#include "llvm/Transforms/Utils/Local.h"
#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/EHPersonalities.h"
#include "llvm/Analysis/InstructionSimplify.h"
-#include "llvm/Analysis/LibCallSemantics.h"
#include "llvm/Analysis/MemoryBuiltins.h"
+#include "llvm/Analysis/LazyValueInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
BasicBlock *BB = SI->getParent();
// Remove entries from PHI nodes which we no longer branch to...
- for (unsigned i = 0, e = SI->getNumSuccessors(); i != e; ++i) {
+ for (BasicBlock *Succ : SI->successors()) {
// Found case matching a constant operand?
- BasicBlock *Succ = SI->getSuccessor(i);
if (Succ == TheOnlyDest)
TheOnlyDest = nullptr; // Don't modify the first branch to TheOnlyDest
else
SIDef->getValue().getZExtValue()));
}
+ // Update make.implicit metadata to the newly-created conditional branch.
+ MDNode *MakeImplicitMD = SI->getMetadata(LLVMContext::MD_make_implicit);
+ if (MakeImplicitMD)
+ NewBr->setMetadata(LLVMContext::MD_make_implicit, MakeImplicitMD);
+
// Delete the old switch.
SI->eraseFromParent();
return true;
const TargetLibraryInfo *TLI) {
if (!I->use_empty() || isa<TerminatorInst>(I)) return false;
- // We don't want the landingpad instruction removed by anything this general.
- if (isa<LandingPadInst>(I))
+ // We don't want the landingpad-like instructions removed by anything this
+ // general.
+ if (I->isEHPad())
return false;
// We don't want debug info removed by anything this general, unless
return false;
}
+static bool
+simplifyAndDCEInstruction(Instruction *I,
+ SmallSetVector<Instruction *, 16> &WorkList,
+ const DataLayout &DL,
+ const TargetLibraryInfo *TLI) {
+ if (isInstructionTriviallyDead(I, TLI)) {
+ // Null out all of the instruction's operands to see if any operand becomes
+ // dead as we go.
+ for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
+ Value *OpV = I->getOperand(i);
+ I->setOperand(i, nullptr);
+
+ if (!OpV->use_empty() || I == OpV)
+ continue;
+
+ // If the operand is an instruction that became dead as we nulled out the
+ // operand, and if it is 'trivially' dead, delete it in a future loop
+ // iteration.
+ if (Instruction *OpI = dyn_cast<Instruction>(OpV))
+ if (isInstructionTriviallyDead(OpI, TLI))
+ WorkList.insert(OpI);
+ }
+
+ I->eraseFromParent();
+
+ return true;
+ }
+
+ if (Value *SimpleV = SimplifyInstruction(I, DL)) {
+ // Add the users to the worklist. CAREFUL: an instruction can use itself,
+ // in the case of a phi node.
+ for (User *U : I->users())
+ if (U != I)
+ WorkList.insert(cast<Instruction>(U));
+
+ // Replace the instruction with its simplified value.
+ I->replaceAllUsesWith(SimpleV);
+ I->eraseFromParent();
+ return true;
+ }
+ return false;
+}
+
/// SimplifyInstructionsInBlock - Scan the specified basic block and try to
/// simplify any instructions in it and recursively delete dead instructions.
///
bool llvm::SimplifyInstructionsInBlock(BasicBlock *BB,
const TargetLibraryInfo *TLI) {
bool MadeChange = false;
+ const DataLayout &DL = BB->getModule()->getDataLayout();
#ifndef NDEBUG
// In debug builds, ensure that the terminator of the block is never replaced
// or deleted by these simplifications. The idea of simplification is that it
// cannot introduce new instructions, and there is no way to replace the
// terminator of a block without introducing a new instruction.
- AssertingVH<Instruction> TerminatorVH(--BB->end());
+ AssertingVH<Instruction> TerminatorVH(&BB->back());
#endif
- for (BasicBlock::iterator BI = BB->begin(), E = --BB->end(); BI != E; ) {
+ SmallSetVector<Instruction *, 16> WorkList;
+ // Iterate over the original function, only adding insts to the worklist
+ // if they actually need to be revisited. This avoids having to pre-init
+ // the worklist with the entire function's worth of instructions.
