clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ValueTracking.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model static -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/clang/libLLVM/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Analysis -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ASMParser -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/BinaryFormat -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitcode -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitcode -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitstream -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /include/llvm/CodeGen -I /include/llvm/CodeGen/PBQP -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/IR -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IR -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Coroutines -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ProfileData/Coverage -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/CodeView -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/DWARF -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/MSF -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/PDB -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Demangle -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/JITLink -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/Orc -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend/OpenACC -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend/OpenMP -I /include/llvm/CodeGen/GlobalISel -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IRReader -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/InstCombine -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/Transforms/InstCombine -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/LTO -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Linker -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/MC -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/MC/MCParser -I /include/llvm/CodeGen/MIRParser -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Object -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Option -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Passes -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ProfileData -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Scalar -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ADT -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Support -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/Symbolize -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Target -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Utils -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Vectorize -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/IPO -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/libLLVM/../include -I /usr/src/gnu/usr.bin/clang/libLLVM/obj -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -internal-isystem /usr/include/c++/v1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/usr/src/gnu/usr.bin/clang/libLLVM/obj -ferror-limit 19 -fvisibility-inlines-hidden -fwrapv -stack-protector 2 -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c++ /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Analysis/ValueTracking.cpp
1 | |
2 | |
3 | |
4 | |
5 | |
6 | |
7 | |
8 | |
9 | |
10 | |
11 | |
12 | |
13 | |
14 | #include "llvm/Analysis/ValueTracking.h" |
15 | #include "llvm/ADT/APFloat.h" |
16 | #include "llvm/ADT/APInt.h" |
17 | #include "llvm/ADT/ArrayRef.h" |
18 | #include "llvm/ADT/None.h" |
19 | #include "llvm/ADT/Optional.h" |
20 | #include "llvm/ADT/STLExtras.h" |
21 | #include "llvm/ADT/SmallPtrSet.h" |
22 | #include "llvm/ADT/SmallSet.h" |
23 | #include "llvm/ADT/SmallVector.h" |
24 | #include "llvm/ADT/StringRef.h" |
25 | #include "llvm/ADT/iterator_range.h" |
26 | #include "llvm/Analysis/AliasAnalysis.h" |
27 | #include "llvm/Analysis/AssumeBundleQueries.h" |
28 | #include "llvm/Analysis/AssumptionCache.h" |
29 | #include "llvm/Analysis/EHPersonalities.h" |
30 | #include "llvm/Analysis/GuardUtils.h" |
31 | #include "llvm/Analysis/InstructionSimplify.h" |
32 | #include "llvm/Analysis/Loads.h" |
33 | #include "llvm/Analysis/LoopInfo.h" |
34 | #include "llvm/Analysis/OptimizationRemarkEmitter.h" |
35 | #include "llvm/Analysis/TargetLibraryInfo.h" |
36 | #include "llvm/IR/Argument.h" |
37 | #include "llvm/IR/Attributes.h" |
38 | #include "llvm/IR/BasicBlock.h" |
39 | #include "llvm/IR/Constant.h" |
40 | #include "llvm/IR/ConstantRange.h" |
41 | #include "llvm/IR/Constants.h" |
42 | #include "llvm/IR/DerivedTypes.h" |
43 | #include "llvm/IR/DiagnosticInfo.h" |
44 | #include "llvm/IR/Dominators.h" |
45 | #include "llvm/IR/Function.h" |
46 | #include "llvm/IR/GetElementPtrTypeIterator.h" |
47 | #include "llvm/IR/GlobalAlias.h" |
48 | #include "llvm/IR/GlobalValue.h" |
49 | #include "llvm/IR/GlobalVariable.h" |
50 | #include "llvm/IR/InstrTypes.h" |
51 | #include "llvm/IR/Instruction.h" |
52 | #include "llvm/IR/Instructions.h" |
53 | #include "llvm/IR/IntrinsicInst.h" |
54 | #include "llvm/IR/Intrinsics.h" |
55 | #include "llvm/IR/IntrinsicsAArch64.h" |
56 | #include "llvm/IR/IntrinsicsRISCV.h" |
57 | #include "llvm/IR/IntrinsicsX86.h" |
58 | #include "llvm/IR/LLVMContext.h" |
59 | #include "llvm/IR/Metadata.h" |
60 | #include "llvm/IR/Module.h" |
61 | #include "llvm/IR/Operator.h" |
62 | #include "llvm/IR/PatternMatch.h" |
63 | #include "llvm/IR/Type.h" |
64 | #include "llvm/IR/User.h" |
65 | #include "llvm/IR/Value.h" |
66 | #include "llvm/Support/Casting.h" |
67 | #include "llvm/Support/CommandLine.h" |
68 | #include "llvm/Support/Compiler.h" |
69 | #include "llvm/Support/ErrorHandling.h" |
70 | #include "llvm/Support/KnownBits.h" |
71 | #include "llvm/Support/MathExtras.h" |
72 | #include <algorithm> |
73 | #include <array> |
74 | #include <cassert> |
75 | #include <cstdint> |
76 | #include <iterator> |
77 | #include <utility> |
78 | |
79 | using namespace llvm; |
80 | using namespace llvm::PatternMatch; |
81 | |
82 | |
83 | |
84 | static cl::opt<unsigned> DomConditionsMaxUses("dom-conditions-max-uses", |
85 | cl::Hidden, cl::init(20)); |
86 | |
87 | |
88 | |
89 | static unsigned getBitWidth(Type *Ty, const DataLayout &DL) { |
90 | if (unsigned BitWidth = Ty->getScalarSizeInBits()) |
91 | return BitWidth; |
92 | |
93 | return DL.getPointerTypeSizeInBits(Ty); |
94 | } |
95 | |
96 | namespace { |
97 | |
98 | |
99 | |
100 | |
101 | |
102 | struct Query { |
103 | const DataLayout &DL; |
104 | AssumptionCache *AC; |
105 | const Instruction *CxtI; |
106 | const DominatorTree *DT; |
107 | |
108 | |
109 | |
110 | OptimizationRemarkEmitter *ORE; |
111 | |
112 | |
113 | InstrInfoQuery IIQ; |
114 | |
115 | Query(const DataLayout &DL, AssumptionCache *AC, const Instruction *CxtI, |
116 | const DominatorTree *DT, bool UseInstrInfo, |
117 | OptimizationRemarkEmitter *ORE = nullptr) |
118 | : DL(DL), AC(AC), CxtI(CxtI), DT(DT), ORE(ORE), IIQ(UseInstrInfo) {} |
119 | }; |
120 | |
121 | } |
122 | |
123 | |
124 | |
125 | static const Instruction *safeCxtI(const Value *V, const Instruction *CxtI) { |
126 | |
127 | |
128 | if (CxtI && CxtI->getParent()) |
129 | return CxtI; |
130 | |
131 | |
132 | CxtI = dyn_cast<Instruction>(V); |
133 | if (CxtI && CxtI->getParent()) |
134 | return CxtI; |
135 | |
136 | return nullptr; |
137 | } |
138 | |
139 | static const Instruction *safeCxtI(const Value *V1, const Value *V2, const Instruction *CxtI) { |
140 | |
141 | |
142 | if (CxtI && CxtI->getParent()) |
143 | return CxtI; |
144 | |
145 | |
146 | CxtI = dyn_cast<Instruction>(V1); |
147 | if (CxtI && CxtI->getParent()) |
148 | return CxtI; |
149 | |
150 | CxtI = dyn_cast<Instruction>(V2); |
151 | if (CxtI && CxtI->getParent()) |
152 | return CxtI; |
153 | |
154 | return nullptr; |
155 | } |
156 | |
157 | static bool getShuffleDemandedElts(const ShuffleVectorInst *Shuf, |
158 | const APInt &DemandedElts, |
159 | APInt &DemandedLHS, APInt &DemandedRHS) { |
160 | |
161 | |
162 | if (isa<ScalableVectorType>(Shuf->getType())) |
163 | return false; |
164 | |
165 | int NumElts = |
166 | cast<FixedVectorType>(Shuf->getOperand(0)->getType())->getNumElements(); |
167 | int NumMaskElts = cast<FixedVectorType>(Shuf->getType())->getNumElements(); |
168 | DemandedLHS = DemandedRHS = APInt::getNullValue(NumElts); |
169 | if (DemandedElts.isNullValue()) |
170 | return true; |
171 | |
172 | if (all_of(Shuf->getShuffleMask(), [](int Elt) { return Elt == 0; })) { |
173 | DemandedLHS.setBit(0); |
174 | return true; |
175 | } |
176 | for (int i = 0; i != NumMaskElts; ++i) { |
177 | if (!DemandedElts[i]) |
178 | continue; |
179 | int M = Shuf->getMaskValue(i); |
180 | assert(M < (NumElts * 2) && "Invalid shuffle mask constant"); |
181 | |
182 | |
183 | |
184 | if (M == -1) |
185 | return false; |
186 | if (M < NumElts) |
187 | DemandedLHS.setBit(M % NumElts); |
188 | else |
189 | DemandedRHS.setBit(M % NumElts); |
190 | } |
191 | |
192 | return true; |
193 | } |
194 | |
195 | static void computeKnownBits(const Value *V, const APInt &DemandedElts, |
196 | KnownBits &Known, unsigned Depth, const Query &Q); |
197 | |
198 | static void computeKnownBits(const Value *V, KnownBits &Known, unsigned Depth, |
199 | const Query &Q) { |
200 | |
201 | |
202 | if (isa<ScalableVectorType>(V->getType())) { |
203 | Known.resetAll(); |
204 | return; |
205 | } |
206 | |
207 | auto *FVTy = dyn_cast<FixedVectorType>(V->getType()); |
208 | APInt DemandedElts = |
209 | FVTy ? APInt::getAllOnesValue(FVTy->getNumElements()) : APInt(1, 1); |
210 | computeKnownBits(V, DemandedElts, Known, Depth, Q); |
211 | } |
212 | |
213 | void llvm::computeKnownBits(const Value *V, KnownBits &Known, |
214 | const DataLayout &DL, unsigned Depth, |
215 | AssumptionCache *AC, const Instruction *CxtI, |
216 | const DominatorTree *DT, |
217 | OptimizationRemarkEmitter *ORE, bool UseInstrInfo) { |
218 | ::computeKnownBits(V, Known, Depth, |
219 | Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo, ORE)); |
220 | } |
221 | |
222 | void llvm::computeKnownBits(const Value *V, const APInt &DemandedElts, |
223 | KnownBits &Known, const DataLayout &DL, |
224 | unsigned Depth, AssumptionCache *AC, |
225 | const Instruction *CxtI, const DominatorTree *DT, |
226 | OptimizationRemarkEmitter *ORE, bool UseInstrInfo) { |
227 | ::computeKnownBits(V, DemandedElts, Known, Depth, |
228 | Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo, ORE)); |
229 | } |
230 | |
231 | static KnownBits computeKnownBits(const Value *V, const APInt &DemandedElts, |
232 | unsigned Depth, const Query &Q); |
233 | |
234 | static KnownBits computeKnownBits(const Value *V, unsigned Depth, |
235 | const Query &Q); |
236 | |
237 | KnownBits llvm::computeKnownBits(const Value *V, const DataLayout &DL, |
238 | unsigned Depth, AssumptionCache *AC, |
239 | const Instruction *CxtI, |
240 | const DominatorTree *DT, |
241 | OptimizationRemarkEmitter *ORE, |
242 | bool UseInstrInfo) { |
243 | return ::computeKnownBits( |
244 | V, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo, ORE)); |
245 | } |
246 | |
247 | KnownBits llvm::computeKnownBits(const Value *V, const APInt &DemandedElts, |
248 | const DataLayout &DL, unsigned Depth, |
249 | AssumptionCache *AC, const Instruction *CxtI, |
250 | const DominatorTree *DT, |
251 | OptimizationRemarkEmitter *ORE, |
252 | bool UseInstrInfo) { |
253 | return ::computeKnownBits( |
254 | V, DemandedElts, Depth, |
255 | Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo, ORE)); |
256 | } |
257 | |
258 | bool llvm::haveNoCommonBitsSet(const Value *LHS, const Value *RHS, |
259 | const DataLayout &DL, AssumptionCache *AC, |
260 | const Instruction *CxtI, const DominatorTree *DT, |
261 | bool UseInstrInfo) { |
262 | assert(LHS->getType() == RHS->getType() && |
263 | "LHS and RHS should have the same type"); |
264 | assert(LHS->getType()->isIntOrIntVectorTy() && |
265 | "LHS and RHS should be integers"); |
266 | |
267 | Value *M; |
268 | if (match(LHS, m_c_And(m_Not(m_Value(M)), m_Value())) && |
269 | match(RHS, m_c_And(m_Specific(M), m_Value()))) |
270 | return true; |
271 | if (match(RHS, m_c_And(m_Not(m_Value(M)), m_Value())) && |
272 | match(LHS, m_c_And(m_Specific(M), m_Value()))) |
273 | return true; |
274 | IntegerType *IT = cast<IntegerType>(LHS->getType()->getScalarType()); |
275 | KnownBits LHSKnown(IT->getBitWidth()); |
276 | KnownBits RHSKnown(IT->getBitWidth()); |
277 | computeKnownBits(LHS, LHSKnown, DL, 0, AC, CxtI, DT, nullptr, UseInstrInfo); |
278 | computeKnownBits(RHS, RHSKnown, DL, 0, AC, CxtI, DT, nullptr, UseInstrInfo); |
279 | return KnownBits::haveNoCommonBitsSet(LHSKnown, RHSKnown); |
280 | } |
281 | |
282 | bool llvm::isOnlyUsedInZeroEqualityComparison(const Instruction *CxtI) { |
283 | for (const User *U : CxtI->users()) { |
284 | if (const ICmpInst *IC = dyn_cast<ICmpInst>(U)) |
285 | if (IC->isEquality()) |
286 | if (Constant *C = dyn_cast<Constant>(IC->getOperand(1))) |
287 | if (C->isNullValue()) |
288 | continue; |
289 | return false; |
290 | } |
291 | return true; |
292 | } |
293 | |
294 | static bool isKnownToBeAPowerOfTwo(const Value *V, bool OrZero, unsigned Depth, |
295 | const Query &Q); |
296 | |
297 | bool llvm::isKnownToBeAPowerOfTwo(const Value *V, const DataLayout &DL, |
298 | bool OrZero, unsigned Depth, |
299 | AssumptionCache *AC, const Instruction *CxtI, |
300 | const DominatorTree *DT, bool UseInstrInfo) { |
301 | return ::isKnownToBeAPowerOfTwo( |
302 | V, OrZero, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo)); |
303 | } |
304 | |
305 | static bool isKnownNonZero(const Value *V, const APInt &DemandedElts, |
306 | unsigned Depth, const Query &Q); |
307 | |
308 | static bool isKnownNonZero(const Value *V, unsigned Depth, const Query &Q); |
309 | |
310 | bool llvm::isKnownNonZero(const Value *V, const DataLayout &DL, unsigned Depth, |
311 | AssumptionCache *AC, const Instruction *CxtI, |
312 | const DominatorTree *DT, bool UseInstrInfo) { |
313 | return ::isKnownNonZero(V, Depth, |
314 | Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo)); |
315 | } |
316 | |
317 | bool llvm::isKnownNonNegative(const Value *V, const DataLayout &DL, |
318 | unsigned Depth, AssumptionCache *AC, |
319 | const Instruction *CxtI, const DominatorTree *DT, |
320 | bool UseInstrInfo) { |
321 | KnownBits Known = |
322 | computeKnownBits(V, DL, Depth, AC, CxtI, DT, nullptr, UseInstrInfo); |
323 | return Known.isNonNegative(); |
324 | } |
325 | |
326 | bool llvm::isKnownPositive(const Value *V, const DataLayout &DL, unsigned Depth, |
327 | AssumptionCache *AC, const Instruction *CxtI, |
328 | const DominatorTree *DT, bool UseInstrInfo) { |
329 | if (auto *CI = dyn_cast<ConstantInt>(V)) |
330 | return CI->getValue().isStrictlyPositive(); |
331 | |
332 | |
333 | |
334 | return isKnownNonNegative(V, DL, Depth, AC, CxtI, DT, UseInstrInfo) && |
335 | isKnownNonZero(V, DL, Depth, AC, CxtI, DT, UseInstrInfo); |
336 | } |
337 | |
338 | bool llvm::isKnownNegative(const Value *V, const DataLayout &DL, unsigned Depth, |
339 | AssumptionCache *AC, const Instruction *CxtI, |
340 | const DominatorTree *DT, bool UseInstrInfo) { |
341 | KnownBits Known = |
342 | computeKnownBits(V, DL, Depth, AC, CxtI, DT, nullptr, UseInstrInfo); |
343 | return Known.isNegative(); |
344 | } |
345 | |
346 | static bool isKnownNonEqual(const Value *V1, const Value *V2, unsigned Depth, |
347 | const Query &Q); |
348 | |
349 | bool llvm::isKnownNonEqual(const Value *V1, const Value *V2, |
350 | const DataLayout &DL, AssumptionCache *AC, |
351 | const Instruction *CxtI, const DominatorTree *DT, |
352 | bool UseInstrInfo) { |
353 | return ::isKnownNonEqual(V1, V2, 0, |
354 | Query(DL, AC, safeCxtI(V2, V1, CxtI), DT, |
355 | UseInstrInfo, nullptr)); |
356 | } |
357 | |
358 | static bool MaskedValueIsZero(const Value *V, const APInt &Mask, unsigned Depth, |
359 | const Query &Q); |
360 | |
361 | bool llvm::MaskedValueIsZero(const Value *V, const APInt &Mask, |
362 | const DataLayout &DL, unsigned Depth, |
363 | AssumptionCache *AC, const Instruction *CxtI, |
364 | const DominatorTree *DT, bool UseInstrInfo) { |
365 | return ::MaskedValueIsZero( |
366 | V, Mask, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo)); |
367 | } |
368 | |
369 | static unsigned ComputeNumSignBits(const Value *V, const APInt &DemandedElts, |
370 | unsigned Depth, const Query &Q); |
371 | |
372 | static unsigned ComputeNumSignBits(const Value *V, unsigned Depth, |
373 | const Query &Q) { |
374 | |
375 | |
376 | if (isa<ScalableVectorType>(V->getType())) |
377 | return 1; |
378 | |
379 | auto *FVTy = dyn_cast<FixedVectorType>(V->getType()); |
380 | APInt DemandedElts = |
381 | FVTy ? APInt::getAllOnesValue(FVTy->getNumElements()) : APInt(1, 1); |
382 | return ComputeNumSignBits(V, DemandedElts, Depth, Q); |
383 | } |
384 | |
385 | unsigned llvm::ComputeNumSignBits(const Value *V, const DataLayout &DL, |
386 | unsigned Depth, AssumptionCache *AC, |
387 | const Instruction *CxtI, |
388 | const DominatorTree *DT, bool UseInstrInfo) { |
389 | return ::ComputeNumSignBits( |
390 | V, Depth, Query(DL, AC, safeCxtI(V, CxtI), DT, UseInstrInfo)); |
391 | } |
392 | |
393 | static void computeKnownBitsAddSub(bool Add, const Value *Op0, const Value *Op1, |
394 | bool NSW, const APInt &DemandedElts, |
395 | KnownBits &KnownOut, KnownBits &Known2, |
396 | unsigned Depth, const Query &Q) { |
397 | computeKnownBits(Op1, DemandedElts, KnownOut, Depth + 1, Q); |
398 | |
399 | |
400 | |
401 | if (KnownOut.isUnknown() && !NSW) |
402 | return; |
403 | |
404 | computeKnownBits(Op0, DemandedElts, Known2, Depth + 1, Q); |
405 | KnownOut = KnownBits::computeForAddSub(Add, NSW, Known2, KnownOut); |
406 | } |
407 | |
408 | static void computeKnownBitsMul(const Value *Op0, const Value *Op1, bool NSW, |
409 | const APInt &DemandedElts, KnownBits &Known, |
410 | KnownBits &Known2, unsigned Depth, |
411 | const Query &Q) { |
412 | computeKnownBits(Op1, DemandedElts, Known, Depth + 1, Q); |
413 | computeKnownBits(Op0, DemandedElts, Known2, Depth + 1, Q); |
414 | |
415 | bool isKnownNegative = false; |
416 | bool isKnownNonNegative = false; |
417 | |
418 | if (NSW) { |
419 | if (Op0 == Op1) { |
420 | |
421 | isKnownNonNegative = true; |
422 | } else { |
423 | bool isKnownNonNegativeOp1 = Known.isNonNegative(); |
424 | bool isKnownNonNegativeOp0 = Known2.isNonNegative(); |
425 | bool isKnownNegativeOp1 = Known.isNegative(); |
426 | bool isKnownNegativeOp0 = Known2.isNegative(); |
427 | |
428 | isKnownNonNegative = (isKnownNegativeOp1 && isKnownNegativeOp0) || |
429 | (isKnownNonNegativeOp1 && isKnownNonNegativeOp0); |
430 | |
431 | |
432 | if (!isKnownNonNegative) |
433 | isKnownNegative = |
434 | (isKnownNegativeOp1 && isKnownNonNegativeOp0 && |
435 | Known2.isNonZero()) || |
436 | (isKnownNegativeOp0 && isKnownNonNegativeOp1 && Known.isNonZero()); |
437 | } |
438 | } |
439 | |
440 | Known = KnownBits::mul(Known, Known2); |
441 | |
442 | |
443 | |
444 | |
445 | |
446 | |
447 | if (isKnownNonNegative && !Known.isNegative()) |
448 | Known.makeNonNegative(); |
449 | else if (isKnownNegative && !Known.isNonNegative()) |
450 | Known.makeNegative(); |
451 | } |
452 | |
453 | void llvm::computeKnownBitsFromRangeMetadata(const MDNode &Ranges, |
454 | KnownBits &Known) { |
455 | unsigned BitWidth = Known.getBitWidth(); |
456 | unsigned NumRanges = Ranges.getNumOperands() / 2; |
457 | assert(NumRanges >= 1); |
458 | |
459 | Known.Zero.setAllBits(); |
460 | Known.One.setAllBits(); |
461 | |
462 | for (unsigned i = 0; i < NumRanges; ++i) { |
463 | ConstantInt *Lower = |
464 | mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 0)); |
465 | ConstantInt *Upper = |
466 | mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 1)); |
467 | ConstantRange Range(Lower->getValue(), Upper->getValue()); |
468 | |
469 | |
470 | unsigned CommonPrefixBits = |
471 | (Range.getUnsignedMax() ^ Range.getUnsignedMin()).countLeadingZeros(); |
472 | APInt Mask = APInt::getHighBitsSet(BitWidth, CommonPrefixBits); |
473 | APInt UnsignedMax = Range.getUnsignedMax().zextOrTrunc(BitWidth); |
474 | Known.One &= UnsignedMax & Mask; |
475 | Known.Zero &= ~UnsignedMax & Mask; |
476 | } |
477 | } |
478 | |
479 | static bool isEphemeralValueOf(const Instruction *I, const Value *E) { |
480 | SmallVector<const Value *, 16> WorkSet(1, I); |
481 | SmallPtrSet<const Value *, 32> Visited; |
482 | SmallPtrSet<const Value *, 16> EphValues; |
483 | |
484 | |
485 | |
486 | |
487 | if (is_contained(I->operands(), E)) |
488 | return true; |
489 | |
490 | while (!WorkSet.empty()) { |
491 | const Value *V = WorkSet.pop_back_val(); |
492 | if (!Visited.insert(V).second) |
493 | continue; |
494 | |
495 | |
496 | if (llvm::all_of(V->users(), [&](const User *U) { |
497 | return EphValues.count(U); |
498 | })) { |
499 | if (V == E) |
500 | return true; |
501 | |
502 | if (V == I || isSafeToSpeculativelyExecute(V)) { |
503 | EphValues.insert(V); |
504 | if (const User *U = dyn_cast<User>(V)) |
505 | append_range(WorkSet, U->operands()); |
506 | } |
507 | } |
508 | } |
509 | |
510 | return false; |
511 | } |
512 | |
513 | |
514 | bool llvm::isAssumeLikeIntrinsic(const Instruction *I) { |
515 | if (const IntrinsicInst *CI = dyn_cast<IntrinsicInst>(I)) |
516 | return CI->isAssumeLikeIntrinsic(); |
517 | |
518 | return false; |
519 | } |
520 | |
521 | bool llvm::isValidAssumeForContext(const Instruction *Inv, |
522 | const Instruction *CxtI, |
523 | const DominatorTree *DT) { |
524 | |
525 | |
526 | |
527 | |
528 | |
529 | |
530 | |
531 | |
532 | if (Inv->getParent() == CxtI->getParent()) { |
533 | |
534 | |
535 | if (Inv->comesBefore(CxtI)) |
536 | return true; |
537 | |
538 | |
539 | |
540 | |
541 | if (Inv == CxtI) |
542 | return false; |
543 | |
544 | |
545 | |
546 | |
547 | |
548 | |
549 | |
550 | unsigned ScanLimit = 15; |
551 | for (BasicBlock::const_iterator I(CxtI), IE(Inv); I != IE; ++I) |
552 | if (!isGuaranteedToTransferExecutionToSuccessor(&*I) || --ScanLimit == 0) |
553 | return false; |
554 | |
555 | return !isEphemeralValueOf(Inv, CxtI); |
556 | } |
557 | |
558 | |
559 | if (DT) { |
560 | if (DT->dominates(Inv, CxtI)) |
561 | return true; |
562 | } else if (Inv->getParent() == CxtI->getParent()->getSinglePredecessor()) { |
563 | |
564 | return true; |
565 | } |
566 | |
567 | return false; |
568 | } |
569 | |
570 | static bool cmpExcludesZero(CmpInst::Predicate Pred, const Value *RHS) { |
571 | |
572 | if (Pred == ICmpInst::ICMP_UGT) |
573 | return true; |
574 | |
575 | |
576 | if (Pred == ICmpInst::ICMP_NE) |
577 | return match(RHS, m_Zero()); |
578 | |
579 | |
580 | const APInt *C; |
581 | if (!match(RHS, m_APInt(C))) |
582 | return false; |
583 | |
584 | ConstantRange TrueValues = ConstantRange::makeExactICmpRegion(Pred, *C); |
585 | return !TrueValues.contains(APInt::getNullValue(C->getBitWidth())); |
586 | } |
587 | |
588 | static bool isKnownNonZeroFromAssume(const Value *V, const Query &Q) { |
589 | |
590 | |
591 | if (!Q.AC || !Q.CxtI) |
592 | return false; |
593 | |
594 | if (Q.CxtI && V->getType()->isPointerTy()) { |
595 | SmallVector<Attribute::AttrKind, 2> AttrKinds{Attribute::NonNull}; |
596 | if (!NullPointerIsDefined(Q.CxtI->getFunction(), |
597 | V->getType()->getPointerAddressSpace())) |
598 | AttrKinds.push_back(Attribute::Dereferenceable); |
599 | |
600 | if (getKnowledgeValidInContext(V, AttrKinds, Q.CxtI, Q.DT, Q.AC)) |
601 | return true; |
602 | } |
603 | |
604 | for (auto &AssumeVH : Q.AC->assumptionsFor(V)) { |
605 | if (!AssumeVH) |
606 | continue; |
607 | CallInst *I = cast<CallInst>(AssumeVH); |
608 | assert(I->getFunction() == Q.CxtI->getFunction() && |
609 | "Got assumption for the wrong function!"); |
610 | |
611 | |
612 | |
613 | |
614 | |
