return llvm::EmitGEPOffset(Builder, DL, GEP);
}
-/// Return true if it is desirable to convert a computation from 'From' to 'To'.
+/// Return true if it is desirable to convert an integer computation from a
+/// given bit width to a new bit width.
/// We don't want to convert from a legal to an illegal type for example or from
/// a smaller to a larger illegal type.
-bool InstCombiner::ShouldChangeType(Type *From, Type *To) const {
- assert(From->isIntegerTy() && To->isIntegerTy());
-
- unsigned FromWidth = From->getPrimitiveSizeInBits();
- unsigned ToWidth = To->getPrimitiveSizeInBits();
+bool InstCombiner::ShouldChangeType(unsigned FromWidth,
+ unsigned ToWidth) const {
bool FromLegal = DL.isLegalInteger(FromWidth);
bool ToLegal = DL.isLegalInteger(ToWidth);
return true;
}
+/// Return true if it is desirable to convert a computation from 'From' to 'To'.
+/// We don't want to convert from a legal to an illegal type for example or from
+/// a smaller to a larger illegal type.
+bool InstCombiner::ShouldChangeType(Type *From, Type *To) const {
+ assert(From->isIntegerTy() && To->isIntegerTy());
+
+ unsigned FromWidth = From->getPrimitiveSizeInBits();
+ unsigned ToWidth = To->getPrimitiveSizeInBits();
+ return ShouldChangeType(FromWidth, ToWidth);
+}
+
// Return true, if No Signed Wrap should be maintained for I.
// The No Signed Wrap flag can be kept if the operation "B (I.getOpcode) C",
// where both B and C should be ConstantInts, results in a constant that does
}
}
- GetElementPtrInst *NewGEP = cast<GetElementPtrInst>(Op1->clone());
+ // If not all GEPs are identical we'll have to create a new PHI node.
+ // Check that the old PHI node has only one use so that it will get
+ // removed.
+ if (DI != -1 && !PN->hasOneUse())
+ return nullptr;
+ GetElementPtrInst *NewGEP = cast<GetElementPtrInst>(Op1->clone());
if (DI == -1) {
// All the GEPs feeding the PHI are identical. Clone one down into our
// BB so that it can be merged with the current GEP.
// All the GEPs feeding the PHI differ at a single offset. Clone a GEP
// into the current block so it can be merged, and create a new PHI to
// set that index.
- Instruction *InsertPt = Builder->GetInsertPoint();
- Builder->SetInsertPoint(PN);
- PHINode *NewPN = Builder->CreatePHI(Op1->getOperand(DI)->getType(),
- PN->getNumOperands());
- Builder->SetInsertPoint(InsertPt);
+ PHINode *NewPN;
+ {
+ IRBuilderBase::InsertPointGuard Guard(*Builder);
+ Builder->SetInsertPoint(PN);
+ NewPN = Builder->CreatePHI(Op1->getOperand(DI)->getType(),
+ PN->getNumOperands());
+ }
for (auto &I : PN->operands())
NewPN->addIncoming(cast<GEPOperator>(I)->getOperand(DI),
if (Instruction *I = visitBitCast(*BCI)) {
if (I != BCI) {
I->takeName(BCI);
- BCI->getParent()->getInstList().insert(BCI, I);
+ BCI->getParent()->getInstList().insert(BCI->getIterator(), I);
ReplaceInstUsesWith(*BCI, I);
}
return &GEP;
// We need to insert these at the location of the old load, not at that of
// the extractvalue.
