When canonicalizing icmp operand order to put the loop invariant

operand on the left, the interesting operand is on the right. This
fixes a bug where LSR was failing to recognize ICmpZero uses,
which led it to be unable to reverse the induction variable in the
attached testcase.

Delete test/CodeGen/X86/stack-color-with-reg-2.ll, because its test
is extremely fragile and hard to meaningfully update.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104262 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/LoopStrengthReduce.cpp

@@ -1997,6 +1997,7 @@ void LSRInstance::CollectFixupsAndInitialFormulae() {
         if (NV == LF.OperandValToReplace) {
           CI->setOperand(1, CI->getOperand(0));
           CI->setOperand(0, NV);
+          NV = CI->getOperand(1);
           Changed = true;
         }