615 | assert(I->getCalledFunction()->getIntrinsicID() == Intrinsic::assume && |
616 | "must be an assume intrinsic"); |
617 | |
618 | Value *RHS; |
619 | CmpInst::Predicate Pred; |
620 | auto m_V = m_CombineOr(m_Specific(V), m_PtrToInt(m_Specific(V))); |
621 | if (!match(I->getArgOperand(0), m_c_ICmp(Pred, m_V, m_Value(RHS)))) |
622 | return false; |
623 | |
624 | if (cmpExcludesZero(Pred, RHS) && isValidAssumeForContext(I, Q.CxtI, Q.DT)) |
625 | return true; |
626 | } |
627 | |
628 | return false; |
629 | } |
630 | |
631 | static void computeKnownBitsFromAssume(const Value *V, KnownBits &Known, |
632 | unsigned Depth, const Query &Q) { |
633 | |
634 | |
635 | if (!Q.AC || !Q.CxtI) |
636 | return; |
637 | |
638 | unsigned BitWidth = Known.getBitWidth(); |
639 | |
640 | |
641 | if (V->getType()->isPointerTy()) { |
642 | if (RetainedKnowledge RK = getKnowledgeValidInContext( |
643 | V, {Attribute::Alignment}, Q.CxtI, Q.DT, Q.AC)) { |
644 | Known.Zero.setLowBits(Log2_32(RK.ArgValue)); |
645 | } |
646 | } |
647 | |
648 | |
649 | |
650 | |
651 | for (auto &AssumeVH : Q.AC->assumptionsFor(V)) { |
652 | if (!AssumeVH) |
653 | continue; |
654 | CallInst *I = cast<CallInst>(AssumeVH); |
655 | assert(I->getParent()->getParent() == Q.CxtI->getParent()->getParent() && |
656 | "Got assumption for the wrong function!"); |
657 | |
658 | |
659 | |
660 | |
661 | |
662 | assert(I->getCalledFunction()->getIntrinsicID() == Intrinsic::assume && |
663 | "must be an assume intrinsic"); |
664 | |
665 | Value *Arg = I->getArgOperand(0); |
666 | |
667 | if (Arg == V && isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
668 | assert(BitWidth == 1 && "assume operand is not i1?"); |
669 | Known.setAllOnes(); |
670 | return; |
671 | } |
672 | if (match(Arg, m_Not(m_Specific(V))) && |
673 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
674 | assert(BitWidth == 1 && "assume operand is not i1?"); |
675 | Known.setAllZero(); |
676 | return; |
677 | } |
678 | |
679 | |
680 | if (Depth == MaxAnalysisRecursionDepth) |
681 | continue; |
682 | |
683 | ICmpInst *Cmp = dyn_cast<ICmpInst>(Arg); |
684 | if (!Cmp) |
685 | continue; |
686 | |
687 | |
688 | |
689 | |
690 | |
691 | |
692 | |
693 | Query QueryNoAC = Q; |
694 | QueryNoAC.AC = nullptr; |
695 | |
696 | |
697 | Value *A, *B; |
698 | auto m_V = m_CombineOr(m_Specific(V), m_PtrToInt(m_Specific(V))); |
699 | |
700 | CmpInst::Predicate Pred; |
701 | uint64_t C; |
702 | switch (Cmp->getPredicate()) { |
703 | default: |
704 | break; |
705 | case ICmpInst::ICMP_EQ: |
706 | |
707 | if (match(Cmp, m_c_ICmp(Pred, m_V, m_Value(A))) && |
708 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
709 | KnownBits RHSKnown = |
710 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
711 | Known.Zero |= RHSKnown.Zero; |
712 | Known.One |= RHSKnown.One; |
713 | |
714 | } else if (match(Cmp, |
715 | m_c_ICmp(Pred, m_c_And(m_V, m_Value(B)), m_Value(A))) && |
716 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
717 | KnownBits RHSKnown = |
718 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
719 | KnownBits MaskKnown = |
720 | computeKnownBits(B, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
721 | |
722 | |
723 | |
724 | Known.Zero |= RHSKnown.Zero & MaskKnown.One; |
725 | Known.One |= RHSKnown.One & MaskKnown.One; |
726 | |
727 | } else if (match(Cmp, m_c_ICmp(Pred, m_Not(m_c_And(m_V, m_Value(B))), |
728 | m_Value(A))) && |
729 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
730 | KnownBits RHSKnown = |
731 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
732 | KnownBits MaskKnown = |
733 | computeKnownBits(B, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
734 | |
735 | |
736 | |
737 | Known.Zero |= RHSKnown.One & MaskKnown.One; |
738 | Known.One |= RHSKnown.Zero & MaskKnown.One; |
739 | |
740 | } else if (match(Cmp, |
741 | m_c_ICmp(Pred, m_c_Or(m_V, m_Value(B)), m_Value(A))) && |
742 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
743 | KnownBits RHSKnown = |
744 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
745 | KnownBits BKnown = |
746 | computeKnownBits(B, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
747 | |
748 | |
749 | |
750 | Known.Zero |= RHSKnown.Zero & BKnown.Zero; |
751 | Known.One |= RHSKnown.One & BKnown.Zero; |
752 | |
753 | } else if (match(Cmp, m_c_ICmp(Pred, m_Not(m_c_Or(m_V, m_Value(B))), |
754 | m_Value(A))) && |
755 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
756 | KnownBits RHSKnown = |
757 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
758 | KnownBits BKnown = |
759 | computeKnownBits(B, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
760 | |
761 | |
762 | |
763 | Known.Zero |= RHSKnown.One & BKnown.Zero; |
764 | Known.One |= RHSKnown.Zero & BKnown.Zero; |
765 | |
766 | } else if (match(Cmp, |
767 | m_c_ICmp(Pred, m_c_Xor(m_V, m_Value(B)), m_Value(A))) && |
768 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
769 | KnownBits RHSKnown = |
770 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
771 | KnownBits BKnown = |
772 | computeKnownBits(B, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
773 | |
774 | |
775 | |
776 | |
777 | Known.Zero |= RHSKnown.Zero & BKnown.Zero; |
778 | Known.One |= RHSKnown.One & BKnown.Zero; |
779 | Known.Zero |= RHSKnown.One & BKnown.One; |
780 | Known.One |= RHSKnown.Zero & BKnown.One; |
781 | |
782 | } else if (match(Cmp, m_c_ICmp(Pred, m_Not(m_c_Xor(m_V, m_Value(B))), |
783 | m_Value(A))) && |
784 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
785 | KnownBits RHSKnown = |
786 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
787 | KnownBits BKnown = |
788 | computeKnownBits(B, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
789 | |
790 | |
791 | |
792 | |
793 | Known.Zero |= RHSKnown.One & BKnown.Zero; |
794 | Known.One |= RHSKnown.Zero & BKnown.Zero; |
795 | Known.Zero |= RHSKnown.Zero & BKnown.One; |
796 | Known.One |= RHSKnown.One & BKnown.One; |
797 | |
798 | } else if (match(Cmp, m_c_ICmp(Pred, m_Shl(m_V, m_ConstantInt(C)), |
799 | m_Value(A))) && |
800 | isValidAssumeForContext(I, Q.CxtI, Q.DT) && C < BitWidth) { |
801 | KnownBits RHSKnown = |
802 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
803 | |
804 | |
805 | |
806 | RHSKnown.Zero.lshrInPlace(C); |
807 | Known.Zero |= RHSKnown.Zero; |
808 | RHSKnown.One.lshrInPlace(C); |
809 | Known.One |= RHSKnown.One; |
810 | |
811 | } else if (match(Cmp, m_c_ICmp(Pred, m_Not(m_Shl(m_V, m_ConstantInt(C))), |
812 | m_Value(A))) && |
813 | isValidAssumeForContext(I, Q.CxtI, Q.DT) && C < BitWidth) { |
814 | KnownBits RHSKnown = |
815 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
816 | |
817 | |
818 | RHSKnown.One.lshrInPlace(C); |
819 | Known.Zero |= RHSKnown.One; |
820 | RHSKnown.Zero.lshrInPlace(C); |
821 | Known.One |= RHSKnown.Zero; |
822 | |
823 | } else if (match(Cmp, m_c_ICmp(Pred, m_Shr(m_V, m_ConstantInt(C)), |
824 | m_Value(A))) && |
825 | isValidAssumeForContext(I, Q.CxtI, Q.DT) && C < BitWidth) { |
826 | KnownBits RHSKnown = |
827 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
828 | |
829 | |
830 | Known.Zero |= RHSKnown.Zero << C; |
831 | Known.One |= RHSKnown.One << C; |
832 | |
833 | } else if (match(Cmp, m_c_ICmp(Pred, m_Not(m_Shr(m_V, m_ConstantInt(C))), |
834 | m_Value(A))) && |
835 | isValidAssumeForContext(I, Q.CxtI, Q.DT) && C < BitWidth) { |
836 | KnownBits RHSKnown = |
837 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
838 | |
839 | |
840 | Known.Zero |= RHSKnown.One << C; |
841 | Known.One |= RHSKnown.Zero << C; |
842 | } |
843 | break; |
844 | case ICmpInst::ICMP_SGE: |
845 | |
846 | if (match(Cmp, m_ICmp(Pred, m_V, m_Value(A))) && |
847 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
848 | KnownBits RHSKnown = |
849 | computeKnownBits(A, Depth + 1, QueryNoAC).anyextOrTrunc(BitWidth); |
850 | |
851 | if (RHSKnown.isNonNegative()) { |
852 | |
853 | Known.makeNonNegative(); |
854 | } |
855 | } |
856 | break; |
857 | case ICmpInst::ICMP_SGT: |
858 | |
859 | if (match(Cmp, m_ICmp(Pred, m_V, m_Value(A))) && |
860 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
861 | KnownBits RHSKnown = |
862 | computeKnownBits(A, Depth + 1, QueryNoAC).anyextOrTrunc(BitWidth); |
863 | |
864 | if (RHSKnown.isAllOnes() || RHSKnown.isNonNegative()) { |
865 | |
866 | Known.makeNonNegative(); |
867 | } |
868 | } |
869 | break; |
870 | case ICmpInst::ICMP_SLE: |
871 | |
872 | if (match(Cmp, m_ICmp(Pred, m_V, m_Value(A))) && |
873 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
874 | KnownBits RHSKnown = |
875 | computeKnownBits(A, Depth + 1, QueryNoAC).anyextOrTrunc(BitWidth); |
876 | |
877 | if (RHSKnown.isNegative()) { |
878 | |
879 | Known.makeNegative(); |
880 | } |
881 | } |
882 | break; |
883 | case ICmpInst::ICMP_SLT: |
884 | |
885 | if (match(Cmp, m_ICmp(Pred, m_V, m_Value(A))) && |
886 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
887 | KnownBits RHSKnown = |
888 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
889 | |
890 | if (RHSKnown.isZero() || RHSKnown.isNegative()) { |
891 | |
892 | Known.makeNegative(); |
893 | } |
894 | } |
895 | break; |
896 | case ICmpInst::ICMP_ULE: |
897 | |
898 | if (match(Cmp, m_ICmp(Pred, m_V, m_Value(A))) && |
899 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
900 | KnownBits RHSKnown = |
901 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
902 | |
903 | |
904 | Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros()); |
905 | } |
906 | break; |
907 | case ICmpInst::ICMP_ULT: |
908 | |
909 | if (match(Cmp, m_ICmp(Pred, m_V, m_Value(A))) && |
910 | isValidAssumeForContext(I, Q.CxtI, Q.DT)) { |
911 | KnownBits RHSKnown = |
912 | computeKnownBits(A, Depth+1, QueryNoAC).anyextOrTrunc(BitWidth); |
913 | |
914 | |
915 | |
916 | if (RHSKnown.isZero()) { |
917 | Known.Zero.setAllBits(); |
918 | Known.One.setAllBits(); |
919 | break; |
920 | } |
921 | |
922 | |
923 | |
924 | if (isKnownToBeAPowerOfTwo(A, false, Depth + 1, QueryNoAC)) |
925 | Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros() + 1); |
926 | else |
927 | Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros()); |
928 | } |
929 | break; |
930 | } |
931 | } |
932 | |
933 | |
934 | |
935 | |
936 | |
937 | |
938 | if (Known.Zero.intersects(Known.One)) { |
939 | Known.resetAll(); |
940 | |
941 | if (Q.ORE) |
942 | Q.ORE->emit([&]() { |
943 | auto *CxtI = const_cast<Instruction *>(Q.CxtI); |
944 | return OptimizationRemarkAnalysis("value-tracking", "BadAssumption", |
945 | CxtI) |
946 | << "Detected conflicting code assumptions. Program may " |
947 | "have undefined behavior, or compiler may have " |
948 | "internal error."; |
949 | }); |
950 | } |
951 | } |
952 | |
953 | |
954 | |
955 | |
956 | |
957 | |
958 | |
959 | |
960 | |
961 | static void computeKnownBitsFromShiftOperator( |
962 | const Operator *I, const APInt &DemandedElts, KnownBits &Known, |
963 | KnownBits &Known2, unsigned Depth, const Query &Q, |
964 | function_ref<KnownBits(const KnownBits &, const KnownBits &)> KF) { |
965 | unsigned BitWidth = Known.getBitWidth(); |
966 | computeKnownBits(I->getOperand(0), DemandedElts, Known2, Depth + 1, Q); |
967 | computeKnownBits(I->getOperand(1), DemandedElts, Known, Depth + 1, Q); |
968 | |
969 | |
970 | |
971 | |
972 | uint64_t ShiftAmtKZ = Known.Zero.zextOrTrunc(64).getZExtValue(); |
973 | uint64_t ShiftAmtKO = Known.One.zextOrTrunc(64).getZExtValue(); |
974 | bool ShiftAmtIsConstant = Known.isConstant(); |
975 | bool MaxShiftAmtIsOutOfRange = Known.getMaxValue().uge(BitWidth); |
976 | |
977 | if (ShiftAmtIsConstant) { |
978 | Known = KF(Known2, Known); |
979 | |
980 | |
981 | |
982 | |
983 | if (Known.hasConflict()) |
984 | Known.setAllZero(); |
985 | |
986 | return; |
987 | } |
988 | |
989 | |
990 | |
991 | |
992 | |
993 | if (MaxShiftAmtIsOutOfRange) { |
994 | Known.resetAll(); |
995 | return; |
996 | } |
997 | |
998 | |
999 | |
1000 | Known.resetAll(); |
1001 | |
1002 | |
1003 | |
1004 | |
1005 | Optional<bool> ShifterOperandIsNonZero; |
1006 | |
1007 | |
1008 | if (!(ShiftAmtKZ & (PowerOf2Ceil(BitWidth) - 1)) && |
1009 | !(ShiftAmtKO & (PowerOf2Ceil(BitWidth) - 1))) { |
1010 | ShifterOperandIsNonZero = |
1011 | isKnownNonZero(I->getOperand(1), DemandedElts, Depth + 1, Q); |
1012 | if (!*ShifterOperandIsNonZero) |
1013 | return; |
1014 | } |
1015 | |
1016 | Known.Zero.setAllBits(); |
1017 | Known.One.setAllBits(); |
1018 | for (unsigned ShiftAmt = 0; ShiftAmt < BitWidth; ++ShiftAmt) { |
1019 | |
1020 | |
1021 | if ((ShiftAmt & ~ShiftAmtKZ) != ShiftAmt) |
1022 | continue; |
1023 | if ((ShiftAmt | ShiftAmtKO) != ShiftAmt) |
1024 | continue; |
1025 | |
1026 | |
1027 | |
1028 | if (ShiftAmt == 0) { |
1029 | if (!ShifterOperandIsNonZero.hasValue()) |
1030 | ShifterOperandIsNonZero = |
1031 | isKnownNonZero(I->getOperand(1), DemandedElts, Depth + 1, Q); |
1032 | if (*ShifterOperandIsNonZero) |
1033 | continue; |
1034 | } |
1035 | |
1036 | Known = KnownBits::commonBits( |
1037 | Known, KF(Known2, KnownBits::makeConstant(APInt(32, ShiftAmt)))); |
1038 | } |
1039 | |
1040 | |
1041 | |
1042 | if (Known.hasConflict()) |
1043 | Known.setAllZero(); |
1044 | } |
1045 | |
1046 | static void computeKnownBitsFromOperator(const Operator *I, |
1047 | const APInt &DemandedElts, |
1048 | KnownBits &Known, unsigned Depth, |
1049 | const Query &Q) { |
1050 | unsigned BitWidth = Known.getBitWidth(); |
1051 | |
1052 | KnownBits Known2(BitWidth); |
1053 | switch (I->getOpcode()) { |
| 1 | Calling 'Operator::getOpcode' | |
|
| 6 | | Returning from 'Operator::getOpcode' | |
|
| 7 | | Control jumps to 'case GetElementPtr:' at line 1308 | |
|
1054 | default: break; |
1055 | case Instruction::Load: |
1056 | if (MDNode *MD = |
1057 | Q.IIQ.getMetadata(cast<LoadInst>(I), LLVMContext::MD_range)) |
1058 | computeKnownBitsFromRangeMetadata(*MD, Known); |
1059 | break; |
1060 | case Instruction::And: { |
1061 | |
1062 | computeKnownBits(I->getOperand(1), DemandedElts, Known, Depth + 1, Q); |
1063 | computeKnownBits(I->getOperand(0), DemandedElts, Known2, Depth + 1, Q); |
1064 | |
1065 | Known &= Known2; |
1066 | |
1067 | |
1068 | |
1069 | |
1070 | |
1071 | |
1072 | Value *X = nullptr, *Y = nullptr; |
1073 | if (!Known.Zero[0] && !Known.One[0] && |
1074 | match(I, m_c_BinOp(m_Value(X), m_Add(m_Deferred(X), m_Value(Y))))) { |
1075 | Known2.resetAll(); |
1076 | computeKnownBits(Y, DemandedElts, Known2, Depth + 1, Q); |
1077 | if (Known2.countMinTrailingOnes() > 0) |
1078 | Known.Zero.setBit(0); |
1079 | } |
1080 | break; |
1081 | } |
1082 | case Instruction::Or: |
1083 | computeKnownBits(I->getOperand(1), DemandedElts, Known, Depth + 1, Q); |
1084 | computeKnownBits(I->getOperand(0), DemandedElts, Known2, Depth + 1, Q); |
1085 | |
1086 | Known |= Known2; |
1087 | break; |
1088 | case Instruction::Xor: |
1089 | computeKnownBits(I->getOperand(1), DemandedElts, Known, Depth + 1, Q); |
1090 | computeKnownBits(I->getOperand(0), DemandedElts, Known2, Depth + 1, Q); |
1091 | |
1092 | Known ^= Known2; |
1093 | break; |
1094 | case Instruction::Mul: { |
1095 | bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I)); |
1096 | computeKnownBitsMul(I->getOperand(0), I->getOperand(1), NSW, DemandedElts, |
1097 | Known, Known2, Depth, Q); |
1098 | break; |
1099 | } |
1100 | case Instruction::UDiv: { |
1101 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1102 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1103 | Known = KnownBits::udiv(Known, Known2); |
1104 | break; |
1105 | } |
1106 | case Instruction::Select: { |
1107 | const Value *LHS = nullptr, *RHS = nullptr; |
1108 | SelectPatternFlavor SPF = matchSelectPattern(I, LHS, RHS).Flavor; |
1109 | if (SelectPatternResult::isMinOrMax(SPF)) { |
1110 | computeKnownBits(RHS, Known, Depth + 1, Q); |
1111 | computeKnownBits(LHS, Known2, Depth + 1, Q); |
1112 | switch (SPF) { |
1113 | default: |
1114 | llvm_unreachable("Unhandled select pattern flavor!"); |
1115 | case SPF_SMAX: |
1116 | Known = KnownBits::smax(Known, Known2); |
1117 | break; |
1118 | case SPF_SMIN: |
1119 | Known = KnownBits::smin(Known, Known2); |
1120 | break; |
1121 | case SPF_UMAX: |
1122 | Known = KnownBits::umax(Known, Known2); |
1123 | break; |
1124 | case SPF_UMIN: |
1125 | Known = KnownBits::umin(Known, Known2); |
1126 | break; |
1127 | } |
1128 | break; |
1129 | } |
1130 | |
1131 | computeKnownBits(I->getOperand(2), Known, Depth + 1, Q); |
1132 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1133 | |
1134 | |
1135 | Known = KnownBits::commonBits(Known, Known2); |
1136 | |
1137 | if (SPF == SPF_ABS) { |
1138 | |
1139 | |
1140 | |
1141 | if (match(RHS, m_Neg(m_Specific(LHS))) && |
1142 | Q.IIQ.hasNoSignedWrap(cast<Instruction>(RHS))) |
1143 | Known.Zero.setSignBit(); |
1144 | } |
1145 | |
1146 | break; |
1147 | } |
1148 | case Instruction::FPTrunc: |
1149 | case Instruction::FPExt: |
1150 | case Instruction::FPToUI: |
1151 | case Instruction::FPToSI: |
1152 | case Instruction::SIToFP: |
1153 | case Instruction::UIToFP: |
1154 | break; |
1155 | case Instruction::PtrToInt: |
1156 | case Instruction::IntToPtr: |
1157 | |
1158 | LLVM_FALLTHROUGH; |
1159 | case Instruction::ZExt: |
1160 | case Instruction::Trunc: { |
1161 | Type *SrcTy = I->getOperand(0)->getType(); |
1162 | |
1163 | unsigned SrcBitWidth; |
1164 | |
1165 | |
1166 | Type *ScalarTy = SrcTy->getScalarType(); |
1167 | SrcBitWidth = ScalarTy->isPointerTy() ? |
1168 | Q.DL.getPointerTypeSizeInBits(ScalarTy) : |
1169 | Q.DL.getTypeSizeInBits(ScalarTy); |
1170 | |
1171 | assert(SrcBitWidth && "SrcBitWidth can't be zero"); |
1172 | Known = Known.anyextOrTrunc(SrcBitWidth); |
1173 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1174 | Known = Known.zextOrTrunc(BitWidth); |
1175 | break; |
1176 | } |
1177 | case Instruction::BitCast: { |
1178 | Type *SrcTy = I->getOperand(0)->getType(); |
1179 | if (SrcTy->isIntOrPtrTy() && |
1180 | |
1181 | |
1182 | !I->getType()->isVectorTy()) { |
1183 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1184 | break; |
1185 | } |
1186 | |
1187 | |
1188 | auto *SrcVecTy = dyn_cast<FixedVectorType>(SrcTy); |
1189 | if (!SrcVecTy || !SrcVecTy->getElementType()->isIntegerTy() || |
1190 | !I->getType()->isIntOrIntVectorTy()) |
1191 | break; |
1192 | |
1193 | |
1194 | |
1195 | unsigned SubBitWidth = SrcVecTy->getScalarSizeInBits(); |
1196 | if (BitWidth % SubBitWidth == 0) { |
1197 | |
1198 | |
1199 | |
1200 | |
1201 | |
1202 | |
1203 | |
1204 | |
1205 | |
1206 | |
1207 | |
1208 | |
1209 | |
1210 | |
1211 | unsigned NumElts = DemandedElts.getBitWidth(); |
1212 | unsigned SubScale = BitWidth / SubBitWidth; |
1213 | APInt SubDemandedElts = APInt::getNullValue(NumElts * SubScale); |
1214 | for (unsigned i = 0; i != NumElts; ++i) { |
1215 | if (DemandedElts[i]) |
1216 | SubDemandedElts.setBit(i * SubScale); |
1217 | } |
1218 | |
1219 | KnownBits KnownSrc(SubBitWidth); |
1220 | for (unsigned i = 0; i != SubScale; ++i) { |
1221 | computeKnownBits(I->getOperand(0), SubDemandedElts.shl(i), KnownSrc, |
1222 | Depth + 1, Q); |
1223 | unsigned ShiftElt = Q.DL.isLittleEndian() ? i : SubScale - 1 - i; |
1224 | Known.insertBits(KnownSrc, ShiftElt * SubBitWidth); |
1225 | } |
1226 | } |
1227 | break; |
1228 | } |
1229 | case Instruction::SExt: { |
1230 | |
1231 | unsigned SrcBitWidth = I->getOperand(0)->getType()->getScalarSizeInBits(); |
1232 | |
1233 | Known = Known.trunc(SrcBitWidth); |
1234 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1235 | |
1236 | |
1237 | Known = Known.sext(BitWidth); |
1238 | break; |
1239 | } |
1240 | case Instruction::Shl: { |
1241 | bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I)); |
1242 | auto KF = [NSW](const KnownBits &KnownVal, const KnownBits &KnownAmt) { |
1243 | KnownBits Result = KnownBits::shl(KnownVal, KnownAmt); |
1244 | |
1245 | |
1246 | if (NSW) { |
1247 | if (KnownVal.Zero.isSignBitSet()) |
1248 | Result.Zero.setSignBit(); |
1249 | if (KnownVal.One.isSignBitSet()) |
1250 | Result.One.setSignBit(); |
1251 | } |
1252 | return Result; |
1253 | }; |
1254 | computeKnownBitsFromShiftOperator(I, DemandedElts, Known, Known2, Depth, Q, |
1255 | KF); |
1256 | |
1257 | const APInt *C; |
1258 | if (match(I->getOperand(0), m_APInt(C))) |
1259 | Known.Zero.setLowBits(C->countTrailingZeros()); |
1260 | break; |
1261 | } |
1262 | case Instruction::LShr: { |
1263 | auto KF = [](const KnownBits &KnownVal, const KnownBits &KnownAmt) { |
1264 | return KnownBits::lshr(KnownVal, KnownAmt); |
1265 | }; |
1266 | computeKnownBitsFromShiftOperator(I, DemandedElts, Known, Known2, Depth, Q, |
1267 | KF); |
1268 | |
1269 | const APInt *C; |
1270 | if (match(I->getOperand(0), m_APInt(C))) |
1271 | Known.Zero.setHighBits(C->countLeadingZeros()); |
1272 | break; |
1273 | } |
1274 | case Instruction::AShr: { |
1275 | auto KF = [](const KnownBits &KnownVal, const KnownBits &KnownAmt) { |
1276 | return KnownBits::ashr(KnownVal, KnownAmt); |
1277 | }; |
1278 | computeKnownBitsFromShiftOperator(I, DemandedElts, Known, Known2, Depth, Q, |
1279 | KF); |
1280 | break; |
1281 | } |
1282 | case Instruction::Sub: { |
1283 | bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I)); |
1284 | computeKnownBitsAddSub(false, I->getOperand(0), I->getOperand(1), NSW, |
1285 | DemandedElts, Known, Known2, Depth, Q); |
1286 | break; |
1287 | } |
1288 | case Instruction::Add: { |
1289 | bool NSW = Q.IIQ.hasNoSignedWrap(cast<OverflowingBinaryOperator>(I)); |
1290 | computeKnownBitsAddSub(true, I->getOperand(0), I->getOperand(1), NSW, |
1291 | DemandedElts, Known, Known2, Depth, Q); |
1292 | break; |
1293 | } |
1294 | case Instruction::SRem: |
1295 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1296 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1297 | Known = KnownBits::srem(Known, Known2); |
1298 | break; |
1299 | |
1300 | case Instruction::URem: |
1301 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1302 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1303 | Known = KnownBits::urem(Known, Known2); |
1304 | break; |
1305 | case Instruction::Alloca: |
1306 | Known.Zero.setLowBits(Log2(cast<AllocaInst>(I)->getAlign())); |
1307 | break; |
1308 | case Instruction::GetElementPtr: { |
1309 | |
1310 | |
1311 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1312 | |
1313 | |
1314 | APInt AccConstIndices(BitWidth, 0, true); |
1315 | |
1316 | gep_type_iterator GTI = gep_type_begin(I); |
1317 | for (unsigned i = 1, e = I->getNumOperands(); i != e; ++i, ++GTI) { |
| 8 | | Assuming 'i' is not equal to 'e' | |
|
| 9 | | Loop condition is true. Entering loop body | |
|
1318 | |
1319 | if (Known.isUnknown()) |
| 10 | | Calling 'KnownBits::isUnknown' | |
|
| 12 | | Returning from 'KnownBits::isUnknown' | |
|
| |
1320 | break; |
1321 | |
1322 | Value *Index = I->getOperand(i); |
1323 | |
1324 | |
1325 | Constant *CIndex = dyn_cast<Constant>(Index); |
| 14 | | Assuming 'Index' is not a 'Constant' | |
|
| 15 | | 'CIndex' initialized to a null pointer value | |
|
1326 | if (CIndex && CIndex->isZeroValue()) |
1327 | continue; |
1328 | |
1329 | if (StructType *STy = GTI.getStructTypeOrNull()) { |
| 16 | | Assuming 'STy' is non-null | |
|
| |
1330 | |
1331 | |
1332 | assert(CIndex && |
1333 | "Access to structure field must be known at compile time"); |
1334 | |
1335 | if (CIndex->getType()->isVectorTy()) |
| 18 | | Called C++ object pointer is null |
|
1336 | Index = CIndex->getSplatValue(); |
1337 | |
1338 | unsigned Idx = cast<ConstantInt>(Index)->getZExtValue(); |
1339 | const StructLayout *SL = Q.DL.getStructLayout(STy); |
1340 | uint64_t Offset = SL->getElementOffset(Idx); |
1341 | AccConstIndices += Offset; |
1342 | continue; |
1343 | } |
1344 | |
1345 | |
1346 | Type *IndexedTy = GTI.getIndexedType(); |
1347 | if (!IndexedTy->isSized()) { |
1348 | Known.resetAll(); |
1349 | break; |
1350 | } |
1351 | |
