SROA: The alloca type isn't a candidate promotion type for vectors

The alloca's type is irrelevant, only those types which are used in a
load or store of the exact size of the slice should be considered.

This manifested as an assertion failure when we compared the various
types: we had a size mismatch.

This fixes PR21480.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222499 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
David Majnemer 2014-11-21 02:34:55 +00:00
parent 57ec3b5488
commit 9970214474
3 changed files with 28 additions and 3 deletions

View File

@ -394,6 +394,13 @@ static BinaryOperator *LowerNegateToMultiply(Instruction *Neg) {
BinaryOperator *Res = CreateMul(Neg->getOperand(1), NegOne, "", Neg, Neg);
Neg->setOperand(1, Constant::getNullValue(Ty)); // Drop use of op.
Res->takeName(Neg);
if (Ty->isIntegerTy()) {
bool NSW = cast<BinaryOperator>(Neg)->hasNoSignedWrap();
bool NUW = cast<BinaryOperator>(Neg)->hasNoUnsignedWrap();
if (NSW || NUW)
Res->setHasNoSignedWrap(true);
Res->setHasNoUnsignedWrap(NUW);
}
Neg->replaceAllUsesWith(Res);
Res->setDebugLoc(Neg->getDebugLoc());
return Res;

View File

@ -1691,7 +1691,7 @@ isVectorPromotionViableForSlice(const DataLayout &DL, uint64_t SliceBeginOffset,
/// don't want to do the rewrites unless we are confident that the result will
/// be promotable, so we have an early test here.
static VectorType *
isVectorPromotionViable(const DataLayout &DL, Type *AllocaTy,
isVectorPromotionViable(const DataLayout &DL,
uint64_t SliceBeginOffset, uint64_t SliceEndOffset,
AllocaSlices::const_range Slices,
ArrayRef<AllocaSlices::iterator> SplitUses) {
@ -1709,7 +1709,6 @@ isVectorPromotionViable(const DataLayout &DL, Type *AllocaTy,
HaveCommonEltTy = false;
}
};
CheckCandidateType(AllocaTy);
// Consider any loads or stores that are the exact size of the slice.
for (const auto &S : Slices)
if (S.beginOffset() == SliceBeginOffset &&
@ -3213,7 +3212,7 @@ bool SROA::rewritePartition(AllocaInst &AI, AllocaSlices &AS,
VectorType *VecTy =
IsIntegerPromotable
? nullptr
: isVectorPromotionViable(*DL, SliceTy, BeginOffset, EndOffset,
: isVectorPromotionViable(*DL, BeginOffset, EndOffset,
AllocaSlices::const_range(B, E), SplitUses);
if (VecTy)
SliceTy = VecTy;

View File

@ -604,3 +604,22 @@ entry:
ret <2 x float> %result
; CHECK-NEXT: ret <2 x float> %[[V4]]
}
define <4 x float> @test12() {
; CHECK-LABEL: @test12(
%a = alloca <3 x i32>, align 16
; CHECK-NOT: alloca
%cast1 = bitcast <3 x i32>* %a to <4 x i32>*
store <4 x i32> undef, <4 x i32>* %cast1, align 16
; CHECK-NOT: store
%cast2 = bitcast <3 x i32>* %a to <3 x float>*
%cast3 = bitcast <3 x float>* %cast2 to <4 x float>*
%vec = load <4 x float>* %cast3
; CHECK-NOT: load
; CHECK: %[[ret:.*]] = bitcast <4 x i32> undef to <4 x float>
; CHECK-NEXT: ret <4 x float> %[[ret]]
ret <4 x float> %vec
}