PR13046: we can't replace usage of SUB with CMP in the lowering phase.

It will cause assertion failure later on.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158160 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 57f61ab38fce4e62a20645ddad228d6cca4aeb39..7b2f13b75d738791ca10886c14f9a23579c6f4aa 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -8306,7 +8306,8 @@ SDValue X86TargetLowering::EmitTest(SDValue Op, unsigned X86CC,
   if (Opcode == X86ISD::CMP) {
     SDValue New = DAG.getNode(Opcode, dl, MVT::i32, Op.getOperand(0),
                               Op.getOperand(1));
-    DAG.ReplaceAllUsesWith(Op, New);
+    // We can't replace usage of SUB with CMP.
+    // The SUB node will be removed later because there is no use of it.
     return SDValue(New.getNode(), 0);
   }