1352 | unsigned IndexBitWidth = Index->getType()->getScalarSizeInBits(); |
1353 | KnownBits IndexBits(IndexBitWidth); |
1354 | computeKnownBits(Index, IndexBits, Depth + 1, Q); |
1355 | TypeSize IndexTypeSize = Q.DL.getTypeAllocSize(IndexedTy); |
1356 | uint64_t TypeSizeInBytes = IndexTypeSize.getKnownMinSize(); |
1357 | KnownBits ScalingFactor(IndexBitWidth); |
1358 | |
1359 | |
1360 | if (IndexTypeSize.isScalable()) { |
1361 | |
1362 | |
1363 | ScalingFactor.Zero.setLowBits(countTrailingZeros(TypeSizeInBytes)); |
1364 | } else if (IndexBits.isConstant()) { |
1365 | APInt IndexConst = IndexBits.getConstant(); |
1366 | APInt ScalingFactor(IndexBitWidth, TypeSizeInBytes); |
1367 | IndexConst *= ScalingFactor; |
1368 | AccConstIndices += IndexConst.sextOrTrunc(BitWidth); |
1369 | continue; |
1370 | } else { |
1371 | ScalingFactor = |
1372 | KnownBits::makeConstant(APInt(IndexBitWidth, TypeSizeInBytes)); |
1373 | } |
1374 | IndexBits = KnownBits::mul(IndexBits, ScalingFactor); |
1375 | |
1376 | |
1377 | |
1378 | |
1379 | IndexBits = IndexBits.sextOrTrunc(BitWidth); |
1380 | |
1381 | |
1382 | |
1383 | Known = KnownBits::computeForAddSub( |
1384 | true, false, Known, IndexBits); |
1385 | } |
1386 | if (!Known.isUnknown() && !AccConstIndices.isNullValue()) { |
1387 | KnownBits Index = KnownBits::makeConstant(AccConstIndices); |
1388 | Known = KnownBits::computeForAddSub( |
1389 | true, false, Known, Index); |
1390 | } |
1391 | break; |
1392 | } |
1393 | case Instruction::PHI: { |
1394 | const PHINode *P = cast<PHINode>(I); |
1395 | BinaryOperator *BO = nullptr; |
1396 | Value *R = nullptr, *L = nullptr; |
1397 | if (matchSimpleRecurrence(P, BO, R, L)) { |
1398 | |
1399 | |
1400 | |
1401 | unsigned Opcode = BO->getOpcode(); |
1402 | |
1403 | |
1404 | |
1405 | |
1406 | if ((Opcode == Instruction::LShr || Opcode == Instruction::AShr || |
1407 | Opcode == Instruction::Shl) && |
1408 | BO->getOperand(0) == I) { |
1409 | |
1410 | |
1411 | |
1412 | |
1413 | |
1414 | |
1415 | |
1416 | |
1417 | |
1418 | Query RecQ = Q; |
1419 | RecQ.CxtI = P; |
1420 | computeKnownBits(R, DemandedElts, Known2, Depth + 1, RecQ); |
1421 | switch (Opcode) { |
1422 | case Instruction::Shl: |
1423 | |
1424 | Known.Zero.setLowBits(Known2.countMinTrailingZeros()); |
1425 | break; |
1426 | case Instruction::LShr: |
1427 | |
1428 | |
1429 | Known.Zero.setHighBits(Known2.countMinLeadingZeros()); |
1430 | break; |
1431 | case Instruction::AShr: |
1432 | |
1433 | Known.Zero.setHighBits(Known2.countMinLeadingZeros()); |
1434 | Known.One.setHighBits(Known2.countMinLeadingOnes()); |
1435 | break; |
1436 | }; |
1437 | } |
1438 | |
1439 | |
1440 | |
1441 | |
1442 | if (Opcode == Instruction::Add || |
1443 | Opcode == Instruction::Sub || |
1444 | Opcode == Instruction::And || |
1445 | Opcode == Instruction::Or || |
1446 | Opcode == Instruction::Mul) { |
1447 | |
1448 | |
1449 | |
1450 | |
1451 | Query RecQ = Q; |
1452 | |
1453 | unsigned OpNum = P->getOperand(0) == R ? 0 : 1; |
1454 | Instruction *RInst = P->getIncomingBlock(OpNum)->getTerminator(); |
1455 | Instruction *LInst = P->getIncomingBlock(1-OpNum)->getTerminator(); |
1456 | |
1457 | |
1458 | |
1459 | RecQ.CxtI = RInst; |
1460 | computeKnownBits(R, Known2, Depth + 1, RecQ); |
1461 | |
1462 | |
1463 | KnownBits Known3(BitWidth); |
1464 | RecQ.CxtI = LInst; |
1465 | computeKnownBits(L, Known3, Depth + 1, RecQ); |
1466 | |
1467 | Known.Zero.setLowBits(std::min(Known2.countMinTrailingZeros(), |
1468 | Known3.countMinTrailingZeros())); |
1469 | |
1470 | auto *OverflowOp = dyn_cast<OverflowingBinaryOperator>(BO); |
1471 | if (OverflowOp && Q.IIQ.hasNoSignedWrap(OverflowOp)) { |
1472 | |
1473 | |
1474 | |
1475 | |
1476 | |
1477 | |
1478 | |
1479 | |
1480 | |
1481 | if (Opcode == Instruction::Add) { |
1482 | if (Known2.isNonNegative() && Known3.isNonNegative()) |
1483 | Known.makeNonNegative(); |
1484 | else if (Known2.isNegative() && Known3.isNegative()) |
1485 | Known.makeNegative(); |
1486 | } |
1487 | |
1488 | |
1489 | |
1490 | else if (Opcode == Instruction::Sub && BO->getOperand(0) == I) { |
1491 | if (Known2.isNonNegative() && Known3.isNegative()) |
1492 | Known.makeNonNegative(); |
1493 | else if (Known2.isNegative() && Known3.isNonNegative()) |
1494 | Known.makeNegative(); |
1495 | } |
1496 | |
1497 | |
1498 | else if (Opcode == Instruction::Mul && Known2.isNonNegative() && |
1499 | Known3.isNonNegative()) |
1500 | Known.makeNonNegative(); |
1501 | } |
1502 | |
1503 | break; |
1504 | } |
1505 | } |
1506 | |
1507 | |
1508 | if (P->getNumIncomingValues() == 0) |
1509 | break; |
1510 | |
1511 | |
1512 | |
1513 | if (Depth < MaxAnalysisRecursionDepth - 1 && !Known.Zero && !Known.One) { |
1514 | |
1515 | if (dyn_cast_or_null<UndefValue>(P->hasConstantValue())) |
1516 | break; |
1517 | |
1518 | Known.Zero.setAllBits(); |
1519 | Known.One.setAllBits(); |
1520 | for (unsigned u = 0, e = P->getNumIncomingValues(); u < e; ++u) { |
1521 | Value *IncValue = P->getIncomingValue(u); |
1522 | |
1523 | if (IncValue == P) continue; |
1524 | |
1525 | |
1526 | |
1527 | |
1528 | |
1529 | Query RecQ = Q; |
1530 | RecQ.CxtI = P->getIncomingBlock(u)->getTerminator(); |
1531 | |
1532 | Known2 = KnownBits(BitWidth); |
1533 | |
1534 | |
1535 | computeKnownBits(IncValue, Known2, MaxAnalysisRecursionDepth - 1, RecQ); |
1536 | Known = KnownBits::commonBits(Known, Known2); |
1537 | |
1538 | |
1539 | if (Known.isUnknown()) |
1540 | break; |
1541 | } |
1542 | } |
1543 | break; |
1544 | } |
1545 | case Instruction::Call: |
1546 | case Instruction::Invoke: |
1547 | |
1548 | |
1549 | |
1550 | if (MDNode *MD = |
1551 | Q.IIQ.getMetadata(cast<Instruction>(I), LLVMContext::MD_range)) |
1552 | computeKnownBitsFromRangeMetadata(*MD, Known); |
1553 | if (const Value *RV = cast<CallBase>(I)->getReturnedArgOperand()) { |
1554 | computeKnownBits(RV, Known2, Depth + 1, Q); |
1555 | Known.Zero |= Known2.Zero; |
1556 | Known.One |= Known2.One; |
1557 | } |
1558 | if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) { |
1559 | switch (II->getIntrinsicID()) { |
1560 | default: break; |
1561 | case Intrinsic::abs: { |
1562 | computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q); |
1563 | bool IntMinIsPoison = match(II->getArgOperand(1), m_One()); |
1564 | Known = Known2.abs(IntMinIsPoison); |
1565 | break; |
1566 | } |
1567 | case Intrinsic::bitreverse: |
1568 | computeKnownBits(I->getOperand(0), DemandedElts, Known2, Depth + 1, Q); |
1569 | Known.Zero |= Known2.Zero.reverseBits(); |
1570 | Known.One |= Known2.One.reverseBits(); |
1571 | break; |
1572 | case Intrinsic::bswap: |
1573 | computeKnownBits(I->getOperand(0), DemandedElts, Known2, Depth + 1, Q); |
1574 | Known.Zero |= Known2.Zero.byteSwap(); |
1575 | Known.One |= Known2.One.byteSwap(); |
1576 | break; |
1577 | case Intrinsic::ctlz: { |
1578 | computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q); |
1579 | |
1580 | unsigned PossibleLZ = Known2.countMaxLeadingZeros(); |
1581 | |
1582 | if (II->getArgOperand(1) == ConstantInt::getTrue(II->getContext())) |
1583 | PossibleLZ = std::min(PossibleLZ, BitWidth - 1); |
1584 | unsigned LowBits = Log2_32(PossibleLZ)+1; |
1585 | Known.Zero.setBitsFrom(LowBits); |
1586 | break; |
1587 | } |
1588 | case Intrinsic::cttz: { |
1589 | computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q); |
1590 | |
1591 | unsigned PossibleTZ = Known2.countMaxTrailingZeros(); |
1592 | |
1593 | if (II->getArgOperand(1) == ConstantInt::getTrue(II->getContext())) |
1594 | PossibleTZ = std::min(PossibleTZ, BitWidth - 1); |
1595 | unsigned LowBits = Log2_32(PossibleTZ)+1; |
1596 | Known.Zero.setBitsFrom(LowBits); |
1597 | break; |
1598 | } |
1599 | case Intrinsic::ctpop: { |
1600 | computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q); |
1601 | |
1602 | |
1603 | unsigned BitsPossiblySet = Known2.countMaxPopulation(); |
1604 | unsigned LowBits = Log2_32(BitsPossiblySet)+1; |
1605 | Known.Zero.setBitsFrom(LowBits); |
1606 | |
1607 | |
1608 | break; |
1609 | } |
1610 | case Intrinsic::fshr: |
1611 | case Intrinsic::fshl: { |
1612 | const APInt *SA; |
1613 | if (!match(I->getOperand(2), m_APInt(SA))) |
1614 | break; |
1615 | |
1616 | |
1617 | uint64_t ShiftAmt = SA->urem(BitWidth); |
1618 | if (II->getIntrinsicID() == Intrinsic::fshr) |
1619 | ShiftAmt = BitWidth - ShiftAmt; |
1620 | |
1621 | KnownBits Known3(BitWidth); |
1622 | computeKnownBits(I->getOperand(0), Known2, Depth + 1, Q); |
1623 | computeKnownBits(I->getOperand(1), Known3, Depth + 1, Q); |
1624 | |
1625 | Known.Zero = |
1626 | Known2.Zero.shl(ShiftAmt) | Known3.Zero.lshr(BitWidth - ShiftAmt); |
1627 | Known.One = |
1628 | Known2.One.shl(ShiftAmt) | Known3.One.lshr(BitWidth - ShiftAmt); |
1629 | break; |
1630 | } |
1631 | case Intrinsic::uadd_sat: |
1632 | case Intrinsic::usub_sat: { |
1633 | bool IsAdd = II->getIntrinsicID() == Intrinsic::uadd_sat; |
1634 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1635 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1636 | |
1637 | |
1638 | |
1639 | |
1640 | unsigned LeadingKnown; |
1641 | if (IsAdd) |
1642 | LeadingKnown = std::max(Known.countMinLeadingOnes(), |
1643 | Known2.countMinLeadingOnes()); |
1644 | else |
1645 | LeadingKnown = std::max(Known.countMinLeadingZeros(), |
1646 | Known2.countMinLeadingOnes()); |
1647 | |
1648 | Known = KnownBits::computeForAddSub( |
1649 | IsAdd, false, Known, Known2); |
1650 | |
1651 | |
1652 | |
1653 | if (IsAdd) { |
1654 | Known.One.setHighBits(LeadingKnown); |
1655 | Known.Zero.clearAllBits(); |
1656 | } else { |
1657 | Known.Zero.setHighBits(LeadingKnown); |
1658 | Known.One.clearAllBits(); |
1659 | } |
1660 | break; |
1661 | } |
1662 | case Intrinsic::umin: |
1663 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1664 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1665 | Known = KnownBits::umin(Known, Known2); |
1666 | break; |
1667 | case Intrinsic::umax: |
1668 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1669 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1670 | Known = KnownBits::umax(Known, Known2); |
1671 | break; |
1672 | case Intrinsic::smin: |
1673 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1674 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1675 | Known = KnownBits::smin(Known, Known2); |
1676 | break; |
1677 | case Intrinsic::smax: |
1678 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1679 | computeKnownBits(I->getOperand(1), Known2, Depth + 1, Q); |
1680 | Known = KnownBits::smax(Known, Known2); |
1681 | break; |
1682 | case Intrinsic::x86_sse42_crc32_64_64: |
1683 | Known.Zero.setBitsFrom(32); |
1684 | break; |
1685 | case Intrinsic::riscv_vsetvli: |
1686 | case Intrinsic::riscv_vsetvlimax: |
1687 | |
1688 | |
1689 | if (BitWidth >= 32) |
1690 | Known.Zero.setBitsFrom(31); |
1691 | break; |
1692 | } |
1693 | } |
1694 | break; |
1695 | case Instruction::ShuffleVector: { |
1696 | auto *Shuf = dyn_cast<ShuffleVectorInst>(I); |
1697 | |
1698 | if (!Shuf) { |
1699 | Known.resetAll(); |
1700 | return; |
1701 | } |
1702 | |
1703 | |
1704 | APInt DemandedLHS, DemandedRHS; |
1705 | if (!getShuffleDemandedElts(Shuf, DemandedElts, DemandedLHS, DemandedRHS)) { |
1706 | Known.resetAll(); |
1707 | return; |
1708 | } |
1709 | Known.One.setAllBits(); |
1710 | Known.Zero.setAllBits(); |
1711 | if (!!DemandedLHS) { |
1712 | const Value *LHS = Shuf->getOperand(0); |
1713 | computeKnownBits(LHS, DemandedLHS, Known, Depth + 1, Q); |
1714 | |
1715 | if (Known.isUnknown()) |
1716 | break; |
1717 | } |
1718 | if (!!DemandedRHS) { |
1719 | const Value *RHS = Shuf->getOperand(1); |
1720 | computeKnownBits(RHS, DemandedRHS, Known2, Depth + 1, Q); |
1721 | Known = KnownBits::commonBits(Known, Known2); |
1722 | } |
1723 | break; |
1724 | } |
1725 | case Instruction::InsertElement: { |
1726 | const Value *Vec = I->getOperand(0); |
1727 | const Value *Elt = I->getOperand(1); |
1728 | auto *CIdx = dyn_cast<ConstantInt>(I->getOperand(2)); |
1729 | |
1730 | unsigned NumElts = DemandedElts.getBitWidth(); |
1731 | if (!CIdx || CIdx->getValue().uge(NumElts)) { |
1732 | Known.resetAll(); |
1733 | return; |
1734 | } |
1735 | Known.One.setAllBits(); |
1736 | Known.Zero.setAllBits(); |
1737 | unsigned EltIdx = CIdx->getZExtValue(); |
1738 | |
1739 | if (DemandedElts[EltIdx]) { |
1740 | computeKnownBits(Elt, Known, Depth + 1, Q); |
1741 | |
1742 | if (Known.isUnknown()) |
1743 | break; |
1744 | } |
1745 | |
1746 | APInt DemandedVecElts = DemandedElts; |
1747 | DemandedVecElts.clearBit(EltIdx); |
1748 | if (!!DemandedVecElts) { |
1749 | computeKnownBits(Vec, DemandedVecElts, Known2, Depth + 1, Q); |
1750 | Known = KnownBits::commonBits(Known, Known2); |
1751 | } |
1752 | break; |
1753 | } |
1754 | case Instruction::ExtractElement: { |
1755 | |
1756 | |
1757 | const Value *Vec = I->getOperand(0); |
1758 | const Value *Idx = I->getOperand(1); |
1759 | auto *CIdx = dyn_cast<ConstantInt>(Idx); |
1760 | if (isa<ScalableVectorType>(Vec->getType())) { |
1761 | |
1762 | Known.resetAll(); |
1763 | break; |
1764 | } |
1765 | unsigned NumElts = cast<FixedVectorType>(Vec->getType())->getNumElements(); |
1766 | APInt DemandedVecElts = APInt::getAllOnesValue(NumElts); |
1767 | if (CIdx && CIdx->getValue().ult(NumElts)) |
1768 | DemandedVecElts = APInt::getOneBitSet(NumElts, CIdx->getZExtValue()); |
1769 | computeKnownBits(Vec, DemandedVecElts, Known, Depth + 1, Q); |
1770 | break; |
1771 | } |
1772 | case Instruction::ExtractValue: |
1773 | if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I->getOperand(0))) { |
1774 | const ExtractValueInst *EVI = cast<ExtractValueInst>(I); |
1775 | if (EVI->getNumIndices() != 1) break; |
1776 | if (EVI->getIndices()[0] == 0) { |
1777 | switch (II->getIntrinsicID()) { |
1778 | default: break; |
1779 | case Intrinsic::uadd_with_overflow: |
1780 | case Intrinsic::sadd_with_overflow: |
1781 | computeKnownBitsAddSub(true, II->getArgOperand(0), |
1782 | II->getArgOperand(1), false, DemandedElts, |
1783 | Known, Known2, Depth, Q); |
1784 | break; |
1785 | case Intrinsic::usub_with_overflow: |
1786 | case Intrinsic::ssub_with_overflow: |
1787 | computeKnownBitsAddSub(false, II->getArgOperand(0), |
1788 | II->getArgOperand(1), false, DemandedElts, |
1789 | Known, Known2, Depth, Q); |
1790 | break; |
1791 | case Intrinsic::umul_with_overflow: |
1792 | case Intrinsic::smul_with_overflow: |
1793 | computeKnownBitsMul(II->getArgOperand(0), II->getArgOperand(1), false, |
1794 | DemandedElts, Known, Known2, Depth, Q); |
1795 | break; |
1796 | } |
1797 | } |
1798 | } |
1799 | break; |
1800 | case Instruction::Freeze: |
1801 | if (isGuaranteedNotToBePoison(I->getOperand(0), Q.AC, Q.CxtI, Q.DT, |
1802 | Depth + 1)) |
1803 | computeKnownBits(I->getOperand(0), Known, Depth + 1, Q); |
1804 | break; |
1805 | } |
1806 | } |
1807 | |
1808 | |
1809 | |
1810 | KnownBits computeKnownBits(const Value *V, const APInt &DemandedElts, |
1811 | unsigned Depth, const Query &Q) { |
1812 | KnownBits Known(getBitWidth(V->getType(), Q.DL)); |
1813 | computeKnownBits(V, DemandedElts, Known, Depth, Q); |
1814 | return Known; |
1815 | } |
1816 | |
1817 | |
1818 | |
1819 | KnownBits computeKnownBits(const Value *V, unsigned Depth, const Query &Q) { |
1820 | KnownBits Known(getBitWidth(V->getType(), Q.DL)); |
1821 | computeKnownBits(V, Known, Depth, Q); |
1822 | return Known; |
1823 | } |
1824 | |
1825 | |
1826 | |
1827 | |
1828 | |
1829 | |
1830 | |
1831 | |
1832 | |
1833 | |
1834 | |
1835 | |
1836 | |
1837 | |
1838 | |
1839 | |
1840 | void computeKnownBits(const Value *V, const APInt &DemandedElts, |
1841 | KnownBits &Known, unsigned Depth, const Query &Q) { |
1842 | if (!DemandedElts || isa<ScalableVectorType>(V->getType())) { |
1843 | |
1844 | |
1845 | Known.resetAll(); |
1846 | return; |
1847 | } |
1848 | |
1849 | assert(V && "No Value?"); |
1850 | assert(Depth <= MaxAnalysisRecursionDepth && "Limit Search Depth"); |
1851 | |
1852 | #ifndef NDEBUG |
1853 | Type *Ty = V->getType(); |
1854 | unsigned BitWidth = Known.getBitWidth(); |
1855 | |
1856 | assert((Ty->isIntOrIntVectorTy(BitWidth) || Ty->isPtrOrPtrVectorTy()) && |
1857 | "Not integer or pointer type!"); |
1858 | |
1859 | if (auto *FVTy = dyn_cast<FixedVectorType>(Ty)) { |
1860 | assert( |
1861 | FVTy->getNumElements() == DemandedElts.getBitWidth() && |
1862 | "DemandedElt width should equal the fixed vector number of elements"); |
1863 | } else { |
1864 | assert(DemandedElts == APInt(1, 1) && |
1865 | "DemandedElt width should be 1 for scalars"); |
1866 | } |
1867 | |
1868 | Type *ScalarTy = Ty->getScalarType(); |
1869 | if (ScalarTy->isPointerTy()) { |
1870 | assert(BitWidth == Q.DL.getPointerTypeSizeInBits(ScalarTy) && |
1871 | "V and Known should have same BitWidth"); |
1872 | } else { |
1873 | assert(BitWidth == Q.DL.getTypeSizeInBits(ScalarTy) && |
1874 | "V and Known should have same BitWidth"); |
1875 | } |
1876 | #endif |
1877 | |
1878 | const APInt *C; |
1879 | if (match(V, m_APInt(C))) { |
1880 | |
1881 | Known = KnownBits::makeConstant(*C); |
1882 | return; |
1883 | } |
1884 | |
1885 | if (isa<ConstantPointerNull>(V) || isa<ConstantAggregateZero>(V)) { |
1886 | Known.setAllZero(); |
1887 | return; |
1888 | } |
1889 | |
1890 | |
1891 | if (const ConstantDataVector *CDV = dyn_cast<ConstantDataVector>(V)) { |
1892 | |
1893 | |
1894 | Known.Zero.setAllBits(); Known.One.setAllBits(); |
1895 | for (unsigned i = 0, e = CDV->getNumElements(); i != e; ++i) { |
1896 | if (!DemandedElts[i]) |
1897 | continue; |
1898 | APInt Elt = CDV->getElementAsAPInt(i); |
1899 | Known.Zero &= ~Elt; |
1900 | Known.One &= Elt; |
1901 | } |
1902 | return; |
1903 | } |
1904 | |
1905 | if (const auto *CV = dyn_cast<ConstantVector>(V)) { |
1906 | |
1907 | |
1908 | Known.Zero.setAllBits(); Known.One.setAllBits(); |
1909 | for (unsigned i = 0, e = CV->getNumOperands(); i != e; ++i) { |
1910 | if (!DemandedElts[i]) |
1911 | continue; |
1912 | Constant *Element = CV->getAggregateElement(i); |
1913 | auto *ElementCI = dyn_cast_or_null<ConstantInt>(Element); |
1914 | if (!ElementCI) { |
1915 | Known.resetAll(); |
1916 | return; |
1917 | } |
1918 | const APInt &Elt = ElementCI->getValue(); |
1919 | Known.Zero &= ~Elt; |
1920 | Known.One &= Elt; |
1921 | } |
1922 | return; |
1923 | } |
1924 | |
1925 | |
1926 | Known.resetAll(); |
1927 | |
1928 | |
1929 | if (isa<UndefValue>(V)) |
1930 | return; |
1931 | |
1932 | |
1933 | |
1934 | assert(!isa<ConstantData>(V) && "Unhandled constant data!"); |
1935 | |
1936 | |
1937 | if (Depth == MaxAnalysisRecursionDepth) |
1938 | return; |
1939 | |
1940 | |
1941 | |
1942 | if (const GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) { |
1943 | if (!GA->isInterposable()) |
1944 | computeKnownBits(GA->getAliasee(), Known, Depth + 1, Q); |
1945 | return; |
1946 | } |
1947 | |
1948 | if (const Operator *I = dyn_cast<Operator>(V)) |
1949 | computeKnownBitsFromOperator(I, DemandedElts, Known, Depth, Q); |
1950 | |
1951 | |
1952 | if (isa<PointerType>(V->getType())) { |
1953 | Align Alignment = V->getPointerAlignment(Q.DL); |
1954 | Known.Zero.setLowBits(Log2(Alignment)); |
1955 | } |
1956 | |
1957 | |
1958 | |
1959 | |
1960 | |
1961 | computeKnownBitsFromAssume(V, Known, Depth, Q); |
1962 | |
1963 | assert((Known.Zero & Known.One) == 0 && "Bits known to be one AND zero?"); |
1964 | } |
1965 | |
1966 | |
1967 | |
1968 | |
1969 | |
1970 | bool isKnownToBeAPowerOfTwo(const Value *V, bool OrZero, unsigned Depth, |
1971 | const Query &Q) { |
1972 | assert(Depth <= MaxAnalysisRecursionDepth && "Limit Search Depth"); |
1973 | |
1974 | |
1975 | if (OrZero && match(V, m_Power2OrZero())) |
1976 | return true; |
1977 | if (match(V, m_Power2())) |
1978 | return true; |
1979 | |
1980 | |
1981 | |
1982 | if (match(V, m_Shl(m_One(), m_Value()))) |
1983 | return true; |
1984 | |
1985 | |
1986 | |
1987 | if (match(V, m_LShr(m_SignMask(), m_Value()))) |
1988 | return true; |
1989 | |
1990 | |
1991 | if (Depth++ == MaxAnalysisRecursionDepth) |
1992 | return false; |
1993 | |
1994 | Value *X = nullptr, *Y = nullptr; |
1995 | |
1996 | |
1997 | if (OrZero && (match(V, m_Shl(m_Value(X), m_Value())) || |
1998 | match(V, m_LShr(m_Value(X), m_Value())))) |
1999 | return isKnownToBeAPowerOfTwo(X, true, Depth, Q); |
2000 | |
2001 | if (const ZExtInst *ZI = dyn_cast<ZExtInst>(V)) |
2002 | return isKnownToBeAPowerOfTwo(ZI->getOperand(0), OrZero, Depth, Q); |
2003 | |
2004 | if (const SelectInst *SI = dyn_cast<SelectInst>(V)) |
2005 | return isKnownToBeAPowerOfTwo(SI->getTrueValue(), OrZero, Depth, Q) && |
2006 | isKnownToBeAPowerOfTwo(SI->getFalseValue(), OrZero, Depth, Q); |
2007 | |
2008 | |
2009 | if (match(V, m_MaxOrMin(m_Value(X), m_Value(Y)))) { |
2010 | return isKnownToBeAPowerOfTwo(X, OrZero, Depth, Q) && |
2011 | isKnownToBeAPowerOfTwo(Y, OrZero, Depth, Q); |
2012 | } |
2013 | |
2014 | if (OrZero && match(V, m_And(m_Value(X), m_Value(Y)))) { |
2015 | |
2016 | if (isKnownToBeAPowerOfTwo(X, true, Depth, Q) || |
2017 | isKnownToBeAPowerOfTwo(Y, true, Depth, Q)) |
2018 | return true; |
2019 | |
2020 | if (match(X, m_Neg(m_Specific(Y))) || match(Y, m_Neg(m_Specific(X)))) |
2021 | return true; |
2022 | return false; |
2023 | } |
2024 | |
2025 | |
2026 | |
2027 | if (match(V, m_Add(m_Value(X), m_Value(Y)))) { |
2028 | const OverflowingBinaryOperator *VOBO = cast<OverflowingBinaryOperator>(V); |
2029 | if (OrZero || Q.IIQ.hasNoUnsignedWrap(VOBO) || |
2030 | Q.IIQ.hasNoSignedWrap(VOBO)) { |
2031 | if (match(X, m_And(m_Specific(Y), m_Value())) || |
2032 | match(X, m_And(m_Value(), m_Specific(Y)))) |
2033 | if (isKnownToBeAPowerOfTwo(Y, OrZero, Depth, Q)) |
2034 | return true; |
2035 | if (match(Y, m_And(m_Specific(X), m_Value())) || |
2036 | match(Y, m_And(m_Value(), m_Specific(X)))) |
2037 | if (isKnownToBeAPowerOfTwo(X, OrZero, Depth, Q)) |
2038 | return true; |
2039 | |
2040 | unsigned BitWidth = V->getType()->getScalarSizeInBits(); |
2041 | KnownBits LHSBits(BitWidth); |
2042 | computeKnownBits(X, LHSBits, Depth, Q); |
2043 | |
2044 | KnownBits RHSBits(BitWidth); |
2045 | computeKnownBits(Y, RHSBits, Depth, Q); |
2046 | |
2047 | |
2048 | |
2049 | if ((~(LHSBits.Zero & RHSBits.Zero)).isPowerOf2()) |
2050 | |
2051 | |
2052 | if (OrZero || RHSBits.One.getBoolValue() || LHSBits.One.getBoolValue()) |
2053 | return true; |
2054 | } |
2055 | } |
2056 | |
2057 | |
2058 | |
2059 | |
2060 | if (match(V, m_Exact(m_LShr(m_Value(), m_Value()))) || |
2061 | match(V, m_Exact(m_UDiv(m_Value(), m_Value())))) { |
2062 | return isKnownToBeAPowerOfTwo(cast<Operator>(V)->getOperand(0), OrZero, |
2063 | Depth, Q); |
2064 | } |
2065 | |
2066 | return false; |
2067 | } |
2068 | |
2069 | |
2070 | |
2071 | |
2072 | |
2073 | |
2074 | |
2075 | static bool isGEPKnownNonNull(const GEPOperator *GEP, unsigned Depth, |
2076 | const Query &Q) { |
2077 | const Function *F = nullptr; |
2078 | if (const Instruction *I = dyn_cast<Instruction>(GEP)) |
2079 | F = I->getFunction(); |
2080 | |
2081 | if (!GEP->isInBounds() || |
2082 | NullPointerIsDefined(F, GEP->getPointerAddressSpace())) |
2083 | return false; |
2084 | |
2085 | |
2086 | assert(GEP->getType()->isPointerTy() && "We only support plain pointer GEP"); |
2087 | |
2088 | |
2089 | |
2090 | if (isKnownNonZero(GEP->getPointerOperand(), Depth, Q)) |
2091 | return true; |
2092 | |
2093 | |
2094 | |
2095 | |
2096 | for (gep_type_iterator GTI = gep_type_begin(GEP), GTE = gep_type_end(GEP); |
2097 | GTI != GTE; ++GTI) { |
2098 | |
2099 | if (StructType *STy = GTI.getStructTypeOrNull()) { |
2100 | ConstantInt *OpC = cast<ConstantInt>(GTI.getOperand()); |
2101 | unsigned ElementIdx = OpC->getZExtValue(); |
2102 | const StructLayout *SL = Q.DL.getStructLayout(STy); |
2103 | uint64_t ElementOffset = SL->getElementOffset(ElementIdx); |
2104 | if (ElementOffset > 0) |
2105 | return true; |
2106 | continue; |
2107 | } |
2108 | |
2109 | |
