NAME); } | ||||||||
| 110 | BUILD_STAT_MSG_IR_ATTR(call site returns, NAME)){ static llvm::Statistic NumIRCSReturn_NAME = {"attributor", "NumIRCSReturn_NAME" , ("Number of " "call site returns" " marked '" "NAME" "'")}; ; ++(NumIRCSReturn_NAME); } | ||||||||
| 111 | #define STATS_DECLTRACK_FLOATING_ATTR(NAME){ static llvm::Statistic NumIRFloating_NAME = {"attributor", "NumIRFloating_NAME" , ("Number of floating values known to be '" "NAME" "'")};; ++ (NumIRFloating_NAME); } \ | ||||||||
| 112 | STATS_DECLTRACK(NAME, Floating, \{ static llvm::Statistic NumIRFloating_NAME = {"attributor", "NumIRFloating_NAME" , ("Number of floating values known to be '" #NAME "'")};; ++ (NumIRFloating_NAME); } | ||||||||
| 113 | ("Number of floating values known to be '" #NAME "'")){ static llvm::Statistic NumIRFloating_NAME = {"attributor", "NumIRFloating_NAME" , ("Number of floating values known to be '" #NAME "'")};; ++ (NumIRFloating_NAME); } | ||||||||
| 114 | |||||||||
| 115 | // Specialization of the operator<< for abstract attributes subclasses. This | ||||||||
| 116 | // disambiguates situations where multiple operators are applicable. | ||||||||
| 117 | namespace llvm { | ||||||||
| 118 | #define PIPE_OPERATOR(CLASS) \ | ||||||||
| 119 | raw_ostream &operator<<(raw_ostream &OS, const CLASS &AA) { \ | ||||||||
| 120 | return OS << static_cast<const AbstractAttribute &>(AA); \ | ||||||||
| 121 | } | ||||||||
| 122 | |||||||||
| 123 | PIPE_OPERATOR(AAIsDead) | ||||||||
| 124 | PIPE_OPERATOR(AANoUnwind) | ||||||||
| 125 | PIPE_OPERATOR(AANoSync) | ||||||||
| 126 | PIPE_OPERATOR(AANoRecurse) | ||||||||
| 127 | PIPE_OPERATOR(AAWillReturn) | ||||||||
| 128 | PIPE_OPERATOR(AANoReturn) | ||||||||
| 129 | PIPE_OPERATOR(AAReturnedValues) | ||||||||
| 130 | PIPE_OPERATOR(AANonNull) | ||||||||
| 131 | PIPE_OPERATOR(AANoAlias) | ||||||||
| 132 | PIPE_OPERATOR(AADereferenceable) | ||||||||
| 133 | PIPE_OPERATOR(AAAlign) | ||||||||
| 134 | PIPE_OPERATOR(AANoCapture) | ||||||||
| 135 | PIPE_OPERATOR(AAValueSimplify) | ||||||||
| 136 | PIPE_OPERATOR(AANoFree) | ||||||||
| 137 | PIPE_OPERATOR(AAHeapToStack) | ||||||||
| 138 | PIPE_OPERATOR(AAReachability) | ||||||||
| 139 | PIPE_OPERATOR(AAMemoryBehavior) | ||||||||
| 140 | PIPE_OPERATOR(AAMemoryLocation) | ||||||||
| 141 | PIPE_OPERATOR(AAValueConstantRange) | ||||||||
| 142 | PIPE_OPERATOR(AAPrivatizablePtr) | ||||||||
| 143 | PIPE_OPERATOR(AAUndefinedBehavior) | ||||||||
| 144 | PIPE_OPERATOR(AAPotentialValues) | ||||||||
| 145 | PIPE_OPERATOR(AANoUndef) | ||||||||
| 146 | PIPE_OPERATOR(AACallEdges) | ||||||||
| 147 | PIPE_OPERATOR(AAFunctionReachability) | ||||||||
| 148 | PIPE_OPERATOR(AAPointerInfo) | ||||||||
| 149 | |||||||||
| 150 | #undef PIPE_OPERATOR | ||||||||
| 151 | |||||||||
| 152 | template <> | ||||||||
| 153 | ChangeStatus clampStateAndIndicateChange<DerefState>(DerefState &S, | ||||||||
| 154 | const DerefState &R) { | ||||||||
| 155 | ChangeStatus CS0 = | ||||||||
| 156 | clampStateAndIndicateChange(S.DerefBytesState, R.DerefBytesState); | ||||||||
| 157 | ChangeStatus CS1 = clampStateAndIndicateChange(S.GlobalState, R.GlobalState); | ||||||||
| 158 | return CS0 | CS1; | ||||||||
| 159 | } | ||||||||
| 160 | |||||||||
| 161 | } // namespace llvm | ||||||||
| 162 | |||||||||
| 163 | /// Get pointer operand of memory accessing instruction. If \p I is | ||||||||
| 164 | /// not a memory accessing instruction, return nullptr. If \p AllowVolatile, | ||||||||
| 165 | /// is set to false and the instruction is volatile, return nullptr. | ||||||||
| 166 | static const Value *getPointerOperand(const Instruction *I, | ||||||||
| 167 | bool AllowVolatile) { | ||||||||
| 168 | if (!AllowVolatile && I->isVolatile()) | ||||||||
| 169 | return nullptr; | ||||||||
| 170 | |||||||||
| 171 | if (auto *LI = dyn_cast<LoadInst>(I)) { | ||||||||
| 172 | return LI->getPointerOperand(); | ||||||||
| 173 | } | ||||||||
| 174 | |||||||||
| 175 | if (auto *SI = dyn_cast<StoreInst>(I)) { | ||||||||
| 176 | return SI->getPointerOperand(); | ||||||||
| 177 | } | ||||||||
| 178 | |||||||||
| 179 | if (auto *CXI = dyn_cast<AtomicCmpXchgInst>(I)) { | ||||||||
| 180 | return CXI->getPointerOperand(); | ||||||||
| 181 | } | ||||||||
| 182 | |||||||||
| 183 | if (auto *RMWI = dyn_cast<AtomicRMWInst>(I)) { | ||||||||
| 184 | return RMWI->getPointerOperand(); | ||||||||
| 185 | } | ||||||||
| 186 | |||||||||
| 187 | return nullptr; | ||||||||
| 188 | } | ||||||||
| 189 | |||||||||
| 190 | /// Helper function to create a pointer of type \p ResTy, based on \p Ptr, and | ||||||||
| 191 | /// advanced by \p Offset bytes. To aid later analysis the method tries to build | ||||||||
| 192 | /// getelement pointer instructions that traverse the natural type of \p Ptr if | ||||||||
| 193 | /// possible. If that fails, the remaining offset is adjusted byte-wise, hence | ||||||||
| 194 | /// through a cast to i8*. | ||||||||
| 195 | /// | ||||||||
| 196 | /// TODO: This could probably live somewhere more prominantly if it doesn't | ||||||||
| 197 | /// already exist. | ||||||||
| 198 | static Value *constructPointer(Type *ResTy, Type *PtrElemTy, Value *Ptr, | ||||||||
| 199 | int64_t Offset, IRBuilder<NoFolder> &IRB, | ||||||||
| 200 | const DataLayout &DL) { | ||||||||
| 201 | assert(Offset >= 0 && "Negative offset not supported yet!")((void)0); | ||||||||
| 202 | LLVM_DEBUG(dbgs() << "Construct pointer: " << *Ptr << " + " << Offsetdo { } while (false) | ||||||||
| 203 | << "-bytes as " << *ResTy << "\n")do { } while (false); | ||||||||
| 204 | |||||||||
| 205 | if (Offset) { | ||||||||
| 206 | SmallVector<Value *, 4> Indices; | ||||||||
| 207 | std::string GEPName = Ptr->getName().str() + ".0"; | ||||||||
| 208 | |||||||||
| 209 | // Add 0 index to look through the pointer. | ||||||||
| 210 | assert((uint64_t)Offset < DL.getTypeAllocSize(PtrElemTy) &&((void)0) | ||||||||
| 211 | "Offset out of bounds")((void)0); | ||||||||
| 212 | Indices.push_back(Constant::getNullValue(IRB.getInt32Ty())); | ||||||||
| 213 | |||||||||
| 214 | Type *Ty = PtrElemTy; | ||||||||
| 215 | do { | ||||||||
| 216 | auto *STy = dyn_cast<StructType>(Ty); | ||||||||
| 217 | if (!STy) | ||||||||
| 218 | // Non-aggregate type, we cast and make byte-wise progress now. | ||||||||
| 219 | break; | ||||||||
| 220 | |||||||||
| 221 | const StructLayout *SL = DL.getStructLayout(STy); | ||||||||
| 222 | if (int64_t(SL->getSizeInBytes()) < Offset) | ||||||||
| 223 | break; | ||||||||
| 224 | |||||||||
| 225 | uint64_t Idx = SL->getElementContainingOffset(Offset); | ||||||||
| 226 | assert(Idx < STy->getNumElements() && "Offset calculation error!")((void)0); | ||||||||
| 227 | uint64_t Rem = Offset - SL->getElementOffset(Idx); | ||||||||
| 228 | Ty = STy->getElementType(Idx); | ||||||||
| 229 | |||||||||
| 230 | LLVM_DEBUG(errs() << "Ty: " << *Ty << " Offset: " << Offsetdo { } while (false) | ||||||||
| 231 | << " Idx: " << Idx << " Rem: " << Rem << "\n")do { } while (false); | ||||||||
| 232 | |||||||||
| 233 | GEPName += "." + std::to_string(Idx); | ||||||||
| 234 | Indices.push_back(ConstantInt::get(IRB.getInt32Ty(), Idx)); | ||||||||
| 235 | Offset = Rem; | ||||||||
| 236 | } while (Offset); | ||||||||
| 237 | |||||||||
| 238 | // Create a GEP for the indices collected above. | ||||||||
| 239 | Ptr = IRB.CreateGEP(PtrElemTy, Ptr, Indices, GEPName); | ||||||||
| 240 | |||||||||
| 241 | // If an offset is left we use byte-wise adjustment. | ||||||||
| 242 | if (Offset) { | ||||||||
| 243 | Ptr = IRB.CreateBitCast(Ptr, IRB.getInt8PtrTy()); | ||||||||
| 244 | Ptr = IRB.CreateGEP(IRB.getInt8Ty(), Ptr, IRB.getInt32(Offset), | ||||||||
| 245 | GEPName + ".b" + Twine(Offset)); | ||||||||
| 246 | } | ||||||||
| 247 | } | ||||||||
| 248 | |||||||||
| 249 | // Ensure the result has the requested type. | ||||||||
| 250 | Ptr = IRB.CreateBitOrPointerCast(Ptr, ResTy, Ptr->getName() + ".cast"); | ||||||||
| 251 | |||||||||
| 252 | LLVM_DEBUG(dbgs() << "Constructed pointer: " << *Ptr << "\n")do { } while (false); | ||||||||
| 253 | return Ptr; | ||||||||
| 254 | } | ||||||||
| 255 | |||||||||
| 256 | /// Recursively visit all values that might become \p IRP at some point. This | ||||||||
| 257 | /// will be done by looking through cast instructions, selects, phis, and calls | ||||||||
| 258 | /// with the "returned" attribute. Once we cannot look through the value any | ||||||||
| 259 | /// further, the callback \p VisitValueCB is invoked and passed the current | ||||||||
| 260 | /// value, the \p State, and a flag to indicate if we stripped anything. | ||||||||
| 261 | /// Stripped means that we unpacked the value associated with \p IRP at least | ||||||||
| 262 | /// once. Note that the value used for the callback may still be the value | ||||||||
| 263 | /// associated with \p IRP (due to PHIs). To limit how much effort is invested, | ||||||||
| 264 | /// we will never visit more values than specified by \p MaxValues. | ||||||||
| 265 | template <typename StateTy> | ||||||||
| 266 | static bool genericValueTraversal( | ||||||||
| 267 | Attributor &A, IRPosition IRP, const AbstractAttribute &QueryingAA, | ||||||||
| 268 | StateTy &State, | ||||||||
| 269 | function_ref<bool(Value &, const Instruction *, StateTy &, bool)> | ||||||||
| 270 | VisitValueCB, | ||||||||
| 271 | const Instruction *CtxI, bool UseValueSimplify = true, int MaxValues = 16, | ||||||||
| 272 | function_ref<Value *(Value *)> StripCB = nullptr) { | ||||||||
| 273 | |||||||||
| 274 | const AAIsDead *LivenessAA = nullptr; | ||||||||
| 275 | if (IRP.getAnchorScope()) | ||||||||
| 276 | LivenessAA = &A.getAAFor<AAIsDead>( | ||||||||
| 277 | QueryingAA, | ||||||||
| 278 | IRPosition::function(*IRP.getAnchorScope(), IRP.getCallBaseContext()), | ||||||||
| 279 | DepClassTy::NONE); | ||||||||
| 280 | bool AnyDead = false; | ||||||||
| 281 | |||||||||
| 282 | Value *InitialV = &IRP.getAssociatedValue(); | ||||||||
| 283 | using Item = std::pair<Value *, const Instruction *>; | ||||||||
| 284 | SmallSet<Item, 16> Visited; | ||||||||
| 285 | SmallVector<Item, 16> Worklist; | ||||||||
| 286 | Worklist.push_back({InitialV, CtxI}); | ||||||||
| 287 | |||||||||
| 288 | int Iteration = 0; | ||||||||
| 289 | do { | ||||||||
| 290 | Item I = Worklist.pop_back_val(); | ||||||||
| 291 | Value *V = I.first; | ||||||||
| 292 | CtxI = I.second; | ||||||||
| 293 | if (StripCB) | ||||||||
| 294 | V = StripCB(V); | ||||||||
| 295 | |||||||||
| 296 | // Check if we should process the current value. To prevent endless | ||||||||
| 297 | // recursion keep a record of the values we followed! | ||||||||
| 298 | if (!Visited.insert(I).second) | ||||||||
| 299 | continue; | ||||||||
| 300 | |||||||||
| 301 | // Make sure we limit the compile time for complex expressions. | ||||||||
| 302 | if (Iteration++ >= MaxValues) | ||||||||
| 303 | return false; | ||||||||
| 304 | |||||||||
| 305 | // Explicitly look through calls with a "returned" attribute if we do | ||||||||
| 306 | // not have a pointer as stripPointerCasts only works on them. | ||||||||
| 307 | Value *NewV = nullptr; | ||||||||
| 308 | if (V->getType()->isPointerTy()) { | ||||||||
| 309 | NewV = V->stripPointerCasts(); | ||||||||
| 310 | } else { | ||||||||
| 311 | auto *CB = dyn_cast<CallBase>(V); | ||||||||
| 312 | if (CB && CB->getCalledFunction()) { | ||||||||
| 313 | for (Argument &Arg : CB->getCalledFunction()->args()) | ||||||||
| 314 | if (Arg.hasReturnedAttr()) { | ||||||||
| 315 | NewV = CB->getArgOperand(Arg.getArgNo()); | ||||||||
| 316 | break; | ||||||||
| 317 | } | ||||||||
| 318 | } | ||||||||
| 319 | } | ||||||||
| 320 | if (NewV && NewV != V) { | ||||||||
| 321 | Worklist.push_back({NewV, CtxI}); | ||||||||
| 322 | continue; | ||||||||
| 323 | } | ||||||||
| 324 | |||||||||
| 325 | // Look through select instructions, visit assumed potential values. | ||||||||
| 326 | if (auto *SI = dyn_cast<SelectInst>(V)) { | ||||||||
| 327 | bool UsedAssumedInformation = false; | ||||||||
| 328 | Optional<Constant *> C = A.getAssumedConstant( | ||||||||
| 329 | *SI->getCondition(), QueryingAA, UsedAssumedInformation); | ||||||||
| 330 | bool NoValueYet = !C.hasValue(); | ||||||||
| 331 | if (NoValueYet || isa_and_nonnull<UndefValue>(*C)) | ||||||||
| 332 | continue; | ||||||||
| 333 | if (auto *CI = dyn_cast_or_null<ConstantInt>(*C)) { | ||||||||
| 334 | if (CI->isZero()) | ||||||||
| 335 | Worklist.push_back({SI->getFalseValue(), CtxI}); | ||||||||
| 336 | else | ||||||||
| 337 | Worklist.push_back({SI->getTrueValue(), CtxI}); | ||||||||
| 338 | continue; | ||||||||
| 339 | } | ||||||||
| 340 | // We could not simplify the condition, assume both values.( | ||||||||
| 341 | Worklist.push_back({SI->getTrueValue(), CtxI}); | ||||||||
| 342 | Worklist.push_back({SI->getFalseValue(), CtxI}); | ||||||||
| 343 | continue; | ||||||||
| 344 | } | ||||||||
| 345 | |||||||||
| 346 | // Look through phi nodes, visit all live operands. | ||||||||
| 347 | if (auto *PHI = dyn_cast<PHINode>(V)) { | ||||||||
| 348 | assert(LivenessAA &&((void)0) | ||||||||
| 349 | "Expected liveness in the presence of instructions!")((void)0); | ||||||||
| 350 | for (unsigned u = 0, e = PHI->getNumIncomingValues(); u < e; u++) { | ||||||||
| 351 | BasicBlock *IncomingBB = PHI->getIncomingBlock(u); | ||||||||
| 352 | bool UsedAssumedInformation = false; | ||||||||
| 353 | if (A.isAssumedDead(*IncomingBB->getTerminator(), &QueryingAA, | ||||||||
| 354 | LivenessAA, UsedAssumedInformation, | ||||||||
| 355 | /* CheckBBLivenessOnly */ true)) { | ||||||||
| 356 | AnyDead = true; | ||||||||
| 357 | continue; | ||||||||
| 358 | } | ||||||||
| 359 | Worklist.push_back( | ||||||||
| 360 | {PHI->getIncomingValue(u), IncomingBB->getTerminator()}); | ||||||||
| 361 | } | ||||||||
| 362 | continue; | ||||||||
| 363 | } | ||||||||
| 364 | |||||||||
| 365 | if (UseValueSimplify && !isa<Constant>(V)) { | ||||||||
| 366 | bool UsedAssumedInformation = false; | ||||||||
| 367 | Optional<Value *> SimpleV = | ||||||||
| 368 | A.getAssumedSimplified(*V, QueryingAA, UsedAssumedInformation); | ||||||||
| 369 | if (!SimpleV.hasValue()) | ||||||||
| 370 | continue; | ||||||||
| 371 | if (!SimpleV.getValue()) | ||||||||
| 372 | return false; | ||||||||
| 373 | Value *NewV = SimpleV.getValue(); | ||||||||
| 374 | if (NewV != V) { | ||||||||
| 375 | Worklist.push_back({NewV, CtxI}); | ||||||||
| 376 | continue; | ||||||||
| 377 | } | ||||||||
| 378 | } | ||||||||
| 379 | |||||||||
| 380 | // Once a leaf is reached we inform the user through the callback. | ||||||||
| 381 | if (!VisitValueCB(*V, CtxI, State, Iteration > 1)) | ||||||||
| 382 | return false; | ||||||||
| 383 | } while (!Worklist.empty()); | ||||||||
| 384 | |||||||||
| 385 | // If we actually used liveness information so we have to record a dependence. | ||||||||
| 386 | if (AnyDead) | ||||||||
| 387 | A.recordDependence(*LivenessAA, QueryingAA, DepClassTy::OPTIONAL); | ||||||||
| 388 | |||||||||
| 389 | // All values have been visited. | ||||||||
| 390 | return true; | ||||||||
| 391 | } | ||||||||
| 392 | |||||||||
| 393 | bool AA::getAssumedUnderlyingObjects(Attributor &A, const Value &Ptr, | ||||||||
| 394 | SmallVectorImpl<Value *> &Objects, | ||||||||
| 395 | const AbstractAttribute &QueryingAA, | ||||||||
| 396 | const Instruction *CtxI) { | ||||||||
| 397 | auto StripCB = [&](Value *V) { return getUnderlyingObject(V); }; | ||||||||
| 398 | SmallPtrSet<Value *, 8> SeenObjects; | ||||||||
| 399 | auto VisitValueCB = [&SeenObjects](Value &Val, const Instruction *, | ||||||||
| 400 | SmallVectorImpl<Value *> &Objects, | ||||||||
| 401 | bool) -> bool { | ||||||||
| 402 | if (SeenObjects.insert(&Val).second) | ||||||||
| 403 | Objects.push_back(&Val); | ||||||||
| 404 | return true; | ||||||||
| 405 | }; | ||||||||
| 406 | if (!genericValueTraversal<decltype(Objects)>( | ||||||||
| 407 | A, IRPosition::value(Ptr), QueryingAA, Objects, VisitValueCB, CtxI, | ||||||||
| 408 | true, 32, StripCB)) | ||||||||
| 409 | return false; | ||||||||
| 410 | return true; | ||||||||
| 411 | } | ||||||||
| 412 | |||||||||
| 413 | const Value *stripAndAccumulateMinimalOffsets( | ||||||||
| 414 | Attributor &A, const AbstractAttribute &QueryingAA, const Value *Val, | ||||||||
| 415 | const DataLayout &DL, APInt &Offset, bool AllowNonInbounds, | ||||||||
| 416 | bool UseAssumed = false) { | ||||||||
| 417 | |||||||||
| 418 | auto AttributorAnalysis = [&](Value &V, APInt &ROffset) -> bool { | ||||||||
| 419 | const IRPosition &Pos = IRPosition::value(V); | ||||||||
| 420 | // Only track dependence if we are going to use the assumed info. | ||||||||
| 421 | const AAValueConstantRange &ValueConstantRangeAA = | ||||||||
| 422 | A.getAAFor<AAValueConstantRange>(QueryingAA, Pos, | ||||||||
| 423 | UseAssumed ? DepClassTy::OPTIONAL | ||||||||
| 424 | : DepClassTy::NONE); | ||||||||
| 425 | ConstantRange Range = UseAssumed ? ValueConstantRangeAA.getAssumed() | ||||||||
| 426 | : ValueConstantRangeAA.getKnown(); | ||||||||
| 427 | // We can only use the lower part of the range because the upper part can | ||||||||
| 428 | // be higher than what the value can really be. | ||||||||
| 429 | ROffset = Range.getSignedMin(); | ||||||||
| 430 | return true; | ||||||||
| 431 | }; | ||||||||
| 432 | |||||||||
| 433 | return Val->stripAndAccumulateConstantOffsets(DL, Offset, AllowNonInbounds, | ||||||||
| 434 | AttributorAnalysis); | ||||||||
| 435 | } | ||||||||
| 436 | |||||||||
| 437 | static const Value *getMinimalBaseOfAccsesPointerOperand( | ||||||||
| 438 | Attributor &A, const AbstractAttribute &QueryingAA, const Instruction *I, | ||||||||
| 439 | int64_t &BytesOffset, const DataLayout &DL, bool AllowNonInbounds = false) { | ||||||||
| 440 | const Value *Ptr = getPointerOperand(I, /* AllowVolatile */ false); | ||||||||
| 441 | if (!Ptr) | ||||||||
| 442 | return nullptr; | ||||||||
| 443 | APInt OffsetAPInt(DL.getIndexTypeSizeInBits(Ptr->getType()), 0); | ||||||||
| 444 | const Value *Base = stripAndAccumulateMinimalOffsets( | ||||||||
| 445 | A, QueryingAA, Ptr, DL, OffsetAPInt, AllowNonInbounds); | ||||||||
| 446 | |||||||||
| 447 | BytesOffset = OffsetAPInt.getSExtValue(); | ||||||||
| 448 | return Base; | ||||||||
| 449 | } | ||||||||
| 450 | |||||||||
| 451 | static const Value * | ||||||||
| 452 | getBasePointerOfAccessPointerOperand(const Instruction *I, int64_t &BytesOffset, | ||||||||
| 453 | const DataLayout &DL, | ||||||||
| 454 | bool AllowNonInbounds = false) { | ||||||||
| 455 | const Value *Ptr = getPointerOperand(I, /* AllowVolatile */ false); | ||||||||
| 456 | if (!Ptr) | ||||||||
| 457 | return nullptr; | ||||||||
| 458 | |||||||||
| 459 | return GetPointerBaseWithConstantOffset(Ptr, BytesOffset, DL, | ||||||||
| 460 | AllowNonInbounds); | ||||||||
| 461 | } | ||||||||
| 462 | |||||||||
| 463 | /// Clamp the information known for all returned values of a function | ||||||||
| 464 | /// (identified by \p QueryingAA) into \p S. | ||||||||
| 465 | template <typename AAType, typename StateType = typename AAType::StateType> | ||||||||
| 466 | static void clampReturnedValueStates( | ||||||||
| 467 | Attributor &A, const AAType &QueryingAA, StateType &S, | ||||||||
| 468 | const IRPosition::CallBaseContext *CBContext = nullptr) { | ||||||||
| 469 | LLVM_DEBUG(dbgs() << "[Attributor] Clamp return value states for "do { } while (false) | ||||||||
| 470 | << QueryingAA << " into " << S << "\n")do { } while (false); | ||||||||
| 471 | |||||||||
| 472 | assert((QueryingAA.getIRPosition().getPositionKind() ==((void)0) | ||||||||
| 473 | IRPosition::IRP_RETURNED ||((void)0) | ||||||||
| 474 | QueryingAA.getIRPosition().getPositionKind() ==((void)0) | ||||||||
| 475 | IRPosition::IRP_CALL_SITE_RETURNED) &&((void)0) | ||||||||
| 476 | "Can only clamp returned value states for a function returned or call "((void)0) | ||||||||
| 477 | "site returned position!")((void)0); | ||||||||
| 478 | |||||||||
| 479 | // Use an optional state as there might not be any return values and we want | ||||||||
| 480 | // to join (IntegerState::operator&) the state of all there are. | ||||||||
| 481 | Optional<StateType> T; | ||||||||
| 482 | |||||||||
| 483 | // Callback for each possibly returned value. | ||||||||
| 484 | auto CheckReturnValue = [&](Value &RV) -> bool { | ||||||||
| 485 | const IRPosition &RVPos = IRPosition::value(RV, CBContext); | ||||||||
| 486 | const AAType &AA = | ||||||||
| 487 | A.getAAFor<AAType>(QueryingAA, RVPos, DepClassTy::REQUIRED); | ||||||||
| 488 | LLVM_DEBUG(dbgs() << "[Attributor] RV: " << RV << " AA: " << AA.getAsStr()do { } while (false) | ||||||||
| 489 | << " @ " << RVPos << "\n")do { } while (false); | ||||||||
| 490 | const StateType &AAS = AA.getState(); | ||||||||
| 491 | if (T.hasValue()) | ||||||||
| 492 | *T &= AAS; | ||||||||
| 493 | else | ||||||||
| 494 | T = AAS; | ||||||||
| 495 | LLVM_DEBUG(dbgs() << "[Attributor] AA State: " << AAS << " RV State: " << Tdo { } while (false) | ||||||||
| 496 | << "\n")do { } while (false); | ||||||||
| 497 | return T->isValidState(); | ||||||||
| 498 | }; | ||||||||
| 499 | |||||||||
| 500 | if (!A.checkForAllReturnedValues(CheckReturnValue, QueryingAA)) | ||||||||
| 501 | S.indicatePessimisticFixpoint(); | ||||||||
| 502 | else if (T.hasValue()) | ||||||||
| 503 | S ^= *T; | ||||||||
| 504 | } | ||||||||
| 505 | |||||||||
| 506 | /// Helper class for generic deduction: return value -> returned position. | ||||||||
| 507 | template <typename AAType, typename BaseType, | ||||||||
| 508 | typename StateType = typename BaseType::StateType, | ||||||||
| 509 | bool PropagateCallBaseContext = false> | ||||||||
| 510 | struct AAReturnedFromReturnedValues : public BaseType { | ||||||||
| 511 | AAReturnedFromReturnedValues(const IRPosition &IRP, Attributor &A) | ||||||||
| 512 | : BaseType(IRP, A) {} | ||||||||
| 513 | |||||||||
| 514 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 515 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 516 | StateType S(StateType::getBestState(this->getState())); | ||||||||
| 517 | clampReturnedValueStates<AAType, StateType>( | ||||||||
| 518 | A, *this, S, | ||||||||
| 519 | PropagateCallBaseContext ? this->getCallBaseContext() : nullptr); | ||||||||
| 520 | // TODO: If we know we visited all returned values, thus no are assumed | ||||||||
| 521 | // dead, we can take the known information from the state T. | ||||||||
| 522 | return clampStateAndIndicateChange<StateType>(this->getState(), S); | ||||||||
| 523 | } | ||||||||
| 524 | }; | ||||||||
| 525 | |||||||||
| 526 | /// Clamp the information known at all call sites for a given argument | ||||||||
| 527 | /// (identified by \p QueryingAA) into \p S. | ||||||||
| 528 | template <typename AAType, typename StateType = typename AAType::StateType> | ||||||||
| 529 | static void clampCallSiteArgumentStates(Attributor &A, const AAType &QueryingAA, | ||||||||
| 530 | StateType &S) { | ||||||||
| 531 | LLVM_DEBUG(dbgs() << "[Attributor] Clamp call site argument states for "do { } while (false) | ||||||||
| 532 | << QueryingAA << " into " << S << "\n")do { } while (false); | ||||||||
| 533 | |||||||||
| 534 | assert(QueryingAA.getIRPosition().getPositionKind() ==((void)0) | ||||||||
| 535 | IRPosition::IRP_ARGUMENT &&((void)0) | ||||||||
| 536 | "Can only clamp call site argument states for an argument position!")((void)0); | ||||||||
| 537 | |||||||||
| 538 | // Use an optional state as there might not be any return values and we want | ||||||||
| 539 | // to join (IntegerState::operator&) the state of all there are. | ||||||||
| 540 | Optional<StateType> T; | ||||||||
| 541 | |||||||||
| 542 | // The argument number which is also the call site argument number. | ||||||||
| 543 | unsigned ArgNo = QueryingAA.getIRPosition().getCallSiteArgNo(); | ||||||||
| 544 | |||||||||
| 545 | auto CallSiteCheck = [&](AbstractCallSite ACS) { | ||||||||
| 546 | const IRPosition &ACSArgPos = IRPosition::callsite_argument(ACS, ArgNo); | ||||||||
| 547 | // Check if a coresponding argument was found or if it is on not associated | ||||||||
| 548 | // (which can happen for callback calls). | ||||||||
| 549 | if (ACSArgPos.getPositionKind() == IRPosition::IRP_INVALID) | ||||||||
| 550 | return false; | ||||||||
| 551 | |||||||||
| 552 | const AAType &AA = | ||||||||
| 553 | A.getAAFor<AAType>(QueryingAA, ACSArgPos, DepClassTy::REQUIRED); | ||||||||
| 554 | LLVM_DEBUG(dbgs() << "[Attributor] ACS: " << *ACS.getInstruction()do { } while (false) | ||||||||
| 555 | << " AA: " << AA.getAsStr() << " @" << ACSArgPos << "\n")do { } while (false); | ||||||||
| 556 | const StateType &AAS = AA.getState(); | ||||||||
| 557 | if (T.hasValue()) | ||||||||
| 558 | *T &= AAS; | ||||||||
| 559 | else | ||||||||
| 560 | T = AAS; | ||||||||
| 561 | LLVM_DEBUG(dbgs() << "[Attributor] AA State: " << AAS << " CSA State: " << Tdo { } while (false) | ||||||||
| 562 | << "\n")do { } while (false); | ||||||||
| 563 | return T->isValidState(); | ||||||||
| 564 | }; | ||||||||
| 565 | |||||||||
| 566 | bool AllCallSitesKnown; | ||||||||
| 567 | if (!A.checkForAllCallSites(CallSiteCheck, QueryingAA, true, | ||||||||
| 568 | AllCallSitesKnown)) | ||||||||
| 569 | S.indicatePessimisticFixpoint(); | ||||||||
| 570 | else if (T.hasValue()) | ||||||||
| 571 | S ^= *T; | ||||||||
| 572 | } | ||||||||
| 573 | |||||||||
| 574 | /// This function is the bridge between argument position and the call base | ||||||||
| 575 | /// context. | ||||||||
| 576 | template <typename AAType, typename BaseType, | ||||||||
| 577 | typename StateType = typename AAType::StateType> | ||||||||
| 578 | bool getArgumentStateFromCallBaseContext(Attributor &A, | ||||||||
| 579 | BaseType &QueryingAttribute, | ||||||||
| 580 | IRPosition &Pos, StateType &State) { | ||||||||
| 581 | assert((Pos.getPositionKind() == IRPosition::IRP_ARGUMENT) &&((void)0) | ||||||||
| 582 | "Expected an 'argument' position !")((void)0); | ||||||||
| 583 | const CallBase *CBContext = Pos.getCallBaseContext(); | ||||||||
| 584 | if (!CBContext) | ||||||||
| 585 | return false; | ||||||||
| 586 | |||||||||
| 587 | int ArgNo = Pos.getCallSiteArgNo(); | ||||||||
| 588 | assert(ArgNo >= 0 && "Invalid Arg No!")((void)0); | ||||||||
| 589 | |||||||||
| 590 | const auto &AA = A.getAAFor<AAType>( | ||||||||
| 591 | QueryingAttribute, IRPosition::callsite_argument(*CBContext, ArgNo), | ||||||||
| 592 | DepClassTy::REQUIRED); | ||||||||
| 593 | const StateType &CBArgumentState = | ||||||||
| 594 | static_cast<const StateType &>(AA.getState()); | ||||||||
| 595 | |||||||||
| 596 | LLVM_DEBUG(dbgs() << "[Attributor] Briding Call site context to argument"do { } while (false) | ||||||||
| 597 | << "Position:" << Pos << "CB Arg state:" << CBArgumentStatedo { } while (false) | ||||||||
| 598 | << "\n")do { } while (false); | ||||||||
| 599 | |||||||||
| 600 | // NOTE: If we want to do call site grouping it should happen here. | ||||||||
| 601 | State ^= CBArgumentState; | ||||||||
| 602 | return true; | ||||||||
| 603 | } | ||||||||
| 604 | |||||||||
| 605 | /// Helper class for generic deduction: call site argument -> argument position. | ||||||||
| 606 | template <typename AAType, typename BaseType, | ||||||||
| 607 | typename StateType = typename AAType::StateType, | ||||||||
| 608 | bool BridgeCallBaseContext = false> | ||||||||
| 609 | struct AAArgumentFromCallSiteArguments : public BaseType { | ||||||||
| 610 | AAArgumentFromCallSiteArguments(const IRPosition &IRP, Attributor &A) | ||||||||
| 611 | : BaseType(IRP, A) {} | ||||||||
| 612 | |||||||||
| 613 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 614 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 615 | StateType S = StateType::getBestState(this->getState()); | ||||||||
| 616 | |||||||||
| 617 | if (BridgeCallBaseContext) { | ||||||||
| 618 | bool Success = | ||||||||
| 619 | getArgumentStateFromCallBaseContext<AAType, BaseType, StateType>( | ||||||||
| 620 | A, *this, this->getIRPosition(), S); | ||||||||
| 621 | if (Success) | ||||||||
| 622 | return clampStateAndIndicateChange<StateType>(this->getState(), S); | ||||||||
| 623 | } | ||||||||
| 624 | clampCallSiteArgumentStates<AAType, StateType>(A, *this, S); | ||||||||
| 625 | |||||||||
| 626 | // TODO: If we know we visited all incoming values, thus no are assumed | ||||||||
| 627 | // dead, we can take the known information from the state T. | ||||||||
| 628 | return clampStateAndIndicateChange<StateType>(this->getState(), S); | ||||||||
| 629 | } | ||||||||
| 630 | }; | ||||||||
| 631 | |||||||||
| 632 | /// Helper class for generic replication: function returned -> cs returned. | ||||||||
| 633 | template <typename AAType, typename BaseType, | ||||||||
| 634 | typename StateType = typename BaseType::StateType, | ||||||||
| 635 | bool IntroduceCallBaseContext = false> | ||||||||
| 636 | struct AACallSiteReturnedFromReturned : public BaseType { | ||||||||
| 637 | AACallSiteReturnedFromReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 638 | : BaseType(IRP, A) {} | ||||||||
| 639 | |||||||||
| 640 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 641 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 642 | assert(this->getIRPosition().getPositionKind() ==((void)0) | ||||||||
| 643 | IRPosition::IRP_CALL_SITE_RETURNED &&((void)0) | ||||||||
| 644 | "Can only wrap function returned positions for call site returned "((void)0) | ||||||||
| 645 | "positions!")((void)0); | ||||||||
| 646 | auto &S = this->getState(); | ||||||||
| 647 | |||||||||
| 648 | const Function *AssociatedFunction = | ||||||||
| 649 | this->getIRPosition().getAssociatedFunction(); | ||||||||
| 650 | if (!AssociatedFunction) | ||||||||
| 651 | return S.indicatePessimisticFixpoint(); | ||||||||
| 652 | |||||||||
| 653 | CallBase &CBContext = static_cast<CallBase &>(this->getAnchorValue()); | ||||||||
| 654 | if (IntroduceCallBaseContext) | ||||||||
| 655 | LLVM_DEBUG(dbgs() << "[Attributor] Introducing call base context:"do { } while (false) | ||||||||
| 656 | << CBContext << "\n")do { } while (false); | ||||||||
| 657 | |||||||||
| 658 | IRPosition FnPos = IRPosition::returned( | ||||||||
| 659 | *AssociatedFunction, IntroduceCallBaseContext ? &CBContext : nullptr); | ||||||||
| 660 | const AAType &AA = A.getAAFor<AAType>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 661 | return clampStateAndIndicateChange(S, AA.getState()); | ||||||||
| 662 | } | ||||||||
| 663 | }; | ||||||||
| 664 | |||||||||
| 665 | /// Helper function to accumulate uses. | ||||||||
| 666 | template <class AAType, typename StateType = typename AAType::StateType> | ||||||||
| 667 | static void followUsesInContext(AAType &AA, Attributor &A, | ||||||||
| 668 | MustBeExecutedContextExplorer &Explorer, | ||||||||
| 669 | const Instruction *CtxI, | ||||||||
| 670 | SetVector<const Use *> &Uses, | ||||||||
| 671 | StateType &State) { | ||||||||
| 672 | auto EIt = Explorer.begin(CtxI), EEnd = Explorer.end(CtxI); | ||||||||
| 673 | for (unsigned u = 0; u < Uses.size(); ++u) { | ||||||||
| 674 | const Use *U = Uses[u]; | ||||||||
| 675 | if (const Instruction *UserI = dyn_cast<Instruction>(U->getUser())) { | ||||||||
| 676 | bool Found = Explorer.findInContextOf(UserI, EIt, EEnd); | ||||||||
| 677 | if (Found && AA.followUseInMBEC(A, U, UserI, State)) | ||||||||
| 678 | for (const Use &Us : UserI->uses()) | ||||||||
| 679 | Uses.insert(&Us); | ||||||||
| 680 | } | ||||||||
| 681 | } | ||||||||
| 682 | } | ||||||||
| 683 | |||||||||
| 684 | /// Use the must-be-executed-context around \p I to add information into \p S. | ||||||||
| 685 | /// The AAType class is required to have `followUseInMBEC` method with the | ||||||||
| 686 | /// following signature and behaviour: | ||||||||
| 687 | /// | ||||||||
| 688 | /// bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I) | ||||||||
| 689 | /// U - Underlying use. | ||||||||
| 690 | /// I - The user of the \p U. | ||||||||
| 691 | /// Returns true if the value should be tracked transitively. | ||||||||
| 692 | /// | ||||||||
| 693 | template <class AAType, typename StateType = typename AAType::StateType> | ||||||||
| 694 | static void followUsesInMBEC(AAType &AA, Attributor &A, StateType &S, | ||||||||
| 695 | Instruction &CtxI) { | ||||||||
| 696 | |||||||||
| 697 | // Container for (transitive) uses of the associated value. | ||||||||
| 698 | SetVector<const Use *> Uses; | ||||||||
| 699 | for (const Use &U : AA.getIRPosition().getAssociatedValue().uses()) | ||||||||
| 700 | Uses.insert(&U); | ||||||||
| 701 | |||||||||
| 702 | MustBeExecutedContextExplorer &Explorer = | ||||||||
| 703 | A.getInfoCache().getMustBeExecutedContextExplorer(); | ||||||||
| 704 | |||||||||
| 705 | followUsesInContext<AAType>(AA, A, Explorer, &CtxI, Uses, S); | ||||||||
| 706 | |||||||||
| 707 | if (S.isAtFixpoint()) | ||||||||
| 708 | return; | ||||||||
| 709 | |||||||||
| 710 | SmallVector<const BranchInst *, 4> BrInsts; | ||||||||
| 711 | auto Pred = [&](const Instruction *I) { | ||||||||
| 712 | if (const BranchInst *Br = dyn_cast<BranchInst>(I)) | ||||||||
| 713 | if (Br->isConditional()) | ||||||||
| 714 | BrInsts.push_back(Br); | ||||||||
| 715 | return true; | ||||||||
| 716 | }; | ||||||||
| 717 | |||||||||
| 718 | // Here, accumulate conditional branch instructions in the context. We | ||||||||
| 719 | // explore the child paths and collect the known states. The disjunction of | ||||||||
| 720 | // those states can be merged to its own state. Let ParentState_i be a state | ||||||||
| 721 | // to indicate the known information for an i-th branch instruction in the | ||||||||
| 722 | // context. ChildStates are created for its successors respectively. | ||||||||
| 723 | // | ||||||||
| 724 | // ParentS_1 = ChildS_{1, 1} /\ ChildS_{1, 2} /\ ... /\ ChildS_{1, n_1} | ||||||||
| 725 | // ParentS_2 = ChildS_{2, 1} /\ ChildS_{2, 2} /\ ... /\ ChildS_{2, n_2} | ||||||||
| 726 | // ... | ||||||||
| 727 | // ParentS_m = ChildS_{m, 1} /\ ChildS_{m, 2} /\ ... /\ ChildS_{m, n_m} | ||||||||
| 728 | // | ||||||||
| 729 | // Known State |= ParentS_1 \/ ParentS_2 \/... \/ ParentS_m | ||||||||
| 730 | // | ||||||||
| 731 | // FIXME: Currently, recursive branches are not handled. For example, we | ||||||||
| 732 | // can't deduce that ptr must be dereferenced in below function. | ||||||||
| 733 | // | ||||||||
| 734 | // void f(int a, int c, int *ptr) { | ||||||||
| 735 | // if(a) | ||||||||
| 736 | // if (b) { | ||||||||
| 737 | // *ptr = 0; | ||||||||
| 738 | // } else { | ||||||||
| 739 | // *ptr = 1; | ||||||||
| 740 | // } | ||||||||
| 741 | // else { | ||||||||
| 742 | // if (b) { | ||||||||
| 743 | // *ptr = 0; | ||||||||
| 744 | // } else { | ||||||||
| 745 | // *ptr = 1; | ||||||||
| 746 | // } | ||||||||
| 747 | // } | ||||||||
| 748 | // } | ||||||||
| 749 | |||||||||
| 750 | Explorer.checkForAllContext(&CtxI, Pred); | ||||||||
| 751 | for (const BranchInst *Br : BrInsts) { | ||||||||
| 752 | StateType ParentState; | ||||||||
| 753 | |||||||||
| 754 | // The known state of the parent state is a conjunction of children's | ||||||||
| 755 | // known states so it is initialized with a best state. | ||||||||
| 756 | ParentState.indicateOptimisticFixpoint(); | ||||||||
| 757 | |||||||||
| 758 | for (const BasicBlock *BB : Br->successors()) { | ||||||||
| 759 | StateType ChildState; | ||||||||
| 760 | |||||||||
| 761 | size_t BeforeSize = Uses.size(); | ||||||||
| 762 | followUsesInContext(AA, A, Explorer, &BB->front(), Uses, ChildState); | ||||||||
| 763 | |||||||||
| 764 | // Erase uses which only appear in the child. | ||||||||
| 765 | for (auto It = Uses.begin() + BeforeSize; It != Uses.end();) | ||||||||
| 766 | It = Uses.erase(It); | ||||||||
| 767 | |||||||||
| 768 | ParentState &= ChildState; | ||||||||
| 769 | } | ||||||||
| 770 | |||||||||
| 771 | // Use only known state. | ||||||||
| 772 | S += ParentState; | ||||||||
| 773 | } | ||||||||
| 774 | } | ||||||||
| 775 | |||||||||
| 776 | /// ------------------------ PointerInfo --------------------------------------- | ||||||||
| 777 | |||||||||
| 778 | namespace llvm { | ||||||||
| 779 | namespace AA { | ||||||||
| 780 | namespace PointerInfo { | ||||||||
| 781 | |||||||||
| 782 | /// An access kind description as used by AAPointerInfo. | ||||||||
| 783 | struct OffsetAndSize; | ||||||||
| 784 | |||||||||
| 785 | struct State; | ||||||||
| 786 | |||||||||
| 787 | } // namespace PointerInfo | ||||||||
| 788 | } // namespace AA | ||||||||
| 789 | |||||||||
| 790 | /// Helper for AA::PointerInfo::Acccess DenseMap/Set usage. | ||||||||
| 791 | template <> | ||||||||
| 792 | struct DenseMapInfo<AAPointerInfo::Access> : DenseMapInfo<Instruction *> { | ||||||||
| 793 | using Access = AAPointerInfo::Access; | ||||||||
| 794 | static inline Access getEmptyKey(); | ||||||||
| 795 | static inline Access getTombstoneKey(); | ||||||||
| 796 | static unsigned getHashValue(const Access &A); | ||||||||
| 797 | static bool isEqual(const Access &LHS, const Access &RHS); | ||||||||
| 798 | }; | ||||||||
| 799 | |||||||||
| 800 | /// Helper that allows OffsetAndSize as a key in a DenseMap. | ||||||||
| 801 | template <> | ||||||||
| 802 | struct DenseMapInfo<AA::PointerInfo ::OffsetAndSize> | ||||||||
| 803 | : DenseMapInfo<std::pair<int64_t, int64_t>> {}; | ||||||||
| 804 | |||||||||
| 805 | /// Helper for AA::PointerInfo::Acccess DenseMap/Set usage ignoring everythign | ||||||||
| 806 | /// but the instruction | ||||||||
| 807 | struct AccessAsInstructionInfo : DenseMapInfo<Instruction *> { | ||||||||
| 808 | using Base = DenseMapInfo<Instruction *>; | ||||||||
| 809 | using Access = AAPointerInfo::Access; | ||||||||
| 810 | static inline Access getEmptyKey(); | ||||||||
| 811 | static inline Access getTombstoneKey(); | ||||||||
| 812 | static unsigned getHashValue(const Access &A); | ||||||||
| 813 | static bool isEqual(const Access &LHS, const Access &RHS); | ||||||||
| 814 | }; | ||||||||
| 815 | |||||||||
| 816 | } // namespace llvm | ||||||||
| 817 | |||||||||
| 818 | /// Helper to represent an access offset and size, with logic to deal with | ||||||||
| 819 | /// uncertainty and check for overlapping accesses. | ||||||||
| 820 | struct AA::PointerInfo::OffsetAndSize : public std::pair<int64_t, int64_t> { | ||||||||
| 821 | using BaseTy = std::pair<int64_t, int64_t>; | ||||||||
| 822 | OffsetAndSize(int64_t Offset, int64_t Size) : BaseTy(Offset, Size) {} | ||||||||
| 823 | OffsetAndSize(const BaseTy &P) : BaseTy(P) {} | ||||||||
| 824 | int64_t getOffset() const { return first; } | ||||||||
| 825 | int64_t getSize() const { return second; } | ||||||||
| 826 | static OffsetAndSize getUnknown() { return OffsetAndSize(Unknown, Unknown); } | ||||||||
| 827 | |||||||||
| 828 | /// Return true if this offset and size pair might describe an address that | ||||||||
| 829 | /// overlaps with \p OAS. | ||||||||
