Fix the last crasher I've gotten a reproduction for in SROA. This one

from the dragonegg build bots when we turned on the full version of the
pass. Included a much reduced test case for this pesky bug, despite
bugpoint's uncooperative behavior.

Also, I audited all the similar code I could find and didn't spot any
other cases where this mistake cropped up.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164178 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chandler Carruth 2012-09-18 22:37:19 +00:00
parent a177a51108
commit 38f35fd3b7
2 changed files with 22 additions and 0 deletions

View File

@ -1487,6 +1487,8 @@ static Value *getNaturalGEPWithOffset(IRBuilder<> &IRB, const TargetData &TD,
return 0;
Type *ElementTy = Ty->getElementType();
if (!ElementTy->isSized())
return 0; // We can't GEP through an unsized element.
APInt ElementSize(Offset.getBitWidth(), TD.getTypeAllocSize(ElementTy));
if (ElementSize == 0)
return 0; // Zero-length arrays can't help us build a natural GEP.

View File

@ -754,3 +754,23 @@ entry:
ret void
}
%opaque = type opaque
define i32 @test19(%opaque* %x) {
; This input will cause us to try to compute a natural GEP when rewriting
; pointers in such a way that we try to GEP through the opaque type. Previously,
; a check for an unsized type was missing and this crashed. Ensure it behaves
; reasonably now.
; CHECK: @test19
; CHECK-NOT: alloca
; CHECK: ret i32 undef
entry:
%a = alloca { i64, i8* }
%cast1 = bitcast %opaque* %x to i8*
%cast2 = bitcast { i64, i8* }* %a to i8*
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %cast2, i8* %cast1, i32 16, i32 1, i1 false)
%gep = getelementptr inbounds { i64, i8* }* %a, i32 0, i32 0
%val = load i64* %gep
ret i32 undef
}