2110 | if (Q.DL.getTypeAllocSize(GTI.getIndexedType()).getKnownMinSize() == 0) |
2111 | continue; |
2112 | |
2113 | |
2114 | |
2115 | if (ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand())) { |
2116 | if (!OpC->isZero()) |
2117 | return true; |
2118 | continue; |
2119 | } |
2120 | |
2121 | |
2122 | |
2123 | |
2124 | |
2125 | |
2126 | if (Depth++ >= MaxAnalysisRecursionDepth) |
2127 | continue; |
2128 | |
2129 | if (isKnownNonZero(GTI.getOperand(), Depth, Q)) |
2130 | return true; |
2131 | } |
2132 | |
2133 | return false; |
2134 | } |
2135 | |
2136 | static bool isKnownNonNullFromDominatingCondition(const Value *V, |
2137 | const Instruction *CtxI, |
2138 | const DominatorTree *DT) { |
2139 | if (isa<Constant>(V)) |
2140 | return false; |
2141 | |
2142 | if (!CtxI || !DT) |
2143 | return false; |
2144 | |
2145 | unsigned NumUsesExplored = 0; |
2146 | for (auto *U : V->users()) { |
2147 | |
2148 | if (NumUsesExplored >= DomConditionsMaxUses) |
2149 | break; |
2150 | NumUsesExplored++; |
2151 | |
2152 | |
2153 | |
2154 | if (const auto *CB = dyn_cast<CallBase>(U)) |
2155 | if (auto *CalledFunc = CB->getCalledFunction()) |
2156 | for (const Argument &Arg : CalledFunc->args()) |
2157 | if (CB->getArgOperand(Arg.getArgNo()) == V && |
2158 | Arg.hasNonNullAttr( false) && |
2159 | DT->dominates(CB, CtxI)) |
2160 | return true; |
2161 | |
2162 | |
2163 | if (V == getLoadStorePointerOperand(U)) { |
2164 | const Instruction *I = cast<Instruction>(U); |
2165 | if (!NullPointerIsDefined(I->getFunction(), |
2166 | V->getType()->getPointerAddressSpace()) && |
2167 | DT->dominates(I, CtxI)) |
2168 | return true; |
2169 | } |
2170 | |
2171 | |
2172 | Value *RHS; |
2173 | CmpInst::Predicate Pred; |
2174 | if (!match(U, m_c_ICmp(Pred, m_Specific(V), m_Value(RHS)))) |
2175 | continue; |
2176 | |
2177 | bool NonNullIfTrue; |
2178 | if (cmpExcludesZero(Pred, RHS)) |
2179 | NonNullIfTrue = true; |
2180 | else if (cmpExcludesZero(CmpInst::getInversePredicate(Pred), RHS)) |
2181 | NonNullIfTrue = false; |
2182 | else |
2183 | continue; |
2184 | |
2185 | SmallVector<const User *, 4> WorkList; |
2186 | SmallPtrSet<const User *, 4> Visited; |
2187 | for (auto *CmpU : U->users()) { |
2188 | assert(WorkList.empty() && "Should be!"); |
2189 | if (Visited.insert(CmpU).second) |
2190 | WorkList.push_back(CmpU); |
2191 | |
2192 | while (!WorkList.empty()) { |
2193 | auto *Curr = WorkList.pop_back_val(); |
2194 | |
2195 | |
2196 | |
2197 | |
2198 | |
2199 | if (NonNullIfTrue) |
2200 | if (match(Curr, m_LogicalAnd(m_Value(), m_Value()))) { |
2201 | for (auto *CurrU : Curr->users()) |
2202 | if (Visited.insert(CurrU).second) |
2203 | WorkList.push_back(CurrU); |
2204 | continue; |
2205 | } |
2206 | |
2207 | if (const BranchInst *BI = dyn_cast<BranchInst>(Curr)) { |
2208 | assert(BI->isConditional() && "uses a comparison!"); |
2209 | |
2210 | BasicBlock *NonNullSuccessor = |
2211 | BI->getSuccessor(NonNullIfTrue ? 0 : 1); |
2212 | BasicBlockEdge Edge(BI->getParent(), NonNullSuccessor); |
2213 | if (Edge.isSingleEdge() && DT->dominates(Edge, CtxI->getParent())) |
2214 | return true; |
2215 | } else if (NonNullIfTrue && isGuard(Curr) && |
2216 | DT->dominates(cast<Instruction>(Curr), CtxI)) { |
2217 | return true; |
2218 | } |
2219 | } |
2220 | } |
2221 | } |
2222 | |
2223 | return false; |
2224 | } |
2225 | |
2226 | |
2227 | |
2228 | |
2229 | static bool rangeMetadataExcludesValue(const MDNode* Ranges, const APInt& Value) { |
2230 | const unsigned NumRanges = Ranges->getNumOperands() / 2; |
2231 | assert(NumRanges >= 1); |
2232 | for (unsigned i = 0; i < NumRanges; ++i) { |
2233 | ConstantInt *Lower = |
2234 | mdconst::extract<ConstantInt>(Ranges->getOperand(2 * i + 0)); |
2235 | ConstantInt *Upper = |
2236 | mdconst::extract<ConstantInt>(Ranges->getOperand(2 * i + 1)); |
2237 | ConstantRange Range(Lower->getValue(), Upper->getValue()); |
2238 | if (Range.contains(Value)) |
2239 | return false; |
2240 | } |
2241 | return true; |
2242 | } |
2243 | |
2244 | |
2245 | |
2246 | static bool isNonZeroRecurrence(const PHINode *PN) { |
2247 | BinaryOperator *BO = nullptr; |
2248 | Value *Start = nullptr, *Step = nullptr; |
2249 | const APInt *StartC, *StepC; |
2250 | if (!matchSimpleRecurrence(PN, BO, Start, Step) || |
2251 | !match(Start, m_APInt(StartC)) || StartC->isNullValue()) |
2252 | return false; |
2253 | |
2254 | switch (BO->getOpcode()) { |
2255 | case Instruction::Add: |
2256 | |
2257 | |
2258 | return BO->hasNoUnsignedWrap() || |
2259 | (BO->hasNoSignedWrap() && match(Step, m_APInt(StepC)) && |
2260 | StartC->isNegative() == StepC->isNegative()); |
2261 | case Instruction::Mul: |
2262 | return (BO->hasNoUnsignedWrap() || BO->hasNoSignedWrap()) && |
2263 | match(Step, m_APInt(StepC)) && !StepC->isNullValue(); |
2264 | case Instruction::Shl: |
2265 | return BO->hasNoUnsignedWrap() || BO->hasNoSignedWrap(); |
2266 | case Instruction::AShr: |
2267 | case Instruction::LShr: |
2268 | return BO->isExact(); |
2269 | default: |
2270 | return false; |
2271 | } |
2272 | } |
2273 | |
2274 | |
2275 | |
2276 | |
2277 | |
2278 | |
2279 | |
2280 | bool isKnownNonZero(const Value *V, const APInt &DemandedElts, unsigned Depth, |
2281 | const Query &Q) { |
2282 | |
2283 | |
2284 | if (isa<ScalableVectorType>(V->getType())) |
2285 | return false; |
2286 | |
2287 | if (auto *C = dyn_cast<Constant>(V)) { |
2288 | if (C->isNullValue()) |
2289 | return false; |
2290 | if (isa<ConstantInt>(C)) |
2291 | |
2292 | return true; |
2293 | |
2294 | if (auto *CE = dyn_cast<ConstantExpr>(C)) { |
2295 | |
2296 | if (CE->getOpcode() == Instruction::IntToPtr || |
2297 | CE->getOpcode() == Instruction::PtrToInt) |
2298 | if (Q.DL.getTypeSizeInBits(CE->getOperand(0)->getType()) |
2299 | .getFixedSize() <= |
2300 | Q.DL.getTypeSizeInBits(CE->getType()).getFixedSize()) |
2301 | return isKnownNonZero(CE->getOperand(0), Depth, Q); |
2302 | } |
2303 | |
2304 | |
2305 | |
2306 | if (auto *VecTy = dyn_cast<FixedVectorType>(C->getType())) { |
2307 | for (unsigned i = 0, e = VecTy->getNumElements(); i != e; ++i) { |
2308 | if (!DemandedElts[i]) |
2309 | continue; |
2310 | Constant *Elt = C->getAggregateElement(i); |
2311 | if (!Elt || Elt->isNullValue()) |
2312 | return false; |
2313 | if (!isa<UndefValue>(Elt) && !isa<ConstantInt>(Elt)) |
2314 | return false; |
2315 | } |
2316 | return true; |
2317 | } |
2318 | |
2319 | |
2320 | |
2321 | |
2322 | if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) { |
2323 | if (!GV->isAbsoluteSymbolRef() && !GV->hasExternalWeakLinkage() && |
2324 | GV->getType()->getAddressSpace() == 0) |
2325 | return true; |
2326 | } else |
2327 | return false; |
2328 | } |
2329 | |
2330 | if (auto *I = dyn_cast<Instruction>(V)) { |
2331 | if (MDNode *Ranges = Q.IIQ.getMetadata(I, LLVMContext::MD_range)) { |
2332 | |
2333 | |
2334 | if (auto *Ty = dyn_cast<IntegerType>(V->getType())) { |
2335 | const APInt ZeroValue(Ty->getBitWidth(), 0); |
2336 | if (rangeMetadataExcludesValue(Ranges, ZeroValue)) |
2337 | return true; |
2338 | } |
2339 | } |
2340 | } |
2341 | |
2342 | if (isKnownNonZeroFromAssume(V, Q)) |
2343 | return true; |
2344 | |
2345 | |
2346 | if (Depth++ >= MaxAnalysisRecursionDepth) |
2347 | return false; |
2348 | |
2349 | |
2350 | |
2351 | if (PointerType *PtrTy = dyn_cast<PointerType>(V->getType())) { |
2352 | |
2353 | if (isa<AllocaInst>(V) && Q.DL.getAllocaAddrSpace() == 0) |
2354 | return true; |
2355 | |
2356 | |
2357 | |
2358 | if (const Argument *A = dyn_cast<Argument>(V)) { |
2359 | if (((A->hasPassPointeeByValueCopyAttr() && |
2360 | !NullPointerIsDefined(A->getParent(), PtrTy->getAddressSpace())) || |
2361 | A->hasNonNullAttr())) |
2362 | return true; |
2363 | } |
2364 | |
2365 | |
2366 | if (const LoadInst *LI = dyn_cast<LoadInst>(V)) |
2367 | if (Q.IIQ.getMetadata(LI, LLVMContext::MD_nonnull)) |
2368 | return true; |
2369 | |
2370 | if (const auto *Call = dyn_cast<CallBase>(V)) { |
2371 | if (Call->isReturnNonNull()) |
2372 | return true; |
2373 | if (const auto *RP = getArgumentAliasingToReturnedPointer(Call, true)) |
2374 | return isKnownNonZero(RP, Depth, Q); |
2375 | } |
2376 | } |
2377 | |
2378 | if (isKnownNonNullFromDominatingCondition(V, Q.CxtI, Q.DT)) |
2379 | return true; |
2380 | |
2381 | |
2382 | if (V->getType()->isPointerTy()) { |
2383 | |
2384 | |
2385 | |
2386 | |
2387 | |
2388 | |
2389 | |
2390 | if (const GEPOperator *GEP = dyn_cast<GEPOperator>(V)) |
2391 | return isGEPKnownNonNull(GEP, Depth, Q); |
2392 | |
2393 | if (auto *BCO = dyn_cast<BitCastOperator>(V)) |
2394 | return isKnownNonZero(BCO->getOperand(0), Depth, Q); |
2395 | |
2396 | if (auto *I2P = dyn_cast<IntToPtrInst>(V)) |
2397 | if (Q.DL.getTypeSizeInBits(I2P->getSrcTy()).getFixedSize() <= |
2398 | Q.DL.getTypeSizeInBits(I2P->getDestTy()).getFixedSize()) |
2399 | return isKnownNonZero(I2P->getOperand(0), Depth, Q); |
2400 | } |
2401 | |
2402 | |
2403 | |
2404 | if (auto *P2I = dyn_cast<PtrToIntInst>(V)) |
2405 | if (Q.DL.getTypeSizeInBits(P2I->getSrcTy()).getFixedSize() <= |
2406 | Q.DL.getTypeSizeInBits(P2I->getDestTy()).getFixedSize()) |
2407 | return isKnownNonZero(P2I->getOperand(0), Depth, Q); |
2408 | |
2409 | unsigned BitWidth = getBitWidth(V->getType()->getScalarType(), Q.DL); |
2410 | |
2411 | |
2412 | Value *X = nullptr, *Y = nullptr; |
2413 | if (match(V, m_Or(m_Value(X), m_Value(Y)))) |
2414 | return isKnownNonZero(X, DemandedElts, Depth, Q) || |
2415 | isKnownNonZero(Y, DemandedElts, Depth, Q); |
2416 | |
2417 | |
2418 | if (isa<SExtInst>(V) || isa<ZExtInst>(V)) |
2419 | return isKnownNonZero(cast<Instruction>(V)->getOperand(0), Depth, Q); |
2420 | |
2421 | |
2422 | |
2423 | if (match(V, m_Shl(m_Value(X), m_Value(Y)))) { |
2424 | |
2425 | const OverflowingBinaryOperator *BO = cast<OverflowingBinaryOperator>(V); |
2426 | if (Q.IIQ.hasNoUnsignedWrap(BO)) |
2427 | return isKnownNonZero(X, Depth, Q); |
2428 | |
2429 | KnownBits Known(BitWidth); |
2430 | computeKnownBits(X, DemandedElts, Known, Depth, Q); |
2431 | if (Known.One[0]) |
2432 | return true; |
2433 | } |
2434 | |
2435 | |
2436 | else if (match(V, m_Shr(m_Value(X), m_Value(Y)))) { |
2437 | |
2438 | const PossiblyExactOperator *BO = cast<PossiblyExactOperator>(V); |
2439 | if (BO->isExact()) |
2440 | return isKnownNonZero(X, Depth, Q); |
2441 | |
2442 | KnownBits Known = computeKnownBits(X, DemandedElts, Depth, Q); |
2443 | if (Known.isNegative()) |
2444 | return true; |
2445 | |
2446 | |
2447 | |
2448 | |
2449 | if (ConstantInt *Shift = dyn_cast<ConstantInt>(Y)) { |
2450 | auto ShiftVal = Shift->getLimitedValue(BitWidth - 1); |
2451 | |
2452 | if (Known.countMaxLeadingZeros() < BitWidth - ShiftVal) |
2453 | return true; |
2454 | |
2455 | if (Known.countMinTrailingZeros() >= ShiftVal) |
2456 | return isKnownNonZero(X, DemandedElts, Depth, Q); |
2457 | } |
2458 | } |
2459 | |
2460 | else if (match(V, m_Exact(m_IDiv(m_Value(X), m_Value())))) { |
2461 | return isKnownNonZero(X, DemandedElts, Depth, Q); |
2462 | } |
2463 | |
2464 | else if (match(V, m_Add(m_Value(X), m_Value(Y)))) { |
2465 | KnownBits XKnown = computeKnownBits(X, DemandedElts, Depth, Q); |
2466 | KnownBits YKnown = computeKnownBits(Y, DemandedElts, Depth, Q); |
2467 | |
2468 | |
2469 | |
2470 | if (XKnown.isNonNegative() && YKnown.isNonNegative()) |
2471 | if (isKnownNonZero(X, DemandedElts, Depth, Q) || |
2472 | isKnownNonZero(Y, DemandedElts, Depth, Q)) |
2473 | return true; |
2474 | |
2475 | |
2476 | |
2477 | if (XKnown.isNegative() && YKnown.isNegative()) { |
2478 | APInt Mask = APInt::getSignedMaxValue(BitWidth); |
2479 | |
2480 | |
2481 | if (XKnown.One.intersects(Mask)) |
2482 | return true; |
2483 | |
2484 | |
2485 | if (YKnown.One.intersects(Mask)) |
2486 | return true; |
2487 | } |
2488 | |
2489 | |
2490 | if (XKnown.isNonNegative() && |
2491 | isKnownToBeAPowerOfTwo(Y, false, Depth, Q)) |
2492 | return true; |
2493 | if (YKnown.isNonNegative() && |
2494 | isKnownToBeAPowerOfTwo(X, false, Depth, Q)) |
2495 | return true; |
2496 | } |
2497 | |
2498 | else if (match(V, m_Mul(m_Value(X), m_Value(Y)))) { |
2499 | const OverflowingBinaryOperator *BO = cast<OverflowingBinaryOperator>(V); |
2500 | |
2501 | |
2502 | if ((Q.IIQ.hasNoSignedWrap(BO) || Q.IIQ.hasNoUnsignedWrap(BO)) && |
2503 | isKnownNonZero(X, DemandedElts, Depth, Q) && |
2504 | isKnownNonZero(Y, DemandedElts, Depth, Q)) |
2505 | return true; |
2506 | } |
2507 | |
2508 | else if (const SelectInst *SI = dyn_cast<SelectInst>(V)) { |
2509 | if (isKnownNonZero(SI->getTrueValue(), DemandedElts, Depth, Q) && |
2510 | isKnownNonZero(SI->getFalseValue(), DemandedElts, Depth, Q)) |
2511 | return true; |
2512 | } |
2513 | |
2514 | else if (const PHINode *PN = dyn_cast<PHINode>(V)) { |
2515 | if (Q.IIQ.UseInstrInfo && isNonZeroRecurrence(PN)) |
2516 | return true; |
2517 | |
2518 | |
2519 | Query RecQ = Q; |
2520 | unsigned NewDepth = std::max(Depth, MaxAnalysisRecursionDepth - 1); |
2521 | return llvm::all_of(PN->operands(), [&](const Use &U) { |
2522 | if (U.get() == PN) |
2523 | return true; |
2524 | RecQ.CxtI = PN->getIncomingBlock(U)->getTerminator(); |
2525 | return isKnownNonZero(U.get(), DemandedElts, NewDepth, RecQ); |
2526 | }); |
2527 | } |
2528 | |
2529 | else if (const auto *EEI = dyn_cast<ExtractElementInst>(V)) { |
2530 | const Value *Vec = EEI->getVectorOperand(); |
2531 | const Value *Idx = EEI->getIndexOperand(); |
2532 | auto *CIdx = dyn_cast<ConstantInt>(Idx); |
2533 | if (auto *VecTy = dyn_cast<FixedVectorType>(Vec->getType())) { |
2534 | unsigned NumElts = VecTy->getNumElements(); |
2535 | APInt DemandedVecElts = APInt::getAllOnesValue(NumElts); |
2536 | if (CIdx && CIdx->getValue().ult(NumElts)) |
2537 | DemandedVecElts = APInt::getOneBitSet(NumElts, CIdx->getZExtValue()); |
2538 | return isKnownNonZero(Vec, DemandedVecElts, Depth, Q); |
2539 | } |
2540 | } |
2541 | |
2542 | else if (const FreezeInst *FI = dyn_cast<FreezeInst>(V)) { |
2543 | auto *Op = FI->getOperand(0); |
2544 | if (isKnownNonZero(Op, Depth, Q) && |
2545 | isGuaranteedNotToBePoison(Op, Q.AC, Q.CxtI, Q.DT, Depth)) |
2546 | return true; |
2547 | } |
2548 | |
2549 | KnownBits Known(BitWidth); |
2550 | computeKnownBits(V, DemandedElts, Known, Depth, Q); |
2551 | return Known.One != 0; |
2552 | } |
2553 | |
2554 | bool isKnownNonZero(const Value* V, unsigned Depth, const Query& Q) { |
2555 | |
2556 | |
2557 | if (isa<ScalableVectorType>(V->getType())) |
2558 | return false; |
2559 | |
2560 | auto *FVTy = dyn_cast<FixedVectorType>(V->getType()); |
2561 | APInt DemandedElts = |
2562 | FVTy ? APInt::getAllOnesValue(FVTy->getNumElements()) : APInt(1, 1); |
2563 | return isKnownNonZero(V, DemandedElts, Depth, Q); |
2564 | } |
2565 | |
2566 | |
2567 | |
2568 | |
2569 | |
2570 | |
2571 | |
2572 | static Optional<std::pair<Value*, Value*>> |
2573 | getInvertibleOperands(const Operator *Op1, |
2574 | const Operator *Op2) { |
2575 | if (Op1->getOpcode() != Op2->getOpcode()) |
2576 | return None; |
2577 | |
2578 | auto getOperands = [&](unsigned OpNum) -> auto { |
2579 | return std::make_pair(Op1->getOperand(OpNum), Op2->getOperand(OpNum)); |
2580 | }; |
2581 | |
2582 | switch (Op1->getOpcode()) { |
2583 | default: |
2584 | break; |
2585 | case Instruction::Add: |
2586 | case Instruction::Sub: |
2587 | if (Op1->getOperand(0) == Op2->getOperand(0)) |
2588 | return getOperands(1); |
2589 | if (Op1->getOperand(1) == Op2->getOperand(1)) |
2590 | return getOperands(0); |
2591 | break; |
2592 | case Instruction::Mul: { |
2593 | |
2594 | |
2595 | |
2596 | auto *OBO1 = cast<OverflowingBinaryOperator>(Op1); |
2597 | auto *OBO2 = cast<OverflowingBinaryOperator>(Op2); |
2598 | if ((!OBO1->hasNoUnsignedWrap() || !OBO2->hasNoUnsignedWrap()) && |
2599 | (!OBO1->hasNoSignedWrap() || !OBO2->hasNoSignedWrap())) |
2600 | break; |
2601 | |
2602 | |
2603 | if (Op1->getOperand(1) == Op2->getOperand(1) && |
2604 | isa<ConstantInt>(Op1->getOperand(1)) && |
2605 | !cast<ConstantInt>(Op1->getOperand(1))->isZero()) |
2606 | return getOperands(0); |
2607 | break; |
2608 | } |
2609 | case Instruction::Shl: { |
2610 | |
2611 | |
2612 | auto *OBO1 = cast<OverflowingBinaryOperator>(Op1); |
2613 | auto *OBO2 = cast<OverflowingBinaryOperator>(Op2); |
2614 | if ((!OBO1->hasNoUnsignedWrap() || !OBO2->hasNoUnsignedWrap()) && |
2615 | (!OBO1->hasNoSignedWrap() || !OBO2->hasNoSignedWrap())) |
2616 | break; |
2617 | |
2618 | if (Op1->getOperand(1) == Op2->getOperand(1)) |
2619 | return getOperands(0); |
2620 | break; |
2621 | } |
2622 | case Instruction::AShr: |
2623 | case Instruction::LShr: { |
2624 | auto *PEO1 = cast<PossiblyExactOperator>(Op1); |
2625 | auto *PEO2 = cast<PossiblyExactOperator>(Op2); |
2626 | if (!PEO1->isExact() || !PEO2->isExact()) |
2627 | break; |
2628 | |
2629 | if (Op1->getOperand(1) == Op2->getOperand(1)) |
2630 | return getOperands(0); |
2631 | break; |
2632 | } |
2633 | case Instruction::SExt: |
2634 | case Instruction::ZExt: |
2635 | if (Op1->getOperand(0)->getType() == Op2->getOperand(0)->getType()) |
2636 | return getOperands(0); |
2637 | break; |
2638 | case Instruction::PHI: { |
2639 | const PHINode *PN1 = cast<PHINode>(Op1); |
2640 | const PHINode *PN2 = cast<PHINode>(Op2); |
2641 | |
2642 | |
2643 | |
2644 | |
2645 | BinaryOperator *BO1 = nullptr; |
2646 | Value *Start1 = nullptr, *Step1 = nullptr; |
2647 | BinaryOperator *BO2 = nullptr; |
2648 | Value *Start2 = nullptr, *Step2 = nullptr; |
2649 | if (PN1->getParent() != PN2->getParent() || |
2650 | !matchSimpleRecurrence(PN1, BO1, Start1, Step1) || |
2651 | !matchSimpleRecurrence(PN2, BO2, Start2, Step2)) |
2652 | break; |
2653 | |
2654 | auto Values = getInvertibleOperands(cast<Operator>(BO1), |
2655 | cast<Operator>(BO2)); |
2656 | if (!Values) |
2657 | break; |
2658 | |
2659 | |
2660 | |
2661 | |
2662 | |
2663 | |
2664 | if (Values->first != PN1 || Values->second != PN2) |
2665 | break; |
2666 | |
2667 | return std::make_pair(Start1, Start2); |
2668 | } |
2669 | } |
2670 | return None; |
2671 | } |
2672 | |
2673 | |
2674 | static bool isAddOfNonZero(const Value *V1, const Value *V2, unsigned Depth, |
2675 | const Query &Q) { |
2676 | const BinaryOperator *BO = dyn_cast<BinaryOperator>(V1); |
2677 | if (!BO || BO->getOpcode() != Instruction::Add) |
2678 | return false; |
2679 | Value *Op = nullptr; |
2680 | if (V2 == BO->getOperand(0)) |
2681 | Op = BO->getOperand(1); |
2682 | else if (V2 == BO->getOperand(1)) |
2683 | Op = BO->getOperand(0); |
2684 | else |
2685 | return false; |
2686 | return isKnownNonZero(Op, Depth + 1, Q); |
2687 | } |
2688 | |
2689 | |
2690 | |
2691 | static bool isNonEqualMul(const Value *V1, const Value *V2, unsigned Depth, |
2692 | const Query &Q) { |
2693 | if (auto *OBO = dyn_cast<OverflowingBinaryOperator>(V2)) { |
2694 | const APInt *C; |
2695 | return match(OBO, m_Mul(m_Specific(V1), m_APInt(C))) && |
2696 | (OBO->hasNoUnsignedWrap() || OBO->hasNoSignedWrap()) && |
2697 | !C->isNullValue() && !C->isOneValue() && |
2698 | isKnownNonZero(V1, Depth + 1, Q); |
2699 | } |
2700 | return false; |
2701 | } |
2702 | |
2703 | |
2704 | |
2705 | static bool isNonEqualShl(const Value *V1, const Value *V2, unsigned Depth, |
2706 | const Query &Q) { |
2707 | if (auto *OBO = dyn_cast<OverflowingBinaryOperator>(V2)) { |
2708 | const APInt *C; |
2709 | return match(OBO, m_Shl(m_Specific(V1), m_APInt(C))) && |
2710 | (OBO->hasNoUnsignedWrap() || OBO->hasNoSignedWrap()) && |
2711 | !C->isNullValue() && isKnownNonZero(V1, Depth + 1, Q); |
2712 | } |
2713 | return false; |
2714 | } |
2715 | |
2716 | static bool isNonEqualPHIs(const PHINode *PN1, const PHINode *PN2, |
2717 | unsigned Depth, const Query &Q) { |
2718 | |
2719 | if (PN1->getParent() != PN2->getParent()) |
2720 | return false; |
2721 | |
2722 | SmallPtrSet<const BasicBlock *, 8> VisitedBBs; |
2723 | bool UsedFullRecursion = false; |
2724 | for (const BasicBlock *IncomBB : PN1->blocks()) { |
2725 | if (!VisitedBBs.insert(IncomBB).second) |
2726 | continue; |
2727 | const Value *IV1 = PN1->getIncomingValueForBlock(IncomBB); |
2728 | const Value *IV2 = PN2->getIncomingValueForBlock(IncomBB); |
2729 | const APInt *C1, *C2; |
2730 | if (match(IV1, m_APInt(C1)) && match(IV2, m_APInt(C2)) && *C1 != *C2) |
2731 | continue; |
2732 | |
2733 | |
2734 | if (UsedFullRecursion) |
2735 | return false; |
2736 | |
2737 | Query RecQ = Q; |
2738 | RecQ.CxtI = IncomBB->getTerminator(); |
2739 | if (!isKnownNonEqual(IV1, IV2, Depth + 1, RecQ)) |
2740 | return false; |
2741 | UsedFullRecursion = true; |
2742 | } |
2743 | return true; |
2744 | } |
2745 | |
2746 | |
2747 | static bool isKnownNonEqual(const Value *V1, const Value *V2, unsigned Depth, |
2748 | const Query &Q) { |
2749 | if (V1 == V2) |
2750 | return false; |
2751 | if (V1->getType() != V2->getType()) |
2752 | |
2753 | return false; |
2754 | |
2755 | if (Depth >= MaxAnalysisRecursionDepth) |
2756 | return false; |
2757 | |
2758 | |
2759 | |
2760 | |
2761 | auto *O1 = dyn_cast<Operator>(V1); |
2762 | auto *O2 = dyn_cast<Operator>(V2); |
2763 | if (O1 && O2 && O1->getOpcode() == O2->getOpcode()) { |
2764 | if (auto Values = getInvertibleOperands(O1, O2)) |
2765 | return isKnownNonEqual(Values->first, Values->second, Depth + 1, Q); |
2766 | |
2767 | if (const PHINode *PN1 = dyn_cast<PHINode>(V1)) { |
2768 | const PHINode *PN2 = cast<PHINode>(V2); |
2769 | |
2770 | |
2771 | if (isNonEqualPHIs(PN1, PN2, Depth, Q)) |
2772 | return true; |
2773 | }; |
2774 | } |
2775 | |
2776 | if (isAddOfNonZero(V1, V2, Depth, Q) || isAddOfNonZero(V2, V1, Depth, Q)) |
2777 | return true; |
2778 | |
2779 | if (isNonEqualMul(V1, V2, Depth, Q) || isNonEqualMul(V2, V1, Depth, Q)) |
2780 | return true; |
2781 | |
2782 | if (isNonEqualShl(V1, V2, Depth, Q) || isNonEqualShl(V2, V1, Depth, Q)) |
2783 | return true; |
2784 | |
2785 | if (V1->getType()->isIntOrIntVectorTy()) { |
2786 | |
2787 | |
2788 | KnownBits Known1 = computeKnownBits(V1, Depth, Q); |
2789 | KnownBits Known2 = computeKnownBits(V2, Depth, Q); |
2790 | |
2791 | if (Known1.Zero.intersects(Known2.One) || |
2792 | Known2.Zero.intersects(Known1.One)) |
2793 | return true; |
2794 | } |
2795 | return false; |
2796 | } |
2797 | |
2798 | |
2799 | |
2800 | |
2801 | |
2802 | |
2803 | |
2804 | |
2805 | |
2806 | |
2807 | bool MaskedValueIsZero(const Value *V, const APInt &Mask, unsigned Depth, |
2808 | const Query &Q) { |
2809 | KnownBits Known(Mask.getBitWidth()); |
2810 | computeKnownBits(V, Known, Depth, Q); |
2811 | return Mask.isSubsetOf(Known.Zero); |
2812 | } |
2813 | |
2814 | |
2815 | |
2816 | static bool isSignedMinMaxClamp(const Value *Select, const Value *&In, |
2817 | const APInt *&CLow, const APInt *&CHigh) { |
2818 | assert(isa<Operator>(Select) && |
2819 | cast<Operator>(Select)->getOpcode() == Instruction::Select && |
2820 | "Input should be a Select!"); |
2821 | |
2822 | const Value *LHS = nullptr, *RHS = nullptr; |
2823 | SelectPatternFlavor SPF = matchSelectPattern(Select, LHS, RHS).Flavor; |
2824 | if (SPF != SPF_SMAX && SPF != SPF_SMIN) |
2825 | return false; |
2826 | |
2827 | if (!match(RHS, m_APInt(CLow))) |
2828 | return false; |
2829 | |
2830 | const Value *LHS2 = nullptr, *RHS2 = nullptr; |
2831 | SelectPatternFlavor SPF2 = matchSelectPattern(LHS, LHS2, RHS2).Flavor; |
2832 | if (getInverseMinMaxFlavor(SPF) != SPF2) |
2833 | return false; |
2834 | |
2835 | if (!match(RHS2, m_APInt(CHigh))) |
2836 | return false; |
2837 | |
2838 | if (SPF == SPF_SMIN) |
2839 | std::swap(CLow, CHigh); |
2840 | |
2841 | In = LHS2; |
2842 | return CLow->sle(*CHigh); |
2843 | } |
2844 | |
2845 | |
2846 | |
2847 | |
2848 | |
2849 | static unsigned computeNumSignBitsVectorConstant(const Value *V, |
2850 | const APInt &DemandedElts, |
2851 | unsigned TyBits) { |
2852 | const auto *CV = dyn_cast<Constant>(V); |
2853 | if (!CV || !isa<FixedVectorType>(CV->getType())) |