| 830 | bool mayOverlap(const OffsetAndSize &OAS) const { | ||||||||
| 831 | // Any unknown value and we are giving up -> overlap. | ||||||||
| 832 | if (OAS.getOffset() == OffsetAndSize::Unknown || | ||||||||
| 833 | OAS.getSize() == OffsetAndSize::Unknown || | ||||||||
| 834 | getOffset() == OffsetAndSize::Unknown || | ||||||||
| 835 | getSize() == OffsetAndSize::Unknown) | ||||||||
| 836 | return true; | ||||||||
| 837 | |||||||||
| 838 | // Check if one offset point is in the other interval [offset, offset+size]. | ||||||||
| 839 | return OAS.getOffset() + OAS.getSize() > getOffset() && | ||||||||
| 840 | OAS.getOffset() < getOffset() + getSize(); | ||||||||
| 841 | } | ||||||||
| 842 | |||||||||
| 843 | /// Constant used to represent unknown offset or sizes. | ||||||||
| 844 | static constexpr int64_t Unknown = 1 << 31; | ||||||||
| 845 | }; | ||||||||
| 846 | |||||||||
| 847 | /// Implementation of the DenseMapInfo. | ||||||||
| 848 | /// | ||||||||
| 849 | ///{ | ||||||||
| 850 | inline llvm::AccessAsInstructionInfo::Access | ||||||||
| 851 | llvm::AccessAsInstructionInfo::getEmptyKey() { | ||||||||
| 852 | return Access(Base::getEmptyKey(), nullptr, AAPointerInfo::AK_READ, nullptr); | ||||||||
| 853 | } | ||||||||
| 854 | inline llvm::AccessAsInstructionInfo::Access | ||||||||
| 855 | llvm::AccessAsInstructionInfo::getTombstoneKey() { | ||||||||
| 856 | return Access(Base::getTombstoneKey(), nullptr, AAPointerInfo::AK_READ, | ||||||||
| 857 | nullptr); | ||||||||
| 858 | } | ||||||||
| 859 | unsigned llvm::AccessAsInstructionInfo::getHashValue( | ||||||||
| 860 | const llvm::AccessAsInstructionInfo::Access &A) { | ||||||||
| 861 | return Base::getHashValue(A.getRemoteInst()); | ||||||||
| 862 | } | ||||||||
| 863 | bool llvm::AccessAsInstructionInfo::isEqual( | ||||||||
| 864 | const llvm::AccessAsInstructionInfo::Access &LHS, | ||||||||
| 865 | const llvm::AccessAsInstructionInfo::Access &RHS) { | ||||||||
| 866 | return LHS.getRemoteInst() == RHS.getRemoteInst(); | ||||||||
| 867 | } | ||||||||
| 868 | inline llvm::DenseMapInfo<AAPointerInfo::Access>::Access | ||||||||
| 869 | llvm::DenseMapInfo<AAPointerInfo::Access>::getEmptyKey() { | ||||||||
| 870 | return AAPointerInfo::Access(nullptr, nullptr, AAPointerInfo::AK_READ, | ||||||||
| 871 | nullptr); | ||||||||
| 872 | } | ||||||||
| 873 | inline llvm::DenseMapInfo<AAPointerInfo::Access>::Access | ||||||||
| 874 | llvm::DenseMapInfo<AAPointerInfo::Access>::getTombstoneKey() { | ||||||||
| 875 | return AAPointerInfo::Access(nullptr, nullptr, AAPointerInfo::AK_WRITE, | ||||||||
| 876 | nullptr); | ||||||||
| 877 | } | ||||||||
| 878 | |||||||||
| 879 | unsigned llvm::DenseMapInfo<AAPointerInfo::Access>::getHashValue( | ||||||||
| 880 | const llvm::DenseMapInfo<AAPointerInfo::Access>::Access &A) { | ||||||||
| 881 | return detail::combineHashValue( | ||||||||
| 882 | DenseMapInfo<Instruction *>::getHashValue(A.getRemoteInst()), | ||||||||
| 883 | (A.isWrittenValueYetUndetermined() | ||||||||
| 884 | ? ~0 | ||||||||
| 885 | : DenseMapInfo<Value *>::getHashValue(A.getWrittenValue()))) + | ||||||||
| 886 | A.getKind(); | ||||||||
| 887 | } | ||||||||
| 888 | |||||||||
| 889 | bool llvm::DenseMapInfo<AAPointerInfo::Access>::isEqual( | ||||||||
| 890 | const llvm::DenseMapInfo<AAPointerInfo::Access>::Access &LHS, | ||||||||
| 891 | const llvm::DenseMapInfo<AAPointerInfo::Access>::Access &RHS) { | ||||||||
| 892 | return LHS == RHS; | ||||||||
| 893 | } | ||||||||
| 894 | ///} | ||||||||
| 895 | |||||||||
| 896 | /// A type to track pointer/struct usage and accesses for AAPointerInfo. | ||||||||
| 897 | struct AA::PointerInfo::State : public AbstractState { | ||||||||
| 898 | |||||||||
| 899 | /// Return the best possible representable state. | ||||||||
| 900 | static State getBestState(const State &SIS) { return State(); } | ||||||||
| 901 | |||||||||
| 902 | /// Return the worst possible representable state. | ||||||||
| 903 | static State getWorstState(const State &SIS) { | ||||||||
| 904 | State R; | ||||||||
| 905 | R.indicatePessimisticFixpoint(); | ||||||||
| 906 | return R; | ||||||||
| 907 | } | ||||||||
| 908 | |||||||||
| 909 | State() {} | ||||||||
| 910 | State(const State &SIS) : AccessBins(SIS.AccessBins) {} | ||||||||
| 911 | State(State &&SIS) : AccessBins(std::move(SIS.AccessBins)) {} | ||||||||
| 912 | |||||||||
| 913 | const State &getAssumed() const { return *this; } | ||||||||
| 914 | |||||||||
| 915 | /// See AbstractState::isValidState(). | ||||||||
| 916 | bool isValidState() const override { return BS.isValidState(); } | ||||||||
| 917 | |||||||||
| 918 | /// See AbstractState::isAtFixpoint(). | ||||||||
| 919 | bool isAtFixpoint() const override { return BS.isAtFixpoint(); } | ||||||||
| 920 | |||||||||
| 921 | /// See AbstractState::indicateOptimisticFixpoint(). | ||||||||
| 922 | ChangeStatus indicateOptimisticFixpoint() override { | ||||||||
| 923 | BS.indicateOptimisticFixpoint(); | ||||||||
| 924 | return ChangeStatus::UNCHANGED; | ||||||||
| 925 | } | ||||||||
| 926 | |||||||||
| 927 | /// See AbstractState::indicatePessimisticFixpoint(). | ||||||||
| 928 | ChangeStatus indicatePessimisticFixpoint() override { | ||||||||
| 929 | BS.indicatePessimisticFixpoint(); | ||||||||
| 930 | return ChangeStatus::CHANGED; | ||||||||
| 931 | } | ||||||||
| 932 | |||||||||
| 933 | State &operator=(const State &R) { | ||||||||
| 934 | if (this == &R) | ||||||||
| 935 | return *this; | ||||||||
| 936 | BS = R.BS; | ||||||||
| 937 | AccessBins = R.AccessBins; | ||||||||
| 938 | return *this; | ||||||||
| 939 | } | ||||||||
| 940 | |||||||||
| 941 | State &operator=(State &&R) { | ||||||||
| 942 | if (this == &R) | ||||||||
| 943 | return *this; | ||||||||
| 944 | std::swap(BS, R.BS); | ||||||||
| 945 | std::swap(AccessBins, R.AccessBins); | ||||||||
| 946 | return *this; | ||||||||
| 947 | } | ||||||||
| 948 | |||||||||
| 949 | bool operator==(const State &R) const { | ||||||||
| 950 | if (BS != R.BS) | ||||||||
| 951 | return false; | ||||||||
| 952 | if (AccessBins.size() != R.AccessBins.size()) | ||||||||
| 953 | return false; | ||||||||
| 954 | auto It = begin(), RIt = R.begin(), E = end(); | ||||||||
| 955 | while (It != E) { | ||||||||
| 956 | if (It->getFirst() != RIt->getFirst()) | ||||||||
| 957 | return false; | ||||||||
| 958 | auto &Accs = It->getSecond(); | ||||||||
| 959 | auto &RAccs = RIt->getSecond(); | ||||||||
| 960 | if (Accs.size() != RAccs.size()) | ||||||||
| 961 | return false; | ||||||||
| 962 | auto AccIt = Accs.begin(), RAccIt = RAccs.begin(), AccE = Accs.end(); | ||||||||
| 963 | while (AccIt != AccE) { | ||||||||
| 964 | if (*AccIt != *RAccIt) | ||||||||
| 965 | return false; | ||||||||
| 966 | ++AccIt; | ||||||||
| 967 | ++RAccIt; | ||||||||
| 968 | } | ||||||||
| 969 | ++It; | ||||||||
| 970 | ++RIt; | ||||||||
| 971 | } | ||||||||
| 972 | return true; | ||||||||
| 973 | } | ||||||||
| 974 | bool operator!=(const State &R) const { return !(*this == R); } | ||||||||
| 975 | |||||||||
| 976 | /// We store accesses in a set with the instruction as key. | ||||||||
| 977 | using Accesses = DenseSet<AAPointerInfo::Access, AccessAsInstructionInfo>; | ||||||||
| 978 | |||||||||
| 979 | /// We store all accesses in bins denoted by their offset and size. | ||||||||
| 980 | using AccessBinsTy = DenseMap<OffsetAndSize, Accesses>; | ||||||||
| 981 | |||||||||
| 982 | AccessBinsTy::const_iterator begin() const { return AccessBins.begin(); } | ||||||||
| 983 | AccessBinsTy::const_iterator end() const { return AccessBins.end(); } | ||||||||
| 984 | |||||||||
| 985 | protected: | ||||||||
| 986 | /// The bins with all the accesses for the associated pointer. | ||||||||
| 987 | DenseMap<OffsetAndSize, Accesses> AccessBins; | ||||||||
| 988 | |||||||||
| 989 | /// Add a new access to the state at offset \p Offset and with size \p Size. | ||||||||
| 990 | /// The access is associated with \p I, writes \p Content (if anything), and | ||||||||
| 991 | /// is of kind \p Kind. | ||||||||
| 992 | /// \Returns CHANGED, if the state changed, UNCHANGED otherwise. | ||||||||
| 993 | ChangeStatus addAccess(int64_t Offset, int64_t Size, Instruction &I, | ||||||||
| 994 | Optional<Value *> Content, | ||||||||
| 995 | AAPointerInfo::AccessKind Kind, Type *Ty, | ||||||||
| 996 | Instruction *RemoteI = nullptr, | ||||||||
| 997 | Accesses *BinPtr = nullptr) { | ||||||||
| 998 | OffsetAndSize Key{Offset, Size}; | ||||||||
| 999 | Accesses &Bin = BinPtr ? *BinPtr : AccessBins[Key]; | ||||||||
| 1000 | AAPointerInfo::Access Acc(&I, RemoteI ? RemoteI : &I, Content, Kind, Ty); | ||||||||
| 1001 | // Check if we have an access for this instruction in this bin, if not, | ||||||||
| 1002 | // simply add it. | ||||||||
| 1003 | auto It = Bin.find(Acc); | ||||||||
| 1004 | if (It == Bin.end()) { | ||||||||
| 1005 | Bin.insert(Acc); | ||||||||
| 1006 | return ChangeStatus::CHANGED; | ||||||||
| 1007 | } | ||||||||
| 1008 | // If the existing access is the same as then new one, nothing changed. | ||||||||
| 1009 | AAPointerInfo::Access Before = *It; | ||||||||
| 1010 | // The new one will be combined with the existing one. | ||||||||
| 1011 | *It &= Acc; | ||||||||
| 1012 | return *It == Before ? ChangeStatus::UNCHANGED : ChangeStatus::CHANGED; | ||||||||
| 1013 | } | ||||||||
| 1014 | |||||||||
| 1015 | /// See AAPointerInfo::forallInterferingAccesses. | ||||||||
| 1016 | bool forallInterferingAccesses( | ||||||||
| 1017 | Instruction &I, | ||||||||
| 1018 | function_ref<bool(const AAPointerInfo::Access &, bool)> CB) const { | ||||||||
| 1019 | if (!isValidState()) | ||||||||
| 1020 | return false; | ||||||||
| 1021 | // First find the offset and size of I. | ||||||||
| 1022 | OffsetAndSize OAS(-1, -1); | ||||||||
| 1023 | for (auto &It : AccessBins) { | ||||||||
| 1024 | for (auto &Access : It.getSecond()) { | ||||||||
| 1025 | if (Access.getRemoteInst() == &I) { | ||||||||
| 1026 | OAS = It.getFirst(); | ||||||||
| 1027 | break; | ||||||||
| 1028 | } | ||||||||
| 1029 | } | ||||||||
| 1030 | if (OAS.getSize() != -1) | ||||||||
| 1031 | break; | ||||||||
| 1032 | } | ||||||||
| 1033 | if (OAS.getSize() == -1) | ||||||||
| 1034 | return true; | ||||||||
| 1035 | |||||||||
| 1036 | // Now that we have an offset and size, find all overlapping ones and use | ||||||||
| 1037 | // the callback on the accesses. | ||||||||
| 1038 | for (auto &It : AccessBins) { | ||||||||
| 1039 | OffsetAndSize ItOAS = It.getFirst(); | ||||||||
| 1040 | if (!OAS.mayOverlap(ItOAS)) | ||||||||
| 1041 | continue; | ||||||||
| 1042 | for (auto &Access : It.getSecond()) | ||||||||
| 1043 | if (!CB(Access, OAS == ItOAS)) | ||||||||
| 1044 | return false; | ||||||||
| 1045 | } | ||||||||
| 1046 | return true; | ||||||||
| 1047 | } | ||||||||
| 1048 | |||||||||
| 1049 | private: | ||||||||
| 1050 | /// State to track fixpoint and validity. | ||||||||
| 1051 | BooleanState BS; | ||||||||
| 1052 | }; | ||||||||
| 1053 | |||||||||
| 1054 | struct AAPointerInfoImpl | ||||||||
| 1055 | : public StateWrapper<AA::PointerInfo::State, AAPointerInfo> { | ||||||||
| 1056 | using BaseTy = StateWrapper<AA::PointerInfo::State, AAPointerInfo>; | ||||||||
| 1057 | AAPointerInfoImpl(const IRPosition &IRP, Attributor &A) : BaseTy(IRP) {} | ||||||||
| 1058 | |||||||||
| 1059 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1060 | void initialize(Attributor &A) override { AAPointerInfo::initialize(A); } | ||||||||
| 1061 | |||||||||
| 1062 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 1063 | const std::string getAsStr() const override { | ||||||||
| 1064 | return std::string("PointerInfo ") + | ||||||||
| 1065 | (isValidState() ? (std::string("#") + | ||||||||
| 1066 | std::to_string(AccessBins.size()) + " bins") | ||||||||
| 1067 | : "<invalid>"); | ||||||||
| 1068 | } | ||||||||
| 1069 | |||||||||
| 1070 | /// See AbstractAttribute::manifest(...). | ||||||||
| 1071 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 1072 | return AAPointerInfo::manifest(A); | ||||||||
| 1073 | } | ||||||||
| 1074 | |||||||||
| 1075 | bool forallInterferingAccesses( | ||||||||
| 1076 | LoadInst &LI, function_ref<bool(const AAPointerInfo::Access &, bool)> CB) | ||||||||
| 1077 | const override { | ||||||||
| 1078 | return State::forallInterferingAccesses(LI, CB); | ||||||||
| 1079 | } | ||||||||
| 1080 | bool forallInterferingAccesses( | ||||||||
| 1081 | StoreInst &SI, function_ref<bool(const AAPointerInfo::Access &, bool)> CB) | ||||||||
| 1082 | const override { | ||||||||
| 1083 | return State::forallInterferingAccesses(SI, CB); | ||||||||
| 1084 | } | ||||||||
| 1085 | |||||||||
| 1086 | ChangeStatus translateAndAddCalleeState(Attributor &A, | ||||||||
| 1087 | const AAPointerInfo &CalleeAA, | ||||||||
| 1088 | int64_t CallArgOffset, CallBase &CB) { | ||||||||
| 1089 | using namespace AA::PointerInfo; | ||||||||
| 1090 | if (!CalleeAA.getState().isValidState() || !isValidState()) | ||||||||
| 1091 | return indicatePessimisticFixpoint(); | ||||||||
| 1092 | |||||||||
| 1093 | const auto &CalleeImplAA = static_cast<const AAPointerInfoImpl &>(CalleeAA); | ||||||||
| 1094 | bool IsByval = CalleeImplAA.getAssociatedArgument()->hasByValAttr(); | ||||||||
| 1095 | |||||||||
| 1096 | // Combine the accesses bin by bin. | ||||||||
| 1097 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 1098 | for (auto &It : CalleeImplAA.getState()) { | ||||||||
| 1099 | OffsetAndSize OAS = OffsetAndSize::getUnknown(); | ||||||||
| 1100 | if (CallArgOffset != OffsetAndSize::Unknown) | ||||||||
| 1101 | OAS = OffsetAndSize(It.first.getOffset() + CallArgOffset, | ||||||||
| 1102 | It.first.getSize()); | ||||||||
| 1103 | Accesses &Bin = AccessBins[OAS]; | ||||||||
| 1104 | for (const AAPointerInfo::Access &RAcc : It.second) { | ||||||||
| 1105 | if (IsByval && !RAcc.isRead()) | ||||||||
| 1106 | continue; | ||||||||
| 1107 | bool UsedAssumedInformation = false; | ||||||||
| 1108 | Optional<Value *> Content = A.translateArgumentToCallSiteContent( | ||||||||
| 1109 | RAcc.getContent(), CB, *this, UsedAssumedInformation); | ||||||||
| 1110 | AccessKind AK = | ||||||||
| 1111 | AccessKind(RAcc.getKind() & (IsByval ? AccessKind::AK_READ | ||||||||
| 1112 | : AccessKind::AK_READ_WRITE)); | ||||||||
| 1113 | Changed = | ||||||||
| 1114 | Changed | addAccess(OAS.getOffset(), OAS.getSize(), CB, Content, AK, | ||||||||
| 1115 | RAcc.getType(), RAcc.getRemoteInst(), &Bin); | ||||||||
| 1116 | } | ||||||||
| 1117 | } | ||||||||
| 1118 | return Changed; | ||||||||
| 1119 | } | ||||||||
| 1120 | |||||||||
| 1121 | /// Statistic tracking for all AAPointerInfo implementations. | ||||||||
| 1122 | /// See AbstractAttribute::trackStatistics(). | ||||||||
| 1123 | void trackPointerInfoStatistics(const IRPosition &IRP) const {} | ||||||||
| 1124 | }; | ||||||||
| 1125 | |||||||||
| 1126 | struct AAPointerInfoFloating : public AAPointerInfoImpl { | ||||||||
| 1127 | using AccessKind = AAPointerInfo::AccessKind; | ||||||||
| 1128 | AAPointerInfoFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 1129 | : AAPointerInfoImpl(IRP, A) {} | ||||||||
| 1130 | |||||||||
| 1131 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1132 | void initialize(Attributor &A) override { AAPointerInfoImpl::initialize(A); } | ||||||||
| 1133 | |||||||||
| 1134 | /// Deal with an access and signal if it was handled successfully. | ||||||||
| 1135 | bool handleAccess(Attributor &A, Instruction &I, Value &Ptr, | ||||||||
| 1136 | Optional<Value *> Content, AccessKind Kind, int64_t Offset, | ||||||||
| 1137 | ChangeStatus &Changed, Type *Ty, | ||||||||
| 1138 | int64_t Size = AA::PointerInfo::OffsetAndSize::Unknown) { | ||||||||
| 1139 | using namespace AA::PointerInfo; | ||||||||
| 1140 | // No need to find a size if one is given or the offset is unknown. | ||||||||
| 1141 | if (Offset != OffsetAndSize::Unknown && Size == OffsetAndSize::Unknown && | ||||||||
| 1142 | Ty) { | ||||||||
| 1143 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 1144 | TypeSize AccessSize = DL.getTypeStoreSize(Ty); | ||||||||
| 1145 | if (!AccessSize.isScalable()) | ||||||||
| 1146 | Size = AccessSize.getFixedSize(); | ||||||||
| 1147 | } | ||||||||
| 1148 | Changed = Changed | addAccess(Offset, Size, I, Content, Kind, Ty); | ||||||||
| 1149 | return true; | ||||||||
| 1150 | }; | ||||||||
| 1151 | |||||||||
| 1152 | /// Helper struct, will support ranges eventually. | ||||||||
| 1153 | struct OffsetInfo { | ||||||||
| 1154 | int64_t Offset = AA::PointerInfo::OffsetAndSize::Unknown; | ||||||||
| 1155 | |||||||||
| 1156 | bool operator==(const OffsetInfo &OI) const { return Offset == OI.Offset; } | ||||||||
| 1157 | }; | ||||||||
| 1158 | |||||||||
| 1159 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1160 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1161 | using namespace AA::PointerInfo; | ||||||||
| 1162 | State S = getState(); | ||||||||
| 1163 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 1164 | Value &AssociatedValue = getAssociatedValue(); | ||||||||
| 1165 | |||||||||
| 1166 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 1167 | DenseMap<Value *, OffsetInfo> OffsetInfoMap; | ||||||||
| 1168 | OffsetInfoMap[&AssociatedValue] = OffsetInfo{0}; | ||||||||
| 1169 | |||||||||
| 1170 | auto HandlePassthroughUser = [&](Value *Usr, OffsetInfo &PtrOI, | ||||||||
| 1171 | bool &Follow) { | ||||||||
| 1172 | OffsetInfo &UsrOI = OffsetInfoMap[Usr]; | ||||||||
| 1173 | UsrOI = PtrOI; | ||||||||
| 1174 | Follow = true; | ||||||||
| 1175 | return true; | ||||||||
| 1176 | }; | ||||||||
| 1177 | |||||||||
| 1178 | auto UsePred = [&](const Use &U, bool &Follow) -> bool { | ||||||||
| 1179 | Value *CurPtr = U.get(); | ||||||||
| 1180 | User *Usr = U.getUser(); | ||||||||
| 1181 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Analyze " << *CurPtr << " in "do { } while (false) | ||||||||
| 1182 | << *Usr << "\n")do { } while (false); | ||||||||
| 1183 | |||||||||
| 1184 | OffsetInfo &PtrOI = OffsetInfoMap[CurPtr]; | ||||||||
| 1185 | |||||||||
| 1186 | if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Usr)) { | ||||||||
| 1187 | if (CE->isCast()) | ||||||||
| 1188 | return HandlePassthroughUser(Usr, PtrOI, Follow); | ||||||||
| 1189 | if (CE->isCompare()) | ||||||||
| 1190 | return true; | ||||||||
| 1191 | if (!CE->isGEPWithNoNotionalOverIndexing()) { | ||||||||
| 1192 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Unhandled constant user " << *CEdo { } while (false) | ||||||||
| 1193 | << "\n")do { } while (false); | ||||||||
| 1194 | return false; | ||||||||
| 1195 | } | ||||||||
| 1196 | } | ||||||||
| 1197 | if (auto *GEP = dyn_cast<GEPOperator>(Usr)) { | ||||||||
| 1198 | OffsetInfo &UsrOI = OffsetInfoMap[Usr]; | ||||||||
| 1199 | UsrOI = PtrOI; | ||||||||
| 1200 | |||||||||
| 1201 | // TODO: Use range information. | ||||||||
| 1202 | if (PtrOI.Offset == OffsetAndSize::Unknown || | ||||||||
| 1203 | !GEP->hasAllConstantIndices()) { | ||||||||
| 1204 | UsrOI.Offset = OffsetAndSize::Unknown; | ||||||||
| 1205 | Follow = true; | ||||||||
| 1206 | return true; | ||||||||
| 1207 | } | ||||||||
| 1208 | |||||||||
| 1209 | SmallVector<Value *, 8> Indices; | ||||||||
| 1210 | for (Use &Idx : llvm::make_range(GEP->idx_begin(), GEP->idx_end())) { | ||||||||
| 1211 | if (auto *CIdx = dyn_cast<ConstantInt>(Idx)) { | ||||||||
| 1212 | Indices.push_back(CIdx); | ||||||||
| 1213 | continue; | ||||||||
| 1214 | } | ||||||||
| 1215 | |||||||||
| 1216 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Non constant GEP index " << *GEPdo { } while (false) | ||||||||
| 1217 | << " : " << *Idx << "\n")do { } while (false); | ||||||||
| 1218 | return false; | ||||||||
| 1219 | } | ||||||||
| 1220 | UsrOI.Offset = PtrOI.Offset + | ||||||||
| 1221 | DL.getIndexedOffsetInType( | ||||||||
| 1222 | CurPtr->getType()->getPointerElementType(), Indices); | ||||||||
| 1223 | Follow = true; | ||||||||
| 1224 | return true; | ||||||||
| 1225 | } | ||||||||
| 1226 | if (isa<CastInst>(Usr) || isa<SelectInst>(Usr)) | ||||||||
| 1227 | return HandlePassthroughUser(Usr, PtrOI, Follow); | ||||||||
| 1228 | |||||||||
| 1229 | // For PHIs we need to take care of the recurrence explicitly as the value | ||||||||
| 1230 | // might change while we iterate through a loop. For now, we give up if | ||||||||
| 1231 | // the PHI is not invariant. | ||||||||
| 1232 | if (isa<PHINode>(Usr)) { | ||||||||
| 1233 | // Check if the PHI is invariant (so far). | ||||||||
| 1234 | OffsetInfo &UsrOI = OffsetInfoMap[Usr]; | ||||||||
| 1235 | if (UsrOI == PtrOI) | ||||||||
| 1236 | return true; | ||||||||
| 1237 | |||||||||
| 1238 | // Check if the PHI operand has already an unknown offset as we can't | ||||||||
| 1239 | // improve on that anymore. | ||||||||
| 1240 | if (PtrOI.Offset == OffsetAndSize::Unknown) { | ||||||||
| 1241 | UsrOI = PtrOI; | ||||||||
| 1242 | Follow = true; | ||||||||
| 1243 | return true; | ||||||||
| 1244 | } | ||||||||
| 1245 | |||||||||
| 1246 | // Check if the PHI operand is not dependent on the PHI itself. | ||||||||
| 1247 | APInt Offset(DL.getIndexTypeSizeInBits(AssociatedValue.getType()), 0); | ||||||||
| 1248 | if (&AssociatedValue == CurPtr->stripAndAccumulateConstantOffsets( | ||||||||
| 1249 | DL, Offset, /* AllowNonInbounds */ true)) { | ||||||||
| 1250 | if (Offset != PtrOI.Offset) { | ||||||||
| 1251 | LLVM_DEBUG(dbgs()do { } while (false) | ||||||||
| 1252 | << "[AAPointerInfo] PHI operand pointer offset mismatch "do { } while (false) | ||||||||
| 1253 | << *CurPtr << " in " << *Usr << "\n")do { } while (false); | ||||||||
| 1254 | return false; | ||||||||
| 1255 | } | ||||||||
| 1256 | return HandlePassthroughUser(Usr, PtrOI, Follow); | ||||||||
| 1257 | } | ||||||||
| 1258 | |||||||||
| 1259 | // TODO: Approximate in case we know the direction of the recurrence. | ||||||||
| 1260 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] PHI operand is too complex "do { } while (false) | ||||||||
| 1261 | << *CurPtr << " in " << *Usr << "\n")do { } while (false); | ||||||||
| 1262 | UsrOI = PtrOI; | ||||||||
| 1263 | UsrOI.Offset = OffsetAndSize::Unknown; | ||||||||
| 1264 | Follow = true; | ||||||||
| 1265 | return true; | ||||||||
| 1266 | } | ||||||||
| 1267 | |||||||||
| 1268 | if (auto *LoadI = dyn_cast<LoadInst>(Usr)) | ||||||||
| 1269 | return handleAccess(A, *LoadI, *CurPtr, /* Content */ nullptr, | ||||||||
| 1270 | AccessKind::AK_READ, PtrOI.Offset, Changed, | ||||||||
| 1271 | LoadI->getType()); | ||||||||
| 1272 | if (auto *StoreI = dyn_cast<StoreInst>(Usr)) { | ||||||||
| 1273 | if (StoreI->getValueOperand() == CurPtr) { | ||||||||
| 1274 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Escaping use in store "do { } while (false) | ||||||||
| 1275 | << *StoreI << "\n")do { } while (false); | ||||||||
| 1276 | return false; | ||||||||
| 1277 | } | ||||||||
| 1278 | bool UsedAssumedInformation = false; | ||||||||
| 1279 | Optional<Value *> Content = A.getAssumedSimplified( | ||||||||
| 1280 | *StoreI->getValueOperand(), *this, UsedAssumedInformation); | ||||||||
| 1281 | return handleAccess(A, *StoreI, *CurPtr, Content, AccessKind::AK_WRITE, | ||||||||
| 1282 | PtrOI.Offset, Changed, | ||||||||
| 1283 | StoreI->getValueOperand()->getType()); | ||||||||
| 1284 | } | ||||||||
| 1285 | if (auto *CB = dyn_cast<CallBase>(Usr)) { | ||||||||
| 1286 | if (CB->isLifetimeStartOrEnd()) | ||||||||
| 1287 | return true; | ||||||||
| 1288 | if (CB->isArgOperand(&U)) { | ||||||||
| 1289 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||||||
| 1290 | const auto &CSArgPI = A.getAAFor<AAPointerInfo>( | ||||||||
| 1291 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||||||
| 1292 | DepClassTy::REQUIRED); | ||||||||
| 1293 | Changed = translateAndAddCalleeState(A, CSArgPI, PtrOI.Offset, *CB) | | ||||||||
| 1294 | Changed; | ||||||||
| 1295 | return true; | ||||||||
| 1296 | } | ||||||||
| 1297 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Call user not handled " << *CBdo { } while (false) | ||||||||
| 1298 | << "\n")do { } while (false); | ||||||||
| 1299 | // TODO: Allow some call uses | ||||||||
| 1300 | return false; | ||||||||
| 1301 | } | ||||||||
| 1302 | |||||||||
| 1303 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] User not handled " << *Usr << "\n")do { } while (false); | ||||||||
| 1304 | return false; | ||||||||
| 1305 | }; | ||||||||
| 1306 | if (!A.checkForAllUses(UsePred, *this, AssociatedValue, | ||||||||
| 1307 | /* CheckBBLivenessOnly */ true)) | ||||||||
| 1308 | return indicatePessimisticFixpoint(); | ||||||||
| 1309 | |||||||||
| 1310 | LLVM_DEBUG({do { } while (false) | ||||||||
| 1311 | dbgs() << "Accesses by bin after update:\n";do { } while (false) | ||||||||
| 1312 | for (auto &It : AccessBins) {do { } while (false) | ||||||||
| 1313 | dbgs() << "[" << It.first.getOffset() << "-"do { } while (false) | ||||||||
| 1314 | << It.first.getOffset() + It.first.getSize()do { } while (false) | ||||||||
| 1315 | << "] : " << It.getSecond().size() << "\n";do { } while (false) | ||||||||
| 1316 | for (auto &Acc : It.getSecond()) {do { } while (false) | ||||||||
| 1317 | dbgs() << " - " << Acc.getKind() << " - " << *Acc.getLocalInst()do { } while (false) | ||||||||
| 1318 | << "\n";do { } while (false) | ||||||||
| 1319 | if (Acc.getLocalInst() != Acc.getRemoteInst())do { } while (false) | ||||||||
| 1320 | dbgs() << " --> "do { } while (false) | ||||||||
| 1321 | << *Acc.getRemoteInst() << "\n";do { } while (false) | ||||||||
| 1322 | if (!Acc.isWrittenValueYetUndetermined())do { } while (false) | ||||||||
| 1323 | dbgs() << " - " << Acc.getWrittenValue() << "\n";do { } while (false) | ||||||||
| 1324 | }do { } while (false) | ||||||||
| 1325 | }do { } while (false) | ||||||||
| 1326 | })do { } while (false); | ||||||||
| 1327 | |||||||||
| 1328 | return Changed; | ||||||||
| 1329 | } | ||||||||
| 1330 | |||||||||
| 1331 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1332 | void trackStatistics() const override { | ||||||||
| 1333 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||||||
| 1334 | } | ||||||||
| 1335 | }; | ||||||||
| 1336 | |||||||||
| 1337 | struct AAPointerInfoReturned final : AAPointerInfoImpl { | ||||||||
| 1338 | AAPointerInfoReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 1339 | : AAPointerInfoImpl(IRP, A) {} | ||||||||
| 1340 | |||||||||
| 1341 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1342 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1343 | return indicatePessimisticFixpoint(); | ||||||||
| 1344 | } | ||||||||
| 1345 | |||||||||
| 1346 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1347 | void trackStatistics() const override { | ||||||||
| 1348 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||||||
| 1349 | } | ||||||||
| 1350 | }; | ||||||||
| 1351 | |||||||||
| 1352 | struct AAPointerInfoArgument final : AAPointerInfoFloating { | ||||||||
| 1353 | AAPointerInfoArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 1354 | : AAPointerInfoFloating(IRP, A) {} | ||||||||
| 1355 | |||||||||
| 1356 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1357 | void initialize(Attributor &A) override { | ||||||||
| 1358 | AAPointerInfoFloating::initialize(A); | ||||||||
| 1359 | if (getAnchorScope()->isDeclaration()) | ||||||||
| 1360 | indicatePessimisticFixpoint(); | ||||||||
| 1361 | } | ||||||||
| 1362 | |||||||||
| 1363 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1364 | void trackStatistics() const override { | ||||||||
| 1365 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||||||
| 1366 | } | ||||||||
| 1367 | }; | ||||||||
| 1368 | |||||||||
| 1369 | struct AAPointerInfoCallSiteArgument final : AAPointerInfoFloating { | ||||||||
| 1370 | AAPointerInfoCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 1371 | : AAPointerInfoFloating(IRP, A) {} | ||||||||
| 1372 | |||||||||
| 1373 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1374 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1375 | using namespace AA::PointerInfo; | ||||||||
| 1376 | // We handle memory intrinsics explicitly, at least the first (= | ||||||||
| 1377 | // destination) and second (=source) arguments as we know how they are | ||||||||
| 1378 | // accessed. | ||||||||
| 1379 | if (auto *MI = dyn_cast_or_null<MemIntrinsic>(getCtxI())) { | ||||||||
| 1380 | ConstantInt *Length = dyn_cast<ConstantInt>(MI->getLength()); | ||||||||
| 1381 | int64_t LengthVal = OffsetAndSize::Unknown; | ||||||||
| 1382 | if (Length) | ||||||||
| 1383 | LengthVal = Length->getSExtValue(); | ||||||||
| 1384 | Value &Ptr = getAssociatedValue(); | ||||||||
| 1385 | unsigned ArgNo = getIRPosition().getCallSiteArgNo(); | ||||||||
| 1386 | ChangeStatus Changed; | ||||||||
| 1387 | if (ArgNo == 0) { | ||||||||
| 1388 | handleAccess(A, *MI, Ptr, nullptr, AccessKind::AK_WRITE, 0, Changed, | ||||||||
| 1389 | nullptr, LengthVal); | ||||||||
| 1390 | } else if (ArgNo == 1) { | ||||||||
| 1391 | handleAccess(A, *MI, Ptr, nullptr, AccessKind::AK_READ, 0, Changed, | ||||||||
| 1392 | nullptr, LengthVal); | ||||||||
| 1393 | } else { | ||||||||
| 1394 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Unhandled memory intrinsic "do { } while (false) | ||||||||
| 1395 | << *MI << "\n")do { } while (false); | ||||||||
| 1396 | return indicatePessimisticFixpoint(); | ||||||||
| 1397 | } | ||||||||
| 1398 | return Changed; | ||||||||
| 1399 | } | ||||||||
| 1400 | |||||||||
| 1401 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 1402 | // call site specific liveness information and then it makes | ||||||||
| 1403 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 1404 | // redirecting requests to the callee argument. | ||||||||
| 1405 | Argument *Arg = getAssociatedArgument(); | ||||||||
| 1406 | if (!Arg) | ||||||||
| 1407 | return indicatePessimisticFixpoint(); | ||||||||
| 1408 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||||||
| 1409 | auto &ArgAA = | ||||||||
| 1410 | A.getAAFor<AAPointerInfo>(*this, ArgPos, DepClassTy::REQUIRED); | ||||||||
| 1411 | return translateAndAddCalleeState(A, ArgAA, 0, *cast<CallBase>(getCtxI())); | ||||||||
| 1412 | } | ||||||||
| 1413 | |||||||||
| 1414 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1415 | void trackStatistics() const override { | ||||||||
| 1416 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||||||
| 1417 | } | ||||||||
| 1418 | }; | ||||||||
| 1419 | |||||||||
| 1420 | struct AAPointerInfoCallSiteReturned final : AAPointerInfoFloating { | ||||||||
| 1421 | AAPointerInfoCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 1422 | : AAPointerInfoFloating(IRP, A) {} | ||||||||
| 1423 | |||||||||
| 1424 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1425 | void trackStatistics() const override { | ||||||||
| 1426 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||||||
| 1427 | } | ||||||||
| 1428 | }; | ||||||||
| 1429 | |||||||||
| 1430 | /// -----------------------NoUnwind Function Attribute-------------------------- | ||||||||
| 1431 | |||||||||
| 1432 | struct AANoUnwindImpl : AANoUnwind { | ||||||||
| 1433 | AANoUnwindImpl(const IRPosition &IRP, Attributor &A) : AANoUnwind(IRP, A) {} | ||||||||
| 1434 | |||||||||
| 1435 | const std::string getAsStr() const override { | ||||||||
| 1436 | return getAssumed() ? "nounwind" : "may-unwind"; | ||||||||
| 1437 | } | ||||||||
| 1438 | |||||||||
| 1439 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1440 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1441 | auto Opcodes = { | ||||||||
| 1442 | (unsigned)Instruction::Invoke, (unsigned)Instruction::CallBr, | ||||||||
| 1443 | (unsigned)Instruction::Call, (unsigned)Instruction::CleanupRet, | ||||||||
| 1444 | (unsigned)Instruction::CatchSwitch, (unsigned)Instruction::Resume}; | ||||||||
| 1445 | |||||||||
| 1446 | auto CheckForNoUnwind = [&](Instruction &I) { | ||||||||
| 1447 | if (!I.mayThrow()) | ||||||||
| 1448 | return true; | ||||||||
| 1449 | |||||||||
| 1450 | if (const auto *CB = dyn_cast<CallBase>(&I)) { | ||||||||
| 1451 | const auto &NoUnwindAA = A.getAAFor<AANoUnwind>( | ||||||||
| 1452 | *this, IRPosition::callsite_function(*CB), DepClassTy::REQUIRED); | ||||||||
| 1453 | return NoUnwindAA.isAssumedNoUnwind(); | ||||||||
| 1454 | } | ||||||||
| 1455 | return false; | ||||||||
| 1456 | }; | ||||||||
| 1457 | |||||||||
| 1458 | bool UsedAssumedInformation = false; | ||||||||
| 1459 | if (!A.checkForAllInstructions(CheckForNoUnwind, *this, Opcodes, | ||||||||
| 1460 | UsedAssumedInformation)) | ||||||||
| 1461 | return indicatePessimisticFixpoint(); | ||||||||
| 1462 | |||||||||
| 1463 | return ChangeStatus::UNCHANGED; | ||||||||
| 1464 | } | ||||||||
| 1465 | }; | ||||||||
| 1466 | |||||||||
| 1467 | struct AANoUnwindFunction final : public AANoUnwindImpl { | ||||||||
| 1468 | AANoUnwindFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 1469 | : AANoUnwindImpl(IRP, A) {} | ||||||||
| 1470 | |||||||||
| 1471 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1472 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(nounwind){ static llvm::Statistic NumIRFunction_nounwind = {"attributor" , "NumIRFunction_nounwind", ("Number of " "functions" " marked '" "nounwind" "'")};; ++(NumIRFunction_nounwind); } } | ||||||||
| 1473 | }; | ||||||||
| 1474 | |||||||||
| 1475 | /// NoUnwind attribute deduction for a call sites. | ||||||||
| 1476 | struct AANoUnwindCallSite final : AANoUnwindImpl { | ||||||||
| 1477 | AANoUnwindCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 1478 | : AANoUnwindImpl(IRP, A) {} | ||||||||
| 1479 | |||||||||
| 1480 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1481 | void initialize(Attributor &A) override { | ||||||||
| 1482 | AANoUnwindImpl::initialize(A); | ||||||||
| 1483 | Function *F = getAssociatedFunction(); | ||||||||
| 1484 | if (!F || F->isDeclaration()) | ||||||||
| 1485 | indicatePessimisticFixpoint(); | ||||||||
| 1486 | } | ||||||||
| 1487 | |||||||||
| 1488 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1489 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1490 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 1491 | // call site specific liveness information and then it makes | ||||||||
| 1492 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 1493 | // redirecting requests to the callee argument. | ||||||||
| 1494 | Function *F = getAssociatedFunction(); | ||||||||
| 1495 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 1496 | auto &FnAA = A.getAAFor<AANoUnwind>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 1497 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 1498 | } | ||||||||
| 1499 | |||||||||
| 1500 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1501 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(nounwind){ static llvm::Statistic NumIRCS_nounwind = {"attributor", "NumIRCS_nounwind" , ("Number of " "call site" " marked '" "nounwind" "'")};; ++ (NumIRCS_nounwind); }; } | ||||||||
| 1502 | }; | ||||||||
| 1503 | |||||||||
| 1504 | /// --------------------- Function Return Values ------------------------------- | ||||||||
| 1505 | |||||||||
| 1506 | /// "Attribute" that collects all potential returned values and the return | ||||||||
| 1507 | /// instructions that they arise from. | ||||||||
| 1508 | /// | ||||||||
| 1509 | /// If there is a unique returned value R, the manifest method will: | ||||||||
| 1510 | /// - mark R with the "returned" attribute, if R is an argument. | ||||||||
| 1511 | class AAReturnedValuesImpl : public AAReturnedValues, public AbstractState { | ||||||||
| 1512 | |||||||||
| 1513 | /// Mapping of values potentially returned by the associated function to the | ||||||||
| 1514 | /// return instructions that might return them. | ||||||||
| 1515 | MapVector<Value *, SmallSetVector<ReturnInst *, 4>> ReturnedValues; | ||||||||
| 1516 | |||||||||
| 1517 | /// State flags | ||||||||
| 1518 | /// | ||||||||
| 1519 | ///{ | ||||||||
| 1520 | bool IsFixed = false; | ||||||||
| 1521 | bool IsValidState = true; | ||||||||
| 1522 | ///} | ||||||||
| 1523 | |||||||||
| 1524 | public: | ||||||||
| 1525 | AAReturnedValuesImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 1526 | : AAReturnedValues(IRP, A) {} | ||||||||
| 1527 | |||||||||
| 1528 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1529 | void initialize(Attributor &A) override { | ||||||||
| 1530 | // Reset the state. | ||||||||
| 1531 | IsFixed = false; | ||||||||
| 1532 | IsValidState = true; | ||||||||
| 1533 | ReturnedValues.clear(); | ||||||||
| 1534 | |||||||||
| 1535 | Function *F = getAssociatedFunction(); | ||||||||
| 1536 | if (!F || F->isDeclaration()) { | ||||||||
| 1537 | indicatePessimisticFixpoint(); | ||||||||
| 1538 | return; | ||||||||
| 1539 | } | ||||||||
| 1540 | assert(!F->getReturnType()->isVoidTy() &&((void)0) | ||||||||
| 1541 | "Did not expect a void return type!")((void)0); | ||||||||
| 1542 | |||||||||
| 1543 | // The map from instruction opcodes to those instructions in the function. | ||||||||
| 1544 | auto &OpcodeInstMap = A.getInfoCache().getOpcodeInstMapForFunction(*F); | ||||||||
| 1545 | |||||||||
| 1546 | // Look through all arguments, if one is marked as returned we are done. | ||||||||
| 1547 | for (Argument &Arg : F->args()) { | ||||||||
| 1548 | if (Arg.hasReturnedAttr()) { | ||||||||
| 1549 | auto &ReturnInstSet = ReturnedValues[&Arg]; | ||||||||
| 1550 | if (auto *Insts = OpcodeInstMap.lookup(Instruction::Ret)) | ||||||||
| 1551 | for (Instruction *RI : *Insts) | ||||||||
| 1552 | ReturnInstSet.insert(cast<ReturnInst>(RI)); | ||||||||
| 1553 | |||||||||
| 1554 | indicateOptimisticFixpoint(); | ||||||||
| 1555 | return; | ||||||||
| 1556 | } | ||||||||
| 1557 | } | ||||||||
| 1558 | |||||||||
| 1559 | if (!A.isFunctionIPOAmendable(*F)) | ||||||||
| 1560 | indicatePessimisticFixpoint(); | ||||||||
| 1561 | } | ||||||||
| 1562 | |||||||||
| 1563 | /// See AbstractAttribute::manifest(...). | ||||||||
| 1564 | ChangeStatus manifest(Attributor &A) override; | ||||||||
| 1565 | |||||||||
| 1566 | /// See AbstractAttribute::getState(...). | ||||||||
| 1567 | AbstractState &getState() override { return *this; } | ||||||||
| 1568 | |||||||||
| 1569 | /// See AbstractAttribute::getState(...). | ||||||||
| 1570 | const AbstractState &getState() const override { return *this; } | ||||||||
| 1571 | |||||||||
| 1572 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||||||
| 1573 | ChangeStatus updateImpl(Attributor &A) override; | ||||||||
| 1574 | |||||||||
| 1575 | llvm::iterator_range<iterator> returned_values() override { | ||||||||
| 1576 | return llvm::make_range(ReturnedValues.begin(), ReturnedValues.end()); | ||||||||
| 1577 | } | ||||||||
| 1578 | |||||||||
| 1579 | llvm::iterator_range<const_iterator> returned_values() const override { | ||||||||
