Don't do FoldCmpLoadFromIndexedGlobal for non inbounds GEPs

This path wasn't tested before without a datalayout,
so add some more tests and re-run with and without one.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188507 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Matt Arsenault
2013-08-15 23:11:07 +00:00
parent c34540aa86
commit a630cb032c
3 changed files with 303 additions and 86 deletions

View File

@@ -226,8 +226,8 @@ static void ComputeUnsignedMinMaxValuesFromKnownBits(const APInt &KnownZero,
Instruction *InstCombiner::
FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
CmpInst &ICI, ConstantInt *AndCst) {
// We need TD information to know the pointer size unless this is inbounds.
if (!GEP->isInBounds() && TD == 0) return 0;
if (!GEP->isInBounds())
return 0;
Constant *Init = GV->getInitializer();
if (!isa<ConstantArray>(Init) && !isa<ConstantDataArray>(Init))
@@ -390,13 +390,6 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
// order the state machines in complexity of the generated code.
Value *Idx = GEP->getOperand(2);
// If the index is larger than the pointer size of the target, truncate the
// index down like the GEP would do implicitly. We don't have to do this for
// an inbounds GEP because the index can't be out of range.
if (!GEP->isInBounds() &&
Idx->getType()->getPrimitiveSizeInBits() > TD->getPointerSizeInBits())
Idx = Builder->CreateTrunc(Idx, TD->getIntPtrType(Idx->getContext()));
// If the comparison is only true for one or two elements, emit direct
// comparisons.
if (SecondTrueElement != Overdefined) {