2854 | return 0; |
2855 | |
2856 | unsigned MinSignBits = TyBits; |
2857 | unsigned NumElts = cast<FixedVectorType>(CV->getType())->getNumElements(); |
2858 | for (unsigned i = 0; i != NumElts; ++i) { |
2859 | if (!DemandedElts[i]) |
2860 | continue; |
2861 | |
2862 | auto *Elt = dyn_cast_or_null<ConstantInt>(CV->getAggregateElement(i)); |
2863 | if (!Elt) |
2864 | return 0; |
2865 | |
2866 | MinSignBits = std::min(MinSignBits, Elt->getValue().getNumSignBits()); |
2867 | } |
2868 | |
2869 | return MinSignBits; |
2870 | } |
2871 | |
2872 | static unsigned ComputeNumSignBitsImpl(const Value *V, |
2873 | const APInt &DemandedElts, |
2874 | unsigned Depth, const Query &Q); |
2875 | |
2876 | static unsigned ComputeNumSignBits(const Value *V, const APInt &DemandedElts, |
2877 | unsigned Depth, const Query &Q) { |
2878 | unsigned Result = ComputeNumSignBitsImpl(V, DemandedElts, Depth, Q); |
2879 | assert(Result > 0 && "At least one sign bit needs to be present!"); |
2880 | return Result; |
2881 | } |
2882 | |
2883 | |
2884 | |
2885 | |
2886 | |
2887 | |
2888 | |
2889 | |
2890 | static unsigned ComputeNumSignBitsImpl(const Value *V, |
2891 | const APInt &DemandedElts, |
2892 | unsigned Depth, const Query &Q) { |
2893 | Type *Ty = V->getType(); |
2894 | |
2895 | |
2896 | |
2897 | if (isa<ScalableVectorType>(Ty)) |
2898 | return 1; |
2899 | |
2900 | #ifndef NDEBUG |
2901 | assert(Depth <= MaxAnalysisRecursionDepth && "Limit Search Depth"); |
2902 | |
2903 | if (auto *FVTy = dyn_cast<FixedVectorType>(Ty)) { |
2904 | assert( |
2905 | FVTy->getNumElements() == DemandedElts.getBitWidth() && |
2906 | "DemandedElt width should equal the fixed vector number of elements"); |
2907 | } else { |
2908 | assert(DemandedElts == APInt(1, 1) && |
2909 | "DemandedElt width should be 1 for scalars"); |
2910 | } |
2911 | #endif |
2912 | |
2913 | |
2914 | |
2915 | |
2916 | |
2917 | Type *ScalarTy = Ty->getScalarType(); |
2918 | unsigned TyBits = ScalarTy->isPointerTy() ? |
2919 | Q.DL.getPointerTypeSizeInBits(ScalarTy) : |
2920 | Q.DL.getTypeSizeInBits(ScalarTy); |
2921 | |
2922 | unsigned Tmp, Tmp2; |
2923 | unsigned FirstAnswer = 1; |
2924 | |
2925 | |
2926 | |
2927 | |
2928 | if (Depth == MaxAnalysisRecursionDepth) |
2929 | return 1; |
2930 | |
2931 | if (auto *U = dyn_cast<Operator>(V)) { |
2932 | switch (Operator::getOpcode(V)) { |
2933 | default: break; |
2934 | case Instruction::SExt: |
2935 | Tmp = TyBits - U->getOperand(0)->getType()->getScalarSizeInBits(); |
2936 | return ComputeNumSignBits(U->getOperand(0), Depth + 1, Q) + Tmp; |
2937 | |
2938 | case Instruction::SDiv: { |
2939 | const APInt *Denominator; |
2940 | |
2941 | if (match(U->getOperand(1), m_APInt(Denominator))) { |
2942 | |
2943 | |
2944 | if (!Denominator->isStrictlyPositive()) |
2945 | break; |
2946 | |
2947 | |
2948 | unsigned NumBits = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
2949 | |
2950 | |
2951 | return std::min(TyBits, NumBits + Denominator->logBase2()); |
2952 | } |
2953 | break; |
2954 | } |
2955 | |
2956 | case Instruction::SRem: { |
2957 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
2958 | |
2959 | const APInt *Denominator; |
2960 | |
2961 | |
2962 | |
2963 | if (match(U->getOperand(1), m_APInt(Denominator))) { |
2964 | |
2965 | |
2966 | if (Denominator->isStrictlyPositive()) { |
2967 | |
2968 | |
2969 | |
2970 | |
2971 | |
2972 | |
2973 | |
2974 | |
2975 | |
2976 | |
2977 | |
2978 | |
2979 | |
2980 | unsigned ResBits = TyBits - Denominator->ceilLogBase2(); |
2981 | Tmp = std::max(Tmp, ResBits); |
2982 | } |
2983 | } |
2984 | return Tmp; |
2985 | } |
2986 | |
2987 | case Instruction::AShr: { |
2988 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
2989 | |
2990 | const APInt *ShAmt; |
2991 | if (match(U->getOperand(1), m_APInt(ShAmt))) { |
2992 | if (ShAmt->uge(TyBits)) |
2993 | break; |
2994 | unsigned ShAmtLimited = ShAmt->getZExtValue(); |
2995 | Tmp += ShAmtLimited; |
2996 | if (Tmp > TyBits) Tmp = TyBits; |
2997 | } |
2998 | return Tmp; |
2999 | } |
3000 | case Instruction::Shl: { |
3001 | const APInt *ShAmt; |
3002 | if (match(U->getOperand(1), m_APInt(ShAmt))) { |
3003 | |
3004 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3005 | if (ShAmt->uge(TyBits) || |
3006 | ShAmt->uge(Tmp)) break; |
3007 | Tmp2 = ShAmt->getZExtValue(); |
3008 | return Tmp - Tmp2; |
3009 | } |
3010 | break; |
3011 | } |
3012 | case Instruction::And: |
3013 | case Instruction::Or: |
3014 | case Instruction::Xor: |
3015 | |
3016 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3017 | if (Tmp != 1) { |
3018 | Tmp2 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q); |
3019 | FirstAnswer = std::min(Tmp, Tmp2); |
3020 | |
3021 | |
3022 | |
3023 | } |
3024 | break; |
3025 | |
3026 | case Instruction::Select: { |
3027 | |
3028 | |
3029 | const Value *X; |
3030 | const APInt *CLow, *CHigh; |
3031 | if (isSignedMinMaxClamp(U, X, CLow, CHigh)) |
3032 | return std::min(CLow->getNumSignBits(), CHigh->getNumSignBits()); |
3033 | |
3034 | Tmp = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q); |
3035 | if (Tmp == 1) break; |
3036 | Tmp2 = ComputeNumSignBits(U->getOperand(2), Depth + 1, Q); |
3037 | return std::min(Tmp, Tmp2); |
3038 | } |
3039 | |
3040 | case Instruction::Add: |
3041 | |
3042 | |
3043 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3044 | if (Tmp == 1) break; |
3045 | |
3046 | |
3047 | if (const auto *CRHS = dyn_cast<Constant>(U->getOperand(1))) |
3048 | if (CRHS->isAllOnesValue()) { |
3049 | KnownBits Known(TyBits); |
3050 | computeKnownBits(U->getOperand(0), Known, Depth + 1, Q); |
3051 | |
3052 | |
3053 | |
3054 | if ((Known.Zero | 1).isAllOnesValue()) |
3055 | return TyBits; |
3056 | |
3057 | |
3058 | |
3059 | if (Known.isNonNegative()) |
3060 | return Tmp; |
3061 | } |
3062 | |
3063 | Tmp2 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q); |
3064 | if (Tmp2 == 1) break; |
3065 | return std::min(Tmp, Tmp2) - 1; |
3066 | |
3067 | case Instruction::Sub: |
3068 | Tmp2 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q); |
3069 | if (Tmp2 == 1) break; |
3070 | |
3071 | |
3072 | if (const auto *CLHS = dyn_cast<Constant>(U->getOperand(0))) |
3073 | if (CLHS->isNullValue()) { |
3074 | KnownBits Known(TyBits); |
3075 | computeKnownBits(U->getOperand(1), Known, Depth + 1, Q); |
3076 | |
3077 | |
3078 | if ((Known.Zero | 1).isAllOnesValue()) |
3079 | return TyBits; |
3080 | |
3081 | |
3082 | |
3083 | |
3084 | if (Known.isNonNegative()) |
3085 | return Tmp2; |
3086 | |
3087 | |
3088 | } |
3089 | |
3090 | |
3091 | |
3092 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3093 | if (Tmp == 1) break; |
3094 | return std::min(Tmp, Tmp2) - 1; |
3095 | |
3096 | case Instruction::Mul: { |
3097 | |
3098 | |
3099 | unsigned SignBitsOp0 = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3100 | if (SignBitsOp0 == 1) break; |
3101 | unsigned SignBitsOp1 = ComputeNumSignBits(U->getOperand(1), Depth + 1, Q); |
3102 | if (SignBitsOp1 == 1) break; |
3103 | unsigned OutValidBits = |
3104 | (TyBits - SignBitsOp0 + 1) + (TyBits - SignBitsOp1 + 1); |
3105 | return OutValidBits > TyBits ? 1 : TyBits - OutValidBits + 1; |
3106 | } |
3107 | |
3108 | case Instruction::PHI: { |
3109 | const PHINode *PN = cast<PHINode>(U); |
3110 | unsigned NumIncomingValues = PN->getNumIncomingValues(); |
3111 | |
3112 | if (NumIncomingValues > 4) break; |
3113 | |
3114 | if (NumIncomingValues == 0) break; |
3115 | |
3116 | |
3117 | |
3118 | Query RecQ = Q; |
3119 | Tmp = TyBits; |
3120 | for (unsigned i = 0, e = NumIncomingValues; i != e; ++i) { |
3121 | if (Tmp == 1) return Tmp; |
3122 | RecQ.CxtI = PN->getIncomingBlock(i)->getTerminator(); |
3123 | Tmp = std::min( |
3124 | Tmp, ComputeNumSignBits(PN->getIncomingValue(i), Depth + 1, RecQ)); |
3125 | } |
3126 | return Tmp; |
3127 | } |
3128 | |
3129 | case Instruction::Trunc: |
3130 | |
3131 | |
3132 | break; |
3133 | |
3134 | case Instruction::ExtractElement: |
3135 | |
3136 | |
3137 | |
3138 | |
3139 | return ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3140 | |
3141 | case Instruction::ShuffleVector: { |
3142 | |
3143 | |
3144 | auto *Shuf = dyn_cast<ShuffleVectorInst>(U); |
3145 | if (!Shuf) { |
3146 | |
3147 | return 1; |
3148 | } |
3149 | APInt DemandedLHS, DemandedRHS; |
3150 | |
3151 | |
3152 | if (!getShuffleDemandedElts(Shuf, DemandedElts, DemandedLHS, DemandedRHS)) |
3153 | return 1; |
3154 | Tmp = std::numeric_limits<unsigned>::max(); |
3155 | if (!!DemandedLHS) { |
3156 | const Value *LHS = Shuf->getOperand(0); |
3157 | Tmp = ComputeNumSignBits(LHS, DemandedLHS, Depth + 1, Q); |
3158 | } |
3159 | |
3160 | |
3161 | if (Tmp == 1) |
3162 | break; |
3163 | if (!!DemandedRHS) { |
3164 | const Value *RHS = Shuf->getOperand(1); |
3165 | Tmp2 = ComputeNumSignBits(RHS, DemandedRHS, Depth + 1, Q); |
3166 | Tmp = std::min(Tmp, Tmp2); |
3167 | } |
3168 | |
3169 | |
3170 | if (Tmp == 1) |
3171 | break; |
3172 | assert(Tmp <= TyBits && "Failed to determine minimum sign bits"); |
3173 | return Tmp; |
3174 | } |
3175 | case Instruction::Call: { |
3176 | if (const auto *II = dyn_cast<IntrinsicInst>(U)) { |
3177 | switch (II->getIntrinsicID()) { |
3178 | default: break; |
3179 | case Intrinsic::abs: |
3180 | Tmp = ComputeNumSignBits(U->getOperand(0), Depth + 1, Q); |
3181 | if (Tmp == 1) break; |
3182 | |
3183 | |
3184 | return Tmp - 1; |
3185 | } |
3186 | } |
3187 | } |
3188 | } |
3189 | } |
3190 | |
3191 | |
3192 | |
3193 | |
3194 | |
3195 | |
3196 | if (unsigned VecSignBits = |
3197 | computeNumSignBitsVectorConstant(V, DemandedElts, TyBits)) |
3198 | return VecSignBits; |
3199 | |
3200 | KnownBits Known(TyBits); |
3201 | computeKnownBits(V, DemandedElts, Known, Depth, Q); |
3202 | |
3203 | |
3204 | |
3205 | return std::max(FirstAnswer, Known.countMinSignBits()); |
3206 | } |
3207 | |
3208 | |
3209 | |
3210 | |
3211 | |
3212 | bool llvm::ComputeMultiple(Value *V, unsigned Base, Value *&Multiple, |
3213 | bool LookThroughSExt, unsigned Depth) { |
3214 | assert(V && "No Value?"); |
3215 | assert(Depth <= MaxAnalysisRecursionDepth && "Limit Search Depth"); |
3216 | assert(V->getType()->isIntegerTy() && "Not integer or pointer type!"); |
3217 | |
3218 | Type *T = V->getType(); |
3219 | |
3220 | ConstantInt *CI = dyn_cast<ConstantInt>(V); |
3221 | |
3222 | if (Base == 0) |
3223 | return false; |
3224 | |
3225 | if (Base == 1) { |
3226 | Multiple = V; |
3227 | return true; |
3228 | } |
3229 | |
3230 | ConstantExpr *CO = dyn_cast<ConstantExpr>(V); |
3231 | Constant *BaseVal = ConstantInt::get(T, Base); |
3232 | if (CO && CO == BaseVal) { |
3233 | |
3234 | Multiple = ConstantInt::get(T, 1); |
3235 | return true; |
3236 | } |
3237 | |
3238 | if (CI && CI->getZExtValue() % Base == 0) { |
3239 | Multiple = ConstantInt::get(T, CI->getZExtValue() / Base); |
3240 | return true; |
3241 | } |
3242 | |
3243 | if (Depth == MaxAnalysisRecursionDepth) return false; |
3244 | |
3245 | Operator *I = dyn_cast<Operator>(V); |
3246 | if (!I) return false; |
3247 | |
3248 | switch (I->getOpcode()) { |
3249 | default: break; |
3250 | case Instruction::SExt: |
3251 | if (!LookThroughSExt) return false; |
3252 | |
3253 | LLVM_FALLTHROUGH; |
3254 | case Instruction::ZExt: |
3255 | return ComputeMultiple(I->getOperand(0), Base, Multiple, |
3256 | LookThroughSExt, Depth+1); |
3257 | case Instruction::Shl: |
3258 | case Instruction::Mul: { |
3259 | Value *Op0 = I->getOperand(0); |
3260 | Value *Op1 = I->getOperand(1); |
3261 | |
3262 | if (I->getOpcode() == Instruction::Shl) { |
3263 | ConstantInt *Op1CI = dyn_cast<ConstantInt>(Op1); |
3264 | if (!Op1CI) return false; |
3265 | |
3266 | APInt Op1Int = Op1CI->getValue(); |
3267 | uint64_t BitToSet = Op1Int.getLimitedValue(Op1Int.getBitWidth() - 1); |
3268 | APInt API(Op1Int.getBitWidth(), 0); |
3269 | API.setBit(BitToSet); |
3270 | Op1 = ConstantInt::get(V->getContext(), API); |
3271 | } |
3272 | |
3273 | Value *Mul0 = nullptr; |
3274 | if (ComputeMultiple(Op0, Base, Mul0, LookThroughSExt, Depth+1)) { |
3275 | if (Constant *Op1C = dyn_cast<Constant>(Op1)) |
3276 | if (Constant *MulC = dyn_cast<Constant>(Mul0)) { |
3277 | if (Op1C->getType()->getPrimitiveSizeInBits().getFixedSize() < |
3278 | MulC->getType()->getPrimitiveSizeInBits().getFixedSize()) |
3279 | Op1C = ConstantExpr::getZExt(Op1C, MulC->getType()); |
3280 | if (Op1C->getType()->getPrimitiveSizeInBits().getFixedSize() > |
3281 | MulC->getType()->getPrimitiveSizeInBits().getFixedSize()) |
3282 | MulC = ConstantExpr::getZExt(MulC, Op1C->getType()); |
3283 | |
3284 | |
3285 | Multiple = ConstantExpr::getMul(MulC, Op1C); |
3286 | return true; |
3287 | } |
3288 | |
3289 | if (ConstantInt *Mul0CI = dyn_cast<ConstantInt>(Mul0)) |
3290 | if (Mul0CI->getValue() == 1) { |
3291 | |
3292 | Multiple = Op1; |
3293 | return true; |
3294 | } |
3295 | } |
3296 | |
3297 | Value *Mul1 = nullptr; |
3298 | if (ComputeMultiple(Op1, Base, Mul1, LookThroughSExt, Depth+1)) { |
3299 | if (Constant *Op0C = dyn_cast<Constant>(Op0)) |
3300 | if (Constant *MulC = dyn_cast<Constant>(Mul1)) { |
3301 | if (Op0C->getType()->getPrimitiveSizeInBits().getFixedSize() < |
3302 | MulC->getType()->getPrimitiveSizeInBits().getFixedSize()) |
3303 | Op0C = ConstantExpr::getZExt(Op0C, MulC->getType()); |
3304 | if (Op0C->getType()->getPrimitiveSizeInBits().getFixedSize() > |
3305 | MulC->getType()->getPrimitiveSizeInBits().getFixedSize()) |
3306 | MulC = ConstantExpr::getZExt(MulC, Op0C->getType()); |
3307 | |
3308 | |
3309 | Multiple = ConstantExpr::getMul(MulC, Op0C); |
3310 | return true; |
3311 | } |
3312 | |
3313 | if (ConstantInt *Mul1CI = dyn_cast<ConstantInt>(Mul1)) |
3314 | if (Mul1CI->getValue() == 1) { |
3315 | |
3316 | Multiple = Op0; |
3317 | return true; |
3318 | } |
3319 | } |
3320 | } |
3321 | } |
3322 | |
3323 | |
3324 | return false; |
3325 | } |
3326 | |
3327 | Intrinsic::ID llvm::getIntrinsicForCallSite(const CallBase &CB, |
3328 | const TargetLibraryInfo *TLI) { |
3329 | const Function *F = CB.getCalledFunction(); |
3330 | if (!F) |
3331 | return Intrinsic::not_intrinsic; |
3332 | |
3333 | if (F->isIntrinsic()) |
3334 | return F->getIntrinsicID(); |
3335 | |
3336 | |
3337 | |
3338 | |
3339 | LibFunc Func; |
3340 | if (F->hasLocalLinkage() || !TLI || !TLI->getLibFunc(CB, Func) || |
3341 | !CB.onlyReadsMemory()) |
3342 | return Intrinsic::not_intrinsic; |
3343 | |
3344 | switch (Func) { |
3345 | default: |
3346 | break; |
3347 | case LibFunc_sin: |
3348 | case LibFunc_sinf: |
3349 | case LibFunc_sinl: |
3350 | return Intrinsic::sin; |
3351 | case LibFunc_cos: |
3352 | case LibFunc_cosf: |
3353 | case LibFunc_cosl: |
3354 | return Intrinsic::cos; |
3355 | case LibFunc_exp: |
3356 | case LibFunc_expf: |
3357 | case LibFunc_expl: |
3358 | return Intrinsic::exp; |
3359 | case LibFunc_exp2: |
3360 | case LibFunc_exp2f: |
3361 | case LibFunc_exp2l: |
3362 | return Intrinsic::exp2; |
3363 | case LibFunc_log: |
3364 | case LibFunc_logf: |
3365 | case LibFunc_logl: |
3366 | return Intrinsic::log; |
3367 | case LibFunc_log10: |
3368 | case LibFunc_log10f: |
3369 | case LibFunc_log10l: |
3370 | return Intrinsic::log10; |
3371 | case LibFunc_log2: |
3372 | case LibFunc_log2f: |
3373 | case LibFunc_log2l: |
3374 | return Intrinsic::log2; |
3375 | case LibFunc_fabs: |
3376 | case LibFunc_fabsf: |
3377 | case LibFunc_fabsl: |
3378 | return Intrinsic::fabs; |
3379 | case LibFunc_fmin: |
3380 | case LibFunc_fminf: |
3381 | case LibFunc_fminl: |
3382 | return Intrinsic::minnum; |
3383 | case LibFunc_fmax: |
3384 | case LibFunc_fmaxf: |
3385 | case LibFunc_fmaxl: |
3386 | return Intrinsic::maxnum; |
3387 | case LibFunc_copysign: |
3388 | case LibFunc_copysignf: |
3389 | case LibFunc_copysignl: |
3390 | return Intrinsic::copysign; |
3391 | case LibFunc_floor: |
3392 | case LibFunc_floorf: |
3393 | case LibFunc_floorl: |
3394 | return Intrinsic::floor; |
3395 | case LibFunc_ceil: |
3396 | case LibFunc_ceilf: |
3397 | case LibFunc_ceill: |
3398 | return Intrinsic::ceil; |
3399 | case LibFunc_trunc: |
3400 | case LibFunc_truncf: |
3401 | case LibFunc_truncl: |
3402 | return Intrinsic::trunc; |
3403 | case LibFunc_rint: |
3404 | case LibFunc_rintf: |
3405 | case LibFunc_rintl: |
3406 | return Intrinsic::rint; |
3407 | case LibFunc_nearbyint: |
3408 | case LibFunc_nearbyintf: |
3409 | case LibFunc_nearbyintl: |
3410 | return Intrinsic::nearbyint; |
3411 | case LibFunc_round: |
3412 | case LibFunc_roundf: |
3413 | case LibFunc_roundl: |
3414 | return Intrinsic::round; |
3415 | case LibFunc_roundeven: |
3416 | case LibFunc_roundevenf: |
3417 | case LibFunc_roundevenl: |
3418 | return Intrinsic::roundeven; |
3419 | case LibFunc_pow: |
3420 | case LibFunc_powf: |
3421 | case LibFunc_powl: |
3422 | return Intrinsic::pow; |
3423 | case LibFunc_sqrt: |
3424 | case LibFunc_sqrtf: |
3425 | case LibFunc_sqrtl: |
3426 | return Intrinsic::sqrt; |
3427 | } |
3428 | |
3429 | return Intrinsic::not_intrinsic; |
3430 | } |
3431 | |
3432 | |
3433 | |
3434 | |
3435 | |
3436 | |
3437 | |
3438 | |
3439 | |
3440 | bool llvm::CannotBeNegativeZero(const Value *V, const TargetLibraryInfo *TLI, |
3441 | unsigned Depth) { |
3442 | if (auto *CFP = dyn_cast<ConstantFP>(V)) |
3443 | return !CFP->getValueAPF().isNegZero(); |
3444 | |
3445 | if (Depth == MaxAnalysisRecursionDepth) |
3446 | return false; |
3447 | |
3448 | auto *Op = dyn_cast<Operator>(V); |
3449 | if (!Op) |
3450 | return false; |
3451 | |
3452 | |
3453 | if (match(Op, m_FAdd(m_Value(), m_PosZeroFP()))) |
3454 | return true; |
3455 | |
3456 | |
3457 | if (isa<SIToFPInst>(Op) || isa<UIToFPInst>(Op)) |
3458 | return true; |
3459 | |
3460 | if (auto *Call = dyn_cast<CallInst>(Op)) { |
3461 | Intrinsic::ID IID = getIntrinsicForCallSite(*Call, TLI); |
3462 | switch (IID) { |
3463 | default: |
3464 | break; |
3465 | |
3466 | case Intrinsic::sqrt: |
3467 | case Intrinsic::canonicalize: |
3468 | return CannotBeNegativeZero(Call->getArgOperand(0), TLI, Depth + 1); |
3469 | |
3470 | case Intrinsic::fabs: |
3471 | return true; |
3472 | } |
3473 | } |
3474 | |
3475 | return false; |
3476 | } |
3477 | |
3478 | |
3479 | |
3480 | |
3481 | static bool cannotBeOrderedLessThanZeroImpl(const Value *V, |
3482 | const TargetLibraryInfo *TLI, |
3483 | bool SignBitOnly, |
3484 | unsigned Depth) { |
3485 | |
3486 | |
3487 | |
3488 | |
3489 | |
3490 | if (const ConstantFP *CFP = dyn_cast<ConstantFP>(V)) { |
3491 | return !CFP->getValueAPF().isNegative() || |
3492 | (!SignBitOnly && CFP->getValueAPF().isZero()); |
3493 | } |
3494 | |
3495 | |
3496 | if (auto *CV = dyn_cast<Constant>(V)) { |
3497 | if (auto *CVFVTy = dyn_cast<FixedVectorType>(CV->getType())) { |
3498 | unsigned NumElts = CVFVTy->getNumElements(); |
3499 | for (unsigned i = 0; i != NumElts; ++i) { |
3500 | auto *CFP = dyn_cast_or_null<ConstantFP>(CV->getAggregateElement(i)); |
3501 | if (!CFP) |
3502 | return false; |
3503 | if (CFP->getValueAPF().isNegative() && |
3504 | (SignBitOnly || !CFP->getValueAPF().isZero())) |
3505 | return false; |
3506 | } |
3507 | |
3508 | |
3509 | return true; |
3510 | } |
3511 | } |
3512 | |
3513 | if (Depth == MaxAnalysisRecursionDepth) |
3514 | return false; |
3515 | |
3516 | const Operator *I = dyn_cast<Operator>(V); |
3517 | if (!I) |
3518 | return false; |
3519 | |
3520 | switch (I->getOpcode()) { |
3521 | default: |
3522 | break; |
3523 | |
3524 | case Instruction::UIToFP: |
3525 | return true; |
3526 | case Instruction::FMul: |
3527 | case Instruction::FDiv: |
3528 | |
3529 | |
3530 | if (I->getOperand(0) == I->getOperand(1) && |
3531 | (!SignBitOnly || cast<FPMathOperator>(I)->hasNoNaNs())) |
3532 | return true; |
3533 | |
3534 | LLVM_FALLTHROUGH; |
3535 | case Instruction::FAdd: |
3536 | case Instruction::FRem: |
3537 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly, |
3538 | Depth + 1) && |
3539 | cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly, |
3540 | Depth + 1); |
3541 | case Instruction::Select: |
3542 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly, |
3543 | Depth + 1) && |
3544 | cannotBeOrderedLessThanZeroImpl(I->getOperand(2), TLI, SignBitOnly, |
3545 | Depth + 1); |
3546 | case Instruction::FPExt: |
3547 | case Instruction::FPTrunc: |
3548 | |
3549 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly, |
3550 | Depth + 1); |
3551 | case Instruction::ExtractElement: |
3552 | |
3553 | |
3554 | |
3555 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly, |
3556 | Depth + 1); |
3557 | case Instruction::Call: |
3558 | const auto *CI = cast<CallInst>(I); |
3559 | Intrinsic::ID IID = getIntrinsicForCallSite(*CI, TLI); |
3560 | switch (IID) { |
3561 | default: |
3562 | break; |
3563 | case Intrinsic::maxnum: { |
3564 | Value *V0 = I->getOperand(0), *V1 = I->getOperand(1); |
3565 | auto isPositiveNum = [&](Value *V) { |
3566 | if (SignBitOnly) { |
3567 | |
3568 | |
3569 | |
3570 | const APFloat *C; |
3571 | return match(V, m_APFloat(C)) && |
3572 | *C > APFloat::getZero(C->getSemantics()); |
3573 | } |
3574 | |
3575 | |
3576 | |
3577 | return isKnownNeverNaN(V, TLI) && |
3578 | cannotBeOrderedLessThanZeroImpl(V, TLI, false, Depth + 1); |
3579 | }; |
3580 | |
3581 | |
3582 | |
3583 | return isPositiveNum(V0) || isPositiveNum(V1); |
3584 | } |
3585 | |
3586 | case Intrinsic::maximum: |
3587 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly, |
3588 | Depth + 1) || |
3589 | cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly, |
3590 | Depth + 1); |
3591 | case Intrinsic::minnum: |
3592 | case Intrinsic::minimum: |
3593 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly, |
3594 | Depth + 1) && |
3595 | cannotBeOrderedLessThanZeroImpl(I->getOperand(1), TLI, SignBitOnly, |
3596 | Depth + 1); |
3597 | case Intrinsic::exp: |
3598 | case Intrinsic::exp2: |
3599 | case Intrinsic::fabs: |
3600 | return true; |
3601 | |
3602 | case Intrinsic::sqrt: |
3603 | |
3604 | if (!SignBitOnly) |
3605 | return true; |
3606 | return CI->hasNoNaNs() && (CI->hasNoSignedZeros() || |
3607 | CannotBeNegativeZero(CI->getOperand(0), TLI)); |
3608 | |
3609 | case Intrinsic::powi: |
3610 | if (ConstantInt *Exponent = dyn_cast<ConstantInt>(I->getOperand(1))) { |
3611 | |
3612 | if (Exponent->getBitWidth() <= 64 && Exponent->getSExtValue() % 2u == 0) |
3613 | return true; |
3614 | } |
3615 | |
3616 | |
3617 | |
3618 | |
3619 | |
3620 | |
3621 | |
3622 | |
3623 | |
3624 | |
3625 | |
3626 | |
3627 | |
3628 | return cannotBeOrderedLessThanZeroImpl(I->getOperand(0), TLI, SignBitOnly, |
3629 | Depth + 1); |
3630 | |
3631 | case Intrinsic::fma: |
3632 | case Intrinsic::fmuladd: |
3633 | |
3634 | return I->getOperand(0) == I->getOperand(1) && |
3635 | (!SignBitOnly || cast<FPMathOperator>(I)->hasNoNaNs()) && |
3636 | cannotBeOrderedLessThanZeroImpl(I->getOperand(2), TLI, SignBitOnly, |
3637 | Depth + 1); |
3638 | } |
3639 | break; |
3640 | } |
3641 | return false; |
3642 | } |
3643 | |
3644 | bool llvm::CannotBeOrderedLessThanZero(const Value *V, |
3645 | const TargetLibraryInfo *TLI) { |
3646 | return cannotBeOrderedLessThanZeroImpl(V, TLI, false, 0); |
3647 | } |
3648 | |
3649 | bool llvm::SignBitMustBeZero(const Value *V, const TargetLibraryInfo *TLI) { |
3650 | return cannotBeOrderedLessThanZeroImpl(V, TLI, true, 0); |
3651 | } |
3652 | |
3653 | bool llvm::isKnownNeverInfinity(const Value *V, const TargetLibraryInfo *TLI, |
3654 | unsigned Depth) { |
3655 | assert(V->getType()->isFPOrFPVectorTy() && "Querying for Inf on non-FP type"); |
3656 | |
3657 | |
3658 | if (auto *FPMathOp = dyn_cast<FPMathOperator>(V)) |
3659 | if (FPMathOp->hasNoInfs()) |
3660 | return true; |
3661 | |
3662 | |
3663 | if (auto *CFP = dyn_cast<ConstantFP>(V)) |
3664 | return !CFP->isInfinity(); |
3665 | |
3666 | if (Depth == MaxAnalysisRecursionDepth) |
3667 | return false; |
3668 | |
3669 | if (auto *Inst = dyn_cast<Instruction>(V)) { |
