| File: | src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Transforms/Utils/LowerSwitch.cpp |
| Warning: | line 500, column 33 Called C++ object pointer is null |
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| 1 | //===- LowerSwitch.cpp - Eliminate Switch instructions --------------------===// | ||||
| 2 | // | ||||
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | ||||
| 4 | // See https://llvm.org/LICENSE.txt for license information. | ||||
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | ||||
| 6 | // | ||||
| 7 | //===----------------------------------------------------------------------===// | ||||
| 8 | // | ||||
| 9 | // The LowerSwitch transformation rewrites switch instructions with a sequence | ||||
| 10 | // of branches, which allows targets to get away with not implementing the | ||||
| 11 | // switch instruction until it is convenient. | ||||
| 12 | // | ||||
| 13 | //===----------------------------------------------------------------------===// | ||||
| 14 | |||||
| 15 | #include "llvm/Transforms/Utils/LowerSwitch.h" | ||||
| 16 | #include "llvm/ADT/DenseMap.h" | ||||
| 17 | #include "llvm/ADT/STLExtras.h" | ||||
| 18 | #include "llvm/ADT/SmallPtrSet.h" | ||||
| 19 | #include "llvm/ADT/SmallVector.h" | ||||
| 20 | #include "llvm/Analysis/AssumptionCache.h" | ||||
| 21 | #include "llvm/Analysis/LazyValueInfo.h" | ||||
| 22 | #include "llvm/Analysis/ValueTracking.h" | ||||
| 23 | #include "llvm/IR/BasicBlock.h" | ||||
| 24 | #include "llvm/IR/CFG.h" | ||||
| 25 | #include "llvm/IR/ConstantRange.h" | ||||
| 26 | #include "llvm/IR/Constants.h" | ||||
| 27 | #include "llvm/IR/Function.h" | ||||
| 28 | #include "llvm/IR/InstrTypes.h" | ||||
| 29 | #include "llvm/IR/Instructions.h" | ||||
| 30 | #include "llvm/IR/PassManager.h" | ||||
| 31 | #include "llvm/IR/Value.h" | ||||
| 32 | #include "llvm/InitializePasses.h" | ||||
| 33 | #include "llvm/Pass.h" | ||||
| 34 | #include "llvm/Support/Casting.h" | ||||
| 35 | #include "llvm/Support/Compiler.h" | ||||
| 36 | #include "llvm/Support/Debug.h" | ||||
| 37 | #include "llvm/Support/KnownBits.h" | ||||
| 38 | #include "llvm/Support/raw_ostream.h" | ||||
| 39 | #include "llvm/Transforms/Utils.h" | ||||
| 40 | #include "llvm/Transforms/Utils/BasicBlockUtils.h" | ||||
| 41 | #include <algorithm> | ||||
| 42 | #include <cassert> | ||||
| 43 | #include <cstdint> | ||||
| 44 | #include <iterator> | ||||
| 45 | #include <limits> | ||||
| 46 | #include <vector> | ||||
| 47 | |||||
| 48 | using namespace llvm; | ||||
| 49 | |||||
| 50 | #define DEBUG_TYPE"lower-switch" "lower-switch" | ||||
| 51 | |||||
| 52 | namespace { | ||||
| 53 | |||||
| 54 | struct IntRange { | ||||
| 55 | int64_t Low, High; | ||||
| 56 | }; | ||||
| 57 | |||||
| 58 | } // end anonymous namespace | ||||
| 59 | |||||
| 60 | namespace { | ||||
| 61 | // Return true iff R is covered by Ranges. | ||||
| 62 | bool IsInRanges(const IntRange &R, const std::vector<IntRange> &Ranges) { | ||||
| 63 | // Note: Ranges must be sorted, non-overlapping and non-adjacent. | ||||
| 64 | |||||
| 65 | // Find the first range whose High field is >= R.High, | ||||
| 66 | // then check if the Low field is <= R.Low. If so, we | ||||
| 67 | // have a Range that covers R. | ||||
| 68 | auto I = llvm::lower_bound( | ||||
| 69 | Ranges, R, [](IntRange A, IntRange B) { return A.High < B.High; }); | ||||
| 70 | return I != Ranges.end() && I->Low <= R.Low; | ||||
| 71 | } | ||||
| 72 | |||||
| 73 | struct CaseRange { | ||||
| 74 | ConstantInt *Low; | ||||
| 75 | ConstantInt *High; | ||||
| 76 | BasicBlock *BB; | ||||
| 77 | |||||
| 78 | CaseRange(ConstantInt *low, ConstantInt *high, BasicBlock *bb) | ||||
| 79 | : Low(low), High(high), BB(bb) {} | ||||
| 80 | }; | ||||
| 81 | |||||
| 82 | using CaseVector = std::vector<CaseRange>; | ||||
| 83 | using CaseItr = std::vector<CaseRange>::iterator; | ||||
| 84 | |||||
| 85 | /// The comparison function for sorting the switch case values in the vector. | ||||
| 86 | /// WARNING: Case ranges should be disjoint! | ||||
| 87 | struct CaseCmp { | ||||
| 88 | bool operator()(const CaseRange &C1, const CaseRange &C2) { | ||||
| 89 | const ConstantInt *CI1 = cast<const ConstantInt>(C1.Low); | ||||
| 90 | const ConstantInt *CI2 = cast<const ConstantInt>(C2.High); | ||||
| 91 | return CI1->getValue().slt(CI2->getValue()); | ||||
| 92 | } | ||||
| 93 | }; | ||||
| 94 | |||||
| 95 | /// Used for debugging purposes. | ||||
| 96 | LLVM_ATTRIBUTE_USED__attribute__((__used__)) | ||||
| 97 | raw_ostream &operator<<(raw_ostream &O, const CaseVector &C) { | ||||
| 98 | O << "["; | ||||
| 99 | |||||
| 100 | for (CaseVector::const_iterator B = C.begin(), E = C.end(); B != E;) { | ||||
| 101 | O << "[" << B->Low->getValue() << ", " << B->High->getValue() << "]"; | ||||
| 102 | if (++B != E) | ||||
| 103 | O << ", "; | ||||
| 104 | } | ||||
| 105 | |||||
| 106 | return O << "]"; | ||||
| 107 | } | ||||
| 108 | |||||
| 109 | /// Update the first occurrence of the "switch statement" BB in the PHI | ||||
| 110 | /// node with the "new" BB. The other occurrences will: | ||||
| 111 | /// | ||||
| 112 | /// 1) Be updated by subsequent calls to this function. Switch statements may | ||||
| 113 | /// have more than one outcoming edge into the same BB if they all have the same | ||||
| 114 | /// value. When the switch statement is converted these incoming edges are now | ||||
| 115 | /// coming from multiple BBs. | ||||
| 116 | /// 2) Removed if subsequent incoming values now share the same case, i.e., | ||||
| 117 | /// multiple outcome edges are condensed into one. This is necessary to keep the | ||||
| 118 | /// number of phi values equal to the number of branches to SuccBB. | ||||
| 119 | void FixPhis( | ||||
| 120 | BasicBlock *SuccBB, BasicBlock *OrigBB, BasicBlock *NewBB, | ||||
| 121 | const unsigned NumMergedCases = std::numeric_limits<unsigned>::max()) { | ||||
| 122 | for (BasicBlock::iterator I = SuccBB->begin(), | ||||
| 123 | IE = SuccBB->getFirstNonPHI()->getIterator(); | ||||
| 124 | I != IE; ++I) { | ||||
| 125 | PHINode *PN = cast<PHINode>(I); | ||||
| 126 | |||||
| 127 | // Only update the first occurrence. | ||||
| 128 | unsigned Idx = 0, E = PN->getNumIncomingValues(); | ||||
| 129 | unsigned LocalNumMergedCases = NumMergedCases; | ||||
| 130 | for (; Idx != E; ++Idx) { | ||||
| 131 | if (PN->getIncomingBlock(Idx) == OrigBB) { | ||||
| 132 | PN->setIncomingBlock(Idx, NewBB); | ||||
| 133 | break; | ||||
| 134 | } | ||||
| 135 | } | ||||
| 136 | |||||
| 137 | // Remove additional occurrences coming from condensed cases and keep the | ||||
| 138 | // number of incoming values equal to the number of branches to SuccBB. | ||||
| 139 | SmallVector<unsigned, 8> Indices; | ||||
| 140 | for (++Idx; LocalNumMergedCases > 0 && Idx < E; ++Idx) | ||||
| 141 | if (PN->getIncomingBlock(Idx) == OrigBB) { | ||||
| 142 | Indices.push_back(Idx); | ||||
| 143 | LocalNumMergedCases--; | ||||
| 144 | } | ||||
| 145 | // Remove incoming values in the reverse order to prevent invalidating | ||||
| 146 | // *successive* index. | ||||
| 147 | for (unsigned III : llvm::reverse(Indices)) | ||||
| 148 | PN->removeIncomingValue(III); | ||||
| 149 | } | ||||
| 150 | } | ||||
| 151 | |||||
| 152 | /// Create a new leaf block for the binary lookup tree. It checks if the | ||||
| 153 | /// switch's value == the case's value. If not, then it jumps to the default | ||||
| 154 | /// branch. At this point in the tree, the value can't be another valid case | ||||
| 155 | /// value, so the jump to the "default" branch is warranted. | ||||
| 156 | BasicBlock *NewLeafBlock(CaseRange &Leaf, Value *Val, ConstantInt *LowerBound, | ||||
| 157 | ConstantInt *UpperBound, BasicBlock *OrigBlock, | ||||
| 158 | BasicBlock *Default) { | ||||
| 159 | Function *F = OrigBlock->getParent(); | ||||
| 160 | BasicBlock *NewLeaf = BasicBlock::Create(Val->getContext(), "LeafBlock"); | ||||
| 161 | F->getBasicBlockList().insert(++OrigBlock->getIterator(), NewLeaf); | ||||
| 162 | |||||
| 163 | // Emit comparison | ||||
| 164 | ICmpInst *Comp = nullptr; | ||||
| 165 | if (Leaf.Low == Leaf.High) { | ||||
| 166 | // Make the seteq instruction... | ||||
| 167 | Comp = | ||||
| 168 | new ICmpInst(*NewLeaf, ICmpInst::ICMP_EQ, Val, Leaf.Low, "SwitchLeaf"); | ||||
| 169 | } else { | ||||
| 170 | // Make range comparison | ||||
| 171 | if (Leaf.Low == LowerBound) { | ||||
| 172 | // Val >= Min && Val <= Hi --> Val <= Hi | ||||
| 173 | Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_SLE, Val, Leaf.High, | ||||
| 174 | "SwitchLeaf"); | ||||
| 175 | } else if (Leaf.High == UpperBound) { | ||||
| 176 | // Val <= Max && Val >= Lo --> Val >= Lo | ||||
| 177 | Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_SGE, Val, Leaf.Low, | ||||
| 178 | "SwitchLeaf"); | ||||
| 179 | } else if (Leaf.Low->isZero()) { | ||||
| 180 | // Val >= 0 && Val <= Hi --> Val <=u Hi | ||||
| 181 | Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_ULE, Val, Leaf.High, | ||||
| 182 | "SwitchLeaf"); | ||||
| 183 | } else { | ||||
| 184 | // Emit V-Lo <=u Hi-Lo | ||||
| 185 | Constant *NegLo = ConstantExpr::getNeg(Leaf.Low); | ||||
| 186 | Instruction *Add = BinaryOperator::CreateAdd( | ||||
| 187 | Val, NegLo, Val->getName() + ".off", NewLeaf); | ||||
| 188 | Constant *UpperBound = ConstantExpr::getAdd(NegLo, Leaf.High); | ||||
| 189 | Comp = new ICmpInst(*NewLeaf, ICmpInst::ICMP_ULE, Add, UpperBound, | ||||
| 190 | "SwitchLeaf"); | ||||
| 191 | } | ||||
| 192 | } | ||||
| 193 | |||||
| 194 | // Make the conditional branch... | ||||
| 195 | BasicBlock *Succ = Leaf.BB; | ||||
| 196 | BranchInst::Create(Succ, Default, Comp, NewLeaf); | ||||
| 197 | |||||
| 198 | // If there were any PHI nodes in this successor, rewrite one entry | ||||
| 199 | // from OrigBlock to come from NewLeaf. | ||||
| 200 | for (BasicBlock::iterator I = Succ->begin(); isa<PHINode>(I); ++I) { | ||||
| 201 | PHINode *PN = cast<PHINode>(I); | ||||
| 202 | // Remove all but one incoming entries from the cluster | ||||
| 203 | uint64_t Range = Leaf.High->getSExtValue() - Leaf.Low->getSExtValue(); | ||||
| 204 | for (uint64_t j = 0; j < Range; ++j) { | ||||
| 205 | PN->removeIncomingValue(OrigBlock); | ||||
| 206 | } | ||||
| 207 | |||||
| 208 | int BlockIdx = PN->getBasicBlockIndex(OrigBlock); | ||||
| 209 | assert(BlockIdx != -1 && "Switch didn't go to this successor??")((void)0); | ||||
| 210 | PN->setIncomingBlock((unsigned)BlockIdx, NewLeaf); | ||||
| 211 | } | ||||
| 212 | |||||
| 213 | return NewLeaf; | ||||
| 214 | } | ||||
| 215 | |||||
| 216 | /// Convert the switch statement into a binary lookup of the case values. | ||||
| 217 | /// The function recursively builds this tree. LowerBound and UpperBound are | ||||
| 218 | /// used to keep track of the bounds for Val that have already been checked by | ||||
| 219 | /// a block emitted by one of the previous calls to switchConvert in the call | ||||
| 220 | /// stack. | ||||
| 221 | BasicBlock *SwitchConvert(CaseItr Begin, CaseItr End, ConstantInt *LowerBound, | ||||
| 222 | ConstantInt *UpperBound, Value *Val, | ||||
| 223 | BasicBlock *Predecessor, BasicBlock *OrigBlock, | ||||
| 224 | BasicBlock *Default, | ||||
| 225 | const std::vector<IntRange> &UnreachableRanges) { | ||||
| 226 | assert(LowerBound && UpperBound && "Bounds must be initialized")((void)0); | ||||
| 227 | unsigned Size = End - Begin; | ||||
| 228 | |||||
| 229 | if (Size == 1) { | ||||
| 230 | // Check if the Case Range is perfectly squeezed in between | ||||
| 231 | // already checked Upper and Lower bounds. If it is then we can avoid | ||||
| 232 | // emitting the code that checks if the value actually falls in the range | ||||
| 233 | // because the bounds already tell us so. | ||||
| 234 | if (Begin->Low == LowerBound && Begin->High == UpperBound) { | ||||
| 235 | unsigned NumMergedCases = 0; | ||||
| 236 | NumMergedCases = UpperBound->getSExtValue() - LowerBound->getSExtValue(); | ||||
| 237 | FixPhis(Begin->BB, OrigBlock, Predecessor, NumMergedCases); | ||||
| 238 | return Begin->BB; | ||||
| 239 | } | ||||
| 240 | return NewLeafBlock(*Begin, Val, LowerBound, UpperBound, OrigBlock, | ||||
| 241 | Default); | ||||
| 242 | } | ||||
| 243 | |||||
| 244 | unsigned Mid = Size / 2; | ||||
| 245 | std::vector<CaseRange> LHS(Begin, Begin + Mid); | ||||
| 246 | LLVM_DEBUG(dbgs() << "LHS: " << LHS << "\n")do { } while (false); | ||||
| 247 | std::vector<CaseRange> RHS(Begin + Mid, End); | ||||
| 248 | LLVM_DEBUG(dbgs() << "RHS: " << RHS << "\n")do { } while (false); | ||||
| 249 | |||||
| 250 | CaseRange &Pivot = *(Begin + Mid); | ||||
| 251 | LLVM_DEBUG(dbgs() << "Pivot ==> [" << Pivot.Low->getValue() << ", "do { } while (false) | ||||
| 252 | << Pivot.High->getValue() << "]\n")do { } while (false); | ||||
| 253 | |||||
| 254 | // NewLowerBound here should never be the integer minimal value. | ||||
| 255 | // This is because it is computed from a case range that is never | ||||
| 256 | // the smallest, so there is always a case range that has at least | ||||
| 257 | // a smaller value. | ||||
| 258 | ConstantInt *NewLowerBound = Pivot.Low; | ||||
| 259 | |||||
| 260 | // Because NewLowerBound is never the smallest representable integer | ||||
| 261 | // it is safe here to subtract one. | ||||
| 262 | ConstantInt *NewUpperBound = ConstantInt::get(NewLowerBound->getContext(), | ||||
| 263 | NewLowerBound->getValue() - 1); | ||||
| 264 | |||||
| 265 | if (!UnreachableRanges.empty()) { | ||||
| 266 | // Check if the gap between LHS's highest and NewLowerBound is unreachable. | ||||
| 267 | int64_t GapLow = LHS.back().High->getSExtValue() + 1; | ||||
| 268 | int64_t GapHigh = NewLowerBound->getSExtValue() - 1; | ||||
| 269 | IntRange Gap = { GapLow, GapHigh }; | ||||
| 270 | if (GapHigh >= GapLow && IsInRanges(Gap, UnreachableRanges)) | ||||
| 271 | NewUpperBound = LHS.back().High; | ||||
| 272 | } | ||||
| 273 | |||||
| 274 | LLVM_DEBUG(dbgs() << "LHS Bounds ==> [" << LowerBound->getSExtValue() << ", "do { } while (false) | ||||
| 275 | << NewUpperBound->getSExtValue() << "]\n"do { } while (false) | ||||
| 276 | << "RHS Bounds ==> [" << NewLowerBound->getSExtValue()do { } while (false) | ||||
| 277 | << ", " << UpperBound->getSExtValue() << "]\n")do { } while (false); | ||||
| 278 | |||||
| 279 | // Create a new node that checks if the value is < pivot. Go to the | ||||
| 280 | // left branch if it is and right branch if not. | ||||
| 281 | Function* F = OrigBlock->getParent(); | ||||
| 282 | BasicBlock* NewNode = BasicBlock::Create(Val->getContext(), "NodeBlock"); | ||||
| 283 | |||||
| 284 | ICmpInst* Comp = new ICmpInst(ICmpInst::ICMP_SLT, | ||||
| 285 | Val, Pivot.Low, "Pivot"); | ||||
| 286 | |||||
| 287 | BasicBlock *LBranch = | ||||
| 288 | SwitchConvert(LHS.begin(), LHS.end(), LowerBound, NewUpperBound, Val, | ||||
| 289 | NewNode, OrigBlock, Default, UnreachableRanges); | ||||
| 290 | BasicBlock *RBranch = | ||||
| 291 | SwitchConvert(RHS.begin(), RHS.end(), NewLowerBound, UpperBound, Val, | ||||
| 292 | NewNode, OrigBlock, Default, UnreachableRanges); | ||||
| 293 | |||||
| 294 | F->getBasicBlockList().insert(++OrigBlock->getIterator(), NewNode); | ||||
| 295 | NewNode->getInstList().push_back(Comp); | ||||
| 296 | |||||
| 297 | BranchInst::Create(LBranch, RBranch, Comp, NewNode); | ||||
| 298 | return NewNode; | ||||
| 299 | } | ||||
| 300 | |||||
| 301 | /// Transform simple list of \p SI's cases into list of CaseRange's \p Cases. | ||||
| 302 | /// \post \p Cases wouldn't contain references to \p SI's default BB. | ||||
| 303 | /// \returns Number of \p SI's cases that do not reference \p SI's default BB. | ||||
| 304 | unsigned Clusterify(CaseVector &Cases, SwitchInst *SI) { | ||||
| 305 | unsigned NumSimpleCases = 0; | ||||
| 306 | |||||
| 307 | // Start with "simple" cases | ||||
| 308 | for (auto Case : SI->cases()) { | ||||