+ for (BasicBlock::iterator BI = BB->begin(), E = std::prev(BB->end()); BI != E;) {
assert(!BI->isTerminator());
- Instruction *Inst = BI++;
+ Instruction *I = &*BI;
+ ++BI;
- WeakVH BIHandle(BI);
- if (recursivelySimplifyInstruction(Inst, TLI)) {
- MadeChange = true;
- if (BIHandle != BI)
- BI = BB->begin();
- continue;
- }
+ // We're visiting this instruction now, so make sure it's not in the
+ // worklist from an earlier visit.
+ if (!WorkList.count(I))
+ MadeChange |= simplifyAndDCEInstruction(I, WorkList, DL, TLI);
+ }
- MadeChange |= RecursivelyDeleteTriviallyDeadInstructions(Inst, TLI);
- if (BIHandle != BI)
- BI = BB->begin();
+ while (!WorkList.empty()) {
+ Instruction *I = WorkList.pop_back_val();
+ MadeChange |= simplifyAndDCEInstruction(I, WorkList, DL, TLI);
}
return MadeChange;
}
// Copy over any phi, debug or lifetime instruction.
BB->getTerminator()->eraseFromParent();
- Succ->getInstList().splice(Succ->getFirstNonPHI(), BB->getInstList());
+ Succ->getInstList().splice(Succ->getFirstNonPHI()->getIterator(),
+ BB->getInstList());
} else {
while (PHINode *PN = dyn_cast<PHINode>(&BB->front())) {
// We explicitly check for such uses in CanPropagatePredecessorsForPHIs.
/// orders them so it usually won't matter.
///
bool llvm::EliminateDuplicatePHINodes(BasicBlock *BB) {
- bool Changed = false;
-
// This implementation doesn't currently consider undef operands
// specially. Theoretically, two phis which are identical except for
// one having an undef where the other doesn't could be collapsed.
- // Map from PHI hash values to PHI nodes. If multiple PHIs have
- // the same hash value, the element is the first PHI in the
- // linked list in CollisionMap.
- DenseMap<uintptr_t, PHINode *> HashMap;
+ struct PHIDenseMapInfo {
+ static PHINode *getEmptyKey() {
+ return DenseMapInfo<PHINode *>::getEmptyKey();
+ }
+ static PHINode *getTombstoneKey() {
+ return DenseMapInfo<PHINode *>::getTombstoneKey();
+ }
+ static unsigned getHashValue(PHINode *PN) {
+ // Compute a hash value on the operands. Instcombine will likely have
+ // sorted them, which helps expose duplicates, but we have to check all
+ // the operands to be safe in case instcombine hasn't run.
+ return static_cast<unsigned>(hash_combine(
+ hash_combine_range(PN->value_op_begin(), PN->value_op_end()),
+ hash_combine_range(PN->block_begin(), PN->block_end())));
+ }
+ static bool isEqual(PHINode *LHS, PHINode *RHS) {
+ if (LHS == getEmptyKey() || LHS == getTombstoneKey() ||
+ RHS == getEmptyKey() || RHS == getTombstoneKey())
+ return LHS == RHS;
+ return LHS->isIdenticalTo(RHS);
+ }
+ };
- // Maintain linked lists of PHI nodes with common hash values.
- DenseMap<PHINode *, PHINode *> CollisionMap;
+ // Set of unique PHINodes.
+ DenseSet<PHINode *, PHIDenseMapInfo> PHISet;
// Examine each PHI.
- for (BasicBlock::iterator I = BB->begin();
- PHINode *PN = dyn_cast<PHINode>(I++); ) {
- // Compute a hash value on the operands. Instcombine will likely have sorted
- // them, which helps expose duplicates, but we have to check all the
- // operands to be safe in case instcombine hasn't run.
- uintptr_t Hash = 0;
- // This hash algorithm is quite weak as hash functions go, but it seems
- // to do a good enough job for this particular purpose, and is very quick.
- for (User::op_iterator I = PN->op_begin(), E = PN->op_end(); I != E; ++I) {
- Hash ^= reinterpret_cast<uintptr_t>(static_cast<Value *>(*I));
- Hash = (Hash << 7) | (Hash >> (sizeof(uintptr_t) * CHAR_BIT - 7));
- }
- for (PHINode::block_iterator I = PN->block_begin(), E = PN->block_end();
- I != E; ++I) {
- Hash ^= reinterpret_cast<uintptr_t>(static_cast<BasicBlock *>(*I));
- Hash = (Hash << 7) | (Hash >> (sizeof(uintptr_t) * CHAR_BIT - 7));
- }
- // Avoid colliding with the DenseMap sentinels ~0 and ~0-1.