| 1580 | return llvm::make_range(ReturnedValues.begin(), ReturnedValues.end()); | ||||||||
| 1581 | } | ||||||||
| 1582 | |||||||||
| 1583 | /// Return the number of potential return values, -1 if unknown. | ||||||||
| 1584 | size_t getNumReturnValues() const override { | ||||||||
| 1585 | return isValidState() ? ReturnedValues.size() : -1; | ||||||||
| 1586 | } | ||||||||
| 1587 | |||||||||
| 1588 | /// Return an assumed unique return value if a single candidate is found. If | ||||||||
| 1589 | /// there cannot be one, return a nullptr. If it is not clear yet, return the | ||||||||
| 1590 | /// Optional::NoneType. | ||||||||
| 1591 | Optional<Value *> getAssumedUniqueReturnValue(Attributor &A) const; | ||||||||
| 1592 | |||||||||
| 1593 | /// See AbstractState::checkForAllReturnedValues(...). | ||||||||
| 1594 | bool checkForAllReturnedValuesAndReturnInsts( | ||||||||
| 1595 | function_ref<bool(Value &, const SmallSetVector<ReturnInst *, 4> &)> Pred) | ||||||||
| 1596 | const override; | ||||||||
| 1597 | |||||||||
| 1598 | /// Pretty print the attribute similar to the IR representation. | ||||||||
| 1599 | const std::string getAsStr() const override; | ||||||||
| 1600 | |||||||||
| 1601 | /// See AbstractState::isAtFixpoint(). | ||||||||
| 1602 | bool isAtFixpoint() const override { return IsFixed; } | ||||||||
| 1603 | |||||||||
| 1604 | /// See AbstractState::isValidState(). | ||||||||
| 1605 | bool isValidState() const override { return IsValidState; } | ||||||||
| 1606 | |||||||||
| 1607 | /// See AbstractState::indicateOptimisticFixpoint(...). | ||||||||
| 1608 | ChangeStatus indicateOptimisticFixpoint() override { | ||||||||
| 1609 | IsFixed = true; | ||||||||
| 1610 | return ChangeStatus::UNCHANGED; | ||||||||
| 1611 | } | ||||||||
| 1612 | |||||||||
| 1613 | ChangeStatus indicatePessimisticFixpoint() override { | ||||||||
| 1614 | IsFixed = true; | ||||||||
| 1615 | IsValidState = false; | ||||||||
| 1616 | return ChangeStatus::CHANGED; | ||||||||
| 1617 | } | ||||||||
| 1618 | }; | ||||||||
| 1619 | |||||||||
| 1620 | ChangeStatus AAReturnedValuesImpl::manifest(Attributor &A) { | ||||||||
| 1621 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 1622 | |||||||||
| 1623 | // Bookkeeping. | ||||||||
| 1624 | assert(isValidState())((void)0); | ||||||||
| 1625 | STATS_DECLTRACK(KnownReturnValues, FunctionReturn,{ static llvm::Statistic NumIRFunctionReturn_KnownReturnValues = {"attributor", "NumIRFunctionReturn_KnownReturnValues", "Number of function with known return values" };; ++(NumIRFunctionReturn_KnownReturnValues); } | ||||||||
| 1626 | "Number of function with known return values"){ static llvm::Statistic NumIRFunctionReturn_KnownReturnValues = {"attributor", "NumIRFunctionReturn_KnownReturnValues", "Number of function with known return values" };; ++(NumIRFunctionReturn_KnownReturnValues); }; | ||||||||
| 1627 | |||||||||
| 1628 | // Check if we have an assumed unique return value that we could manifest. | ||||||||
| 1629 | Optional<Value *> UniqueRV = getAssumedUniqueReturnValue(A); | ||||||||
| 1630 | |||||||||
| 1631 | if (!UniqueRV.hasValue() || !UniqueRV.getValue()) | ||||||||
| 1632 | return Changed; | ||||||||
| 1633 | |||||||||
| 1634 | // Bookkeeping. | ||||||||
| 1635 | STATS_DECLTRACK(UniqueReturnValue, FunctionReturn,{ static llvm::Statistic NumIRFunctionReturn_UniqueReturnValue = {"attributor", "NumIRFunctionReturn_UniqueReturnValue", "Number of function with unique return" };; ++(NumIRFunctionReturn_UniqueReturnValue); } | ||||||||
| 1636 | "Number of function with unique return"){ static llvm::Statistic NumIRFunctionReturn_UniqueReturnValue = {"attributor", "NumIRFunctionReturn_UniqueReturnValue", "Number of function with unique return" };; ++(NumIRFunctionReturn_UniqueReturnValue); }; | ||||||||
| 1637 | // If the assumed unique return value is an argument, annotate it. | ||||||||
| 1638 | if (auto *UniqueRVArg = dyn_cast<Argument>(UniqueRV.getValue())) { | ||||||||
| 1639 | if (UniqueRVArg->getType()->canLosslesslyBitCastTo( | ||||||||
| 1640 | getAssociatedFunction()->getReturnType())) { | ||||||||
| 1641 | getIRPosition() = IRPosition::argument(*UniqueRVArg); | ||||||||
| 1642 | Changed = IRAttribute::manifest(A); | ||||||||
| 1643 | } | ||||||||
| 1644 | } | ||||||||
| 1645 | return Changed; | ||||||||
| 1646 | } | ||||||||
| 1647 | |||||||||
| 1648 | const std::string AAReturnedValuesImpl::getAsStr() const { | ||||||||
| 1649 | return (isAtFixpoint() ? "returns(#" : "may-return(#") + | ||||||||
| 1650 | (isValidState() ? std::to_string(getNumReturnValues()) : "?") + ")"; | ||||||||
| 1651 | } | ||||||||
| 1652 | |||||||||
| 1653 | Optional<Value *> | ||||||||
| 1654 | AAReturnedValuesImpl::getAssumedUniqueReturnValue(Attributor &A) const { | ||||||||
| 1655 | // If checkForAllReturnedValues provides a unique value, ignoring potential | ||||||||
| 1656 | // undef values that can also be present, it is assumed to be the actual | ||||||||
| 1657 | // return value and forwarded to the caller of this method. If there are | ||||||||
| 1658 | // multiple, a nullptr is returned indicating there cannot be a unique | ||||||||
| 1659 | // returned value. | ||||||||
| 1660 | Optional<Value *> UniqueRV; | ||||||||
| 1661 | Type *Ty = getAssociatedFunction()->getReturnType(); | ||||||||
| 1662 | |||||||||
| 1663 | auto Pred = [&](Value &RV) -> bool { | ||||||||
| 1664 | UniqueRV = AA::combineOptionalValuesInAAValueLatice(UniqueRV, &RV, Ty); | ||||||||
| 1665 | return UniqueRV != Optional<Value *>(nullptr); | ||||||||
| 1666 | }; | ||||||||
| 1667 | |||||||||
| 1668 | if (!A.checkForAllReturnedValues(Pred, *this)) | ||||||||
| 1669 | UniqueRV = nullptr; | ||||||||
| 1670 | |||||||||
| 1671 | return UniqueRV; | ||||||||
| 1672 | } | ||||||||
| 1673 | |||||||||
| 1674 | bool AAReturnedValuesImpl::checkForAllReturnedValuesAndReturnInsts( | ||||||||
| 1675 | function_ref<bool(Value &, const SmallSetVector<ReturnInst *, 4> &)> Pred) | ||||||||
| 1676 | const { | ||||||||
| 1677 | if (!isValidState()) | ||||||||
| 1678 | return false; | ||||||||
| 1679 | |||||||||
| 1680 | // Check all returned values but ignore call sites as long as we have not | ||||||||
| 1681 | // encountered an overdefined one during an update. | ||||||||
| 1682 | for (auto &It : ReturnedValues) { | ||||||||
| 1683 | Value *RV = It.first; | ||||||||
| 1684 | if (!Pred(*RV, It.second)) | ||||||||
| 1685 | return false; | ||||||||
| 1686 | } | ||||||||
| 1687 | |||||||||
| 1688 | return true; | ||||||||
| 1689 | } | ||||||||
| 1690 | |||||||||
| 1691 | ChangeStatus AAReturnedValuesImpl::updateImpl(Attributor &A) { | ||||||||
| 1692 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 1693 | |||||||||
| 1694 | auto ReturnValueCB = [&](Value &V, const Instruction *CtxI, ReturnInst &Ret, | ||||||||
| 1695 | bool) -> bool { | ||||||||
| 1696 | bool UsedAssumedInformation = false; | ||||||||
| 1697 | Optional<Value *> SimpleRetVal = | ||||||||
| 1698 | A.getAssumedSimplified(V, *this, UsedAssumedInformation); | ||||||||
| 1699 | if (!SimpleRetVal.hasValue()) | ||||||||
| 1700 | return true; | ||||||||
| 1701 | if (!SimpleRetVal.getValue()) | ||||||||
| 1702 | return false; | ||||||||
| 1703 | Value *RetVal = *SimpleRetVal; | ||||||||
| 1704 | assert(AA::isValidInScope(*RetVal, Ret.getFunction()) &&((void)0) | ||||||||
| 1705 | "Assumed returned value should be valid in function scope!")((void)0); | ||||||||
| 1706 | if (ReturnedValues[RetVal].insert(&Ret)) | ||||||||
| 1707 | Changed = ChangeStatus::CHANGED; | ||||||||
| 1708 | return true; | ||||||||
| 1709 | }; | ||||||||
| 1710 | |||||||||
| 1711 | auto ReturnInstCB = [&](Instruction &I) { | ||||||||
| 1712 | ReturnInst &Ret = cast<ReturnInst>(I); | ||||||||
| 1713 | return genericValueTraversal<ReturnInst>( | ||||||||
| 1714 | A, IRPosition::value(*Ret.getReturnValue()), *this, Ret, ReturnValueCB, | ||||||||
| 1715 | &I); | ||||||||
| 1716 | }; | ||||||||
| 1717 | |||||||||
| 1718 | // Discover returned values from all live returned instructions in the | ||||||||
| 1719 | // associated function. | ||||||||
| 1720 | bool UsedAssumedInformation = false; | ||||||||
| 1721 | if (!A.checkForAllInstructions(ReturnInstCB, *this, {Instruction::Ret}, | ||||||||
| 1722 | UsedAssumedInformation)) | ||||||||
| 1723 | return indicatePessimisticFixpoint(); | ||||||||
| 1724 | return Changed; | ||||||||
| 1725 | } | ||||||||
| 1726 | |||||||||
| 1727 | struct AAReturnedValuesFunction final : public AAReturnedValuesImpl { | ||||||||
| 1728 | AAReturnedValuesFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 1729 | : AAReturnedValuesImpl(IRP, A) {} | ||||||||
| 1730 | |||||||||
| 1731 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1732 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(returned){ static llvm::Statistic NumIRArguments_returned = {"attributor" , "NumIRArguments_returned", ("Number of " "arguments" " marked '" "returned" "'")};; ++(NumIRArguments_returned); } } | ||||||||
| 1733 | }; | ||||||||
| 1734 | |||||||||
| 1735 | /// Returned values information for a call sites. | ||||||||
| 1736 | struct AAReturnedValuesCallSite final : AAReturnedValuesImpl { | ||||||||
| 1737 | AAReturnedValuesCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 1738 | : AAReturnedValuesImpl(IRP, A) {} | ||||||||
| 1739 | |||||||||
| 1740 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1741 | void initialize(Attributor &A) override { | ||||||||
| 1742 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 1743 | // call site specific liveness information and then it makes | ||||||||
| 1744 | // sense to specialize attributes for call sites instead of | ||||||||
| 1745 | // redirecting requests to the callee. | ||||||||
| 1746 | llvm_unreachable("Abstract attributes for returned values are not "__builtin_unreachable() | ||||||||
| 1747 | "supported for call sites yet!")__builtin_unreachable(); | ||||||||
| 1748 | } | ||||||||
| 1749 | |||||||||
| 1750 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1751 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1752 | return indicatePessimisticFixpoint(); | ||||||||
| 1753 | } | ||||||||
| 1754 | |||||||||
| 1755 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1756 | void trackStatistics() const override {} | ||||||||
| 1757 | }; | ||||||||
| 1758 | |||||||||
| 1759 | /// ------------------------ NoSync Function Attribute ------------------------- | ||||||||
| 1760 | |||||||||
| 1761 | struct AANoSyncImpl : AANoSync { | ||||||||
| 1762 | AANoSyncImpl(const IRPosition &IRP, Attributor &A) : AANoSync(IRP, A) {} | ||||||||
| 1763 | |||||||||
| 1764 | const std::string getAsStr() const override { | ||||||||
| 1765 | return getAssumed() ? "nosync" : "may-sync"; | ||||||||
| 1766 | } | ||||||||
| 1767 | |||||||||
| 1768 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1769 | ChangeStatus updateImpl(Attributor &A) override; | ||||||||
| 1770 | |||||||||
| 1771 | /// Helper function used to determine whether an instruction is non-relaxed | ||||||||
| 1772 | /// atomic. In other words, if an atomic instruction does not have unordered | ||||||||
| 1773 | /// or monotonic ordering | ||||||||
| 1774 | static bool isNonRelaxedAtomic(Instruction *I); | ||||||||
| 1775 | |||||||||
| 1776 | /// Helper function specific for intrinsics which are potentially volatile | ||||||||
| 1777 | static bool isNoSyncIntrinsic(Instruction *I); | ||||||||
| 1778 | }; | ||||||||
| 1779 | |||||||||
| 1780 | bool AANoSyncImpl::isNonRelaxedAtomic(Instruction *I) { | ||||||||
| 1781 | if (!I->isAtomic()) | ||||||||
| 1782 | return false; | ||||||||
| 1783 | |||||||||
| 1784 | if (auto *FI = dyn_cast<FenceInst>(I)) | ||||||||
| 1785 | // All legal orderings for fence are stronger than monotonic. | ||||||||
| 1786 | return FI->getSyncScopeID() != SyncScope::SingleThread; | ||||||||
| 1787 | else if (auto *AI = dyn_cast<AtomicCmpXchgInst>(I)) { | ||||||||
| 1788 | // Unordered is not a legal ordering for cmpxchg. | ||||||||
| 1789 | return (AI->getSuccessOrdering() != AtomicOrdering::Monotonic || | ||||||||
| 1790 | AI->getFailureOrdering() != AtomicOrdering::Monotonic); | ||||||||
| 1791 | } | ||||||||
| 1792 | |||||||||
| 1793 | AtomicOrdering Ordering; | ||||||||
| 1794 | switch (I->getOpcode()) { | ||||||||
| 1795 | case Instruction::AtomicRMW: | ||||||||
| 1796 | Ordering = cast<AtomicRMWInst>(I)->getOrdering(); | ||||||||
| 1797 | break; | ||||||||
| 1798 | case Instruction::Store: | ||||||||
| 1799 | Ordering = cast<StoreInst>(I)->getOrdering(); | ||||||||
| 1800 | break; | ||||||||
| 1801 | case Instruction::Load: | ||||||||
| 1802 | Ordering = cast<LoadInst>(I)->getOrdering(); | ||||||||
| 1803 | break; | ||||||||
| 1804 | default: | ||||||||
| 1805 | llvm_unreachable(__builtin_unreachable() | ||||||||
| 1806 | "New atomic operations need to be known in the attributor.")__builtin_unreachable(); | ||||||||
| 1807 | } | ||||||||
| 1808 | |||||||||
| 1809 | return (Ordering != AtomicOrdering::Unordered && | ||||||||
| 1810 | Ordering != AtomicOrdering::Monotonic); | ||||||||
| 1811 | } | ||||||||
| 1812 | |||||||||
| 1813 | /// Return true if this intrinsic is nosync. This is only used for intrinsics | ||||||||
| 1814 | /// which would be nosync except that they have a volatile flag. All other | ||||||||
| 1815 | /// intrinsics are simply annotated with the nosync attribute in Intrinsics.td. | ||||||||
| 1816 | bool AANoSyncImpl::isNoSyncIntrinsic(Instruction *I) { | ||||||||
| 1817 | if (auto *MI = dyn_cast<MemIntrinsic>(I)) | ||||||||
| 1818 | return !MI->isVolatile(); | ||||||||
| 1819 | return false; | ||||||||
| 1820 | } | ||||||||
| 1821 | |||||||||
| 1822 | ChangeStatus AANoSyncImpl::updateImpl(Attributor &A) { | ||||||||
| 1823 | |||||||||
| 1824 | auto CheckRWInstForNoSync = [&](Instruction &I) { | ||||||||
| 1825 | /// We are looking for volatile instructions or Non-Relaxed atomics. | ||||||||
| 1826 | |||||||||
| 1827 | if (const auto *CB = dyn_cast<CallBase>(&I)) { | ||||||||
| 1828 | if (CB->hasFnAttr(Attribute::NoSync)) | ||||||||
| 1829 | return true; | ||||||||
| 1830 | |||||||||
| 1831 | if (isNoSyncIntrinsic(&I)) | ||||||||
| 1832 | return true; | ||||||||
| 1833 | |||||||||
| 1834 | const auto &NoSyncAA = A.getAAFor<AANoSync>( | ||||||||
| 1835 | *this, IRPosition::callsite_function(*CB), DepClassTy::REQUIRED); | ||||||||
| 1836 | return NoSyncAA.isAssumedNoSync(); | ||||||||
| 1837 | } | ||||||||
| 1838 | |||||||||
| 1839 | if (!I.isVolatile() && !isNonRelaxedAtomic(&I)) | ||||||||
| 1840 | return true; | ||||||||
| 1841 | |||||||||
| 1842 | return false; | ||||||||
| 1843 | }; | ||||||||
| 1844 | |||||||||
| 1845 | auto CheckForNoSync = [&](Instruction &I) { | ||||||||
| 1846 | // At this point we handled all read/write effects and they are all | ||||||||
| 1847 | // nosync, so they can be skipped. | ||||||||
| 1848 | if (I.mayReadOrWriteMemory()) | ||||||||
| 1849 | return true; | ||||||||
| 1850 | |||||||||
| 1851 | // non-convergent and readnone imply nosync. | ||||||||
| 1852 | return !cast<CallBase>(I).isConvergent(); | ||||||||
| 1853 | }; | ||||||||
| 1854 | |||||||||
| 1855 | bool UsedAssumedInformation = false; | ||||||||
| 1856 | if (!A.checkForAllReadWriteInstructions(CheckRWInstForNoSync, *this, | ||||||||
| 1857 | UsedAssumedInformation) || | ||||||||
| 1858 | !A.checkForAllCallLikeInstructions(CheckForNoSync, *this, | ||||||||
| 1859 | UsedAssumedInformation)) | ||||||||
| 1860 | return indicatePessimisticFixpoint(); | ||||||||
| 1861 | |||||||||
| 1862 | return ChangeStatus::UNCHANGED; | ||||||||
| 1863 | } | ||||||||
| 1864 | |||||||||
| 1865 | struct AANoSyncFunction final : public AANoSyncImpl { | ||||||||
| 1866 | AANoSyncFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 1867 | : AANoSyncImpl(IRP, A) {} | ||||||||
| 1868 | |||||||||
| 1869 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1870 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(nosync){ static llvm::Statistic NumIRFunction_nosync = {"attributor" , "NumIRFunction_nosync", ("Number of " "functions" " marked '" "nosync" "'")};; ++(NumIRFunction_nosync); } } | ||||||||
| 1871 | }; | ||||||||
| 1872 | |||||||||
| 1873 | /// NoSync attribute deduction for a call sites. | ||||||||
| 1874 | struct AANoSyncCallSite final : AANoSyncImpl { | ||||||||
| 1875 | AANoSyncCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 1876 | : AANoSyncImpl(IRP, A) {} | ||||||||
| 1877 | |||||||||
| 1878 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1879 | void initialize(Attributor &A) override { | ||||||||
| 1880 | AANoSyncImpl::initialize(A); | ||||||||
| 1881 | Function *F = getAssociatedFunction(); | ||||||||
| 1882 | if (!F || F->isDeclaration()) | ||||||||
| 1883 | indicatePessimisticFixpoint(); | ||||||||
| 1884 | } | ||||||||
| 1885 | |||||||||
| 1886 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1887 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1888 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 1889 | // call site specific liveness information and then it makes | ||||||||
| 1890 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 1891 | // redirecting requests to the callee argument. | ||||||||
| 1892 | Function *F = getAssociatedFunction(); | ||||||||
| 1893 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 1894 | auto &FnAA = A.getAAFor<AANoSync>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 1895 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 1896 | } | ||||||||
| 1897 | |||||||||
| 1898 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1899 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(nosync){ static llvm::Statistic NumIRCS_nosync = {"attributor", "NumIRCS_nosync" , ("Number of " "call site" " marked '" "nosync" "'")};; ++(NumIRCS_nosync ); }; } | ||||||||
| 1900 | }; | ||||||||
| 1901 | |||||||||
| 1902 | /// ------------------------ No-Free Attributes ---------------------------- | ||||||||
| 1903 | |||||||||
| 1904 | struct AANoFreeImpl : public AANoFree { | ||||||||
| 1905 | AANoFreeImpl(const IRPosition &IRP, Attributor &A) : AANoFree(IRP, A) {} | ||||||||
| 1906 | |||||||||
| 1907 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1908 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1909 | auto CheckForNoFree = [&](Instruction &I) { | ||||||||
| 1910 | const auto &CB = cast<CallBase>(I); | ||||||||
| 1911 | if (CB.hasFnAttr(Attribute::NoFree)) | ||||||||
| 1912 | return true; | ||||||||
| 1913 | |||||||||
| 1914 | const auto &NoFreeAA = A.getAAFor<AANoFree>( | ||||||||
| 1915 | *this, IRPosition::callsite_function(CB), DepClassTy::REQUIRED); | ||||||||
| 1916 | return NoFreeAA.isAssumedNoFree(); | ||||||||
| 1917 | }; | ||||||||
| 1918 | |||||||||
| 1919 | bool UsedAssumedInformation = false; | ||||||||
| 1920 | if (!A.checkForAllCallLikeInstructions(CheckForNoFree, *this, | ||||||||
| 1921 | UsedAssumedInformation)) | ||||||||
| 1922 | return indicatePessimisticFixpoint(); | ||||||||
| 1923 | return ChangeStatus::UNCHANGED; | ||||||||
| 1924 | } | ||||||||
| 1925 | |||||||||
| 1926 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 1927 | const std::string getAsStr() const override { | ||||||||
| 1928 | return getAssumed() ? "nofree" : "may-free"; | ||||||||
| 1929 | } | ||||||||
| 1930 | }; | ||||||||
| 1931 | |||||||||
| 1932 | struct AANoFreeFunction final : public AANoFreeImpl { | ||||||||
| 1933 | AANoFreeFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 1934 | : AANoFreeImpl(IRP, A) {} | ||||||||
| 1935 | |||||||||
| 1936 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1937 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(nofree){ static llvm::Statistic NumIRFunction_nofree = {"attributor" , "NumIRFunction_nofree", ("Number of " "functions" " marked '" "nofree" "'")};; ++(NumIRFunction_nofree); } } | ||||||||
| 1938 | }; | ||||||||
| 1939 | |||||||||
| 1940 | /// NoFree attribute deduction for a call sites. | ||||||||
| 1941 | struct AANoFreeCallSite final : AANoFreeImpl { | ||||||||
| 1942 | AANoFreeCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 1943 | : AANoFreeImpl(IRP, A) {} | ||||||||
| 1944 | |||||||||
| 1945 | /// See AbstractAttribute::initialize(...). | ||||||||
| 1946 | void initialize(Attributor &A) override { | ||||||||
| 1947 | AANoFreeImpl::initialize(A); | ||||||||
| 1948 | Function *F = getAssociatedFunction(); | ||||||||
| 1949 | if (!F || F->isDeclaration()) | ||||||||
| 1950 | indicatePessimisticFixpoint(); | ||||||||
| 1951 | } | ||||||||
| 1952 | |||||||||
| 1953 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 1954 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1955 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 1956 | // call site specific liveness information and then it makes | ||||||||
| 1957 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 1958 | // redirecting requests to the callee argument. | ||||||||
| 1959 | Function *F = getAssociatedFunction(); | ||||||||
| 1960 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 1961 | auto &FnAA = A.getAAFor<AANoFree>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 1962 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 1963 | } | ||||||||
| 1964 | |||||||||
| 1965 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1966 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(nofree){ static llvm::Statistic NumIRCS_nofree = {"attributor", "NumIRCS_nofree" , ("Number of " "call site" " marked '" "nofree" "'")};; ++(NumIRCS_nofree ); }; } | ||||||||
| 1967 | }; | ||||||||
| 1968 | |||||||||
| 1969 | /// NoFree attribute for floating values. | ||||||||
| 1970 | struct AANoFreeFloating : AANoFreeImpl { | ||||||||
| 1971 | AANoFreeFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 1972 | : AANoFreeImpl(IRP, A) {} | ||||||||
| 1973 | |||||||||
| 1974 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 1975 | void trackStatistics() const override{STATS_DECLTRACK_FLOATING_ATTR(nofree){ static llvm::Statistic NumIRFloating_nofree = {"attributor" , "NumIRFloating_nofree", ("Number of floating values known to be '" "nofree" "'")};; ++(NumIRFloating_nofree); }} | ||||||||
| 1976 | |||||||||
| 1977 | /// See Abstract Attribute::updateImpl(...). | ||||||||
| 1978 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 1979 | const IRPosition &IRP = getIRPosition(); | ||||||||
| 1980 | |||||||||
| 1981 | const auto &NoFreeAA = A.getAAFor<AANoFree>( | ||||||||
| 1982 | *this, IRPosition::function_scope(IRP), DepClassTy::OPTIONAL); | ||||||||
| 1983 | if (NoFreeAA.isAssumedNoFree()) | ||||||||
| 1984 | return ChangeStatus::UNCHANGED; | ||||||||
| 1985 | |||||||||
| 1986 | Value &AssociatedValue = getIRPosition().getAssociatedValue(); | ||||||||
| 1987 | auto Pred = [&](const Use &U, bool &Follow) -> bool { | ||||||||
| 1988 | Instruction *UserI = cast<Instruction>(U.getUser()); | ||||||||
| 1989 | if (auto *CB = dyn_cast<CallBase>(UserI)) { | ||||||||
| 1990 | if (CB->isBundleOperand(&U)) | ||||||||
| 1991 | return false; | ||||||||
| 1992 | if (!CB->isArgOperand(&U)) | ||||||||
| 1993 | return true; | ||||||||
| 1994 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||||||
| 1995 | |||||||||
| 1996 | const auto &NoFreeArg = A.getAAFor<AANoFree>( | ||||||||
| 1997 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||||||
| 1998 | DepClassTy::REQUIRED); | ||||||||
| 1999 | return NoFreeArg.isAssumedNoFree(); | ||||||||
| 2000 | } | ||||||||
| 2001 | |||||||||
| 2002 | if (isa<GetElementPtrInst>(UserI) || isa<BitCastInst>(UserI) || | ||||||||
| 2003 | isa<PHINode>(UserI) || isa<SelectInst>(UserI)) { | ||||||||
| 2004 | Follow = true; | ||||||||
| 2005 | return true; | ||||||||
| 2006 | } | ||||||||
| 2007 | if (isa<StoreInst>(UserI) || isa<LoadInst>(UserI) || | ||||||||
| 2008 | isa<ReturnInst>(UserI)) | ||||||||
| 2009 | return true; | ||||||||
| 2010 | |||||||||
| 2011 | // Unknown user. | ||||||||
| 2012 | return false; | ||||||||
| 2013 | }; | ||||||||
| 2014 | if (!A.checkForAllUses(Pred, *this, AssociatedValue)) | ||||||||
| 2015 | return indicatePessimisticFixpoint(); | ||||||||
| 2016 | |||||||||
| 2017 | return ChangeStatus::UNCHANGED; | ||||||||
| 2018 | } | ||||||||
| 2019 | }; | ||||||||
| 2020 | |||||||||
| 2021 | /// NoFree attribute for a call site argument. | ||||||||
| 2022 | struct AANoFreeArgument final : AANoFreeFloating { | ||||||||
| 2023 | AANoFreeArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 2024 | : AANoFreeFloating(IRP, A) {} | ||||||||
| 2025 | |||||||||
| 2026 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2027 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(nofree){ static llvm::Statistic NumIRArguments_nofree = {"attributor" , "NumIRArguments_nofree", ("Number of " "arguments" " marked '" "nofree" "'")};; ++(NumIRArguments_nofree); } } | ||||||||
| 2028 | }; | ||||||||
| 2029 | |||||||||
| 2030 | /// NoFree attribute for call site arguments. | ||||||||
| 2031 | struct AANoFreeCallSiteArgument final : AANoFreeFloating { | ||||||||
| 2032 | AANoFreeCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 2033 | : AANoFreeFloating(IRP, A) {} | ||||||||
| 2034 | |||||||||
| 2035 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2036 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2037 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 2038 | // call site specific liveness information and then it makes | ||||||||
| 2039 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 2040 | // redirecting requests to the callee argument. | ||||||||
| 2041 | Argument *Arg = getAssociatedArgument(); | ||||||||
| 2042 | if (!Arg) | ||||||||
| 2043 | return indicatePessimisticFixpoint(); | ||||||||
| 2044 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||||||
| 2045 | auto &ArgAA = A.getAAFor<AANoFree>(*this, ArgPos, DepClassTy::REQUIRED); | ||||||||
| 2046 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||||||
| 2047 | } | ||||||||
| 2048 | |||||||||
| 2049 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2050 | void trackStatistics() const override{STATS_DECLTRACK_CSARG_ATTR(nofree){ static llvm::Statistic NumIRCSArguments_nofree = {"attributor" , "NumIRCSArguments_nofree", ("Number of " "call site arguments" " marked '" "nofree" "'")};; ++(NumIRCSArguments_nofree); }}; | ||||||||
| 2051 | }; | ||||||||
| 2052 | |||||||||
| 2053 | /// NoFree attribute for function return value. | ||||||||
| 2054 | struct AANoFreeReturned final : AANoFreeFloating { | ||||||||
| 2055 | AANoFreeReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 2056 | : AANoFreeFloating(IRP, A) { | ||||||||
| 2057 | llvm_unreachable("NoFree is not applicable to function returns!")__builtin_unreachable(); | ||||||||
| 2058 | } | ||||||||
| 2059 | |||||||||
| 2060 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2061 | void initialize(Attributor &A) override { | ||||||||
| 2062 | llvm_unreachable("NoFree is not applicable to function returns!")__builtin_unreachable(); | ||||||||
| 2063 | } | ||||||||
| 2064 | |||||||||
| 2065 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2066 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2067 | llvm_unreachable("NoFree is not applicable to function returns!")__builtin_unreachable(); | ||||||||
| 2068 | } | ||||||||
| 2069 | |||||||||
| 2070 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2071 | void trackStatistics() const override {} | ||||||||
| 2072 | }; | ||||||||
| 2073 | |||||||||
| 2074 | /// NoFree attribute deduction for a call site return value. | ||||||||
| 2075 | struct AANoFreeCallSiteReturned final : AANoFreeFloating { | ||||||||
| 2076 | AANoFreeCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 2077 | : AANoFreeFloating(IRP, A) {} | ||||||||
| 2078 | |||||||||
| 2079 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 2080 | return ChangeStatus::UNCHANGED; | ||||||||
| 2081 | } | ||||||||
| 2082 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2083 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(nofree){ static llvm::Statistic NumIRCSReturn_nofree = {"attributor" , "NumIRCSReturn_nofree", ("Number of " "call site returns" " marked '" "nofree" "'")};; ++(NumIRCSReturn_nofree); } } | ||||||||
| 2084 | }; | ||||||||
| 2085 | |||||||||
| 2086 | /// ------------------------ NonNull Argument Attribute ------------------------ | ||||||||
| 2087 | static int64_t getKnownNonNullAndDerefBytesForUse( | ||||||||
| 2088 | Attributor &A, const AbstractAttribute &QueryingAA, Value &AssociatedValue, | ||||||||
| 2089 | const Use *U, const Instruction *I, bool &IsNonNull, bool &TrackUse) { | ||||||||
| 2090 | TrackUse = false; | ||||||||
| 2091 | |||||||||
| 2092 | const Value *UseV = U->get(); | ||||||||
| 2093 | if (!UseV->getType()->isPointerTy()) | ||||||||
| 2094 | return 0; | ||||||||
| 2095 | |||||||||
| 2096 | // We need to follow common pointer manipulation uses to the accesses they | ||||||||
| 2097 | // feed into. We can try to be smart to avoid looking through things we do not | ||||||||
| 2098 | // like for now, e.g., non-inbounds GEPs. | ||||||||
| 2099 | if (isa<CastInst>(I)) { | ||||||||
| 2100 | TrackUse = true; | ||||||||
| 2101 | return 0; | ||||||||
| 2102 | } | ||||||||
| 2103 | |||||||||
| 2104 | if (isa<GetElementPtrInst>(I)) { | ||||||||
| 2105 | TrackUse = true; | ||||||||
| 2106 | return 0; | ||||||||
| 2107 | } | ||||||||
| 2108 | |||||||||
| 2109 | Type *PtrTy = UseV->getType(); | ||||||||
| 2110 | const Function *F = I->getFunction(); | ||||||||
| 2111 | bool NullPointerIsDefined = | ||||||||
| 2112 | F ? llvm::NullPointerIsDefined(F, PtrTy->getPointerAddressSpace()) : true; | ||||||||
| 2113 | const DataLayout &DL = A.getInfoCache().getDL(); | ||||||||
| 2114 | if (const auto *CB = dyn_cast<CallBase>(I)) { | ||||||||
| 2115 | if (CB->isBundleOperand(U)) { | ||||||||
| 2116 | if (RetainedKnowledge RK = getKnowledgeFromUse( | ||||||||
| 2117 | U, {Attribute::NonNull, Attribute::Dereferenceable})) { | ||||||||
| 2118 | IsNonNull |= | ||||||||
| 2119 | (RK.AttrKind == Attribute::NonNull || !NullPointerIsDefined); | ||||||||
| 2120 | return RK.ArgValue; | ||||||||
| 2121 | } | ||||||||
| 2122 | return 0; | ||||||||
| 2123 | } | ||||||||
| 2124 | |||||||||
| 2125 | if (CB->isCallee(U)) { | ||||||||
| 2126 | IsNonNull |= !NullPointerIsDefined; | ||||||||
| 2127 | return 0; | ||||||||
| 2128 | } | ||||||||
| 2129 | |||||||||
| 2130 | unsigned ArgNo = CB->getArgOperandNo(U); | ||||||||
| 2131 | IRPosition IRP = IRPosition::callsite_argument(*CB, ArgNo); | ||||||||
| 2132 | // As long as we only use known information there is no need to track | ||||||||
| 2133 | // dependences here. | ||||||||
| 2134 | auto &DerefAA = | ||||||||
| 2135 | A.getAAFor<AADereferenceable>(QueryingAA, IRP, DepClassTy::NONE); | ||||||||
| 2136 | IsNonNull |= DerefAA.isKnownNonNull(); | ||||||||
| 2137 | return DerefAA.getKnownDereferenceableBytes(); | ||||||||
| 2138 | } | ||||||||
| 2139 | |||||||||
| 2140 | int64_t Offset; | ||||||||
| 2141 | const Value *Base = | ||||||||
| 2142 | getMinimalBaseOfAccsesPointerOperand(A, QueryingAA, I, Offset, DL); | ||||||||
| 2143 | if (Base) { | ||||||||
| 2144 | if (Base == &AssociatedValue && | ||||||||
| 2145 | getPointerOperand(I, /* AllowVolatile */ false) == UseV) { | ||||||||
| 2146 | int64_t DerefBytes = | ||||||||
| 2147 | (int64_t)DL.getTypeStoreSize(PtrTy->getPointerElementType()) + Offset; | ||||||||
| 2148 | |||||||||
| 2149 | IsNonNull |= !NullPointerIsDefined; | ||||||||
| 2150 | return std::max(int64_t(0), DerefBytes); | ||||||||
| 2151 | } | ||||||||
| 2152 | } | ||||||||
| 2153 | |||||||||
| 2154 | /// Corner case when an offset is 0. | ||||||||
| 2155 | Base = getBasePointerOfAccessPointerOperand(I, Offset, DL, | ||||||||
| 2156 | /*AllowNonInbounds*/ true); | ||||||||
| 2157 | if (Base) { | ||||||||
| 2158 | if (Offset == 0 && Base == &AssociatedValue && | ||||||||
| 2159 | getPointerOperand(I, /* AllowVolatile */ false) == UseV) { | ||||||||
| 2160 | int64_t DerefBytes = | ||||||||
| 2161 | (int64_t)DL.getTypeStoreSize(PtrTy->getPointerElementType()); | ||||||||
| 2162 | IsNonNull |= !NullPointerIsDefined; | ||||||||
| 2163 | return std::max(int64_t(0), DerefBytes); | ||||||||
| 2164 | } | ||||||||
| 2165 | } | ||||||||
| 2166 | |||||||||
| 2167 | return 0; | ||||||||
| 2168 | } | ||||||||
| 2169 | |||||||||
| 2170 | struct AANonNullImpl : AANonNull { | ||||||||
| 2171 | AANonNullImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 2172 | : AANonNull(IRP, A), | ||||||||
| 2173 | NullIsDefined(NullPointerIsDefined( | ||||||||
| 2174 | getAnchorScope(), | ||||||||
| 2175 | getAssociatedValue().getType()->getPointerAddressSpace())) {} | ||||||||
| 2176 | |||||||||
| 2177 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2178 | void initialize(Attributor &A) override { | ||||||||
| 2179 | Value &V = getAssociatedValue(); | ||||||||
| 2180 | if (!NullIsDefined && | ||||||||
| 2181 | hasAttr({Attribute::NonNull, Attribute::Dereferenceable}, | ||||||||
| 2182 | /* IgnoreSubsumingPositions */ false, &A)) { | ||||||||
| 2183 | indicateOptimisticFixpoint(); | ||||||||
| 2184 | return; | ||||||||
| 2185 | } | ||||||||
| 2186 | |||||||||
| 2187 | if (isa<ConstantPointerNull>(V)) { | ||||||||
| 2188 | indicatePessimisticFixpoint(); | ||||||||
| 2189 | return; | ||||||||
| 2190 | } | ||||||||
| 2191 | |||||||||
| 2192 | AANonNull::initialize(A); | ||||||||
| 2193 | |||||||||
| 2194 | bool CanBeNull, CanBeFreed; | ||||||||
| 2195 | if (V.getPointerDereferenceableBytes(A.getDataLayout(), CanBeNull, | ||||||||
| 2196 | CanBeFreed)) { | ||||||||
| 2197 | if (!CanBeNull) { | ||||||||
| 2198 | indicateOptimisticFixpoint(); | ||||||||
| 2199 | return; | ||||||||
| 2200 | } | ||||||||
| 2201 | } | ||||||||
| 2202 | |||||||||
| 2203 | if (isa<GlobalValue>(&getAssociatedValue())) { | ||||||||
| 2204 | indicatePessimisticFixpoint(); | ||||||||
| 2205 | return; | ||||||||
| 2206 | } | ||||||||
| 2207 | |||||||||
| 2208 | if (Instruction *CtxI = getCtxI()) | ||||||||
| 2209 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||||||
| 2210 | } | ||||||||
| 2211 | |||||||||
| 2212 | /// See followUsesInMBEC | ||||||||
| 2213 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||||||
| 2214 | AANonNull::StateType &State) { | ||||||||
| 2215 | bool IsNonNull = false; | ||||||||
| 2216 | bool TrackUse = false; | ||||||||
| 2217 | getKnownNonNullAndDerefBytesForUse(A, *this, getAssociatedValue(), U, I, | ||||||||
| 2218 | IsNonNull, TrackUse); | ||||||||
| 2219 | State.setKnown(IsNonNull); | ||||||||
| 2220 | return TrackUse; | ||||||||
| 2221 | } | ||||||||
| 2222 | |||||||||
| 2223 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 2224 | const std::string getAsStr() const override { | ||||||||
| 2225 | return getAssumed() ? "nonnull" : "may-null"; | ||||||||
| 2226 | } | ||||||||
| 2227 | |||||||||
| 2228 | /// Flag to determine if the underlying value can be null and still allow | ||||||||
| 2229 | /// valid accesses. | ||||||||
| 2230 | const bool NullIsDefined; | ||||||||
| 2231 | }; | ||||||||
| 2232 | |||||||||
| 2233 | /// NonNull attribute for a floating value. | ||||||||
| 2234 | struct AANonNullFloating : public AANonNullImpl { | ||||||||
| 2235 | AANonNullFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 2236 | : AANonNullImpl(IRP, A) {} | ||||||||
| 2237 | |||||||||
| 2238 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2239 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2240 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 2241 | |||||||||
| 2242 | DominatorTree *DT = nullptr; | ||||||||
| 2243 | AssumptionCache *AC = nullptr; | ||||||||
| 2244 | InformationCache &InfoCache = A.getInfoCache(); | ||||||||
| 2245 | if (const Function *Fn = getAnchorScope()) { | ||||||||
| 2246 | DT = InfoCache.getAnalysisResultForFunction<DominatorTreeAnalysis>(*Fn); | ||||||||
| 2247 | AC = InfoCache.getAnalysisResultForFunction<AssumptionAnalysis>(*Fn); | ||||||||
| 2248 | } | ||||||||
| 2249 | |||||||||
| 2250 | auto VisitValueCB = [&](Value &V, const Instruction *CtxI, | ||||||||
| 2251 | AANonNull::StateType &T, bool Stripped) -> bool { | ||||||||
| 2252 | const auto &AA = A.getAAFor<AANonNull>(*this, IRPosition::value(V), | ||||||||
| 2253 | DepClassTy::REQUIRED); | ||||||||
| 2254 | if (!Stripped && this == &AA) { | ||||||||
| 2255 | if (!isKnownNonZero(&V, DL, 0, AC, CtxI, DT)) | ||||||||
| 2256 | T.indicatePessimisticFixpoint(); | ||||||||
| 2257 | } else { | ||||||||
| 2258 | // Use abstract attribute information. | ||||||||
| 2259 | const AANonNull::StateType &NS = AA.getState(); | ||||||||
| 2260 | T ^= NS; | ||||||||
| 2261 | } | ||||||||
| 2262 | return T.isValidState(); | ||||||||
| 2263 | }; | ||||||||
| 2264 | |||||||||
| 2265 | StateType T; | ||||||||
| 2266 | if (!genericValueTraversal<StateType>(A, getIRPosition(), *this, T, | ||||||||
| 2267 | VisitValueCB, getCtxI())) | ||||||||
| 2268 | return indicatePessimisticFixpoint(); | ||||||||
| 2269 | |||||||||
| 2270 | return clampStateAndIndicateChange(getState(), T); | ||||||||
| 2271 | } | ||||||||
| 2272 | |||||||||
| 2273 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2274 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(nonnull){ static llvm::Statistic NumIRFunctionReturn_nonnull = {"attributor" , "NumIRFunctionReturn_nonnull", ("Number of " "function returns" " marked '" "nonnull" "'")};; ++(NumIRFunctionReturn_nonnull ); } } | ||||||||
| 2275 | }; | ||||||||
| 2276 | |||||||||
| 2277 | /// NonNull attribute for function return value. | ||||||||
| 2278 | struct AANonNullReturned final | ||||||||
| 2279 | : AAReturnedFromReturnedValues<AANonNull, AANonNull> { | ||||||||
| 2280 | AANonNullReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 2281 | : AAReturnedFromReturnedValues<AANonNull, AANonNull>(IRP, A) {} | ||||||||
| 2282 | |||||||||
| 2283 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 2284 | const std::string getAsStr() const override { | ||||||||
| 2285 | return getAssumed() ? "nonnull" : "may-null"; | ||||||||
| 2286 | } | ||||||||
| 2287 | |||||||||
| 2288 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2289 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(nonnull){ static llvm::Statistic NumIRFunctionReturn_nonnull = {"attributor" , "NumIRFunctionReturn_nonnull", ("Number of " "function returns" " marked '" "nonnull" "'")};; ++(NumIRFunctionReturn_nonnull ); } } | ||||||||
| 2290 | }; | ||||||||
| 2291 | |||||||||
| 2292 | /// NonNull attribute for function argument. | ||||||||
| 2293 | struct AANonNullArgument final | ||||||||
| 2294 | : AAArgumentFromCallSiteArguments<AANonNull, AANonNullImpl> { | ||||||||
| 2295 | AANonNullArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 2296 | : AAArgumentFromCallSiteArguments<AANonNull, AANonNullImpl>(IRP, A) {} | ||||||||
