Make sure we don't return bits outside the mask in ComputeMaskedBits. PR12189.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152066 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eli Friedman 2012-03-05 23:09:40 +00:00
parent c3384c93c0
commit 049d08f5c9
2 changed files with 24 additions and 2 deletions

View File

@ -691,8 +691,8 @@ void llvm::ComputeMaskedBits(Value *V, const APInt &Mask,
if (P->hasConstantValue() == P)
break;
KnownZero = APInt::getAllOnesValue(BitWidth);
KnownOne = APInt::getAllOnesValue(BitWidth);
KnownZero = Mask;
KnownOne = Mask;
for (unsigned i = 0, e = P->getNumIncomingValues(); i != e; ++i) {
// Skip direct self references.
if (P->getIncomingValue(i) == P) continue;

View File

@ -0,0 +1,22 @@
; RUN: opt < %s -instsimplify -S | FileCheck %s
; PR12189
define i1 @test1(i32 %x) {
; CHECK: @test1
br i1 true, label %a, label %b
a:
%aa = or i32 %x, 10
br label %c
b:
%bb = or i32 %x, 10
br label %c
c:
%cc = phi i32 [ %bb, %b ], [%aa, %a ]
%d = urem i32 %cc, 2
%e = icmp eq i32 %d, 0
ret i1 %e
; CHECK: ret i1 %e
}