| 309 | if (Case.getCaseSuccessor() == SI->getDefaultDest()) | ||||
| 310 | continue; | ||||
| 311 | Cases.push_back(CaseRange(Case.getCaseValue(), Case.getCaseValue(), | ||||
| 312 | Case.getCaseSuccessor())); | ||||
| 313 | ++NumSimpleCases; | ||||
| 314 | } | ||||
| 315 | |||||
| 316 | llvm::sort(Cases, CaseCmp()); | ||||
| 317 | |||||
| 318 | // Merge case into clusters | ||||
| 319 | if (Cases.size() >= 2) { | ||||
| 320 | CaseItr I = Cases.begin(); | ||||
| 321 | for (CaseItr J = std::next(I), E = Cases.end(); J != E; ++J) { | ||||
| 322 | int64_t nextValue = J->Low->getSExtValue(); | ||||
| 323 | int64_t currentValue = I->High->getSExtValue(); | ||||
| 324 | BasicBlock* nextBB = J->BB; | ||||
| 325 | BasicBlock* currentBB = I->BB; | ||||
| 326 | |||||
| 327 | // If the two neighboring cases go to the same destination, merge them | ||||
| 328 | // into a single case. | ||||
| 329 | assert(nextValue > currentValue && "Cases should be strictly ascending")((void)0); | ||||
| 330 | if ((nextValue == currentValue + 1) && (currentBB == nextBB)) { | ||||
| 331 | I->High = J->High; | ||||
| 332 | // FIXME: Combine branch weights. | ||||
| 333 | } else if (++I != J) { | ||||
| 334 | *I = *J; | ||||
| 335 | } | ||||
| 336 | } | ||||
| 337 | Cases.erase(std::next(I), Cases.end()); | ||||
| 338 | } | ||||
| 339 | |||||
| 340 | return NumSimpleCases; | ||||
| 341 | } | ||||
| 342 | |||||
| 343 | /// Replace the specified switch instruction with a sequence of chained if-then | ||||
| 344 | /// insts in a balanced binary search. | ||||
| 345 | void ProcessSwitchInst(SwitchInst *SI, | ||||
| 346 | SmallPtrSetImpl<BasicBlock *> &DeleteList, | ||||
| 347 | AssumptionCache *AC, LazyValueInfo *LVI) { | ||||
| 348 | BasicBlock *OrigBlock = SI->getParent(); | ||||
| 349 | Function *F = OrigBlock->getParent(); | ||||
| 350 | Value *Val = SI->getCondition(); // The value we are switching on... | ||||
| 351 | BasicBlock* Default = SI->getDefaultDest(); | ||||
| 352 | |||||
| 353 | // Don't handle unreachable blocks. If there are successors with phis, this | ||||
| 354 | // would leave them behind with missing predecessors. | ||||
| 355 | if ((OrigBlock != &F->getEntryBlock() && pred_empty(OrigBlock)) || | ||||
| 356 | OrigBlock->getSinglePredecessor() == OrigBlock) { | ||||
| 357 | DeleteList.insert(OrigBlock); | ||||
| 358 | return; | ||||
| 359 | } | ||||
| 360 | |||||
| 361 | // Prepare cases vector. | ||||
| 362 | CaseVector Cases; | ||||
| 363 | const unsigned NumSimpleCases = Clusterify(Cases, SI); | ||||
| 364 | LLVM_DEBUG(dbgs() << "Clusterify finished. Total clusters: " << Cases.size()do { } while (false) | ||||
| 365 | << ". Total non-default cases: " << NumSimpleCasesdo { } while (false) | ||||
| 366 | << "\nCase clusters: " << Cases << "\n")do { } while (false); | ||||
| 367 | |||||
| 368 | // If there is only the default destination, just branch. | ||||
| 369 | if (Cases.empty()) { | ||||
| 370 | BranchInst::Create(Default, OrigBlock); | ||||
| 371 | // Remove all the references from Default's PHIs to OrigBlock, but one. | ||||
| 372 | FixPhis(Default, OrigBlock, OrigBlock); | ||||
| 373 | SI->eraseFromParent(); | ||||
| 374 | return; | ||||
| 375 | } | ||||
| 376 | |||||
| 377 | ConstantInt *LowerBound = nullptr; | ||||
| 378 | ConstantInt *UpperBound = nullptr; | ||||
| 379 | bool DefaultIsUnreachableFromSwitch = false; | ||||
| 380 | |||||
| 381 | if (isa<UnreachableInst>(Default->getFirstNonPHIOrDbg())) { | ||||
| 382 | // Make the bounds tightly fitted around the case value range, because we | ||||
| 383 | // know that the value passed to the switch must be exactly one of the case | ||||
| 384 | // values. | ||||
| 385 | LowerBound = Cases.front().Low; | ||||
| 386 | UpperBound = Cases.back().High; | ||||
| 387 | DefaultIsUnreachableFromSwitch = true; | ||||
| 388 | } else { | ||||
| 389 | // Constraining the range of the value being switched over helps eliminating | ||||
| 390 | // unreachable BBs and minimizing the number of `add` instructions | ||||
| 391 | // newLeafBlock ends up emitting. Running CorrelatedValuePropagation after | ||||
| 392 | // LowerSwitch isn't as good, and also much more expensive in terms of | ||||
| 393 | // compile time for the following reasons: | ||||
| 394 | // 1. it processes many kinds of instructions, not just switches; | ||||
| 395 | // 2. even if limited to icmp instructions only, it will have to process | ||||
| 396 | // roughly C icmp's per switch, where C is the number of cases in the | ||||
| 397 | // switch, while LowerSwitch only needs to call LVI once per switch. | ||||
| 398 | const DataLayout &DL = F->getParent()->getDataLayout(); | ||||
| 399 | KnownBits Known = computeKnownBits(Val, DL, /*Depth=*/0, AC, SI); | ||||
| 400 | // TODO Shouldn't this create a signed range? | ||||
| 401 | ConstantRange KnownBitsRange = | ||||
| 402 | ConstantRange::fromKnownBits(Known, /*IsSigned=*/false); | ||||
| 403 | const ConstantRange LVIRange = LVI->getConstantRange(Val, SI); | ||||
| 404 | ConstantRange ValRange = KnownBitsRange.intersectWith(LVIRange); | ||||
| 405 | // We delegate removal of unreachable non-default cases to other passes. In | ||||
| 406 | // the unlikely event that some of them survived, we just conservatively | ||||
| 407 | // maintain the invariant that all the cases lie between the bounds. This | ||||
| 408 | // may, however, still render the default case effectively unreachable. | ||||
| 409 | APInt Low = Cases.front().Low->getValue(); | ||||
| 410 | APInt High = Cases.back().High->getValue(); | ||||
| 411 | APInt Min = APIntOps::smin(ValRange.getSignedMin(), Low); | ||||
| 412 | APInt Max = APIntOps::smax(ValRange.getSignedMax(), High); | ||||
| 413 | |||||
| 414 | LowerBound = ConstantInt::get(SI->getContext(), Min); | ||||
| 415 | UpperBound = ConstantInt::get(SI->getContext(), Max); | ||||
| 416 | DefaultIsUnreachableFromSwitch = (Min + (NumSimpleCases - 1) == Max); | ||||
| 417 | } | ||||
| 418 | |||||
| 419 | std::vector<IntRange> UnreachableRanges; | ||||
| 420 | |||||
| 421 | if (DefaultIsUnreachableFromSwitch) { | ||||
| 422 | DenseMap<BasicBlock *, unsigned> Popularity; | ||||
| 423 | unsigned MaxPop = 0; | ||||
| 424 | BasicBlock *PopSucc = nullptr; | ||||
| 425 | |||||
| 426 | IntRange R = {std::numeric_limits<int64_t>::min(), | ||||
| 427 | std::numeric_limits<int64_t>::max()}; | ||||
| 428 | UnreachableRanges.push_back(R); | ||||
| 429 | for (const auto &I : Cases) { | ||||
| 430 | int64_t Low = I.Low->getSExtValue(); | ||||
| 431 | int64_t High = I.High->getSExtValue(); | ||||
| 432 | |||||
| 433 | IntRange &LastRange = UnreachableRanges.back(); | ||||
| 434 | if (LastRange.Low == Low) { | ||||
| 435 | // There is nothing left of the previous range. | ||||
| 436 | UnreachableRanges.pop_back(); | ||||
| 437 | } else { | ||||
| 438 | // Terminate the previous range. | ||||
| 439 | assert(Low > LastRange.Low)((void)0); | ||||
| 440 | LastRange.High = Low - 1; | ||||
| 441 | } | ||||
| 442 | if (High != std::numeric_limits<int64_t>::max()) { | ||||
| 443 | IntRange R = { High + 1, std::numeric_limits<int64_t>::max() }; | ||||
| 444 | UnreachableRanges.push_back(R); | ||||
| 445 | } | ||||
| 446 | |||||
| 447 | // Count popularity. | ||||
| 448 | int64_t N = High - Low + 1; | ||||
| 449 | unsigned &Pop = Popularity[I.BB]; | ||||
| 450 | if ((Pop += N) > MaxPop) { | ||||
| 451 | MaxPop = Pop; | ||||
| 452 | PopSucc = I.BB; | ||||
| 453 | } | ||||
| 454 | } | ||||
| 455 | #ifndef NDEBUG1 | ||||
| 456 | /* UnreachableRanges should be sorted and the ranges non-adjacent. */ | ||||
| 457 | for (auto I = UnreachableRanges.begin(), E = UnreachableRanges.end(); | ||||
| 458 | I != E; ++I) { | ||||
| 459 | assert(I->Low <= I->High)((void)0); | ||||
| 460 | auto Next = I + 1; | ||||
| 461 | if (Next != E) { | ||||
| 462 | assert(Next->Low > I->High)((void)0); | ||||
| 463 | } | ||||
| 464 | } | ||||
| 465 | #endif | ||||
| 466 | |||||
| 467 | // As the default block in the switch is unreachable, update the PHI nodes | ||||
| 468 | // (remove all of the references to the default block) to reflect this. | ||||
| 469 | const unsigned NumDefaultEdges = SI->getNumCases() + 1 - NumSimpleCases; | ||||
| 470 | for (unsigned I = 0; I < NumDefaultEdges; ++I) | ||||
| 471 | Default->removePredecessor(OrigBlock); | ||||
| 472 | |||||
| 473 | // Use the most popular block as the new default, reducing the number of | ||||
| 474 | // cases. | ||||
| 475 | assert(MaxPop > 0 && PopSucc)((void)0); | ||||
| 476 | Default = PopSucc; | ||||
| 477 | llvm::erase_if(Cases, | ||||
| 478 | [PopSucc](const CaseRange &R) { return R.BB == PopSucc; }); | ||||
| 479 | |||||
| 480 | // If there are no cases left, just branch. | ||||
| 481 | if (Cases.empty()) { | ||||
| 482 | BranchInst::Create(Default, OrigBlock); | ||||
| 483 | SI->eraseFromParent(); | ||||
| 484 | // As all the cases have been replaced with a single branch, only keep | ||||
| 485 | // one entry in the PHI nodes. | ||||
| 486 | for (unsigned I = 0 ; I < (MaxPop - 1) ; ++I) | ||||
| 487 | PopSucc->removePredecessor(OrigBlock); | ||||
| 488 | return; | ||||
| 489 | } | ||||
| 490 | |||||
| 491 | // If the condition was a PHI node with the switch block as a predecessor | ||||
| 492 | // removing predecessors may have caused the condition to be erased. | ||||
| 493 | // Getting the condition value again here protects against that. | ||||
| 494 | Val = SI->getCondition(); | ||||
| 495 | } | ||||
| 496 | |||||
| 497 | // Create a new, empty default block so that the new hierarchy of | ||||
| 498 | // if-then statements go to this and the PHI nodes are happy. | ||||
| 499 | BasicBlock *NewDefault = BasicBlock::Create(SI->getContext(), "NewDefault"); | ||||
| 500 | F->getBasicBlockList().insert(Default->getIterator(), NewDefault); | ||||
| |||||
| 501 | BranchInst::Create(Default, NewDefault); | ||||
| 502 | |||||
| 503 | BasicBlock *SwitchBlock = | ||||
| 504 | SwitchConvert(Cases.begin(), Cases.end(), LowerBound, UpperBound, Val, | ||||
| 505 | OrigBlock, OrigBlock, NewDefault, UnreachableRanges); | ||||
| 506 | |||||
| 507 | // If there are entries in any PHI nodes for the default edge, make sure | ||||
| 508 | // to update them as well. | ||||
| 509 | FixPhis(Default, OrigBlock, NewDefault); | ||||
| 510 | |||||
| 511 | // Branch to our shiny new if-then stuff... | ||||
| 512 | BranchInst::Create(SwitchBlock, OrigBlock); | ||||
| 513 | |||||
| 514 | // We are now done with the switch instruction, delete it. | ||||
| 515 | BasicBlock *OldDefault = SI->getDefaultDest(); | ||||
| 516 | OrigBlock->getInstList().erase(SI); | ||||
| 517 | |||||
| 518 | // If the Default block has no more predecessors just add it to DeleteList. | ||||
| 519 | if (pred_empty(OldDefault)) | ||||
| 520 | DeleteList.insert(OldDefault); | ||||
| 521 | } | ||||
| 522 | |||||
| 523 | bool LowerSwitch(Function &F, LazyValueInfo *LVI, AssumptionCache *AC) { | ||||
| 524 | bool Changed = false; | ||||
| 525 | SmallPtrSet<BasicBlock *, 8> DeleteList; | ||||
| 526 | |||||
| 527 | for (Function::iterator I = F.begin(), E = F.end(); I != E;) { | ||||
| 528 | BasicBlock *Cur = | ||||
| 529 | &*I++; // Advance over block so we don't traverse new blocks | ||||
| 530 | |||||
| 531 | // If the block is a dead Default block that will be deleted later, don't | ||||
| 532 | // waste time processing it. | ||||
| 533 | if (DeleteList.count(Cur)) | ||||
| 534 | continue; | ||||
| 535 | |||||
| 536 | if (SwitchInst *SI
| ||||
| 537 | Changed = true; | ||||
| 538 | ProcessSwitchInst(SI, DeleteList, AC, LVI); | ||||
| 539 | } | ||||
| 540 | } | ||||
| 541 | |||||
| 542 | for (BasicBlock *BB : DeleteList) { | ||||
| 543 | LVI->eraseBlock(BB); | ||||
| 544 | DeleteDeadBlock(BB); | ||||
| 545 | } | ||||
| 546 | |||||
| 547 | return Changed; | ||||
| 548 | } | ||||
| 549 | |||||
| 550 | /// Replace all SwitchInst instructions with chained branch instructions. | ||||
| 551 | class LowerSwitchLegacyPass : public FunctionPass { | ||||
| 552 | public: | ||||
| 553 | // Pass identification, replacement for typeid | ||||
| 554 | static char ID; | ||||
| 555 | |||||
| 556 | LowerSwitchLegacyPass() : FunctionPass(ID) { | ||||
| 557 | initializeLowerSwitchLegacyPassPass(*PassRegistry::getPassRegistry()); | ||||
| 558 | } | ||||
| 559 | |||||
| 560 | bool runOnFunction(Function &F) override; | ||||
| 561 | |||||
| 562 | void getAnalysisUsage(AnalysisUsage &AU) const override { | ||||
| 563 | AU.addRequired<LazyValueInfoWrapperPass>(); | ||||
| 564 | } | ||||
| 565 | }; | ||||
| 566 | |||||
| 567 | } // end anonymous namespace | ||||
| 568 | |||||
| 569 | char LowerSwitchLegacyPass::ID = 0; | ||||
| 570 | |||||
| 571 | // Publicly exposed interface to pass... | ||||
| 572 | char &llvm::LowerSwitchID = LowerSwitchLegacyPass::ID; | ||||
| 573 | |||||
| 574 | INITIALIZE_PASS_BEGIN(LowerSwitchLegacyPass, "lowerswitch",static void *initializeLowerSwitchLegacyPassPassOnce(PassRegistry &Registry) { | ||||
| 575 | "Lower SwitchInst's to branches", false, false)static void *initializeLowerSwitchLegacyPassPassOnce(PassRegistry &Registry) { | ||||
| 576 | INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)initializeAssumptionCacheTrackerPass(Registry); | ||||
| 577 | INITIALIZE_PASS_DEPENDENCY(LazyValueInfoWrapperPass)initializeLazyValueInfoWrapperPassPass(Registry); | ||||
| 578 | INITIALIZE_PASS_END(LowerSwitchLegacyPass, "lowerswitch",PassInfo *PI = new PassInfo( "Lower SwitchInst's to branches" , "lowerswitch", &LowerSwitchLegacyPass::ID, PassInfo::NormalCtor_t (callDefaultCtor<LowerSwitchLegacyPass>), false, false) ; Registry.registerPass(*PI, true); return PI; } static llvm:: once_flag InitializeLowerSwitchLegacyPassPassFlag; void llvm:: initializeLowerSwitchLegacyPassPass(PassRegistry &Registry ) { llvm::call_once(InitializeLowerSwitchLegacyPassPassFlag, initializeLowerSwitchLegacyPassPassOnce , std::ref(Registry)); } | ||||
| 579 | "Lower SwitchInst's to branches", false, false)PassInfo *PI = new PassInfo( "Lower SwitchInst's to branches" , "lowerswitch", &LowerSwitchLegacyPass::ID, PassInfo::NormalCtor_t (callDefaultCtor<LowerSwitchLegacyPass>), false, false) ; Registry.registerPass(*PI, true); return PI; } static llvm:: once_flag InitializeLowerSwitchLegacyPassPassFlag; void llvm:: initializeLowerSwitchLegacyPassPass(PassRegistry &Registry ) { llvm::call_once(InitializeLowerSwitchLegacyPassPassFlag, initializeLowerSwitchLegacyPassPassOnce , std::ref(Registry)); } | ||||
| 580 | |||||
| 581 | // createLowerSwitchPass - Interface to this file... | ||||
| 582 | FunctionPass *llvm::createLowerSwitchPass() { | ||||
| 583 | return new LowerSwitchLegacyPass(); | ||||
| 584 | } | ||||
| 585 | |||||
| 586 | bool LowerSwitchLegacyPass::runOnFunction(Function &F) { | ||||
| 587 | LazyValueInfo *LVI = &getAnalysis<LazyValueInfoWrapperPass>().getLVI(); | ||||
| 588 | auto *ACT = getAnalysisIfAvailable<AssumptionCacheTracker>(); | ||||
| 589 | AssumptionCache *AC = ACT ? &ACT->getAssumptionCache(F) : nullptr; | ||||
| 590 | return LowerSwitch(F, LVI, AC); | ||||
| 591 | } | ||||
| 592 | |||||
| 593 | PreservedAnalyses LowerSwitchPass::run(Function &F, | ||||
| 594 | FunctionAnalysisManager &AM) { | ||||
| 595 | LazyValueInfo *LVI = &AM.getResult<LazyValueAnalysis>(F); | ||||
| 596 | AssumptionCache *AC = AM.getCachedResult<AssumptionAnalysis>(F); | ||||
| 597 | return LowerSwitch(F, LVI, AC) ? PreservedAnalyses::none() | ||||
| |||||
| 598 | : PreservedAnalyses::all(); | ||||
| 599 | } |
| 1 | //===-- llvm/ADT/APInt.h - For Arbitrary Precision Integer -----*- C++ -*--===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | /// |
| 9 | /// \file |
| 10 | /// This file implements a class to represent arbitrary precision |
| 11 | /// integral constant values and operations on them. |
| 12 | /// |
| 13 | //===----------------------------------------------------------------------===// |