| 2297 | |||||||||
| 2298 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2299 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(nonnull){ static llvm::Statistic NumIRArguments_nonnull = {"attributor" , "NumIRArguments_nonnull", ("Number of " "arguments" " marked '" "nonnull" "'")};; ++(NumIRArguments_nonnull); } } | ||||||||
| 2300 | }; | ||||||||
| 2301 | |||||||||
| 2302 | struct AANonNullCallSiteArgument final : AANonNullFloating { | ||||||||
| 2303 | AANonNullCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 2304 | : AANonNullFloating(IRP, A) {} | ||||||||
| 2305 | |||||||||
| 2306 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2307 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(nonnull){ static llvm::Statistic NumIRCSArguments_nonnull = {"attributor" , "NumIRCSArguments_nonnull", ("Number of " "call site arguments" " marked '" "nonnull" "'")};; ++(NumIRCSArguments_nonnull); } } | ||||||||
| 2308 | }; | ||||||||
| 2309 | |||||||||
| 2310 | /// NonNull attribute for a call site return position. | ||||||||
| 2311 | struct AANonNullCallSiteReturned final | ||||||||
| 2312 | : AACallSiteReturnedFromReturned<AANonNull, AANonNullImpl> { | ||||||||
| 2313 | AANonNullCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 2314 | : AACallSiteReturnedFromReturned<AANonNull, AANonNullImpl>(IRP, A) {} | ||||||||
| 2315 | |||||||||
| 2316 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2317 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(nonnull){ static llvm::Statistic NumIRCSReturn_nonnull = {"attributor" , "NumIRCSReturn_nonnull", ("Number of " "call site returns" " marked '" "nonnull" "'")};; ++(NumIRCSReturn_nonnull); } } | ||||||||
| 2318 | }; | ||||||||
| 2319 | |||||||||
| 2320 | /// ------------------------ No-Recurse Attributes ---------------------------- | ||||||||
| 2321 | |||||||||
| 2322 | struct AANoRecurseImpl : public AANoRecurse { | ||||||||
| 2323 | AANoRecurseImpl(const IRPosition &IRP, Attributor &A) : AANoRecurse(IRP, A) {} | ||||||||
| 2324 | |||||||||
| 2325 | /// See AbstractAttribute::getAsStr() | ||||||||
| 2326 | const std::string getAsStr() const override { | ||||||||
| 2327 | return getAssumed() ? "norecurse" : "may-recurse"; | ||||||||
| 2328 | } | ||||||||
| 2329 | }; | ||||||||
| 2330 | |||||||||
| 2331 | struct AANoRecurseFunction final : AANoRecurseImpl { | ||||||||
| 2332 | AANoRecurseFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 2333 | : AANoRecurseImpl(IRP, A) {} | ||||||||
| 2334 | |||||||||
| 2335 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2336 | void initialize(Attributor &A) override { | ||||||||
| 2337 | AANoRecurseImpl::initialize(A); | ||||||||
| 2338 | if (const Function *F = getAnchorScope()) | ||||||||
| 2339 | if (A.getInfoCache().getSccSize(*F) != 1) | ||||||||
| 2340 | indicatePessimisticFixpoint(); | ||||||||
| 2341 | } | ||||||||
| 2342 | |||||||||
| 2343 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2344 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2345 | |||||||||
| 2346 | // If all live call sites are known to be no-recurse, we are as well. | ||||||||
| 2347 | auto CallSitePred = [&](AbstractCallSite ACS) { | ||||||||
| 2348 | const auto &NoRecurseAA = A.getAAFor<AANoRecurse>( | ||||||||
| 2349 | *this, IRPosition::function(*ACS.getInstruction()->getFunction()), | ||||||||
| 2350 | DepClassTy::NONE); | ||||||||
| 2351 | return NoRecurseAA.isKnownNoRecurse(); | ||||||||
| 2352 | }; | ||||||||
| 2353 | bool AllCallSitesKnown; | ||||||||
| 2354 | if (A.checkForAllCallSites(CallSitePred, *this, true, AllCallSitesKnown)) { | ||||||||
| 2355 | // If we know all call sites and all are known no-recurse, we are done. | ||||||||
| 2356 | // If all known call sites, which might not be all that exist, are known | ||||||||
| 2357 | // to be no-recurse, we are not done but we can continue to assume | ||||||||
| 2358 | // no-recurse. If one of the call sites we have not visited will become | ||||||||
| 2359 | // live, another update is triggered. | ||||||||
| 2360 | if (AllCallSitesKnown) | ||||||||
| 2361 | indicateOptimisticFixpoint(); | ||||||||
| 2362 | return ChangeStatus::UNCHANGED; | ||||||||
| 2363 | } | ||||||||
| 2364 | |||||||||
| 2365 | // If the above check does not hold anymore we look at the calls. | ||||||||
| 2366 | auto CheckForNoRecurse = [&](Instruction &I) { | ||||||||
| 2367 | const auto &CB = cast<CallBase>(I); | ||||||||
| 2368 | if (CB.hasFnAttr(Attribute::NoRecurse)) | ||||||||
| 2369 | return true; | ||||||||
| 2370 | |||||||||
| 2371 | const auto &NoRecurseAA = A.getAAFor<AANoRecurse>( | ||||||||
| 2372 | *this, IRPosition::callsite_function(CB), DepClassTy::REQUIRED); | ||||||||
| 2373 | if (!NoRecurseAA.isAssumedNoRecurse()) | ||||||||
| 2374 | return false; | ||||||||
| 2375 | |||||||||
| 2376 | // Recursion to the same function | ||||||||
| 2377 | if (CB.getCalledFunction() == getAnchorScope()) | ||||||||
| 2378 | return false; | ||||||||
| 2379 | |||||||||
| 2380 | return true; | ||||||||
| 2381 | }; | ||||||||
| 2382 | |||||||||
| 2383 | bool UsedAssumedInformation = false; | ||||||||
| 2384 | if (!A.checkForAllCallLikeInstructions(CheckForNoRecurse, *this, | ||||||||
| 2385 | UsedAssumedInformation)) | ||||||||
| 2386 | return indicatePessimisticFixpoint(); | ||||||||
| 2387 | return ChangeStatus::UNCHANGED; | ||||||||
| 2388 | } | ||||||||
| 2389 | |||||||||
| 2390 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(norecurse){ static llvm::Statistic NumIRFunction_norecurse = {"attributor" , "NumIRFunction_norecurse", ("Number of " "functions" " marked '" "norecurse" "'")};; ++(NumIRFunction_norecurse); } } | ||||||||
| 2391 | }; | ||||||||
| 2392 | |||||||||
| 2393 | /// NoRecurse attribute deduction for a call sites. | ||||||||
| 2394 | struct AANoRecurseCallSite final : AANoRecurseImpl { | ||||||||
| 2395 | AANoRecurseCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 2396 | : AANoRecurseImpl(IRP, A) {} | ||||||||
| 2397 | |||||||||
| 2398 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2399 | void initialize(Attributor &A) override { | ||||||||
| 2400 | AANoRecurseImpl::initialize(A); | ||||||||
| 2401 | Function *F = getAssociatedFunction(); | ||||||||
| 2402 | if (!F || F->isDeclaration()) | ||||||||
| 2403 | indicatePessimisticFixpoint(); | ||||||||
| 2404 | } | ||||||||
| 2405 | |||||||||
| 2406 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2407 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2408 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 2409 | // call site specific liveness information and then it makes | ||||||||
| 2410 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 2411 | // redirecting requests to the callee argument. | ||||||||
| 2412 | Function *F = getAssociatedFunction(); | ||||||||
| 2413 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 2414 | auto &FnAA = A.getAAFor<AANoRecurse>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 2415 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 2416 | } | ||||||||
| 2417 | |||||||||
| 2418 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2419 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(norecurse){ static llvm::Statistic NumIRCS_norecurse = {"attributor", "NumIRCS_norecurse" , ("Number of " "call site" " marked '" "norecurse" "'")};; ++ (NumIRCS_norecurse); }; } | ||||||||
| 2420 | }; | ||||||||
| 2421 | |||||||||
| 2422 | /// -------------------- Undefined-Behavior Attributes ------------------------ | ||||||||
| 2423 | |||||||||
| 2424 | struct AAUndefinedBehaviorImpl : public AAUndefinedBehavior { | ||||||||
| 2425 | AAUndefinedBehaviorImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 2426 | : AAUndefinedBehavior(IRP, A) {} | ||||||||
| 2427 | |||||||||
| 2428 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2429 | // through a pointer (i.e. also branches etc.) | ||||||||
| 2430 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2431 | const size_t UBPrevSize = KnownUBInsts.size(); | ||||||||
| 2432 | const size_t NoUBPrevSize = AssumedNoUBInsts.size(); | ||||||||
| 2433 | |||||||||
| 2434 | auto InspectMemAccessInstForUB = [&](Instruction &I) { | ||||||||
| 2435 | // Skip instructions that are already saved. | ||||||||
| 2436 | if (AssumedNoUBInsts.count(&I) || KnownUBInsts.count(&I)) | ||||||||
| 2437 | return true; | ||||||||
| 2438 | |||||||||
| 2439 | // If we reach here, we know we have an instruction | ||||||||
| 2440 | // that accesses memory through a pointer operand, | ||||||||
| 2441 | // for which getPointerOperand() should give it to us. | ||||||||
| 2442 | Value *PtrOp = | ||||||||
| 2443 | const_cast<Value *>(getPointerOperand(&I, /* AllowVolatile */ true)); | ||||||||
| 2444 | assert(PtrOp &&((void)0) | ||||||||
| 2445 | "Expected pointer operand of memory accessing instruction")((void)0); | ||||||||
| 2446 | |||||||||
| 2447 | // Either we stopped and the appropriate action was taken, | ||||||||
| 2448 | // or we got back a simplified value to continue. | ||||||||
| 2449 | Optional<Value *> SimplifiedPtrOp = stopOnUndefOrAssumed(A, PtrOp, &I); | ||||||||
| 2450 | if (!SimplifiedPtrOp.hasValue() || !SimplifiedPtrOp.getValue()) | ||||||||
| 2451 | return true; | ||||||||
| 2452 | const Value *PtrOpVal = SimplifiedPtrOp.getValue(); | ||||||||
| 2453 | |||||||||
| 2454 | // A memory access through a pointer is considered UB | ||||||||
| 2455 | // only if the pointer has constant null value. | ||||||||
| 2456 | // TODO: Expand it to not only check constant values. | ||||||||
| 2457 | if (!isa<ConstantPointerNull>(PtrOpVal)) { | ||||||||
| 2458 | AssumedNoUBInsts.insert(&I); | ||||||||
| 2459 | return true; | ||||||||
| 2460 | } | ||||||||
| 2461 | const Type *PtrTy = PtrOpVal->getType(); | ||||||||
| 2462 | |||||||||
| 2463 | // Because we only consider instructions inside functions, | ||||||||
| 2464 | // assume that a parent function exists. | ||||||||
| 2465 | const Function *F = I.getFunction(); | ||||||||
| 2466 | |||||||||
| 2467 | // A memory access using constant null pointer is only considered UB | ||||||||
| 2468 | // if null pointer is _not_ defined for the target platform. | ||||||||
| 2469 | if (llvm::NullPointerIsDefined(F, PtrTy->getPointerAddressSpace())) | ||||||||
| 2470 | AssumedNoUBInsts.insert(&I); | ||||||||
| 2471 | else | ||||||||
| 2472 | KnownUBInsts.insert(&I); | ||||||||
| 2473 | return true; | ||||||||
| 2474 | }; | ||||||||
| 2475 | |||||||||
| 2476 | auto InspectBrInstForUB = [&](Instruction &I) { | ||||||||
| 2477 | // A conditional branch instruction is considered UB if it has `undef` | ||||||||
| 2478 | // condition. | ||||||||
| 2479 | |||||||||
| 2480 | // Skip instructions that are already saved. | ||||||||
| 2481 | if (AssumedNoUBInsts.count(&I) || KnownUBInsts.count(&I)) | ||||||||
| 2482 | return true; | ||||||||
| 2483 | |||||||||
| 2484 | // We know we have a branch instruction. | ||||||||
| 2485 | auto *BrInst = cast<BranchInst>(&I); | ||||||||
| 2486 | |||||||||
| 2487 | // Unconditional branches are never considered UB. | ||||||||
| 2488 | if (BrInst->isUnconditional()) | ||||||||
| 2489 | return true; | ||||||||
| 2490 | |||||||||
| 2491 | // Either we stopped and the appropriate action was taken, | ||||||||
| 2492 | // or we got back a simplified value to continue. | ||||||||
| 2493 | Optional<Value *> SimplifiedCond = | ||||||||
| 2494 | stopOnUndefOrAssumed(A, BrInst->getCondition(), BrInst); | ||||||||
| 2495 | if (!SimplifiedCond.hasValue() || !SimplifiedCond.getValue()) | ||||||||
| 2496 | return true; | ||||||||
| 2497 | AssumedNoUBInsts.insert(&I); | ||||||||
| 2498 | return true; | ||||||||
| 2499 | }; | ||||||||
| 2500 | |||||||||
| 2501 | auto InspectCallSiteForUB = [&](Instruction &I) { | ||||||||
| 2502 | // Check whether a callsite always cause UB or not | ||||||||
| 2503 | |||||||||
| 2504 | // Skip instructions that are already saved. | ||||||||
| 2505 | if (AssumedNoUBInsts.count(&I) || KnownUBInsts.count(&I)) | ||||||||
| 2506 | return true; | ||||||||
| 2507 | |||||||||
| 2508 | // Check nonnull and noundef argument attribute violation for each | ||||||||
| 2509 | // callsite. | ||||||||
| 2510 | CallBase &CB = cast<CallBase>(I); | ||||||||
| 2511 | Function *Callee = CB.getCalledFunction(); | ||||||||
| 2512 | if (!Callee) | ||||||||
| 2513 | return true; | ||||||||
| 2514 | for (unsigned idx = 0; idx < CB.getNumArgOperands(); idx++) { | ||||||||
| 2515 | // If current argument is known to be simplified to null pointer and the | ||||||||
| 2516 | // corresponding argument position is known to have nonnull attribute, | ||||||||
| 2517 | // the argument is poison. Furthermore, if the argument is poison and | ||||||||
| 2518 | // the position is known to have noundef attriubte, this callsite is | ||||||||
| 2519 | // considered UB. | ||||||||
| 2520 | if (idx >= Callee->arg_size()) | ||||||||
| 2521 | break; | ||||||||
| 2522 | Value *ArgVal = CB.getArgOperand(idx); | ||||||||
| 2523 | if (!ArgVal) | ||||||||
| 2524 | continue; | ||||||||
| 2525 | // Here, we handle three cases. | ||||||||
| 2526 | // (1) Not having a value means it is dead. (we can replace the value | ||||||||
| 2527 | // with undef) | ||||||||
| 2528 | // (2) Simplified to undef. The argument violate noundef attriubte. | ||||||||
| 2529 | // (3) Simplified to null pointer where known to be nonnull. | ||||||||
| 2530 | // The argument is a poison value and violate noundef attribute. | ||||||||
| 2531 | IRPosition CalleeArgumentIRP = IRPosition::callsite_argument(CB, idx); | ||||||||
| 2532 | auto &NoUndefAA = | ||||||||
| 2533 | A.getAAFor<AANoUndef>(*this, CalleeArgumentIRP, DepClassTy::NONE); | ||||||||
| 2534 | if (!NoUndefAA.isKnownNoUndef()) | ||||||||
| 2535 | continue; | ||||||||
| 2536 | bool UsedAssumedInformation = false; | ||||||||
| 2537 | Optional<Value *> SimplifiedVal = A.getAssumedSimplified( | ||||||||
| 2538 | IRPosition::value(*ArgVal), *this, UsedAssumedInformation); | ||||||||
| 2539 | if (UsedAssumedInformation) | ||||||||
| 2540 | continue; | ||||||||
| 2541 | if (SimplifiedVal.hasValue() && !SimplifiedVal.getValue()) | ||||||||
| 2542 | return true; | ||||||||
| 2543 | if (!SimplifiedVal.hasValue() || | ||||||||
| 2544 | isa<UndefValue>(*SimplifiedVal.getValue())) { | ||||||||
| 2545 | KnownUBInsts.insert(&I); | ||||||||
| 2546 | continue; | ||||||||
| 2547 | } | ||||||||
| 2548 | if (!ArgVal->getType()->isPointerTy() || | ||||||||
| 2549 | !isa<ConstantPointerNull>(*SimplifiedVal.getValue())) | ||||||||
| 2550 | continue; | ||||||||
| 2551 | auto &NonNullAA = | ||||||||
| 2552 | A.getAAFor<AANonNull>(*this, CalleeArgumentIRP, DepClassTy::NONE); | ||||||||
| 2553 | if (NonNullAA.isKnownNonNull()) | ||||||||
| 2554 | KnownUBInsts.insert(&I); | ||||||||
| 2555 | } | ||||||||
| 2556 | return true; | ||||||||
| 2557 | }; | ||||||||
| 2558 | |||||||||
| 2559 | auto InspectReturnInstForUB = | ||||||||
| 2560 | [&](Value &V, const SmallSetVector<ReturnInst *, 4> RetInsts) { | ||||||||
| 2561 | // Check if a return instruction always cause UB or not | ||||||||
| 2562 | // Note: It is guaranteed that the returned position of the anchor | ||||||||
| 2563 | // scope has noundef attribute when this is called. | ||||||||
| 2564 | // We also ensure the return position is not "assumed dead" | ||||||||
| 2565 | // because the returned value was then potentially simplified to | ||||||||
| 2566 | // `undef` in AAReturnedValues without removing the `noundef` | ||||||||
| 2567 | // attribute yet. | ||||||||
| 2568 | |||||||||
| 2569 | // When the returned position has noundef attriubte, UB occur in the | ||||||||
| 2570 | // following cases. | ||||||||
| 2571 | // (1) Returned value is known to be undef. | ||||||||
| 2572 | // (2) The value is known to be a null pointer and the returned | ||||||||
| 2573 | // position has nonnull attribute (because the returned value is | ||||||||
| 2574 | // poison). | ||||||||
| 2575 | bool FoundUB = false; | ||||||||
| 2576 | if (isa<UndefValue>(V)) { | ||||||||
| 2577 | FoundUB = true; | ||||||||
| 2578 | } else { | ||||||||
| 2579 | if (isa<ConstantPointerNull>(V)) { | ||||||||
| 2580 | auto &NonNullAA = A.getAAFor<AANonNull>( | ||||||||
| 2581 | *this, IRPosition::returned(*getAnchorScope()), | ||||||||
| 2582 | DepClassTy::NONE); | ||||||||
| 2583 | if (NonNullAA.isKnownNonNull()) | ||||||||
| 2584 | FoundUB = true; | ||||||||
| 2585 | } | ||||||||
| 2586 | } | ||||||||
| 2587 | |||||||||
| 2588 | if (FoundUB) | ||||||||
| 2589 | for (ReturnInst *RI : RetInsts) | ||||||||
| 2590 | KnownUBInsts.insert(RI); | ||||||||
| 2591 | return true; | ||||||||
| 2592 | }; | ||||||||
| 2593 | |||||||||
| 2594 | bool UsedAssumedInformation = false; | ||||||||
| 2595 | A.checkForAllInstructions(InspectMemAccessInstForUB, *this, | ||||||||
| 2596 | {Instruction::Load, Instruction::Store, | ||||||||
| 2597 | Instruction::AtomicCmpXchg, | ||||||||
| 2598 | Instruction::AtomicRMW}, | ||||||||
| 2599 | UsedAssumedInformation, | ||||||||
| 2600 | /* CheckBBLivenessOnly */ true); | ||||||||
| 2601 | A.checkForAllInstructions(InspectBrInstForUB, *this, {Instruction::Br}, | ||||||||
| 2602 | UsedAssumedInformation, | ||||||||
| 2603 | /* CheckBBLivenessOnly */ true); | ||||||||
| 2604 | A.checkForAllCallLikeInstructions(InspectCallSiteForUB, *this, | ||||||||
| 2605 | UsedAssumedInformation); | ||||||||
| 2606 | |||||||||
| 2607 | // If the returned position of the anchor scope has noundef attriubte, check | ||||||||
| 2608 | // all returned instructions. | ||||||||
| 2609 | if (!getAnchorScope()->getReturnType()->isVoidTy()) { | ||||||||
| 2610 | const IRPosition &ReturnIRP = IRPosition::returned(*getAnchorScope()); | ||||||||
| 2611 | if (!A.isAssumedDead(ReturnIRP, this, nullptr, UsedAssumedInformation)) { | ||||||||
| 2612 | auto &RetPosNoUndefAA = | ||||||||
| 2613 | A.getAAFor<AANoUndef>(*this, ReturnIRP, DepClassTy::NONE); | ||||||||
| 2614 | if (RetPosNoUndefAA.isKnownNoUndef()) | ||||||||
| 2615 | A.checkForAllReturnedValuesAndReturnInsts(InspectReturnInstForUB, | ||||||||
| 2616 | *this); | ||||||||
| 2617 | } | ||||||||
| 2618 | } | ||||||||
| 2619 | |||||||||
| 2620 | if (NoUBPrevSize != AssumedNoUBInsts.size() || | ||||||||
| 2621 | UBPrevSize != KnownUBInsts.size()) | ||||||||
| 2622 | return ChangeStatus::CHANGED; | ||||||||
| 2623 | return ChangeStatus::UNCHANGED; | ||||||||
| 2624 | } | ||||||||
| 2625 | |||||||||
| 2626 | bool isKnownToCauseUB(Instruction *I) const override { | ||||||||
| 2627 | return KnownUBInsts.count(I); | ||||||||
| 2628 | } | ||||||||
| 2629 | |||||||||
| 2630 | bool isAssumedToCauseUB(Instruction *I) const override { | ||||||||
| 2631 | // In simple words, if an instruction is not in the assumed to _not_ | ||||||||
| 2632 | // cause UB, then it is assumed UB (that includes those | ||||||||
| 2633 | // in the KnownUBInsts set). The rest is boilerplate | ||||||||
| 2634 | // is to ensure that it is one of the instructions we test | ||||||||
| 2635 | // for UB. | ||||||||
| 2636 | |||||||||
| 2637 | switch (I->getOpcode()) { | ||||||||
| 2638 | case Instruction::Load: | ||||||||
| 2639 | case Instruction::Store: | ||||||||
| 2640 | case Instruction::AtomicCmpXchg: | ||||||||
| 2641 | case Instruction::AtomicRMW: | ||||||||
| 2642 | return !AssumedNoUBInsts.count(I); | ||||||||
| 2643 | case Instruction::Br: { | ||||||||
| 2644 | auto BrInst = cast<BranchInst>(I); | ||||||||
| 2645 | if (BrInst->isUnconditional()) | ||||||||
| 2646 | return false; | ||||||||
| 2647 | return !AssumedNoUBInsts.count(I); | ||||||||
| 2648 | } break; | ||||||||
| 2649 | default: | ||||||||
| 2650 | return false; | ||||||||
| 2651 | } | ||||||||
| 2652 | return false; | ||||||||
| 2653 | } | ||||||||
| 2654 | |||||||||
| 2655 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 2656 | if (KnownUBInsts.empty()) | ||||||||
| 2657 | return ChangeStatus::UNCHANGED; | ||||||||
| 2658 | for (Instruction *I : KnownUBInsts) | ||||||||
| 2659 | A.changeToUnreachableAfterManifest(I); | ||||||||
| 2660 | return ChangeStatus::CHANGED; | ||||||||
| 2661 | } | ||||||||
| 2662 | |||||||||
| 2663 | /// See AbstractAttribute::getAsStr() | ||||||||
| 2664 | const std::string getAsStr() const override { | ||||||||
| 2665 | return getAssumed() ? "undefined-behavior" : "no-ub"; | ||||||||
| 2666 | } | ||||||||
| 2667 | |||||||||
| 2668 | /// Note: The correctness of this analysis depends on the fact that the | ||||||||
| 2669 | /// following 2 sets will stop changing after some point. | ||||||||
| 2670 | /// "Change" here means that their size changes. | ||||||||
| 2671 | /// The size of each set is monotonically increasing | ||||||||
| 2672 | /// (we only add items to them) and it is upper bounded by the number of | ||||||||
| 2673 | /// instructions in the processed function (we can never save more | ||||||||
| 2674 | /// elements in either set than this number). Hence, at some point, | ||||||||
| 2675 | /// they will stop increasing. | ||||||||
| 2676 | /// Consequently, at some point, both sets will have stopped | ||||||||
| 2677 | /// changing, effectively making the analysis reach a fixpoint. | ||||||||
| 2678 | |||||||||
| 2679 | /// Note: These 2 sets are disjoint and an instruction can be considered | ||||||||
| 2680 | /// one of 3 things: | ||||||||
| 2681 | /// 1) Known to cause UB (AAUndefinedBehavior could prove it) and put it in | ||||||||
| 2682 | /// the KnownUBInsts set. | ||||||||
| 2683 | /// 2) Assumed to cause UB (in every updateImpl, AAUndefinedBehavior | ||||||||
| 2684 | /// has a reason to assume it). | ||||||||
| 2685 | /// 3) Assumed to not cause UB. very other instruction - AAUndefinedBehavior | ||||||||
| 2686 | /// could not find a reason to assume or prove that it can cause UB, | ||||||||
| 2687 | /// hence it assumes it doesn't. We have a set for these instructions | ||||||||
| 2688 | /// so that we don't reprocess them in every update. | ||||||||
| 2689 | /// Note however that instructions in this set may cause UB. | ||||||||
| 2690 | |||||||||
| 2691 | protected: | ||||||||
| 2692 | /// A set of all live instructions _known_ to cause UB. | ||||||||
| 2693 | SmallPtrSet<Instruction *, 8> KnownUBInsts; | ||||||||
| 2694 | |||||||||
| 2695 | private: | ||||||||
| 2696 | /// A set of all the (live) instructions that are assumed to _not_ cause UB. | ||||||||
| 2697 | SmallPtrSet<Instruction *, 8> AssumedNoUBInsts; | ||||||||
| 2698 | |||||||||
| 2699 | // Should be called on updates in which if we're processing an instruction | ||||||||
| 2700 | // \p I that depends on a value \p V, one of the following has to happen: | ||||||||
| 2701 | // - If the value is assumed, then stop. | ||||||||
| 2702 | // - If the value is known but undef, then consider it UB. | ||||||||
| 2703 | // - Otherwise, do specific processing with the simplified value. | ||||||||
| 2704 | // We return None in the first 2 cases to signify that an appropriate | ||||||||
| 2705 | // action was taken and the caller should stop. | ||||||||
| 2706 | // Otherwise, we return the simplified value that the caller should | ||||||||
| 2707 | // use for specific processing. | ||||||||
| 2708 | Optional<Value *> stopOnUndefOrAssumed(Attributor &A, Value *V, | ||||||||
| 2709 | Instruction *I) { | ||||||||
| 2710 | bool UsedAssumedInformation = false; | ||||||||
| 2711 | Optional<Value *> SimplifiedV = A.getAssumedSimplified( | ||||||||
| 2712 | IRPosition::value(*V), *this, UsedAssumedInformation); | ||||||||
| 2713 | if (!UsedAssumedInformation) { | ||||||||
| 2714 | // Don't depend on assumed values. | ||||||||
| 2715 | if (!SimplifiedV.hasValue()) { | ||||||||
| 2716 | // If it is known (which we tested above) but it doesn't have a value, | ||||||||
| 2717 | // then we can assume `undef` and hence the instruction is UB. | ||||||||
| 2718 | KnownUBInsts.insert(I); | ||||||||
| 2719 | return llvm::None; | ||||||||
| 2720 | } | ||||||||
| 2721 | if (!SimplifiedV.getValue()) | ||||||||
| 2722 | return nullptr; | ||||||||
| 2723 | V = *SimplifiedV; | ||||||||
| 2724 | } | ||||||||
| 2725 | if (isa<UndefValue>(V)) { | ||||||||
| 2726 | KnownUBInsts.insert(I); | ||||||||
| 2727 | return llvm::None; | ||||||||
| 2728 | } | ||||||||
| 2729 | return V; | ||||||||
| 2730 | } | ||||||||
| 2731 | }; | ||||||||
| 2732 | |||||||||
| 2733 | struct AAUndefinedBehaviorFunction final : AAUndefinedBehaviorImpl { | ||||||||
| 2734 | AAUndefinedBehaviorFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 2735 | : AAUndefinedBehaviorImpl(IRP, A) {} | ||||||||
| 2736 | |||||||||
| 2737 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2738 | void trackStatistics() const override { | ||||||||
| 2739 | STATS_DECL(UndefinedBehaviorInstruction, Instruction,static llvm::Statistic NumIRInstruction_UndefinedBehaviorInstruction = {"attributor", "NumIRInstruction_UndefinedBehaviorInstruction" , "Number of instructions known to have UB"};; | ||||||||
| 2740 | "Number of instructions known to have UB")static llvm::Statistic NumIRInstruction_UndefinedBehaviorInstruction = {"attributor", "NumIRInstruction_UndefinedBehaviorInstruction" , "Number of instructions known to have UB"};;; | ||||||||
| 2741 | BUILD_STAT_NAME(UndefinedBehaviorInstruction, Instruction)NumIRInstruction_UndefinedBehaviorInstruction += | ||||||||
| 2742 | KnownUBInsts.size(); | ||||||||
| 2743 | } | ||||||||
| 2744 | }; | ||||||||
| 2745 | |||||||||
| 2746 | /// ------------------------ Will-Return Attributes ---------------------------- | ||||||||
| 2747 | |||||||||
| 2748 | // Helper function that checks whether a function has any cycle which we don't | ||||||||
| 2749 | // know if it is bounded or not. | ||||||||
| 2750 | // Loops with maximum trip count are considered bounded, any other cycle not. | ||||||||
| 2751 | static bool mayContainUnboundedCycle(Function &F, Attributor &A) { | ||||||||
| 2752 | ScalarEvolution *SE = | ||||||||
| 2753 | A.getInfoCache().getAnalysisResultForFunction<ScalarEvolutionAnalysis>(F); | ||||||||
| 2754 | LoopInfo *LI = A.getInfoCache().getAnalysisResultForFunction<LoopAnalysis>(F); | ||||||||
| 2755 | // If either SCEV or LoopInfo is not available for the function then we assume | ||||||||
| 2756 | // any cycle to be unbounded cycle. | ||||||||
| 2757 | // We use scc_iterator which uses Tarjan algorithm to find all the maximal | ||||||||
| 2758 | // SCCs.To detect if there's a cycle, we only need to find the maximal ones. | ||||||||
| 2759 | if (!SE || !LI) { | ||||||||
| 2760 | for (scc_iterator<Function *> SCCI = scc_begin(&F); !SCCI.isAtEnd(); ++SCCI) | ||||||||
| 2761 | if (SCCI.hasCycle()) | ||||||||
| 2762 | return true; | ||||||||
| 2763 | return false; | ||||||||
| 2764 | } | ||||||||
| 2765 | |||||||||
| 2766 | // If there's irreducible control, the function may contain non-loop cycles. | ||||||||
| 2767 | if (mayContainIrreducibleControl(F, LI)) | ||||||||
| 2768 | return true; | ||||||||
| 2769 | |||||||||
| 2770 | // Any loop that does not have a max trip count is considered unbounded cycle. | ||||||||
| 2771 | for (auto *L : LI->getLoopsInPreorder()) { | ||||||||
| 2772 | if (!SE->getSmallConstantMaxTripCount(L)) | ||||||||
| 2773 | return true; | ||||||||
| 2774 | } | ||||||||
| 2775 | return false; | ||||||||
| 2776 | } | ||||||||
| 2777 | |||||||||
| 2778 | struct AAWillReturnImpl : public AAWillReturn { | ||||||||
| 2779 | AAWillReturnImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 2780 | : AAWillReturn(IRP, A) {} | ||||||||
| 2781 | |||||||||
| 2782 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2783 | void initialize(Attributor &A) override { | ||||||||
| 2784 | AAWillReturn::initialize(A); | ||||||||
| 2785 | |||||||||
| 2786 | if (isImpliedByMustprogressAndReadonly(A, /* KnownOnly */ true)) { | ||||||||
| 2787 | indicateOptimisticFixpoint(); | ||||||||
| 2788 | return; | ||||||||
| 2789 | } | ||||||||
| 2790 | } | ||||||||
| 2791 | |||||||||
| 2792 | /// Check for `mustprogress` and `readonly` as they imply `willreturn`. | ||||||||
| 2793 | bool isImpliedByMustprogressAndReadonly(Attributor &A, bool KnownOnly) { | ||||||||
| 2794 | // Check for `mustprogress` in the scope and the associated function which | ||||||||
| 2795 | // might be different if this is a call site. | ||||||||
| 2796 | if ((!getAnchorScope() || !getAnchorScope()->mustProgress()) && | ||||||||
| 2797 | (!getAssociatedFunction() || !getAssociatedFunction()->mustProgress())) | ||||||||
| 2798 | return false; | ||||||||
| 2799 | |||||||||
| 2800 | const auto &MemAA = | ||||||||
| 2801 | A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), DepClassTy::NONE); | ||||||||
| 2802 | if (!MemAA.isAssumedReadOnly()) | ||||||||
| 2803 | return false; | ||||||||
| 2804 | if (KnownOnly && !MemAA.isKnownReadOnly()) | ||||||||
| 2805 | return false; | ||||||||
| 2806 | if (!MemAA.isKnownReadOnly()) | ||||||||
| 2807 | A.recordDependence(MemAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 2808 | |||||||||
| 2809 | return true; | ||||||||
| 2810 | } | ||||||||
| 2811 | |||||||||
| 2812 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2813 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2814 | if (isImpliedByMustprogressAndReadonly(A, /* KnownOnly */ false)) | ||||||||
| 2815 | return ChangeStatus::UNCHANGED; | ||||||||
| 2816 | |||||||||
| 2817 | auto CheckForWillReturn = [&](Instruction &I) { | ||||||||
| 2818 | IRPosition IPos = IRPosition::callsite_function(cast<CallBase>(I)); | ||||||||
| 2819 | const auto &WillReturnAA = | ||||||||
| 2820 | A.getAAFor<AAWillReturn>(*this, IPos, DepClassTy::REQUIRED); | ||||||||
| 2821 | if (WillReturnAA.isKnownWillReturn()) | ||||||||
| 2822 | return true; | ||||||||
| 2823 | if (!WillReturnAA.isAssumedWillReturn()) | ||||||||
| 2824 | return false; | ||||||||
| 2825 | const auto &NoRecurseAA = | ||||||||
| 2826 | A.getAAFor<AANoRecurse>(*this, IPos, DepClassTy::REQUIRED); | ||||||||
| 2827 | return NoRecurseAA.isAssumedNoRecurse(); | ||||||||
| 2828 | }; | ||||||||
| 2829 | |||||||||
| 2830 | bool UsedAssumedInformation = false; | ||||||||
| 2831 | if (!A.checkForAllCallLikeInstructions(CheckForWillReturn, *this, | ||||||||
| 2832 | UsedAssumedInformation)) | ||||||||
| 2833 | return indicatePessimisticFixpoint(); | ||||||||
| 2834 | |||||||||
| 2835 | return ChangeStatus::UNCHANGED; | ||||||||
| 2836 | } | ||||||||
| 2837 | |||||||||
| 2838 | /// See AbstractAttribute::getAsStr() | ||||||||
| 2839 | const std::string getAsStr() const override { | ||||||||
| 2840 | return getAssumed() ? "willreturn" : "may-noreturn"; | ||||||||
| 2841 | } | ||||||||
| 2842 | }; | ||||||||
| 2843 | |||||||||
| 2844 | struct AAWillReturnFunction final : AAWillReturnImpl { | ||||||||
| 2845 | AAWillReturnFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 2846 | : AAWillReturnImpl(IRP, A) {} | ||||||||
| 2847 | |||||||||
| 2848 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2849 | void initialize(Attributor &A) override { | ||||||||
| 2850 | AAWillReturnImpl::initialize(A); | ||||||||
| 2851 | |||||||||
| 2852 | Function *F = getAnchorScope(); | ||||||||
| 2853 | if (!F || F->isDeclaration() || mayContainUnboundedCycle(*F, A)) | ||||||||
| 2854 | indicatePessimisticFixpoint(); | ||||||||
| 2855 | } | ||||||||
| 2856 | |||||||||
| 2857 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2858 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(willreturn){ static llvm::Statistic NumIRFunction_willreturn = {"attributor" , "NumIRFunction_willreturn", ("Number of " "functions" " marked '" "willreturn" "'")};; ++(NumIRFunction_willreturn); } } | ||||||||
| 2859 | }; | ||||||||
| 2860 | |||||||||
| 2861 | /// WillReturn attribute deduction for a call sites. | ||||||||
| 2862 | struct AAWillReturnCallSite final : AAWillReturnImpl { | ||||||||
| 2863 | AAWillReturnCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 2864 | : AAWillReturnImpl(IRP, A) {} | ||||||||
| 2865 | |||||||||
| 2866 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2867 | void initialize(Attributor &A) override { | ||||||||
| 2868 | AAWillReturnImpl::initialize(A); | ||||||||
| 2869 | Function *F = getAssociatedFunction(); | ||||||||
| 2870 | if (!F || !A.isFunctionIPOAmendable(*F)) | ||||||||
| 2871 | indicatePessimisticFixpoint(); | ||||||||
| 2872 | } | ||||||||
| 2873 | |||||||||
| 2874 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2875 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2876 | if (isImpliedByMustprogressAndReadonly(A, /* KnownOnly */ false)) | ||||||||
| 2877 | return ChangeStatus::UNCHANGED; | ||||||||
| 2878 | |||||||||
| 2879 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 2880 | // call site specific liveness information and then it makes | ||||||||
| 2881 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 2882 | // redirecting requests to the callee argument. | ||||||||
| 2883 | Function *F = getAssociatedFunction(); | ||||||||
| 2884 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 2885 | auto &FnAA = A.getAAFor<AAWillReturn>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 2886 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 2887 | } | ||||||||
| 2888 | |||||||||
| 2889 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2890 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(willreturn){ static llvm::Statistic NumIRCS_willreturn = {"attributor", "NumIRCS_willreturn" , ("Number of " "call site" " marked '" "willreturn" "'")};; ++ (NumIRCS_willreturn); }; } | ||||||||
| 2891 | }; | ||||||||
| 2892 | |||||||||
| 2893 | /// -------------------AAReachability Attribute-------------------------- | ||||||||
| 2894 | |||||||||
| 2895 | struct AAReachabilityImpl : AAReachability { | ||||||||
| 2896 | AAReachabilityImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 2897 | : AAReachability(IRP, A) {} | ||||||||
| 2898 | |||||||||
| 2899 | const std::string getAsStr() const override { | ||||||||
| 2900 | // TODO: Return the number of reachable queries. | ||||||||
| 2901 | return "reachable"; | ||||||||
| 2902 | } | ||||||||
| 2903 | |||||||||
| 2904 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2905 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2906 | return ChangeStatus::UNCHANGED; | ||||||||
| 2907 | } | ||||||||
| 2908 | }; | ||||||||
| 2909 | |||||||||
| 2910 | struct AAReachabilityFunction final : public AAReachabilityImpl { | ||||||||
| 2911 | AAReachabilityFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 2912 | : AAReachabilityImpl(IRP, A) {} | ||||||||
| 2913 | |||||||||
| 2914 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2915 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(reachable){ static llvm::Statistic NumIRFunction_reachable = {"attributor" , "NumIRFunction_reachable", ("Number of " "functions" " marked '" "reachable" "'")};; ++(NumIRFunction_reachable); }; } | ||||||||
| 2916 | }; | ||||||||
| 2917 | |||||||||
| 2918 | /// ------------------------ NoAlias Argument Attribute ------------------------ | ||||||||
| 2919 | |||||||||
| 2920 | struct AANoAliasImpl : AANoAlias { | ||||||||
| 2921 | AANoAliasImpl(const IRPosition &IRP, Attributor &A) : AANoAlias(IRP, A) { | ||||||||
| 2922 | assert(getAssociatedType()->isPointerTy() &&((void)0) | ||||||||
| 2923 | "Noalias is a pointer attribute")((void)0); | ||||||||
| 2924 | } | ||||||||
| 2925 | |||||||||
| 2926 | const std::string getAsStr() const override { | ||||||||
| 2927 | return getAssumed() ? "noalias" : "may-alias"; | ||||||||
| 2928 | } | ||||||||
| 2929 | }; | ||||||||
| 2930 | |||||||||
| 2931 | /// NoAlias attribute for a floating value. | ||||||||
| 2932 | struct AANoAliasFloating final : AANoAliasImpl { | ||||||||
| 2933 | AANoAliasFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 2934 | : AANoAliasImpl(IRP, A) {} | ||||||||
| 2935 | |||||||||
| 2936 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2937 | void initialize(Attributor &A) override { | ||||||||
| 2938 | AANoAliasImpl::initialize(A); | ||||||||
| 2939 | Value *Val = &getAssociatedValue(); | ||||||||
| 2940 | do { | ||||||||
| 2941 | CastInst *CI = dyn_cast<CastInst>(Val); | ||||||||
| 2942 | if (!CI) | ||||||||
| 2943 | break; | ||||||||
| 2944 | Value *Base = CI->getOperand(0); | ||||||||
| 2945 | if (!Base->hasOneUse()) | ||||||||
| 2946 | break; | ||||||||
| 2947 | Val = Base; | ||||||||
| 2948 | } while (true); | ||||||||
| 2949 | |||||||||
| 2950 | if (!Val->getType()->isPointerTy()) { | ||||||||
| 2951 | indicatePessimisticFixpoint(); | ||||||||
| 2952 | return; | ||||||||
| 2953 | } | ||||||||
| 2954 | |||||||||
| 2955 | if (isa<AllocaInst>(Val)) | ||||||||
| 2956 | indicateOptimisticFixpoint(); | ||||||||
| 2957 | else if (isa<ConstantPointerNull>(Val) && | ||||||||
| 2958 | !NullPointerIsDefined(getAnchorScope(), | ||||||||
| 2959 | Val->getType()->getPointerAddressSpace())) | ||||||||
| 2960 | indicateOptimisticFixpoint(); | ||||||||
| 2961 | else if (Val != &getAssociatedValue()) { | ||||||||
| 2962 | const auto &ValNoAliasAA = A.getAAFor<AANoAlias>( | ||||||||
| 2963 | *this, IRPosition::value(*Val), DepClassTy::OPTIONAL); | ||||||||
| 2964 | if (ValNoAliasAA.isKnownNoAlias()) | ||||||||
| 2965 | indicateOptimisticFixpoint(); | ||||||||
| 2966 | } | ||||||||
| 2967 | } | ||||||||
| 2968 | |||||||||
| 2969 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 2970 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2971 | // TODO: Implement this. | ||||||||
| 2972 | return indicatePessimisticFixpoint(); | ||||||||
| 2973 | } | ||||||||
| 2974 | |||||||||
| 2975 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 2976 | void trackStatistics() const override { | ||||||||
| 2977 | STATS_DECLTRACK_FLOATING_ATTR(noalias){ static llvm::Statistic NumIRFloating_noalias = {"attributor" , "NumIRFloating_noalias", ("Number of floating values known to be '" "noalias" "'")};; ++(NumIRFloating_noalias); } | ||||||||
| 2978 | } | ||||||||
| 2979 | }; | ||||||||
| 2980 | |||||||||
| 2981 | /// NoAlias attribute for an argument. | ||||||||
| 2982 | struct AANoAliasArgument final | ||||||||
| 2983 | : AAArgumentFromCallSiteArguments<AANoAlias, AANoAliasImpl> { | ||||||||
| 2984 | using Base = AAArgumentFromCallSiteArguments<AANoAlias, AANoAliasImpl>; | ||||||||
| 2985 | AANoAliasArgument(const IRPosition &IRP, Attributor &A) : Base(IRP, A) {} | ||||||||
| 2986 | |||||||||
| 2987 | /// See AbstractAttribute::initialize(...). | ||||||||
| 2988 | void initialize(Attributor &A) override { | ||||||||
| 2989 | Base::initialize(A); | ||||||||
| 2990 | // See callsite argument attribute and callee argument attribute. | ||||||||
| 2991 | if (hasAttr({Attribute::ByVal})) | ||||||||
| 2992 | indicateOptimisticFixpoint(); | ||||||||
| 2993 | } | ||||||||
| 2994 | |||||||||
| 2995 | /// See AbstractAttribute::update(...). | ||||||||