3670 | switch (Inst->getOpcode()) { |
3671 | case Instruction::Select: { |
3672 | return isKnownNeverInfinity(Inst->getOperand(1), TLI, Depth + 1) && |
3673 | isKnownNeverInfinity(Inst->getOperand(2), TLI, Depth + 1); |
3674 | } |
3675 | case Instruction::SIToFP: |
3676 | case Instruction::UIToFP: { |
3677 | |
3678 | |
3679 | |
3680 | int IntSize = Inst->getOperand(0)->getType()->getScalarSizeInBits(); |
3681 | if (Inst->getOpcode() == Instruction::SIToFP) |
3682 | --IntSize; |
3683 | |
3684 | |
3685 | |
3686 | Type *FPTy = Inst->getType()->getScalarType(); |
3687 | return ilogb(APFloat::getLargest(FPTy->getFltSemantics())) >= IntSize; |
3688 | } |
3689 | default: |
3690 | break; |
3691 | } |
3692 | } |
3693 | |
3694 | |
3695 | auto *VFVTy = dyn_cast<FixedVectorType>(V->getType()); |
3696 | if (VFVTy && isa<Constant>(V)) { |
3697 | |
3698 | unsigned NumElts = VFVTy->getNumElements(); |
3699 | for (unsigned i = 0; i != NumElts; ++i) { |
3700 | Constant *Elt = cast<Constant>(V)->getAggregateElement(i); |
3701 | if (!Elt) |
3702 | return false; |
3703 | if (isa<UndefValue>(Elt)) |
3704 | continue; |
3705 | auto *CElt = dyn_cast<ConstantFP>(Elt); |
3706 | if (!CElt || CElt->isInfinity()) |
3707 | return false; |
3708 | } |
3709 | |
3710 | return true; |
3711 | } |
3712 | |
3713 | |
3714 | return false; |
3715 | } |
3716 | |
3717 | bool llvm::isKnownNeverNaN(const Value *V, const TargetLibraryInfo *TLI, |
3718 | unsigned Depth) { |
3719 | assert(V->getType()->isFPOrFPVectorTy() && "Querying for NaN on non-FP type"); |
3720 | |
3721 | |
3722 | if (auto *FPMathOp = dyn_cast<FPMathOperator>(V)) |
3723 | if (FPMathOp->hasNoNaNs()) |
3724 | return true; |
3725 | |
3726 | |
3727 | if (auto *CFP = dyn_cast<ConstantFP>(V)) |
3728 | return !CFP->isNaN(); |
3729 | |
3730 | if (Depth == MaxAnalysisRecursionDepth) |
3731 | return false; |
3732 | |
3733 | if (auto *Inst = dyn_cast<Instruction>(V)) { |
3734 | switch (Inst->getOpcode()) { |
3735 | case Instruction::FAdd: |
3736 | case Instruction::FSub: |
3737 | |
3738 | return isKnownNeverNaN(Inst->getOperand(0), TLI, Depth + 1) && |
3739 | isKnownNeverNaN(Inst->getOperand(1), TLI, Depth + 1) && |
3740 | (isKnownNeverInfinity(Inst->getOperand(0), TLI, Depth + 1) || |
3741 | isKnownNeverInfinity(Inst->getOperand(1), TLI, Depth + 1)); |
3742 | |
3743 | case Instruction::FMul: |
3744 | |
3745 | |
3746 | return isKnownNeverNaN(Inst->getOperand(0), TLI, Depth + 1) && |
3747 | isKnownNeverInfinity(Inst->getOperand(0), TLI, Depth + 1) && |
3748 | isKnownNeverNaN(Inst->getOperand(1), TLI, Depth + 1) && |
3749 | isKnownNeverInfinity(Inst->getOperand(1), TLI, Depth + 1); |
3750 | |
3751 | case Instruction::FDiv: |
3752 | case Instruction::FRem: |
3753 | |
3754 | return false; |
3755 | |
3756 | case Instruction::Select: { |
3757 | return isKnownNeverNaN(Inst->getOperand(1), TLI, Depth + 1) && |
3758 | isKnownNeverNaN(Inst->getOperand(2), TLI, Depth + 1); |
3759 | } |
3760 | case Instruction::SIToFP: |
3761 | case Instruction::UIToFP: |
3762 | return true; |
3763 | case Instruction::FPTrunc: |
3764 | case Instruction::FPExt: |
3765 | return isKnownNeverNaN(Inst->getOperand(0), TLI, Depth + 1); |
3766 | default: |
3767 | break; |
3768 | } |
3769 | } |
3770 | |
3771 | if (const auto *II = dyn_cast<IntrinsicInst>(V)) { |
3772 | switch (II->getIntrinsicID()) { |
3773 | case Intrinsic::canonicalize: |
3774 | case Intrinsic::fabs: |
3775 | case Intrinsic::copysign: |
3776 | case Intrinsic::exp: |
3777 | case Intrinsic::exp2: |
3778 | case Intrinsic::floor: |
3779 | case Intrinsic::ceil: |
3780 | case Intrinsic::trunc: |
3781 | case Intrinsic::rint: |
3782 | case Intrinsic::nearbyint: |
3783 | case Intrinsic::round: |
3784 | case Intrinsic::roundeven: |
3785 | return isKnownNeverNaN(II->getArgOperand(0), TLI, Depth + 1); |
3786 | case Intrinsic::sqrt: |
3787 | return isKnownNeverNaN(II->getArgOperand(0), TLI, Depth + 1) && |
3788 | CannotBeOrderedLessThanZero(II->getArgOperand(0), TLI); |
3789 | case Intrinsic::minnum: |
3790 | case Intrinsic::maxnum: |
3791 | |
3792 | return isKnownNeverNaN(II->getArgOperand(0), TLI, Depth + 1) || |
3793 | isKnownNeverNaN(II->getArgOperand(1), TLI, Depth + 1); |
3794 | default: |
3795 | return false; |
3796 | } |
3797 | } |
3798 | |
3799 | |
3800 | auto *VFVTy = dyn_cast<FixedVectorType>(V->getType()); |
3801 | if (VFVTy && isa<Constant>(V)) { |
3802 | |
3803 | unsigned NumElts = VFVTy->getNumElements(); |
3804 | for (unsigned i = 0; i != NumElts; ++i) { |
3805 | Constant *Elt = cast<Constant>(V)->getAggregateElement(i); |
3806 | if (!Elt) |
3807 | return false; |
3808 | if (isa<UndefValue>(Elt)) |
3809 | continue; |
3810 | auto *CElt = dyn_cast<ConstantFP>(Elt); |
3811 | if (!CElt || CElt->isNaN()) |
3812 | return false; |
3813 | } |
3814 | |
3815 | return true; |
3816 | } |
3817 | |
3818 | |
3819 | return false; |
3820 | } |
3821 | |
3822 | Value *llvm::isBytewiseValue(Value *V, const DataLayout &DL) { |
3823 | |
3824 | |
3825 | if (V->getType()->isIntegerTy(8)) |
3826 | return V; |
3827 | |
3828 | LLVMContext &Ctx = V->getContext(); |
3829 | |
3830 | |
3831 | auto *UndefInt8 = UndefValue::get(Type::getInt8Ty(Ctx)); |
3832 | if (isa<UndefValue>(V)) |
3833 | return UndefInt8; |
3834 | |
3835 | |
3836 | if (!DL.getTypeStoreSize(V->getType()).isNonZero()) |
3837 | return UndefInt8; |
3838 | |
3839 | Constant *C = dyn_cast<Constant>(V); |
3840 | if (!C) { |
3841 | |
3842 | |
3843 | |
3844 | |
3845 | |
3846 | |
3847 | return nullptr; |
3848 | } |
3849 | |
3850 | |
3851 | if (C->isNullValue()) |
3852 | return Constant::getNullValue(Type::getInt8Ty(Ctx)); |
3853 | |
3854 | |
3855 | |
3856 | if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) { |
3857 | Type *Ty = nullptr; |
3858 | if (CFP->getType()->isHalfTy()) |
3859 | Ty = Type::getInt16Ty(Ctx); |
3860 | else if (CFP->getType()->isFloatTy()) |
3861 | Ty = Type::getInt32Ty(Ctx); |
3862 | else if (CFP->getType()->isDoubleTy()) |
3863 | Ty = Type::getInt64Ty(Ctx); |
3864 | |
3865 | return Ty ? isBytewiseValue(ConstantExpr::getBitCast(CFP, Ty), DL) |
3866 | : nullptr; |
3867 | } |
3868 | |
3869 | |
3870 | if (ConstantInt *CI = dyn_cast<ConstantInt>(C)) { |
3871 | if (CI->getBitWidth() % 8 == 0) { |
3872 | assert(CI->getBitWidth() > 8 && "8 bits should be handled above!"); |
3873 | if (!CI->getValue().isSplat(8)) |
3874 | return nullptr; |
3875 | return ConstantInt::get(Ctx, CI->getValue().trunc(8)); |
3876 | } |
3877 | } |
3878 | |
3879 | if (auto *CE = dyn_cast<ConstantExpr>(C)) { |
3880 | if (CE->getOpcode() == Instruction::IntToPtr) { |
3881 | if (auto *PtrTy = dyn_cast<PointerType>(CE->getType())) { |
3882 | unsigned BitWidth = DL.getPointerSizeInBits(PtrTy->getAddressSpace()); |
3883 | return isBytewiseValue( |
3884 | ConstantExpr::getIntegerCast(CE->getOperand(0), |
3885 | Type::getIntNTy(Ctx, BitWidth), false), |
3886 | DL); |
3887 | } |
3888 | } |
3889 | } |
3890 | |
3891 | auto Merge = [&](Value *LHS, Value *RHS) -> Value * { |
3892 | if (LHS == RHS) |
3893 | return LHS; |
3894 | if (!LHS || !RHS) |
3895 | return nullptr; |
3896 | if (LHS == UndefInt8) |
3897 | return RHS; |
3898 | if (RHS == UndefInt8) |
3899 | return LHS; |
3900 | return nullptr; |
3901 | }; |
3902 | |
3903 | if (ConstantDataSequential *CA = dyn_cast<ConstantDataSequential>(C)) { |
3904 | Value *Val = UndefInt8; |
3905 | for (unsigned I = 0, E = CA->getNumElements(); I != E; ++I) |
3906 | if (!(Val = Merge(Val, isBytewiseValue(CA->getElementAsConstant(I), DL)))) |
3907 | return nullptr; |
3908 | return Val; |
3909 | } |
3910 | |
3911 | if (isa<ConstantAggregate>(C)) { |
3912 | Value *Val = UndefInt8; |
3913 | for (unsigned I = 0, E = C->getNumOperands(); I != E; ++I) |
3914 | if (!(Val = Merge(Val, isBytewiseValue(C->getOperand(I), DL)))) |
3915 | return nullptr; |
3916 | return Val; |
3917 | } |
3918 | |
3919 | |
3920 | return nullptr; |
3921 | } |
3922 | |
3923 | |
3924 | |
3925 | |
3926 | |
3927 | |
3928 | |
3929 | static Value *BuildSubAggregate(Value *From, Value* To, Type *IndexedType, |
3930 | SmallVectorImpl<unsigned> &Idxs, |
3931 | unsigned IdxSkip, |
3932 | Instruction *InsertBefore) { |
3933 | StructType *STy = dyn_cast<StructType>(IndexedType); |
3934 | if (STy) { |
3935 | |
3936 | Value *OrigTo = To; |
3937 | |
3938 | for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { |
3939 | |
3940 | Idxs.push_back(i); |
3941 | Value *PrevTo = To; |
3942 | To = BuildSubAggregate(From, To, STy->getElementType(i), Idxs, IdxSkip, |
3943 | InsertBefore); |
3944 | Idxs.pop_back(); |
3945 | if (!To) { |
3946 | |
3947 | while (PrevTo != OrigTo) { |
3948 | InsertValueInst* Del = cast<InsertValueInst>(PrevTo); |
3949 | PrevTo = Del->getAggregateOperand(); |
3950 | Del->eraseFromParent(); |
3951 | } |
3952 | |
3953 | break; |
3954 | } |
3955 | } |
3956 | |
3957 | if (To) |
3958 | return To; |
3959 | } |
3960 | |
3961 | |
3962 | |
3963 | |
3964 | |
3965 | |
3966 | Value *V = FindInsertedValue(From, Idxs); |
3967 | |
3968 | if (!V) |
3969 | return nullptr; |
3970 | |
3971 | |
3972 | return InsertValueInst::Create(To, V, makeArrayRef(Idxs).slice(IdxSkip), |
3973 | "tmp", InsertBefore); |
3974 | } |
3975 | |
3976 | |
3977 | |
3978 | |
3979 | |
3980 | |
3981 | |
3982 | |
3983 | |
3984 | |
3985 | |
3986 | |
3987 | |
3988 | static Value *BuildSubAggregate(Value *From, ArrayRef<unsigned> idx_range, |
3989 | Instruction *InsertBefore) { |
3990 | assert(InsertBefore && "Must have someplace to insert!"); |
3991 | Type *IndexedType = ExtractValueInst::getIndexedType(From->getType(), |
3992 | idx_range); |
3993 | Value *To = UndefValue::get(IndexedType); |
3994 | SmallVector<unsigned, 10> Idxs(idx_range.begin(), idx_range.end()); |
3995 | unsigned IdxSkip = Idxs.size(); |
3996 | |
3997 | return BuildSubAggregate(From, To, IndexedType, Idxs, IdxSkip, InsertBefore); |
3998 | } |
3999 | |
4000 | |
4001 | |
4002 | |
4003 | |
4004 | |
4005 | |
4006 | Value *llvm::FindInsertedValue(Value *V, ArrayRef<unsigned> idx_range, |
4007 | Instruction *InsertBefore) { |
4008 | |
4009 | |
4010 | if (idx_range.empty()) |
4011 | return V; |
4012 | |
4013 | assert((V->getType()->isStructTy() || V->getType()->isArrayTy()) && |
4014 | "Not looking at a struct or array?"); |
4015 | assert(ExtractValueInst::getIndexedType(V->getType(), idx_range) && |
4016 | "Invalid indices for type?"); |
4017 | |
4018 | if (Constant *C = dyn_cast<Constant>(V)) { |
4019 | C = C->getAggregateElement(idx_range[0]); |
4020 | if (!C) return nullptr; |
4021 | return FindInsertedValue(C, idx_range.slice(1), InsertBefore); |
4022 | } |
4023 | |
4024 | if (InsertValueInst *I = dyn_cast<InsertValueInst>(V)) { |
4025 | |
4026 | |
4027 | const unsigned *req_idx = idx_range.begin(); |
4028 | for (const unsigned *i = I->idx_begin(), *e = I->idx_end(); |
4029 | i != e; ++i, ++req_idx) { |
4030 | if (req_idx == idx_range.end()) { |
4031 | |
4032 | if (!InsertBefore) |
4033 | return nullptr; |
4034 | |
4035 | |
4036 | |
4037 | |
4038 | |
4039 | |
4040 | |
4041 | |
4042 | |
4043 | |
4044 | |
4045 | return BuildSubAggregate(V, makeArrayRef(idx_range.begin(), req_idx), |
4046 | InsertBefore); |
4047 | } |
4048 | |
4049 | |
4050 | |
4051 | |
4052 | if (*req_idx != *i) |
4053 | return FindInsertedValue(I->getAggregateOperand(), idx_range, |
4054 | InsertBefore); |
4055 | } |
4056 | |
4057 | |
4058 | |
4059 | return FindInsertedValue(I->getInsertedValueOperand(), |
4060 | makeArrayRef(req_idx, idx_range.end()), |
4061 | InsertBefore); |
4062 | } |
4063 | |
4064 | if (ExtractValueInst *I = dyn_cast<ExtractValueInst>(V)) { |
4065 | |
4066 | |
4067 | |
4068 | |
4069 | |
4070 | unsigned size = I->getNumIndices() + idx_range.size(); |
4071 | |
4072 | SmallVector<unsigned, 5> Idxs; |
4073 | Idxs.reserve(size); |
4074 | |
4075 | Idxs.append(I->idx_begin(), I->idx_end()); |
4076 | |
4077 | |
4078 | Idxs.append(idx_range.begin(), idx_range.end()); |
4079 | |
4080 | assert(Idxs.size() == size |
4081 | && "Number of indices added not correct?"); |
4082 | |
4083 | return FindInsertedValue(I->getAggregateOperand(), Idxs, InsertBefore); |
4084 | } |
4085 | |
4086 | |
4087 | return nullptr; |
4088 | } |
4089 | |
4090 | bool llvm::isGEPBasedOnPointerToString(const GEPOperator *GEP, |
4091 | unsigned CharSize) { |
4092 | |
4093 | if (GEP->getNumOperands() != 3) |
4094 | return false; |
4095 | |
4096 | |
4097 | |
4098 | ArrayType *AT = dyn_cast<ArrayType>(GEP->getSourceElementType()); |
4099 | if (!AT || !AT->getElementType()->isIntegerTy(CharSize)) |
4100 | return false; |
4101 | |
4102 | |
4103 | |
4104 | const ConstantInt *FirstIdx = dyn_cast<ConstantInt>(GEP->getOperand(1)); |
4105 | if (!FirstIdx || !FirstIdx->isZero()) |
4106 | return false; |
4107 | |
4108 | return true; |
4109 | } |
4110 | |
4111 | bool llvm::getConstantDataArrayInfo(const Value *V, |
4112 | ConstantDataArraySlice &Slice, |
4113 | unsigned ElementSize, uint64_t Offset) { |
4114 | assert(V); |
4115 | |
4116 | |
4117 | V = V->stripPointerCasts(); |
4118 | |
4119 | |
4120 | |
4121 | if (const GEPOperator *GEP = dyn_cast<GEPOperator>(V)) { |
4122 | |
4123 | |
4124 | if (!isGEPBasedOnPointerToString(GEP, ElementSize)) |
4125 | return false; |
4126 | |
4127 | |
4128 | |
4129 | |
4130 | uint64_t StartIdx = 0; |
4131 | if (const ConstantInt *CI = dyn_cast<ConstantInt>(GEP->getOperand(2))) |
4132 | StartIdx = CI->getZExtValue(); |
4133 | else |
4134 | return false; |
4135 | return getConstantDataArrayInfo(GEP->getOperand(0), Slice, ElementSize, |
4136 | StartIdx + Offset); |
4137 | } |
4138 | |
4139 | |
4140 | |
4141 | |
4142 | const GlobalVariable *GV = dyn_cast<GlobalVariable>(V); |
4143 | if (!GV || !GV->isConstant() || !GV->hasDefinitiveInitializer()) |
4144 | return false; |
4145 | |
4146 | const ConstantDataArray *Array; |
4147 | ArrayType *ArrayTy; |
4148 | if (GV->getInitializer()->isNullValue()) { |
4149 | Type *GVTy = GV->getValueType(); |
4150 | if ( (ArrayTy = dyn_cast<ArrayType>(GVTy)) ) { |
4151 | |
4152 | Array = nullptr; |
4153 | } else { |
4154 | const DataLayout &DL = GV->getParent()->getDataLayout(); |
4155 | uint64_t SizeInBytes = DL.getTypeStoreSize(GVTy).getFixedSize(); |
4156 | uint64_t Length = SizeInBytes / (ElementSize / 8); |
4157 | if (Length <= Offset) |
4158 | return false; |
4159 | |
4160 | Slice.Array = nullptr; |
4161 | Slice.Offset = 0; |
4162 | Slice.Length = Length - Offset; |
4163 | return true; |
4164 | } |
4165 | } else { |
4166 | |
4167 | Array = dyn_cast<ConstantDataArray>(GV->getInitializer()); |
4168 | if (!Array) |
4169 | return false; |
4170 | ArrayTy = Array->getType(); |
4171 | } |
4172 | if (!ArrayTy->getElementType()->isIntegerTy(ElementSize)) |
4173 | return false; |
4174 | |
4175 | uint64_t NumElts = ArrayTy->getArrayNumElements(); |
4176 | if (Offset > NumElts) |
4177 | return false; |
4178 | |
4179 | Slice.Array = Array; |
4180 | Slice.Offset = Offset; |
4181 | Slice.Length = NumElts - Offset; |
4182 | return true; |
4183 | } |
4184 | |
4185 | |
4186 | |
4187 | |
4188 | bool llvm::getConstantStringInfo(const Value *V, StringRef &Str, |
4189 | uint64_t Offset, bool TrimAtNul) { |
4190 | ConstantDataArraySlice Slice; |
4191 | if (!getConstantDataArrayInfo(V, Slice, 8, Offset)) |
4192 | return false; |
4193 | |
4194 | if (Slice.Array == nullptr) { |
4195 | if (TrimAtNul) { |
4196 | Str = StringRef(); |
4197 | return true; |
4198 | } |
4199 | if (Slice.Length == 1) { |
4200 | Str = StringRef("", 1); |
4201 | return true; |
4202 | } |
4203 | |
4204 | |
4205 | return false; |
4206 | } |
4207 | |
4208 | |
4209 | Str = Slice.Array->getAsString(); |
4210 | |
4211 | Str = Str.substr(Slice.Offset); |
4212 | |
4213 | if (TrimAtNul) { |
4214 | |
4215 | |
4216 | |
4217 | Str = Str.substr(0, Str.find('\0')); |
4218 | } |
4219 | return true; |
4220 | } |
4221 | |
4222 | |
4223 | |
4224 | |
4225 | |
4226 | |
4227 | |
4228 | static uint64_t GetStringLengthH(const Value *V, |
4229 | SmallPtrSetImpl<const PHINode*> &PHIs, |
4230 | unsigned CharSize) { |
4231 | |
4232 | V = V->stripPointerCasts(); |
4233 | |
4234 | |
4235 | |
4236 | if (const PHINode *PN = dyn_cast<PHINode>(V)) { |
4237 | if (!PHIs.insert(PN).second) |
4238 | return ~0ULL; |
4239 | |
4240 | |
4241 | uint64_t LenSoFar = ~0ULL; |
4242 | for (Value *IncValue : PN->incoming_values()) { |
4243 | uint64_t Len = GetStringLengthH(IncValue, PHIs, CharSize); |
4244 | if (Len == 0) return 0; |
4245 | |
4246 | if (Len == ~0ULL) continue; |
4247 | |
4248 | if (Len != LenSoFar && LenSoFar != ~0ULL) |
4249 | return 0; |
4250 | LenSoFar = Len; |
4251 | } |
4252 | |
4253 | |
4254 | return LenSoFar; |
4255 | } |
4256 | |
4257 | |
4258 | if (const SelectInst *SI = dyn_cast<SelectInst>(V)) { |
4259 | uint64_t Len1 = GetStringLengthH(SI->getTrueValue(), PHIs, CharSize); |
4260 | if (Len1 == 0) return 0; |
4261 | uint64_t Len2 = GetStringLengthH(SI->getFalseValue(), PHIs, CharSize); |
4262 | if (Len2 == 0) return 0; |
4263 | if (Len1 == ~0ULL) return Len2; |
4264 | if (Len2 == ~0ULL) return Len1; |
4265 | if (Len1 != Len2) return 0; |
4266 | return Len1; |
4267 | } |
4268 | |
4269 | |
4270 | ConstantDataArraySlice Slice; |
4271 | if (!getConstantDataArrayInfo(V, Slice, CharSize)) |
4272 | return 0; |
4273 | |
4274 | if (Slice.Array == nullptr) |
4275 | return 1; |
4276 | |
4277 | |
4278 | unsigned NullIndex = 0; |
4279 | for (unsigned E = Slice.Length; NullIndex < E; ++NullIndex) { |
4280 | if (Slice.Array->getElementAsInteger(Slice.Offset + NullIndex) == 0) |
4281 | break; |
4282 | } |
4283 | |
4284 | return NullIndex + 1; |
4285 | } |
4286 | |
4287 | |
4288 | |
4289 | uint64_t llvm::GetStringLength(const Value *V, unsigned CharSize) { |
4290 | if (!V->getType()->isPointerTy()) |
4291 | return 0; |
4292 | |
4293 | SmallPtrSet<const PHINode*, 32> PHIs; |
4294 | uint64_t Len = GetStringLengthH(V, PHIs, CharSize); |
4295 | |
4296 | |
4297 | return Len == ~0ULL ? 1 : Len; |
4298 | } |
4299 | |
4300 | const Value * |
4301 | llvm::getArgumentAliasingToReturnedPointer(const CallBase *Call, |
4302 | bool MustPreserveNullness) { |
4303 | assert(Call && |
4304 | "getArgumentAliasingToReturnedPointer only works on nonnull calls"); |
4305 | if (const Value *RV = Call->getReturnedArgOperand()) |
4306 | return RV; |
4307 | |
4308 | if (isIntrinsicReturningPointerAliasingArgumentWithoutCapturing( |
4309 | Call, MustPreserveNullness)) |
4310 | return Call->getArgOperand(0); |
4311 | return nullptr; |
4312 | } |
4313 | |
4314 | bool llvm::isIntrinsicReturningPointerAliasingArgumentWithoutCapturing( |
4315 | const CallBase *Call, bool MustPreserveNullness) { |
4316 | switch (Call->getIntrinsicID()) { |
4317 | case Intrinsic::launder_invariant_group: |
4318 | case Intrinsic::strip_invariant_group: |
4319 | case Intrinsic::aarch64_irg: |
4320 | case Intrinsic::aarch64_tagp: |
4321 | return true; |
4322 | case Intrinsic::ptrmask: |
4323 | return !MustPreserveNullness; |
4324 | default: |
4325 | return false; |
4326 | } |
4327 | } |
4328 | |
4329 | |
4330 | |
4331 | static bool isSameUnderlyingObjectInLoop(const PHINode *PN, |
4332 | const LoopInfo *LI) { |
4333 | |
4334 | Loop *L = LI->getLoopFor(PN->getParent()); |
4335 | if (PN->getNumIncomingValues() != 2) |
4336 | return true; |
4337 | |
4338 | |
4339 | auto *PrevValue = dyn_cast<Instruction>(PN->getIncomingValue(0)); |
4340 | if (!PrevValue || LI->getLoopFor(PrevValue->getParent()) != L) |
4341 | PrevValue = dyn_cast<Instruction>(PN->getIncomingValue(1)); |
4342 | if (!PrevValue || LI->getLoopFor(PrevValue->getParent()) != L) |
4343 | return true; |
4344 | |
4345 | |
4346 | |
4347 | |
4348 | |
4349 | |
4350 | if (auto *Load = dyn_cast<LoadInst>(PrevValue)) |
4351 | if (!L->isLoopInvariant(Load->getPointerOperand())) |
4352 | return false; |
4353 | return true; |
4354 | } |
4355 | |
4356 | const Value *llvm::getUnderlyingObject(const Value *V, unsigned MaxLookup) { |
4357 | if (!V->getType()->isPointerTy()) |
4358 | return V; |
4359 | for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) { |
4360 | if (auto *GEP = dyn_cast<GEPOperator>(V)) { |
4361 | V = GEP->getPointerOperand(); |
4362 | } else if (Operator::getOpcode(V) == Instruction::BitCast || |
4363 | Operator::getOpcode(V) == Instruction::AddrSpaceCast) { |
4364 | V = cast<Operator>(V)->getOperand(0); |
4365 | if (!V->getType()->isPointerTy()) |
4366 | return V; |
4367 | } else if (auto *GA = dyn_cast<GlobalAlias>(V)) { |
4368 | if (GA->isInterposable()) |
4369 | return V; |
4370 | V = GA->getAliasee(); |
4371 | } else { |
4372 | if (auto *PHI = dyn_cast<PHINode>(V)) { |
4373 | |
4374 | if (PHI->getNumIncomingValues() == 1) { |
4375 | V = PHI->getIncomingValue(0); |
4376 | continue; |
4377 | } |
4378 | } else if (auto *Call = dyn_cast<CallBase>(V)) { |
4379 | |
4380 | |
4381 | |
4382 | |
4383 | |
4384 | |
4385 | |
4386 | |
4387 | |
4388 | if (auto *RP = getArgumentAliasingToReturnedPointer(Call, false)) { |
4389 | V = RP; |
4390 | continue; |
4391 | } |
4392 | } |
4393 | |
4394 | return V; |
4395 | } |
4396 | assert(V->getType()->isPointerTy() && "Unexpected operand type!"); |
4397 | } |
4398 | return V; |
4399 | } |
4400 | |
4401 | void llvm::getUnderlyingObjects(const Value *V, |
4402 | SmallVectorImpl<const Value *> &Objects, |
4403 | LoopInfo *LI, unsigned MaxLookup) { |
4404 | SmallPtrSet<const Value *, 4> Visited; |
4405 | SmallVector<const Value *, 4> Worklist; |
4406 | Worklist.push_back(V); |
4407 | do { |
4408 | const Value *P = Worklist.pop_back_val(); |
4409 | P = getUnderlyingObject(P, MaxLookup); |
4410 | |
4411 | if (!Visited.insert(P).second) |
4412 | continue; |
4413 | |
4414 | if (auto *SI = dyn_cast<SelectInst>(P)) { |
4415 | Worklist.push_back(SI->getTrueValue()); |
4416 | Worklist.push_back(SI->getFalseValue()); |
4417 | continue; |
4418 | } |
4419 | |
4420 | if (auto *PN = dyn_cast<PHINode>(P)) { |
4421 | |
4422 | |
4423 | |
4424 | |
4425 | |
4426 | |
4427 | |
4428 | |
4429 | |
4430 | |
4431 | if (!LI || !LI->isLoopHeader(PN->getParent()) || |
4432 | isSameUnderlyingObjectInLoop(PN, LI)) |
4433 | append_range(Worklist, PN->incoming_values()); |
4434 | continue; |
4435 | } |
4436 | |
4437 | Objects.push_back(P); |
4438 | } while (!Worklist.empty()); |
4439 | } |
4440 | |
4441 | |
4442 | |
4443 | static const Value *getUnderlyingObjectFromInt(const Value *V) { |
4444 | do { |
4445 | if (const Operator *U = dyn_cast<Operator>(V)) { |
4446 | |
4447 | |
4448 | if (U->getOpcode() == Instruction::PtrToInt) |
4449 | return U->getOperand(0); |
4450 | |
4451 | |
4452 | |
4453 | |
4454 | |
4455 | |
4456 | if (U->getOpcode() != Instruction::Add || |
4457 | (!isa<ConstantInt>(U->getOperand(1)) && |
4458 | Operator::getOpcode(U->getOperand(1)) != Instruction::Mul && |
4459 | !isa<PHINode>(U->getOperand(1)))) |
4460 | return V; |
4461 | V = U->getOperand(0); |
4462 | } else { |
4463 | return V; |
4464 | } |
4465 | assert(V->getType()->isIntegerTy() && "Unexpected operand type!"); |
4466 | } while (true); |
4467 | } |
4468 | |
4469 | |
4470 | |
4471 | |
4472 | bool llvm::getUnderlyingObjectsForCodeGen(const Value *V, |
4473 | SmallVectorImpl<Value *> &Objects) { |
4474 | SmallPtrSet<const Value *, 16> Visited; |
4475 | SmallVector<const Value *, 4> Working(1, V); |
4476 | do { |
4477 | V = Working.pop_back_val(); |
4478 | |
4479 | SmallVector<const Value *, 4> Objs; |
4480 | getUnderlyingObjects(V, Objs); |
4481 | |
4482 | for (const Value *V : Objs) { |
4483 | if (!Visited.insert(V).second) |
4484 | continue; |
4485 | if (Operator::getOpcode(V) == Instruction::IntToPtr) { |
4486 | const Value *O = |
4487 | getUnderlyingObjectFromInt(cast<User>(V)->getOperand(0)); |
4488 | if (O->getType()->isPointerTy()) { |
4489 | Working.push_back(O); |
4490 | continue; |
4491 | } |
4492 | } |
4493 | |
4494 | |
4495 | if (!isIdentifiedObject(V)) { |
4496 | Objects.clear(); |