- Hash >>= 1;
- // If we've never seen this hash value before, it's a unique PHI.
- std::pair<DenseMap<uintptr_t, PHINode *>::iterator, bool> Pair =
- HashMap.insert(std::make_pair(Hash, PN));
- if (Pair.second) continue;
- // Otherwise it's either a duplicate or a hash collision.
- for (PHINode *OtherPN = Pair.first->second; ; ) {
- if (OtherPN->isIdenticalTo(PN)) {
- // A duplicate. Replace this PHI with its duplicate.
- PN->replaceAllUsesWith(OtherPN);
- PN->eraseFromParent();
- Changed = true;
- break;
- }
- // A non-duplicate hash collision.
- DenseMap<PHINode *, PHINode *>::iterator I = CollisionMap.find(OtherPN);
- if (I == CollisionMap.end()) {
- // Set this PHI to be the head of the linked list of colliding PHIs.
- PHINode *Old = Pair.first->second;
- Pair.first->second = PN;
- CollisionMap[PN] = Old;
- break;
- }
- // Proceed to the next PHI in the list.
- OtherPN = I->second;
+ bool Changed = false;
+ for (auto I = BB->begin(); PHINode *PN = dyn_cast<PHINode>(I++);) {
+ auto Inserted = PHISet.insert(PN);
+ if (!Inserted.second) {
+ // A duplicate. Replace this PHI with its duplicate.
+ PN->replaceAllUsesWith(*Inserted.first);
+ PN->eraseFromParent();
+ Changed = true;
+
+ // The RAUW can change PHIs that we already visited. Start over from the
+ // beginning.
+ PHISet.clear();
+ I = BB->begin();
}
}
static unsigned enforceKnownAlignment(Value *V, unsigned Align,
unsigned PrefAlign,
const DataLayout &DL) {
+ assert(PrefAlign > Align);
+
V = V->stripPointerCasts();
if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
+ // TODO: ideally, computeKnownBits ought to have used
+ // AllocaInst::getAlignment() in its computation already, making
+ // the below max redundant. But, as it turns out,
+ // stripPointerCasts recurses through infinite layers of bitcasts,
+ // while computeKnownBits is not allowed to traverse more than 6
+ // levels.
+ Align = std::max(AI->getAlignment(), Align);
+ if (PrefAlign <= Align)
+ return Align;
+
// If the preferred alignment is greater than the natural stack alignment
// then don't round up. This avoids dynamic stack realignment.
if (DL.exceedsNaturalStackAlignment(PrefAlign))
return Align;
- // If there is a requested alignment and if this is an alloca, round up.
- if (AI->getAlignment() >= PrefAlign)
- return AI->getAlignment();
AI->setAlignment(PrefAlign);
return PrefAlign;
}
if (auto *GO = dyn_cast<GlobalObject>(V)) {
- // If there is a large requested alignment and we can, bump up the alignment
- // of the global.
- if (GO->isDeclaration())
+ // TODO: as above, this shouldn't be necessary.
+ Align = std::max(GO->getAlignment(), Align);
+ if (PrefAlign <= Align)
return Align;
- // If the memory we set aside for the global may not be the memory used by
- // the final program then it is impossible for us to reliably enforce the
- // preferred alignment.
- if (GO->isWeakForLinker())
+
+ // If there is a large requested alignment and we can, bump up the alignment
+ // of the global. If the memory we set aside for the global may not be the
+ // memory used by the final program then it is impossible for us to reliably
+ // enforce the preferred alignment.
+ if (!GO->canIncreaseAlignment())
return Align;
- if (GO->getAlignment() >= PrefAlign)
- return GO->getAlignment();
- // We can only increase the alignment of the global if it has no alignment
- // specified or if it is not assigned a section. If it is assigned a
- // section, the global could be densely packed with other objects in the
- // section, increasing the alignment could cause padding issues.
