[InstCombine] Do not RAUW a constant GEP

canRewriteGEPAsOffset expects to process instructions, not constants.

This fixes PR30342.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281650 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
David Majnemer 2016-09-15 20:10:09 +00:00
parent a5437a6d55
commit 26eccc1ec7
2 changed files with 21 additions and 1 deletions

View File

@ -625,7 +625,7 @@ static bool canRewriteGEPAsOffset(Value *Start, Value *Base,
}
if (!isa<IntToPtrInst>(V) && !isa<PtrToIntInst>(V) &&
!isa<GEPOperator>(V) && !isa<PHINode>(V))
!isa<GetElementPtrInst>(V) && !isa<PHINode>(V))
// We've found some value that we can't explore which is different from
// the base. Therefore we can't do this transformation.
return false;

View File

@ -167,4 +167,24 @@ lpad:
; CHECK: ret i32* %[[PTR]]
}
@pr30402 = constant i64 3
define i1 @test7() {
entry:
br label %bb7
bb7: ; preds = %bb10, %entry-block
%phi = phi i64* [ @pr30402, %entry ], [ getelementptr inbounds (i64, i64* @pr30402, i32 1), %bb7 ]
%cmp = icmp eq i64* %phi, getelementptr inbounds (i64, i64* @pr30402, i32 1)
br i1 %cmp, label %bb10, label %bb7
bb10:
ret i1 %cmp
}
; CHECK-LABEL: @test7(
; CHECK: %[[phi:.*]] = phi i64* [ @pr30402, %entry ], [ getelementptr inbounds (i64, i64* @pr30402, i32 1), %bb7 ]
; CHECK: %[[cmp:.*]] = icmp eq i64* %[[phi]], getelementptr inbounds (i64, i64* @pr30402, i32 1)
; CHECK: ret i1 %[[cmp]]
declare i32 @__gxx_personality_v0(...)