4497 | return false; |
4498 | } |
4499 | Objects.push_back(const_cast<Value *>(V)); |
4500 | } |
4501 | } while (!Working.empty()); |
4502 | return true; |
4503 | } |
4504 | |
4505 | AllocaInst *llvm::findAllocaForValue(Value *V, bool OffsetZero) { |
4506 | AllocaInst *Result = nullptr; |
4507 | SmallPtrSet<Value *, 4> Visited; |
4508 | SmallVector<Value *, 4> Worklist; |
4509 | |
4510 | auto AddWork = [&](Value *V) { |
4511 | if (Visited.insert(V).second) |
4512 | Worklist.push_back(V); |
4513 | }; |
4514 | |
4515 | AddWork(V); |
4516 | do { |
4517 | V = Worklist.pop_back_val(); |
4518 | assert(Visited.count(V)); |
4519 | |
4520 | if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) { |
4521 | if (Result && Result != AI) |
4522 | return nullptr; |
4523 | Result = AI; |
4524 | } else if (CastInst *CI = dyn_cast<CastInst>(V)) { |
4525 | AddWork(CI->getOperand(0)); |
4526 | } else if (PHINode *PN = dyn_cast<PHINode>(V)) { |
4527 | for (Value *IncValue : PN->incoming_values()) |
4528 | AddWork(IncValue); |
4529 | } else if (auto *SI = dyn_cast<SelectInst>(V)) { |
4530 | AddWork(SI->getTrueValue()); |
4531 | AddWork(SI->getFalseValue()); |
4532 | } else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(V)) { |
4533 | if (OffsetZero && !GEP->hasAllZeroIndices()) |
4534 | return nullptr; |
4535 | AddWork(GEP->getPointerOperand()); |
4536 | } else { |
4537 | return nullptr; |
4538 | } |
4539 | } while (!Worklist.empty()); |
4540 | |
4541 | return Result; |
4542 | } |
4543 | |
4544 | static bool onlyUsedByLifetimeMarkersOrDroppableInstsHelper( |
4545 | const Value *V, bool AllowLifetime, bool AllowDroppable) { |
4546 | for (const User *U : V->users()) { |
4547 | const IntrinsicInst *II = dyn_cast<IntrinsicInst>(U); |
4548 | if (!II) |
4549 | return false; |
4550 | |
4551 | if (AllowLifetime && II->isLifetimeStartOrEnd()) |
4552 | continue; |
4553 | |
4554 | if (AllowDroppable && II->isDroppable()) |
4555 | continue; |
4556 | |
4557 | return false; |
4558 | } |
4559 | return true; |
4560 | } |
4561 | |
4562 | bool llvm::onlyUsedByLifetimeMarkers(const Value *V) { |
4563 | return onlyUsedByLifetimeMarkersOrDroppableInstsHelper( |
4564 | V, true, false); |
4565 | } |
4566 | bool llvm::onlyUsedByLifetimeMarkersOrDroppableInsts(const Value *V) { |
4567 | return onlyUsedByLifetimeMarkersOrDroppableInstsHelper( |
4568 | V, true, true); |
4569 | } |
4570 | |
4571 | bool llvm::mustSuppressSpeculation(const LoadInst &LI) { |
4572 | if (!LI.isUnordered()) |
4573 | return true; |
4574 | const Function &F = *LI.getFunction(); |
4575 | |
4576 | return F.hasFnAttribute(Attribute::SanitizeThread) || |
4577 | |
4578 | F.hasFnAttribute(Attribute::SanitizeAddress) || |
4579 | F.hasFnAttribute(Attribute::SanitizeHWAddress); |
4580 | } |
4581 | |
4582 | |
4583 | bool llvm::isSafeToSpeculativelyExecute(const Value *V, |
4584 | const Instruction *CtxI, |
4585 | const DominatorTree *DT, |
4586 | const TargetLibraryInfo *TLI) { |
4587 | const Operator *Inst = dyn_cast<Operator>(V); |
4588 | if (!Inst) |
4589 | return false; |
4590 | |
4591 | for (unsigned i = 0, e = Inst->getNumOperands(); i != e; ++i) |
4592 | if (Constant *C = dyn_cast<Constant>(Inst->getOperand(i))) |
4593 | if (C->canTrap()) |
4594 | return false; |
4595 | |
4596 | switch (Inst->getOpcode()) { |
4597 | default: |
4598 | return true; |
4599 | case Instruction::UDiv: |
4600 | case Instruction::URem: { |
4601 | |
4602 | const APInt *V; |
4603 | if (match(Inst->getOperand(1), m_APInt(V))) |
4604 | return *V != 0; |
4605 | return false; |
4606 | } |
4607 | case Instruction::SDiv: |
4608 | case Instruction::SRem: { |
4609 | |
4610 | const APInt *Numerator, *Denominator; |
4611 | if (!match(Inst->getOperand(1), m_APInt(Denominator))) |
4612 | return false; |
4613 | |
4614 | if (*Denominator == 0) |
4615 | return false; |
4616 | |
4617 | if (!Denominator->isAllOnesValue()) |
4618 | return true; |
4619 | |
4620 | |
4621 | if (match(Inst->getOperand(0), m_APInt(Numerator))) |
4622 | return !Numerator->isMinSignedValue(); |
4623 | |
4624 | return false; |
4625 | } |
4626 | case Instruction::Load: { |
4627 | const LoadInst *LI = cast<LoadInst>(Inst); |
4628 | if (mustSuppressSpeculation(*LI)) |
4629 | return false; |
4630 | const DataLayout &DL = LI->getModule()->getDataLayout(); |
4631 | return isDereferenceableAndAlignedPointer( |
4632 | LI->getPointerOperand(), LI->getType(), MaybeAlign(LI->getAlignment()), |
4633 | DL, CtxI, DT, TLI); |
4634 | } |
4635 | case Instruction::Call: { |
4636 | auto *CI = cast<const CallInst>(Inst); |
4637 | const Function *Callee = CI->getCalledFunction(); |
4638 | |
4639 | |
4640 | |
4641 | return Callee && Callee->isSpeculatable(); |
4642 | } |
4643 | case Instruction::VAArg: |
4644 | case Instruction::Alloca: |
4645 | case Instruction::Invoke: |
4646 | case Instruction::CallBr: |
4647 | case Instruction::PHI: |
4648 | case Instruction::Store: |
4649 | case Instruction::Ret: |
4650 | case Instruction::Br: |
4651 | case Instruction::IndirectBr: |
4652 | case Instruction::Switch: |
4653 | case Instruction::Unreachable: |
4654 | case Instruction::Fence: |
4655 | case Instruction::AtomicRMW: |
4656 | case Instruction::AtomicCmpXchg: |
4657 | case Instruction::LandingPad: |
4658 | case Instruction::Resume: |
4659 | case Instruction::CatchSwitch: |
4660 | case Instruction::CatchPad: |
4661 | case Instruction::CatchRet: |
4662 | case Instruction::CleanupPad: |
4663 | case Instruction::CleanupRet: |
4664 | return false; |
4665 | } |
4666 | } |
4667 | |
4668 | bool llvm::mayBeMemoryDependent(const Instruction &I) { |
4669 | return I.mayReadOrWriteMemory() || !isSafeToSpeculativelyExecute(&I); |
4670 | } |
4671 | |
4672 | |
4673 | static OverflowResult mapOverflowResult(ConstantRange::OverflowResult OR) { |
4674 | switch (OR) { |
4675 | case ConstantRange::OverflowResult::MayOverflow: |
4676 | return OverflowResult::MayOverflow; |
4677 | case ConstantRange::OverflowResult::AlwaysOverflowsLow: |
4678 | return OverflowResult::AlwaysOverflowsLow; |
4679 | case ConstantRange::OverflowResult::AlwaysOverflowsHigh: |
4680 | return OverflowResult::AlwaysOverflowsHigh; |
4681 | case ConstantRange::OverflowResult::NeverOverflows: |
4682 | return OverflowResult::NeverOverflows; |
4683 | } |
4684 | llvm_unreachable("Unknown OverflowResult"); |
4685 | } |
4686 | |
4687 | |
4688 | static ConstantRange computeConstantRangeIncludingKnownBits( |
4689 | const Value *V, bool ForSigned, const DataLayout &DL, unsigned Depth, |
4690 | AssumptionCache *AC, const Instruction *CxtI, const DominatorTree *DT, |
4691 | OptimizationRemarkEmitter *ORE = nullptr, bool UseInstrInfo = true) { |
4692 | KnownBits Known = computeKnownBits( |
4693 | V, DL, Depth, AC, CxtI, DT, ORE, UseInstrInfo); |
4694 | ConstantRange CR1 = ConstantRange::fromKnownBits(Known, ForSigned); |
4695 | ConstantRange CR2 = computeConstantRange(V, UseInstrInfo); |
4696 | ConstantRange::PreferredRangeType RangeType = |
4697 | ForSigned ? ConstantRange::Signed : ConstantRange::Unsigned; |
4698 | return CR1.intersectWith(CR2, RangeType); |
4699 | } |
4700 | |
4701 | OverflowResult llvm::computeOverflowForUnsignedMul( |
4702 | const Value *LHS, const Value *RHS, const DataLayout &DL, |
4703 | AssumptionCache *AC, const Instruction *CxtI, const DominatorTree *DT, |
4704 | bool UseInstrInfo) { |
4705 | KnownBits LHSKnown = computeKnownBits(LHS, DL, 0, AC, CxtI, DT, |
4706 | nullptr, UseInstrInfo); |
4707 | KnownBits RHSKnown = computeKnownBits(RHS, DL, 0, AC, CxtI, DT, |
4708 | nullptr, UseInstrInfo); |
4709 | ConstantRange LHSRange = ConstantRange::fromKnownBits(LHSKnown, false); |
4710 | ConstantRange RHSRange = ConstantRange::fromKnownBits(RHSKnown, false); |
4711 | return mapOverflowResult(LHSRange.unsignedMulMayOverflow(RHSRange)); |
4712 | } |
4713 | |
4714 | OverflowResult |
4715 | llvm::computeOverflowForSignedMul(const Value *LHS, const Value *RHS, |
4716 | const DataLayout &DL, AssumptionCache *AC, |
4717 | const Instruction *CxtI, |
4718 | const DominatorTree *DT, bool UseInstrInfo) { |
4719 | |
4720 | |
4721 | |
4722 | |
4723 | |
4724 | |
4725 | unsigned BitWidth = LHS->getType()->getScalarSizeInBits(); |
4726 | |
4727 | |
4728 | |
4729 | unsigned SignBits = ComputeNumSignBits(LHS, DL, 0, AC, CxtI, DT) + |
4730 | ComputeNumSignBits(RHS, DL, 0, AC, CxtI, DT); |
4731 | |
4732 | |
4733 | |
4734 | if (SignBits > BitWidth + 1) |
4735 | return OverflowResult::NeverOverflows; |
4736 | |
4737 | |
4738 | |
4739 | |
4740 | |
4741 | |
4742 | if (SignBits == BitWidth + 1) { |
4743 | |
4744 | |
4745 | |
4746 | |
4747 | KnownBits LHSKnown = computeKnownBits(LHS, DL, 0, AC, CxtI, DT, |
4748 | nullptr, UseInstrInfo); |
4749 | KnownBits RHSKnown = computeKnownBits(RHS, DL, 0, AC, CxtI, DT, |
4750 | nullptr, UseInstrInfo); |
4751 | if (LHSKnown.isNonNegative() || RHSKnown.isNonNegative()) |
4752 | return OverflowResult::NeverOverflows; |
4753 | } |
4754 | return OverflowResult::MayOverflow; |
4755 | } |
4756 | |
4757 | OverflowResult llvm::computeOverflowForUnsignedAdd( |
4758 | const Value *LHS, const Value *RHS, const DataLayout &DL, |
4759 | AssumptionCache *AC, const Instruction *CxtI, const DominatorTree *DT, |
4760 | bool UseInstrInfo) { |
4761 | ConstantRange LHSRange = computeConstantRangeIncludingKnownBits( |
4762 | LHS, false, DL, 0, AC, CxtI, DT, |
4763 | nullptr, UseInstrInfo); |
4764 | ConstantRange RHSRange = computeConstantRangeIncludingKnownBits( |
4765 | RHS, false, DL, 0, AC, CxtI, DT, |
4766 | nullptr, UseInstrInfo); |
4767 | return mapOverflowResult(LHSRange.unsignedAddMayOverflow(RHSRange)); |
4768 | } |
4769 | |
4770 | static OverflowResult computeOverflowForSignedAdd(const Value *LHS, |
4771 | const Value *RHS, |
4772 | const AddOperator *Add, |
4773 | const DataLayout &DL, |
4774 | AssumptionCache *AC, |
4775 | const Instruction *CxtI, |
4776 | const DominatorTree *DT) { |
4777 | if (Add && Add->hasNoSignedWrap()) { |
4778 | return OverflowResult::NeverOverflows; |
4779 | } |
4780 | |
4781 | |
4782 | |
4783 | |
4784 | |
4785 | |
4786 | |
4787 | |
4788 | |
4789 | |
4790 | |
4791 | |
4792 | |
4793 | |
4794 | |
4795 | if (ComputeNumSignBits(LHS, DL, 0, AC, CxtI, DT) > 1 && |
4796 | ComputeNumSignBits(RHS, DL, 0, AC, CxtI, DT) > 1) |
4797 | return OverflowResult::NeverOverflows; |
4798 | |
4799 | ConstantRange LHSRange = computeConstantRangeIncludingKnownBits( |
4800 | LHS, true, DL, 0, AC, CxtI, DT); |
4801 | ConstantRange RHSRange = computeConstantRangeIncludingKnownBits( |
4802 | RHS, true, DL, 0, AC, CxtI, DT); |
4803 | OverflowResult OR = |
4804 | mapOverflowResult(LHSRange.signedAddMayOverflow(RHSRange)); |
4805 | if (OR != OverflowResult::MayOverflow) |
4806 | return OR; |
4807 | |
4808 | |
4809 | if (!Add) |
4810 | return OverflowResult::MayOverflow; |
4811 | |
4812 | |
4813 | |
4814 | |
4815 | |
4816 | |
4817 | bool LHSOrRHSKnownNonNegative = |
4818 | (LHSRange.isAllNonNegative() || RHSRange.isAllNonNegative()); |
4819 | bool LHSOrRHSKnownNegative = |
4820 | (LHSRange.isAllNegative() || RHSRange.isAllNegative()); |
4821 | if (LHSOrRHSKnownNonNegative || LHSOrRHSKnownNegative) { |
4822 | KnownBits AddKnown(LHSRange.getBitWidth()); |
4823 | computeKnownBitsFromAssume( |
4824 | Add, AddKnown, 0, Query(DL, AC, CxtI, DT, true)); |
4825 | if ((AddKnown.isNonNegative() && LHSOrRHSKnownNonNegative) || |
4826 | (AddKnown.isNegative() && LHSOrRHSKnownNegative)) |
4827 | return OverflowResult::NeverOverflows; |
4828 | } |
4829 | |
4830 | return OverflowResult::MayOverflow; |
4831 | } |
4832 | |
4833 | OverflowResult llvm::computeOverflowForUnsignedSub(const Value *LHS, |
4834 | const Value *RHS, |
4835 | const DataLayout &DL, |
4836 | AssumptionCache *AC, |
4837 | const Instruction *CxtI, |
4838 | const DominatorTree *DT) { |
4839 | |
4840 | |
4841 | if (match(CxtI, |
4842 | m_Intrinsic<Intrinsic::usub_with_overflow>(m_Value(), m_Value()))) |
4843 | if (auto C = |
4844 | isImpliedByDomCondition(CmpInst::ICMP_UGE, LHS, RHS, CxtI, DL)) { |
4845 | if (*C) |
4846 | return OverflowResult::NeverOverflows; |
4847 | return OverflowResult::AlwaysOverflowsLow; |
4848 | } |
4849 | ConstantRange LHSRange = computeConstantRangeIncludingKnownBits( |
4850 | LHS, false, DL, 0, AC, CxtI, DT); |
4851 | ConstantRange RHSRange = computeConstantRangeIncludingKnownBits( |
4852 | RHS, false, DL, 0, AC, CxtI, DT); |
4853 | return mapOverflowResult(LHSRange.unsignedSubMayOverflow(RHSRange)); |
4854 | } |
4855 | |
4856 | OverflowResult llvm::computeOverflowForSignedSub(const Value *LHS, |
4857 | const Value *RHS, |
4858 | const DataLayout &DL, |
4859 | AssumptionCache *AC, |
4860 | const Instruction *CxtI, |
4861 | const DominatorTree *DT) { |
4862 | |
4863 | |
4864 | if (ComputeNumSignBits(LHS, DL, 0, AC, CxtI, DT) > 1 && |
4865 | ComputeNumSignBits(RHS, DL, 0, AC, CxtI, DT) > 1) |
4866 | return OverflowResult::NeverOverflows; |
4867 | |
4868 | ConstantRange LHSRange = computeConstantRangeIncludingKnownBits( |
4869 | LHS, true, DL, 0, AC, CxtI, DT); |
4870 | ConstantRange RHSRange = computeConstantRangeIncludingKnownBits( |
4871 | RHS, true, DL, 0, AC, CxtI, DT); |
4872 | return mapOverflowResult(LHSRange.signedSubMayOverflow(RHSRange)); |
4873 | } |
4874 | |
4875 | bool llvm::isOverflowIntrinsicNoWrap(const WithOverflowInst *WO, |
4876 | const DominatorTree &DT) { |
4877 | SmallVector<const BranchInst *, 2> GuardingBranches; |
4878 | SmallVector<const ExtractValueInst *, 2> Results; |
4879 | |
4880 | for (const User *U : WO->users()) { |
4881 | if (const auto *EVI = dyn_cast<ExtractValueInst>(U)) { |
4882 | assert(EVI->getNumIndices() == 1 && "Obvious from CI's type"); |
4883 | |
4884 | if (EVI->getIndices()[0] == 0) |
4885 | Results.push_back(EVI); |
4886 | else { |
4887 | assert(EVI->getIndices()[0] == 1 && "Obvious from CI's type"); |
4888 | |
4889 | for (const auto *U : EVI->users()) |
4890 | if (const auto *B = dyn_cast<BranchInst>(U)) { |
4891 | assert(B->isConditional() && "How else is it using an i1?"); |
4892 | GuardingBranches.push_back(B); |
4893 | } |
4894 | } |
4895 | } else { |
4896 | |
4897 | |
4898 | return false; |
4899 | } |
4900 | } |
4901 | |
4902 | auto AllUsesGuardedByBranch = [&](const BranchInst *BI) { |
4903 | BasicBlockEdge NoWrapEdge(BI->getParent(), BI->getSuccessor(1)); |
4904 | if (!NoWrapEdge.isSingleEdge()) |
4905 | return false; |
4906 | |
4907 | |
4908 | for (const auto *Result : Results) { |
4909 | |
4910 | |
4911 | if (DT.dominates(NoWrapEdge, Result->getParent())) |
4912 | continue; |
4913 | |
4914 | for (auto &RU : Result->uses()) |
4915 | if (!DT.dominates(NoWrapEdge, RU)) |
4916 | return false; |
4917 | } |
4918 | |
4919 | return true; |
4920 | }; |
4921 | |
4922 | return llvm::any_of(GuardingBranches, AllUsesGuardedByBranch); |
4923 | } |
4924 | |
4925 | static bool canCreateUndefOrPoison(const Operator *Op, bool PoisonOnly) { |
4926 | |
4927 | if (const auto *OvOp = dyn_cast<OverflowingBinaryOperator>(Op)) { |
4928 | if (OvOp->hasNoSignedWrap() || OvOp->hasNoUnsignedWrap()) |
4929 | return true; |
4930 | } |
4931 | if (const auto *ExactOp = dyn_cast<PossiblyExactOperator>(Op)) |
4932 | if (ExactOp->isExact()) |
4933 | return true; |
4934 | if (const auto *FP = dyn_cast<FPMathOperator>(Op)) { |
4935 | auto FMF = FP->getFastMathFlags(); |
4936 | if (FMF.noNaNs() || FMF.noInfs()) |
4937 | return true; |
4938 | } |
4939 | |
4940 | unsigned Opcode = Op->getOpcode(); |
4941 | |
4942 | |
4943 | switch (Opcode) { |
4944 | case Instruction::Shl: |
4945 | case Instruction::AShr: |
4946 | case Instruction::LShr: { |
4947 | |
4948 | if (auto *C = dyn_cast<Constant>(Op->getOperand(1))) { |
4949 | SmallVector<Constant *, 4> ShiftAmounts; |
4950 | if (auto *FVTy = dyn_cast<FixedVectorType>(C->getType())) { |
4951 | unsigned NumElts = FVTy->getNumElements(); |
4952 | for (unsigned i = 0; i < NumElts; ++i) |
4953 | ShiftAmounts.push_back(C->getAggregateElement(i)); |
4954 | } else if (isa<ScalableVectorType>(C->getType())) |
4955 | return true; |
4956 | else |
4957 | ShiftAmounts.push_back(C); |
4958 | |
4959 | bool Safe = llvm::all_of(ShiftAmounts, [](Constant *C) { |
4960 | auto *CI = dyn_cast_or_null<ConstantInt>(C); |
4961 | return CI && CI->getValue().ult(C->getType()->getIntegerBitWidth()); |
4962 | }); |
4963 | return !Safe; |
4964 | } |
4965 | return true; |
4966 | } |
4967 | case Instruction::FPToSI: |
4968 | case Instruction::FPToUI: |
4969 | |
4970 | |
4971 | return true; |
4972 | case Instruction::Call: |
4973 | if (auto *II = dyn_cast<IntrinsicInst>(Op)) { |
4974 | switch (II->getIntrinsicID()) { |
4975 | |
4976 | case Intrinsic::ctpop: |
4977 | case Intrinsic::sadd_with_overflow: |
4978 | case Intrinsic::ssub_with_overflow: |
4979 | case Intrinsic::smul_with_overflow: |
4980 | case Intrinsic::uadd_with_overflow: |
4981 | case Intrinsic::usub_with_overflow: |
4982 | case Intrinsic::umul_with_overflow: |
4983 | return false; |
4984 | } |
4985 | } |
4986 | LLVM_FALLTHROUGH; |
4987 | case Instruction::CallBr: |
4988 | case Instruction::Invoke: { |
4989 | const auto *CB = cast<CallBase>(Op); |
4990 | return !CB->hasRetAttr(Attribute::NoUndef); |
4991 | } |
4992 | case Instruction::InsertElement: |
4993 | case Instruction::ExtractElement: { |
4994 | |
4995 | auto *VTy = cast<VectorType>(Op->getOperand(0)->getType()); |
4996 | unsigned IdxOp = Op->getOpcode() == Instruction::InsertElement ? 2 : 1; |
4997 | auto *Idx = dyn_cast<ConstantInt>(Op->getOperand(IdxOp)); |
4998 | if (!Idx || Idx->getValue().uge(VTy->getElementCount().getKnownMinValue())) |
4999 | return true; |
5000 | return false; |
5001 | } |
5002 | case Instruction::ShuffleVector: { |
5003 | |
5004 | if (PoisonOnly) |
5005 | return false; |
5006 | ArrayRef<int> Mask = isa<ConstantExpr>(Op) |
5007 | ? cast<ConstantExpr>(Op)->getShuffleMask() |
5008 | : cast<ShuffleVectorInst>(Op)->getShuffleMask(); |
5009 | return is_contained(Mask, UndefMaskElem); |
5010 | } |
5011 | case Instruction::FNeg: |
5012 | case Instruction::PHI: |
5013 | case Instruction::Select: |
5014 | case Instruction::URem: |
5015 | case Instruction::SRem: |
5016 | case Instruction::ExtractValue: |
5017 | case Instruction::InsertValue: |
5018 | case Instruction::Freeze: |
5019 | case Instruction::ICmp: |
5020 | case Instruction::FCmp: |
5021 | return false; |
5022 | case Instruction::GetElementPtr: { |
5023 | const auto *GEP = cast<GEPOperator>(Op); |
5024 | return GEP->isInBounds(); |
5025 | } |
5026 | default: { |
5027 | const auto *CE = dyn_cast<ConstantExpr>(Op); |
5028 | if (isa<CastInst>(Op) || (CE && CE->isCast())) |
5029 | return false; |
5030 | else if (Instruction::isBinaryOp(Opcode)) |
5031 | return false; |
5032 | |
5033 | return true; |
5034 | } |
5035 | } |
5036 | } |
5037 | |
5038 | bool llvm::canCreateUndefOrPoison(const Operator *Op) { |
5039 | return ::canCreateUndefOrPoison(Op, false); |
5040 | } |
5041 | |
5042 | bool llvm::canCreatePoison(const Operator *Op) { |
5043 | return ::canCreateUndefOrPoison(Op, true); |
5044 | } |
5045 | |
5046 | static bool directlyImpliesPoison(const Value *ValAssumedPoison, |
5047 | const Value *V, unsigned Depth) { |
5048 | if (ValAssumedPoison == V) |
5049 | return true; |
5050 | |
5051 | const unsigned MaxDepth = 2; |
5052 | if (Depth >= MaxDepth) |
5053 | return false; |
5054 | |
5055 | if (const auto *I = dyn_cast<Instruction>(V)) { |
5056 | if (propagatesPoison(cast<Operator>(I))) |
5057 | return any_of(I->operands(), [=](const Value *Op) { |
5058 | return directlyImpliesPoison(ValAssumedPoison, Op, Depth + 1); |
5059 | }); |
5060 | |
5061 | |
5062 | if (const auto *SI = dyn_cast<SelectInst>(I)) |
5063 | return directlyImpliesPoison(ValAssumedPoison, SI->getCondition(), |
5064 | Depth + 1); |
5065 | |
5066 | |
5067 | |
5068 | const WithOverflowInst *II; |
5069 | if (match(I, m_ExtractValue(m_WithOverflowInst(II))) && |
5070 | (match(ValAssumedPoison, m_ExtractValue(m_Specific(II))) || |
5071 | llvm::is_contained(II->arg_operands(), ValAssumedPoison))) |
5072 | return true; |
5073 | } |
5074 | return false; |
5075 | } |
5076 | |
5077 | static bool impliesPoison(const Value *ValAssumedPoison, const Value *V, |
5078 | unsigned Depth) { |
5079 | if (isGuaranteedNotToBeUndefOrPoison(ValAssumedPoison)) |
5080 | return true; |
5081 | |
5082 | if (directlyImpliesPoison(ValAssumedPoison, V, 0)) |
5083 | return true; |
5084 | |
5085 | const unsigned MaxDepth = 2; |
5086 | if (Depth >= MaxDepth) |
5087 | return false; |
5088 | |
5089 | const auto *I = dyn_cast<Instruction>(ValAssumedPoison); |
5090 | if (I && !canCreatePoison(cast<Operator>(I))) { |
5091 | return all_of(I->operands(), [=](const Value *Op) { |
5092 | return impliesPoison(Op, V, Depth + 1); |
5093 | }); |
5094 | } |
5095 | return false; |
5096 | } |
5097 | |
5098 | bool llvm::impliesPoison(const Value *ValAssumedPoison, const Value *V) { |
5099 | return ::impliesPoison(ValAssumedPoison, V, 0); |
5100 | } |
5101 | |
5102 | static bool programUndefinedIfUndefOrPoison(const Value *V, |
5103 | bool PoisonOnly); |
5104 | |
5105 | static bool isGuaranteedNotToBeUndefOrPoison(const Value *V, |
5106 | AssumptionCache *AC, |
5107 | const Instruction *CtxI, |
5108 | const DominatorTree *DT, |
5109 | unsigned Depth, bool PoisonOnly) { |
5110 | if (Depth >= MaxAnalysisRecursionDepth) |
5111 | return false; |
5112 | |
5113 | if (isa<MetadataAsValue>(V)) |
5114 | return false; |
5115 | |
5116 | if (const auto *A = dyn_cast<Argument>(V)) { |
5117 | if (A->hasAttribute(Attribute::NoUndef)) |
5118 | return true; |
5119 | } |
5120 | |
5121 | if (auto *C = dyn_cast<Constant>(V)) { |
5122 | if (isa<UndefValue>(C)) |
5123 | return PoisonOnly && !isa<PoisonValue>(C); |
5124 | |
5125 | if (isa<ConstantInt>(C) || isa<GlobalVariable>(C) || isa<ConstantFP>(V) || |
5126 | isa<ConstantPointerNull>(C) || isa<Function>(C)) |
5127 | return true; |
5128 | |
5129 | if (C->getType()->isVectorTy() && !isa<ConstantExpr>(C)) |
5130 | return (PoisonOnly ? !C->containsPoisonElement() |
5131 | : !C->containsUndefOrPoisonElement()) && |
5132 | !C->containsConstantExpression(); |
5133 | } |
5134 | |
5135 | |
5136 | |
5137 | |
5138 | |
5139 | |
5140 | |
5141 | |
5142 | |
5143 | auto *StrippedV = V->stripPointerCastsSameRepresentation(); |
5144 | if (isa<AllocaInst>(StrippedV) || isa<GlobalVariable>(StrippedV) || |
5145 | isa<Function>(StrippedV) || isa<ConstantPointerNull>(StrippedV)) |
5146 | return true; |
5147 | |
5148 | auto OpCheck = [&](const Value *V) { |
5149 | return isGuaranteedNotToBeUndefOrPoison(V, AC, CtxI, DT, Depth + 1, |
5150 | PoisonOnly); |
5151 | }; |
5152 | |
5153 | if (auto *Opr = dyn_cast<Operator>(V)) { |
5154 | |
5155 | |
5156 | if (isa<FreezeInst>(V)) |
5157 | return true; |
5158 | |
5159 | if (const auto *CB = dyn_cast<CallBase>(V)) { |
5160 | if (CB->hasRetAttr(Attribute::NoUndef)) |
5161 | return true; |
5162 | } |
5163 | |
5164 | if (const auto *PN = dyn_cast<PHINode>(V)) { |
5165 | unsigned Num = PN->getNumIncomingValues(); |
5166 | bool IsWellDefined = true; |
5167 | for (unsigned i = 0; i < Num; ++i) { |
5168 | auto *TI = PN->getIncomingBlock(i)->getTerminator(); |
5169 | if (!isGuaranteedNotToBeUndefOrPoison(PN->getIncomingValue(i), AC, TI, |
5170 | DT, Depth + 1, PoisonOnly)) { |
5171 | IsWellDefined = false; |
5172 | break; |
5173 | } |
5174 | } |
5175 | if (IsWellDefined) |
5176 | return true; |
5177 | } else if (!canCreateUndefOrPoison(Opr) && all_of(Opr->operands(), OpCheck)) |
5178 | return true; |
5179 | } |
5180 | |
5181 | if (auto *I = dyn_cast<LoadInst>(V)) |
5182 | if (I->getMetadata(LLVMContext::MD_noundef)) |
5183 | return true; |
5184 | |
5185 | if (programUndefinedIfUndefOrPoison(V, PoisonOnly)) |
5186 | return true; |
5187 | |
5188 | |
5189 | if (!CtxI || !CtxI->getParent() || !DT) |
5190 | return false; |
5191 | |
