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-rw-r--r--lib/Transforms/InstCombine/InstructionCombining.cpp28
1 files changed, 16 insertions, 12 deletions
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 37123d0..7a84598 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -76,7 +76,6 @@ INITIALIZE_PASS(InstCombiner, "instcombine",
"Combine redundant instructions", false, false)
void InstCombiner::getAnalysisUsage(AnalysisUsage &AU) const {
- AU.addPreservedID(LCSSAID);
AU.setPreservesCFG();
}
@@ -600,8 +599,7 @@ Instruction *InstCombiner::FoldOpIntoPhi(Instruction &I) {
}
// Okay, we can do the transformation: create the new PHI node.
- PHINode *NewPN = PHINode::Create(I.getType(), "");
- NewPN->reserveOperandSpace(PN->getNumOperands()/2);
+ PHINode *NewPN = PHINode::Create(I.getType(), PN->getNumIncomingValues(), "");
InsertNewInstBefore(NewPN, *PN);
NewPN->takeName(PN);
@@ -850,22 +848,23 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
GetElementPtrInst::Create(Src->getOperand(0), Indices.begin(),
Indices.end(), GEP.getName());
}
-
+
// Handle gep(bitcast x) and gep(gep x, 0, 0, 0).
Value *StrippedPtr = PtrOp->stripPointerCasts();
- if (StrippedPtr != PtrOp) {
- const PointerType *StrippedPtrTy =cast<PointerType>(StrippedPtr->getType());
+ const PointerType *StrippedPtrTy =cast<PointerType>(StrippedPtr->getType());
+ if (StrippedPtr != PtrOp &&
+ StrippedPtrTy->getAddressSpace() == GEP.getPointerAddressSpace()) {
bool HasZeroPointerIndex = false;
if (ConstantInt *C = dyn_cast<ConstantInt>(GEP.getOperand(1)))
HasZeroPointerIndex = C->isZero();
-
+
// Transform: GEP (bitcast [10 x i8]* X to [0 x i8]*), i32 0, ...
// into : GEP [10 x i8]* X, i32 0, ...
//
// Likewise, transform: GEP (bitcast i8* X to [0 x i8]*), i32 0, ...
// into : GEP i8* X, ...
- //
+ //
// This occurs when the program declares an array extern like "int X[];"
if (HasZeroPointerIndex) {
const PointerType *CPTy = cast<PointerType>(PtrOp->getType());
@@ -976,7 +975,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
}
}
}
-
+
/// See if we can simplify:
/// X = bitcast A* to B*
/// Y = gep X, <...constant indices...>
@@ -984,12 +983,14 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
/// analysis of unions. If "A" is also a bitcast, wait for A/X to be merged.
if (BitCastInst *BCI = dyn_cast<BitCastInst>(PtrOp)) {
if (TD &&
- !isa<BitCastInst>(BCI->getOperand(0)) && GEP.hasAllConstantIndices()) {
+ !isa<BitCastInst>(BCI->getOperand(0)) && GEP.hasAllConstantIndices() &&
+ StrippedPtrTy->getAddressSpace() == GEP.getPointerAddressSpace()) {
+
// Determine how much the GEP moves the pointer. We are guaranteed to get
// a constant back from EmitGEPOffset.
ConstantInt *OffsetV = cast<ConstantInt>(EmitGEPOffset(&GEP));
int64_t Offset = OffsetV->getSExtValue();
-
+
// If this GEP instruction doesn't move the pointer, just replace the GEP
// with a bitcast of the real input to the dest type.
if (Offset == 0) {
@@ -1635,7 +1636,6 @@ bool InstCombiner::DoOneIteration(Function &F, unsigned Iteration) {
bool InstCombiner::runOnFunction(Function &F) {
- MustPreserveLCSSA = mustPreserveAnalysisID(LCSSAID);
TD = getAnalysisIfAvailable<TargetData>();
@@ -1648,6 +1648,10 @@ bool InstCombiner::runOnFunction(Function &F) {
bool EverMadeChange = false;
+ // Lower dbg.declare intrinsics otherwise their value may be clobbered
+ // by instcombiner.
+ EverMadeChange = LowerDbgDeclare(F);
+
// Iterate while there is work to do.
unsigned Iteration = 0;
while (DoOneIteration(F, Iteration++))
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