- if (!GO->hasSection() || GO->getAlignment() == 0)
- GO->setAlignment(PrefAlign);
- return GO->getAlignment();
+ GO->setAlignment(PrefAlign);
+ return PrefAlign;
}
return Align;
ExtendedArg = dyn_cast<Argument>(ZExt->getOperand(0));
if (SExtInst *SExt = dyn_cast<SExtInst>(SI->getOperand(0)))
ExtendedArg = dyn_cast<Argument>(SExt->getOperand(0));
- if (ExtendedArg)
- Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar, DIExpr,
+ if (ExtendedArg) {
+ // We're now only describing a subset of the variable. The piece we're
+ // describing will always be smaller than the variable size, because
+ // VariableSize == Size of Alloca described by DDI. Since SI stores
+ // to the alloca described by DDI, if it's first operand is an extend,
+ // we're guaranteed that before extension, the value was narrower than
+ // the size of the alloca, hence the size of the described variable.
+ SmallVector<uint64_t, 3> NewDIExpr;
+ unsigned PieceOffset = 0;
+ // If this already is a bit piece, we drop the bit piece from the expression
+ // and record the offset.
+ if (DIExpr->isBitPiece()) {
+ NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end()-3);
+ PieceOffset = DIExpr->getBitPieceOffset();
+ } else {
+ NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end());
+ }
+ NewDIExpr.push_back(dwarf::DW_OP_bit_piece);
+ NewDIExpr.push_back(PieceOffset); //Offset
+ const DataLayout &DL = DDI->getModule()->getDataLayout();
+ NewDIExpr.push_back(DL.getTypeSizeInBits(ExtendedArg->getType())); // Size
+ Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar,
+ Builder.createExpression(NewDIExpr),
DDI->getDebugLoc(), SI);
+ }
else
Builder.insertDbgValueIntrinsic(SI->getOperand(0), 0, DIVar, DIExpr,
DDI->getDebugLoc(), SI);
if (LdStHasDebugValue(DIVar, LI))
return true;
- Builder.insertDbgValueIntrinsic(LI->getOperand(0), 0, DIVar, DIExpr,
- DDI->getDebugLoc(), LI);
+ // We are now tracking the loaded value instead of the address. In the
+ // future if multi-location support is added to the IR, it might be
+ // preferable to keep tracking both the loaded value and the original
+ // address in case the alloca can not be elided.
+ Instruction *DbgValue = Builder.insertDbgValueIntrinsic(
+ LI, 0, DIVar, DIExpr, DDI->getDebugLoc(), (Instruction *)nullptr);
+ DbgValue->insertAfter(LI);
return true;
}
DIBuilder DIB(*F.getParent(), /*AllowUnresolved*/ false);
SmallVector<DbgDeclareInst *, 4> Dbgs;
for (auto &FI : F)
- for (BasicBlock::iterator BI : FI)
- if (auto DDI = dyn_cast<DbgDeclareInst>(BI))
+ for (Instruction &BI : FI)
+ if (auto DDI = dyn_cast<DbgDeclareInst>(&BI))
Dbgs.push_back(DDI);
if (Dbgs.empty())
// This is a call by-value or some other instruction that
// takes a pointer to the variable. Insert a *value*
// intrinsic that describes the alloca.
+ SmallVector<uint64_t, 1> NewDIExpr;
+ auto *DIExpr = DDI->getExpression();
+ NewDIExpr.push_back(dwarf::DW_OP_deref);
+ NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end());
DIB.insertDbgValueIntrinsic(AI, 0, DDI->getVariable(),
- DDI->getExpression(), DDI->getDebugLoc(),
- CI);
+ DIB.createExpression(NewDIExpr),
+ DDI->getDebugLoc(), CI);
}
DDI->eraseFromParent();
}
return nullptr;
}
-bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
- DIBuilder &Builder, bool Deref) {
- DbgDeclareInst *DDI = FindAllocaDbgDeclare(AI);
+bool llvm::replaceDbgDeclare(Value *Address, Value *NewAddress,
+ Instruction *InsertBefore, DIBuilder &Builder,
+ bool Deref, int Offset) {
+ DbgDeclareInst *DDI = FindAllocaDbgDeclare(Address);
if (!DDI)
return false;
DebugLoc Loc = DDI->getDebugLoc();
auto *DIExpr = DDI->getExpression();
assert(DIVar && "Missing variable");
- if (Deref) {
+ if (Deref || Offset) {
// Create a copy of the original DIDescriptor for user variable, prepending
// "deref" operation to a list of address elements, as new llvm.dbg.declare
// will take a value storing address of the memory for variable, not
// alloca itself.