| 14 | |
| 15 | #ifndef LLVM_ADT_APINT_H |
| 16 | #define LLVM_ADT_APINT_H |
| 17 | |
| 18 | #include "llvm/Support/Compiler.h" |
| 19 | #include "llvm/Support/MathExtras.h" |
| 20 | #include <cassert> |
| 21 | #include <climits> |
| 22 | #include <cstring> |
| 23 | #include <utility> |
| 24 | |
| 25 | namespace llvm { |
| 26 | class FoldingSetNodeID; |
| 27 | class StringRef; |
| 28 | class hash_code; |
| 29 | class raw_ostream; |
| 30 | |
| 31 | template <typename T> class SmallVectorImpl; |
| 32 | template <typename T> class ArrayRef; |
| 33 | template <typename T> class Optional; |
| 34 | template <typename T> struct DenseMapInfo; |
| 35 | |
| 36 | class APInt; |
| 37 | |
| 38 | inline APInt operator-(APInt); |
| 39 | |
| 40 | //===----------------------------------------------------------------------===// |
| 41 | // APInt Class |
| 42 | //===----------------------------------------------------------------------===// |
| 43 | |
| 44 | /// Class for arbitrary precision integers. |
| 45 | /// |
| 46 | /// APInt is a functional replacement for common case unsigned integer type like |
| 47 | /// "unsigned", "unsigned long" or "uint64_t", but also allows non-byte-width |
| 48 | /// integer sizes and large integer value types such as 3-bits, 15-bits, or more |
| 49 | /// than 64-bits of precision. APInt provides a variety of arithmetic operators |
| 50 | /// and methods to manipulate integer values of any bit-width. It supports both |
| 51 | /// the typical integer arithmetic and comparison operations as well as bitwise |
| 52 | /// manipulation. |
| 53 | /// |
| 54 | /// The class has several invariants worth noting: |
| 55 | /// * All bit, byte, and word positions are zero-based. |
| 56 | /// * Once the bit width is set, it doesn't change except by the Truncate, |
| 57 | /// SignExtend, or ZeroExtend operations. |
| 58 | /// * All binary operators must be on APInt instances of the same bit width. |
| 59 | /// Attempting to use these operators on instances with different bit |
| 60 | /// widths will yield an assertion. |
| 61 | /// * The value is stored canonically as an unsigned value. For operations |
| 62 | /// where it makes a difference, there are both signed and unsigned variants |
| 63 | /// of the operation. For example, sdiv and udiv. However, because the bit |
| 64 | /// widths must be the same, operations such as Mul and Add produce the same |
| 65 | /// results regardless of whether the values are interpreted as signed or |
| 66 | /// not. |
| 67 | /// * In general, the class tries to follow the style of computation that LLVM |
| 68 | /// uses in its IR. This simplifies its use for LLVM. |
| 69 | /// |
| 70 | class LLVM_NODISCARD[[clang::warn_unused_result]] APInt { |
| 71 | public: |
| 72 | typedef uint64_t WordType; |
| 73 | |
| 74 | /// This enum is used to hold the constants we needed for APInt. |
| 75 | enum : unsigned { |
| 76 | /// Byte size of a word. |
| 77 | APINT_WORD_SIZE = sizeof(WordType), |
| 78 | /// Bits in a word. |
| 79 | APINT_BITS_PER_WORD = APINT_WORD_SIZE * CHAR_BIT8 |
| 80 | }; |
| 81 | |
| 82 | enum class Rounding { |
| 83 | DOWN, |
| 84 | TOWARD_ZERO, |
| 85 | UP, |
| 86 | }; |
| 87 | |
| 88 | static constexpr WordType WORDTYPE_MAX = ~WordType(0); |
| 89 | |
| 90 | private: |
| 91 | /// This union is used to store the integer value. When the |
| 92 | /// integer bit-width <= 64, it uses VAL, otherwise it uses pVal. |
| 93 | union { |
| 94 | uint64_t VAL; ///< Used to store the <= 64 bits integer value. |
| 95 | uint64_t *pVal; ///< Used to store the >64 bits integer value. |
| 96 | } U; |
| 97 | |
| 98 | unsigned BitWidth; ///< The number of bits in this APInt. |
| 99 | |
| 100 | friend struct DenseMapInfo<APInt>; |
| 101 | |
| 102 | friend class APSInt; |
| 103 | |
| 104 | /// Fast internal constructor |
| 105 | /// |
| 106 | /// This constructor is used only internally for speed of construction of |
| 107 | /// temporaries. It is unsafe for general use so it is not public. |
| 108 | APInt(uint64_t *val, unsigned bits) : BitWidth(bits) { |
| 109 | U.pVal = val; |
| 110 | } |
| 111 | |
| 112 | /// Determine which word a bit is in. |
| 113 | /// |
| 114 | /// \returns the word position for the specified bit position. |
| 115 | static unsigned whichWord(unsigned bitPosition) { |
| 116 | return bitPosition / APINT_BITS_PER_WORD; |
| 117 | } |
| 118 | |
| 119 | /// Determine which bit in a word a bit is in. |
| 120 | /// |
| 121 | /// \returns the bit position in a word for the specified bit position |
| 122 | /// in the APInt. |
| 123 | static unsigned whichBit(unsigned bitPosition) { |
| 124 | return bitPosition % APINT_BITS_PER_WORD; |
| 125 | } |
| 126 | |
| 127 | /// Get a single bit mask. |
| 128 | /// |
| 129 | /// \returns a uint64_t with only bit at "whichBit(bitPosition)" set |
| 130 | /// This method generates and returns a uint64_t (word) mask for a single |
| 131 | /// bit at a specific bit position. This is used to mask the bit in the |
| 132 | /// corresponding word. |
| 133 | static uint64_t maskBit(unsigned bitPosition) { |
| 134 | return 1ULL << whichBit(bitPosition); |
| 135 | } |
| 136 | |
| 137 | /// Clear unused high order bits |
| 138 | /// |
| 139 | /// This method is used internally to clear the top "N" bits in the high order |
| 140 | /// word that are not used by the APInt. This is needed after the most |
| 141 | /// significant word is assigned a value to ensure that those bits are |
| 142 | /// zero'd out. |
| 143 | APInt &clearUnusedBits() { |
| 144 | // Compute how many bits are used in the final word |
| 145 | unsigned WordBits = ((BitWidth-1) % APINT_BITS_PER_WORD) + 1; |
| 146 | |
| 147 | // Mask out the high bits. |
| 148 | uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - WordBits); |
| 149 | if (isSingleWord()) |
| 150 | U.VAL &= mask; |
| 151 | else |
| 152 | U.pVal[getNumWords() - 1] &= mask; |
| 153 | return *this; |
| 154 | } |
| 155 | |
| 156 | /// Get the word corresponding to a bit position |
| 157 | /// \returns the corresponding word for the specified bit position. |
| 158 | uint64_t getWord(unsigned bitPosition) const { |
| 159 | return isSingleWord() ? U.VAL : U.pVal[whichWord(bitPosition)]; |
| 160 | } |
| 161 | |
| 162 | /// Utility method to change the bit width of this APInt to new bit width, |
| 163 | /// allocating and/or deallocating as necessary. There is no guarantee on the |
| 164 | /// value of any bits upon return. Caller should populate the bits after. |
| 165 | void reallocate(unsigned NewBitWidth); |
| 166 | |
| 167 | /// Convert a char array into an APInt |
| 168 | /// |
| 169 | /// \param radix 2, 8, 10, 16, or 36 |
| 170 | /// Converts a string into a number. The string must be non-empty |
| 171 | /// and well-formed as a number of the given base. The bit-width |
| 172 | /// must be sufficient to hold the result. |
| 173 | /// |
| 174 | /// This is used by the constructors that take string arguments. |
| 175 | /// |
| 176 | /// StringRef::getAsInteger is superficially similar but (1) does |
| 177 | /// not assume that the string is well-formed and (2) grows the |
| 178 | /// result to hold the input. |
| 179 | void fromString(unsigned numBits, StringRef str, uint8_t radix); |
| 180 | |
| 181 | /// An internal division function for dividing APInts. |
| 182 | /// |
| 183 | /// This is used by the toString method to divide by the radix. It simply |
| 184 | /// provides a more convenient form of divide for internal use since KnuthDiv |
| 185 | /// has specific constraints on its inputs. If those constraints are not met |
| 186 | /// then it provides a simpler form of divide. |
| 187 | static void divide(const WordType *LHS, unsigned lhsWords, |
| 188 | const WordType *RHS, unsigned rhsWords, WordType *Quotient, |
| 189 | WordType *Remainder); |
| 190 | |
| 191 | /// out-of-line slow case for inline constructor |
| 192 | void initSlowCase(uint64_t val, bool isSigned); |
| 193 | |
| 194 | /// shared code between two array constructors |
| 195 | void initFromArray(ArrayRef<uint64_t> array); |
| 196 | |
| 197 | /// out-of-line slow case for inline copy constructor |
| 198 | void initSlowCase(const APInt &that); |
| 199 | |
| 200 | /// out-of-line slow case for shl |
| 201 | void shlSlowCase(unsigned ShiftAmt); |
| 202 | |
| 203 | /// out-of-line slow case for lshr. |
| 204 | void lshrSlowCase(unsigned ShiftAmt); |
| 205 | |
| 206 | /// out-of-line slow case for ashr. |
| 207 | void ashrSlowCase(unsigned ShiftAmt); |
| 208 | |
| 209 | /// out-of-line slow case for operator= |
| 210 | void AssignSlowCase(const APInt &RHS); |
| 211 | |
| 212 | /// out-of-line slow case for operator== |
| 213 | bool EqualSlowCase(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__)); |
| 214 | |
| 215 | /// out-of-line slow case for countLeadingZeros |
| 216 | unsigned countLeadingZerosSlowCase() const LLVM_READONLY__attribute__((__pure__)); |
| 217 | |
| 218 | /// out-of-line slow case for countLeadingOnes. |
| 219 | unsigned countLeadingOnesSlowCase() const LLVM_READONLY__attribute__((__pure__)); |
| 220 | |
| 221 | /// out-of-line slow case for countTrailingZeros. |
| 222 | unsigned countTrailingZerosSlowCase() const LLVM_READONLY__attribute__((__pure__)); |
| 223 | |
| 224 | /// out-of-line slow case for countTrailingOnes |
| 225 | unsigned countTrailingOnesSlowCase() const LLVM_READONLY__attribute__((__pure__)); |
| 226 | |
| 227 | /// out-of-line slow case for countPopulation |
| 228 | unsigned countPopulationSlowCase() const LLVM_READONLY__attribute__((__pure__)); |
| 229 | |
| 230 | /// out-of-line slow case for intersects. |
| 231 | bool intersectsSlowCase(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__)); |
| 232 | |
| 233 | /// out-of-line slow case for isSubsetOf. |
| 234 | bool isSubsetOfSlowCase(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__)); |
| 235 | |
| 236 | /// out-of-line slow case for setBits. |
| 237 | void setBitsSlowCase(unsigned loBit, unsigned hiBit); |
| 238 | |
| 239 | /// out-of-line slow case for flipAllBits. |
| 240 | void flipAllBitsSlowCase(); |
| 241 | |
| 242 | /// out-of-line slow case for operator&=. |
| 243 | void AndAssignSlowCase(const APInt& RHS); |
| 244 | |
| 245 | /// out-of-line slow case for operator|=. |
| 246 | void OrAssignSlowCase(const APInt& RHS); |
| 247 | |
| 248 | /// out-of-line slow case for operator^=. |
| 249 | void XorAssignSlowCase(const APInt& RHS); |
| 250 | |
| 251 | /// Unsigned comparison. Returns -1, 0, or 1 if this APInt is less than, equal |
| 252 | /// to, or greater than RHS. |
| 253 | int compare(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__)); |
| 254 | |
| 255 | /// Signed comparison. Returns -1, 0, or 1 if this APInt is less than, equal |
| 256 | /// to, or greater than RHS. |
| 257 | int compareSigned(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__)); |
| 258 | |
| 259 | public: |
| 260 | /// \name Constructors |
| 261 | /// @{ |
| 262 | |
| 263 | /// Create a new APInt of numBits width, initialized as val. |
| 264 | /// |
| 265 | /// If isSigned is true then val is treated as if it were a signed value |
| 266 | /// (i.e. as an int64_t) and the appropriate sign extension to the bit width |
| 267 | /// will be done. Otherwise, no sign extension occurs (high order bits beyond |
| 268 | /// the range of val are zero filled). |
| 269 | /// |
| 270 | /// \param numBits the bit width of the constructed APInt |
| 271 | /// \param val the initial value of the APInt |
| 272 | /// \param isSigned how to treat signedness of val |
| 273 | APInt(unsigned numBits, uint64_t val, bool isSigned = false) |
| 274 | : BitWidth(numBits) { |
| 275 | assert(BitWidth && "bitwidth too small")((void)0); |
| 276 | if (isSingleWord()) { |
| 277 | U.VAL = val; |
| 278 | clearUnusedBits(); |
| 279 | } else { |
| 280 | initSlowCase(val, isSigned); |
| 281 | } |
| 282 | } |
| 283 | |
| 284 | /// Construct an APInt of numBits width, initialized as bigVal[]. |
| 285 | /// |
| 286 | /// Note that bigVal.size() can be smaller or larger than the corresponding |
| 287 | /// bit width but any extraneous bits will be dropped. |
| 288 | /// |
| 289 | /// \param numBits the bit width of the constructed APInt |
| 290 | /// \param bigVal a sequence of words to form the initial value of the APInt |
| 291 | APInt(unsigned numBits, ArrayRef<uint64_t> bigVal); |
| 292 | |
| 293 | /// Equivalent to APInt(numBits, ArrayRef<uint64_t>(bigVal, numWords)), but |
| 294 | /// deprecated because this constructor is prone to ambiguity with the |
| 295 | /// APInt(unsigned, uint64_t, bool) constructor. |
| 296 | /// |
| 297 | /// If this overload is ever deleted, care should be taken to prevent calls |
| 298 | /// from being incorrectly captured by the APInt(unsigned, uint64_t, bool) |
| 299 | /// constructor. |
| 300 | APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[]); |
| 301 | |
| 302 | /// Construct an APInt from a string representation. |
| 303 | /// |
| 304 | /// This constructor interprets the string \p str in the given radix. The |
| 305 | /// interpretation stops when the first character that is not suitable for the |
| 306 | /// radix is encountered, or the end of the string. Acceptable radix values |
| 307 | /// are 2, 8, 10, 16, and 36. It is an error for the value implied by the |
| 308 | /// string to require more bits than numBits. |
| 309 | /// |
| 310 | /// \param numBits the bit width of the constructed APInt |
| 311 | /// \param str the string to be interpreted |
| 312 | /// \param radix the radix to use for the conversion |
| 313 | APInt(unsigned numBits, StringRef str, uint8_t radix); |
| 314 | |
| 315 | /// Simply makes *this a copy of that. |
| 316 | /// Copy Constructor. |
| 317 | APInt(const APInt &that) : BitWidth(that.BitWidth) { |
| 318 | if (isSingleWord()) |
| 319 | U.VAL = that.U.VAL; |
| 320 | else |
| 321 | initSlowCase(that); |
| 322 | } |
| 323 | |
| 324 | /// Move Constructor. |
| 325 | APInt(APInt &&that) : BitWidth(that.BitWidth) { |
| 326 | memcpy(&U, &that.U, sizeof(U)); |
| 327 | that.BitWidth = 0; |
| 328 | } |
| 329 | |
| 330 | /// Destructor. |
| 331 | ~APInt() { |
| 332 | if (needsCleanup()) |
| 333 | delete[] U.pVal; |
| 334 | } |
| 335 | |
| 336 | /// Default constructor that creates an uninteresting APInt |
| 337 | /// representing a 1-bit zero value. |
| 338 | /// |
| 339 | /// This is useful for object deserialization (pair this with the static |
| 340 | /// method Read). |
| 341 | explicit APInt() : BitWidth(1) { U.VAL = 0; } |
| 342 | |
| 343 | /// Returns whether this instance allocated memory. |
| 344 | bool needsCleanup() const { return !isSingleWord(); } |
| 345 | |
| 346 | /// Used to insert APInt objects, or objects that contain APInt objects, into |
| 347 | /// FoldingSets. |
| 348 | void Profile(FoldingSetNodeID &id) const; |
| 349 | |
| 350 | /// @} |
| 351 | /// \name Value Tests |
| 352 | /// @{ |
| 353 | |
| 354 | /// Determine if this APInt just has one word to store value. |
| 355 | /// |
| 356 | /// \returns true if the number of bits <= 64, false otherwise. |
| 357 | bool isSingleWord() const { return BitWidth <= APINT_BITS_PER_WORD; } |
| 358 | |
| 359 | /// Determine sign of this APInt. |
| 360 | /// |
| 361 | /// This tests the high bit of this APInt to determine if it is set. |
| 362 | /// |
| 363 | /// \returns true if this APInt is negative, false otherwise |
| 364 | bool isNegative() const { return (*this)[BitWidth - 1]; } |
| 365 | |
| 366 | /// Determine if this APInt Value is non-negative (>= 0) |
| 367 | /// |
| 368 | /// This tests the high bit of the APInt to determine if it is unset. |
| 369 | bool isNonNegative() const { return !isNegative(); } |
| 370 | |
| 371 | /// Determine if sign bit of this APInt is set. |
| 372 | /// |
| 373 | /// This tests the high bit of this APInt to determine if it is set. |
| 374 | /// |
| 375 | /// \returns true if this APInt has its sign bit set, false otherwise. |