| 2996 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 2997 | // We have to make sure no-alias on the argument does not break | ||||||||
| 2998 | // synchronization when this is a callback argument, see also [1] below. | ||||||||
| 2999 | // If synchronization cannot be affected, we delegate to the base updateImpl | ||||||||
| 3000 | // function, otherwise we give up for now. | ||||||||
| 3001 | |||||||||
| 3002 | // If the function is no-sync, no-alias cannot break synchronization. | ||||||||
| 3003 | const auto &NoSyncAA = | ||||||||
| 3004 | A.getAAFor<AANoSync>(*this, IRPosition::function_scope(getIRPosition()), | ||||||||
| 3005 | DepClassTy::OPTIONAL); | ||||||||
| 3006 | if (NoSyncAA.isAssumedNoSync()) | ||||||||
| 3007 | return Base::updateImpl(A); | ||||||||
| 3008 | |||||||||
| 3009 | // If the argument is read-only, no-alias cannot break synchronization. | ||||||||
| 3010 | const auto &MemBehaviorAA = A.getAAFor<AAMemoryBehavior>( | ||||||||
| 3011 | *this, getIRPosition(), DepClassTy::OPTIONAL); | ||||||||
| 3012 | if (MemBehaviorAA.isAssumedReadOnly()) | ||||||||
| 3013 | return Base::updateImpl(A); | ||||||||
| 3014 | |||||||||
| 3015 | // If the argument is never passed through callbacks, no-alias cannot break | ||||||||
| 3016 | // synchronization. | ||||||||
| 3017 | bool AllCallSitesKnown; | ||||||||
| 3018 | if (A.checkForAllCallSites( | ||||||||
| 3019 | [](AbstractCallSite ACS) { return !ACS.isCallbackCall(); }, *this, | ||||||||
| 3020 | true, AllCallSitesKnown)) | ||||||||
| 3021 | return Base::updateImpl(A); | ||||||||
| 3022 | |||||||||
| 3023 | // TODO: add no-alias but make sure it doesn't break synchronization by | ||||||||
| 3024 | // introducing fake uses. See: | ||||||||
| 3025 | // [1] Compiler Optimizations for OpenMP, J. Doerfert and H. Finkel, | ||||||||
| 3026 | // International Workshop on OpenMP 2018, | ||||||||
| 3027 | // http://compilers.cs.uni-saarland.de/people/doerfert/par_opt18.pdf | ||||||||
| 3028 | |||||||||
| 3029 | return indicatePessimisticFixpoint(); | ||||||||
| 3030 | } | ||||||||
| 3031 | |||||||||
| 3032 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3033 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(noalias){ static llvm::Statistic NumIRArguments_noalias = {"attributor" , "NumIRArguments_noalias", ("Number of " "arguments" " marked '" "noalias" "'")};; ++(NumIRArguments_noalias); } } | ||||||||
| 3034 | }; | ||||||||
| 3035 | |||||||||
| 3036 | struct AANoAliasCallSiteArgument final : AANoAliasImpl { | ||||||||
| 3037 | AANoAliasCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 3038 | : AANoAliasImpl(IRP, A) {} | ||||||||
| 3039 | |||||||||
| 3040 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3041 | void initialize(Attributor &A) override { | ||||||||
| 3042 | // See callsite argument attribute and callee argument attribute. | ||||||||
| 3043 | const auto &CB = cast<CallBase>(getAnchorValue()); | ||||||||
| 3044 | if (CB.paramHasAttr(getCallSiteArgNo(), Attribute::NoAlias)) | ||||||||
| 3045 | indicateOptimisticFixpoint(); | ||||||||
| 3046 | Value &Val = getAssociatedValue(); | ||||||||
| 3047 | if (isa<ConstantPointerNull>(Val) && | ||||||||
| 3048 | !NullPointerIsDefined(getAnchorScope(), | ||||||||
| 3049 | Val.getType()->getPointerAddressSpace())) | ||||||||
| 3050 | indicateOptimisticFixpoint(); | ||||||||
| 3051 | } | ||||||||
| 3052 | |||||||||
| 3053 | /// Determine if the underlying value may alias with the call site argument | ||||||||
| 3054 | /// \p OtherArgNo of \p ICS (= the underlying call site). | ||||||||
| 3055 | bool mayAliasWithArgument(Attributor &A, AAResults *&AAR, | ||||||||
| 3056 | const AAMemoryBehavior &MemBehaviorAA, | ||||||||
| 3057 | const CallBase &CB, unsigned OtherArgNo) { | ||||||||
| 3058 | // We do not need to worry about aliasing with the underlying IRP. | ||||||||
| 3059 | if (this->getCalleeArgNo() == (int)OtherArgNo) | ||||||||
| 3060 | return false; | ||||||||
| 3061 | |||||||||
| 3062 | // If it is not a pointer or pointer vector we do not alias. | ||||||||
| 3063 | const Value *ArgOp = CB.getArgOperand(OtherArgNo); | ||||||||
| 3064 | if (!ArgOp->getType()->isPtrOrPtrVectorTy()) | ||||||||
| 3065 | return false; | ||||||||
| 3066 | |||||||||
| 3067 | auto &CBArgMemBehaviorAA = A.getAAFor<AAMemoryBehavior>( | ||||||||
| 3068 | *this, IRPosition::callsite_argument(CB, OtherArgNo), DepClassTy::NONE); | ||||||||
| 3069 | |||||||||
| 3070 | // If the argument is readnone, there is no read-write aliasing. | ||||||||
| 3071 | if (CBArgMemBehaviorAA.isAssumedReadNone()) { | ||||||||
| 3072 | A.recordDependence(CBArgMemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3073 | return false; | ||||||||
| 3074 | } | ||||||||
| 3075 | |||||||||
| 3076 | // If the argument is readonly and the underlying value is readonly, there | ||||||||
| 3077 | // is no read-write aliasing. | ||||||||
| 3078 | bool IsReadOnly = MemBehaviorAA.isAssumedReadOnly(); | ||||||||
| 3079 | if (CBArgMemBehaviorAA.isAssumedReadOnly() && IsReadOnly) { | ||||||||
| 3080 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3081 | A.recordDependence(CBArgMemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3082 | return false; | ||||||||
| 3083 | } | ||||||||
| 3084 | |||||||||
| 3085 | // We have to utilize actual alias analysis queries so we need the object. | ||||||||
| 3086 | if (!AAR) | ||||||||
| 3087 | AAR = A.getInfoCache().getAAResultsForFunction(*getAnchorScope()); | ||||||||
| 3088 | |||||||||
| 3089 | // Try to rule it out at the call site. | ||||||||
| 3090 | bool IsAliasing = !AAR || !AAR->isNoAlias(&getAssociatedValue(), ArgOp); | ||||||||
| 3091 | LLVM_DEBUG(dbgs() << "[NoAliasCSArg] Check alias between "do { } while (false) | ||||||||
| 3092 | "callsite arguments: "do { } while (false) | ||||||||
| 3093 | << getAssociatedValue() << " " << *ArgOp << " => "do { } while (false) | ||||||||
| 3094 | << (IsAliasing ? "" : "no-") << "alias \n")do { } while (false); | ||||||||
| 3095 | |||||||||
| 3096 | return IsAliasing; | ||||||||
| 3097 | } | ||||||||
| 3098 | |||||||||
| 3099 | bool | ||||||||
| 3100 | isKnownNoAliasDueToNoAliasPreservation(Attributor &A, AAResults *&AAR, | ||||||||
| 3101 | const AAMemoryBehavior &MemBehaviorAA, | ||||||||
| 3102 | const AANoAlias &NoAliasAA) { | ||||||||
| 3103 | // We can deduce "noalias" if the following conditions hold. | ||||||||
| 3104 | // (i) Associated value is assumed to be noalias in the definition. | ||||||||
| 3105 | // (ii) Associated value is assumed to be no-capture in all the uses | ||||||||
| 3106 | // possibly executed before this callsite. | ||||||||
| 3107 | // (iii) There is no other pointer argument which could alias with the | ||||||||
| 3108 | // value. | ||||||||
| 3109 | |||||||||
| 3110 | bool AssociatedValueIsNoAliasAtDef = NoAliasAA.isAssumedNoAlias(); | ||||||||
| 3111 | if (!AssociatedValueIsNoAliasAtDef) { | ||||||||
| 3112 | LLVM_DEBUG(dbgs() << "[AANoAlias] " << getAssociatedValue()do { } while (false) | ||||||||
| 3113 | << " is not no-alias at the definition\n")do { } while (false); | ||||||||
| 3114 | return false; | ||||||||
| 3115 | } | ||||||||
| 3116 | |||||||||
| 3117 | A.recordDependence(NoAliasAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3118 | |||||||||
| 3119 | const IRPosition &VIRP = IRPosition::value(getAssociatedValue()); | ||||||||
| 3120 | const Function *ScopeFn = VIRP.getAnchorScope(); | ||||||||
| 3121 | auto &NoCaptureAA = A.getAAFor<AANoCapture>(*this, VIRP, DepClassTy::NONE); | ||||||||
| 3122 | // Check whether the value is captured in the scope using AANoCapture. | ||||||||
| 3123 | // Look at CFG and check only uses possibly executed before this | ||||||||
| 3124 | // callsite. | ||||||||
| 3125 | auto UsePred = [&](const Use &U, bool &Follow) -> bool { | ||||||||
| 3126 | Instruction *UserI = cast<Instruction>(U.getUser()); | ||||||||
| 3127 | |||||||||
| 3128 | // If UserI is the curr instruction and there is a single potential use of | ||||||||
| 3129 | // the value in UserI we allow the use. | ||||||||
| 3130 | // TODO: We should inspect the operands and allow those that cannot alias | ||||||||
| 3131 | // with the value. | ||||||||
| 3132 | if (UserI == getCtxI() && UserI->getNumOperands() == 1) | ||||||||
| 3133 | return true; | ||||||||
| 3134 | |||||||||
| 3135 | if (ScopeFn) { | ||||||||
| 3136 | const auto &ReachabilityAA = A.getAAFor<AAReachability>( | ||||||||
| 3137 | *this, IRPosition::function(*ScopeFn), DepClassTy::OPTIONAL); | ||||||||
| 3138 | |||||||||
| 3139 | if (!ReachabilityAA.isAssumedReachable(A, *UserI, *getCtxI())) | ||||||||
| 3140 | return true; | ||||||||
| 3141 | |||||||||
| 3142 | if (auto *CB = dyn_cast<CallBase>(UserI)) { | ||||||||
| 3143 | if (CB->isArgOperand(&U)) { | ||||||||
| 3144 | |||||||||
| 3145 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||||||
| 3146 | |||||||||
| 3147 | const auto &NoCaptureAA = A.getAAFor<AANoCapture>( | ||||||||
| 3148 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||||||
| 3149 | DepClassTy::OPTIONAL); | ||||||||
| 3150 | |||||||||
| 3151 | if (NoCaptureAA.isAssumedNoCapture()) | ||||||||
| 3152 | return true; | ||||||||
| 3153 | } | ||||||||
| 3154 | } | ||||||||
| 3155 | } | ||||||||
| 3156 | |||||||||
| 3157 | // For cases which can potentially have more users | ||||||||
| 3158 | if (isa<GetElementPtrInst>(U) || isa<BitCastInst>(U) || isa<PHINode>(U) || | ||||||||
| 3159 | isa<SelectInst>(U)) { | ||||||||
| 3160 | Follow = true; | ||||||||
| 3161 | return true; | ||||||||
| 3162 | } | ||||||||
| 3163 | |||||||||
| 3164 | LLVM_DEBUG(dbgs() << "[AANoAliasCSArg] Unknown user: " << *U << "\n")do { } while (false); | ||||||||
| 3165 | return false; | ||||||||
| 3166 | }; | ||||||||
| 3167 | |||||||||
| 3168 | if (!NoCaptureAA.isAssumedNoCaptureMaybeReturned()) { | ||||||||
| 3169 | if (!A.checkForAllUses(UsePred, *this, getAssociatedValue())) { | ||||||||
| 3170 | LLVM_DEBUG(do { } while (false) | ||||||||
| 3171 | dbgs() << "[AANoAliasCSArg] " << getAssociatedValue()do { } while (false) | ||||||||
| 3172 | << " cannot be noalias as it is potentially captured\n")do { } while (false); | ||||||||
| 3173 | return false; | ||||||||
| 3174 | } | ||||||||
| 3175 | } | ||||||||
| 3176 | A.recordDependence(NoCaptureAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3177 | |||||||||
| 3178 | // Check there is no other pointer argument which could alias with the | ||||||||
| 3179 | // value passed at this call site. | ||||||||
| 3180 | // TODO: AbstractCallSite | ||||||||
| 3181 | const auto &CB = cast<CallBase>(getAnchorValue()); | ||||||||
| 3182 | for (unsigned OtherArgNo = 0; OtherArgNo < CB.getNumArgOperands(); | ||||||||
| 3183 | OtherArgNo++) | ||||||||
| 3184 | if (mayAliasWithArgument(A, AAR, MemBehaviorAA, CB, OtherArgNo)) | ||||||||
| 3185 | return false; | ||||||||
| 3186 | |||||||||
| 3187 | return true; | ||||||||
| 3188 | } | ||||||||
| 3189 | |||||||||
| 3190 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3191 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3192 | // If the argument is readnone we are done as there are no accesses via the | ||||||||
| 3193 | // argument. | ||||||||
| 3194 | auto &MemBehaviorAA = | ||||||||
| 3195 | A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), DepClassTy::NONE); | ||||||||
| 3196 | if (MemBehaviorAA.isAssumedReadNone()) { | ||||||||
| 3197 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3198 | return ChangeStatus::UNCHANGED; | ||||||||
| 3199 | } | ||||||||
| 3200 | |||||||||
| 3201 | const IRPosition &VIRP = IRPosition::value(getAssociatedValue()); | ||||||||
| 3202 | const auto &NoAliasAA = | ||||||||
| 3203 | A.getAAFor<AANoAlias>(*this, VIRP, DepClassTy::NONE); | ||||||||
| 3204 | |||||||||
| 3205 | AAResults *AAR = nullptr; | ||||||||
| 3206 | if (isKnownNoAliasDueToNoAliasPreservation(A, AAR, MemBehaviorAA, | ||||||||
| 3207 | NoAliasAA)) { | ||||||||
| 3208 | LLVM_DEBUG(do { } while (false) | ||||||||
| 3209 | dbgs() << "[AANoAlias] No-Alias deduced via no-alias preservation\n")do { } while (false); | ||||||||
| 3210 | return ChangeStatus::UNCHANGED; | ||||||||
| 3211 | } | ||||||||
| 3212 | |||||||||
| 3213 | return indicatePessimisticFixpoint(); | ||||||||
| 3214 | } | ||||||||
| 3215 | |||||||||
| 3216 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3217 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(noalias){ static llvm::Statistic NumIRCSArguments_noalias = {"attributor" , "NumIRCSArguments_noalias", ("Number of " "call site arguments" " marked '" "noalias" "'")};; ++(NumIRCSArguments_noalias); } } | ||||||||
| 3218 | }; | ||||||||
| 3219 | |||||||||
| 3220 | /// NoAlias attribute for function return value. | ||||||||
| 3221 | struct AANoAliasReturned final : AANoAliasImpl { | ||||||||
| 3222 | AANoAliasReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 3223 | : AANoAliasImpl(IRP, A) {} | ||||||||
| 3224 | |||||||||
| 3225 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3226 | void initialize(Attributor &A) override { | ||||||||
| 3227 | AANoAliasImpl::initialize(A); | ||||||||
| 3228 | Function *F = getAssociatedFunction(); | ||||||||
| 3229 | if (!F || F->isDeclaration()) | ||||||||
| 3230 | indicatePessimisticFixpoint(); | ||||||||
| 3231 | } | ||||||||
| 3232 | |||||||||
| 3233 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3234 | virtual ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3235 | |||||||||
| 3236 | auto CheckReturnValue = [&](Value &RV) -> bool { | ||||||||
| 3237 | if (Constant *C = dyn_cast<Constant>(&RV)) | ||||||||
| 3238 | if (C->isNullValue() || isa<UndefValue>(C)) | ||||||||
| 3239 | return true; | ||||||||
| 3240 | |||||||||
| 3241 | /// For now, we can only deduce noalias if we have call sites. | ||||||||
| 3242 | /// FIXME: add more support. | ||||||||
| 3243 | if (!isa<CallBase>(&RV)) | ||||||||
| 3244 | return false; | ||||||||
| 3245 | |||||||||
| 3246 | const IRPosition &RVPos = IRPosition::value(RV); | ||||||||
| 3247 | const auto &NoAliasAA = | ||||||||
| 3248 | A.getAAFor<AANoAlias>(*this, RVPos, DepClassTy::REQUIRED); | ||||||||
| 3249 | if (!NoAliasAA.isAssumedNoAlias()) | ||||||||
| 3250 | return false; | ||||||||
| 3251 | |||||||||
| 3252 | const auto &NoCaptureAA = | ||||||||
| 3253 | A.getAAFor<AANoCapture>(*this, RVPos, DepClassTy::REQUIRED); | ||||||||
| 3254 | return NoCaptureAA.isAssumedNoCaptureMaybeReturned(); | ||||||||
| 3255 | }; | ||||||||
| 3256 | |||||||||
| 3257 | if (!A.checkForAllReturnedValues(CheckReturnValue, *this)) | ||||||||
| 3258 | return indicatePessimisticFixpoint(); | ||||||||
| 3259 | |||||||||
| 3260 | return ChangeStatus::UNCHANGED; | ||||||||
| 3261 | } | ||||||||
| 3262 | |||||||||
| 3263 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3264 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(noalias){ static llvm::Statistic NumIRFunctionReturn_noalias = {"attributor" , "NumIRFunctionReturn_noalias", ("Number of " "function returns" " marked '" "noalias" "'")};; ++(NumIRFunctionReturn_noalias ); } } | ||||||||
| 3265 | }; | ||||||||
| 3266 | |||||||||
| 3267 | /// NoAlias attribute deduction for a call site return value. | ||||||||
| 3268 | struct AANoAliasCallSiteReturned final : AANoAliasImpl { | ||||||||
| 3269 | AANoAliasCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 3270 | : AANoAliasImpl(IRP, A) {} | ||||||||
| 3271 | |||||||||
| 3272 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3273 | void initialize(Attributor &A) override { | ||||||||
| 3274 | AANoAliasImpl::initialize(A); | ||||||||
| 3275 | Function *F = getAssociatedFunction(); | ||||||||
| 3276 | if (!F || F->isDeclaration()) | ||||||||
| 3277 | indicatePessimisticFixpoint(); | ||||||||
| 3278 | } | ||||||||
| 3279 | |||||||||
| 3280 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3281 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3282 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 3283 | // call site specific liveness information and then it makes | ||||||||
| 3284 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 3285 | // redirecting requests to the callee argument. | ||||||||
| 3286 | Function *F = getAssociatedFunction(); | ||||||||
| 3287 | const IRPosition &FnPos = IRPosition::returned(*F); | ||||||||
| 3288 | auto &FnAA = A.getAAFor<AANoAlias>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 3289 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 3290 | } | ||||||||
| 3291 | |||||||||
| 3292 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3293 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(noalias){ static llvm::Statistic NumIRCSReturn_noalias = {"attributor" , "NumIRCSReturn_noalias", ("Number of " "call site returns" " marked '" "noalias" "'")};; ++(NumIRCSReturn_noalias); }; } | ||||||||
| 3294 | }; | ||||||||
| 3295 | |||||||||
| 3296 | /// -------------------AAIsDead Function Attribute----------------------- | ||||||||
| 3297 | |||||||||
| 3298 | struct AAIsDeadValueImpl : public AAIsDead { | ||||||||
| 3299 | AAIsDeadValueImpl(const IRPosition &IRP, Attributor &A) : AAIsDead(IRP, A) {} | ||||||||
| 3300 | |||||||||
| 3301 | /// See AAIsDead::isAssumedDead(). | ||||||||
| 3302 | bool isAssumedDead() const override { return isAssumed(IS_DEAD); } | ||||||||
| 3303 | |||||||||
| 3304 | /// See AAIsDead::isKnownDead(). | ||||||||
| 3305 | bool isKnownDead() const override { return isKnown(IS_DEAD); } | ||||||||
| 3306 | |||||||||
| 3307 | /// See AAIsDead::isAssumedDead(BasicBlock *). | ||||||||
| 3308 | bool isAssumedDead(const BasicBlock *BB) const override { return false; } | ||||||||
| 3309 | |||||||||
| 3310 | /// See AAIsDead::isKnownDead(BasicBlock *). | ||||||||
| 3311 | bool isKnownDead(const BasicBlock *BB) const override { return false; } | ||||||||
| 3312 | |||||||||
| 3313 | /// See AAIsDead::isAssumedDead(Instruction *I). | ||||||||
| 3314 | bool isAssumedDead(const Instruction *I) const override { | ||||||||
| 3315 | return I == getCtxI() && isAssumedDead(); | ||||||||
| 3316 | } | ||||||||
| 3317 | |||||||||
| 3318 | /// See AAIsDead::isKnownDead(Instruction *I). | ||||||||
| 3319 | bool isKnownDead(const Instruction *I) const override { | ||||||||
| 3320 | return isAssumedDead(I) && isKnownDead(); | ||||||||
| 3321 | } | ||||||||
| 3322 | |||||||||
| 3323 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 3324 | const std::string getAsStr() const override { | ||||||||
| 3325 | return isAssumedDead() ? "assumed-dead" : "assumed-live"; | ||||||||
| 3326 | } | ||||||||
| 3327 | |||||||||
| 3328 | /// Check if all uses are assumed dead. | ||||||||
| 3329 | bool areAllUsesAssumedDead(Attributor &A, Value &V) { | ||||||||
| 3330 | // Callers might not check the type, void has no uses. | ||||||||
| 3331 | if (V.getType()->isVoidTy()) | ||||||||
| 3332 | return true; | ||||||||
| 3333 | |||||||||
| 3334 | // If we replace a value with a constant there are no uses left afterwards. | ||||||||
| 3335 | if (!isa<Constant>(V)) { | ||||||||
| 3336 | bool UsedAssumedInformation = false; | ||||||||
| 3337 | Optional<Constant *> C = | ||||||||
| 3338 | A.getAssumedConstant(V, *this, UsedAssumedInformation); | ||||||||
| 3339 | if (!C.hasValue() || *C) | ||||||||
| 3340 | return true; | ||||||||
| 3341 | } | ||||||||
| 3342 | |||||||||
| 3343 | auto UsePred = [&](const Use &U, bool &Follow) { return false; }; | ||||||||
| 3344 | // Explicitly set the dependence class to required because we want a long | ||||||||
| 3345 | // chain of N dependent instructions to be considered live as soon as one is | ||||||||
| 3346 | // without going through N update cycles. This is not required for | ||||||||
| 3347 | // correctness. | ||||||||
| 3348 | return A.checkForAllUses(UsePred, *this, V, /* CheckBBLivenessOnly */ false, | ||||||||
| 3349 | DepClassTy::REQUIRED); | ||||||||
| 3350 | } | ||||||||
| 3351 | |||||||||
| 3352 | /// Determine if \p I is assumed to be side-effect free. | ||||||||
| 3353 | bool isAssumedSideEffectFree(Attributor &A, Instruction *I) { | ||||||||
| 3354 | if (!I || wouldInstructionBeTriviallyDead(I)) | ||||||||
| 3355 | return true; | ||||||||
| 3356 | |||||||||
| 3357 | auto *CB = dyn_cast<CallBase>(I); | ||||||||
| 3358 | if (!CB || isa<IntrinsicInst>(CB)) | ||||||||
| 3359 | return false; | ||||||||
| 3360 | |||||||||
| 3361 | const IRPosition &CallIRP = IRPosition::callsite_function(*CB); | ||||||||
| 3362 | const auto &NoUnwindAA = | ||||||||
| 3363 | A.getAndUpdateAAFor<AANoUnwind>(*this, CallIRP, DepClassTy::NONE); | ||||||||
| 3364 | if (!NoUnwindAA.isAssumedNoUnwind()) | ||||||||
| 3365 | return false; | ||||||||
| 3366 | if (!NoUnwindAA.isKnownNoUnwind()) | ||||||||
| 3367 | A.recordDependence(NoUnwindAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3368 | |||||||||
| 3369 | const auto &MemBehaviorAA = | ||||||||
| 3370 | A.getAndUpdateAAFor<AAMemoryBehavior>(*this, CallIRP, DepClassTy::NONE); | ||||||||
| 3371 | if (MemBehaviorAA.isAssumedReadOnly()) { | ||||||||
| 3372 | if (!MemBehaviorAA.isKnownReadOnly()) | ||||||||
| 3373 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 3374 | return true; | ||||||||
| 3375 | } | ||||||||
| 3376 | return false; | ||||||||
| 3377 | } | ||||||||
| 3378 | }; | ||||||||
| 3379 | |||||||||
| 3380 | struct AAIsDeadFloating : public AAIsDeadValueImpl { | ||||||||
| 3381 | AAIsDeadFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 3382 | : AAIsDeadValueImpl(IRP, A) {} | ||||||||
| 3383 | |||||||||
| 3384 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3385 | void initialize(Attributor &A) override { | ||||||||
| 3386 | if (isa<UndefValue>(getAssociatedValue())) { | ||||||||
| 3387 | indicatePessimisticFixpoint(); | ||||||||
| 3388 | return; | ||||||||
| 3389 | } | ||||||||
| 3390 | |||||||||
| 3391 | Instruction *I = dyn_cast<Instruction>(&getAssociatedValue()); | ||||||||
| 3392 | if (!isAssumedSideEffectFree(A, I)) { | ||||||||
| 3393 | if (!isa_and_nonnull<StoreInst>(I)) | ||||||||
| 3394 | indicatePessimisticFixpoint(); | ||||||||
| 3395 | else | ||||||||
| 3396 | removeAssumedBits(HAS_NO_EFFECT); | ||||||||
| 3397 | } | ||||||||
| 3398 | } | ||||||||
| 3399 | |||||||||
| 3400 | bool isDeadStore(Attributor &A, StoreInst &SI) { | ||||||||
| 3401 | bool UsedAssumedInformation = false; | ||||||||
| 3402 | SmallSetVector<Value *, 4> PotentialCopies; | ||||||||
| 3403 | if (!AA::getPotentialCopiesOfStoredValue(A, SI, PotentialCopies, *this, | ||||||||
| 3404 | UsedAssumedInformation)) | ||||||||
| 3405 | return false; | ||||||||
| 3406 | return llvm::all_of(PotentialCopies, [&](Value *V) { | ||||||||
| 3407 | return A.isAssumedDead(IRPosition::value(*V), this, nullptr, | ||||||||
| 3408 | UsedAssumedInformation); | ||||||||
| 3409 | }); | ||||||||
| 3410 | } | ||||||||
| 3411 | |||||||||
| 3412 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3413 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3414 | Instruction *I = dyn_cast<Instruction>(&getAssociatedValue()); | ||||||||
| 3415 | if (auto *SI = dyn_cast_or_null<StoreInst>(I)) { | ||||||||
| 3416 | if (!isDeadStore(A, *SI)) | ||||||||
| 3417 | return indicatePessimisticFixpoint(); | ||||||||
| 3418 | } else { | ||||||||
| 3419 | if (!isAssumedSideEffectFree(A, I)) | ||||||||
| 3420 | return indicatePessimisticFixpoint(); | ||||||||
| 3421 | if (!areAllUsesAssumedDead(A, getAssociatedValue())) | ||||||||
| 3422 | return indicatePessimisticFixpoint(); | ||||||||
| 3423 | } | ||||||||
| 3424 | return ChangeStatus::UNCHANGED; | ||||||||
| 3425 | } | ||||||||
| 3426 | |||||||||
| 3427 | /// See AbstractAttribute::manifest(...). | ||||||||
| 3428 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 3429 | Value &V = getAssociatedValue(); | ||||||||
| 3430 | if (auto *I = dyn_cast<Instruction>(&V)) { | ||||||||
| 3431 | // If we get here we basically know the users are all dead. We check if | ||||||||
| 3432 | // isAssumedSideEffectFree returns true here again because it might not be | ||||||||
| 3433 | // the case and only the users are dead but the instruction (=call) is | ||||||||
| 3434 | // still needed. | ||||||||
| 3435 | if (isa<StoreInst>(I) || | ||||||||
| 3436 | (isAssumedSideEffectFree(A, I) && !isa<InvokeInst>(I))) { | ||||||||
| 3437 | A.deleteAfterManifest(*I); | ||||||||
| 3438 | return ChangeStatus::CHANGED; | ||||||||
| 3439 | } | ||||||||
| 3440 | } | ||||||||
| 3441 | if (V.use_empty()) | ||||||||
| 3442 | return ChangeStatus::UNCHANGED; | ||||||||
| 3443 | |||||||||
| 3444 | bool UsedAssumedInformation = false; | ||||||||
| 3445 | Optional<Constant *> C = | ||||||||
| 3446 | A.getAssumedConstant(V, *this, UsedAssumedInformation); | ||||||||
| 3447 | if (C.hasValue() && C.getValue()) | ||||||||
| 3448 | return ChangeStatus::UNCHANGED; | ||||||||
| 3449 | |||||||||
| 3450 | // Replace the value with undef as it is dead but keep droppable uses around | ||||||||
| 3451 | // as they provide information we don't want to give up on just yet. | ||||||||
| 3452 | UndefValue &UV = *UndefValue::get(V.getType()); | ||||||||
| 3453 | bool AnyChange = | ||||||||
| 3454 | A.changeValueAfterManifest(V, UV, /* ChangeDropppable */ false); | ||||||||
| 3455 | return AnyChange ? ChangeStatus::CHANGED : ChangeStatus::UNCHANGED; | ||||||||
| 3456 | } | ||||||||
| 3457 | |||||||||
| 3458 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3459 | void trackStatistics() const override { | ||||||||
| 3460 | STATS_DECLTRACK_FLOATING_ATTR(IsDead){ static llvm::Statistic NumIRFloating_IsDead = {"attributor" , "NumIRFloating_IsDead", ("Number of floating values known to be '" "IsDead" "'")};; ++(NumIRFloating_IsDead); } | ||||||||
| 3461 | } | ||||||||
| 3462 | }; | ||||||||
| 3463 | |||||||||
| 3464 | struct AAIsDeadArgument : public AAIsDeadFloating { | ||||||||
| 3465 | AAIsDeadArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 3466 | : AAIsDeadFloating(IRP, A) {} | ||||||||
| 3467 | |||||||||
| 3468 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3469 | void initialize(Attributor &A) override { | ||||||||
| 3470 | if (!A.isFunctionIPOAmendable(*getAnchorScope())) | ||||||||
| 3471 | indicatePessimisticFixpoint(); | ||||||||
| 3472 | } | ||||||||
| 3473 | |||||||||
| 3474 | /// See AbstractAttribute::manifest(...). | ||||||||
| 3475 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 3476 | ChangeStatus Changed = AAIsDeadFloating::manifest(A); | ||||||||
| 3477 | Argument &Arg = *getAssociatedArgument(); | ||||||||
| 3478 | if (A.isValidFunctionSignatureRewrite(Arg, /* ReplacementTypes */ {})) | ||||||||
| 3479 | if (A.registerFunctionSignatureRewrite( | ||||||||
| 3480 | Arg, /* ReplacementTypes */ {}, | ||||||||
| 3481 | Attributor::ArgumentReplacementInfo::CalleeRepairCBTy{}, | ||||||||
| 3482 | Attributor::ArgumentReplacementInfo::ACSRepairCBTy{})) { | ||||||||
| 3483 | Arg.dropDroppableUses(); | ||||||||
| 3484 | return ChangeStatus::CHANGED; | ||||||||
| 3485 | } | ||||||||
| 3486 | return Changed; | ||||||||
| 3487 | } | ||||||||
| 3488 | |||||||||
| 3489 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3490 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(IsDead){ static llvm::Statistic NumIRArguments_IsDead = {"attributor" , "NumIRArguments_IsDead", ("Number of " "arguments" " marked '" "IsDead" "'")};; ++(NumIRArguments_IsDead); } } | ||||||||
| 3491 | }; | ||||||||
| 3492 | |||||||||
| 3493 | struct AAIsDeadCallSiteArgument : public AAIsDeadValueImpl { | ||||||||
| 3494 | AAIsDeadCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 3495 | : AAIsDeadValueImpl(IRP, A) {} | ||||||||
| 3496 | |||||||||
| 3497 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3498 | void initialize(Attributor &A) override { | ||||||||
| 3499 | if (isa<UndefValue>(getAssociatedValue())) | ||||||||
| 3500 | indicatePessimisticFixpoint(); | ||||||||
| 3501 | } | ||||||||
| 3502 | |||||||||
| 3503 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3504 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3505 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 3506 | // call site specific liveness information and then it makes | ||||||||
| 3507 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 3508 | // redirecting requests to the callee argument. | ||||||||
| 3509 | Argument *Arg = getAssociatedArgument(); | ||||||||
| 3510 | if (!Arg) | ||||||||
| 3511 | return indicatePessimisticFixpoint(); | ||||||||
| 3512 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||||||
| 3513 | auto &ArgAA = A.getAAFor<AAIsDead>(*this, ArgPos, DepClassTy::REQUIRED); | ||||||||
| 3514 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||||||
| 3515 | } | ||||||||
| 3516 | |||||||||
| 3517 | /// See AbstractAttribute::manifest(...). | ||||||||
| 3518 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 3519 | CallBase &CB = cast<CallBase>(getAnchorValue()); | ||||||||
| 3520 | Use &U = CB.getArgOperandUse(getCallSiteArgNo()); | ||||||||
| 3521 | assert(!isa<UndefValue>(U.get()) &&((void)0) | ||||||||
| 3522 | "Expected undef values to be filtered out!")((void)0); | ||||||||
| 3523 | UndefValue &UV = *UndefValue::get(U->getType()); | ||||||||
| 3524 | if (A.changeUseAfterManifest(U, UV)) | ||||||||
| 3525 | return ChangeStatus::CHANGED; | ||||||||
| 3526 | return ChangeStatus::UNCHANGED; | ||||||||
| 3527 | } | ||||||||
| 3528 | |||||||||
| 3529 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3530 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(IsDead){ static llvm::Statistic NumIRCSArguments_IsDead = {"attributor" , "NumIRCSArguments_IsDead", ("Number of " "call site arguments" " marked '" "IsDead" "'")};; ++(NumIRCSArguments_IsDead); } } | ||||||||
| 3531 | }; | ||||||||
| 3532 | |||||||||
| 3533 | struct AAIsDeadCallSiteReturned : public AAIsDeadFloating { | ||||||||
| 3534 | AAIsDeadCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 3535 | : AAIsDeadFloating(IRP, A), IsAssumedSideEffectFree(true) {} | ||||||||
| 3536 | |||||||||
| 3537 | /// See AAIsDead::isAssumedDead(). | ||||||||
| 3538 | bool isAssumedDead() const override { | ||||||||
| 3539 | return AAIsDeadFloating::isAssumedDead() && IsAssumedSideEffectFree; | ||||||||
| 3540 | } | ||||||||
| 3541 | |||||||||
| 3542 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3543 | void initialize(Attributor &A) override { | ||||||||
| 3544 | if (isa<UndefValue>(getAssociatedValue())) { | ||||||||
| 3545 | indicatePessimisticFixpoint(); | ||||||||
| 3546 | return; | ||||||||
| 3547 | } | ||||||||
| 3548 | |||||||||
| 3549 | // We track this separately as a secondary state. | ||||||||
| 3550 | IsAssumedSideEffectFree = isAssumedSideEffectFree(A, getCtxI()); | ||||||||
| 3551 | } | ||||||||
| 3552 | |||||||||
| 3553 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3554 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3555 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 3556 | if (IsAssumedSideEffectFree && !isAssumedSideEffectFree(A, getCtxI())) { | ||||||||
| 3557 | IsAssumedSideEffectFree = false; | ||||||||
| 3558 | Changed = ChangeStatus::CHANGED; | ||||||||
| 3559 | } | ||||||||
| 3560 | if (!areAllUsesAssumedDead(A, getAssociatedValue())) | ||||||||
| 3561 | return indicatePessimisticFixpoint(); | ||||||||
| 3562 | return Changed; | ||||||||
| 3563 | } | ||||||||
| 3564 | |||||||||
| 3565 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3566 | void trackStatistics() const override { | ||||||||
| 3567 | if (IsAssumedSideEffectFree) | ||||||||
| 3568 | STATS_DECLTRACK_CSRET_ATTR(IsDead){ static llvm::Statistic NumIRCSReturn_IsDead = {"attributor" , "NumIRCSReturn_IsDead", ("Number of " "call site returns" " marked '" "IsDead" "'")};; ++(NumIRCSReturn_IsDead); } | ||||||||
| 3569 | else | ||||||||
| 3570 | STATS_DECLTRACK_CSRET_ATTR(UnusedResult){ static llvm::Statistic NumIRCSReturn_UnusedResult = {"attributor" , "NumIRCSReturn_UnusedResult", ("Number of " "call site returns" " marked '" "UnusedResult" "'")};; ++(NumIRCSReturn_UnusedResult ); } | ||||||||
| 3571 | } | ||||||||
| 3572 | |||||||||
| 3573 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 3574 | const std::string getAsStr() const override { | ||||||||
| 3575 | return isAssumedDead() | ||||||||
| 3576 | ? "assumed-dead" | ||||||||
| 3577 | : (getAssumed() ? "assumed-dead-users" : "assumed-live"); | ||||||||
| 3578 | } | ||||||||
| 3579 | |||||||||
| 3580 | private: | ||||||||
| 3581 | bool IsAssumedSideEffectFree; | ||||||||
| 3582 | }; | ||||||||
| 3583 | |||||||||
| 3584 | struct AAIsDeadReturned : public AAIsDeadValueImpl { | ||||||||
| 3585 | AAIsDeadReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 3586 | : AAIsDeadValueImpl(IRP, A) {} | ||||||||
| 3587 | |||||||||
| 3588 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3589 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 3590 | |||||||||
| 3591 | bool UsedAssumedInformation = false; | ||||||||
| 3592 | A.checkForAllInstructions([](Instruction &) { return true; }, *this, | ||||||||
| 3593 | {Instruction::Ret}, UsedAssumedInformation); | ||||||||
| 3594 | |||||||||
| 3595 | auto PredForCallSite = [&](AbstractCallSite ACS) { | ||||||||
| 3596 | if (ACS.isCallbackCall() || !ACS.getInstruction()) | ||||||||
| 3597 | return false; | ||||||||
| 3598 | return areAllUsesAssumedDead(A, *ACS.getInstruction()); | ||||||||
| 3599 | }; | ||||||||
| 3600 | |||||||||
| 3601 | bool AllCallSitesKnown; | ||||||||
| 3602 | if (!A.checkForAllCallSites(PredForCallSite, *this, true, | ||||||||
| 3603 | AllCallSitesKnown)) | ||||||||
| 3604 | return indicatePessimisticFixpoint(); | ||||||||
| 3605 | |||||||||
| 3606 | return ChangeStatus::UNCHANGED; | ||||||||
| 3607 | } | ||||||||
| 3608 | |||||||||
| 3609 | /// See AbstractAttribute::manifest(...). | ||||||||
| 3610 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 3611 | // TODO: Rewrite the signature to return void? | ||||||||
| 3612 | bool AnyChange = false; | ||||||||
| 3613 | UndefValue &UV = *UndefValue::get(getAssociatedFunction()->getReturnType()); | ||||||||
| 3614 | auto RetInstPred = [&](Instruction &I) { | ||||||||
| 3615 | ReturnInst &RI = cast<ReturnInst>(I); | ||||||||
| 3616 | if (!isa<UndefValue>(RI.getReturnValue())) | ||||||||
| 3617 | AnyChange |= A.changeUseAfterManifest(RI.getOperandUse(0), UV); | ||||||||
| 3618 | return true; | ||||||||
| 3619 | }; | ||||||||
| 3620 | bool UsedAssumedInformation = false; | ||||||||
| 3621 | A.checkForAllInstructions(RetInstPred, *this, {Instruction::Ret}, | ||||||||
| 3622 | UsedAssumedInformation); | ||||||||
| 3623 | return AnyChange ? ChangeStatus::CHANGED : ChangeStatus::UNCHANGED; | ||||||||
| 3624 | } | ||||||||
| 3625 | |||||||||
| 3626 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3627 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(IsDead){ static llvm::Statistic NumIRFunctionReturn_IsDead = {"attributor" , "NumIRFunctionReturn_IsDead", ("Number of " "function returns" " marked '" "IsDead" "'")};; ++(NumIRFunctionReturn_IsDead); } } | ||||||||
| 3628 | }; | ||||||||
| 3629 | |||||||||
| 3630 | struct AAIsDeadFunction : public AAIsDead { | ||||||||
| 3631 | AAIsDeadFunction(const IRPosition &IRP, Attributor &A) : AAIsDead(IRP, A) {} | ||||||||
| 3632 | |||||||||
| 3633 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3634 | void initialize(Attributor &A) override { | ||||||||
| 3635 | const Function *F = getAnchorScope(); | ||||||||
| 3636 | if (F && !F->isDeclaration()) { | ||||||||
| 3637 | // We only want to compute liveness once. If the function is not part of | ||||||||
| 3638 | // the SCC, skip it. | ||||||||
| 3639 | if (A.isRunOn(*const_cast<Function *>(F))) { | ||||||||
| 3640 | ToBeExploredFrom.insert(&F->getEntryBlock().front()); | ||||||||
| 3641 | assumeLive(A, F->getEntryBlock()); | ||||||||
| 3642 | } else { | ||||||||
| 3643 | indicatePessimisticFixpoint(); | ||||||||
| 3644 | } | ||||||||
| 3645 | } | ||||||||
| 3646 | } | ||||||||
| 3647 | |||||||||
| 3648 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 3649 | const std::string getAsStr() const override { | ||||||||
| 3650 | return "Live[#BB " + std::to_string(AssumedLiveBlocks.size()) + "/" + | ||||||||
| 3651 | std::to_string(getAnchorScope()->size()) + "][#TBEP " + | ||||||||
| 3652 | std::to_string(ToBeExploredFrom.size()) + "][#KDE " + | ||||||||
| 3653 | std::to_string(KnownDeadEnds.size()) + "]"; | ||||||||
| 3654 | } | ||||||||
| 3655 | |||||||||
| 3656 | /// See AbstractAttribute::manifest(...). | ||||||||
| 3657 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 3658 | assert(getState().isValidState() &&((void)0) | ||||||||
| 3659 | "Attempted to manifest an invalid state!")((void)0); | ||||||||
| 3660 | |||||||||
| 3661 | ChangeStatus HasChanged = ChangeStatus::UNCHANGED; | ||||||||
| 3662 | Function &F = *getAnchorScope(); | ||||||||
| 3663 | |||||||||
| 3664 | if (AssumedLiveBlocks.empty()) { | ||||||||
| 3665 | A.deleteAfterManifest(F); | ||||||||
| 3666 | return ChangeStatus::CHANGED; | ||||||||
| 3667 | } | ||||||||
| 3668 | |||||||||
| 3669 | // Flag to determine if we can change an invoke to a call assuming the | ||||||||
| 3670 | // callee is nounwind. This is not possible if the personality of the | ||||||||
| 3671 | // function allows to catch asynchronous exceptions. | ||||||||
| 3672 | bool Invoke2CallAllowed = !mayCatchAsynchronousExceptions(F); | ||||||||
| 3673 | |||||||||
| 3674 | KnownDeadEnds.set_union(ToBeExploredFrom); | ||||||||
| 3675 | for (const Instruction *DeadEndI : KnownDeadEnds) { | ||||||||
| 3676 | auto *CB = dyn_cast<CallBase>(DeadEndI); | ||||||||
| 3677 | if (!CB) | ||||||||
| 3678 | continue; | ||||||||
| 3679 | const auto &NoReturnAA = A.getAndUpdateAAFor<AANoReturn>( | ||||||||
| 3680 | *this, IRPosition::callsite_function(*CB), DepClassTy::OPTIONAL); | ||||||||
| 3681 | bool MayReturn = !NoReturnAA.isAssumedNoReturn(); | ||||||||
| 3682 | if (MayReturn && (!Invoke2CallAllowed || !isa<InvokeInst>(CB))) | ||||||||
| 3683 | continue; | ||||||||
| 3684 | |||||||||
| 3685 | if (auto *II = dyn_cast<InvokeInst>(DeadEndI)) | ||||||||
| 3686 | A.registerInvokeWithDeadSuccessor(const_cast<InvokeInst &>(*II)); | ||||||||
| 3687 | else | ||||||||
| 3688 | A.changeToUnreachableAfterManifest( | ||||||||
| 3689 | const_cast<Instruction *>(DeadEndI->getNextNode())); | ||||||||
| 3690 | HasChanged = ChangeStatus::CHANGED; | ||||||||
| 3691 | } | ||||||||
| 3692 | |||||||||
| 3693 | STATS_DECL(AAIsDead, BasicBlock, "Number of dead basic blocks deleted.")static llvm::Statistic NumIRBasicBlock_AAIsDead = {"attributor" , "NumIRBasicBlock_AAIsDead", "Number of dead basic blocks deleted." };;; | ||||||||
| 3694 | for (BasicBlock &BB : F) | ||||||||
| 3695 | if (!AssumedLiveBlocks.count(&BB)) { | ||||||||
| 3696 | A.deleteAfterManifest(BB); | ||||||||
| 3697 | ++BUILD_STAT_NAME(AAIsDead, BasicBlock)NumIRBasicBlock_AAIsDead; | ||||||||
