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Differential D68502 Diff 277742 llvm/lib/Analysis/ValueTracking.cpp

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llvm/lib/Analysis/ValueTracking.cpp

Show First 20 Lines • Show All 602 Lines • ▼ Show 20 Lines if (Function *F = CI->getCalledFunction())
case Intrinsic::sideeffect: case Intrinsic::sideeffect:
case Intrinsic::dbg_declare: case Intrinsic::dbg_declare:
case Intrinsic::dbg_value: case Intrinsic::dbg_value:
case Intrinsic::dbg_label: case Intrinsic::dbg_label:
case Intrinsic::invariant_start: case Intrinsic::invariant_start:
case Intrinsic::invariant_end: case Intrinsic::invariant_end:
case Intrinsic::lifetime_start: case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end: case Intrinsic::lifetime_end:
case Intrinsic::noalias_decl:
case Intrinsic::noalias: case Intrinsic::noalias:
case Intrinsic::provenance_noalias:
case Intrinsic::noalias_arg_guard:
case Intrinsic::noalias_copy_guard:
case Intrinsic::objectsize: case Intrinsic::objectsize:
case Intrinsic::ptr_annotation: case Intrinsic::ptr_annotation:
case Intrinsic::var_annotation: case Intrinsic::var_annotation:
return true; return true;
} }
return false; return false;
} }
▲ Show 20 Lines • Show All 3,472 Lines • ▼ Show 20 Lines if (isIntrinsicReturningPointerAliasingArgumentWithoutCapturing(
return Call->getArgOperand(0); return Call->getArgOperand(0);
return nullptr; return nullptr;
} }
bool llvm::isIntrinsicReturningPointerAliasingArgumentWithoutCapturing( bool llvm::isIntrinsicReturningPointerAliasingArgumentWithoutCapturing(
const CallBase *Call, bool MustPreserveNullness) { const CallBase *Call, bool MustPreserveNullness) {
switch (Call->getIntrinsicID()) { switch (Call->getIntrinsicID()) {
case Intrinsic::launder_invariant_group: case Intrinsic::launder_invariant_group:
case Intrinsic::noalias_arg_guard:
case Intrinsic::noalias_copy_guard:
case Intrinsic::strip_invariant_group: case Intrinsic::strip_invariant_group:
case Intrinsic::aarch64_irg: case Intrinsic::aarch64_irg:
case Intrinsic::aarch64_tagp: case Intrinsic::aarch64_tagp:
return true; return true;
case Intrinsic::ptrmask: case Intrinsic::ptrmask:
return !MustPreserveNullness; return !MustPreserveNullness;
default: default:
return false; return false;
Show All 23 Linesstatic bool isSameUnderlyingObjectInLoop(const PHINode *PN,
// ... // ...
if (auto *Load = dyn_cast<LoadInst>(PrevValue)) if (auto *Load = dyn_cast<LoadInst>(PrevValue))
if (!L->isLoopInvariant(Load->getPointerOperand())) if (!L->isLoopInvariant(Load->getPointerOperand()))
return false; return false;
return true; return true;
} }
Value *llvm::GetUnderlyingObject(Value *V, const DataLayout &DL, Value *llvm::GetUnderlyingObject(Value *V, const DataLayout &DL,
unsigned MaxLookup) { unsigned MaxLookup,
SmallVectorImpl<Instruction *> *NoAlias) {
if (!V->getType()->isPointerTy()) if (!V->getType()->isPointerTy())
return V; return V;
for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) { for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) {
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) { if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
V = GEP->getPointerOperand(); V = GEP->getPointerOperand();
} else if (Operator::getOpcode(V) == Instruction::BitCast || } else if (Operator::getOpcode(V) == Instruction::BitCast ||
Operator::getOpcode(V) == Instruction::AddrSpaceCast) { Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
V = cast<Operator>(V)->getOperand(0); V = cast<Operator>(V)->getOperand(0);
if (!V->getType()->isPointerTy()) if (!V->getType()->isPointerTy())
return V; return V;
} else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) { } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
if (GA->isInterposable()) if (GA->isInterposable())
return V; return V;
V = GA->getAliasee(); V = GA->getAliasee();
} else { } else {
if (auto *PHI = dyn_cast<PHINode>(V)) { if (auto *PHI = dyn_cast<PHINode>(V)) {
// Look through single-arg phi nodes created by LCSSA. // Look through single-arg phi nodes created by LCSSA.