SmallVector<uint64_t, 4> NewDIExpr;
- NewDIExpr.push_back(dwarf::DW_OP_deref);
+ if (Deref)
+ NewDIExpr.push_back(dwarf::DW_OP_deref);
+ if (Offset > 0) {
+ NewDIExpr.push_back(dwarf::DW_OP_plus);
+ NewDIExpr.push_back(Offset);
+ } else if (Offset < 0) {
+ NewDIExpr.push_back(dwarf::DW_OP_minus);
+ NewDIExpr.push_back(-Offset);
+ }
if (DIExpr)
NewDIExpr.append(DIExpr->elements_begin(), DIExpr->elements_end());
DIExpr = Builder.createExpression(NewDIExpr);
}
- // Insert llvm.dbg.declare in the same basic block as the original alloca,
- // and remove old llvm.dbg.declare.
- BasicBlock *BB = AI->getParent();
- Builder.insertDeclare(NewAllocaAddress, DIVar, DIExpr, Loc, BB);
+ // Insert llvm.dbg.declare immediately after the original alloca, and remove
+ // old llvm.dbg.declare.
+ Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
DDI->eraseFromParent();
return true;
}
-/// changeToUnreachable - Insert an unreachable instruction before the specified
-/// instruction, making it and the rest of the code in the block dead.
-static void changeToUnreachable(Instruction *I, bool UseLLVMTrap) {
+bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
+ DIBuilder &Builder, bool Deref, int Offset) {
+ return replaceDbgDeclare(AI, NewAllocaAddress, AI->getNextNode(), Builder,
+ Deref, Offset);
+}
+
+void llvm::changeToUnreachable(Instruction *I, bool UseLLVMTrap) {
BasicBlock *BB = I->getParent();
// Loop over all of the successors, removing BB's entry from any PHI
// nodes.
new UnreachableInst(I->getContext(), I);
// All instructions after this are dead.
- BasicBlock::iterator BBI = I, BBE = BB->end();
+ BasicBlock::iterator BBI = I->getIterator(), BBE = BB->end();
while (BBI != BBE) {
if (!BBI->use_empty())
BBI->replaceAllUsesWith(UndefValue::get(BBI->getType()));
/// changeToCall - Convert the specified invoke into a normal call.
static void changeToCall(InvokeInst *II) {
- SmallVector<Value*, 8> Args(II->op_begin(), II->op_end() - 3);
- CallInst *NewCall = CallInst::Create(II->getCalledValue(), Args, "", II);
+ SmallVector<Value*, 8> Args(II->arg_begin(), II->arg_end());
+ SmallVector<OperandBundleDef, 1> OpBundles;
+ II->getOperandBundlesAsDefs(OpBundles);
+ CallInst *NewCall = CallInst::Create(II->getCalledValue(), Args, OpBundles,
+ "", II);
NewCall->takeName(II);
NewCall->setCallingConv(II->getCallingConv());
NewCall->setAttributes(II->getAttributes());
II->eraseFromParent();
}
-static bool markAliveBlocks(BasicBlock *BB,
+static bool markAliveBlocks(Function &F,
SmallPtrSetImpl<BasicBlock*> &Reachable) {
SmallVector<BasicBlock*, 128> Worklist;
+ BasicBlock *BB = &F.front();
Worklist.push_back(BB);
Reachable.insert(BB);
bool Changed = false;
if (MakeUnreachable) {
// Don't insert a call to llvm.trap right before the unreachable.
- changeToUnreachable(BBI, false);
+ changeToUnreachable(&*BBI, false);
Changed = true;
break;
}
++BBI;
if (!isa<UnreachableInst>(BBI)) {
// Don't insert a call to llvm.trap right before the unreachable.
- changeToUnreachable(BBI, false);
+ changeToUnreachable(&*BBI, false);
Changed = true;
}
break;
}
}
- // Turn invokes that call 'nounwind' functions into ordinary calls.
- if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator())) {
+ TerminatorInst *Terminator = BB->getTerminator();
+ if (auto *II = dyn_cast<InvokeInst>(Terminator)) {
+ // Turn invokes that call 'nounwind' functions into ordinary calls.