| 376 | bool isSignBitSet() const { return (*this)[BitWidth-1]; } |
| 377 | |
| 378 | /// Determine if sign bit of this APInt is clear. |
| 379 | /// |
| 380 | /// This tests the high bit of this APInt to determine if it is clear. |
| 381 | /// |
| 382 | /// \returns true if this APInt has its sign bit clear, false otherwise. |
| 383 | bool isSignBitClear() const { return !isSignBitSet(); } |
| 384 | |
| 385 | /// Determine if this APInt Value is positive. |
| 386 | /// |
| 387 | /// This tests if the value of this APInt is positive (> 0). Note |
| 388 | /// that 0 is not a positive value. |
| 389 | /// |
| 390 | /// \returns true if this APInt is positive. |
| 391 | bool isStrictlyPositive() const { return isNonNegative() && !isNullValue(); } |
| 392 | |
| 393 | /// Determine if this APInt Value is non-positive (<= 0). |
| 394 | /// |
| 395 | /// \returns true if this APInt is non-positive. |
| 396 | bool isNonPositive() const { return !isStrictlyPositive(); } |
| 397 | |
| 398 | /// Determine if all bits are set |
| 399 | /// |
| 400 | /// This checks to see if the value has all bits of the APInt are set or not. |
| 401 | bool isAllOnesValue() const { |
| 402 | if (isSingleWord()) |
| 403 | return U.VAL == WORDTYPE_MAX >> (APINT_BITS_PER_WORD - BitWidth); |
| 404 | return countTrailingOnesSlowCase() == BitWidth; |
| 405 | } |
| 406 | |
| 407 | /// Determine if all bits are clear |
| 408 | /// |
| 409 | /// This checks to see if the value has all bits of the APInt are clear or |
| 410 | /// not. |
| 411 | bool isNullValue() const { return !*this; } |
| 412 | |
| 413 | /// Determine if this is a value of 1. |
| 414 | /// |
| 415 | /// This checks to see if the value of this APInt is one. |
| 416 | bool isOneValue() const { |
| 417 | if (isSingleWord()) |
| 418 | return U.VAL == 1; |
| 419 | return countLeadingZerosSlowCase() == BitWidth - 1; |
| 420 | } |
| 421 | |
| 422 | /// Determine if this is the largest unsigned value. |
| 423 | /// |
| 424 | /// This checks to see if the value of this APInt is the maximum unsigned |
| 425 | /// value for the APInt's bit width. |
| 426 | bool isMaxValue() const { return isAllOnesValue(); } |
| 427 | |
| 428 | /// Determine if this is the largest signed value. |
| 429 | /// |
| 430 | /// This checks to see if the value of this APInt is the maximum signed |
| 431 | /// value for the APInt's bit width. |
| 432 | bool isMaxSignedValue() const { |
| 433 | if (isSingleWord()) |
| 434 | return U.VAL == ((WordType(1) << (BitWidth - 1)) - 1); |
| 435 | return !isNegative() && countTrailingOnesSlowCase() == BitWidth - 1; |
| 436 | } |
| 437 | |
| 438 | /// Determine if this is the smallest unsigned value. |
| 439 | /// |
| 440 | /// This checks to see if the value of this APInt is the minimum unsigned |
| 441 | /// value for the APInt's bit width. |
| 442 | bool isMinValue() const { return isNullValue(); } |
| 443 | |
| 444 | /// Determine if this is the smallest signed value. |
| 445 | /// |
| 446 | /// This checks to see if the value of this APInt is the minimum signed |
| 447 | /// value for the APInt's bit width. |
| 448 | bool isMinSignedValue() const { |
| 449 | if (isSingleWord()) |
| 450 | return U.VAL == (WordType(1) << (BitWidth - 1)); |
| 451 | return isNegative() && countTrailingZerosSlowCase() == BitWidth - 1; |
| 452 | } |
| 453 | |
| 454 | /// Check if this APInt has an N-bits unsigned integer value. |
| 455 | bool isIntN(unsigned N) const { |
| 456 | assert(N && "N == 0 ???")((void)0); |
| 457 | return getActiveBits() <= N; |
| 458 | } |
| 459 | |
| 460 | /// Check if this APInt has an N-bits signed integer value. |
| 461 | bool isSignedIntN(unsigned N) const { |
| 462 | assert(N && "N == 0 ???")((void)0); |
| 463 | return getMinSignedBits() <= N; |
| 464 | } |
| 465 | |
| 466 | /// Check if this APInt's value is a power of two greater than zero. |
| 467 | /// |
| 468 | /// \returns true if the argument APInt value is a power of two > 0. |
| 469 | bool isPowerOf2() const { |
| 470 | if (isSingleWord()) |
| 471 | return isPowerOf2_64(U.VAL); |
| 472 | return countPopulationSlowCase() == 1; |
| 473 | } |
| 474 | |
| 475 | /// Check if the APInt's value is returned by getSignMask. |
| 476 | /// |
| 477 | /// \returns true if this is the value returned by getSignMask. |
| 478 | bool isSignMask() const { return isMinSignedValue(); } |
| 479 | |
| 480 | /// Convert APInt to a boolean value. |
| 481 | /// |
| 482 | /// This converts the APInt to a boolean value as a test against zero. |
| 483 | bool getBoolValue() const { return !!*this; } |
| 484 | |
| 485 | /// If this value is smaller than the specified limit, return it, otherwise |
| 486 | /// return the limit value. This causes the value to saturate to the limit. |
| 487 | uint64_t getLimitedValue(uint64_t Limit = UINT64_MAX0xffffffffffffffffULL) const { |
| 488 | return ugt(Limit) ? Limit : getZExtValue(); |
| 489 | } |
| 490 | |
| 491 | /// Check if the APInt consists of a repeated bit pattern. |
| 492 | /// |
| 493 | /// e.g. 0x01010101 satisfies isSplat(8). |
| 494 | /// \param SplatSizeInBits The size of the pattern in bits. Must divide bit |
| 495 | /// width without remainder. |
| 496 | bool isSplat(unsigned SplatSizeInBits) const; |
| 497 | |
| 498 | /// \returns true if this APInt value is a sequence of \param numBits ones |
| 499 | /// starting at the least significant bit with the remainder zero. |
| 500 | bool isMask(unsigned numBits) const { |
| 501 | assert(numBits != 0 && "numBits must be non-zero")((void)0); |
| 502 | assert(numBits <= BitWidth && "numBits out of range")((void)0); |
| 503 | if (isSingleWord()) |
| 504 | return U.VAL == (WORDTYPE_MAX >> (APINT_BITS_PER_WORD - numBits)); |
| 505 | unsigned Ones = countTrailingOnesSlowCase(); |
| 506 | return (numBits == Ones) && |
| 507 | ((Ones + countLeadingZerosSlowCase()) == BitWidth); |
| 508 | } |
| 509 | |
| 510 | /// \returns true if this APInt is a non-empty sequence of ones starting at |
| 511 | /// the least significant bit with the remainder zero. |
| 512 | /// Ex. isMask(0x0000FFFFU) == true. |
| 513 | bool isMask() const { |
| 514 | if (isSingleWord()) |
| 515 | return isMask_64(U.VAL); |
| 516 | unsigned Ones = countTrailingOnesSlowCase(); |
| 517 | return (Ones > 0) && ((Ones + countLeadingZerosSlowCase()) == BitWidth); |
| 518 | } |
| 519 | |
| 520 | /// Return true if this APInt value contains a sequence of ones with |
| 521 | /// the remainder zero. |
| 522 | bool isShiftedMask() const { |
| 523 | if (isSingleWord()) |
| 524 | return isShiftedMask_64(U.VAL); |
| 525 | unsigned Ones = countPopulationSlowCase(); |
| 526 | unsigned LeadZ = countLeadingZerosSlowCase(); |
| 527 | return (Ones + LeadZ + countTrailingZeros()) == BitWidth; |
| 528 | } |
| 529 | |
| 530 | /// @} |
| 531 | /// \name Value Generators |
| 532 | /// @{ |
| 533 | |
| 534 | /// Gets maximum unsigned value of APInt for specific bit width. |
| 535 | static APInt getMaxValue(unsigned numBits) { |
| 536 | return getAllOnesValue(numBits); |
| 537 | } |
| 538 | |
| 539 | /// Gets maximum signed value of APInt for a specific bit width. |
| 540 | static APInt getSignedMaxValue(unsigned numBits) { |
| 541 | APInt API = getAllOnesValue(numBits); |
| 542 | API.clearBit(numBits - 1); |
| 543 | return API; |
| 544 | } |
| 545 | |
| 546 | /// Gets minimum unsigned value of APInt for a specific bit width. |
| 547 | static APInt getMinValue(unsigned numBits) { return APInt(numBits, 0); } |
| 548 | |
| 549 | /// Gets minimum signed value of APInt for a specific bit width. |
| 550 | static APInt getSignedMinValue(unsigned numBits) { |
| 551 | APInt API(numBits, 0); |
| 552 | API.setBit(numBits - 1); |
| 553 | return API; |
| 554 | } |
| 555 | |
| 556 | /// Get the SignMask for a specific bit width. |
| 557 | /// |
| 558 | /// This is just a wrapper function of getSignedMinValue(), and it helps code |
| 559 | /// readability when we want to get a SignMask. |
| 560 | static APInt getSignMask(unsigned BitWidth) { |
| 561 | return getSignedMinValue(BitWidth); |
| 562 | } |
| 563 | |
| 564 | /// Get the all-ones value. |
| 565 | /// |
| 566 | /// \returns the all-ones value for an APInt of the specified bit-width. |
| 567 | static APInt getAllOnesValue(unsigned numBits) { |
| 568 | return APInt(numBits, WORDTYPE_MAX, true); |
| 569 | } |
| 570 | |
| 571 | /// Get the '0' value. |
| 572 | /// |
| 573 | /// \returns the '0' value for an APInt of the specified bit-width. |
| 574 | static APInt getNullValue(unsigned numBits) { return APInt(numBits, 0); } |
| 575 | |
| 576 | /// Compute an APInt containing numBits highbits from this APInt. |
| 577 | /// |
| 578 | /// Get an APInt with the same BitWidth as this APInt, just zero mask |
| 579 | /// the low bits and right shift to the least significant bit. |
| 580 | /// |
| 581 | /// \returns the high "numBits" bits of this APInt. |
| 582 | APInt getHiBits(unsigned numBits) const; |
| 583 | |
| 584 | /// Compute an APInt containing numBits lowbits from this APInt. |
| 585 | /// |
| 586 | /// Get an APInt with the same BitWidth as this APInt, just zero mask |
| 587 | /// the high bits. |
| 588 | /// |
| 589 | /// \returns the low "numBits" bits of this APInt. |
| 590 | APInt getLoBits(unsigned numBits) const; |
| 591 | |
| 592 | /// Return an APInt with exactly one bit set in the result. |
| 593 | static APInt getOneBitSet(unsigned numBits, unsigned BitNo) { |
| 594 | APInt Res(numBits, 0); |
| 595 | Res.setBit(BitNo); |
| 596 | return Res; |
| 597 | } |
| 598 | |
| 599 | /// Get a value with a block of bits set. |
| 600 | /// |
| 601 | /// Constructs an APInt value that has a contiguous range of bits set. The |
| 602 | /// bits from loBit (inclusive) to hiBit (exclusive) will be set. All other |
| 603 | /// bits will be zero. For example, with parameters(32, 0, 16) you would get |
| 604 | /// 0x0000FFFF. Please call getBitsSetWithWrap if \p loBit may be greater than |
| 605 | /// \p hiBit. |
| 606 | /// |
| 607 | /// \param numBits the intended bit width of the result |
| 608 | /// \param loBit the index of the lowest bit set. |
| 609 | /// \param hiBit the index of the highest bit set. |
| 610 | /// |
| 611 | /// \returns An APInt value with the requested bits set. |
| 612 | static APInt getBitsSet(unsigned numBits, unsigned loBit, unsigned hiBit) { |
| 613 | assert(loBit <= hiBit && "loBit greater than hiBit")((void)0); |
| 614 | APInt Res(numBits, 0); |
| 615 | Res.setBits(loBit, hiBit); |
| 616 | return Res; |
| 617 | } |
| 618 | |
| 619 | /// Wrap version of getBitsSet. |
| 620 | /// If \p hiBit is bigger than \p loBit, this is same with getBitsSet. |
| 621 | /// If \p hiBit is not bigger than \p loBit, the set bits "wrap". For example, |
| 622 | /// with parameters (32, 28, 4), you would get 0xF000000F. |
| 623 | /// If \p hiBit is equal to \p loBit, you would get a result with all bits |
| 624 | /// set. |
| 625 | static APInt getBitsSetWithWrap(unsigned numBits, unsigned loBit, |
| 626 | unsigned hiBit) { |
| 627 | APInt Res(numBits, 0); |
| 628 | Res.setBitsWithWrap(loBit, hiBit); |
| 629 | return Res; |
| 630 | } |
| 631 | |
| 632 | /// Get a value with upper bits starting at loBit set. |
| 633 | /// |
| 634 | /// Constructs an APInt value that has a contiguous range of bits set. The |
| 635 | /// bits from loBit (inclusive) to numBits (exclusive) will be set. All other |
| 636 | /// bits will be zero. For example, with parameters(32, 12) you would get |
| 637 | /// 0xFFFFF000. |
| 638 | /// |
| 639 | /// \param numBits the intended bit width of the result |
| 640 | /// \param loBit the index of the lowest bit to set. |
| 641 | /// |
| 642 | /// \returns An APInt value with the requested bits set. |
| 643 | static APInt getBitsSetFrom(unsigned numBits, unsigned loBit) { |
| 644 | APInt Res(numBits, 0); |
| 645 | Res.setBitsFrom(loBit); |
| 646 | return Res; |
| 647 | } |
| 648 | |
| 649 | /// Get a value with high bits set |
| 650 | /// |
| 651 | /// Constructs an APInt value that has the top hiBitsSet bits set. |
| 652 | /// |
| 653 | /// \param numBits the bitwidth of the result |
| 654 | /// \param hiBitsSet the number of high-order bits set in the result. |
| 655 | static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet) { |
| 656 | APInt Res(numBits, 0); |
| 657 | Res.setHighBits(hiBitsSet); |
| 658 | return Res; |
| 659 | } |
| 660 | |
| 661 | /// Get a value with low bits set |
| 662 | /// |
| 663 | /// Constructs an APInt value that has the bottom loBitsSet bits set. |
| 664 | /// |
| 665 | /// \param numBits the bitwidth of the result |
| 666 | /// \param loBitsSet the number of low-order bits set in the result. |
| 667 | static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet) { |
| 668 | APInt Res(numBits, 0); |
| 669 | Res.setLowBits(loBitsSet); |
| 670 | return Res; |
| 671 | } |
| 672 | |
| 673 | /// Return a value containing V broadcasted over NewLen bits. |
| 674 | static APInt getSplat(unsigned NewLen, const APInt &V); |
| 675 | |
| 676 | /// Determine if two APInts have the same value, after zero-extending |
| 677 | /// one of them (if needed!) to ensure that the bit-widths match. |
| 678 | static bool isSameValue(const APInt &I1, const APInt &I2) { |
| 679 | if (I1.getBitWidth() == I2.getBitWidth()) |
| 680 | return I1 == I2; |
| 681 | |
| 682 | if (I1.getBitWidth() > I2.getBitWidth()) |
| 683 | return I1 == I2.zext(I1.getBitWidth()); |
| 684 | |
| 685 | return I1.zext(I2.getBitWidth()) == I2; |
| 686 | } |
| 687 | |
| 688 | /// Overload to compute a hash_code for an APInt value. |
| 689 | friend hash_code hash_value(const APInt &Arg); |
| 690 | |
| 691 | /// This function returns a pointer to the internal storage of the APInt. |
| 692 | /// This is useful for writing out the APInt in binary form without any |
| 693 | /// conversions. |
| 694 | const uint64_t *getRawData() const { |
| 695 | if (isSingleWord()) |
| 696 | return &U.VAL; |
| 697 | return &U.pVal[0]; |
| 698 | } |
| 699 | |
| 700 | /// @} |
| 701 | /// \name Unary Operators |
| 702 | /// @{ |
| 703 | |
| 704 | /// Postfix increment operator. |
| 705 | /// |
| 706 | /// Increments *this by 1. |
| 707 | /// |
| 708 | /// \returns a new APInt value representing the original value of *this. |
| 709 | const APInt operator++(int) { |
| 710 | APInt API(*this); |
| 711 | ++(*this); |
| 712 | return API; |
| 713 | } |
| 714 | |
| 715 | /// Prefix increment operator. |
| 716 | /// |
| 717 | /// \returns *this incremented by one |
| 718 | APInt &operator++(); |
| 719 | |
| 720 | /// Postfix decrement operator. |
| 721 | /// |
| 722 | /// Decrements *this by 1. |
| 723 | /// |
| 724 | /// \returns a new APInt value representing the original value of *this. |
| 725 | const APInt operator--(int) { |
| 726 | APInt API(*this); |
| 727 | --(*this); |
| 728 | return API; |
| 729 | } |
| 730 | |
| 731 | /// Prefix decrement operator. |
| 732 | /// |
| 733 | /// \returns *this decremented by one. |
| 734 | APInt &operator--(); |
| 735 | |
| 736 | /// Logical negation operator. |
| 737 | /// |
| 738 | /// Performs logical negation operation on this APInt. |
| 739 | /// |
| 740 | /// \returns true if *this is zero, false otherwise. |
| 741 | bool operator!() const { |
| 742 | if (isSingleWord()) |
| 743 | return U.VAL == 0; |
| 744 | return countLeadingZerosSlowCase() == BitWidth; |
| 745 | } |
| 746 | |
| 747 | /// @} |
| 748 | /// \name Assignment Operators |
| 749 | /// @{ |
| 750 | |
| 751 | /// Copy assignment operator. |
| 752 | /// |
| 753 | /// \returns *this after assignment of RHS. |
| 754 | APInt &operator=(const APInt &RHS) { |
| 755 | // If the bitwidths are the same, we can avoid mucking with memory |
| 756 | if (isSingleWord() && RHS.isSingleWord()) { |
| 757 | U.VAL = RHS.U.VAL; |
| 758 | BitWidth = RHS.BitWidth; |
| 759 | return clearUnusedBits(); |
| 760 | } |
| 761 | |
| 762 | AssignSlowCase(RHS); |