if (PHI->getNumIncomingValues() == 1) { if (PHI->getNumIncomingValues() == 1) {
V = PHI->getIncomingValue(0); V = PHI->getIncomingValue(0);
continue; continue;
} }
} else if (auto *Call = dyn_cast<CallBase>(V)) { } else if (auto *Call = dyn_cast<CallBase>(V)) {
if (NoAlias) {
// We are gathering information for ScopedAANoAlias -
// Look through noalias and provenance.noalias intrinsic
if (Call->getIntrinsicID() == Intrinsic::provenance_noalias ||
Call->getIntrinsicID() == Intrinsic::noalias) {
NoAlias->push_back(Call);
V = Call->getArgOperand(0);
continue;
}
// Look trough noalias.arg.guard, and follow the ptr_provenance
if (Call->getIntrinsicID() == Intrinsic::noalias_arg_guard) {
V = Call->getArgOperand(1);
continue;
}
} else {
// We are not gathering information for SCopedAANoAlias -
// Look through noalias.arg.guard and follow the pointer path
if (Call->getIntrinsicID() == Intrinsic::noalias_arg_guard) {
V = Call->getArgOperand(0);
continue;
}
}
// CaptureTracking can know about special capturing properties of some // CaptureTracking can know about special capturing properties of some
// intrinsics like launder.invariant.group, that can't be expressed with // intrinsics like launder.invariant.group, that can't be expressed with
// the attributes, but have properties like returning aliasing pointer. // the attributes, but have properties like returning aliasing pointer.
// Because some analysis may assume that nocaptured pointer is not // Because some analysis may assume that nocaptured pointer is not
// returned from some special intrinsic (because function would have to // returned from some special intrinsic (because function would have to
// be marked with returns attribute), it is crucial to use this function // be marked with returns attribute), it is crucial to use this function
// because it should be in sync with CaptureTracking. Not using it may // because it should be in sync with CaptureTracking. Not using it may
// cause weird miscompilations where 2 aliasing pointers are assumed to // cause weird miscompilations where 2 aliasing pointers are assumed to
Show All 9 Lines for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) {
assert(V->getType()->isPointerTy() && "Unexpected operand type!"); assert(V->getType()->isPointerTy() && "Unexpected operand type!");
} }
return V; return V;
} }
void llvm::GetUnderlyingObjects(const Value *V, void llvm::GetUnderlyingObjects(const Value *V,
SmallVectorImpl<const Value *> &Objects, SmallVectorImpl<const Value *> &Objects,
const DataLayout &DL, LoopInfo *LI, const DataLayout &DL, LoopInfo *LI,
unsigned MaxLookup) { unsigned MaxLookup,
SmallVectorImpl<Instruction *> *NoAlias) {
SmallPtrSet<const Value *, 4> Visited; SmallPtrSet<const Value *, 4> Visited;
SmallVector<const Value *, 4> Worklist; SmallVector<const Value *, 4> Worklist;
Worklist.push_back(V); Worklist.push_back(V);
do { do {
const Value *P = Worklist.pop_back_val(); const Value *P = Worklist.pop_back_val();
P = GetUnderlyingObject(P, DL, MaxLookup); P = GetUnderlyingObject(P, DL, MaxLookup, NoAlias);
if (!Visited.insert(P).second) if (!Visited.insert(P).second)
continue; continue;
if (auto *SI = dyn_cast<SelectInst>(P)) { if (auto *SI = dyn_cast<SelectInst>(P)) {
Worklist.push_back(SI->getTrueValue()); Worklist.push_back(SI->getTrueValue());
Worklist.push_back(SI->getFalseValue()); Worklist.push_back(SI->getFalseValue());
continue; continue;
▲ Show 20 Lines • Show All 2,336 Lines • Show Last 20 Lines