Value *Callee = II->getCalledValue();
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
changeToUnreachable(II, true);
Changed = true;
- } else if (II->doesNotThrow() && canSimplifyInvokeNoUnwind(II)) {
+ } else if (II->doesNotThrow() && canSimplifyInvokeNoUnwind(&F)) {
if (II->use_empty() && II->onlyReadsMemory()) {
// jump to the normal destination branch.
BranchInst::Create(II->getNormalDest(), II);
changeToCall(II);
Changed = true;
}
+ } else if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(Terminator)) {
+ // Remove catchpads which cannot be reached.
+ struct CatchPadDenseMapInfo {
+ static CatchPadInst *getEmptyKey() {
+ return DenseMapInfo<CatchPadInst *>::getEmptyKey();
+ }
+ static CatchPadInst *getTombstoneKey() {
+ return DenseMapInfo<CatchPadInst *>::getTombstoneKey();
+ }
+ static unsigned getHashValue(CatchPadInst *CatchPad) {
+ return static_cast<unsigned>(hash_combine_range(
+ CatchPad->value_op_begin(), CatchPad->value_op_end()));
+ }
+ static bool isEqual(CatchPadInst *LHS, CatchPadInst *RHS) {
+ if (LHS == getEmptyKey() || LHS == getTombstoneKey() ||
+ RHS == getEmptyKey() || RHS == getTombstoneKey())
+ return LHS == RHS;
+ return LHS->isIdenticalTo(RHS);
+ }
+ };
+
+ // Set of unique CatchPads.
+ SmallDenseMap<CatchPadInst *, detail::DenseSetEmpty, 4,
+ CatchPadDenseMapInfo, detail::DenseSetPair<CatchPadInst *>>
+ HandlerSet;
+ detail::DenseSetEmpty Empty;
+ for (CatchSwitchInst::handler_iterator I = CatchSwitch->handler_begin(),
+ E = CatchSwitch->handler_end();
+ I != E; ++I) {
+ BasicBlock *HandlerBB = *I;
+ auto *CatchPad = cast<CatchPadInst>(HandlerBB->getFirstNonPHI());
+ if (!HandlerSet.insert({CatchPad, Empty}).second) {
+ CatchSwitch->removeHandler(I);
+ --I;
+ --E;
+ Changed = true;
+ }
+ }
}
Changed |= ConstantFoldTerminator(BB, true);
return Changed;
}
+void llvm::removeUnwindEdge(BasicBlock *BB) {
+ TerminatorInst *TI = BB->getTerminator();
+
+ if (auto *II = dyn_cast<InvokeInst>(TI)) {
+ changeToCall(II);
+ return;
+ }
+
+ TerminatorInst *NewTI;
+ BasicBlock *UnwindDest;
+
+ if (auto *CRI = dyn_cast<CleanupReturnInst>(TI)) {
+ NewTI = CleanupReturnInst::Create(CRI->getCleanupPad(), nullptr, CRI);
+ UnwindDest = CRI->getUnwindDest();
+ } else if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(TI)) {
+ auto *NewCatchSwitch = CatchSwitchInst::Create(
+ CatchSwitch->getParentPad(), nullptr, CatchSwitch->getNumHandlers(),
+ CatchSwitch->getName(), CatchSwitch);
+ for (BasicBlock *PadBB : CatchSwitch->handlers())
+ NewCatchSwitch->addHandler(PadBB);
+
+ NewTI = NewCatchSwitch;
+ UnwindDest = CatchSwitch->getUnwindDest();
+ } else {
+ llvm_unreachable("Could not find unwind successor");
+ }
+
+ NewTI->takeName(TI);
+ NewTI->setDebugLoc(TI->getDebugLoc());
+ UnwindDest->removePredecessor(BB);
+ TI->replaceAllUsesWith(NewTI);
+ TI->eraseFromParent();
+}
+
/// removeUnreachableBlocksFromFn - Remove blocks that are not reachable, even
/// if they are in a dead cycle. Return true if a change was made, false
/// otherwise.