| 763 | return *this; |
| 764 | } |
| 765 | |
| 766 | /// Move assignment operator. |
| 767 | APInt &operator=(APInt &&that) { |
| 768 | #ifdef EXPENSIVE_CHECKS |
| 769 | // Some std::shuffle implementations still do self-assignment. |
| 770 | if (this == &that) |
| 771 | return *this; |
| 772 | #endif |
| 773 | assert(this != &that && "Self-move not supported")((void)0); |
| 774 | if (!isSingleWord()) |
| 775 | delete[] U.pVal; |
| 776 | |
| 777 | // Use memcpy so that type based alias analysis sees both VAL and pVal |
| 778 | // as modified. |
| 779 | memcpy(&U, &that.U, sizeof(U)); |
| 780 | |
| 781 | BitWidth = that.BitWidth; |
| 782 | that.BitWidth = 0; |
| 783 | |
| 784 | return *this; |
| 785 | } |
| 786 | |
| 787 | /// Assignment operator. |
| 788 | /// |
| 789 | /// The RHS value is assigned to *this. If the significant bits in RHS exceed |
| 790 | /// the bit width, the excess bits are truncated. If the bit width is larger |
| 791 | /// than 64, the value is zero filled in the unspecified high order bits. |
| 792 | /// |
| 793 | /// \returns *this after assignment of RHS value. |
| 794 | APInt &operator=(uint64_t RHS) { |
| 795 | if (isSingleWord()) { |
| 796 | U.VAL = RHS; |
| 797 | return clearUnusedBits(); |
| 798 | } |
| 799 | U.pVal[0] = RHS; |
| 800 | memset(U.pVal + 1, 0, (getNumWords() - 1) * APINT_WORD_SIZE); |
| 801 | return *this; |
| 802 | } |
| 803 | |
| 804 | /// Bitwise AND assignment operator. |
| 805 | /// |
| 806 | /// Performs a bitwise AND operation on this APInt and RHS. The result is |
| 807 | /// assigned to *this. |
| 808 | /// |
| 809 | /// \returns *this after ANDing with RHS. |
| 810 | APInt &operator&=(const APInt &RHS) { |
| 811 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((void)0); |
| 812 | if (isSingleWord()) |
| 813 | U.VAL &= RHS.U.VAL; |
| 814 | else |
| 815 | AndAssignSlowCase(RHS); |
| 816 | return *this; |
| 817 | } |
| 818 | |
| 819 | /// Bitwise AND assignment operator. |
| 820 | /// |
| 821 | /// Performs a bitwise AND operation on this APInt and RHS. RHS is |
| 822 | /// logically zero-extended or truncated to match the bit-width of |
| 823 | /// the LHS. |
| 824 | APInt &operator&=(uint64_t RHS) { |
| 825 | if (isSingleWord()) { |
| 826 | U.VAL &= RHS; |
| 827 | return *this; |
| 828 | } |
| 829 | U.pVal[0] &= RHS; |
| 830 | memset(U.pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE); |
| 831 | return *this; |
| 832 | } |
| 833 | |
| 834 | /// Bitwise OR assignment operator. |
| 835 | /// |
| 836 | /// Performs a bitwise OR operation on this APInt and RHS. The result is |
| 837 | /// assigned *this; |
| 838 | /// |
| 839 | /// \returns *this after ORing with RHS. |
| 840 | APInt &operator|=(const APInt &RHS) { |
| 841 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((void)0); |
| 842 | if (isSingleWord()) |
| 843 | U.VAL |= RHS.U.VAL; |
| 844 | else |
| 845 | OrAssignSlowCase(RHS); |
| 846 | return *this; |
| 847 | } |
| 848 | |
| 849 | /// Bitwise OR assignment operator. |
| 850 | /// |
| 851 | /// Performs a bitwise OR operation on this APInt and RHS. RHS is |
| 852 | /// logically zero-extended or truncated to match the bit-width of |
| 853 | /// the LHS. |
| 854 | APInt &operator|=(uint64_t RHS) { |
| 855 | if (isSingleWord()) { |
| 856 | U.VAL |= RHS; |
| 857 | return clearUnusedBits(); |
| 858 | } |
| 859 | U.pVal[0] |= RHS; |
| 860 | return *this; |
| 861 | } |
| 862 | |
| 863 | /// Bitwise XOR assignment operator. |
| 864 | /// |
| 865 | /// Performs a bitwise XOR operation on this APInt and RHS. The result is |
| 866 | /// assigned to *this. |
| 867 | /// |
| 868 | /// \returns *this after XORing with RHS. |
| 869 | APInt &operator^=(const APInt &RHS) { |
| 870 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((void)0); |
| 871 | if (isSingleWord()) |
| 872 | U.VAL ^= RHS.U.VAL; |
| 873 | else |
| 874 | XorAssignSlowCase(RHS); |
| 875 | return *this; |
| 876 | } |
| 877 | |
| 878 | /// Bitwise XOR assignment operator. |
| 879 | /// |
| 880 | /// Performs a bitwise XOR operation on this APInt and RHS. RHS is |
| 881 | /// logically zero-extended or truncated to match the bit-width of |
| 882 | /// the LHS. |
| 883 | APInt &operator^=(uint64_t RHS) { |
| 884 | if (isSingleWord()) { |
| 885 | U.VAL ^= RHS; |
| 886 | return clearUnusedBits(); |
| 887 | } |
| 888 | U.pVal[0] ^= RHS; |
| 889 | return *this; |
| 890 | } |
| 891 | |
| 892 | /// Multiplication assignment operator. |
| 893 | /// |
| 894 | /// Multiplies this APInt by RHS and assigns the result to *this. |
| 895 | /// |
| 896 | /// \returns *this |
| 897 | APInt &operator*=(const APInt &RHS); |
| 898 | APInt &operator*=(uint64_t RHS); |
| 899 | |
| 900 | /// Addition assignment operator. |
| 901 | /// |
| 902 | /// Adds RHS to *this and assigns the result to *this. |
| 903 | /// |
| 904 | /// \returns *this |
| 905 | APInt &operator+=(const APInt &RHS); |
| 906 | APInt &operator+=(uint64_t RHS); |
| 907 | |
| 908 | /// Subtraction assignment operator. |
| 909 | /// |
| 910 | /// Subtracts RHS from *this and assigns the result to *this. |
| 911 | /// |
| 912 | /// \returns *this |
| 913 | APInt &operator-=(const APInt &RHS); |
| 914 | APInt &operator-=(uint64_t RHS); |
| 915 | |
| 916 | /// Left-shift assignment function. |
| 917 | /// |
| 918 | /// Shifts *this left by shiftAmt and assigns the result to *this. |
| 919 | /// |
| 920 | /// \returns *this after shifting left by ShiftAmt |
| 921 | APInt &operator<<=(unsigned ShiftAmt) { |
| 922 | assert(ShiftAmt <= BitWidth && "Invalid shift amount")((void)0); |
| 923 | if (isSingleWord()) { |
| 924 | if (ShiftAmt == BitWidth) |
| 925 | U.VAL = 0; |
| 926 | else |
| 927 | U.VAL <<= ShiftAmt; |
| 928 | return clearUnusedBits(); |
| 929 | } |
| 930 | shlSlowCase(ShiftAmt); |
| 931 | return *this; |
| 932 | } |
| 933 | |
| 934 | /// Left-shift assignment function. |
| 935 | /// |
| 936 | /// Shifts *this left by shiftAmt and assigns the result to *this. |
| 937 | /// |
| 938 | /// \returns *this after shifting left by ShiftAmt |
| 939 | APInt &operator<<=(const APInt &ShiftAmt); |
| 940 | |
| 941 | /// @} |
| 942 | /// \name Binary Operators |
| 943 | /// @{ |
| 944 | |
| 945 | /// Multiplication operator. |
| 946 | /// |
| 947 | /// Multiplies this APInt by RHS and returns the result. |
| 948 | APInt operator*(const APInt &RHS) const; |
| 949 | |
| 950 | /// Left logical shift operator. |
| 951 | /// |
| 952 | /// Shifts this APInt left by \p Bits and returns the result. |
| 953 | APInt operator<<(unsigned Bits) const { return shl(Bits); } |
| 954 | |
| 955 | /// Left logical shift operator. |
| 956 | /// |
| 957 | /// Shifts this APInt left by \p Bits and returns the result. |
| 958 | APInt operator<<(const APInt &Bits) const { return shl(Bits); } |
| 959 | |
| 960 | /// Arithmetic right-shift function. |
| 961 | /// |
| 962 | /// Arithmetic right-shift this APInt by shiftAmt. |
| 963 | APInt ashr(unsigned ShiftAmt) const { |
| 964 | APInt R(*this); |
| 965 | R.ashrInPlace(ShiftAmt); |
| 966 | return R; |
| 967 | } |
| 968 | |
| 969 | /// Arithmetic right-shift this APInt by ShiftAmt in place. |
| 970 | void ashrInPlace(unsigned ShiftAmt) { |
| 971 | assert(ShiftAmt <= BitWidth && "Invalid shift amount")((void)0); |
| 972 | if (isSingleWord()) { |
| 973 | int64_t SExtVAL = SignExtend64(U.VAL, BitWidth); |
| 974 | if (ShiftAmt == BitWidth) |
| 975 | U.VAL = SExtVAL >> (APINT_BITS_PER_WORD - 1); // Fill with sign bit. |
| 976 | else |
| 977 | U.VAL = SExtVAL >> ShiftAmt; |
| 978 | clearUnusedBits(); |
| 979 | return; |
| 980 | } |
| 981 | ashrSlowCase(ShiftAmt); |
| 982 | } |
| 983 | |
| 984 | /// Logical right-shift function. |
| 985 | /// |
| 986 | /// Logical right-shift this APInt by shiftAmt. |
| 987 | APInt lshr(unsigned shiftAmt) const { |
| 988 | APInt R(*this); |
| 989 | R.lshrInPlace(shiftAmt); |
| 990 | return R; |
| 991 | } |
| 992 | |
| 993 | /// Logical right-shift this APInt by ShiftAmt in place. |
| 994 | void lshrInPlace(unsigned ShiftAmt) { |
| 995 | assert(ShiftAmt <= BitWidth && "Invalid shift amount")((void)0); |
| 996 | if (isSingleWord()) { |
| 997 | if (ShiftAmt == BitWidth) |
| 998 | U.VAL = 0; |
| 999 | else |
| 1000 | U.VAL >>= ShiftAmt; |
| 1001 | return; |
| 1002 | } |
| 1003 | lshrSlowCase(ShiftAmt); |
| 1004 | } |
| 1005 | |
| 1006 | /// Left-shift function. |
| 1007 | /// |
| 1008 | /// Left-shift this APInt by shiftAmt. |
| 1009 | APInt shl(unsigned shiftAmt) const { |
| 1010 | APInt R(*this); |
| 1011 | R <<= shiftAmt; |
| 1012 | return R; |
| 1013 | } |
| 1014 | |
| 1015 | /// Rotate left by rotateAmt. |
| 1016 | APInt rotl(unsigned rotateAmt) const; |
| 1017 | |
| 1018 | /// Rotate right by rotateAmt. |
| 1019 | APInt rotr(unsigned rotateAmt) const; |
| 1020 | |
| 1021 | /// Arithmetic right-shift function. |
| 1022 | /// |
| 1023 | /// Arithmetic right-shift this APInt by shiftAmt. |
| 1024 | APInt ashr(const APInt &ShiftAmt) const { |
| 1025 | APInt R(*this); |
| 1026 | R.ashrInPlace(ShiftAmt); |
| 1027 | return R; |
| 1028 | } |
| 1029 | |
| 1030 | /// Arithmetic right-shift this APInt by shiftAmt in place. |
| 1031 | void ashrInPlace(const APInt &shiftAmt); |
| 1032 | |
| 1033 | /// Logical right-shift function. |
| 1034 | /// |
| 1035 | /// Logical right-shift this APInt by shiftAmt. |
| 1036 | APInt lshr(const APInt &ShiftAmt) const { |
| 1037 | APInt R(*this); |
| 1038 | R.lshrInPlace(ShiftAmt); |
| 1039 | return R; |
| 1040 | } |
| 1041 | |
| 1042 | /// Logical right-shift this APInt by ShiftAmt in place. |
| 1043 | void lshrInPlace(const APInt &ShiftAmt); |
| 1044 | |
| 1045 | /// Left-shift function. |
| 1046 | /// |
| 1047 | /// Left-shift this APInt by shiftAmt. |
| 1048 | APInt shl(const APInt &ShiftAmt) const { |
| 1049 | APInt R(*this); |
| 1050 | R <<= ShiftAmt; |
| 1051 | return R; |
| 1052 | } |
| 1053 | |
| 1054 | /// Rotate left by rotateAmt. |
| 1055 | APInt rotl(const APInt &rotateAmt) const; |
| 1056 | |
| 1057 | /// Rotate right by rotateAmt. |
| 1058 | APInt rotr(const APInt &rotateAmt) const; |
| 1059 | |
| 1060 | /// Unsigned division operation. |
| 1061 | /// |
| 1062 | /// Perform an unsigned divide operation on this APInt by RHS. Both this and |
| 1063 | /// RHS are treated as unsigned quantities for purposes of this division. |
| 1064 | /// |
| 1065 | /// \returns a new APInt value containing the division result, rounded towards |
| 1066 | /// zero. |
| 1067 | APInt udiv(const APInt &RHS) const; |
| 1068 | APInt udiv(uint64_t RHS) const; |
| 1069 | |
| 1070 | /// Signed division function for APInt. |
| 1071 | /// |
| 1072 | /// Signed divide this APInt by APInt RHS. |
| 1073 | /// |
| 1074 | /// The result is rounded towards zero. |
| 1075 | APInt sdiv(const APInt &RHS) const; |
| 1076 | APInt sdiv(int64_t RHS) const; |
| 1077 | |
| 1078 | /// Unsigned remainder operation. |
| 1079 | /// |
| 1080 | /// Perform an unsigned remainder operation on this APInt with RHS being the |
| 1081 | /// divisor. Both this and RHS are treated as unsigned quantities for purposes |
| 1082 | /// of this operation. Note that this is a true remainder operation and not a |
| 1083 | /// modulo operation because the sign follows the sign of the dividend which |
| 1084 | /// is *this. |
| 1085 | /// |
| 1086 | /// \returns a new APInt value containing the remainder result |
| 1087 | APInt urem(const APInt &RHS) const; |
| 1088 | uint64_t urem(uint64_t RHS) const; |
| 1089 | |
| 1090 | /// Function for signed remainder operation. |
| 1091 | /// |
| 1092 | /// Signed remainder operation on APInt. |
| 1093 | APInt srem(const APInt &RHS) const; |
| 1094 | int64_t srem(int64_t RHS) const; |
| 1095 | |
| 1096 | /// Dual division/remainder interface. |
| 1097 | /// |
| 1098 | /// Sometimes it is convenient to divide two APInt values and obtain both the |
| 1099 | /// quotient and remainder. This function does both operations in the same |
| 1100 | /// computation making it a little more efficient. The pair of input arguments |
| 1101 | /// may overlap with the pair of output arguments. It is safe to call |
| 1102 | /// udivrem(X, Y, X, Y), for example. |
| 1103 | static void udivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient, |
| 1104 | APInt &Remainder); |
| 1105 | static void udivrem(const APInt &LHS, uint64_t RHS, APInt &Quotient, |
| 1106 | uint64_t &Remainder); |
| 1107 | |
| 1108 | static void sdivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient, |
| 1109 | APInt &Remainder); |
| 1110 | static void sdivrem(const APInt &LHS, int64_t RHS, APInt &Quotient, |
| 1111 | int64_t &Remainder); |
| 1112 | |
| 1113 | // Operations that return overflow indicators. |
| 1114 | APInt sadd_ov(const APInt &RHS, bool &Overflow) const; |
| 1115 | APInt uadd_ov(const APInt &RHS, bool &Overflow) const; |
| 1116 | APInt ssub_ov(const APInt &RHS, bool &Overflow) const; |
| 1117 | APInt usub_ov(const APInt &RHS, bool &Overflow) const; |
| 1118 | APInt sdiv_ov(const APInt &RHS, bool &Overflow) const; |
| 1119 | APInt smul_ov(const APInt &RHS, bool &Overflow) const; |
| 1120 | APInt umul_ov(const APInt &RHS, bool &Overflow) const; |
| 1121 | APInt sshl_ov(const APInt &Amt, bool &Overflow) const; |
| 1122 | APInt ushl_ov(const APInt &Amt, bool &Overflow) const; |
| 1123 | |
| 1124 | // Operations that saturate |
| 1125 | APInt sadd_sat(const APInt &RHS) const; |
| 1126 | APInt uadd_sat(const APInt &RHS) const; |
| 1127 | APInt ssub_sat(const APInt &RHS) const; |
| 1128 | APInt usub_sat(const APInt &RHS) const; |
| 1129 | APInt smul_sat(const APInt &RHS) const; |
| 1130 | APInt umul_sat(const APInt &RHS) const; |
| 1131 | APInt sshl_sat(const APInt &RHS) const; |
| 1132 | APInt ushl_sat(const APInt &RHS) const; |
| 1133 | |
| 1134 | /// Array-indexing support. |
| 1135 | /// |
| 1136 | /// \returns the bit value at bitPosition |
| 1137 | bool operator[](unsigned bitPosition) const { |
| 1138 | assert(bitPosition < getBitWidth() && "Bit position out of bounds!")((void)0); |
| 1139 | return (maskBit(bitPosition) & getWord(bitPosition)) != 0; |
| 1140 | } |
| 1141 | |
| 1142 | /// @} |
| 1143 | /// \name Comparison Operators |
| 1144 | /// @{ |
| 1145 | |
| 1146 | /// Equality operator. |
| 1147 | /// |
| 1148 | /// Compares this APInt with RHS for the validity of the equality |
| 1149 | /// relationship. |
| 1150 | bool operator==(const APInt &RHS) const { |
| 1151 | assert(BitWidth == RHS.BitWidth && "Comparison requires equal bit widths")((void)0); |
| 1152 | if (isSingleWord()) |
| 1153 | return U.VAL == RHS.U.VAL; |
| 1154 | return EqualSlowCase(RHS); |
| 1155 | } |
| 1156 | |
| 1157 | /// Equality operator. |
| 1158 | /// |
| 1159 | /// Compares this APInt with a uint64_t for the validity of the equality |
| 1160 | /// relationship. |
| 1161 | /// |
| 1162 | /// \returns true if *this == Val |
| 1163 | bool operator==(uint64_t Val) const { |
| 1164 | return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() == Val; |
| 1165 | } |
| 1166 | |
| 1167 | /// Equality comparison. |
| 1168 | /// |
| 1169 | /// Compares this APInt with RHS for the validity of the equality |
| 1170 | /// relationship. |
| 1171 | /// |
| 1172 | /// \returns true if *this == Val |
| 1173 | bool eq(const APInt &RHS) const { return (*this) == RHS; } |
| 1174 | |
| 1175 | /// Inequality operator. |
| 1176 | /// |
| 1177 | /// Compares this APInt with RHS for the validity of the inequality |
| 1178 | /// relationship. |
| 1179 | /// |
| 1180 | /// \returns true if *this != Val |
| 1181 | bool operator!=(const APInt &RHS) const { return !((*this) == RHS); } |
| 1182 | |
| 1183 | /// Inequality operator. |
| 1184 | /// |
| 1185 | /// Compares this APInt with a uint64_t for the validity of the inequality |
| 1186 | /// relationship. |
| 1187 | /// |
| 1188 | /// \returns true if *this != Val |
| 1189 | bool operator!=(uint64_t Val) const { return !((*this) == Val); } |
| 1190 | |