| 3698 | } | ||||||||
| 3699 | |||||||||
| 3700 | return HasChanged; | ||||||||
| 3701 | } | ||||||||
| 3702 | |||||||||
| 3703 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 3704 | ChangeStatus updateImpl(Attributor &A) override; | ||||||||
| 3705 | |||||||||
| 3706 | bool isEdgeDead(const BasicBlock *From, const BasicBlock *To) const override { | ||||||||
| 3707 | return !AssumedLiveEdges.count(std::make_pair(From, To)); | ||||||||
| 3708 | } | ||||||||
| 3709 | |||||||||
| 3710 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 3711 | void trackStatistics() const override {} | ||||||||
| 3712 | |||||||||
| 3713 | /// Returns true if the function is assumed dead. | ||||||||
| 3714 | bool isAssumedDead() const override { return false; } | ||||||||
| 3715 | |||||||||
| 3716 | /// See AAIsDead::isKnownDead(). | ||||||||
| 3717 | bool isKnownDead() const override { return false; } | ||||||||
| 3718 | |||||||||
| 3719 | /// See AAIsDead::isAssumedDead(BasicBlock *). | ||||||||
| 3720 | bool isAssumedDead(const BasicBlock *BB) const override { | ||||||||
| 3721 | assert(BB->getParent() == getAnchorScope() &&((void)0) | ||||||||
| 3722 | "BB must be in the same anchor scope function.")((void)0); | ||||||||
| 3723 | |||||||||
| 3724 | if (!getAssumed()) | ||||||||
| 3725 | return false; | ||||||||
| 3726 | return !AssumedLiveBlocks.count(BB); | ||||||||
| 3727 | } | ||||||||
| 3728 | |||||||||
| 3729 | /// See AAIsDead::isKnownDead(BasicBlock *). | ||||||||
| 3730 | bool isKnownDead(const BasicBlock *BB) const override { | ||||||||
| 3731 | return getKnown() && isAssumedDead(BB); | ||||||||
| 3732 | } | ||||||||
| 3733 | |||||||||
| 3734 | /// See AAIsDead::isAssumed(Instruction *I). | ||||||||
| 3735 | bool isAssumedDead(const Instruction *I) const override { | ||||||||
| 3736 | assert(I->getParent()->getParent() == getAnchorScope() &&((void)0) | ||||||||
| 3737 | "Instruction must be in the same anchor scope function.")((void)0); | ||||||||
| 3738 | |||||||||
| 3739 | if (!getAssumed()) | ||||||||
| 3740 | return false; | ||||||||
| 3741 | |||||||||
| 3742 | // If it is not in AssumedLiveBlocks then it for sure dead. | ||||||||
| 3743 | // Otherwise, it can still be after noreturn call in a live block. | ||||||||
| 3744 | if (!AssumedLiveBlocks.count(I->getParent())) | ||||||||
| 3745 | return true; | ||||||||
| 3746 | |||||||||
| 3747 | // If it is not after a liveness barrier it is live. | ||||||||
| 3748 | const Instruction *PrevI = I->getPrevNode(); | ||||||||
| 3749 | while (PrevI) { | ||||||||
| 3750 | if (KnownDeadEnds.count(PrevI) || ToBeExploredFrom.count(PrevI)) | ||||||||
| 3751 | return true; | ||||||||
| 3752 | PrevI = PrevI->getPrevNode(); | ||||||||
| 3753 | } | ||||||||
| 3754 | return false; | ||||||||
| 3755 | } | ||||||||
| 3756 | |||||||||
| 3757 | /// See AAIsDead::isKnownDead(Instruction *I). | ||||||||
| 3758 | bool isKnownDead(const Instruction *I) const override { | ||||||||
| 3759 | return getKnown() && isAssumedDead(I); | ||||||||
| 3760 | } | ||||||||
| 3761 | |||||||||
| 3762 | /// Assume \p BB is (partially) live now and indicate to the Attributor \p A | ||||||||
| 3763 | /// that internal function called from \p BB should now be looked at. | ||||||||
| 3764 | bool assumeLive(Attributor &A, const BasicBlock &BB) { | ||||||||
| 3765 | if (!AssumedLiveBlocks.insert(&BB).second) | ||||||||
| 3766 | return false; | ||||||||
| 3767 | |||||||||
| 3768 | // We assume that all of BB is (probably) live now and if there are calls to | ||||||||
| 3769 | // internal functions we will assume that those are now live as well. This | ||||||||
| 3770 | // is a performance optimization for blocks with calls to a lot of internal | ||||||||
| 3771 | // functions. It can however cause dead functions to be treated as live. | ||||||||
| 3772 | for (const Instruction &I : BB) | ||||||||
| 3773 | if (const auto *CB = dyn_cast<CallBase>(&I)) | ||||||||
| 3774 | if (const Function *F = CB->getCalledFunction()) | ||||||||
| 3775 | if (F->hasLocalLinkage()) | ||||||||
| 3776 | A.markLiveInternalFunction(*F); | ||||||||
| 3777 | return true; | ||||||||
| 3778 | } | ||||||||
| 3779 | |||||||||
| 3780 | /// Collection of instructions that need to be explored again, e.g., we | ||||||||
| 3781 | /// did assume they do not transfer control to (one of their) successors. | ||||||||
| 3782 | SmallSetVector<const Instruction *, 8> ToBeExploredFrom; | ||||||||
| 3783 | |||||||||
| 3784 | /// Collection of instructions that are known to not transfer control. | ||||||||
| 3785 | SmallSetVector<const Instruction *, 8> KnownDeadEnds; | ||||||||
| 3786 | |||||||||
| 3787 | /// Collection of all assumed live edges | ||||||||
| 3788 | DenseSet<std::pair<const BasicBlock *, const BasicBlock *>> AssumedLiveEdges; | ||||||||
| 3789 | |||||||||
| 3790 | /// Collection of all assumed live BasicBlocks. | ||||||||
| 3791 | DenseSet<const BasicBlock *> AssumedLiveBlocks; | ||||||||
| 3792 | }; | ||||||||
| 3793 | |||||||||
| 3794 | static bool | ||||||||
| 3795 | identifyAliveSuccessors(Attributor &A, const CallBase &CB, | ||||||||
| 3796 | AbstractAttribute &AA, | ||||||||
| 3797 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||||||
| 3798 | const IRPosition &IPos = IRPosition::callsite_function(CB); | ||||||||
| 3799 | |||||||||
| 3800 | const auto &NoReturnAA = | ||||||||
| 3801 | A.getAndUpdateAAFor<AANoReturn>(AA, IPos, DepClassTy::OPTIONAL); | ||||||||
| 3802 | if (NoReturnAA.isAssumedNoReturn()) | ||||||||
| 3803 | return !NoReturnAA.isKnownNoReturn(); | ||||||||
| 3804 | if (CB.isTerminator()) | ||||||||
| 3805 | AliveSuccessors.push_back(&CB.getSuccessor(0)->front()); | ||||||||
| 3806 | else | ||||||||
| 3807 | AliveSuccessors.push_back(CB.getNextNode()); | ||||||||
| 3808 | return false; | ||||||||
| 3809 | } | ||||||||
| 3810 | |||||||||
| 3811 | static bool | ||||||||
| 3812 | identifyAliveSuccessors(Attributor &A, const InvokeInst &II, | ||||||||
| 3813 | AbstractAttribute &AA, | ||||||||
| 3814 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||||||
| 3815 | bool UsedAssumedInformation = | ||||||||
| 3816 | identifyAliveSuccessors(A, cast<CallBase>(II), AA, AliveSuccessors); | ||||||||
| 3817 | |||||||||
| 3818 | // First, determine if we can change an invoke to a call assuming the | ||||||||
| 3819 | // callee is nounwind. This is not possible if the personality of the | ||||||||
| 3820 | // function allows to catch asynchronous exceptions. | ||||||||
| 3821 | if (AAIsDeadFunction::mayCatchAsynchronousExceptions(*II.getFunction())) { | ||||||||
| 3822 | AliveSuccessors.push_back(&II.getUnwindDest()->front()); | ||||||||
| 3823 | } else { | ||||||||
| 3824 | const IRPosition &IPos = IRPosition::callsite_function(II); | ||||||||
| 3825 | const auto &AANoUnw = | ||||||||
| 3826 | A.getAndUpdateAAFor<AANoUnwind>(AA, IPos, DepClassTy::OPTIONAL); | ||||||||
| 3827 | if (AANoUnw.isAssumedNoUnwind()) { | ||||||||
| 3828 | UsedAssumedInformation |= !AANoUnw.isKnownNoUnwind(); | ||||||||
| 3829 | } else { | ||||||||
| 3830 | AliveSuccessors.push_back(&II.getUnwindDest()->front()); | ||||||||
| 3831 | } | ||||||||
| 3832 | } | ||||||||
| 3833 | return UsedAssumedInformation; | ||||||||
| 3834 | } | ||||||||
| 3835 | |||||||||
| 3836 | static bool | ||||||||
| 3837 | identifyAliveSuccessors(Attributor &A, const BranchInst &BI, | ||||||||
| 3838 | AbstractAttribute &AA, | ||||||||
| 3839 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||||||
| 3840 | bool UsedAssumedInformation = false; | ||||||||
| 3841 | if (BI.getNumSuccessors() == 1) { | ||||||||
| 3842 | AliveSuccessors.push_back(&BI.getSuccessor(0)->front()); | ||||||||
| 3843 | } else { | ||||||||
| 3844 | Optional<Constant *> C = | ||||||||
| 3845 | A.getAssumedConstant(*BI.getCondition(), AA, UsedAssumedInformation); | ||||||||
| 3846 | if (!C.hasValue() || isa_and_nonnull<UndefValue>(C.getValue())) { | ||||||||
| 3847 | // No value yet, assume both edges are dead. | ||||||||
| 3848 | } else if (isa_and_nonnull<ConstantInt>(*C)) { | ||||||||
| 3849 | const BasicBlock *SuccBB = | ||||||||
| 3850 | BI.getSuccessor(1 - cast<ConstantInt>(*C)->getValue().getZExtValue()); | ||||||||
| 3851 | AliveSuccessors.push_back(&SuccBB->front()); | ||||||||
| 3852 | } else { | ||||||||
| 3853 | AliveSuccessors.push_back(&BI.getSuccessor(0)->front()); | ||||||||
| 3854 | AliveSuccessors.push_back(&BI.getSuccessor(1)->front()); | ||||||||
| 3855 | UsedAssumedInformation = false; | ||||||||
| 3856 | } | ||||||||
| 3857 | } | ||||||||
| 3858 | return UsedAssumedInformation; | ||||||||
| 3859 | } | ||||||||
| 3860 | |||||||||
| 3861 | static bool | ||||||||
| 3862 | identifyAliveSuccessors(Attributor &A, const SwitchInst &SI, | ||||||||
| 3863 | AbstractAttribute &AA, | ||||||||
| 3864 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||||||
| 3865 | bool UsedAssumedInformation = false; | ||||||||
| 3866 | Optional<Constant *> C = | ||||||||
| 3867 | A.getAssumedConstant(*SI.getCondition(), AA, UsedAssumedInformation); | ||||||||
| 3868 | if (!C.hasValue() || isa_and_nonnull<UndefValue>(C.getValue())) { | ||||||||
| 3869 | // No value yet, assume all edges are dead. | ||||||||
| 3870 | } else if (isa_and_nonnull<ConstantInt>(C.getValue())) { | ||||||||
| 3871 | for (auto &CaseIt : SI.cases()) { | ||||||||
| 3872 | if (CaseIt.getCaseValue() == C.getValue()) { | ||||||||
| 3873 | AliveSuccessors.push_back(&CaseIt.getCaseSuccessor()->front()); | ||||||||
| 3874 | return UsedAssumedInformation; | ||||||||
| 3875 | } | ||||||||
| 3876 | } | ||||||||
| 3877 | AliveSuccessors.push_back(&SI.getDefaultDest()->front()); | ||||||||
| 3878 | return UsedAssumedInformation; | ||||||||
| 3879 | } else { | ||||||||
| 3880 | for (const BasicBlock *SuccBB : successors(SI.getParent())) | ||||||||
| 3881 | AliveSuccessors.push_back(&SuccBB->front()); | ||||||||
| 3882 | } | ||||||||
| 3883 | return UsedAssumedInformation; | ||||||||
| 3884 | } | ||||||||
| 3885 | |||||||||
| 3886 | ChangeStatus AAIsDeadFunction::updateImpl(Attributor &A) { | ||||||||
| 3887 | ChangeStatus Change = ChangeStatus::UNCHANGED; | ||||||||
| 3888 | |||||||||
| 3889 | LLVM_DEBUG(dbgs() << "[AAIsDead] Live [" << AssumedLiveBlocks.size() << "/"do { } while (false) | ||||||||
| 3890 | << getAnchorScope()->size() << "] BBs and "do { } while (false) | ||||||||
| 3891 | << ToBeExploredFrom.size() << " exploration points and "do { } while (false) | ||||||||
| 3892 | << KnownDeadEnds.size() << " known dead ends\n")do { } while (false); | ||||||||
| 3893 | |||||||||
| 3894 | // Copy and clear the list of instructions we need to explore from. It is | ||||||||
| 3895 | // refilled with instructions the next update has to look at. | ||||||||
| 3896 | SmallVector<const Instruction *, 8> Worklist(ToBeExploredFrom.begin(), | ||||||||
| 3897 | ToBeExploredFrom.end()); | ||||||||
| 3898 | decltype(ToBeExploredFrom) NewToBeExploredFrom; | ||||||||
| 3899 | |||||||||
| 3900 | SmallVector<const Instruction *, 8> AliveSuccessors; | ||||||||
| 3901 | while (!Worklist.empty()) { | ||||||||
| 3902 | const Instruction *I = Worklist.pop_back_val(); | ||||||||
| 3903 | LLVM_DEBUG(dbgs() << "[AAIsDead] Exploration inst: " << *I << "\n")do { } while (false); | ||||||||
| 3904 | |||||||||
| 3905 | // Fast forward for uninteresting instructions. We could look for UB here | ||||||||
| 3906 | // though. | ||||||||
| 3907 | while (!I->isTerminator() && !isa<CallBase>(I)) | ||||||||
| 3908 | I = I->getNextNode(); | ||||||||
| 3909 | |||||||||
| 3910 | AliveSuccessors.clear(); | ||||||||
| 3911 | |||||||||
| 3912 | bool UsedAssumedInformation = false; | ||||||||
| 3913 | switch (I->getOpcode()) { | ||||||||
| 3914 | // TODO: look for (assumed) UB to backwards propagate "deadness". | ||||||||
| 3915 | default: | ||||||||
| 3916 | assert(I->isTerminator() &&((void)0) | ||||||||
| 3917 | "Expected non-terminators to be handled already!")((void)0); | ||||||||
| 3918 | for (const BasicBlock *SuccBB : successors(I->getParent())) | ||||||||
| 3919 | AliveSuccessors.push_back(&SuccBB->front()); | ||||||||
| 3920 | break; | ||||||||
| 3921 | case Instruction::Call: | ||||||||
| 3922 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<CallInst>(*I), | ||||||||
| 3923 | *this, AliveSuccessors); | ||||||||
| 3924 | break; | ||||||||
| 3925 | case Instruction::Invoke: | ||||||||
| 3926 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<InvokeInst>(*I), | ||||||||
| 3927 | *this, AliveSuccessors); | ||||||||
| 3928 | break; | ||||||||
| 3929 | case Instruction::Br: | ||||||||
| 3930 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<BranchInst>(*I), | ||||||||
| 3931 | *this, AliveSuccessors); | ||||||||
| 3932 | break; | ||||||||
| 3933 | case Instruction::Switch: | ||||||||
| 3934 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<SwitchInst>(*I), | ||||||||
| 3935 | *this, AliveSuccessors); | ||||||||
| 3936 | break; | ||||||||
| 3937 | } | ||||||||
| 3938 | |||||||||
| 3939 | if (UsedAssumedInformation) { | ||||||||
| 3940 | NewToBeExploredFrom.insert(I); | ||||||||
| 3941 | } else if (AliveSuccessors.empty() || | ||||||||
| 3942 | (I->isTerminator() && | ||||||||
| 3943 | AliveSuccessors.size() < I->getNumSuccessors())) { | ||||||||
| 3944 | if (KnownDeadEnds.insert(I)) | ||||||||
| 3945 | Change = ChangeStatus::CHANGED; | ||||||||
| 3946 | } | ||||||||
| 3947 | |||||||||
| 3948 | LLVM_DEBUG(dbgs() << "[AAIsDead] #AliveSuccessors: "do { } while (false) | ||||||||
| 3949 | << AliveSuccessors.size() << " UsedAssumedInformation: "do { } while (false) | ||||||||
| 3950 | << UsedAssumedInformation << "\n")do { } while (false); | ||||||||
| 3951 | |||||||||
| 3952 | for (const Instruction *AliveSuccessor : AliveSuccessors) { | ||||||||
| 3953 | if (!I->isTerminator()) { | ||||||||
| 3954 | assert(AliveSuccessors.size() == 1 &&((void)0) | ||||||||
| 3955 | "Non-terminator expected to have a single successor!")((void)0); | ||||||||
| 3956 | Worklist.push_back(AliveSuccessor); | ||||||||
| 3957 | } else { | ||||||||
| 3958 | // record the assumed live edge | ||||||||
| 3959 | auto Edge = std::make_pair(I->getParent(), AliveSuccessor->getParent()); | ||||||||
| 3960 | if (AssumedLiveEdges.insert(Edge).second) | ||||||||
| 3961 | Change = ChangeStatus::CHANGED; | ||||||||
| 3962 | if (assumeLive(A, *AliveSuccessor->getParent())) | ||||||||
| 3963 | Worklist.push_back(AliveSuccessor); | ||||||||
| 3964 | } | ||||||||
| 3965 | } | ||||||||
| 3966 | } | ||||||||
| 3967 | |||||||||
| 3968 | // Check if the content of ToBeExploredFrom changed, ignore the order. | ||||||||
| 3969 | if (NewToBeExploredFrom.size() != ToBeExploredFrom.size() || | ||||||||
| 3970 | llvm::any_of(NewToBeExploredFrom, [&](const Instruction *I) { | ||||||||
| 3971 | return !ToBeExploredFrom.count(I); | ||||||||
| 3972 | })) { | ||||||||
| 3973 | Change = ChangeStatus::CHANGED; | ||||||||
| 3974 | ToBeExploredFrom = std::move(NewToBeExploredFrom); | ||||||||
| 3975 | } | ||||||||
| 3976 | |||||||||
| 3977 | // If we know everything is live there is no need to query for liveness. | ||||||||
| 3978 | // Instead, indicating a pessimistic fixpoint will cause the state to be | ||||||||
| 3979 | // "invalid" and all queries to be answered conservatively without lookups. | ||||||||
| 3980 | // To be in this state we have to (1) finished the exploration and (3) not | ||||||||
| 3981 | // discovered any non-trivial dead end and (2) not ruled unreachable code | ||||||||
| 3982 | // dead. | ||||||||
| 3983 | if (ToBeExploredFrom.empty() && | ||||||||
| 3984 | getAnchorScope()->size() == AssumedLiveBlocks.size() && | ||||||||
| 3985 | llvm::all_of(KnownDeadEnds, [](const Instruction *DeadEndI) { | ||||||||
| 3986 | return DeadEndI->isTerminator() && DeadEndI->getNumSuccessors() == 0; | ||||||||
| 3987 | })) | ||||||||
| 3988 | return indicatePessimisticFixpoint(); | ||||||||
| 3989 | return Change; | ||||||||
| 3990 | } | ||||||||
| 3991 | |||||||||
| 3992 | /// Liveness information for a call sites. | ||||||||
| 3993 | struct AAIsDeadCallSite final : AAIsDeadFunction { | ||||||||
| 3994 | AAIsDeadCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 3995 | : AAIsDeadFunction(IRP, A) {} | ||||||||
| 3996 | |||||||||
| 3997 | /// See AbstractAttribute::initialize(...). | ||||||||
| 3998 | void initialize(Attributor &A) override { | ||||||||
| 3999 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 4000 | // call site specific liveness information and then it makes | ||||||||
| 4001 | // sense to specialize attributes for call sites instead of | ||||||||
| 4002 | // redirecting requests to the callee. | ||||||||
| 4003 | llvm_unreachable("Abstract attributes for liveness are not "__builtin_unreachable() | ||||||||
| 4004 | "supported for call sites yet!")__builtin_unreachable(); | ||||||||
| 4005 | } | ||||||||
| 4006 | |||||||||
| 4007 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 4008 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 4009 | return indicatePessimisticFixpoint(); | ||||||||
| 4010 | } | ||||||||
| 4011 | |||||||||
| 4012 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4013 | void trackStatistics() const override {} | ||||||||
| 4014 | }; | ||||||||
| 4015 | |||||||||
| 4016 | /// -------------------- Dereferenceable Argument Attribute -------------------- | ||||||||
| 4017 | |||||||||
| 4018 | struct AADereferenceableImpl : AADereferenceable { | ||||||||
| 4019 | AADereferenceableImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 4020 | : AADereferenceable(IRP, A) {} | ||||||||
| 4021 | using StateType = DerefState; | ||||||||
| 4022 | |||||||||
| 4023 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4024 | void initialize(Attributor &A) override { | ||||||||
| 4025 | SmallVector<Attribute, 4> Attrs; | ||||||||
| 4026 | getAttrs({Attribute::Dereferenceable, Attribute::DereferenceableOrNull}, | ||||||||
| 4027 | Attrs, /* IgnoreSubsumingPositions */ false, &A); | ||||||||
| 4028 | for (const Attribute &Attr : Attrs) | ||||||||
| 4029 | takeKnownDerefBytesMaximum(Attr.getValueAsInt()); | ||||||||
| 4030 | |||||||||
| 4031 | const IRPosition &IRP = this->getIRPosition(); | ||||||||
| 4032 | NonNullAA = &A.getAAFor<AANonNull>(*this, IRP, DepClassTy::NONE); | ||||||||
| 4033 | |||||||||
| 4034 | bool CanBeNull, CanBeFreed; | ||||||||
| 4035 | takeKnownDerefBytesMaximum( | ||||||||
| 4036 | IRP.getAssociatedValue().getPointerDereferenceableBytes( | ||||||||
| 4037 | A.getDataLayout(), CanBeNull, CanBeFreed)); | ||||||||
| 4038 | |||||||||
| 4039 | bool IsFnInterface = IRP.isFnInterfaceKind(); | ||||||||
| 4040 | Function *FnScope = IRP.getAnchorScope(); | ||||||||
| 4041 | if (IsFnInterface && (!FnScope || !A.isFunctionIPOAmendable(*FnScope))) { | ||||||||
| 4042 | indicatePessimisticFixpoint(); | ||||||||
| 4043 | return; | ||||||||
| 4044 | } | ||||||||
| 4045 | |||||||||
| 4046 | if (Instruction *CtxI = getCtxI()) | ||||||||
| 4047 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||||||
| 4048 | } | ||||||||
| 4049 | |||||||||
| 4050 | /// See AbstractAttribute::getState() | ||||||||
| 4051 | /// { | ||||||||
| 4052 | StateType &getState() override { return *this; } | ||||||||
| 4053 | const StateType &getState() const override { return *this; } | ||||||||
| 4054 | /// } | ||||||||
| 4055 | |||||||||
| 4056 | /// Helper function for collecting accessed bytes in must-be-executed-context | ||||||||
| 4057 | void addAccessedBytesForUse(Attributor &A, const Use *U, const Instruction *I, | ||||||||
| 4058 | DerefState &State) { | ||||||||
| 4059 | const Value *UseV = U->get(); | ||||||||
| 4060 | if (!UseV->getType()->isPointerTy()) | ||||||||
| 4061 | return; | ||||||||
| 4062 | |||||||||
| 4063 | Type *PtrTy = UseV->getType(); | ||||||||
| 4064 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 4065 | int64_t Offset; | ||||||||
| 4066 | if (const Value *Base = getBasePointerOfAccessPointerOperand( | ||||||||
| 4067 | I, Offset, DL, /*AllowNonInbounds*/ true)) { | ||||||||
| 4068 | if (Base == &getAssociatedValue() && | ||||||||
| 4069 | getPointerOperand(I, /* AllowVolatile */ false) == UseV) { | ||||||||
| 4070 | uint64_t Size = DL.getTypeStoreSize(PtrTy->getPointerElementType()); | ||||||||
| 4071 | State.addAccessedBytes(Offset, Size); | ||||||||
| 4072 | } | ||||||||
| 4073 | } | ||||||||
| 4074 | } | ||||||||
| 4075 | |||||||||
| 4076 | /// See followUsesInMBEC | ||||||||
| 4077 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||||||
| 4078 | AADereferenceable::StateType &State) { | ||||||||
| 4079 | bool IsNonNull = false; | ||||||||
| 4080 | bool TrackUse = false; | ||||||||
| 4081 | int64_t DerefBytes = getKnownNonNullAndDerefBytesForUse( | ||||||||
| 4082 | A, *this, getAssociatedValue(), U, I, IsNonNull, TrackUse); | ||||||||
| 4083 | LLVM_DEBUG(dbgs() << "[AADereferenceable] Deref bytes: " << DerefBytesdo { } while (false) | ||||||||
| 4084 | << " for instruction " << *I << "\n")do { } while (false); | ||||||||
| 4085 | |||||||||
| 4086 | addAccessedBytesForUse(A, U, I, State); | ||||||||
| 4087 | State.takeKnownDerefBytesMaximum(DerefBytes); | ||||||||
| 4088 | return TrackUse; | ||||||||
| 4089 | } | ||||||||
| 4090 | |||||||||
| 4091 | /// See AbstractAttribute::manifest(...). | ||||||||
| 4092 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 4093 | ChangeStatus Change = AADereferenceable::manifest(A); | ||||||||
| 4094 | if (isAssumedNonNull() && hasAttr(Attribute::DereferenceableOrNull)) { | ||||||||
| 4095 | removeAttrs({Attribute::DereferenceableOrNull}); | ||||||||
| 4096 | return ChangeStatus::CHANGED; | ||||||||
| 4097 | } | ||||||||
| 4098 | return Change; | ||||||||
| 4099 | } | ||||||||
| 4100 | |||||||||
| 4101 | void getDeducedAttributes(LLVMContext &Ctx, | ||||||||
| 4102 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||||||
| 4103 | // TODO: Add *_globally support | ||||||||
| 4104 | if (isAssumedNonNull()) | ||||||||
| 4105 | Attrs.emplace_back(Attribute::getWithDereferenceableBytes( | ||||||||
| 4106 | Ctx, getAssumedDereferenceableBytes())); | ||||||||
| 4107 | else | ||||||||
| 4108 | Attrs.emplace_back(Attribute::getWithDereferenceableOrNullBytes( | ||||||||
| 4109 | Ctx, getAssumedDereferenceableBytes())); | ||||||||
| 4110 | } | ||||||||
| 4111 | |||||||||
| 4112 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 4113 | const std::string getAsStr() const override { | ||||||||
| 4114 | if (!getAssumedDereferenceableBytes()) | ||||||||
| 4115 | return "unknown-dereferenceable"; | ||||||||
| 4116 | return std::string("dereferenceable") + | ||||||||
| 4117 | (isAssumedNonNull() ? "" : "_or_null") + | ||||||||
| 4118 | (isAssumedGlobal() ? "_globally" : "") + "<" + | ||||||||
| 4119 | std::to_string(getKnownDereferenceableBytes()) + "-" + | ||||||||
| 4120 | std::to_string(getAssumedDereferenceableBytes()) + ">"; | ||||||||
| 4121 | } | ||||||||
| 4122 | }; | ||||||||
| 4123 | |||||||||
| 4124 | /// Dereferenceable attribute for a floating value. | ||||||||
| 4125 | struct AADereferenceableFloating : AADereferenceableImpl { | ||||||||
| 4126 | AADereferenceableFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 4127 | : AADereferenceableImpl(IRP, A) {} | ||||||||
| 4128 | |||||||||
| 4129 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 4130 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 4131 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 4132 | |||||||||
| 4133 | auto VisitValueCB = [&](const Value &V, const Instruction *, DerefState &T, | ||||||||
| 4134 | bool Stripped) -> bool { | ||||||||
| 4135 | unsigned IdxWidth = | ||||||||
| 4136 | DL.getIndexSizeInBits(V.getType()->getPointerAddressSpace()); | ||||||||
| 4137 | APInt Offset(IdxWidth, 0); | ||||||||
| 4138 | const Value *Base = | ||||||||
| 4139 | stripAndAccumulateMinimalOffsets(A, *this, &V, DL, Offset, false); | ||||||||
| 4140 | |||||||||
| 4141 | const auto &AA = A.getAAFor<AADereferenceable>( | ||||||||
| 4142 | *this, IRPosition::value(*Base), DepClassTy::REQUIRED); | ||||||||
| 4143 | int64_t DerefBytes = 0; | ||||||||
| 4144 | if (!Stripped && this == &AA) { | ||||||||
| 4145 | // Use IR information if we did not strip anything. | ||||||||
| 4146 | // TODO: track globally. | ||||||||
| 4147 | bool CanBeNull, CanBeFreed; | ||||||||
| 4148 | DerefBytes = | ||||||||
| 4149 | Base->getPointerDereferenceableBytes(DL, CanBeNull, CanBeFreed); | ||||||||
| 4150 | T.GlobalState.indicatePessimisticFixpoint(); | ||||||||
| 4151 | } else { | ||||||||
| 4152 | const DerefState &DS = AA.getState(); | ||||||||
| 4153 | DerefBytes = DS.DerefBytesState.getAssumed(); | ||||||||
| 4154 | T.GlobalState &= DS.GlobalState; | ||||||||
| 4155 | } | ||||||||
| 4156 | |||||||||
| 4157 | // For now we do not try to "increase" dereferenceability due to negative | ||||||||
| 4158 | // indices as we first have to come up with code to deal with loops and | ||||||||
| 4159 | // for overflows of the dereferenceable bytes. | ||||||||
| 4160 | int64_t OffsetSExt = Offset.getSExtValue(); | ||||||||
| 4161 | if (OffsetSExt < 0) | ||||||||
| 4162 | OffsetSExt = 0; | ||||||||
| 4163 | |||||||||
| 4164 | T.takeAssumedDerefBytesMinimum( | ||||||||
| 4165 | std::max(int64_t(0), DerefBytes - OffsetSExt)); | ||||||||
| 4166 | |||||||||
| 4167 | if (this == &AA) { | ||||||||
| 4168 | if (!Stripped) { | ||||||||
| 4169 | // If nothing was stripped IR information is all we got. | ||||||||
| 4170 | T.takeKnownDerefBytesMaximum( | ||||||||
| 4171 | std::max(int64_t(0), DerefBytes - OffsetSExt)); | ||||||||
| 4172 | T.indicatePessimisticFixpoint(); | ||||||||
| 4173 | } else if (OffsetSExt > 0) { | ||||||||
| 4174 | // If something was stripped but there is circular reasoning we look | ||||||||
| 4175 | // for the offset. If it is positive we basically decrease the | ||||||||
| 4176 | // dereferenceable bytes in a circluar loop now, which will simply | ||||||||
| 4177 | // drive them down to the known value in a very slow way which we | ||||||||
| 4178 | // can accelerate. | ||||||||
| 4179 | T.indicatePessimisticFixpoint(); | ||||||||
| 4180 | } | ||||||||
| 4181 | } | ||||||||
| 4182 | |||||||||
| 4183 | return T.isValidState(); | ||||||||
| 4184 | }; | ||||||||
| 4185 | |||||||||
| 4186 | DerefState T; | ||||||||
| 4187 | if (!genericValueTraversal<DerefState>(A, getIRPosition(), *this, T, | ||||||||
| 4188 | VisitValueCB, getCtxI())) | ||||||||
| 4189 | return indicatePessimisticFixpoint(); | ||||||||
| 4190 | |||||||||
| 4191 | return clampStateAndIndicateChange(getState(), T); | ||||||||
| 4192 | } | ||||||||
| 4193 | |||||||||
| 4194 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4195 | void trackStatistics() const override { | ||||||||
| 4196 | STATS_DECLTRACK_FLOATING_ATTR(dereferenceable){ static llvm::Statistic NumIRFloating_dereferenceable = {"attributor" , "NumIRFloating_dereferenceable", ("Number of floating values known to be '" "dereferenceable" "'")};; ++(NumIRFloating_dereferenceable); } | ||||||||
| 4197 | } | ||||||||
| 4198 | }; | ||||||||
| 4199 | |||||||||
| 4200 | /// Dereferenceable attribute for a return value. | ||||||||
| 4201 | struct AADereferenceableReturned final | ||||||||
| 4202 | : AAReturnedFromReturnedValues<AADereferenceable, AADereferenceableImpl> { | ||||||||
| 4203 | AADereferenceableReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 4204 | : AAReturnedFromReturnedValues<AADereferenceable, AADereferenceableImpl>( | ||||||||
| 4205 | IRP, A) {} | ||||||||
| 4206 | |||||||||
| 4207 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4208 | void trackStatistics() const override { | ||||||||
| 4209 | STATS_DECLTRACK_FNRET_ATTR(dereferenceable){ static llvm::Statistic NumIRFunctionReturn_dereferenceable = {"attributor", "NumIRFunctionReturn_dereferenceable", ("Number of " "function returns" " marked '" "dereferenceable" "'")};; ++( NumIRFunctionReturn_dereferenceable); } | ||||||||
| 4210 | } | ||||||||
| 4211 | }; | ||||||||
| 4212 | |||||||||
| 4213 | /// Dereferenceable attribute for an argument | ||||||||
| 4214 | struct AADereferenceableArgument final | ||||||||
| 4215 | : AAArgumentFromCallSiteArguments<AADereferenceable, | ||||||||
| 4216 | AADereferenceableImpl> { | ||||||||
| 4217 | using Base = | ||||||||
| 4218 | AAArgumentFromCallSiteArguments<AADereferenceable, AADereferenceableImpl>; | ||||||||
| 4219 | AADereferenceableArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 4220 | : Base(IRP, A) {} | ||||||||
| 4221 | |||||||||
| 4222 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4223 | void trackStatistics() const override { | ||||||||
| 4224 | STATS_DECLTRACK_ARG_ATTR(dereferenceable){ static llvm::Statistic NumIRArguments_dereferenceable = {"attributor" , "NumIRArguments_dereferenceable", ("Number of " "arguments" " marked '" "dereferenceable" "'")};; ++(NumIRArguments_dereferenceable ); } | ||||||||
| 4225 | } | ||||||||
| 4226 | }; | ||||||||
| 4227 | |||||||||
| 4228 | /// Dereferenceable attribute for a call site argument. | ||||||||
| 4229 | struct AADereferenceableCallSiteArgument final : AADereferenceableFloating { | ||||||||
| 4230 | AADereferenceableCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 4231 | : AADereferenceableFloating(IRP, A) {} | ||||||||
| 4232 | |||||||||
| 4233 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4234 | void trackStatistics() const override { | ||||||||
| 4235 | STATS_DECLTRACK_CSARG_ATTR(dereferenceable){ static llvm::Statistic NumIRCSArguments_dereferenceable = { "attributor", "NumIRCSArguments_dereferenceable", ("Number of " "call site arguments" " marked '" "dereferenceable" "'")};; ++ (NumIRCSArguments_dereferenceable); } | ||||||||
| 4236 | } | ||||||||
| 4237 | }; | ||||||||
| 4238 | |||||||||
| 4239 | /// Dereferenceable attribute deduction for a call site return value. | ||||||||
| 4240 | struct AADereferenceableCallSiteReturned final | ||||||||
| 4241 | : AACallSiteReturnedFromReturned<AADereferenceable, AADereferenceableImpl> { | ||||||||
| 4242 | using Base = | ||||||||
| 4243 | AACallSiteReturnedFromReturned<AADereferenceable, AADereferenceableImpl>; | ||||||||
| 4244 | AADereferenceableCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 4245 | : Base(IRP, A) {} | ||||||||
| 4246 | |||||||||
| 4247 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4248 | void trackStatistics() const override { | ||||||||
| 4249 | STATS_DECLTRACK_CS_ATTR(dereferenceable){ static llvm::Statistic NumIRCS_dereferenceable = {"attributor" , "NumIRCS_dereferenceable", ("Number of " "call site" " marked '" "dereferenceable" "'")};; ++(NumIRCS_dereferenceable); }; | ||||||||
| 4250 | } | ||||||||
| 4251 | }; | ||||||||
| 4252 | |||||||||
| 4253 | // ------------------------ Align Argument Attribute ------------------------ | ||||||||
| 4254 | |||||||||
| 4255 | static unsigned getKnownAlignForUse(Attributor &A, AAAlign &QueryingAA, | ||||||||
| 4256 | Value &AssociatedValue, const Use *U, | ||||||||
| 4257 | const Instruction *I, bool &TrackUse) { | ||||||||
| 4258 | // We need to follow common pointer manipulation uses to the accesses they | ||||||||
| 4259 | // feed into. | ||||||||
| 4260 | if (isa<CastInst>(I)) { | ||||||||
| |||||||||
| 4261 | // Follow all but ptr2int casts. | ||||||||
| 4262 | TrackUse = !isa<PtrToIntInst>(I); | ||||||||
| 4263 | return 0; | ||||||||
| 4264 | } | ||||||||
| 4265 | if (auto *GEP
| ||||||||
| 4266 | if (GEP->hasAllConstantIndices()) | ||||||||
| 4267 | TrackUse = true; | ||||||||
| 4268 | return 0; | ||||||||
| 4269 | } | ||||||||
| 4270 | |||||||||
| 4271 | MaybeAlign MA; | ||||||||
| 4272 | if (const auto *CB
| ||||||||
| 4273 | if (CB->isBundleOperand(U) || CB->isCallee(U)) | ||||||||
| 4274 | return 0; | ||||||||
| 4275 | |||||||||
| 4276 | unsigned ArgNo = CB->getArgOperandNo(U); | ||||||||
| 4277 | IRPosition IRP = IRPosition::callsite_argument(*CB, ArgNo); | ||||||||
| 4278 | // As long as we only use known information there is no need to track | ||||||||
| 4279 | // dependences here. | ||||||||
| 4280 | auto &AlignAA = A.getAAFor<AAAlign>(QueryingAA, IRP, DepClassTy::NONE); | ||||||||
| 4281 | MA = MaybeAlign(AlignAA.getKnownAlign()); | ||||||||
| 4282 | } | ||||||||
| 4283 | |||||||||
| 4284 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 4285 | const Value *UseV = U->get(); | ||||||||
| 4286 | if (auto *SI
| ||||||||
| 4287 | if (SI->getPointerOperand() == UseV) | ||||||||
| 4288 | MA = SI->getAlign(); | ||||||||
| 4289 | } else if (auto *LI = dyn_cast<LoadInst>(I)) { | ||||||||
| 4290 | if (LI->getPointerOperand() == UseV) | ||||||||
| 4291 | MA = LI->getAlign(); | ||||||||
| 4292 | } | ||||||||
| 4293 | |||||||||
| 4294 | if (!MA || *MA <= QueryingAA.getKnownAlign()) | ||||||||
| 4295 | return 0; | ||||||||
| 4296 | |||||||||
| 4297 | unsigned Alignment = MA->value(); | ||||||||
| 4298 | int64_t Offset; | ||||||||
| 4299 | |||||||||
| 4300 | if (const Value *Base = GetPointerBaseWithConstantOffset(UseV, Offset, DL)) { | ||||||||
| 4301 | if (Base == &AssociatedValue) { | ||||||||
| 4302 | // BasePointerAddr + Offset = Alignment * Q for some integer Q. | ||||||||
| 4303 | // So we can say that the maximum power of two which is a divisor of | ||||||||
| 4304 | // gcd(Offset, Alignment) is an alignment. | ||||||||
| 4305 | |||||||||
| 4306 | uint32_t gcd = | ||||||||
| 4307 | greatestCommonDivisor(uint32_t(abs((int32_t)Offset)), Alignment); | ||||||||
| 4308 | Alignment = llvm::PowerOf2Floor(gcd); | ||||||||
| 4309 | } | ||||||||
| 4310 | } | ||||||||
| 4311 | |||||||||
| 4312 | return Alignment; | ||||||||
| 4313 | } | ||||||||
| 4314 | |||||||||
| 4315 | struct AAAlignImpl : AAAlign { | ||||||||
| 4316 | AAAlignImpl(const IRPosition &IRP, Attributor &A) : AAAlign(IRP, A) {} | ||||||||
| 4317 | |||||||||
| 4318 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4319 | void initialize(Attributor &A) override { | ||||||||
| 4320 | SmallVector<Attribute, 4> Attrs; | ||||||||
| 4321 | getAttrs({Attribute::Alignment}, Attrs); | ||||||||
| 4322 | for (const Attribute &Attr : Attrs) | ||||||||
| 4323 | takeKnownMaximum(Attr.getValueAsInt()); | ||||||||
| 4324 | |||||||||
| 4325 | Value &V = getAssociatedValue(); | ||||||||
| 4326 | // TODO: This is a HACK to avoid getPointerAlignment to introduce a ptr2int | ||||||||
| 4327 | // use of the function pointer. This was caused by D73131. We want to | ||||||||
| 4328 | // avoid this for function pointers especially because we iterate | ||||||||
| 4329 | // their uses and int2ptr is not handled. It is not a correctness | ||||||||
| 4330 | // problem though! | ||||||||
| 4331 | if (!V.getType()->getPointerElementType()->isFunctionTy()) | ||||||||
| 4332 | takeKnownMaximum(V.getPointerAlignment(A.getDataLayout()).value()); | ||||||||
| 4333 | |||||||||
| 4334 | if (getIRPosition().isFnInterfaceKind() && | ||||||||
| 4335 | (!getAnchorScope() || | ||||||||
| 4336 | !A.isFunctionIPOAmendable(*getAssociatedFunction()))) { | ||||||||
| 4337 | indicatePessimisticFixpoint(); | ||||||||
| 4338 | return; | ||||||||
| 4339 | } | ||||||||
| 4340 | |||||||||
| 4341 | if (Instruction *CtxI = getCtxI()) | ||||||||
| 4342 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||||||
| 4343 | } | ||||||||
| 4344 | |||||||||
| 4345 | /// See AbstractAttribute::manifest(...). | ||||||||
| 4346 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 4347 | ChangeStatus LoadStoreChanged = ChangeStatus::UNCHANGED; | ||||||||
| 4348 | |||||||||
| 4349 | // Check for users that allow alignment annotations. | ||||||||
| 4350 | Value &AssociatedValue = getAssociatedValue(); | ||||||||
| 4351 | for (const Use &U : AssociatedValue.uses()) { | ||||||||
| 4352 | if (auto *SI = dyn_cast<StoreInst>(U.getUser())) { | ||||||||
| 4353 | if (SI->getPointerOperand() == &AssociatedValue) | ||||||||
| 4354 | if (SI->getAlignment() < getAssumedAlign()) { | ||||||||
| 4355 | STATS_DECLTRACK(AAAlign, Store,{ static llvm::Statistic NumIRStore_AAAlign = {"attributor", "NumIRStore_AAAlign" , "Number of times alignment added to a store"};; ++(NumIRStore_AAAlign ); } | ||||||||
| 4356 | "Number of times alignment added to a store"){ static llvm::Statistic NumIRStore_AAAlign = {"attributor", "NumIRStore_AAAlign" , "Number of times alignment added to a store"};; ++(NumIRStore_AAAlign ); }; | ||||||||
| 4357 | SI->setAlignment(Align(getAssumedAlign())); | ||||||||
| 4358 | LoadStoreChanged = ChangeStatus::CHANGED; | ||||||||
| 4359 | } | ||||||||
| 4360 | } else if (auto *LI = dyn_cast<LoadInst>(U.getUser())) { | ||||||||
| 4361 | if (LI->getPointerOperand() == &AssociatedValue) | ||||||||
| 4362 | if (LI->getAlignment() < getAssumedAlign()) { | ||||||||
| 4363 | LI->setAlignment(Align(getAssumedAlign())); | ||||||||
| 4364 | STATS_DECLTRACK(AAAlign, Load,{ static llvm::Statistic NumIRLoad_AAAlign = {"attributor", "NumIRLoad_AAAlign" , "Number of times alignment added to a load"};; ++(NumIRLoad_AAAlign ); } | ||||||||
| 4365 | "Number of times alignment added to a load"){ static llvm::Statistic NumIRLoad_AAAlign = {"attributor", "NumIRLoad_AAAlign" , "Number of times alignment added to a load"};; ++(NumIRLoad_AAAlign ); }; | ||||||||
| 4366 | LoadStoreChanged = ChangeStatus::CHANGED; | ||||||||
| 4367 | } | ||||||||
| 4368 | } | ||||||||
| 4369 | } | ||||||||
| 4370 | |||||||||
| 4371 | ChangeStatus Changed = AAAlign::manifest(A); | ||||||||
| 4372 | |||||||||
| 4373 | Align InheritAlign = | ||||||||
| 4374 | getAssociatedValue().getPointerAlignment(A.getDataLayout()); | ||||||||
| 4375 | if (InheritAlign >= getAssumedAlign()) | ||||||||
| 4376 | return LoadStoreChanged; | ||||||||
| 4377 | return Changed | LoadStoreChanged; | ||||||||
| 4378 | } | ||||||||
| 4379 | |||||||||
| 4380 | // TODO: Provide a helper to determine the implied ABI alignment and check in | ||||||||
| 4381 | // the existing manifest method and a new one for AAAlignImpl that value | ||||||||
| 4382 | // to avoid making the alignment explicit if it did not improve. | ||||||||
| 4383 | |||||||||
| 4384 | /// See AbstractAttribute::getDeducedAttributes | ||||||||
| 4385 | virtual void | ||||||||
| 4386 | getDeducedAttributes(LLVMContext &Ctx, | ||||||||
| 4387 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||||||
| 4388 | if (getAssumedAlign() > 1) | ||||||||
| 4389 | Attrs.emplace_back( | ||||||||
| 4390 | Attribute::getWithAlignment(Ctx, Align(getAssumedAlign()))); | ||||||||
| 4391 | } | ||||||||
| 4392 | |||||||||
| 4393 | /// See followUsesInMBEC | ||||||||
| 4394 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||||||
| 4395 | AAAlign::StateType &State) { | ||||||||
| 4396 | bool TrackUse = false; | ||||||||
| 4397 | |||||||||
| 4398 | unsigned int KnownAlign = | ||||||||
| 4399 | getKnownAlignForUse(A, *this, getAssociatedValue(), U, I, TrackUse); | ||||||||
| 4400 | State.takeKnownMaximum(KnownAlign); | ||||||||