-bool llvm::removeUnreachableBlocks(Function &F) {
+bool llvm::removeUnreachableBlocks(Function &F, LazyValueInfo *LVI) {
SmallPtrSet<BasicBlock*, 128> Reachable;
- bool Changed = markAliveBlocks(F.begin(), Reachable);
+ bool Changed = markAliveBlocks(F, Reachable);
// If there are unreachable blocks in the CFG...
if (Reachable.size() == F.size())
// Loop over all of the basic blocks that are not reachable, dropping all of
// their internal references...
for (Function::iterator BB = ++F.begin(), E = F.end(); BB != E; ++BB) {
- if (Reachable.count(BB))
+ if (Reachable.count(&*BB))
continue;
- for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
+ for (succ_iterator SI = succ_begin(&*BB), SE = succ_end(&*BB); SI != SE;
+ ++SI)
if (Reachable.count(*SI))
- (*SI)->removePredecessor(BB);
+ (*SI)->removePredecessor(&*BB);
+ if (LVI)
+ LVI->eraseBlock(&*BB);
BB->dropAllReferences();
}
for (Function::iterator I = ++F.begin(); I != F.end();)
- if (!Reachable.count(I))
+ if (!Reachable.count(&*I))
I = F.getBasicBlockList().erase(I);
else
++I;
return true;
}
-void llvm::combineMetadata(Instruction *K, const Instruction *J, ArrayRef<unsigned> KnownIDs) {
+void llvm::combineMetadata(Instruction *K, const Instruction *J,
+ ArrayRef<unsigned> KnownIDs) {
SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
- K->dropUnknownMetadata(KnownIDs);
+ K->dropUnknownNonDebugMetadata(KnownIDs);
K->getAllMetadataOtherThanDebugLoc(Metadata);
for (unsigned i = 0, n = Metadata.size(); i < n; ++i) {
unsigned Kind = Metadata[i].first;
// Only set the !nonnull if it is present in both instructions.
K->setMetadata(Kind, JMD);
break;
+ case LLVMContext::MD_invariant_group:
+ // Preserve !invariant.group in K.
+ break;
+ case LLVMContext::MD_align:
+ K->setMetadata(Kind,
+ MDNode::getMostGenericAlignmentOrDereferenceable(JMD, KMD));
+ break;
+ case LLVMContext::MD_dereferenceable:
+ case LLVMContext::MD_dereferenceable_or_null:
+ K->setMetadata(Kind,
+ MDNode::getMostGenericAlignmentOrDereferenceable(JMD, KMD));
+ break;
}
}
+ // Set !invariant.group from J if J has it. If both instructions have it
+ // then we will just pick it from J - even when they are different.
+ // Also make sure that K is load or store - f.e. combining bitcast with load
+ // could produce bitcast with invariant.group metadata, which is invalid.
+ // FIXME: we should try to preserve both invariant.group md if they are
+ // different, but right now instruction can only have one invariant.group.
+ if (auto *JMD = J->getMetadata(LLVMContext::MD_invariant_group))
+ if (isa<LoadInst>(K) || isa<StoreInst>(K))
+ K->setMetadata(LLVMContext::MD_invariant_group, JMD);
}
unsigned llvm::replaceDominatedUsesWith(Value *From, Value *To,
}
return Count;
}
+
+unsigned llvm::replaceDominatedUsesWith(Value *From, Value *To,
+ DominatorTree &DT,
+ const BasicBlock *BB) {
+ assert(From->getType() == To->getType());
+
+ unsigned Count = 0;
+ for (Value::use_iterator UI = From->use_begin(), UE = From->use_end();
+ UI != UE;) {
+ Use &U = *UI++;
+ auto *I = cast<Instruction>(U.getUser());
+ if (DT.dominates(BB, I->getParent())) {
+ U.set(To);
+ DEBUG(dbgs() << "Replace dominated use of '" << From->getName() << "' as "
+ << *To << " in " << *U << "\n");
+ ++Count;
+ }
+ }
+ return Count;
+}
+
+bool llvm::callsGCLeafFunction(ImmutableCallSite CS) {
+ if (isa<IntrinsicInst>(CS.getInstruction()))
+ // Most LLVM intrinsics are things which can never take a safepoint.
+ // As a result, we don't need to have the stack parsable at the
+ // callsite. This is a highly useful optimization since intrinsic
+ // calls are fairly prevalent, particularly in debug builds.
+ return true;
+
+ // Check if the function is specifically marked as a gc leaf function.
+ if (CS.hasFnAttr("gc-leaf-function"))
+ return true;
+ if (const Function *F = CS.getCalledFunction())
+ return F->hasFnAttribute("gc-leaf-function");
+
+ return false;
+}
projects / oota-llvm.git / blobdiff