| 1191 | /// Inequality comparison |
| 1192 | /// |
| 1193 | /// Compares this APInt with RHS for the validity of the inequality |
| 1194 | /// relationship. |
| 1195 | /// |
| 1196 | /// \returns true if *this != Val |
| 1197 | bool ne(const APInt &RHS) const { return !((*this) == RHS); } |
| 1198 | |
| 1199 | /// Unsigned less than comparison |
| 1200 | /// |
| 1201 | /// Regards both *this and RHS as unsigned quantities and compares them for |
| 1202 | /// the validity of the less-than relationship. |
| 1203 | /// |
| 1204 | /// \returns true if *this < RHS when both are considered unsigned. |
| 1205 | bool ult(const APInt &RHS) const { return compare(RHS) < 0; } |
| 1206 | |
| 1207 | /// Unsigned less than comparison |
| 1208 | /// |
| 1209 | /// Regards both *this as an unsigned quantity and compares it with RHS for |
| 1210 | /// the validity of the less-than relationship. |
| 1211 | /// |
| 1212 | /// \returns true if *this < RHS when considered unsigned. |
| 1213 | bool ult(uint64_t RHS) const { |
| 1214 | // Only need to check active bits if not a single word. |
| 1215 | return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() < RHS; |
| 1216 | } |
| 1217 | |
| 1218 | /// Signed less than comparison |
| 1219 | /// |
| 1220 | /// Regards both *this and RHS as signed quantities and compares them for |
| 1221 | /// validity of the less-than relationship. |
| 1222 | /// |
| 1223 | /// \returns true if *this < RHS when both are considered signed. |
| 1224 | bool slt(const APInt &RHS) const { return compareSigned(RHS) < 0; } |
| 1225 | |
| 1226 | /// Signed less than comparison |
| 1227 | /// |
| 1228 | /// Regards both *this as a signed quantity and compares it with RHS for |
| 1229 | /// the validity of the less-than relationship. |
| 1230 | /// |
| 1231 | /// \returns true if *this < RHS when considered signed. |
| 1232 | bool slt(int64_t RHS) const { |
| 1233 | return (!isSingleWord() && getMinSignedBits() > 64) ? isNegative() |
| 1234 | : getSExtValue() < RHS; |
| 1235 | } |
| 1236 | |
| 1237 | /// Unsigned less or equal comparison |
| 1238 | /// |
| 1239 | /// Regards both *this and RHS as unsigned quantities and compares them for |
| 1240 | /// validity of the less-or-equal relationship. |
| 1241 | /// |
| 1242 | /// \returns true if *this <= RHS when both are considered unsigned. |
| 1243 | bool ule(const APInt &RHS) const { return compare(RHS) <= 0; } |
| 1244 | |
| 1245 | /// Unsigned less or equal comparison |
| 1246 | /// |
| 1247 | /// Regards both *this as an unsigned quantity and compares it with RHS for |
| 1248 | /// the validity of the less-or-equal relationship. |
| 1249 | /// |
| 1250 | /// \returns true if *this <= RHS when considered unsigned. |
| 1251 | bool ule(uint64_t RHS) const { return !ugt(RHS); } |
| 1252 | |
| 1253 | /// Signed less or equal comparison |
| 1254 | /// |
| 1255 | /// Regards both *this and RHS as signed quantities and compares them for |
| 1256 | /// validity of the less-or-equal relationship. |
| 1257 | /// |
| 1258 | /// \returns true if *this <= RHS when both are considered signed. |
| 1259 | bool sle(const APInt &RHS) const { return compareSigned(RHS) <= 0; } |
| 1260 | |
| 1261 | /// Signed less or equal comparison |
| 1262 | /// |
| 1263 | /// Regards both *this as a signed quantity and compares it with RHS for the |
| 1264 | /// validity of the less-or-equal relationship. |
| 1265 | /// |
| 1266 | /// \returns true if *this <= RHS when considered signed. |
| 1267 | bool sle(uint64_t RHS) const { return !sgt(RHS); } |
| 1268 | |
| 1269 | /// Unsigned greater than comparison |
| 1270 | /// |
| 1271 | /// Regards both *this and RHS as unsigned quantities and compares them for |
| 1272 | /// the validity of the greater-than relationship. |
| 1273 | /// |
| 1274 | /// \returns true if *this > RHS when both are considered unsigned. |
| 1275 | bool ugt(const APInt &RHS) const { return !ule(RHS); } |
| 1276 | |
| 1277 | /// Unsigned greater than comparison |
| 1278 | /// |
| 1279 | /// Regards both *this as an unsigned quantity and compares it with RHS for |
| 1280 | /// the validity of the greater-than relationship. |
| 1281 | /// |
| 1282 | /// \returns true if *this > RHS when considered unsigned. |
| 1283 | bool ugt(uint64_t RHS) const { |
| 1284 | // Only need to check active bits if not a single word. |
| 1285 | return (!isSingleWord() && getActiveBits() > 64) || getZExtValue() > RHS; |
| 1286 | } |
| 1287 | |
| 1288 | /// Signed greater than comparison |
| 1289 | /// |
| 1290 | /// Regards both *this and RHS as signed quantities and compares them for the |
| 1291 | /// validity of the greater-than relationship. |
| 1292 | /// |
| 1293 | /// \returns true if *this > RHS when both are considered signed. |
| 1294 | bool sgt(const APInt &RHS) const { return !sle(RHS); } |
| 1295 | |
| 1296 | /// Signed greater than comparison |
| 1297 | /// |
| 1298 | /// Regards both *this as a signed quantity and compares it with RHS for |
| 1299 | /// the validity of the greater-than relationship. |
| 1300 | /// |
| 1301 | /// \returns true if *this > RHS when considered signed. |
| 1302 | bool sgt(int64_t RHS) const { |
| 1303 | return (!isSingleWord() && getMinSignedBits() > 64) ? !isNegative() |
| 1304 | : getSExtValue() > RHS; |
| 1305 | } |
| 1306 | |
| 1307 | /// Unsigned greater or equal comparison |
| 1308 | /// |
| 1309 | /// Regards both *this and RHS as unsigned quantities and compares them for |
| 1310 | /// validity of the greater-or-equal relationship. |
| 1311 | /// |
| 1312 | /// \returns true if *this >= RHS when both are considered unsigned. |
| 1313 | bool uge(const APInt &RHS) const { return !ult(RHS); } |
| 1314 | |
| 1315 | /// Unsigned greater or equal comparison |
| 1316 | /// |
| 1317 | /// Regards both *this as an unsigned quantity and compares it with RHS for |
| 1318 | /// the validity of the greater-or-equal relationship. |
| 1319 | /// |
| 1320 | /// \returns true if *this >= RHS when considered unsigned. |
| 1321 | bool uge(uint64_t RHS) const { return !ult(RHS); } |
| 1322 | |
| 1323 | /// Signed greater or equal comparison |
| 1324 | /// |
| 1325 | /// Regards both *this and RHS as signed quantities and compares them for |
| 1326 | /// validity of the greater-or-equal relationship. |
| 1327 | /// |
| 1328 | /// \returns true if *this >= RHS when both are considered signed. |
| 1329 | bool sge(const APInt &RHS) const { return !slt(RHS); } |
| 1330 | |
| 1331 | /// Signed greater or equal comparison |
| 1332 | /// |
| 1333 | /// Regards both *this as a signed quantity and compares it with RHS for |
| 1334 | /// the validity of the greater-or-equal relationship. |
| 1335 | /// |
| 1336 | /// \returns true if *this >= RHS when considered signed. |
| 1337 | bool sge(int64_t RHS) const { return !slt(RHS); } |
| 1338 | |
| 1339 | /// This operation tests if there are any pairs of corresponding bits |
| 1340 | /// between this APInt and RHS that are both set. |
| 1341 | bool intersects(const APInt &RHS) const { |
| 1342 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((void)0); |
| 1343 | if (isSingleWord()) |
| 1344 | return (U.VAL & RHS.U.VAL) != 0; |
| 1345 | return intersectsSlowCase(RHS); |
| 1346 | } |
| 1347 | |
| 1348 | /// This operation checks that all bits set in this APInt are also set in RHS. |
| 1349 | bool isSubsetOf(const APInt &RHS) const { |
| 1350 | assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((void)0); |
| 1351 | if (isSingleWord()) |
| 1352 | return (U.VAL & ~RHS.U.VAL) == 0; |
| 1353 | return isSubsetOfSlowCase(RHS); |
| 1354 | } |
| 1355 | |
| 1356 | /// @} |
| 1357 | /// \name Resizing Operators |
| 1358 | /// @{ |
| 1359 | |
| 1360 | /// Truncate to new width. |
| 1361 | /// |
| 1362 | /// Truncate the APInt to a specified width. It is an error to specify a width |
| 1363 | /// that is greater than or equal to the current width. |
| 1364 | APInt trunc(unsigned width) const; |
| 1365 | |
| 1366 | /// Truncate to new width with unsigned saturation. |
| 1367 | /// |
| 1368 | /// If the APInt, treated as unsigned integer, can be losslessly truncated to |
| 1369 | /// the new bitwidth, then return truncated APInt. Else, return max value. |
| 1370 | APInt truncUSat(unsigned width) const; |
| 1371 | |
| 1372 | /// Truncate to new width with signed saturation. |
| 1373 | /// |
| 1374 | /// If this APInt, treated as signed integer, can be losslessly truncated to |
| 1375 | /// the new bitwidth, then return truncated APInt. Else, return either |
| 1376 | /// signed min value if the APInt was negative, or signed max value. |
| 1377 | APInt truncSSat(unsigned width) const; |
| 1378 | |
| 1379 | /// Sign extend to a new width. |
| 1380 | /// |
| 1381 | /// This operation sign extends the APInt to a new width. If the high order |
| 1382 | /// bit is set, the fill on the left will be done with 1 bits, otherwise zero. |
| 1383 | /// It is an error to specify a width that is less than or equal to the |
| 1384 | /// current width. |
| 1385 | APInt sext(unsigned width) const; |
| 1386 | |
| 1387 | /// Zero extend to a new width. |
| 1388 | /// |
| 1389 | /// This operation zero extends the APInt to a new width. The high order bits |
| 1390 | /// are filled with 0 bits. It is an error to specify a width that is less |
| 1391 | /// than or equal to the current width. |
| 1392 | APInt zext(unsigned width) const; |
| 1393 | |
| 1394 | /// Sign extend or truncate to width |
| 1395 | /// |
| 1396 | /// Make this APInt have the bit width given by \p width. The value is sign |
| 1397 | /// extended, truncated, or left alone to make it that width. |
| 1398 | APInt sextOrTrunc(unsigned width) const; |
| 1399 | |
| 1400 | /// Zero extend or truncate to width |
| 1401 | /// |
| 1402 | /// Make this APInt have the bit width given by \p width. The value is zero |
| 1403 | /// extended, truncated, or left alone to make it that width. |
| 1404 | APInt zextOrTrunc(unsigned width) const; |
| 1405 | |
| 1406 | /// Truncate to width |
| 1407 | /// |
| 1408 | /// Make this APInt have the bit width given by \p width. The value is |
| 1409 | /// truncated or left alone to make it that width. |
| 1410 | APInt truncOrSelf(unsigned width) const; |
| 1411 | |
| 1412 | /// Sign extend or truncate to width |
| 1413 | /// |
| 1414 | /// Make this APInt have the bit width given by \p width. The value is sign |
| 1415 | /// extended, or left alone to make it that width. |
| 1416 | APInt sextOrSelf(unsigned width) const; |
| 1417 | |
| 1418 | /// Zero extend or truncate to width |
| 1419 | /// |
| 1420 | /// Make this APInt have the bit width given by \p width. The value is zero |
| 1421 | /// extended, or left alone to make it that width. |
| 1422 | APInt zextOrSelf(unsigned width) const; |
| 1423 | |
| 1424 | /// @} |
| 1425 | /// \name Bit Manipulation Operators |
| 1426 | /// @{ |
| 1427 | |
| 1428 | /// Set every bit to 1. |
| 1429 | void setAllBits() { |
| 1430 | if (isSingleWord()) |
| 1431 | U.VAL = WORDTYPE_MAX; |
| 1432 | else |
| 1433 | // Set all the bits in all the words. |
| 1434 | memset(U.pVal, -1, getNumWords() * APINT_WORD_SIZE); |
| 1435 | // Clear the unused ones |
| 1436 | clearUnusedBits(); |
| 1437 | } |
| 1438 | |
| 1439 | /// Set a given bit to 1. |
| 1440 | /// |
| 1441 | /// Set the given bit to 1 whose position is given as "bitPosition". |
| 1442 | void setBit(unsigned BitPosition) { |
| 1443 | assert(BitPosition < BitWidth && "BitPosition out of range")((void)0); |
| 1444 | WordType Mask = maskBit(BitPosition); |
| 1445 | if (isSingleWord()) |
| 1446 | U.VAL |= Mask; |
| 1447 | else |
| 1448 | U.pVal[whichWord(BitPosition)] |= Mask; |
| 1449 | } |
| 1450 | |
| 1451 | /// Set the sign bit to 1. |
| 1452 | void setSignBit() { |
| 1453 | setBit(BitWidth - 1); |
| 1454 | } |
| 1455 | |
| 1456 | /// Set a given bit to a given value. |
| 1457 | void setBitVal(unsigned BitPosition, bool BitValue) { |
| 1458 | if (BitValue) |
| 1459 | setBit(BitPosition); |
| 1460 | else |
| 1461 | clearBit(BitPosition); |
| 1462 | } |
| 1463 | |
| 1464 | /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1. |
| 1465 | /// This function handles "wrap" case when \p loBit >= \p hiBit, and calls |
| 1466 | /// setBits when \p loBit < \p hiBit. |
| 1467 | /// For \p loBit == \p hiBit wrap case, set every bit to 1. |
| 1468 | void setBitsWithWrap(unsigned loBit, unsigned hiBit) { |
| 1469 | assert(hiBit <= BitWidth && "hiBit out of range")((void)0); |
| 1470 | assert(loBit <= BitWidth && "loBit out of range")((void)0); |
| 1471 | if (loBit < hiBit) { |
| 1472 | setBits(loBit, hiBit); |
| 1473 | return; |
| 1474 | } |
| 1475 | setLowBits(hiBit); |
| 1476 | setHighBits(BitWidth - loBit); |
| 1477 | } |
| 1478 | |
| 1479 | /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1. |
| 1480 | /// This function handles case when \p loBit <= \p hiBit. |
| 1481 | void setBits(unsigned loBit, unsigned hiBit) { |
| 1482 | assert(hiBit <= BitWidth && "hiBit out of range")((void)0); |
| 1483 | assert(loBit <= BitWidth && "loBit out of range")((void)0); |
| 1484 | assert(loBit <= hiBit && "loBit greater than hiBit")((void)0); |
| 1485 | if (loBit == hiBit) |
| 1486 | return; |
| 1487 | if (loBit < APINT_BITS_PER_WORD && hiBit <= APINT_BITS_PER_WORD) { |
| 1488 | uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - (hiBit - loBit)); |
| 1489 | mask <<= loBit; |
| 1490 | if (isSingleWord()) |
| 1491 | U.VAL |= mask; |
| 1492 | else |
| 1493 | U.pVal[0] |= mask; |
| 1494 | } else { |
| 1495 | setBitsSlowCase(loBit, hiBit); |
| 1496 | } |
| 1497 | } |
| 1498 | |
| 1499 | /// Set the top bits starting from loBit. |
| 1500 | void setBitsFrom(unsigned loBit) { |
| 1501 | return setBits(loBit, BitWidth); |
| 1502 | } |
| 1503 | |
| 1504 | /// Set the bottom loBits bits. |
| 1505 | void setLowBits(unsigned loBits) { |
| 1506 | return setBits(0, loBits); |
| 1507 | } |
| 1508 | |
| 1509 | /// Set the top hiBits bits. |
| 1510 | void setHighBits(unsigned hiBits) { |
| 1511 | return setBits(BitWidth - hiBits, BitWidth); |
| 1512 | } |
| 1513 | |
| 1514 | /// Set every bit to 0. |
| 1515 | void clearAllBits() { |
| 1516 | if (isSingleWord()) |
| 1517 | U.VAL = 0; |
| 1518 | else |
| 1519 | memset(U.pVal, 0, getNumWords() * APINT_WORD_SIZE); |
| 1520 | } |
| 1521 | |
| 1522 | /// Set a given bit to 0. |
| 1523 | /// |
| 1524 | /// Set the given bit to 0 whose position is given as "bitPosition". |
| 1525 | void clearBit(unsigned BitPosition) { |
| 1526 | assert(BitPosition < BitWidth && "BitPosition out of range")((void)0); |
| 1527 | WordType Mask = ~maskBit(BitPosition); |
| 1528 | if (isSingleWord()) |
| 1529 | U.VAL &= Mask; |
| 1530 | else |
| 1531 | U.pVal[whichWord(BitPosition)] &= Mask; |
| 1532 | } |
| 1533 | |
| 1534 | /// Set bottom loBits bits to 0. |
| 1535 | void clearLowBits(unsigned loBits) { |
| 1536 | assert(loBits <= BitWidth && "More bits than bitwidth")((void)0); |
| 1537 | APInt Keep = getHighBitsSet(BitWidth, BitWidth - loBits); |
| 1538 | *this &= Keep; |
| 1539 | } |
| 1540 | |
| 1541 | /// Set the sign bit to 0. |
| 1542 | void clearSignBit() { |
| 1543 | clearBit(BitWidth - 1); |
| 1544 | } |
| 1545 | |
| 1546 | /// Toggle every bit to its opposite value. |
| 1547 | void flipAllBits() { |
| 1548 | if (isSingleWord()) { |
| 1549 | U.VAL ^= WORDTYPE_MAX; |
| 1550 | clearUnusedBits(); |
| 1551 | } else { |
| 1552 | flipAllBitsSlowCase(); |
| 1553 | } |
| 1554 | } |
| 1555 | |
| 1556 | /// Toggles a given bit to its opposite value. |
| 1557 | /// |
| 1558 | /// Toggle a given bit to its opposite value whose position is given |
| 1559 | /// as "bitPosition". |
| 1560 | void flipBit(unsigned bitPosition); |
| 1561 | |
| 1562 | /// Negate this APInt in place. |
| 1563 | void negate() { |
| 1564 | flipAllBits(); |
| 1565 | ++(*this); |
| 1566 | } |
| 1567 | |
| 1568 | /// Insert the bits from a smaller APInt starting at bitPosition. |