| 4401 | |||||||||
| 4402 | return TrackUse; | ||||||||
| 4403 | } | ||||||||
| 4404 | |||||||||
| 4405 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 4406 | const std::string getAsStr() const override { | ||||||||
| 4407 | return getAssumedAlign() ? ("align<" + std::to_string(getKnownAlign()) + | ||||||||
| 4408 | "-" + std::to_string(getAssumedAlign()) + ">") | ||||||||
| 4409 | : "unknown-align"; | ||||||||
| 4410 | } | ||||||||
| 4411 | }; | ||||||||
| 4412 | |||||||||
| 4413 | /// Align attribute for a floating value. | ||||||||
| 4414 | struct AAAlignFloating : AAAlignImpl { | ||||||||
| 4415 | AAAlignFloating(const IRPosition &IRP, Attributor &A) : AAAlignImpl(IRP, A) {} | ||||||||
| 4416 | |||||||||
| 4417 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 4418 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 4419 | const DataLayout &DL = A.getDataLayout(); | ||||||||
| 4420 | |||||||||
| 4421 | auto VisitValueCB = [&](Value &V, const Instruction *, | ||||||||
| 4422 | AAAlign::StateType &T, bool Stripped) -> bool { | ||||||||
| 4423 | const auto &AA = A.getAAFor<AAAlign>(*this, IRPosition::value(V), | ||||||||
| 4424 | DepClassTy::REQUIRED); | ||||||||
| 4425 | if (!Stripped && this == &AA) { | ||||||||
| 4426 | int64_t Offset; | ||||||||
| 4427 | unsigned Alignment = 1; | ||||||||
| 4428 | if (const Value *Base = | ||||||||
| 4429 | GetPointerBaseWithConstantOffset(&V, Offset, DL)) { | ||||||||
| 4430 | Align PA = Base->getPointerAlignment(DL); | ||||||||
| 4431 | // BasePointerAddr + Offset = Alignment * Q for some integer Q. | ||||||||
| 4432 | // So we can say that the maximum power of two which is a divisor of | ||||||||
| 4433 | // gcd(Offset, Alignment) is an alignment. | ||||||||
| 4434 | |||||||||
| 4435 | uint32_t gcd = greatestCommonDivisor(uint32_t(abs((int32_t)Offset)), | ||||||||
| 4436 | uint32_t(PA.value())); | ||||||||
| 4437 | Alignment = llvm::PowerOf2Floor(gcd); | ||||||||
| 4438 | } else { | ||||||||
| 4439 | Alignment = V.getPointerAlignment(DL).value(); | ||||||||
| 4440 | } | ||||||||
| 4441 | // Use only IR information if we did not strip anything. | ||||||||
| 4442 | T.takeKnownMaximum(Alignment); | ||||||||
| 4443 | T.indicatePessimisticFixpoint(); | ||||||||
| 4444 | } else { | ||||||||
| 4445 | // Use abstract attribute information. | ||||||||
| 4446 | const AAAlign::StateType &DS = AA.getState(); | ||||||||
| 4447 | T ^= DS; | ||||||||
| 4448 | } | ||||||||
| 4449 | return T.isValidState(); | ||||||||
| 4450 | }; | ||||||||
| 4451 | |||||||||
| 4452 | StateType T; | ||||||||
| 4453 | if (!genericValueTraversal<StateType>(A, getIRPosition(), *this, T, | ||||||||
| 4454 | VisitValueCB, getCtxI())) | ||||||||
| 4455 | return indicatePessimisticFixpoint(); | ||||||||
| 4456 | |||||||||
| 4457 | // TODO: If we know we visited all incoming values, thus no are assumed | ||||||||
| 4458 | // dead, we can take the known information from the state T. | ||||||||
| 4459 | return clampStateAndIndicateChange(getState(), T); | ||||||||
| 4460 | } | ||||||||
| 4461 | |||||||||
| 4462 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4463 | void trackStatistics() const override { STATS_DECLTRACK_FLOATING_ATTR(align){ static llvm::Statistic NumIRFloating_align = {"attributor", "NumIRFloating_align", ("Number of floating values known to be '" "align" "'")};; ++(NumIRFloating_align); } } | ||||||||
| 4464 | }; | ||||||||
| 4465 | |||||||||
| 4466 | /// Align attribute for function return value. | ||||||||
| 4467 | struct AAAlignReturned final | ||||||||
| 4468 | : AAReturnedFromReturnedValues<AAAlign, AAAlignImpl> { | ||||||||
| 4469 | using Base = AAReturnedFromReturnedValues<AAAlign, AAAlignImpl>; | ||||||||
| 4470 | AAAlignReturned(const IRPosition &IRP, Attributor &A) : Base(IRP, A) {} | ||||||||
| 4471 | |||||||||
| 4472 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4473 | void initialize(Attributor &A) override { | ||||||||
| 4474 | Base::initialize(A); | ||||||||
| 4475 | Function *F = getAssociatedFunction(); | ||||||||
| 4476 | if (!F || F->isDeclaration()) | ||||||||
| 4477 | indicatePessimisticFixpoint(); | ||||||||
| 4478 | } | ||||||||
| 4479 | |||||||||
| 4480 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4481 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(aligned){ static llvm::Statistic NumIRFunctionReturn_aligned = {"attributor" , "NumIRFunctionReturn_aligned", ("Number of " "function returns" " marked '" "aligned" "'")};; ++(NumIRFunctionReturn_aligned ); } } | ||||||||
| 4482 | }; | ||||||||
| 4483 | |||||||||
| 4484 | /// Align attribute for function argument. | ||||||||
| 4485 | struct AAAlignArgument final | ||||||||
| 4486 | : AAArgumentFromCallSiteArguments<AAAlign, AAAlignImpl> { | ||||||||
| 4487 | using Base = AAArgumentFromCallSiteArguments<AAAlign, AAAlignImpl>; | ||||||||
| 4488 | AAAlignArgument(const IRPosition &IRP, Attributor &A) : Base(IRP, A) {} | ||||||||
| 4489 | |||||||||
| 4490 | /// See AbstractAttribute::manifest(...). | ||||||||
| 4491 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 4492 | // If the associated argument is involved in a must-tail call we give up | ||||||||
| 4493 | // because we would need to keep the argument alignments of caller and | ||||||||
| 4494 | // callee in-sync. Just does not seem worth the trouble right now. | ||||||||
| 4495 | if (A.getInfoCache().isInvolvedInMustTailCall(*getAssociatedArgument())) | ||||||||
| 4496 | return ChangeStatus::UNCHANGED; | ||||||||
| 4497 | return Base::manifest(A); | ||||||||
| 4498 | } | ||||||||
| 4499 | |||||||||
| 4500 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4501 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(aligned){ static llvm::Statistic NumIRArguments_aligned = {"attributor" , "NumIRArguments_aligned", ("Number of " "arguments" " marked '" "aligned" "'")};; ++(NumIRArguments_aligned); } } | ||||||||
| 4502 | }; | ||||||||
| 4503 | |||||||||
| 4504 | struct AAAlignCallSiteArgument final : AAAlignFloating { | ||||||||
| 4505 | AAAlignCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 4506 | : AAAlignFloating(IRP, A) {} | ||||||||
| 4507 | |||||||||
| 4508 | /// See AbstractAttribute::manifest(...). | ||||||||
| 4509 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 4510 | // If the associated argument is involved in a must-tail call we give up | ||||||||
| 4511 | // because we would need to keep the argument alignments of caller and | ||||||||
| 4512 | // callee in-sync. Just does not seem worth the trouble right now. | ||||||||
| 4513 | if (Argument *Arg = getAssociatedArgument()) | ||||||||
| 4514 | if (A.getInfoCache().isInvolvedInMustTailCall(*Arg)) | ||||||||
| 4515 | return ChangeStatus::UNCHANGED; | ||||||||
| 4516 | ChangeStatus Changed = AAAlignImpl::manifest(A); | ||||||||
| 4517 | Align InheritAlign = | ||||||||
| 4518 | getAssociatedValue().getPointerAlignment(A.getDataLayout()); | ||||||||
| 4519 | if (InheritAlign >= getAssumedAlign()) | ||||||||
| 4520 | Changed = ChangeStatus::UNCHANGED; | ||||||||
| 4521 | return Changed; | ||||||||
| 4522 | } | ||||||||
| 4523 | |||||||||
| 4524 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||||||
| 4525 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 4526 | ChangeStatus Changed = AAAlignFloating::updateImpl(A); | ||||||||
| 4527 | if (Argument *Arg = getAssociatedArgument()) { | ||||||||
| 4528 | // We only take known information from the argument | ||||||||
| 4529 | // so we do not need to track a dependence. | ||||||||
| 4530 | const auto &ArgAlignAA = A.getAAFor<AAAlign>( | ||||||||
| 4531 | *this, IRPosition::argument(*Arg), DepClassTy::NONE); | ||||||||
| 4532 | takeKnownMaximum(ArgAlignAA.getKnownAlign()); | ||||||||
| 4533 | } | ||||||||
| 4534 | return Changed; | ||||||||
| 4535 | } | ||||||||
| 4536 | |||||||||
| 4537 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4538 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(aligned){ static llvm::Statistic NumIRCSArguments_aligned = {"attributor" , "NumIRCSArguments_aligned", ("Number of " "call site arguments" " marked '" "aligned" "'")};; ++(NumIRCSArguments_aligned); } } | ||||||||
| 4539 | }; | ||||||||
| 4540 | |||||||||
| 4541 | /// Align attribute deduction for a call site return value. | ||||||||
| 4542 | struct AAAlignCallSiteReturned final | ||||||||
| 4543 | : AACallSiteReturnedFromReturned<AAAlign, AAAlignImpl> { | ||||||||
| 4544 | using Base = AACallSiteReturnedFromReturned<AAAlign, AAAlignImpl>; | ||||||||
| 4545 | AAAlignCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 4546 | : Base(IRP, A) {} | ||||||||
| 4547 | |||||||||
| 4548 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4549 | void initialize(Attributor &A) override { | ||||||||
| 4550 | Base::initialize(A); | ||||||||
| 4551 | Function *F = getAssociatedFunction(); | ||||||||
| 4552 | if (!F || F->isDeclaration()) | ||||||||
| 4553 | indicatePessimisticFixpoint(); | ||||||||
| 4554 | } | ||||||||
| 4555 | |||||||||
| 4556 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4557 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(align){ static llvm::Statistic NumIRCS_align = {"attributor", "NumIRCS_align" , ("Number of " "call site" " marked '" "align" "'")};; ++(NumIRCS_align ); }; } | ||||||||
| 4558 | }; | ||||||||
| 4559 | |||||||||
| 4560 | /// ------------------ Function No-Return Attribute ---------------------------- | ||||||||
| 4561 | struct AANoReturnImpl : public AANoReturn { | ||||||||
| 4562 | AANoReturnImpl(const IRPosition &IRP, Attributor &A) : AANoReturn(IRP, A) {} | ||||||||
| 4563 | |||||||||
| 4564 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4565 | void initialize(Attributor &A) override { | ||||||||
| 4566 | AANoReturn::initialize(A); | ||||||||
| 4567 | Function *F = getAssociatedFunction(); | ||||||||
| 4568 | if (!F || F->isDeclaration()) | ||||||||
| 4569 | indicatePessimisticFixpoint(); | ||||||||
| 4570 | } | ||||||||
| 4571 | |||||||||
| 4572 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 4573 | const std::string getAsStr() const override { | ||||||||
| 4574 | return getAssumed() ? "noreturn" : "may-return"; | ||||||||
| 4575 | } | ||||||||
| 4576 | |||||||||
| 4577 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||||||
| 4578 | virtual ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 4579 | auto CheckForNoReturn = [](Instruction &) { return false; }; | ||||||||
| 4580 | bool UsedAssumedInformation = false; | ||||||||
| 4581 | if (!A.checkForAllInstructions(CheckForNoReturn, *this, | ||||||||
| 4582 | {(unsigned)Instruction::Ret}, | ||||||||
| 4583 | UsedAssumedInformation)) | ||||||||
| 4584 | return indicatePessimisticFixpoint(); | ||||||||
| 4585 | return ChangeStatus::UNCHANGED; | ||||||||
| 4586 | } | ||||||||
| 4587 | }; | ||||||||
| 4588 | |||||||||
| 4589 | struct AANoReturnFunction final : AANoReturnImpl { | ||||||||
| 4590 | AANoReturnFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 4591 | : AANoReturnImpl(IRP, A) {} | ||||||||
| 4592 | |||||||||
| 4593 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4594 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(noreturn){ static llvm::Statistic NumIRFunction_noreturn = {"attributor" , "NumIRFunction_noreturn", ("Number of " "functions" " marked '" "noreturn" "'")};; ++(NumIRFunction_noreturn); } } | ||||||||
| 4595 | }; | ||||||||
| 4596 | |||||||||
| 4597 | /// NoReturn attribute deduction for a call sites. | ||||||||
| 4598 | struct AANoReturnCallSite final : AANoReturnImpl { | ||||||||
| 4599 | AANoReturnCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 4600 | : AANoReturnImpl(IRP, A) {} | ||||||||
| 4601 | |||||||||
| 4602 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4603 | void initialize(Attributor &A) override { | ||||||||
| 4604 | AANoReturnImpl::initialize(A); | ||||||||
| 4605 | if (Function *F = getAssociatedFunction()) { | ||||||||
| 4606 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 4607 | auto &FnAA = A.getAAFor<AANoReturn>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 4608 | if (!FnAA.isAssumedNoReturn()) | ||||||||
| 4609 | indicatePessimisticFixpoint(); | ||||||||
| 4610 | } | ||||||||
| 4611 | } | ||||||||
| 4612 | |||||||||
| 4613 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 4614 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 4615 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 4616 | // call site specific liveness information and then it makes | ||||||||
| 4617 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 4618 | // redirecting requests to the callee argument. | ||||||||
| 4619 | Function *F = getAssociatedFunction(); | ||||||||
| 4620 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 4621 | auto &FnAA = A.getAAFor<AANoReturn>(*this, FnPos, DepClassTy::REQUIRED); | ||||||||
| 4622 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||||||
| 4623 | } | ||||||||
| 4624 | |||||||||
| 4625 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 4626 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(noreturn){ static llvm::Statistic NumIRCS_noreturn = {"attributor", "NumIRCS_noreturn" , ("Number of " "call site" " marked '" "noreturn" "'")};; ++ (NumIRCS_noreturn); }; } | ||||||||
| 4627 | }; | ||||||||
| 4628 | |||||||||
| 4629 | /// ----------------------- Variable Capturing --------------------------------- | ||||||||
| 4630 | |||||||||
| 4631 | /// A class to hold the state of for no-capture attributes. | ||||||||
| 4632 | struct AANoCaptureImpl : public AANoCapture { | ||||||||
| 4633 | AANoCaptureImpl(const IRPosition &IRP, Attributor &A) : AANoCapture(IRP, A) {} | ||||||||
| 4634 | |||||||||
| 4635 | /// See AbstractAttribute::initialize(...). | ||||||||
| 4636 | void initialize(Attributor &A) override { | ||||||||
| 4637 | if (hasAttr(getAttrKind(), /* IgnoreSubsumingPositions */ true)) { | ||||||||
| 4638 | indicateOptimisticFixpoint(); | ||||||||
| 4639 | return; | ||||||||
| 4640 | } | ||||||||
| 4641 | Function *AnchorScope = getAnchorScope(); | ||||||||
| 4642 | if (isFnInterfaceKind() && | ||||||||
| 4643 | (!AnchorScope || !A.isFunctionIPOAmendable(*AnchorScope))) { | ||||||||
| 4644 | indicatePessimisticFixpoint(); | ||||||||
| 4645 | return; | ||||||||
| 4646 | } | ||||||||
| 4647 | |||||||||
| 4648 | // You cannot "capture" null in the default address space. | ||||||||
| 4649 | if (isa<ConstantPointerNull>(getAssociatedValue()) && | ||||||||
| 4650 | getAssociatedValue().getType()->getPointerAddressSpace() == 0) { | ||||||||
| 4651 | indicateOptimisticFixpoint(); | ||||||||
| 4652 | return; | ||||||||
| 4653 | } | ||||||||
| 4654 | |||||||||
| 4655 | const Function *F = | ||||||||
| 4656 | isArgumentPosition() ? getAssociatedFunction() : AnchorScope; | ||||||||
| 4657 | |||||||||
| 4658 | // Check what state the associated function can actually capture. | ||||||||
| 4659 | if (F) | ||||||||
| 4660 | determineFunctionCaptureCapabilities(getIRPosition(), *F, *this); | ||||||||
| 4661 | else | ||||||||
| 4662 | indicatePessimisticFixpoint(); | ||||||||
| 4663 | } | ||||||||
| 4664 | |||||||||
| 4665 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 4666 | ChangeStatus updateImpl(Attributor &A) override; | ||||||||
| 4667 | |||||||||
| 4668 | /// see AbstractAttribute::isAssumedNoCaptureMaybeReturned(...). | ||||||||
| 4669 | virtual void | ||||||||
| 4670 | getDeducedAttributes(LLVMContext &Ctx, | ||||||||
| 4671 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||||||
| 4672 | if (!isAssumedNoCaptureMaybeReturned()) | ||||||||
| 4673 | return; | ||||||||
| 4674 | |||||||||
| 4675 | if (isArgumentPosition()) { | ||||||||
| 4676 | if (isAssumedNoCapture()) | ||||||||
| 4677 | Attrs.emplace_back(Attribute::get(Ctx, Attribute::NoCapture)); | ||||||||
| 4678 | else if (ManifestInternal) | ||||||||
| 4679 | Attrs.emplace_back(Attribute::get(Ctx, "no-capture-maybe-returned")); | ||||||||
| 4680 | } | ||||||||
| 4681 | } | ||||||||
| 4682 | |||||||||
| 4683 | /// Set the NOT_CAPTURED_IN_MEM and NOT_CAPTURED_IN_RET bits in \p Known | ||||||||
| 4684 | /// depending on the ability of the function associated with \p IRP to capture | ||||||||
| 4685 | /// state in memory and through "returning/throwing", respectively. | ||||||||
| 4686 | static void determineFunctionCaptureCapabilities(const IRPosition &IRP, | ||||||||
| 4687 | const Function &F, | ||||||||
| 4688 | BitIntegerState &State) { | ||||||||
| 4689 | // TODO: Once we have memory behavior attributes we should use them here. | ||||||||
| 4690 | |||||||||
| 4691 | // If we know we cannot communicate or write to memory, we do not care about | ||||||||
| 4692 | // ptr2int anymore. | ||||||||
| 4693 | if (F.onlyReadsMemory() && F.doesNotThrow() && | ||||||||
| 4694 | F.getReturnType()->isVoidTy()) { | ||||||||
| 4695 | State.addKnownBits(NO_CAPTURE); | ||||||||
| 4696 | return; | ||||||||
| 4697 | } | ||||||||
| 4698 | |||||||||
| 4699 | // A function cannot capture state in memory if it only reads memory, it can | ||||||||
| 4700 | // however return/throw state and the state might be influenced by the | ||||||||
| 4701 | // pointer value, e.g., loading from a returned pointer might reveal a bit. | ||||||||
| 4702 | if (F.onlyReadsMemory()) | ||||||||
| 4703 | State.addKnownBits(NOT_CAPTURED_IN_MEM); | ||||||||
| 4704 | |||||||||
| 4705 | // A function cannot communicate state back if it does not through | ||||||||
| 4706 | // exceptions and doesn not return values. | ||||||||
| 4707 | if (F.doesNotThrow() && F.getReturnType()->isVoidTy()) | ||||||||
| 4708 | State.addKnownBits(NOT_CAPTURED_IN_RET); | ||||||||
| 4709 | |||||||||
| 4710 | // Check existing "returned" attributes. | ||||||||
| 4711 | int ArgNo = IRP.getCalleeArgNo(); | ||||||||
| 4712 | if (F.doesNotThrow() && ArgNo >= 0) { | ||||||||
| 4713 | for (unsigned u = 0, e = F.arg_size(); u < e; ++u) | ||||||||
| 4714 | if (F.hasParamAttribute(u, Attribute::Returned)) { | ||||||||
| 4715 | if (u == unsigned(ArgNo)) | ||||||||
| 4716 | State.removeAssumedBits(NOT_CAPTURED_IN_RET); | ||||||||
| 4717 | else if (F.onlyReadsMemory()) | ||||||||
| 4718 | State.addKnownBits(NO_CAPTURE); | ||||||||
| 4719 | else | ||||||||
| 4720 | State.addKnownBits(NOT_CAPTURED_IN_RET); | ||||||||
| 4721 | break; | ||||||||
| 4722 | } | ||||||||
| 4723 | } | ||||||||
| 4724 | } | ||||||||
| 4725 | |||||||||
| 4726 | /// See AbstractState::getAsStr(). | ||||||||
| 4727 | const std::string getAsStr() const override { | ||||||||
| 4728 | if (isKnownNoCapture()) | ||||||||
| 4729 | return "known not-captured"; | ||||||||
| 4730 | if (isAssumedNoCapture()) | ||||||||
| 4731 | return "assumed not-captured"; | ||||||||
| 4732 | if (isKnownNoCaptureMaybeReturned()) | ||||||||
| 4733 | return "known not-captured-maybe-returned"; | ||||||||
| 4734 | if (isAssumedNoCaptureMaybeReturned()) | ||||||||
| 4735 | return "assumed not-captured-maybe-returned"; | ||||||||
| 4736 | return "assumed-captured"; | ||||||||
| 4737 | } | ||||||||
| 4738 | }; | ||||||||
| 4739 | |||||||||
| 4740 | /// Attributor-aware capture tracker. | ||||||||
| 4741 | struct AACaptureUseTracker final : public CaptureTracker { | ||||||||
| 4742 | |||||||||
| 4743 | /// Create a capture tracker that can lookup in-flight abstract attributes | ||||||||
| 4744 | /// through the Attributor \p A. | ||||||||
| 4745 | /// | ||||||||
| 4746 | /// If a use leads to a potential capture, \p CapturedInMemory is set and the | ||||||||
| 4747 | /// search is stopped. If a use leads to a return instruction, | ||||||||
| 4748 | /// \p CommunicatedBack is set to true and \p CapturedInMemory is not changed. | ||||||||
| 4749 | /// If a use leads to a ptr2int which may capture the value, | ||||||||
| 4750 | /// \p CapturedInInteger is set. If a use is found that is currently assumed | ||||||||
| 4751 | /// "no-capture-maybe-returned", the user is added to the \p PotentialCopies | ||||||||
| 4752 | /// set. All values in \p PotentialCopies are later tracked as well. For every | ||||||||
| 4753 | /// explored use we decrement \p RemainingUsesToExplore. Once it reaches 0, | ||||||||
| 4754 | /// the search is stopped with \p CapturedInMemory and \p CapturedInInteger | ||||||||
| 4755 | /// conservatively set to true. | ||||||||
| 4756 | AACaptureUseTracker(Attributor &A, AANoCapture &NoCaptureAA, | ||||||||
| 4757 | const AAIsDead &IsDeadAA, AANoCapture::StateType &State, | ||||||||
| 4758 | SmallSetVector<Value *, 4> &PotentialCopies, | ||||||||
| 4759 | unsigned &RemainingUsesToExplore) | ||||||||
| 4760 | : A(A), NoCaptureAA(NoCaptureAA), IsDeadAA(IsDeadAA), State(State), | ||||||||
| 4761 | PotentialCopies(PotentialCopies), | ||||||||
| 4762 | RemainingUsesToExplore(RemainingUsesToExplore) {} | ||||||||
| 4763 | |||||||||
| 4764 | /// Determine if \p V maybe captured. *Also updates the state!* | ||||||||
| 4765 | bool valueMayBeCaptured(const Value *V) { | ||||||||
| 4766 | if (V->getType()->isPointerTy()) { | ||||||||
| 4767 | PointerMayBeCaptured(V, this); | ||||||||
| 4768 | } else { | ||||||||
| 4769 | State.indicatePessimisticFixpoint(); | ||||||||
| 4770 | } | ||||||||
| 4771 | return State.isAssumed(AANoCapture::NO_CAPTURE_MAYBE_RETURNED); | ||||||||
| 4772 | } | ||||||||
| 4773 | |||||||||
| 4774 | /// See CaptureTracker::tooManyUses(). | ||||||||
| 4775 | void tooManyUses() override { | ||||||||
| 4776 | State.removeAssumedBits(AANoCapture::NO_CAPTURE); | ||||||||
| 4777 | } | ||||||||
| 4778 | |||||||||
| 4779 | bool isDereferenceableOrNull(Value *O, const DataLayout &DL) override { | ||||||||
| 4780 | if (CaptureTracker::isDereferenceableOrNull(O, DL)) | ||||||||
| 4781 | return true; | ||||||||
| 4782 | const auto &DerefAA = A.getAAFor<AADereferenceable>( | ||||||||
| 4783 | NoCaptureAA, IRPosition::value(*O), DepClassTy::OPTIONAL); | ||||||||
| 4784 | return DerefAA.getAssumedDereferenceableBytes(); | ||||||||
| 4785 | } | ||||||||
| 4786 | |||||||||
| 4787 | /// See CaptureTracker::captured(...). | ||||||||
| 4788 | bool captured(const Use *U) override { | ||||||||
| 4789 | Instruction *UInst = cast<Instruction>(U->getUser()); | ||||||||
| 4790 | LLVM_DEBUG(dbgs() << "Check use: " << *U->get() << " in " << *UInstdo { } while (false) | ||||||||
| 4791 | << "\n")do { } while (false); | ||||||||
| 4792 | |||||||||
| 4793 | // Because we may reuse the tracker multiple times we keep track of the | ||||||||
| 4794 | // number of explored uses ourselves as well. | ||||||||
| 4795 | if (RemainingUsesToExplore-- == 0) { | ||||||||
| 4796 | LLVM_DEBUG(dbgs() << " - too many uses to explore!\n")do { } while (false); | ||||||||
| 4797 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||||||
| 4798 | /* Return */ true); | ||||||||
| 4799 | } | ||||||||
| 4800 | |||||||||
| 4801 | // Deal with ptr2int by following uses. | ||||||||
| 4802 | if (isa<PtrToIntInst>(UInst)) { | ||||||||
| 4803 | LLVM_DEBUG(dbgs() << " - ptr2int assume the worst!\n")do { } while (false); | ||||||||
| 4804 | return valueMayBeCaptured(UInst); | ||||||||
| 4805 | } | ||||||||
| 4806 | |||||||||
| 4807 | // For stores we check if we can follow the value through memory or not. | ||||||||
| 4808 | if (auto *SI = dyn_cast<StoreInst>(UInst)) { | ||||||||
| 4809 | if (SI->isVolatile()) | ||||||||
| 4810 | return isCapturedIn(/* Memory */ true, /* Integer */ false, | ||||||||
| 4811 | /* Return */ false); | ||||||||
| 4812 | bool UsedAssumedInformation = false; | ||||||||
| 4813 | if (!AA::getPotentialCopiesOfStoredValue( | ||||||||
| 4814 | A, *SI, PotentialCopies, NoCaptureAA, UsedAssumedInformation)) | ||||||||
| 4815 | return isCapturedIn(/* Memory */ true, /* Integer */ false, | ||||||||
| 4816 | /* Return */ false); | ||||||||
| 4817 | // Not captured directly, potential copies will be checked. | ||||||||
| 4818 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||||||
| 4819 | /* Return */ false); | ||||||||
| 4820 | } | ||||||||
| 4821 | |||||||||
| 4822 | // Explicitly catch return instructions. | ||||||||
| 4823 | if (isa<ReturnInst>(UInst)) { | ||||||||
| 4824 | if (UInst->getFunction() == NoCaptureAA.getAnchorScope()) | ||||||||
| 4825 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||||||
| 4826 | /* Return */ true); | ||||||||
| 4827 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||||||
| 4828 | /* Return */ true); | ||||||||
| 4829 | } | ||||||||
| 4830 | |||||||||
| 4831 | // For now we only use special logic for call sites. However, the tracker | ||||||||
| 4832 | // itself knows about a lot of other non-capturing cases already. | ||||||||
| 4833 | auto *CB = dyn_cast<CallBase>(UInst); | ||||||||
| 4834 | if (!CB || !CB->isArgOperand(U)) | ||||||||
| 4835 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||||||
| 4836 | /* Return */ true); | ||||||||
| 4837 | |||||||||
| 4838 | unsigned ArgNo = CB->getArgOperandNo(U); | ||||||||
| 4839 | const IRPosition &CSArgPos = IRPosition::callsite_argument(*CB, ArgNo); | ||||||||
| 4840 | // If we have a abstract no-capture attribute for the argument we can use | ||||||||
| 4841 | // it to justify a non-capture attribute here. This allows recursion! | ||||||||
| 4842 | auto &ArgNoCaptureAA = | ||||||||
| 4843 | A.getAAFor<AANoCapture>(NoCaptureAA, CSArgPos, DepClassTy::REQUIRED); | ||||||||
| 4844 | if (ArgNoCaptureAA.isAssumedNoCapture()) | ||||||||
| 4845 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||||||
| 4846 | /* Return */ false); | ||||||||
| 4847 | if (ArgNoCaptureAA.isAssumedNoCaptureMaybeReturned()) { | ||||||||
| 4848 | addPotentialCopy(*CB); | ||||||||
| 4849 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||||||
| 4850 | /* Return */ false); | ||||||||
| 4851 | } | ||||||||
| 4852 | |||||||||
| 4853 | // Lastly, we could not find a reason no-capture can be assumed so we don't. | ||||||||
| 4854 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||||||
| 4855 | /* Return */ true); | ||||||||
| 4856 | } | ||||||||
| 4857 | |||||||||
| 4858 | /// Register \p CS as potential copy of the value we are checking. | ||||||||
| 4859 | void addPotentialCopy(CallBase &CB) { PotentialCopies.insert(&CB); } | ||||||||
| 4860 | |||||||||
| 4861 | /// See CaptureTracker::shouldExplore(...). | ||||||||
| 4862 | bool shouldExplore(const Use *U) override { | ||||||||
| 4863 | // Check liveness and ignore droppable users. | ||||||||
| 4864 | bool UsedAssumedInformation = false; | ||||||||
| 4865 | return !U->getUser()->isDroppable() && | ||||||||
| 4866 | !A.isAssumedDead(*U, &NoCaptureAA, &IsDeadAA, | ||||||||
| 4867 | UsedAssumedInformation); | ||||||||
| 4868 | } | ||||||||
| 4869 | |||||||||
| 4870 | /// Update the state according to \p CapturedInMem, \p CapturedInInt, and | ||||||||
| 4871 | /// \p CapturedInRet, then return the appropriate value for use in the | ||||||||
| 4872 | /// CaptureTracker::captured() interface. | ||||||||
| 4873 | bool isCapturedIn(bool CapturedInMem, bool CapturedInInt, | ||||||||
| 4874 | bool CapturedInRet) { | ||||||||
| 4875 | LLVM_DEBUG(dbgs() << " - captures [Mem " << CapturedInMem << "|Int "do { } while (false) | ||||||||
| 4876 | << CapturedInInt << "|Ret " << CapturedInRet << "]\n")do { } while (false); | ||||||||
| 4877 | if (CapturedInMem) | ||||||||
| 4878 | State.removeAssumedBits(AANoCapture::NOT_CAPTURED_IN_MEM); | ||||||||
| 4879 | if (CapturedInInt) | ||||||||
| 4880 | State.removeAssumedBits(AANoCapture::NOT_CAPTURED_IN_INT); | ||||||||
| 4881 | if (CapturedInRet) | ||||||||
| 4882 | State.removeAssumedBits(AANoCapture::NOT_CAPTURED_IN_RET); | ||||||||
| 4883 | return !State.isAssumed(AANoCapture::NO_CAPTURE_MAYBE_RETURNED); | ||||||||
| 4884 | } | ||||||||
| 4885 | |||||||||
| 4886 | private: | ||||||||
| 4887 | /// The attributor providing in-flight abstract attributes. | ||||||||
| 4888 | Attributor &A; | ||||||||
| 4889 | |||||||||
| 4890 | /// The abstract attribute currently updated. | ||||||||
| 4891 | AANoCapture &NoCaptureAA; | ||||||||
| 4892 | |||||||||
| 4893 | /// The abstract liveness state. | ||||||||
| 4894 | const AAIsDead &IsDeadAA; | ||||||||
| 4895 | |||||||||
| 4896 | /// The state currently updated. | ||||||||
| 4897 | AANoCapture::StateType &State; | ||||||||
| 4898 | |||||||||
| 4899 | /// Set of potential copies of the tracked value. | ||||||||
| 4900 | SmallSetVector<Value *, 4> &PotentialCopies; | ||||||||
| 4901 | |||||||||
| 4902 | /// Global counter to limit the number of explored uses. | ||||||||
| 4903 | unsigned &RemainingUsesToExplore; | ||||||||
| 4904 | }; | ||||||||
| 4905 | |||||||||
| 4906 | ChangeStatus AANoCaptureImpl::updateImpl(Attributor &A) { | ||||||||
| 4907 | const IRPosition &IRP = getIRPosition(); | ||||||||
| 4908 | Value *V = isArgumentPosition() ? IRP.getAssociatedArgument() | ||||||||
| 4909 | : &IRP.getAssociatedValue(); | ||||||||
| 4910 | if (!V) | ||||||||
| 4911 | return indicatePessimisticFixpoint(); | ||||||||
| 4912 | |||||||||
| 4913 | const Function *F = | ||||||||
| 4914 | isArgumentPosition() ? IRP.getAssociatedFunction() : IRP.getAnchorScope(); | ||||||||
| 4915 | assert(F && "Expected a function!")((void)0); | ||||||||
| 4916 | const IRPosition &FnPos = IRPosition::function(*F); | ||||||||
| 4917 | const auto &IsDeadAA = A.getAAFor<AAIsDead>(*this, FnPos, DepClassTy::NONE); | ||||||||
| 4918 | |||||||||
| 4919 | AANoCapture::StateType T; | ||||||||
| 4920 | |||||||||
| 4921 | // Readonly means we cannot capture through memory. | ||||||||
| 4922 | const auto &FnMemAA = | ||||||||
| 4923 | A.getAAFor<AAMemoryBehavior>(*this, FnPos, DepClassTy::NONE); | ||||||||
| 4924 | if (FnMemAA.isAssumedReadOnly()) { | ||||||||
| 4925 | T.addKnownBits(NOT_CAPTURED_IN_MEM); | ||||||||
| 4926 | if (FnMemAA.isKnownReadOnly()) | ||||||||
| 4927 | addKnownBits(NOT_CAPTURED_IN_MEM); | ||||||||
| 4928 | else | ||||||||
| 4929 | A.recordDependence(FnMemAA, *this, DepClassTy::OPTIONAL); | ||||||||
| 4930 | } | ||||||||
| 4931 | |||||||||
| 4932 | // Make sure all returned values are different than the underlying value. | ||||||||
| 4933 | // TODO: we could do this in a more sophisticated way inside | ||||||||
| 4934 | // AAReturnedValues, e.g., track all values that escape through returns | ||||||||
| 4935 | // directly somehow. | ||||||||
| 4936 | auto CheckReturnedArgs = [&](const AAReturnedValues &RVAA) { | ||||||||
| 4937 | bool SeenConstant = false; | ||||||||
| 4938 | for (auto &It : RVAA.returned_values()) { | ||||||||
| 4939 | if (isa<Constant>(It.first)) { | ||||||||
| 4940 | if (SeenConstant) | ||||||||
| 4941 | return false; | ||||||||
| 4942 | SeenConstant = true; | ||||||||
| 4943 | } else if (!isa<Argument>(It.first) || | ||||||||
| 4944 | It.first == getAssociatedArgument()) | ||||||||
| 4945 | return false; | ||||||||
| 4946 | } | ||||||||
| 4947 | return true; | ||||||||
| 4948 | }; | ||||||||
| 4949 | |||||||||
| 4950 | const auto &NoUnwindAA = | ||||||||
| 4951 | A.getAAFor<AANoUnwind>(*this, FnPos, DepClassTy::OPTIONAL); | ||||||||
| 4952 | if (NoUnwindAA.isAssumedNoUnwind()) { | ||||||||
| 4953 | bool IsVoidTy = F->getReturnType()->isVoidTy(); | ||||||||
| 4954 | const AAReturnedValues *RVAA = | ||||||||
| 4955 | IsVoidTy ? nullptr | ||||||||
| 4956 | : &A.getAAFor<AAReturnedValues>(*this, FnPos, | ||||||||
| 4957 | |||||||||
| 4958 | DepClassTy::OPTIONAL); | ||||||||
| 4959 | if (IsVoidTy || CheckReturnedArgs(*RVAA)) { | ||||||||
| 4960 | T.addKnownBits(NOT_CAPTURED_IN_RET); | ||||||||
| 4961 | if (T.isKnown(NOT_CAPTURED_IN_MEM)) | ||||||||
| 4962 | return ChangeStatus::UNCHANGED; | ||||||||
| 4963 | if (NoUnwindAA.isKnownNoUnwind() && | ||||||||
| 4964 | (IsVoidTy || RVAA->getState().isAtFixpoint())) { | ||||||||
| 4965 | addKnownBits(NOT_CAPTURED_IN_RET); | ||||||||
| 4966 | if (isKnown(NOT_CAPTURED_IN_MEM)) | ||||||||
| 4967 | return indicateOptimisticFixpoint(); | ||||||||
| 4968 | } | ||||||||
| 4969 | } | ||||||||
| 4970 | } | ||||||||
| 4971 | |||||||||
| 4972 | // Use the CaptureTracker interface and logic with the specialized tracker, | ||||||||
| 4973 | // defined in AACaptureUseTracker, that can look at in-flight abstract | ||||||||
| 4974 | // attributes and directly updates the assumed state. | ||||||||
| 4975 | SmallSetVector<Value *, 4> PotentialCopies; | ||||||||
| 4976 | unsigned RemainingUsesToExplore = | ||||||||
| 4977 | getDefaultMaxUsesToExploreForCaptureTracking(); | ||||||||
| 4978 | AACaptureUseTracker Tracker(A, *this, IsDeadAA, T, PotentialCopies, | ||||||||
| 4979 | RemainingUsesToExplore); | ||||||||
| 4980 | |||||||||
| 4981 | // Check all potential copies of the associated value until we can assume | ||||||||
| 4982 | // none will be captured or we have to assume at least one might be. | ||||||||
| 4983 | unsigned Idx = 0; | ||||||||
| 4984 | PotentialCopies.insert(V); | ||||||||
| 4985 | while (T.isAssumed(NO_CAPTURE_MAYBE_RETURNED) && Idx < PotentialCopies.size()) | ||||||||
| 4986 | Tracker.valueMayBeCaptured(PotentialCopies[Idx++]); | ||||||||
| 4987 | |||||||||
| 4988 | AANoCapture::StateType &S = getState(); | ||||||||
| 4989 | auto Assumed = S.getAssumed(); | ||||||||
| 4990 | S.intersectAssumedBits(T.getAssumed()); | ||||||||
| 4991 | if (!isAssumedNoCaptureMaybeReturned()) | ||||||||
| 4992 | return indicatePessimisticFixpoint(); | ||||||||
| 4993 | return Assumed == S.getAssumed() ? ChangeStatus::UNCHANGED | ||||||||
| 4994 | : ChangeStatus::CHANGED; | ||||||||
| 4995 | } | ||||||||
| 4996 | |||||||||
| 4997 | /// NoCapture attribute for function arguments. | ||||||||
| 4998 | struct AANoCaptureArgument final : AANoCaptureImpl { | ||||||||
| 4999 | AANoCaptureArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 5000 | : AANoCaptureImpl(IRP, A) {} | ||||||||
| 5001 | |||||||||
| 5002 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5003 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(nocapture){ static llvm::Statistic NumIRArguments_nocapture = {"attributor" , "NumIRArguments_nocapture", ("Number of " "arguments" " marked '" "nocapture" "'")};; ++(NumIRArguments_nocapture); } } | ||||||||
| 5004 | }; | ||||||||
| 5005 | |||||||||
| 5006 | /// NoCapture attribute for call site arguments. | ||||||||
| 5007 | struct AANoCaptureCallSiteArgument final : AANoCaptureImpl { | ||||||||
| 5008 | AANoCaptureCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 5009 | : AANoCaptureImpl(IRP, A) {} | ||||||||
| 5010 | |||||||||
| 5011 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5012 | void initialize(Attributor &A) override { | ||||||||
| 5013 | if (Argument *Arg = getAssociatedArgument()) | ||||||||
| 5014 | if (Arg->hasByValAttr()) | ||||||||
| 5015 | indicateOptimisticFixpoint(); | ||||||||
| 5016 | AANoCaptureImpl::initialize(A); | ||||||||
| 5017 | } | ||||||||
| 5018 | |||||||||
| 5019 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 5020 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5021 | // TODO: Once we have call site specific value information we can provide | ||||||||
| 5022 | // call site specific liveness information and then it makes | ||||||||
| 5023 | // sense to specialize attributes for call sites arguments instead of | ||||||||
| 5024 | // redirecting requests to the callee argument. | ||||||||
| 5025 | Argument *Arg = getAssociatedArgument(); | ||||||||
| 5026 | if (!Arg) | ||||||||
| 5027 | return indicatePessimisticFixpoint(); | ||||||||
| 5028 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||||||
| 5029 | auto &ArgAA = A.getAAFor<AANoCapture>(*this, ArgPos, DepClassTy::REQUIRED); | ||||||||
| 5030 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||||||
| 5031 | } | ||||||||
| 5032 | |||||||||
| 5033 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5034 | void trackStatistics() const override{STATS_DECLTRACK_CSARG_ATTR(nocapture){ static llvm::Statistic NumIRCSArguments_nocapture = {"attributor" , "NumIRCSArguments_nocapture", ("Number of " "call site arguments" " marked '" "nocapture" "'")};; ++(NumIRCSArguments_nocapture ); }}; | ||||||||
| 5035 | }; | ||||||||
| 5036 | |||||||||
| 5037 | /// NoCapture attribute for floating values. | ||||||||
| 5038 | struct AANoCaptureFloating final : AANoCaptureImpl { | ||||||||
| 5039 | AANoCaptureFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 5040 | : AANoCaptureImpl(IRP, A) {} | ||||||||
| 5041 | |||||||||
| 5042 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5043 | void trackStatistics() const override { | ||||||||
| 5044 | STATS_DECLTRACK_FLOATING_ATTR(nocapture){ static llvm::Statistic NumIRFloating_nocapture = {"attributor" , "NumIRFloating_nocapture", ("Number of floating values known to be '" "nocapture" "'")};; ++(NumIRFloating_nocapture); } | ||||||||
| 5045 | } | ||||||||
| 5046 | }; | ||||||||
| 5047 | |||||||||
| 5048 | /// NoCapture attribute for function return value. | ||||||||
| 5049 | struct AANoCaptureReturned final : AANoCaptureImpl { | ||||||||
| 5050 | AANoCaptureReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 5051 | : AANoCaptureImpl(IRP, A) { | ||||||||
| 5052 | llvm_unreachable("NoCapture is not applicable to function returns!")__builtin_unreachable(); | ||||||||
| 5053 | } | ||||||||
| 5054 | |||||||||
| 5055 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5056 | void initialize(Attributor &A) override { | ||||||||
| 5057 | llvm_unreachable("NoCapture is not applicable to function returns!")__builtin_unreachable(); | ||||||||
| 5058 | } | ||||||||
| 5059 | |||||||||
| 5060 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 5061 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5062 | llvm_unreachable("NoCapture is not applicable to function returns!")__builtin_unreachable(); | ||||||||
| 5063 | } | ||||||||
| 5064 | |||||||||
| 5065 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5066 | void trackStatistics() const override {} | ||||||||
| 5067 | }; | ||||||||
| 5068 | |||||||||
| 5069 | /// NoCapture attribute deduction for a call site return value. | ||||||||
| 5070 | struct AANoCaptureCallSiteReturned final : AANoCaptureImpl { | ||||||||
| 5071 | AANoCaptureCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 5072 | : AANoCaptureImpl(IRP, A) {} | ||||||||
| 5073 | |||||||||
| 5074 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5075 | void initialize(Attributor &A) override { | ||||||||
| 5076 | const Function *F = getAnchorScope(); | ||||||||
| 5077 | // Check what state the associated function can actually capture. | ||||||||
| 5078 | determineFunctionCaptureCapabilities(getIRPosition(), *F, *this); | ||||||||
| 5079 | } | ||||||||
| 5080 | |||||||||
| 5081 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5082 | void trackStatistics() const override { | ||||||||
| 5083 | STATS_DECLTRACK_CSRET_ATTR(nocapture){ static llvm::Statistic NumIRCSReturn_nocapture = {"attributor" , "NumIRCSReturn_nocapture", ("Number of " "call site returns" " marked '" "nocapture" "'")};; ++(NumIRCSReturn_nocapture); } | ||||||||