5192 | auto *DNode = DT->getNode(CtxI->getParent()); |
5193 | if (!DNode) |
5194 | |
5195 | return false; |
5196 | |
5197 | |
5198 | |
5199 | |
5200 | |
5201 | |
5202 | auto *Dominator = DNode->getIDom(); |
5203 | while (Dominator) { |
5204 | auto *TI = Dominator->getBlock()->getTerminator(); |
5205 | |
5206 | Value *Cond = nullptr; |
5207 | if (auto BI = dyn_cast<BranchInst>(TI)) { |
5208 | if (BI->isConditional()) |
5209 | Cond = BI->getCondition(); |
5210 | } else if (auto SI = dyn_cast<SwitchInst>(TI)) { |
5211 | Cond = SI->getCondition(); |
5212 | } |
5213 | |
5214 | if (Cond) { |
5215 | if (Cond == V) |
5216 | return true; |
5217 | else if (PoisonOnly && isa<Operator>(Cond)) { |
5218 | |
5219 | auto *Opr = cast<Operator>(Cond); |
5220 | if (propagatesPoison(Opr) && is_contained(Opr->operand_values(), V)) |
5221 | return true; |
5222 | } |
5223 | } |
5224 | |
5225 | Dominator = Dominator->getIDom(); |
5226 | } |
5227 | |
5228 | SmallVector<Attribute::AttrKind, 2> AttrKinds{Attribute::NoUndef}; |
5229 | if (getKnowledgeValidInContext(V, AttrKinds, CtxI, DT, AC)) |
5230 | return true; |
5231 | |
5232 | return false; |
5233 | } |
5234 | |
5235 | bool llvm::isGuaranteedNotToBeUndefOrPoison(const Value *V, AssumptionCache *AC, |
5236 | const Instruction *CtxI, |
5237 | const DominatorTree *DT, |
5238 | unsigned Depth) { |
5239 | return ::isGuaranteedNotToBeUndefOrPoison(V, AC, CtxI, DT, Depth, false); |
5240 | } |
5241 | |
5242 | bool llvm::isGuaranteedNotToBePoison(const Value *V, AssumptionCache *AC, |
5243 | const Instruction *CtxI, |
5244 | const DominatorTree *DT, unsigned Depth) { |
5245 | return ::isGuaranteedNotToBeUndefOrPoison(V, AC, CtxI, DT, Depth, true); |
5246 | } |
5247 | |
5248 | OverflowResult llvm::computeOverflowForSignedAdd(const AddOperator *Add, |
5249 | const DataLayout &DL, |
5250 | AssumptionCache *AC, |
5251 | const Instruction *CxtI, |
5252 | const DominatorTree *DT) { |
5253 | return ::computeOverflowForSignedAdd(Add->getOperand(0), Add->getOperand(1), |
5254 | Add, DL, AC, CxtI, DT); |
5255 | } |
5256 | |
5257 | OverflowResult llvm::computeOverflowForSignedAdd(const Value *LHS, |
5258 | const Value *RHS, |
5259 | const DataLayout &DL, |
5260 | AssumptionCache *AC, |
5261 | const Instruction *CxtI, |
5262 | const DominatorTree *DT) { |
5263 | return ::computeOverflowForSignedAdd(LHS, RHS, nullptr, DL, AC, CxtI, DT); |
5264 | } |
5265 | |
5266 | bool llvm::isGuaranteedToTransferExecutionToSuccessor(const Instruction *I) { |
5267 | |
5268 | |
5269 | |
5270 | |
5271 | |
5272 | if (isa<ReturnInst>(I)) |
5273 | return false; |
5274 | if (isa<UnreachableInst>(I)) |
5275 | return false; |
5276 | |
5277 | |
5278 | |
5279 | |
5280 | |
5281 | if (isa<CatchPadInst>(I)) { |
5282 | switch (classifyEHPersonality(I->getFunction()->getPersonalityFn())) { |
5283 | default: |
5284 | |
5285 | |
5286 | return false; |
5287 | case EHPersonality::CoreCLR: |
5288 | |
5289 | return true; |
5290 | } |
5291 | } |
5292 | |
5293 | |
5294 | |
5295 | return !I->mayThrow() && I->willReturn(); |
5296 | } |
5297 | |
5298 | bool llvm::isGuaranteedToTransferExecutionToSuccessor(const BasicBlock *BB) { |
5299 | |
5300 | |
5301 | for (const Instruction &I : *BB) |
5302 | if (!isGuaranteedToTransferExecutionToSuccessor(&I)) |
5303 | return false; |
5304 | return true; |
5305 | } |
5306 | |
5307 | bool llvm::isGuaranteedToExecuteForEveryIteration(const Instruction *I, |
5308 | const Loop *L) { |
5309 | |
5310 | |
5311 | |
5312 | |
5313 | if (I->getParent() != L->getHeader()) return false; |
5314 | |
5315 | for (const Instruction &LI : *L->getHeader()) { |
5316 | if (&LI == I) return true; |
5317 | if (!isGuaranteedToTransferExecutionToSuccessor(&LI)) return false; |
5318 | } |
5319 | llvm_unreachable("Instruction not contained in its own parent basic block."); |
5320 | } |
5321 | |
5322 | bool llvm::propagatesPoison(const Operator *I) { |
5323 | switch (I->getOpcode()) { |
5324 | case Instruction::Freeze: |
5325 | case Instruction::Select: |
5326 | case Instruction::PHI: |
5327 | case Instruction::Invoke: |
5328 | return false; |
5329 | case Instruction::Call: |
5330 | if (auto *II = dyn_cast<IntrinsicInst>(I)) { |
5331 | switch (II->getIntrinsicID()) { |
5332 | |
5333 | case Intrinsic::sadd_with_overflow: |
5334 | case Intrinsic::ssub_with_overflow: |
5335 | case Intrinsic::smul_with_overflow: |
5336 | case Intrinsic::uadd_with_overflow: |
5337 | case Intrinsic::usub_with_overflow: |
5338 | case Intrinsic::umul_with_overflow: |
5339 | |
5340 | |
5341 | |
5342 | return true; |
5343 | case Intrinsic::ctpop: |
5344 | return true; |
5345 | } |
5346 | } |
5347 | return false; |
5348 | case Instruction::ICmp: |
5349 | case Instruction::FCmp: |
5350 | case Instruction::GetElementPtr: |
5351 | return true; |
5352 | default: |
5353 | if (isa<BinaryOperator>(I) || isa<UnaryOperator>(I) || isa<CastInst>(I)) |
5354 | return true; |
5355 | |
5356 | |
5357 | return false; |
5358 | } |
5359 | } |
5360 | |
5361 | void llvm::getGuaranteedWellDefinedOps( |
5362 | const Instruction *I, SmallPtrSetImpl<const Value *> &Operands) { |
5363 | switch (I->getOpcode()) { |
5364 | case Instruction::Store: |
5365 | Operands.insert(cast<StoreInst>(I)->getPointerOperand()); |
5366 | break; |
5367 | |
5368 | case Instruction::Load: |
5369 | Operands.insert(cast<LoadInst>(I)->getPointerOperand()); |
5370 | break; |
5371 | |
5372 | |
5373 | |
5374 | case Instruction::AtomicCmpXchg: |
5375 | Operands.insert(cast<AtomicCmpXchgInst>(I)->getPointerOperand()); |
5376 | break; |
5377 | |
5378 | case Instruction::AtomicRMW: |
5379 | Operands.insert(cast<AtomicRMWInst>(I)->getPointerOperand()); |
5380 | break; |
5381 | |
5382 | case Instruction::Call: |
5383 | case Instruction::Invoke: { |
5384 | const CallBase *CB = cast<CallBase>(I); |
5385 | if (CB->isIndirectCall()) |
5386 | Operands.insert(CB->getCalledOperand()); |
5387 | for (unsigned i = 0; i < CB->arg_size(); ++i) { |
5388 | if (CB->paramHasAttr(i, Attribute::NoUndef) || |
5389 | CB->paramHasAttr(i, Attribute::Dereferenceable)) |
5390 | Operands.insert(CB->getArgOperand(i)); |
5391 | } |
5392 | break; |
5393 | } |
5394 | |
5395 | default: |
5396 | break; |
5397 | } |
5398 | } |
5399 | |
5400 | void llvm::getGuaranteedNonPoisonOps(const Instruction *I, |
5401 | SmallPtrSetImpl<const Value *> &Operands) { |
5402 | getGuaranteedWellDefinedOps(I, Operands); |
5403 | switch (I->getOpcode()) { |
5404 | |
5405 | case Instruction::UDiv: |
5406 | case Instruction::SDiv: |
5407 | case Instruction::URem: |
5408 | case Instruction::SRem: |
5409 | Operands.insert(I->getOperand(1)); |
5410 | break; |
5411 | |
5412 | default: |
5413 | break; |
5414 | } |
5415 | } |
5416 | |
5417 | bool llvm::mustTriggerUB(const Instruction *I, |
5418 | const SmallSet<const Value *, 16>& KnownPoison) { |
5419 | SmallPtrSet<const Value *, 4> NonPoisonOps; |
5420 | getGuaranteedNonPoisonOps(I, NonPoisonOps); |
5421 | |
5422 | for (const auto *V : NonPoisonOps) |
5423 | if (KnownPoison.count(V)) |
5424 | return true; |
5425 | |
5426 | return false; |
5427 | } |
5428 | |
5429 | static bool programUndefinedIfUndefOrPoison(const Value *V, |
5430 | bool PoisonOnly) { |
5431 | |
5432 | |
5433 | |
5434 | |
5435 | |
5436 | |
5437 | |
5438 | const BasicBlock *BB = nullptr; |
5439 | BasicBlock::const_iterator Begin; |
5440 | if (const auto *Inst = dyn_cast<Instruction>(V)) { |
5441 | BB = Inst->getParent(); |
5442 | Begin = Inst->getIterator(); |
5443 | Begin++; |
5444 | } else if (const auto *Arg = dyn_cast<Argument>(V)) { |
5445 | BB = &Arg->getParent()->getEntryBlock(); |
5446 | Begin = BB->begin(); |
5447 | } else { |
5448 | return false; |
5449 | } |
5450 | |
5451 | |
5452 | |
5453 | unsigned ScanLimit = 32; |
5454 | BasicBlock::const_iterator End = BB->end(); |
5455 | |
5456 | if (!PoisonOnly) { |
5457 | |
5458 | |
5459 | |
5460 | |
5461 | for (auto &I : make_range(Begin, End)) { |
5462 | if (isa<DbgInfoIntrinsic>(I)) |
5463 | continue; |
5464 | if (--ScanLimit == 0) |
5465 | break; |
5466 | |
5467 | SmallPtrSet<const Value *, 4> WellDefinedOps; |
5468 | getGuaranteedWellDefinedOps(&I, WellDefinedOps); |
5469 | if (WellDefinedOps.contains(V)) |
5470 | return true; |
5471 | |
5472 | if (!isGuaranteedToTransferExecutionToSuccessor(&I)) |
5473 | break; |
5474 | } |
5475 | return false; |
5476 | } |
5477 | |
5478 | |
5479 | |
5480 | SmallSet<const Value *, 16> YieldsPoison; |
5481 | SmallSet<const BasicBlock *, 4> Visited; |
5482 | |
5483 | YieldsPoison.insert(V); |
5484 | auto Propagate = [&](const User *User) { |
5485 | if (propagatesPoison(cast<Operator>(User))) |
5486 | YieldsPoison.insert(User); |
5487 | }; |
5488 | for_each(V->users(), Propagate); |
5489 | Visited.insert(BB); |
5490 | |
5491 | while (true) { |
5492 | for (auto &I : make_range(Begin, End)) { |
5493 | if (isa<DbgInfoIntrinsic>(I)) |
5494 | continue; |
5495 | if (--ScanLimit == 0) |
5496 | return false; |
5497 | if (mustTriggerUB(&I, YieldsPoison)) |
5498 | return true; |
5499 | if (!isGuaranteedToTransferExecutionToSuccessor(&I)) |
5500 | return false; |
5501 | |
5502 | |
5503 | if (YieldsPoison.count(&I)) |
5504 | for_each(I.users(), Propagate); |
5505 | } |
5506 | |
5507 | BB = BB->getSingleSuccessor(); |
5508 | if (!BB || !Visited.insert(BB).second) |
5509 | break; |
5510 | |
5511 | Begin = BB->getFirstNonPHI()->getIterator(); |
5512 | End = BB->end(); |
5513 | } |
5514 | return false; |
5515 | } |
5516 | |
5517 | bool llvm::programUndefinedIfUndefOrPoison(const Instruction *Inst) { |
5518 | return ::programUndefinedIfUndefOrPoison(Inst, false); |
5519 | } |
5520 | |
5521 | bool llvm::programUndefinedIfPoison(const Instruction *Inst) { |
5522 | return ::programUndefinedIfUndefOrPoison(Inst, true); |
5523 | } |
5524 | |
5525 | static bool isKnownNonNaN(const Value *V, FastMathFlags FMF) { |
5526 | if (FMF.noNaNs()) |
5527 | return true; |
5528 | |
5529 | if (auto *C = dyn_cast<ConstantFP>(V)) |
5530 | return !C->isNaN(); |
5531 | |
5532 | if (auto *C = dyn_cast<ConstantDataVector>(V)) { |
5533 | if (!C->getElementType()->isFloatingPointTy()) |
5534 | return false; |
5535 | for (unsigned I = 0, E = C->getNumElements(); I < E; ++I) { |
5536 | if (C->getElementAsAPFloat(I).isNaN()) |
5537 | return false; |
5538 | } |
5539 | return true; |
5540 | } |
5541 | |
5542 | if (isa<ConstantAggregateZero>(V)) |
5543 | return true; |
5544 | |
5545 | return false; |
5546 | } |
5547 | |
5548 | static bool isKnownNonZero(const Value *V) { |
5549 | if (auto *C = dyn_cast<ConstantFP>(V)) |
5550 | return !C->isZero(); |
5551 | |
5552 | if (auto *C = dyn_cast<ConstantDataVector>(V)) { |
5553 | if (!C->getElementType()->isFloatingPointTy()) |
5554 | return false; |
5555 | for (unsigned I = 0, E = C->getNumElements(); I < E; ++I) { |
5556 | if (C->getElementAsAPFloat(I).isZero()) |
5557 | return false; |
5558 | } |
5559 | return true; |
5560 | } |
5561 | |
5562 | return false; |
5563 | } |
5564 | |
5565 | |
5566 | |
5567 | |
5568 | |
5569 | static SelectPatternResult matchFastFloatClamp(CmpInst::Predicate Pred, |
5570 | Value *CmpLHS, Value *CmpRHS, |
5571 | Value *TrueVal, Value *FalseVal, |
5572 | Value *&LHS, Value *&RHS) { |
5573 | |
5574 | |
5575 | |
5576 | |
5577 | |
5578 | |
5579 | if (CmpRHS == FalseVal) { |
5580 | std::swap(TrueVal, FalseVal); |
5581 | Pred = CmpInst::getInversePredicate(Pred); |
5582 | } |
5583 | |
5584 | |
5585 | LHS = TrueVal; |
5586 | RHS = FalseVal; |
5587 | |
5588 | const APFloat *FC1; |
5589 | if (CmpRHS != TrueVal || !match(CmpRHS, m_APFloat(FC1)) || !FC1->isFinite()) |
5590 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5591 | |
5592 | const APFloat *FC2; |
5593 | switch (Pred) { |
5594 | case CmpInst::FCMP_OLT: |
5595 | case CmpInst::FCMP_OLE: |
5596 | case CmpInst::FCMP_ULT: |
5597 | case CmpInst::FCMP_ULE: |
5598 | if (match(FalseVal, |
5599 | m_CombineOr(m_OrdFMin(m_Specific(CmpLHS), m_APFloat(FC2)), |
5600 | m_UnordFMin(m_Specific(CmpLHS), m_APFloat(FC2)))) && |
5601 | *FC1 < *FC2) |
5602 | return {SPF_FMAXNUM, SPNB_RETURNS_ANY, false}; |
5603 | break; |
5604 | case CmpInst::FCMP_OGT: |
5605 | case CmpInst::FCMP_OGE: |
5606 | case CmpInst::FCMP_UGT: |
5607 | case CmpInst::FCMP_UGE: |
5608 | if (match(FalseVal, |
5609 | m_CombineOr(m_OrdFMax(m_Specific(CmpLHS), m_APFloat(FC2)), |
5610 | m_UnordFMax(m_Specific(CmpLHS), m_APFloat(FC2)))) && |
5611 | *FC1 > *FC2) |
5612 | return {SPF_FMINNUM, SPNB_RETURNS_ANY, false}; |
5613 | break; |
5614 | default: |
5615 | break; |
5616 | } |
5617 | |
5618 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5619 | } |
5620 | |
5621 | |
5622 | |
5623 | static SelectPatternResult matchClamp(CmpInst::Predicate Pred, |
5624 | Value *CmpLHS, Value *CmpRHS, |
5625 | Value *TrueVal, Value *FalseVal) { |
5626 | |
5627 | if (CmpRHS != TrueVal) { |
5628 | Pred = ICmpInst::getSwappedPredicate(Pred); |
5629 | std::swap(TrueVal, FalseVal); |
5630 | } |
5631 | const APInt *C1; |
5632 | if (CmpRHS == TrueVal && match(CmpRHS, m_APInt(C1))) { |
5633 | const APInt *C2; |
5634 | |
5635 | if (match(FalseVal, m_SMin(m_Specific(CmpLHS), m_APInt(C2))) && |
5636 | C1->slt(*C2) && Pred == CmpInst::ICMP_SLT) |
5637 | return {SPF_SMAX, SPNB_NA, false}; |
5638 | |
5639 | |
5640 | if (match(FalseVal, m_SMax(m_Specific(CmpLHS), m_APInt(C2))) && |
5641 | C1->sgt(*C2) && Pred == CmpInst::ICMP_SGT) |
5642 | return {SPF_SMIN, SPNB_NA, false}; |
5643 | |
5644 | |
5645 | if (match(FalseVal, m_UMin(m_Specific(CmpLHS), m_APInt(C2))) && |
5646 | C1->ult(*C2) && Pred == CmpInst::ICMP_ULT) |
5647 | return {SPF_UMAX, SPNB_NA, false}; |
5648 | |
5649 | |
5650 | if (match(FalseVal, m_UMax(m_Specific(CmpLHS), m_APInt(C2))) && |
5651 | C1->ugt(*C2) && Pred == CmpInst::ICMP_UGT) |
5652 | return {SPF_UMIN, SPNB_NA, false}; |
5653 | } |
5654 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5655 | } |
5656 | |
5657 | |
5658 | |
5659 | static SelectPatternResult matchMinMaxOfMinMax(CmpInst::Predicate Pred, |
5660 | Value *CmpLHS, Value *CmpRHS, |
5661 | Value *TVal, Value *FVal, |
5662 | unsigned Depth) { |
5663 | |
5664 | assert(CmpInst::isIntPredicate(Pred) && "Expected integer comparison"); |
5665 | |
5666 | Value *A = nullptr, *B = nullptr; |
5667 | SelectPatternResult L = matchSelectPattern(TVal, A, B, nullptr, Depth + 1); |
5668 | if (!SelectPatternResult::isMinOrMax(L.Flavor)) |
5669 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5670 | |
5671 | Value *C = nullptr, *D = nullptr; |
5672 | SelectPatternResult R = matchSelectPattern(FVal, C, D, nullptr, Depth + 1); |
5673 | if (L.Flavor != R.Flavor) |
5674 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5675 | |
5676 | |
5677 | |
5678 | |
5679 | switch (L.Flavor) { |
5680 | case SPF_SMIN: |
5681 | if (Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SGE) { |
5682 | Pred = ICmpInst::getSwappedPredicate(Pred); |
5683 | std::swap(CmpLHS, CmpRHS); |
5684 | } |
5685 | if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SLE) |
5686 | break; |
5687 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5688 | case SPF_SMAX: |
5689 | if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SLE) { |
5690 | Pred = ICmpInst::getSwappedPredicate(Pred); |
5691 | std::swap(CmpLHS, CmpRHS); |
5692 | } |
5693 | if (Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SGE) |
5694 | break; |
5695 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5696 | case SPF_UMIN: |
5697 | if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_UGE) { |
5698 | Pred = ICmpInst::getSwappedPredicate(Pred); |
5699 | std::swap(CmpLHS, CmpRHS); |
5700 | } |
5701 | if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_ULE) |
5702 | break; |
5703 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5704 | case SPF_UMAX: |
5705 | if (Pred == ICmpInst::ICMP_ULT || Pred == ICmpInst::ICMP_ULE) { |
5706 | Pred = ICmpInst::getSwappedPredicate(Pred); |
5707 | std::swap(CmpLHS, CmpRHS); |
5708 | } |
5709 | if (Pred == ICmpInst::ICMP_UGT || Pred == ICmpInst::ICMP_UGE) |
5710 | break; |
5711 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5712 | default: |
5713 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5714 | } |
5715 | |
5716 | |
5717 | |
5718 | |
5719 | |
5720 | |
5721 | |
5722 | if (D == B) { |
5723 | if ((CmpLHS == A && CmpRHS == C) || (match(C, m_Not(m_Specific(CmpLHS))) && |
5724 | match(A, m_Not(m_Specific(CmpRHS))))) |
5725 | return {L.Flavor, SPNB_NA, false}; |
5726 | } |
5727 | |
5728 | |
5729 | if (C == B) { |
5730 | if ((CmpLHS == A && CmpRHS == D) || (match(D, m_Not(m_Specific(CmpLHS))) && |
5731 | match(A, m_Not(m_Specific(CmpRHS))))) |
5732 | return {L.Flavor, SPNB_NA, false}; |
5733 | } |
5734 | |
5735 | |
5736 | if (D == A) { |
5737 | if ((CmpLHS == B && CmpRHS == C) || (match(C, m_Not(m_Specific(CmpLHS))) && |
5738 | match(B, m_Not(m_Specific(CmpRHS))))) |
5739 | return {L.Flavor, SPNB_NA, false}; |
5740 | } |
5741 | |
5742 | |
5743 | if (C == A) { |
5744 | if ((CmpLHS == B && CmpRHS == D) || (match(D, m_Not(m_Specific(CmpLHS))) && |
5745 | match(B, m_Not(m_Specific(CmpRHS))))) |
5746 | return {L.Flavor, SPNB_NA, false}; |
5747 | } |
5748 | |
5749 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5750 | } |
5751 | |
5752 | |
5753 | |
5754 | |
5755 | static Value *getNotValue(Value *V) { |
5756 | Value *NotV; |
5757 | if (match(V, m_Not(m_Value(NotV)))) |
5758 | return NotV; |
5759 | |
5760 | const APInt *C; |
5761 | if (match(V, m_APInt(C))) |
5762 | return ConstantInt::get(V->getType(), ~(*C)); |
5763 | |
5764 | return nullptr; |
5765 | } |
5766 | |
5767 | |
5768 | static SelectPatternResult matchMinMax(CmpInst::Predicate Pred, |
5769 | Value *CmpLHS, Value *CmpRHS, |
5770 | Value *TrueVal, Value *FalseVal, |
5771 | Value *&LHS, Value *&RHS, |
5772 | unsigned Depth) { |
5773 | |
5774 | LHS = TrueVal; |
5775 | RHS = FalseVal; |
5776 | |
5777 | SelectPatternResult SPR = matchClamp(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal); |
5778 | if (SPR.Flavor != SelectPatternFlavor::SPF_UNKNOWN) |
5779 | return SPR; |
5780 | |
5781 | SPR = matchMinMaxOfMinMax(Pred, CmpLHS, CmpRHS, TrueVal, FalseVal, Depth); |
5782 | if (SPR.Flavor != SelectPatternFlavor::SPF_UNKNOWN) |
5783 | return SPR; |
5784 | |
5785 | |
5786 | |
5787 | |
5788 | if (CmpLHS == getNotValue(TrueVal) && CmpRHS == getNotValue(FalseVal)) { |
5789 | switch (Pred) { |
5790 | case CmpInst::ICMP_SGT: return {SPF_SMIN, SPNB_NA, false}; |
5791 | case CmpInst::ICMP_SLT: return {SPF_SMAX, SPNB_NA, false}; |
5792 | case CmpInst::ICMP_UGT: return {SPF_UMIN, SPNB_NA, false}; |
5793 | case CmpInst::ICMP_ULT: return {SPF_UMAX, SPNB_NA, false}; |
5794 | default: break; |
5795 | } |
5796 | } |
5797 | |
5798 | |
5799 | |
5800 | if (CmpLHS == getNotValue(FalseVal) && CmpRHS == getNotValue(TrueVal)) { |
5801 | switch (Pred) { |
5802 | case CmpInst::ICMP_SGT: return {SPF_SMAX, SPNB_NA, false}; |
5803 | case CmpInst::ICMP_SLT: return {SPF_SMIN, SPNB_NA, false}; |
5804 | case CmpInst::ICMP_UGT: return {SPF_UMAX, SPNB_NA, false}; |
5805 | case CmpInst::ICMP_ULT: return {SPF_UMIN, SPNB_NA, false}; |
5806 | default: break; |
5807 | } |
5808 | } |
5809 | |
5810 | if (Pred != CmpInst::ICMP_SGT && Pred != CmpInst::ICMP_SLT) |
5811 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5812 | |
5813 | |
5814 | |
5815 | |
5816 | if (match(TrueVal, m_Zero()) && |
5817 | match(FalseVal, m_NSWSub(m_Specific(CmpLHS), m_Specific(CmpRHS)))) |
5818 | return {Pred == CmpInst::ICMP_SGT ? SPF_SMIN : SPF_SMAX, SPNB_NA, false}; |
5819 | |
5820 | |
5821 | |
5822 | |
5823 | if (match(FalseVal, m_Zero()) && |
5824 | match(TrueVal, m_NSWSub(m_Specific(CmpLHS), m_Specific(CmpRHS)))) |
5825 | return {Pred == CmpInst::ICMP_SGT ? SPF_SMAX : SPF_SMIN, SPNB_NA, false}; |
5826 | |
5827 | const APInt *C1; |
5828 | if (!match(CmpRHS, m_APInt(C1))) |
5829 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5830 | |
5831 | |
5832 | const APInt *C2; |
5833 | if ((CmpLHS == TrueVal && match(FalseVal, m_APInt(C2))) || |
5834 | (CmpLHS == FalseVal && match(TrueVal, m_APInt(C2)))) { |
5835 | |
5836 | |
5837 | |
5838 | if (Pred == CmpInst::ICMP_SLT && C1->isNullValue() && |
5839 | C2->isMaxSignedValue()) |
5840 | return {CmpLHS == TrueVal ? SPF_UMAX : SPF_UMIN, SPNB_NA, false}; |
5841 | |
5842 | |
5843 | |
5844 | |
5845 | if (Pred == CmpInst::ICMP_SGT && C1->isAllOnesValue() && |
5846 | C2->isMinSignedValue()) |
5847 | return {CmpLHS == FalseVal ? SPF_UMAX : SPF_UMIN, SPNB_NA, false}; |
5848 | } |
5849 | |
5850 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5851 | } |
5852 | |
5853 | bool llvm::isKnownNegation(const Value *X, const Value *Y, bool NeedNSW) { |
5854 | assert(X && Y && "Invalid operand"); |
5855 | |
5856 | |
5857 | if ((!NeedNSW && match(X, m_Sub(m_ZeroInt(), m_Specific(Y)))) || |
5858 | (NeedNSW && match(X, m_NSWSub(m_ZeroInt(), m_Specific(Y))))) |
5859 | return true; |
5860 | |
5861 | |
5862 | if ((!NeedNSW && match(Y, m_Sub(m_ZeroInt(), m_Specific(X)))) || |
5863 | (NeedNSW && match(Y, m_NSWSub(m_ZeroInt(), m_Specific(X))))) |
5864 | return true; |
5865 | |
5866 | |
5867 | Value *A, *B; |
5868 | return (!NeedNSW && (match(X, m_Sub(m_Value(A), m_Value(B))) && |
5869 | match(Y, m_Sub(m_Specific(B), m_Specific(A))))) || |
5870 | (NeedNSW && (match(X, m_NSWSub(m_Value(A), m_Value(B))) && |
5871 | match(Y, m_NSWSub(m_Specific(B), m_Specific(A))))); |
5872 | } |
5873 | |
5874 | static SelectPatternResult matchSelectPattern(CmpInst::Predicate Pred, |
5875 | FastMathFlags FMF, |
5876 | Value *CmpLHS, Value *CmpRHS, |
5877 | Value *TrueVal, Value *FalseVal, |
5878 | Value *&LHS, Value *&RHS, |
5879 | unsigned Depth) { |
5880 | if (CmpInst::isFPPredicate(Pred)) { |
5881 | |
5882 | |
5883 | |
5884 | |
5885 | Value *OutputZeroVal = nullptr; |
5886 | if (match(TrueVal, m_AnyZeroFP()) && !match(FalseVal, m_AnyZeroFP()) && |
5887 | !cast<Constant>(TrueVal)->containsUndefOrPoisonElement()) |
5888 | OutputZeroVal = TrueVal; |
5889 | else if (match(FalseVal, m_AnyZeroFP()) && !match(TrueVal, m_AnyZeroFP()) && |
5890 | !cast<Constant>(FalseVal)->containsUndefOrPoisonElement()) |
5891 | OutputZeroVal = FalseVal; |
5892 | |
5893 | if (OutputZeroVal) { |
5894 | if (match(CmpLHS, m_AnyZeroFP())) |
5895 | CmpLHS = OutputZeroVal; |
5896 | if (match(CmpRHS, m_AnyZeroFP())) |
5897 | CmpRHS = OutputZeroVal; |
5898 | } |
5899 | } |
5900 | |
5901 | LHS = CmpLHS; |
5902 | RHS = CmpRHS; |
5903 | |
5904 | |
5905 | |
5906 | |
5907 | |
5908 | |
5909 | switch (Pred) { |
5910 | default: break; |
5911 | |
5912 | case CmpInst::FCMP_OGE: case CmpInst::FCMP_OLE: |
5913 | case CmpInst::FCMP_UGE: case CmpInst::FCMP_ULE: |
5914 | if (!FMF.noSignedZeros() && !isKnownNonZero(CmpLHS) && |
5915 | !isKnownNonZero(CmpRHS)) |
5916 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5917 | } |
5918 | |
5919 | SelectPatternNaNBehavior NaNBehavior = SPNB_NA; |
5920 | bool Ordered = false; |
5921 | |
5922 | |
5923 | |
5924 | |
5925 | |
5926 | |
5927 | if (CmpInst::isFPPredicate(Pred)) { |
5928 | bool LHSSafe = isKnownNonNaN(CmpLHS, FMF); |
5929 | bool RHSSafe = isKnownNonNaN(CmpRHS, FMF); |
5930 | |
5931 | if (LHSSafe && RHSSafe) { |
5932 | |
5933 | NaNBehavior = SPNB_RETURNS_ANY; |
5934 | } else if (CmpInst::isOrdered(Pred)) { |
5935 | |
5936 | |
5937 | Ordered = true; |
5938 | if (LHSSafe) |
5939 | |
5940 | NaNBehavior = SPNB_RETURNS_NAN; |
5941 | else if (RHSSafe) |
5942 | NaNBehavior = SPNB_RETURNS_OTHER; |
5943 | else |
5944 | |
5945 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5946 | } else { |
5947 | Ordered = false; |
5948 | |
5949 | |
5950 | if (LHSSafe) |
5951 | |
5952 | NaNBehavior = SPNB_RETURNS_OTHER; |
5953 | else if (RHSSafe) |
5954 | NaNBehavior = SPNB_RETURNS_NAN; |
5955 | else |
5956 | |
5957 | return {SPF_UNKNOWN, SPNB_NA, false}; |
5958 | } |
5959 | } |
5960 | |
5961 | if (Tru |