| 1569 | void insertBits(const APInt &SubBits, unsigned bitPosition); |
| 1570 | void insertBits(uint64_t SubBits, unsigned bitPosition, unsigned numBits); |
| 1571 | |
| 1572 | /// Return an APInt with the extracted bits [bitPosition,bitPosition+numBits). |
| 1573 | APInt extractBits(unsigned numBits, unsigned bitPosition) const; |
| 1574 | uint64_t extractBitsAsZExtValue(unsigned numBits, unsigned bitPosition) const; |
| 1575 | |
| 1576 | /// @} |
| 1577 | /// \name Value Characterization Functions |
| 1578 | /// @{ |
| 1579 | |
| 1580 | /// Return the number of bits in the APInt. |
| 1581 | unsigned getBitWidth() const { return BitWidth; } |
| 1582 | |
| 1583 | /// Get the number of words. |
| 1584 | /// |
| 1585 | /// Here one word's bitwidth equals to that of uint64_t. |
| 1586 | /// |
| 1587 | /// \returns the number of words to hold the integer value of this APInt. |
| 1588 | unsigned getNumWords() const { return getNumWords(BitWidth); } |
| 1589 | |
| 1590 | /// Get the number of words. |
| 1591 | /// |
| 1592 | /// *NOTE* Here one word's bitwidth equals to that of uint64_t. |
| 1593 | /// |
| 1594 | /// \returns the number of words to hold the integer value with a given bit |
| 1595 | /// width. |
| 1596 | static unsigned getNumWords(unsigned BitWidth) { |
| 1597 | return ((uint64_t)BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD; |
| 1598 | } |
| 1599 | |
| 1600 | /// Compute the number of active bits in the value |
| 1601 | /// |
| 1602 | /// This function returns the number of active bits which is defined as the |
| 1603 | /// bit width minus the number of leading zeros. This is used in several |
| 1604 | /// computations to see how "wide" the value is. |
| 1605 | unsigned getActiveBits() const { return BitWidth - countLeadingZeros(); } |
| 1606 | |
| 1607 | /// Compute the number of active words in the value of this APInt. |
| 1608 | /// |
| 1609 | /// This is used in conjunction with getActiveData to extract the raw value of |
| 1610 | /// the APInt. |
| 1611 | unsigned getActiveWords() const { |
| 1612 | unsigned numActiveBits = getActiveBits(); |
| 1613 | return numActiveBits ? whichWord(numActiveBits - 1) + 1 : 1; |
| 1614 | } |
| 1615 | |
| 1616 | /// Get the minimum bit size for this signed APInt |
| 1617 | /// |
| 1618 | /// Computes the minimum bit width for this APInt while considering it to be a |
| 1619 | /// signed (and probably negative) value. If the value is not negative, this |
| 1620 | /// function returns the same value as getActiveBits()+1. Otherwise, it |
| 1621 | /// returns the smallest bit width that will retain the negative value. For |
| 1622 | /// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so |
| 1623 | /// for -1, this function will always return 1. |
| 1624 | unsigned getMinSignedBits() const { return BitWidth - getNumSignBits() + 1; } |
| 1625 | |
| 1626 | /// Get zero extended value |
| 1627 | /// |
| 1628 | /// This method attempts to return the value of this APInt as a zero extended |
| 1629 | /// uint64_t. The bitwidth must be <= 64 or the value must fit within a |
| 1630 | /// uint64_t. Otherwise an assertion will result. |
| 1631 | uint64_t getZExtValue() const { |
| 1632 | if (isSingleWord()) |
| 1633 | return U.VAL; |
| 1634 | assert(getActiveBits() <= 64 && "Too many bits for uint64_t")((void)0); |
| 1635 | return U.pVal[0]; |
| 1636 | } |
| 1637 | |
| 1638 | /// Get sign extended value |
| 1639 | /// |
| 1640 | /// This method attempts to return the value of this APInt as a sign extended |
| 1641 | /// int64_t. The bit width must be <= 64 or the value must fit within an |
| 1642 | /// int64_t. Otherwise an assertion will result. |
| 1643 | int64_t getSExtValue() const { |
| 1644 | if (isSingleWord()) |
| 1645 | return SignExtend64(U.VAL, BitWidth); |
| 1646 | assert(getMinSignedBits() <= 64 && "Too many bits for int64_t")((void)0); |
| 1647 | return int64_t(U.pVal[0]); |
| 1648 | } |
| 1649 | |
| 1650 | /// Get bits required for string value. |
| 1651 | /// |
| 1652 | /// This method determines how many bits are required to hold the APInt |
| 1653 | /// equivalent of the string given by \p str. |
| 1654 | static unsigned getBitsNeeded(StringRef str, uint8_t radix); |
| 1655 | |
| 1656 | /// The APInt version of the countLeadingZeros functions in |
| 1657 | /// MathExtras.h. |
| 1658 | /// |
| 1659 | /// It counts the number of zeros from the most significant bit to the first |
| 1660 | /// one bit. |
| 1661 | /// |
| 1662 | /// \returns BitWidth if the value is zero, otherwise returns the number of |
| 1663 | /// zeros from the most significant bit to the first one bits. |
| 1664 | unsigned countLeadingZeros() const { |
| 1665 | if (isSingleWord()) { |
| 1666 | unsigned unusedBits = APINT_BITS_PER_WORD - BitWidth; |
| 1667 | return llvm::countLeadingZeros(U.VAL) - unusedBits; |
| 1668 | } |
| 1669 | return countLeadingZerosSlowCase(); |
| 1670 | } |
| 1671 | |
| 1672 | /// Count the number of leading one bits. |
| 1673 | /// |
| 1674 | /// This function is an APInt version of the countLeadingOnes |
| 1675 | /// functions in MathExtras.h. It counts the number of ones from the most |
| 1676 | /// significant bit to the first zero bit. |
| 1677 | /// |
| 1678 | /// \returns 0 if the high order bit is not set, otherwise returns the number |
| 1679 | /// of 1 bits from the most significant to the least |
| 1680 | unsigned countLeadingOnes() const { |
| 1681 | if (isSingleWord()) |
| 1682 | return llvm::countLeadingOnes(U.VAL << (APINT_BITS_PER_WORD - BitWidth)); |
| 1683 | return countLeadingOnesSlowCase(); |
| 1684 | } |
| 1685 | |
| 1686 | /// Computes the number of leading bits of this APInt that are equal to its |
| 1687 | /// sign bit. |
| 1688 | unsigned getNumSignBits() const { |
| 1689 | return isNegative() ? countLeadingOnes() : countLeadingZeros(); |
| 1690 | } |
| 1691 | |
| 1692 | /// Count the number of trailing zero bits. |
| 1693 | /// |
| 1694 | /// This function is an APInt version of the countTrailingZeros |
| 1695 | /// functions in MathExtras.h. It counts the number of zeros from the least |
| 1696 | /// significant bit to the first set bit. |
| 1697 | /// |
| 1698 | /// \returns BitWidth if the value is zero, otherwise returns the number of |
| 1699 | /// zeros from the least significant bit to the first one bit. |
| 1700 | unsigned countTrailingZeros() const { |
| 1701 | if (isSingleWord()) { |
| 1702 | unsigned TrailingZeros = llvm::countTrailingZeros(U.VAL); |
| 1703 | return (TrailingZeros > BitWidth ? BitWidth : TrailingZeros); |
| 1704 | } |
| 1705 | return countTrailingZerosSlowCase(); |
| 1706 | } |
| 1707 | |
| 1708 | /// Count the number of trailing one bits. |
| 1709 | /// |
| 1710 | /// This function is an APInt version of the countTrailingOnes |
| 1711 | /// functions in MathExtras.h. It counts the number of ones from the least |
| 1712 | /// significant bit to the first zero bit. |
| 1713 | /// |
| 1714 | /// \returns BitWidth if the value is all ones, otherwise returns the number |
| 1715 | /// of ones from the least significant bit to the first zero bit. |
| 1716 | unsigned countTrailingOnes() const { |
| 1717 | if (isSingleWord()) |
| 1718 | return llvm::countTrailingOnes(U.VAL); |
| 1719 | return countTrailingOnesSlowCase(); |
| 1720 | } |
| 1721 | |
| 1722 | /// Count the number of bits set. |
| 1723 | /// |
| 1724 | /// This function is an APInt version of the countPopulation functions |
| 1725 | /// in MathExtras.h. It counts the number of 1 bits in the APInt value. |
| 1726 | /// |
| 1727 | /// \returns 0 if the value is zero, otherwise returns the number of set bits. |
| 1728 | unsigned countPopulation() const { |
| 1729 | if (isSingleWord()) |
| 1730 | return llvm::countPopulation(U.VAL); |
| 1731 | return countPopulationSlowCase(); |
| 1732 | } |
| 1733 | |
| 1734 | /// @} |
| 1735 | /// \name Conversion Functions |
| 1736 | /// @{ |
| 1737 | void print(raw_ostream &OS, bool isSigned) const; |
| 1738 | |
| 1739 | /// Converts an APInt to a string and append it to Str. Str is commonly a |
| 1740 | /// SmallString. |
| 1741 | void toString(SmallVectorImpl<char> &Str, unsigned Radix, bool Signed, |
| 1742 | bool formatAsCLiteral = false) const; |
| 1743 | |
| 1744 | /// Considers the APInt to be unsigned and converts it into a string in the |
| 1745 | /// radix given. The radix can be 2, 8, 10 16, or 36. |
| 1746 | void toStringUnsigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const { |
| 1747 | toString(Str, Radix, false, false); |
| 1748 | } |
| 1749 | |
| 1750 | /// Considers the APInt to be signed and converts it into a string in the |
| 1751 | /// radix given. The radix can be 2, 8, 10, 16, or 36. |
| 1752 | void toStringSigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const { |
| 1753 | toString(Str, Radix, true, false); |
| 1754 | } |
| 1755 | |
| 1756 | /// \returns a byte-swapped representation of this APInt Value. |
| 1757 | APInt byteSwap() const; |
| 1758 | |
| 1759 | /// \returns the value with the bit representation reversed of this APInt |
| 1760 | /// Value. |
| 1761 | APInt reverseBits() const; |
| 1762 | |
| 1763 | /// Converts this APInt to a double value. |
| 1764 | double roundToDouble(bool isSigned) const; |
| 1765 | |
| 1766 | /// Converts this unsigned APInt to a double value. |
| 1767 | double roundToDouble() const { return roundToDouble(false); } |
| 1768 | |
| 1769 | /// Converts this signed APInt to a double value. |
| 1770 | double signedRoundToDouble() const { return roundToDouble(true); } |
| 1771 | |
| 1772 | /// Converts APInt bits to a double |
| 1773 | /// |
| 1774 | /// The conversion does not do a translation from integer to double, it just |
| 1775 | /// re-interprets the bits as a double. Note that it is valid to do this on |
| 1776 | /// any bit width. Exactly 64 bits will be translated. |
| 1777 | double bitsToDouble() const { |
| 1778 | return BitsToDouble(getWord(0)); |
| 1779 | } |
| 1780 | |
| 1781 | /// Converts APInt bits to a float |
| 1782 | /// |
| 1783 | /// The conversion does not do a translation from integer to float, it just |
| 1784 | /// re-interprets the bits as a float. Note that it is valid to do this on |
| 1785 | /// any bit width. Exactly 32 bits will be translated. |
| 1786 | float bitsToFloat() const { |
| 1787 | return BitsToFloat(static_cast<uint32_t>(getWord(0))); |
| 1788 | } |
| 1789 | |
| 1790 | /// Converts a double to APInt bits. |
| 1791 | /// |
| 1792 | /// The conversion does not do a translation from double to integer, it just |
| 1793 | /// re-interprets the bits of the double. |
| 1794 | static APInt doubleToBits(double V) { |
| 1795 | return APInt(sizeof(double) * CHAR_BIT8, DoubleToBits(V)); |
| 1796 | } |
| 1797 | |
| 1798 | /// Converts a float to APInt bits. |
| 1799 | /// |
| 1800 | /// The conversion does not do a translation from float to integer, it just |
| 1801 | /// re-interprets the bits of the float. |
| 1802 | static APInt floatToBits(float V) { |
| 1803 | return APInt(sizeof(float) * CHAR_BIT8, FloatToBits(V)); |
| 1804 | } |
| 1805 | |
| 1806 | /// @} |
| 1807 | /// \name Mathematics Operations |
| 1808 | /// @{ |
| 1809 | |
| 1810 | /// \returns the floor log base 2 of this APInt. |
| 1811 | unsigned logBase2() const { return getActiveBits() - 1; } |
| 1812 | |
| 1813 | /// \returns the ceil log base 2 of this APInt. |
| 1814 | unsigned ceilLogBase2() const { |
| 1815 | APInt temp(*this); |
| 1816 | --temp; |
| 1817 | return temp.getActiveBits(); |
| 1818 | } |
| 1819 | |
| 1820 | /// \returns the nearest log base 2 of this APInt. Ties round up. |
| 1821 | /// |
| 1822 | /// NOTE: When we have a BitWidth of 1, we define: |
| 1823 | /// |
| 1824 | /// log2(0) = UINT32_MAX |
| 1825 | /// log2(1) = 0 |
| 1826 | /// |
| 1827 | /// to get around any mathematical concerns resulting from |
| 1828 | /// referencing 2 in a space where 2 does no exist. |
| 1829 | unsigned nearestLogBase2() const { |
| 1830 | // Special case when we have a bitwidth of 1. If VAL is 1, then we |
| 1831 | // get 0. If VAL is 0, we get WORDTYPE_MAX which gets truncated to |
| 1832 | // UINT32_MAX. |
| 1833 | if (BitWidth == 1) |
| 1834 | return U.VAL - 1; |
| 1835 | |
| 1836 | // Handle the zero case. |
| 1837 | if (isNullValue()) |
| 1838 | return UINT32_MAX0xffffffffU; |
| 1839 | |
| 1840 | // The non-zero case is handled by computing: |
| 1841 | // |
| 1842 | // nearestLogBase2(x) = logBase2(x) + x[logBase2(x)-1]. |
| 1843 | // |
| 1844 | // where x[i] is referring to the value of the ith bit of x. |
| 1845 | unsigned lg = logBase2(); |
| 1846 | return lg + unsigned((*this)[lg - 1]); |
| 1847 | } |
| 1848 | |
| 1849 | /// \returns the log base 2 of this APInt if its an exact power of two, -1 |
| 1850 | /// otherwise |
| 1851 | int32_t exactLogBase2() const { |
| 1852 | if (!isPowerOf2()) |
| 1853 | return -1; |
| 1854 | return logBase2(); |
| 1855 | } |
| 1856 | |
| 1857 | /// Compute the square root |
| 1858 | APInt sqrt() const; |
| 1859 | |
| 1860 | /// Get the absolute value; |
| 1861 | /// |
| 1862 | /// If *this is < 0 then return -(*this), otherwise *this; |
| 1863 | APInt abs() const { |
| 1864 | if (isNegative()) |
| 1865 | return -(*this); |
| 1866 | return *this; |
| 1867 | } |
| 1868 | |
| 1869 | /// \returns the multiplicative inverse for a given modulo. |
| 1870 | APInt multiplicativeInverse(const APInt &modulo) const; |
| 1871 | |
| 1872 | /// @} |
| 1873 | /// \name Support for division by constant |
| 1874 | /// @{ |
| 1875 | |
| 1876 | /// Calculate the magic number for signed division by a constant. |
| 1877 | struct ms; |
| 1878 | ms magic() const; |
| 1879 | |
| 1880 | /// Calculate the magic number for unsigned division by a constant. |
| 1881 | struct mu; |
| 1882 | mu magicu(unsigned LeadingZeros = 0) const; |
| 1883 | |
| 1884 | /// @} |
| 1885 | /// \name Building-block Operations for APInt and APFloat |
| 1886 | /// @{ |
| 1887 | |
| 1888 | // These building block operations operate on a representation of arbitrary |
| 1889 | // precision, two's-complement, bignum integer values. They should be |
| 1890 | // sufficient to implement APInt and APFloat bignum requirements. Inputs are |
| 1891 | // generally a pointer to the base of an array of integer parts, representing |
| 1892 | // an unsigned bignum, and a count of how many parts there are. |
| 1893 | |
| 1894 | /// Sets the least significant part of a bignum to the input value, and zeroes |
| 1895 | /// out higher parts. |
| 1896 | static void tcSet(WordType *, WordType, unsigned); |
| 1897 | |
| 1898 | /// Assign one bignum to another. |
| 1899 | static void tcAssign(WordType *, const WordType *, unsigned); |
| 1900 | |
| 1901 | /// Returns true if a bignum is zero, false otherwise. |
| 1902 | static bool tcIsZero(const WordType *, unsigned); |
| 1903 | |
| 1904 | /// Extract the given bit of a bignum; returns 0 or 1. Zero-based. |
| 1905 | static int tcExtractBit(const WordType *, unsigned bit); |
| 1906 | |
| 1907 | /// Copy the bit vector of width srcBITS from SRC, starting at bit srcLSB, to |
| 1908 | /// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least |
| 1909 | /// significant bit of DST. All high bits above srcBITS in DST are |
| 1910 | /// zero-filled. |
| 1911 | static void tcExtract(WordType *, unsigned dstCount, |
| 1912 | const WordType *, unsigned srcBits, |
| 1913 | unsigned srcLSB); |
| 1914 | |
| 1915 | /// Set the given bit of a bignum. Zero-based. |
| 1916 | static void tcSetBit(WordType *, unsigned bit); |
| 1917 | |
| 1918 | /// Clear the given bit of a bignum. Zero-based. |
| 1919 | static void tcClearBit(WordType *, unsigned bit); |
| 1920 | |
| 1921 | /// Returns the bit number of the least or most significant set bit of a |
| 1922 | /// number. If the input number has no bits set -1U is returned. |
| 1923 | static unsigned tcLSB(const WordType *, unsigned n); |
| 1924 | static unsigned tcMSB(const WordType *parts, unsigned n); |
