diff options
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 8 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/2012-3-15-or-xor-constant.ll | 12 |
2 files changed, 19 insertions, 1 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index cc8f5bf43e..1165660f40 100644 --- a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -1929,8 +1929,11 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { } // Canonicalize xor to the RHS. - if (match(Op0, m_Xor(m_Value(), m_Value()))) + bool SwappedForXor = false; + if (match(Op0, m_Xor(m_Value(), m_Value()))) { std::swap(Op0, Op1); + SwappedForXor = true; + } // A | ( A ^ B) -> A | B // A | (~A ^ B) -> A | ~B @@ -1961,6 +1964,9 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { return BinaryOperator::CreateOr(Not, Op0); } + if (SwappedForXor) + std::swap(Op0, Op1); + if (ICmpInst *RHS = dyn_cast<ICmpInst>(I.getOperand(1))) if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0))) if (Value *Res = FoldOrOfICmps(LHS, RHS)) diff --git a/test/Transforms/InstCombine/2012-3-15-or-xor-constant.ll b/test/Transforms/InstCombine/2012-3-15-or-xor-constant.ll new file mode 100644 index 0000000000..c1602da4c8 --- /dev/null +++ b/test/Transforms/InstCombine/2012-3-15-or-xor-constant.ll @@ -0,0 +1,12 @@ +; RUN: opt < %s -instcombine -S | FileCheck %s +; PR12234 + +@g = extern_weak global i32 +define i32 @function(i32 %x) nounwind { +entry: + %xor = xor i32 %x, 1 + store volatile i32 %xor, i32* inttoptr (i64 1 to i32*), align 4 + %or4 = or i32 or (i32 zext (i1 icmp eq (i32* @g, i32* null) to i32), i32 1), %xor + ret i32 %or4 +} +; CHECK: define i32 @function |