- Builder->SetInsertPoint(L->getParent(), L);
+ Builder->SetInsertPoint(L);
Value *GEP = Builder->CreateInBoundsGEP(L->getType(),
L->getPointerOperand(), Indices);
// Returning the load directly will cause the main loop to insert it in
case EHPersonality::MSVC_X86SEH:
case EHPersonality::MSVC_Win64SEH:
case EHPersonality::MSVC_CXX:
+ case EHPersonality::CoreCLR:
return TypeInfo->isNullValue();
}
llvm_unreachable("invalid enum");
// We can only sink load instructions if there is nothing between the load and
// the end of block that could change the value.
if (I->mayReadFromMemory()) {
- for (BasicBlock::iterator Scan = I, E = I->getParent()->end();
+ for (BasicBlock::iterator Scan = I->getIterator(),
+ E = I->getParent()->end();
Scan != E; ++Scan)
if (Scan->mayWriteToMemory())
return false;
}
BasicBlock::iterator InsertPos = DestBlock->getFirstInsertionPt();
- I->moveBefore(InsertPos);
+ I->moveBefore(&*InsertPos);
++NumSunkInst;
return true;
}
}
}
+ // In general, it is possible for computeKnownBits to determine all bits in a
+ // value even when the operands are not all constants.
+ if (!I->use_empty() && I->getType()->isIntegerTy()) {
+ unsigned BitWidth = I->getType()->getScalarSizeInBits();
+ APInt KnownZero(BitWidth, 0);
+ APInt KnownOne(BitWidth, 0);
+ computeKnownBits(I, KnownZero, KnownOne, /*Depth*/0, I);
+ if ((KnownZero | KnownOne).isAllOnesValue()) {
+ Constant *C = ConstantInt::get(I->getContext(), KnownOne);
+ DEBUG(dbgs() << "IC: ConstFold (all bits known) to: " << *C <<
+ " from: " << *I << '\n');
+
+ // Add operands to the worklist.
+ ReplaceInstUsesWith(*I, C);
+ ++NumConstProp;
+ EraseInstFromFunction(*I);
+ MadeIRChange = true;
+ continue;
+ }
+ }
+
// See if we can trivially sink this instruction to a successor basic block.
if (I->hasOneUse()) {
BasicBlock *BB = I->getParent();
}
// Now that we have an instruction, try combining it to simplify it.
- Builder->SetInsertPoint(I->getParent(), I);
+ Builder->SetInsertPoint(I);
Builder->SetCurrentDebugLocation(I->getDebugLoc());
#ifndef NDEBUG
// Insert the new instruction into the basic block...
BasicBlock *InstParent = I->getParent();
- BasicBlock::iterator InsertPos = I;
+ BasicBlock::iterator InsertPos = I->getIterator();
// If we replace a PHI with something that isn't a PHI, fix up the
// insertion point.
continue;
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
- Instruction *Inst = BBI++;
+ Instruction *Inst = &*BBI++;
// DCE instruction if trivially dead.
if (isInstructionTriviallyDead(Inst, TLI)) {
// of the function down. This jives well with the way that it adds all uses
// of instructions to the worklist after doing a transformation, thus avoiding
// some N^2 behavior in pathological cases.
- ICWorklist.AddInitialGroup(&InstrsForInstCombineWorklist[0],
- InstrsForInstCombineWorklist.size());
+ ICWorklist.AddInitialGroup(InstrsForInstCombineWorklist);
return MadeIRChange;
}
// track of which blocks we visit.
SmallPtrSet<BasicBlock *, 64> Visited;
MadeIRChange |=
- AddReachableCodeToWorklist(F.begin(), DL, Visited, ICWorklist, TLI);
+ AddReachableCodeToWorklist(&F.front(), DL, Visited, ICWorklist, TLI);
// Do a quick scan over the function. If we find any blocks that are
// unreachable, remove any instructions inside of them. This prevents
// the instcombine code from having to deal with some bad special cases.
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
- if (Visited.count(BB))
+ if (Visited.count(&*BB))
continue;
// Delete the instructions backwards, as it has a reduced likelihood of
Instruction *EndInst = BB->getTerminator(); // Last not to be deleted.
while (EndInst != BB->begin()) {
// Delete the next to last instruction.
- BasicBlock::iterator I = EndInst;
- Instruction *Inst = --I;
+ Instruction *Inst = &*--EndInst->getIterator();
if (!Inst->use_empty())
Inst->replaceAllUsesWith(UndefValue::get(Inst->getType()));
if (Inst->isEHPad()) {