| 1925 | |
| 1926 | /// Negate a bignum in-place. |
| 1927 | static void tcNegate(WordType *, unsigned); |
| 1928 | |
| 1929 | /// DST += RHS + CARRY where CARRY is zero or one. Returns the carry flag. |
| 1930 | static WordType tcAdd(WordType *, const WordType *, |
| 1931 | WordType carry, unsigned); |
| 1932 | /// DST += RHS. Returns the carry flag. |
| 1933 | static WordType tcAddPart(WordType *, WordType, unsigned); |
| 1934 | |
| 1935 | /// DST -= RHS + CARRY where CARRY is zero or one. Returns the carry flag. |
| 1936 | static WordType tcSubtract(WordType *, const WordType *, |
| 1937 | WordType carry, unsigned); |
| 1938 | /// DST -= RHS. Returns the carry flag. |
| 1939 | static WordType tcSubtractPart(WordType *, WordType, unsigned); |
| 1940 | |
| 1941 | /// DST += SRC * MULTIPLIER + PART if add is true |
| 1942 | /// DST = SRC * MULTIPLIER + PART if add is false |
| 1943 | /// |
| 1944 | /// Requires 0 <= DSTPARTS <= SRCPARTS + 1. If DST overlaps SRC they must |
| 1945 | /// start at the same point, i.e. DST == SRC. |
| 1946 | /// |
| 1947 | /// If DSTPARTS == SRC_PARTS + 1 no overflow occurs and zero is returned. |
| 1948 | /// Otherwise DST is filled with the least significant DSTPARTS parts of the |
| 1949 | /// result, and if all of the omitted higher parts were zero return zero, |
| 1950 | /// otherwise overflow occurred and return one. |
| 1951 | static int tcMultiplyPart(WordType *dst, const WordType *src, |
| 1952 | WordType multiplier, WordType carry, |
| 1953 | unsigned srcParts, unsigned dstParts, |
| 1954 | bool add); |
| 1955 | |
| 1956 | /// DST = LHS * RHS, where DST has the same width as the operands and is |
| 1957 | /// filled with the least significant parts of the result. Returns one if |
| 1958 | /// overflow occurred, otherwise zero. DST must be disjoint from both |
| 1959 | /// operands. |
| 1960 | static int tcMultiply(WordType *, const WordType *, const WordType *, |
| 1961 | unsigned); |
| 1962 | |
| 1963 | /// DST = LHS * RHS, where DST has width the sum of the widths of the |
| 1964 | /// operands. No overflow occurs. DST must be disjoint from both operands. |
| 1965 | static void tcFullMultiply(WordType *, const WordType *, |
| 1966 | const WordType *, unsigned, unsigned); |
| 1967 | |
| 1968 | /// If RHS is zero LHS and REMAINDER are left unchanged, return one. |
| 1969 | /// Otherwise set LHS to LHS / RHS with the fractional part discarded, set |
| 1970 | /// REMAINDER to the remainder, return zero. i.e. |
| 1971 | /// |
| 1972 | /// OLD_LHS = RHS * LHS + REMAINDER |
| 1973 | /// |
| 1974 | /// SCRATCH is a bignum of the same size as the operands and result for use by |
| 1975 | /// the routine; its contents need not be initialized and are destroyed. LHS, |
| 1976 | /// REMAINDER and SCRATCH must be distinct. |
| 1977 | static int tcDivide(WordType *lhs, const WordType *rhs, |
| 1978 | WordType *remainder, WordType *scratch, |
| 1979 | unsigned parts); |
| 1980 | |
| 1981 | /// Shift a bignum left Count bits. Shifted in bits are zero. There are no |
| 1982 | /// restrictions on Count. |
| 1983 | static void tcShiftLeft(WordType *, unsigned Words, unsigned Count); |
| 1984 | |
| 1985 | /// Shift a bignum right Count bits. Shifted in bits are zero. There are no |
| 1986 | /// restrictions on Count. |
| 1987 | static void tcShiftRight(WordType *, unsigned Words, unsigned Count); |
| 1988 | |
| 1989 | /// The obvious AND, OR and XOR and complement operations. |
| 1990 | static void tcAnd(WordType *, const WordType *, unsigned); |
| 1991 | static void tcOr(WordType *, const WordType *, unsigned); |
| 1992 | static void tcXor(WordType *, const WordType *, unsigned); |
| 1993 | static void tcComplement(WordType *, unsigned); |
| 1994 | |
| 1995 | /// Comparison (unsigned) of two bignums. |
| 1996 | static int tcCompare(const WordType *, const WordType *, unsigned); |
| 1997 | |
| 1998 | /// Increment a bignum in-place. Return the carry flag. |
| 1999 | static WordType tcIncrement(WordType *dst, unsigned parts) { |
| 2000 | return tcAddPart(dst, 1, parts); |
| 2001 | } |
| 2002 | |
| 2003 | /// Decrement a bignum in-place. Return the borrow flag. |
| 2004 | static WordType tcDecrement(WordType *dst, unsigned parts) { |
| 2005 | return tcSubtractPart(dst, 1, parts); |
| 2006 | } |
| 2007 | |
| 2008 | /// Set the least significant BITS and clear the rest. |
| 2009 | static void tcSetLeastSignificantBits(WordType *, unsigned, unsigned bits); |
| 2010 | |
| 2011 | /// debug method |
| 2012 | void dump() const; |
| 2013 | |
| 2014 | /// @} |
| 2015 | }; |
| 2016 | |
| 2017 | /// Magic data for optimising signed division by a constant. |
| 2018 | struct APInt::ms { |
| 2019 | APInt m; ///< magic number |
| 2020 | unsigned s; ///< shift amount |
| 2021 | }; |
| 2022 | |
| 2023 | /// Magic data for optimising unsigned division by a constant. |
| 2024 | struct APInt::mu { |
| 2025 | APInt m; ///< magic number |
| 2026 | bool a; ///< add indicator |
| 2027 | unsigned s; ///< shift amount |
| 2028 | }; |
| 2029 | |
| 2030 | inline bool operator==(uint64_t V1, const APInt &V2) { return V2 == V1; } |
| 2031 | |
| 2032 | inline bool operator!=(uint64_t V1, const APInt &V2) { return V2 != V1; } |
| 2033 | |
| 2034 | /// Unary bitwise complement operator. |
| 2035 | /// |
| 2036 | /// \returns an APInt that is the bitwise complement of \p v. |
| 2037 | inline APInt operator~(APInt v) { |
| 2038 | v.flipAllBits(); |
| 2039 | return v; |
| 2040 | } |
| 2041 | |
| 2042 | inline APInt operator&(APInt a, const APInt &b) { |
| 2043 | a &= b; |
| 2044 | return a; |
| 2045 | } |
| 2046 | |
| 2047 | inline APInt operator&(const APInt &a, APInt &&b) { |
| 2048 | b &= a; |
| 2049 | return std::move(b); |
| 2050 | } |
| 2051 | |
| 2052 | inline APInt operator&(APInt a, uint64_t RHS) { |
| 2053 | a &= RHS; |
| 2054 | return a; |
| 2055 | } |
| 2056 | |
| 2057 | inline APInt operator&(uint64_t LHS, APInt b) { |
| 2058 | b &= LHS; |
| 2059 | return b; |
| 2060 | } |
| 2061 | |
| 2062 | inline APInt operator|(APInt a, const APInt &b) { |
| 2063 | a |= b; |
| 2064 | return a; |
| 2065 | } |
| 2066 | |
| 2067 | inline APInt operator|(const APInt &a, APInt &&b) { |
| 2068 | b |= a; |
| 2069 | return std::move(b); |
| 2070 | } |
| 2071 | |
| 2072 | inline APInt operator|(APInt a, uint64_t RHS) { |
| 2073 | a |= RHS; |
| 2074 | return a; |
| 2075 | } |
| 2076 | |
| 2077 | inline APInt operator|(uint64_t LHS, APInt b) { |
| 2078 | b |= LHS; |
| 2079 | return b; |
| 2080 | } |
| 2081 | |
| 2082 | inline APInt operator^(APInt a, const APInt &b) { |
| 2083 | a ^= b; |
| 2084 | return a; |
| 2085 | } |
| 2086 | |
| 2087 | inline APInt operator^(const APInt &a, APInt &&b) { |
| 2088 | b ^= a; |
| 2089 | return std::move(b); |
| 2090 | } |
| 2091 | |
| 2092 | inline APInt operator^(APInt a, uint64_t RHS) { |
| 2093 | a ^= RHS; |
| 2094 | return a; |
| 2095 | } |
| 2096 | |
| 2097 | inline APInt operator^(uint64_t LHS, APInt b) { |
| 2098 | b ^= LHS; |
| 2099 | return b; |
| 2100 | } |
| 2101 | |
| 2102 | inline raw_ostream &operator<<(raw_ostream &OS, const APInt &I) { |
| 2103 | I.print(OS, true); |
| 2104 | return OS; |
| 2105 | } |
| 2106 | |
| 2107 | inline APInt operator-(APInt v) { |
| 2108 | v.negate(); |
| 2109 | return v; |
| 2110 | } |
| 2111 | |
| 2112 | inline APInt operator+(APInt a, const APInt &b) { |
| 2113 | a += b; |
| 2114 | return a; |
| 2115 | } |
| 2116 | |
| 2117 | inline APInt operator+(const APInt &a, APInt &&b) { |
| 2118 | b += a; |
| 2119 | return std::move(b); |
| 2120 | } |
| 2121 | |
| 2122 | inline APInt operator+(APInt a, uint64_t RHS) { |
| 2123 | a += RHS; |
| 2124 | return a; |
| 2125 | } |
| 2126 | |
| 2127 | inline APInt operator+(uint64_t LHS, APInt b) { |
| 2128 | b += LHS; |
| 2129 | return b; |
| 2130 | } |
| 2131 | |
| 2132 | inline APInt operator-(APInt a, const APInt &b) { |
| 2133 | a -= b; |
| 2134 | return a; |
| 2135 | } |
| 2136 | |
| 2137 | inline APInt operator-(const APInt &a, APInt &&b) { |
| 2138 | b.negate(); |
| 2139 | b += a; |
| 2140 | return std::move(b); |
| 2141 | } |
| 2142 | |
| 2143 | inline APInt operator-(APInt a, uint64_t RHS) { |
| 2144 | a -= RHS; |
| 2145 | return a; |
| 2146 | } |
| 2147 | |
| 2148 | inline APInt operator-(uint64_t LHS, APInt b) { |
| 2149 | b.negate(); |
| 2150 | b += LHS; |
| 2151 | return b; |
| 2152 | } |
| 2153 | |
| 2154 | inline APInt operator*(APInt a, uint64_t RHS) { |
| 2155 | a *= RHS; |
| 2156 | return a; |
| 2157 | } |
| 2158 | |
| 2159 | inline APInt operator*(uint64_t LHS, APInt b) { |
| 2160 | b *= LHS; |
| 2161 | return b; |
| 2162 | } |
| 2163 | |
| 2164 | |
| 2165 | namespace APIntOps { |
| 2166 | |
| 2167 | /// Determine the smaller of two APInts considered to be signed. |
| 2168 | inline const APInt &smin(const APInt &A, const APInt &B) { |
| 2169 | return A.slt(B) ? A : B; |
| 2170 | } |
| 2171 | |
| 2172 | /// Determine the larger of two APInts considered to be signed. |
| 2173 | inline const APInt &smax(const APInt &A, const APInt &B) { |
| 2174 | return A.sgt(B) ? A : B; |
| 2175 | } |
| 2176 | |
| 2177 | /// Determine the smaller of two APInts considered to be unsigned. |
| 2178 | inline const APInt &umin(const APInt &A, const APInt &B) { |
| 2179 | return A.ult(B) ? A : B; |
| 2180 | } |
| 2181 | |
| 2182 | /// Determine the larger of two APInts considered to be unsigned. |
| 2183 | inline const APInt &umax(const APInt &A, const APInt &B) { |
| 2184 | return A.ugt(B) ? A : B; |
| 2185 | } |
| 2186 | |
| 2187 | /// Compute GCD of two unsigned APInt values. |
| 2188 | /// |
| 2189 | /// This function returns the greatest common divisor of the two APInt values |
| 2190 | /// using Stein's algorithm. |
| 2191 | /// |
| 2192 | /// \returns the greatest common divisor of A and B. |
| 2193 | APInt GreatestCommonDivisor(APInt A, APInt B); |
| 2194 | |
| 2195 | /// Converts the given APInt to a double value. |
| 2196 | /// |
| 2197 | /// Treats the APInt as an unsigned value for conversion purposes. |
| 2198 | inline double RoundAPIntToDouble(const APInt &APIVal) { |
| 2199 | return APIVal.roundToDouble(); |
| 2200 | } |
| 2201 | |
| 2202 | /// Converts the given APInt to a double value. |
| 2203 | /// |
| 2204 | /// Treats the APInt as a signed value for conversion purposes. |
| 2205 | inline double RoundSignedAPIntToDouble(const APInt &APIVal) { |
| 2206 | return APIVal.signedRoundToDouble(); |
| 2207 | } |
| 2208 | |
| 2209 | /// Converts the given APInt to a float value. |
| 2210 | inline float RoundAPIntToFloat(const APInt &APIVal) { |
| 2211 | return float(RoundAPIntToDouble(APIVal)); |
| 2212 | } |
| 2213 | |
| 2214 | /// Converts the given APInt to a float value. |
| 2215 | /// |
| 2216 | /// Treats the APInt as a signed value for conversion purposes. |
| 2217 | inline float RoundSignedAPIntToFloat(const APInt &APIVal) { |
| 2218 | return float(APIVal.signedRoundToDouble()); |
| 2219 | } |
| 2220 | |
| 2221 | /// Converts the given double value into a APInt. |
| 2222 | /// |
| 2223 | /// This function convert a double value to an APInt value. |
| 2224 | APInt RoundDoubleToAPInt(double Double, unsigned width); |
| 2225 | |
| 2226 | /// Converts a float value into a APInt. |
| 2227 | /// |
| 2228 | /// Converts a float value into an APInt value. |
| 2229 | inline APInt RoundFloatToAPInt(float Float, unsigned width) { |
| 2230 | return RoundDoubleToAPInt(double(Float), width); |
| 2231 | } |
| 2232 | |
| 2233 | /// Return A unsign-divided by B, rounded by the given rounding mode. |
| 2234 | APInt RoundingUDiv(const APInt &A, const APInt &B, APInt::Rounding RM); |
| 2235 | |
| 2236 | /// Return A sign-divided by B, rounded by the given rounding mode. |
| 2237 | APInt RoundingSDiv(const APInt &A, const APInt &B, APInt::Rounding RM); |
| 2238 | |
| 2239 | /// Let q(n) = An^2 + Bn + C, and BW = bit width of the value range |
| 2240 | /// (e.g. 32 for i32). |
| 2241 | /// This function finds the smallest number n, such that |
| 2242 | /// (a) n >= 0 and q(n) = 0, or |
| 2243 | /// (b) n >= 1 and q(n-1) and q(n), when evaluated in the set of all |
| 2244 | /// integers, belong to two different intervals [Rk, Rk+R), |
| 2245 | /// where R = 2^BW, and k is an integer. |
| 2246 | /// The idea here is to find when q(n) "overflows" 2^BW, while at the |
| 2247 | /// same time "allowing" subtraction. In unsigned modulo arithmetic a |
| 2248 | /// subtraction (treated as addition of negated numbers) would always |
| 2249 | /// count as an overflow, but here we want to allow values to decrease |
| 2250 | /// and increase as long as they are within the same interval. |
| 2251 | /// Specifically, adding of two negative numbers should not cause an |
| 2252 | /// overflow (as long as the magnitude does not exceed the bit width). |
| 2253 | /// On the other hand, given a positive number, adding a negative |
| 2254 | /// number to it can give a negative result, which would cause the |
| 2255 | /// value to go from [-2^BW, 0) to [0, 2^BW). In that sense, zero is |
| 2256 | /// treated as a special case of an overflow. |
| 2257 | /// |
| 2258 | /// This function returns None if after finding k that minimizes the |
| 2259 | /// positive solution to q(n) = kR, both solutions are contained between |
| 2260 | /// two consecutive integers. |
| 2261 | /// |
| 2262 | /// There are cases where q(n) > T, and q(n+1) < T (assuming evaluation |
| 2263 | /// in arithmetic modulo 2^BW, and treating the values as signed) by the |
| 2264 | /// virtue of *signed* overflow. This function will *not* find such an n, |
| 2265 | /// however it may find a value of n satisfying the inequalities due to |
| 2266 | /// an *unsigned* overflow (if the values are treated as unsigned). |
| 2267 | /// To find a solution for a signed overflow, treat it as a problem of |
| 2268 | /// finding an unsigned overflow with a range with of BW-1. |
| 2269 | /// |
| 2270 | /// The returned value may have a different bit width from the input |
| 2271 | /// coefficients. |
| 2272 | Optional<APInt> SolveQuadraticEquationWrap(APInt A, APInt B, APInt C, |
| 2273 | unsigned RangeWidth); |
| 2274 | |
| 2275 | /// Compare two values, and if they are different, return the position of the |
| 2276 | /// most significant bit that is different in the values. |
| 2277 | Optional<unsigned> GetMostSignificantDifferentBit(const APInt &A, |
| 2278 | const APInt &B); |
| 2279 | |
| 2280 | } // End of APIntOps namespace |
| 2281 | |
| 2282 | // See friend declaration above. This additional declaration is required in |
| 2283 | // order to compile LLVM with IBM xlC compiler. |
| 2284 | hash_code hash_value(const APInt &Arg); |
| 2285 | |
| 2286 | /// StoreIntToMemory - Fills the StoreBytes bytes of memory starting from Dst |
| 2287 | /// with the integer held in IntVal. |
| 2288 | void StoreIntToMemory(const APInt &IntVal, uint8_t *Dst, unsigned StoreBytes); |
| 2289 | |
| 2290 | /// LoadIntFromMemory - Loads the integer stored in the LoadBytes bytes starting |
| 2291 | /// from Src into IntVal, which is assumed to be wide enough and to hold zero. |
| 2292 | void LoadIntFromMemory(APInt &IntVal, const uint8_t *Src, unsigned LoadBytes); |
| 2293 | |
| 2294 | /// Provide DenseMapInfo for APInt. |
| 2295 | template <> struct DenseMapInfo<APInt> { |
| 2296 | static inline APInt getEmptyKey() { |
| 2297 | APInt V(nullptr, 0); |
| 2298 | V.U.VAL = 0; |
| 2299 | return V; |
| 2300 | } |
| 2301 | |
| 2302 | static inline APInt getTombstoneKey() { |
| 2303 | APInt V(nullptr, 0); |
| 2304 | V.U.VAL = 1; |
| 2305 | return V; |
| 2306 | } |
| 2307 | |
| 2308 | static unsigned getHashValue(const APInt &Key); |
| 2309 | |
| 2310 | static bool isEqual(const APInt &LHS, const APInt &RHS) { |
| 2311 | return LHS.getBitWidth() == RHS.getBitWidth() && LHS == RHS; |
| 2312 | } |
| 2313 | }; |
| 2314 | |
| 2315 | } // namespace llvm |
| 2316 | |
| 2317 | #endif |