| 5084 | } | ||||||||
| 5085 | }; | ||||||||
| 5086 | |||||||||
| 5087 | /// ------------------ Value Simplify Attribute ---------------------------- | ||||||||
| 5088 | |||||||||
| 5089 | bool ValueSimplifyStateType::unionAssumed(Optional<Value *> Other) { | ||||||||
| 5090 | // FIXME: Add a typecast support. | ||||||||
| 5091 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||||||
| 5092 | SimplifiedAssociatedValue, Other, Ty); | ||||||||
| 5093 | if (SimplifiedAssociatedValue == Optional<Value *>(nullptr)) | ||||||||
| 5094 | return false; | ||||||||
| 5095 | |||||||||
| 5096 | LLVM_DEBUG({do { } while (false) | ||||||||
| 5097 | if (SimplifiedAssociatedValue.hasValue())do { } while (false) | ||||||||
| 5098 | dbgs() << "[ValueSimplify] is assumed to be "do { } while (false) | ||||||||
| 5099 | << **SimplifiedAssociatedValue << "\n";do { } while (false) | ||||||||
| 5100 | elsedo { } while (false) | ||||||||
| 5101 | dbgs() << "[ValueSimplify] is assumed to be <none>\n";do { } while (false) | ||||||||
| 5102 | })do { } while (false); | ||||||||
| 5103 | return true; | ||||||||
| 5104 | } | ||||||||
| 5105 | |||||||||
| 5106 | struct AAValueSimplifyImpl : AAValueSimplify { | ||||||||
| 5107 | AAValueSimplifyImpl(const IRPosition &IRP, Attributor &A) | ||||||||
| 5108 | : AAValueSimplify(IRP, A) {} | ||||||||
| 5109 | |||||||||
| 5110 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5111 | void initialize(Attributor &A) override { | ||||||||
| 5112 | if (getAssociatedValue().getType()->isVoidTy()) | ||||||||
| 5113 | indicatePessimisticFixpoint(); | ||||||||
| 5114 | if (A.hasSimplificationCallback(getIRPosition())) | ||||||||
| 5115 | indicatePessimisticFixpoint(); | ||||||||
| 5116 | } | ||||||||
| 5117 | |||||||||
| 5118 | /// See AbstractAttribute::getAsStr(). | ||||||||
| 5119 | const std::string getAsStr() const override { | ||||||||
| 5120 | LLVM_DEBUG({do { } while (false) | ||||||||
| 5121 | errs() << "SAV: " << SimplifiedAssociatedValue << " ";do { } while (false) | ||||||||
| 5122 | if (SimplifiedAssociatedValue && *SimplifiedAssociatedValue)do { } while (false) | ||||||||
| 5123 | errs() << "SAV: " << **SimplifiedAssociatedValue << " ";do { } while (false) | ||||||||
| 5124 | })do { } while (false); | ||||||||
| 5125 | return isValidState() ? (isAtFixpoint() ? "simplified" : "maybe-simple") | ||||||||
| 5126 | : "not-simple"; | ||||||||
| 5127 | } | ||||||||
| 5128 | |||||||||
| 5129 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5130 | void trackStatistics() const override {} | ||||||||
| 5131 | |||||||||
| 5132 | /// See AAValueSimplify::getAssumedSimplifiedValue() | ||||||||
| 5133 | Optional<Value *> getAssumedSimplifiedValue(Attributor &A) const override { | ||||||||
| 5134 | return SimplifiedAssociatedValue; | ||||||||
| 5135 | } | ||||||||
| 5136 | |||||||||
| 5137 | /// Return a value we can use as replacement for the associated one, or | ||||||||
| 5138 | /// nullptr if we don't have one that makes sense. | ||||||||
| 5139 | Value *getReplacementValue(Attributor &A) const { | ||||||||
| 5140 | Value *NewV; | ||||||||
| 5141 | NewV = SimplifiedAssociatedValue.hasValue() | ||||||||
| 5142 | ? SimplifiedAssociatedValue.getValue() | ||||||||
| 5143 | : UndefValue::get(getAssociatedType()); | ||||||||
| 5144 | if (!NewV) | ||||||||
| 5145 | return nullptr; | ||||||||
| 5146 | NewV = AA::getWithType(*NewV, *getAssociatedType()); | ||||||||
| 5147 | if (!NewV || NewV == &getAssociatedValue()) | ||||||||
| 5148 | return nullptr; | ||||||||
| 5149 | const Instruction *CtxI = getCtxI(); | ||||||||
| 5150 | if (CtxI && !AA::isValidAtPosition(*NewV, *CtxI, A.getInfoCache())) | ||||||||
| 5151 | return nullptr; | ||||||||
| 5152 | if (!CtxI && !AA::isValidInScope(*NewV, getAnchorScope())) | ||||||||
| 5153 | return nullptr; | ||||||||
| 5154 | return NewV; | ||||||||
| 5155 | } | ||||||||
| 5156 | |||||||||
| 5157 | /// Helper function for querying AAValueSimplify and updating candicate. | ||||||||
| 5158 | /// \param IRP The value position we are trying to unify with SimplifiedValue | ||||||||
| 5159 | bool checkAndUpdate(Attributor &A, const AbstractAttribute &QueryingAA, | ||||||||
| 5160 | const IRPosition &IRP, bool Simplify = true) { | ||||||||
| 5161 | bool UsedAssumedInformation = false; | ||||||||
| 5162 | Optional<Value *> QueryingValueSimplified = &IRP.getAssociatedValue(); | ||||||||
| 5163 | if (Simplify) | ||||||||
| 5164 | QueryingValueSimplified = | ||||||||
| 5165 | A.getAssumedSimplified(IRP, QueryingAA, UsedAssumedInformation); | ||||||||
| 5166 | return unionAssumed(QueryingValueSimplified); | ||||||||
| 5167 | } | ||||||||
| 5168 | |||||||||
| 5169 | /// Returns a candidate is found or not | ||||||||
| 5170 | template <typename AAType> bool askSimplifiedValueFor(Attributor &A) { | ||||||||
| 5171 | if (!getAssociatedValue().getType()->isIntegerTy()) | ||||||||
| 5172 | return false; | ||||||||
| 5173 | |||||||||
| 5174 | // This will also pass the call base context. | ||||||||
| 5175 | const auto &AA = | ||||||||
| 5176 | A.getAAFor<AAType>(*this, getIRPosition(), DepClassTy::NONE); | ||||||||
| 5177 | |||||||||
| 5178 | Optional<ConstantInt *> COpt = AA.getAssumedConstantInt(A); | ||||||||
| 5179 | |||||||||
| 5180 | if (!COpt.hasValue()) { | ||||||||
| 5181 | SimplifiedAssociatedValue = llvm::None; | ||||||||
| 5182 | A.recordDependence(AA, *this, DepClassTy::OPTIONAL); | ||||||||
| 5183 | return true; | ||||||||
| 5184 | } | ||||||||
| 5185 | if (auto *C = COpt.getValue()) { | ||||||||
| 5186 | SimplifiedAssociatedValue = C; | ||||||||
| 5187 | A.recordDependence(AA, *this, DepClassTy::OPTIONAL); | ||||||||
| 5188 | return true; | ||||||||
| 5189 | } | ||||||||
| 5190 | return false; | ||||||||
| 5191 | } | ||||||||
| 5192 | |||||||||
| 5193 | bool askSimplifiedValueForOtherAAs(Attributor &A) { | ||||||||
| 5194 | if (askSimplifiedValueFor<AAValueConstantRange>(A)) | ||||||||
| 5195 | return true; | ||||||||
| 5196 | if (askSimplifiedValueFor<AAPotentialValues>(A)) | ||||||||
| 5197 | return true; | ||||||||
| 5198 | return false; | ||||||||
| 5199 | } | ||||||||
| 5200 | |||||||||
| 5201 | /// See AbstractAttribute::manifest(...). | ||||||||
| 5202 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 5203 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 5204 | if (getAssociatedValue().user_empty()) | ||||||||
| 5205 | return Changed; | ||||||||
| 5206 | |||||||||
| 5207 | if (auto *NewV = getReplacementValue(A)) { | ||||||||
| 5208 | LLVM_DEBUG(dbgs() << "[ValueSimplify] " << getAssociatedValue() << " -> "do { } while (false) | ||||||||
| 5209 | << *NewV << " :: " << *this << "\n")do { } while (false); | ||||||||
| 5210 | if (A.changeValueAfterManifest(getAssociatedValue(), *NewV)) | ||||||||
| 5211 | Changed = ChangeStatus::CHANGED; | ||||||||
| 5212 | } | ||||||||
| 5213 | |||||||||
| 5214 | return Changed | AAValueSimplify::manifest(A); | ||||||||
| 5215 | } | ||||||||
| 5216 | |||||||||
| 5217 | /// See AbstractState::indicatePessimisticFixpoint(...). | ||||||||
| 5218 | ChangeStatus indicatePessimisticFixpoint() override { | ||||||||
| 5219 | SimplifiedAssociatedValue = &getAssociatedValue(); | ||||||||
| 5220 | return AAValueSimplify::indicatePessimisticFixpoint(); | ||||||||
| 5221 | } | ||||||||
| 5222 | |||||||||
| 5223 | static bool handleLoad(Attributor &A, const AbstractAttribute &AA, | ||||||||
| 5224 | LoadInst &L, function_ref<bool(Value &)> Union) { | ||||||||
| 5225 | auto UnionWrapper = [&](Value &V, Value &Obj) { | ||||||||
| 5226 | if (isa<AllocaInst>(Obj)) | ||||||||
| 5227 | return Union(V); | ||||||||
| 5228 | if (!AA::isDynamicallyUnique(A, AA, V)) | ||||||||
| 5229 | return false; | ||||||||
| 5230 | if (!AA::isValidAtPosition(V, L, A.getInfoCache())) | ||||||||
| 5231 | return false; | ||||||||
| 5232 | return Union(V); | ||||||||
| 5233 | }; | ||||||||
| 5234 | |||||||||
| 5235 | Value &Ptr = *L.getPointerOperand(); | ||||||||
| 5236 | SmallVector<Value *, 8> Objects; | ||||||||
| 5237 | if (!AA::getAssumedUnderlyingObjects(A, Ptr, Objects, AA, &L)) | ||||||||
| 5238 | return false; | ||||||||
| 5239 | |||||||||
| 5240 | for (Value *Obj : Objects) { | ||||||||
| 5241 | LLVM_DEBUG(dbgs() << "Visit underlying object " << *Obj << "\n")do { } while (false); | ||||||||
| 5242 | if (isa<UndefValue>(Obj)) | ||||||||
| 5243 | continue; | ||||||||
| 5244 | if (isa<ConstantPointerNull>(Obj)) { | ||||||||
| 5245 | // A null pointer access can be undefined but any offset from null may | ||||||||
| 5246 | // be OK. We do not try to optimize the latter. | ||||||||
| 5247 | bool UsedAssumedInformation = false; | ||||||||
| 5248 | if (!NullPointerIsDefined(L.getFunction(), | ||||||||
| 5249 | Ptr.getType()->getPointerAddressSpace()) && | ||||||||
| 5250 | A.getAssumedSimplified(Ptr, AA, UsedAssumedInformation) == Obj) | ||||||||
| 5251 | continue; | ||||||||
| 5252 | return false; | ||||||||
| 5253 | } | ||||||||
| 5254 | if (!isa<AllocaInst>(Obj) && !isa<GlobalVariable>(Obj)) | ||||||||
| 5255 | return false; | ||||||||
| 5256 | Constant *InitialVal = AA::getInitialValueForObj(*Obj, *L.getType()); | ||||||||
| 5257 | if (!InitialVal || !Union(*InitialVal)) | ||||||||
| 5258 | return false; | ||||||||
| 5259 | |||||||||
| 5260 | LLVM_DEBUG(dbgs() << "Underlying object amenable to load-store "do { } while (false) | ||||||||
| 5261 | "propagation, checking accesses next.\n")do { } while (false); | ||||||||
| 5262 | |||||||||
| 5263 | auto CheckAccess = [&](const AAPointerInfo::Access &Acc, bool IsExact) { | ||||||||
| 5264 | LLVM_DEBUG(dbgs() << " - visit access " << Acc << "\n")do { } while (false); | ||||||||
| 5265 | if (!Acc.isWrite()) | ||||||||
| 5266 | return true; | ||||||||
| 5267 | if (Acc.isWrittenValueYetUndetermined()) | ||||||||
| 5268 | return true; | ||||||||
| 5269 | Value *Content = Acc.getWrittenValue(); | ||||||||
| 5270 | if (!Content) | ||||||||
| 5271 | return false; | ||||||||
| 5272 | Value *CastedContent = | ||||||||
| 5273 | AA::getWithType(*Content, *AA.getAssociatedType()); | ||||||||
| 5274 | if (!CastedContent) | ||||||||
| 5275 | return false; | ||||||||
| 5276 | if (IsExact) | ||||||||
| 5277 | return UnionWrapper(*CastedContent, *Obj); | ||||||||
| 5278 | if (auto *C = dyn_cast<Constant>(CastedContent)) | ||||||||
| 5279 | if (C->isNullValue() || C->isAllOnesValue() || isa<UndefValue>(C)) | ||||||||
| 5280 | return UnionWrapper(*CastedContent, *Obj); | ||||||||
| 5281 | return false; | ||||||||
| 5282 | }; | ||||||||
| 5283 | |||||||||
| 5284 | auto &PI = A.getAAFor<AAPointerInfo>(AA, IRPosition::value(*Obj), | ||||||||
| 5285 | DepClassTy::REQUIRED); | ||||||||
| 5286 | if (!PI.forallInterferingAccesses(L, CheckAccess)) | ||||||||
| 5287 | return false; | ||||||||
| 5288 | } | ||||||||
| 5289 | return true; | ||||||||
| 5290 | } | ||||||||
| 5291 | }; | ||||||||
| 5292 | |||||||||
| 5293 | struct AAValueSimplifyArgument final : AAValueSimplifyImpl { | ||||||||
| 5294 | AAValueSimplifyArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 5295 | : AAValueSimplifyImpl(IRP, A) {} | ||||||||
| 5296 | |||||||||
| 5297 | void initialize(Attributor &A) override { | ||||||||
| 5298 | AAValueSimplifyImpl::initialize(A); | ||||||||
| 5299 | if (!getAnchorScope() || getAnchorScope()->isDeclaration()) | ||||||||
| 5300 | indicatePessimisticFixpoint(); | ||||||||
| 5301 | if (hasAttr({Attribute::InAlloca, Attribute::Preallocated, | ||||||||
| 5302 | Attribute::StructRet, Attribute::Nest, Attribute::ByVal}, | ||||||||
| 5303 | /* IgnoreSubsumingPositions */ true)) | ||||||||
| 5304 | indicatePessimisticFixpoint(); | ||||||||
| 5305 | |||||||||
| 5306 | // FIXME: This is a hack to prevent us from propagating function poiner in | ||||||||
| 5307 | // the new pass manager CGSCC pass as it creates call edges the | ||||||||
| 5308 | // CallGraphUpdater cannot handle yet. | ||||||||
| 5309 | Value &V = getAssociatedValue(); | ||||||||
| 5310 | if (V.getType()->isPointerTy() && | ||||||||
| 5311 | V.getType()->getPointerElementType()->isFunctionTy() && | ||||||||
| 5312 | !A.isModulePass()) | ||||||||
| 5313 | indicatePessimisticFixpoint(); | ||||||||
| 5314 | } | ||||||||
| 5315 | |||||||||
| 5316 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 5317 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5318 | // Byval is only replacable if it is readonly otherwise we would write into | ||||||||
| 5319 | // the replaced value and not the copy that byval creates implicitly. | ||||||||
| 5320 | Argument *Arg = getAssociatedArgument(); | ||||||||
| 5321 | if (Arg->hasByValAttr()) { | ||||||||
| 5322 | // TODO: We probably need to verify synchronization is not an issue, e.g., | ||||||||
| 5323 | // there is no race by not copying a constant byval. | ||||||||
| 5324 | const auto &MemAA = A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), | ||||||||
| 5325 | DepClassTy::REQUIRED); | ||||||||
| 5326 | if (!MemAA.isAssumedReadOnly()) | ||||||||
| 5327 | return indicatePessimisticFixpoint(); | ||||||||
| 5328 | } | ||||||||
| 5329 | |||||||||
| 5330 | auto Before = SimplifiedAssociatedValue; | ||||||||
| 5331 | |||||||||
| 5332 | auto PredForCallSite = [&](AbstractCallSite ACS) { | ||||||||
| 5333 | const IRPosition &ACSArgPos = | ||||||||
| 5334 | IRPosition::callsite_argument(ACS, getCallSiteArgNo()); | ||||||||
| 5335 | // Check if a coresponding argument was found or if it is on not | ||||||||
| 5336 | // associated (which can happen for callback calls). | ||||||||
| 5337 | if (ACSArgPos.getPositionKind() == IRPosition::IRP_INVALID) | ||||||||
| 5338 | return false; | ||||||||
| 5339 | |||||||||
| 5340 | // Simplify the argument operand explicitly and check if the result is | ||||||||
| 5341 | // valid in the current scope. This avoids refering to simplified values | ||||||||
| 5342 | // in other functions, e.g., we don't want to say a an argument in a | ||||||||
| 5343 | // static function is actually an argument in a different function. | ||||||||
| 5344 | bool UsedAssumedInformation = false; | ||||||||
| 5345 | Optional<Constant *> SimpleArgOp = | ||||||||
| 5346 | A.getAssumedConstant(ACSArgPos, *this, UsedAssumedInformation); | ||||||||
| 5347 | if (!SimpleArgOp.hasValue()) | ||||||||
| 5348 | return true; | ||||||||
| 5349 | if (!SimpleArgOp.getValue()) | ||||||||
| 5350 | return false; | ||||||||
| 5351 | if (!AA::isDynamicallyUnique(A, *this, **SimpleArgOp)) | ||||||||
| 5352 | return false; | ||||||||
| 5353 | return unionAssumed(*SimpleArgOp); | ||||||||
| 5354 | }; | ||||||||
| 5355 | |||||||||
| 5356 | // Generate a answer specific to a call site context. | ||||||||
| 5357 | bool Success; | ||||||||
| 5358 | bool AllCallSitesKnown; | ||||||||
| 5359 | if (hasCallBaseContext() && | ||||||||
| 5360 | getCallBaseContext()->getCalledFunction() == Arg->getParent()) | ||||||||
| 5361 | Success = PredForCallSite( | ||||||||
| 5362 | AbstractCallSite(&getCallBaseContext()->getCalledOperandUse())); | ||||||||
| 5363 | else | ||||||||
| 5364 | Success = A.checkForAllCallSites(PredForCallSite, *this, true, | ||||||||
| 5365 | AllCallSitesKnown); | ||||||||
| 5366 | |||||||||
| 5367 | if (!Success) | ||||||||
| 5368 | if (!askSimplifiedValueForOtherAAs(A)) | ||||||||
| 5369 | return indicatePessimisticFixpoint(); | ||||||||
| 5370 | |||||||||
| 5371 | // If a candicate was found in this update, return CHANGED. | ||||||||
| 5372 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||||||
| 5373 | : ChangeStatus ::CHANGED; | ||||||||
| 5374 | } | ||||||||
| 5375 | |||||||||
| 5376 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5377 | void trackStatistics() const override { | ||||||||
| 5378 | STATS_DECLTRACK_ARG_ATTR(value_simplify){ static llvm::Statistic NumIRArguments_value_simplify = {"attributor" , "NumIRArguments_value_simplify", ("Number of " "arguments" " marked '" "value_simplify" "'")};; ++(NumIRArguments_value_simplify); } | ||||||||
| 5379 | } | ||||||||
| 5380 | }; | ||||||||
| 5381 | |||||||||
| 5382 | struct AAValueSimplifyReturned : AAValueSimplifyImpl { | ||||||||
| 5383 | AAValueSimplifyReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 5384 | : AAValueSimplifyImpl(IRP, A) {} | ||||||||
| 5385 | |||||||||
| 5386 | /// See AAValueSimplify::getAssumedSimplifiedValue() | ||||||||
| 5387 | Optional<Value *> getAssumedSimplifiedValue(Attributor &A) const override { | ||||||||
| 5388 | if (!isValidState()) | ||||||||
| 5389 | return nullptr; | ||||||||
| 5390 | return SimplifiedAssociatedValue; | ||||||||
| 5391 | } | ||||||||
| 5392 | |||||||||
| 5393 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 5394 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5395 | auto Before = SimplifiedAssociatedValue; | ||||||||
| 5396 | |||||||||
| 5397 | auto PredForReturned = [&](Value &V) { | ||||||||
| 5398 | return checkAndUpdate(A, *this, | ||||||||
| 5399 | IRPosition::value(V, getCallBaseContext())); | ||||||||
| 5400 | }; | ||||||||
| 5401 | |||||||||
| 5402 | if (!A.checkForAllReturnedValues(PredForReturned, *this)) | ||||||||
| 5403 | if (!askSimplifiedValueForOtherAAs(A)) | ||||||||
| 5404 | return indicatePessimisticFixpoint(); | ||||||||
| 5405 | |||||||||
| 5406 | // If a candicate was found in this update, return CHANGED. | ||||||||
| 5407 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||||||
| 5408 | : ChangeStatus ::CHANGED; | ||||||||
| 5409 | } | ||||||||
| 5410 | |||||||||
| 5411 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 5412 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 5413 | |||||||||
| 5414 | if (auto *NewV = getReplacementValue(A)) { | ||||||||
| 5415 | auto PredForReturned = | ||||||||
| 5416 | [&](Value &, const SmallSetVector<ReturnInst *, 4> &RetInsts) { | ||||||||
| 5417 | for (ReturnInst *RI : RetInsts) { | ||||||||
| 5418 | Value *ReturnedVal = RI->getReturnValue(); | ||||||||
| 5419 | if (ReturnedVal == NewV || isa<UndefValue>(ReturnedVal)) | ||||||||
| 5420 | return true; | ||||||||
| 5421 | assert(RI->getFunction() == getAnchorScope() &&((void)0) | ||||||||
| 5422 | "ReturnInst in wrong function!")((void)0); | ||||||||
| 5423 | LLVM_DEBUG(dbgs()do { } while (false) | ||||||||
| 5424 | << "[ValueSimplify] " << *ReturnedVal << " -> "do { } while (false) | ||||||||
| 5425 | << *NewV << " in " << *RI << " :: " << *this << "\n")do { } while (false); | ||||||||
| 5426 | if (A.changeUseAfterManifest(RI->getOperandUse(0), *NewV)) | ||||||||
| 5427 | Changed = ChangeStatus::CHANGED; | ||||||||
| 5428 | } | ||||||||
| 5429 | return true; | ||||||||
| 5430 | }; | ||||||||
| 5431 | A.checkForAllReturnedValuesAndReturnInsts(PredForReturned, *this); | ||||||||
| 5432 | } | ||||||||
| 5433 | |||||||||
| 5434 | return Changed | AAValueSimplify::manifest(A); | ||||||||
| 5435 | } | ||||||||
| 5436 | |||||||||
| 5437 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5438 | void trackStatistics() const override { | ||||||||
| 5439 | STATS_DECLTRACK_FNRET_ATTR(value_simplify){ static llvm::Statistic NumIRFunctionReturn_value_simplify = {"attributor", "NumIRFunctionReturn_value_simplify", ("Number of " "function returns" " marked '" "value_simplify" "'")};; ++(NumIRFunctionReturn_value_simplify ); } | ||||||||
| 5440 | } | ||||||||
| 5441 | }; | ||||||||
| 5442 | |||||||||
| 5443 | struct AAValueSimplifyFloating : AAValueSimplifyImpl { | ||||||||
| 5444 | AAValueSimplifyFloating(const IRPosition &IRP, Attributor &A) | ||||||||
| 5445 | : AAValueSimplifyImpl(IRP, A) {} | ||||||||
| 5446 | |||||||||
| 5447 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5448 | void initialize(Attributor &A) override { | ||||||||
| 5449 | AAValueSimplifyImpl::initialize(A); | ||||||||
| 5450 | Value &V = getAnchorValue(); | ||||||||
| 5451 | |||||||||
| 5452 | // TODO: add other stuffs | ||||||||
| 5453 | if (isa<Constant>(V)) | ||||||||
| 5454 | indicatePessimisticFixpoint(); | ||||||||
| 5455 | } | ||||||||
| 5456 | |||||||||
| 5457 | /// Check if \p Cmp is a comparison we can simplify. | ||||||||
| 5458 | /// | ||||||||
| 5459 | /// We handle multiple cases, one in which at least one operand is an | ||||||||
| 5460 | /// (assumed) nullptr. If so, try to simplify it using AANonNull on the other | ||||||||
| 5461 | /// operand. Return true if successful, in that case SimplifiedAssociatedValue | ||||||||
| 5462 | /// will be updated. | ||||||||
| 5463 | bool handleCmp(Attributor &A, CmpInst &Cmp) { | ||||||||
| 5464 | auto Union = [&](Value &V) { | ||||||||
| 5465 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||||||
| 5466 | SimplifiedAssociatedValue, &V, V.getType()); | ||||||||
| 5467 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||||||
| 5468 | }; | ||||||||
| 5469 | |||||||||
| 5470 | Value *LHS = Cmp.getOperand(0); | ||||||||
| 5471 | Value *RHS = Cmp.getOperand(1); | ||||||||
| 5472 | |||||||||
| 5473 | // Simplify the operands first. | ||||||||
| 5474 | bool UsedAssumedInformation = false; | ||||||||
| 5475 | const auto &SimplifiedLHS = | ||||||||
| 5476 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||||||
| 5477 | *this, UsedAssumedInformation); | ||||||||
| 5478 | if (!SimplifiedLHS.hasValue()) | ||||||||
| 5479 | return true; | ||||||||
| 5480 | if (!SimplifiedLHS.getValue()) | ||||||||
| 5481 | return false; | ||||||||
| 5482 | LHS = *SimplifiedLHS; | ||||||||
| 5483 | |||||||||
| 5484 | const auto &SimplifiedRHS = | ||||||||
| 5485 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||||||
| 5486 | *this, UsedAssumedInformation); | ||||||||
| 5487 | if (!SimplifiedRHS.hasValue()) | ||||||||
| 5488 | return true; | ||||||||
| 5489 | if (!SimplifiedRHS.getValue()) | ||||||||
| 5490 | return false; | ||||||||
| 5491 | RHS = *SimplifiedRHS; | ||||||||
| 5492 | |||||||||
| 5493 | LLVMContext &Ctx = Cmp.getContext(); | ||||||||
| 5494 | // Handle the trivial case first in which we don't even need to think about | ||||||||
| 5495 | // null or non-null. | ||||||||
| 5496 | if (LHS == RHS && (Cmp.isTrueWhenEqual() || Cmp.isFalseWhenEqual())) { | ||||||||
| 5497 | Constant *NewVal = | ||||||||
| 5498 | ConstantInt::get(Type::getInt1Ty(Ctx), Cmp.isTrueWhenEqual()); | ||||||||
| 5499 | if (!Union(*NewVal)) | ||||||||
| 5500 | return false; | ||||||||
| 5501 | if (!UsedAssumedInformation) | ||||||||
| 5502 | indicateOptimisticFixpoint(); | ||||||||
| 5503 | return true; | ||||||||
| 5504 | } | ||||||||
| 5505 | |||||||||
| 5506 | // From now on we only handle equalities (==, !=). | ||||||||
| 5507 | ICmpInst *ICmp = dyn_cast<ICmpInst>(&Cmp); | ||||||||
| 5508 | if (!ICmp || !ICmp->isEquality()) | ||||||||
| 5509 | return false; | ||||||||
| 5510 | |||||||||
| 5511 | bool LHSIsNull = isa<ConstantPointerNull>(LHS); | ||||||||
| 5512 | bool RHSIsNull = isa<ConstantPointerNull>(RHS); | ||||||||
| 5513 | if (!LHSIsNull && !RHSIsNull) | ||||||||
| 5514 | return false; | ||||||||
| 5515 | |||||||||
| 5516 | // Left is the nullptr ==/!= non-nullptr case. We'll use AANonNull on the | ||||||||
| 5517 | // non-nullptr operand and if we assume it's non-null we can conclude the | ||||||||
| 5518 | // result of the comparison. | ||||||||
| 5519 | assert((LHSIsNull || RHSIsNull) &&((void)0) | ||||||||
| 5520 | "Expected nullptr versus non-nullptr comparison at this point")((void)0); | ||||||||
| 5521 | |||||||||
| 5522 | // The index is the operand that we assume is not null. | ||||||||
| 5523 | unsigned PtrIdx = LHSIsNull; | ||||||||
| 5524 | auto &PtrNonNullAA = A.getAAFor<AANonNull>( | ||||||||
| 5525 | *this, IRPosition::value(*ICmp->getOperand(PtrIdx)), | ||||||||
| 5526 | DepClassTy::REQUIRED); | ||||||||
| 5527 | if (!PtrNonNullAA.isAssumedNonNull()) | ||||||||
| 5528 | return false; | ||||||||
| 5529 | UsedAssumedInformation |= !PtrNonNullAA.isKnownNonNull(); | ||||||||
| 5530 | |||||||||
| 5531 | // The new value depends on the predicate, true for != and false for ==. | ||||||||
| 5532 | Constant *NewVal = ConstantInt::get( | ||||||||
| 5533 | Type::getInt1Ty(Ctx), ICmp->getPredicate() == CmpInst::ICMP_NE); | ||||||||
| 5534 | if (!Union(*NewVal)) | ||||||||
| 5535 | return false; | ||||||||
| 5536 | |||||||||
| 5537 | if (!UsedAssumedInformation) | ||||||||
| 5538 | indicateOptimisticFixpoint(); | ||||||||
| 5539 | |||||||||
| 5540 | return true; | ||||||||
| 5541 | } | ||||||||
| 5542 | |||||||||
| 5543 | bool updateWithLoad(Attributor &A, LoadInst &L) { | ||||||||
| 5544 | auto Union = [&](Value &V) { | ||||||||
| 5545 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||||||
| 5546 | SimplifiedAssociatedValue, &V, L.getType()); | ||||||||
| 5547 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||||||
| 5548 | }; | ||||||||
| 5549 | return handleLoad(A, *this, L, Union); | ||||||||
| 5550 | } | ||||||||
| 5551 | |||||||||
| 5552 | /// Use the generic, non-optimistic InstSimplfy functionality if we managed to | ||||||||
| 5553 | /// simplify any operand of the instruction \p I. Return true if successful, | ||||||||
| 5554 | /// in that case SimplifiedAssociatedValue will be updated. | ||||||||
| 5555 | bool handleGenericInst(Attributor &A, Instruction &I) { | ||||||||
| 5556 | bool SomeSimplified = false; | ||||||||
| 5557 | bool UsedAssumedInformation = false; | ||||||||
| 5558 | |||||||||
| 5559 | SmallVector<Value *, 8> NewOps(I.getNumOperands()); | ||||||||
| 5560 | int Idx = 0; | ||||||||
| 5561 | for (Value *Op : I.operands()) { | ||||||||
| 5562 | const auto &SimplifiedOp = | ||||||||
| 5563 | A.getAssumedSimplified(IRPosition::value(*Op, getCallBaseContext()), | ||||||||
| 5564 | *this, UsedAssumedInformation); | ||||||||
| 5565 | // If we are not sure about any operand we are not sure about the entire | ||||||||
| 5566 | // instruction, we'll wait. | ||||||||
| 5567 | if (!SimplifiedOp.hasValue()) | ||||||||
| 5568 | return true; | ||||||||
| 5569 | |||||||||
| 5570 | if (SimplifiedOp.getValue()) | ||||||||
| 5571 | NewOps[Idx] = SimplifiedOp.getValue(); | ||||||||
| 5572 | else | ||||||||
| 5573 | NewOps[Idx] = Op; | ||||||||
| 5574 | |||||||||
| 5575 | SomeSimplified |= (NewOps[Idx] != Op); | ||||||||
| 5576 | ++Idx; | ||||||||
| 5577 | } | ||||||||
| 5578 | |||||||||
| 5579 | // We won't bother with the InstSimplify interface if we didn't simplify any | ||||||||
| 5580 | // operand ourselves. | ||||||||
| 5581 | if (!SomeSimplified) | ||||||||
| 5582 | return false; | ||||||||
| 5583 | |||||||||
| 5584 | InformationCache &InfoCache = A.getInfoCache(); | ||||||||
| 5585 | Function *F = I.getFunction(); | ||||||||
| 5586 | const auto *DT = | ||||||||
| 5587 | InfoCache.getAnalysisResultForFunction<DominatorTreeAnalysis>(*F); | ||||||||
| 5588 | const auto *TLI = A.getInfoCache().getTargetLibraryInfoForFunction(*F); | ||||||||
| 5589 | auto *AC = InfoCache.getAnalysisResultForFunction<AssumptionAnalysis>(*F); | ||||||||
| 5590 | OptimizationRemarkEmitter *ORE = nullptr; | ||||||||
| 5591 | |||||||||
| 5592 | const DataLayout &DL = I.getModule()->getDataLayout(); | ||||||||
| 5593 | SimplifyQuery Q(DL, TLI, DT, AC, &I); | ||||||||
| 5594 | if (Value *SimplifiedI = | ||||||||
| 5595 | SimplifyInstructionWithOperands(&I, NewOps, Q, ORE)) { | ||||||||
| 5596 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||||||
| 5597 | SimplifiedAssociatedValue, SimplifiedI, I.getType()); | ||||||||
| 5598 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||||||
| 5599 | } | ||||||||
| 5600 | return false; | ||||||||
| 5601 | } | ||||||||
| 5602 | |||||||||
| 5603 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 5604 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5605 | auto Before = SimplifiedAssociatedValue; | ||||||||
| 5606 | |||||||||
| 5607 | auto VisitValueCB = [&](Value &V, const Instruction *CtxI, bool &, | ||||||||
| 5608 | bool Stripped) -> bool { | ||||||||
| 5609 | auto &AA = A.getAAFor<AAValueSimplify>( | ||||||||
| 5610 | *this, IRPosition::value(V, getCallBaseContext()), | ||||||||
| 5611 | DepClassTy::REQUIRED); | ||||||||
| 5612 | if (!Stripped && this == &AA) { | ||||||||
| 5613 | |||||||||
| 5614 | if (auto *I = dyn_cast<Instruction>(&V)) { | ||||||||
| 5615 | if (auto *LI = dyn_cast<LoadInst>(&V)) | ||||||||
| 5616 | if (updateWithLoad(A, *LI)) | ||||||||
| 5617 | return true; | ||||||||
| 5618 | if (auto *Cmp = dyn_cast<CmpInst>(&V)) | ||||||||
| 5619 | if (handleCmp(A, *Cmp)) | ||||||||
| 5620 | return true; | ||||||||
| 5621 | if (handleGenericInst(A, *I)) | ||||||||
| 5622 | return true; | ||||||||
| 5623 | } | ||||||||
| 5624 | // TODO: Look the instruction and check recursively. | ||||||||
| 5625 | |||||||||
| 5626 | LLVM_DEBUG(dbgs() << "[ValueSimplify] Can't be stripped more : " << Vdo { } while (false) | ||||||||
| 5627 | << "\n")do { } while (false); | ||||||||
| 5628 | return false; | ||||||||
| 5629 | } | ||||||||
| 5630 | return checkAndUpdate(A, *this, | ||||||||
| 5631 | IRPosition::value(V, getCallBaseContext())); | ||||||||
| 5632 | }; | ||||||||
| 5633 | |||||||||
| 5634 | bool Dummy = false; | ||||||||
| 5635 | if (!genericValueTraversal<bool>(A, getIRPosition(), *this, Dummy, | ||||||||
| 5636 | VisitValueCB, getCtxI(), | ||||||||
| 5637 | /* UseValueSimplify */ false)) | ||||||||
| 5638 | if (!askSimplifiedValueForOtherAAs(A)) | ||||||||
| 5639 | return indicatePessimisticFixpoint(); | ||||||||
| 5640 | |||||||||
| 5641 | // If a candicate was found in this update, return CHANGED. | ||||||||
| 5642 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||||||
| 5643 | : ChangeStatus ::CHANGED; | ||||||||
| 5644 | } | ||||||||
| 5645 | |||||||||
| 5646 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5647 | void trackStatistics() const override { | ||||||||
| 5648 | STATS_DECLTRACK_FLOATING_ATTR(value_simplify){ static llvm::Statistic NumIRFloating_value_simplify = {"attributor" , "NumIRFloating_value_simplify", ("Number of floating values known to be '" "value_simplify" "'")};; ++(NumIRFloating_value_simplify); } | ||||||||
| 5649 | } | ||||||||
| 5650 | }; | ||||||||
| 5651 | |||||||||
| 5652 | struct AAValueSimplifyFunction : AAValueSimplifyImpl { | ||||||||
| 5653 | AAValueSimplifyFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 5654 | : AAValueSimplifyImpl(IRP, A) {} | ||||||||
| 5655 | |||||||||
| 5656 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5657 | void initialize(Attributor &A) override { | ||||||||
| 5658 | SimplifiedAssociatedValue = nullptr; | ||||||||
| 5659 | indicateOptimisticFixpoint(); | ||||||||
| 5660 | } | ||||||||
| 5661 | /// See AbstractAttribute::initialize(...). | ||||||||
| 5662 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5663 | llvm_unreachable(__builtin_unreachable() | ||||||||
| 5664 | "AAValueSimplify(Function|CallSite)::updateImpl will not be called")__builtin_unreachable(); | ||||||||
| 5665 | } | ||||||||
| 5666 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5667 | void trackStatistics() const override { | ||||||||
| 5668 | STATS_DECLTRACK_FN_ATTR(value_simplify){ static llvm::Statistic NumIRFunction_value_simplify = {"attributor" , "NumIRFunction_value_simplify", ("Number of " "functions" " marked '" "value_simplify" "'")};; ++(NumIRFunction_value_simplify); } | ||||||||
| 5669 | } | ||||||||
| 5670 | }; | ||||||||
| 5671 | |||||||||
| 5672 | struct AAValueSimplifyCallSite : AAValueSimplifyFunction { | ||||||||
| 5673 | AAValueSimplifyCallSite(const IRPosition &IRP, Attributor &A) | ||||||||
| 5674 | : AAValueSimplifyFunction(IRP, A) {} | ||||||||
| 5675 | /// See AbstractAttribute::trackStatistics() | ||||||||
| 5676 | void trackStatistics() const override { | ||||||||
| 5677 | STATS_DECLTRACK_CS_ATTR(value_simplify){ static llvm::Statistic NumIRCS_value_simplify = {"attributor" , "NumIRCS_value_simplify", ("Number of " "call site" " marked '" "value_simplify" "'")};; ++(NumIRCS_value_simplify); } | ||||||||
| 5678 | } | ||||||||
| 5679 | }; | ||||||||
| 5680 | |||||||||
| 5681 | struct AAValueSimplifyCallSiteReturned : AAValueSimplifyImpl { | ||||||||
| 5682 | AAValueSimplifyCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||||||
| 5683 | : AAValueSimplifyImpl(IRP, A) {} | ||||||||
| 5684 | |||||||||
| 5685 | void initialize(Attributor &A) override { | ||||||||
| 5686 | AAValueSimplifyImpl::initialize(A); | ||||||||
| 5687 | if (!getAssociatedFunction()) | ||||||||
| 5688 | indicatePessimisticFixpoint(); | ||||||||
| 5689 | } | ||||||||
| 5690 | |||||||||
| 5691 | /// See AbstractAttribute::updateImpl(...). | ||||||||
| 5692 | ChangeStatus updateImpl(Attributor &A) override { | ||||||||
| 5693 | auto Before = SimplifiedAssociatedValue; | ||||||||
| 5694 | auto &RetAA = A.getAAFor<AAReturnedValues>( | ||||||||
| 5695 | *this, IRPosition::function(*getAssociatedFunction()), | ||||||||
| 5696 | DepClassTy::REQUIRED); | ||||||||
| 5697 | auto PredForReturned = | ||||||||
| 5698 | [&](Value &RetVal, const SmallSetVector<ReturnInst *, 4> &RetInsts) { | ||||||||
| 5699 | bool UsedAssumedInformation = false; | ||||||||
| 5700 | Optional<Value *> CSRetVal = A.translateArgumentToCallSiteContent( | ||||||||
| 5701 | &RetVal, *cast<CallBase>(getCtxI()), *this, | ||||||||
| 5702 | UsedAssumedInformation); | ||||||||
| 5703 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||||||
| 5704 | SimplifiedAssociatedValue, CSRetVal, getAssociatedType()); | ||||||||
| 5705 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||||||
| 5706 | }; | ||||||||
| 5707 | if (!RetAA.checkForAllReturnedValuesAndReturnInsts(PredForReturned)) | ||||||||
| 5708 | if (!askSimplifiedValueForOtherAAs(A)) | ||||||||
| 5709 | return indicatePessimisticFixpoint(); | ||||||||
| 5710 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||||||
| 5711 | : ChangeStatus ::CHANGED; | ||||||||
| 5712 | } | ||||||||
| 5713 | |||||||||
| 5714 | void trackStatistics() const override { | ||||||||
| 5715 | STATS_DECLTRACK_CSRET_ATTR(value_simplify){ static llvm::Statistic NumIRCSReturn_value_simplify = {"attributor" , "NumIRCSReturn_value_simplify", ("Number of " "call site returns" " marked '" "value_simplify" "'")};; ++(NumIRCSReturn_value_simplify ); } | ||||||||
| 5716 | } | ||||||||
| 5717 | }; | ||||||||
| 5718 | |||||||||
| 5719 | struct AAValueSimplifyCallSiteArgument : AAValueSimplifyFloating { | ||||||||
| 5720 | AAValueSimplifyCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||||||
| 5721 | : AAValueSimplifyFloating(IRP, A) {} | ||||||||
| 5722 | |||||||||
| 5723 | /// See AbstractAttribute::manifest(...). | ||||||||
| 5724 | ChangeStatus manifest(Attributor &A) override { | ||||||||
| 5725 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||||||
| 5726 | |||||||||
| 5727 | if (auto *NewV = getReplacementValue(A)) { | ||||||||
| 5728 | Use &U = cast<CallBase>(&getAnchorValue()) | ||||||||
| 5729 | ->getArgOperandUse(getCallSiteArgNo()); | ||||||||
| 5730 | if (A.changeUseAfterManifest(U, *NewV)) | ||||||||
| 5731 | Changed = ChangeStatus::CHANGED; | ||||||||
| 5732 | } | ||||||||
| 5733 | |||||||||
| 5734 | return Changed | AAValueSimplify::manifest(A); | ||||||||
| 5735 | } | ||||||||
| 5736 | |||||||||
| 5737 | void trackStatistics() const override { | ||||||||
| 5738 | STATS_DECLTRACK_CSARG_ATTR(value_simplify){ static llvm::Statistic NumIRCSArguments_value_simplify = {"attributor" , "NumIRCSArguments_value_simplify", ("Number of " "call site arguments" " marked '" "value_simplify" "'")};; ++(NumIRCSArguments_value_simplify ); } | ||||||||
| 5739 | } | ||||||||
| 5740 | }; | ||||||||
| 5741 | |||||||||
| 5742 | /// ----------------------- Heap-To-Stack Conversion --------------------------- | ||||||||
| 5743 | struct AAHeapToStackFunction final : public AAHeapToStack { | ||||||||
| 5744 | |||||||||
| 5745 | struct AllocationInfo { | ||||||||
| 5746 | /// The call that allocates the memory. | ||||||||
| 5747 | CallBase *const CB; | ||||||||
| 5748 | |||||||||
| 5749 | /// The kind of allocation. | ||||||||
| 5750 | const enum class AllocationKind { | ||||||||
| 5751 | MALLOC, | ||||||||
| 5752 | CALLOC, | ||||||||
| 5753 | ALIGNED_ALLOC, | ||||||||
| 5754 | } Kind; | ||||||||
| 5755 | |||||||||
| 5756 | /// The library function id for the allocation. | ||||||||
| 5757 | LibFunc LibraryFunctionId = NotLibFunc; | ||||||||
| 5758 | |||||||||
| 5759 | /// The status wrt. a rewrite. | ||||||||
| 5760 | enum { | ||||||||
| 5761 | STACK_DUE_TO_USE, | ||||||||
| 5762 | STACK_DUE_TO_FREE, | ||||||||
| 5763 | INVALID, | ||||||||
| 5764 | } Status = STACK_DUE_TO_USE; | ||||||||
| 5765 | |||||||||
| 5766 | /// Flag to indicate if we encountered a use that might free this allocation | ||||||||
| 5767 | /// but which is not in the deallocation infos. | ||||||||
| 5768 | bool HasPotentiallyFreeingUnknownUses = false; | ||||||||
| 5769 | |||||||||
| 5770 | /// The set of free calls that use this allocation. | ||||||||
| 5771 | SmallPtrSet<CallBase *, 1> PotentialFreeCalls{}; | ||||||||
| 5772 | }; | ||||||||
| 5773 | |||||||||
| 5774 | struct DeallocationInfo { | ||||||||
| 5775 | /// The call that deallocates the memory. | ||||||||
| 5776 | CallBase *const CB; | ||||||||
| 5777 | |||||||||
| 5778 | /// Flag to indicate if we don't know all objects this deallocation might | ||||||||
| 5779 | /// free. | ||||||||
| 5780 | bool MightFreeUnknownObjects = false; | ||||||||
| 5781 | |||||||||
| 5782 | /// The set of allocation calls that are potentially freed. | ||||||||
| 5783 | SmallPtrSet<CallBase *, 1> PotentialAllocationCalls{}; | ||||||||
| 5784 | }; | ||||||||
| 5785 | |||||||||
| 5786 | AAHeapToStackFunction(const IRPosition &IRP, Attributor &A) | ||||||||
| 5787 | : AAHeapToStack(IRP, A) {} | ||||||||
| 5788 | |||||||||
| 5789 | ~AAHeapToStackFunction() { | ||||||||
| 5790 | // Ensure we call the destructor so we release any memory allocated in the | ||||||||
| 5791 | // sets. | ||||||||
| 5792 | for (auto &It : AllocationInfos) | ||||||||
| 5793 | It.getSecond()->~AllocationInfo(); | ||||||||
| 5794 | for (auto &It : DeallocationInfos) | ||||||||
| 5795 | It.getSecond()->~DeallocationInfo(); | ||||||||
| 5796 | } | ||||||||
| 5797 | |||||||||
| 5798 | void initialize(Attributor &A) override { | ||||||||
| 5799 | AAHeapToStack::initialize(A); | ||||||||
| 5800 | |||||||||
| 5801 | const Function *F = getAnchorScope(); | ||||||||
| 5802 | const auto *TLI = A.getInfoCache().getTargetLibraryInfoForFunction(*F); | ||||||||
| 5803 | |||||||||
| 5804 | auto AllocationIdentifierCB = [&](Instruction &I) { | ||||||||
| 5805 | CallBase *CB = dyn_cast<CallBase>(&I); | ||||||||
| 5806 | if (!CB) | ||||||||
| 5807 | return true; | ||||||||
| 5808 | if (isFreeCall(CB, TLI)) { | ||||||||
| 5809 | DeallocationInfos[CB] = new (A.Allocator) DeallocationInfo{CB}; | ||||||||
| 5810 | return true; | ||||||||
| 5811 | } | ||||||||
| 5812 | bool IsMalloc = isMallocLikeFn(CB, TLI); | ||||||||