[NewGVN] Don't derive incorrect implications.

In the testcase attached,  we believe %tmp1 implies %tmp4.
where:
  br i1 %tmp1, label %bb2, label %bb7
  br i1 %tmp4, label %bb5, label %bb7

because Wwhile looking at PredicateInfo stuffs we end up calling
isImpliedTrueByMatchingCmp() with the arguments backwards.

Differential Revision:  https://reviews.llvm.org/D32718

llvm-svn: 301849

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/Transforms/Scalar/NewGVN.cpp b/llvm/lib/Transforms/Scalar/NewGVN.cpp
index 18d31f16a74..162d91beae7 100644
--- a/llvm/lib/Transforms/Scalar/NewGVN.cpp
+++ b/llvm/lib/Transforms/Scalar/NewGVN.cpp
@@ -1628,15 +1628,15 @@ const Expression *NewGVN::performSymbolicCmpEvaluation(Instruction *I) {
         if (PBranch->TrueEdge) {
           // If we know the previous predicate is true and we are in the true
           // edge then we may be implied true or false.
-          if (CmpInst::isImpliedTrueByMatchingCmp(OurPredicate,
-                                                  BranchPredicate)) {
+          if (CmpInst::isImpliedTrueByMatchingCmp(BranchPredicate,
+                                                  OurPredicate)) {
             addPredicateUsers(PI, I);
             return createConstantExpression(
                 ConstantInt::getTrue(CI->getType()));
           }
 
-          if (CmpInst::isImpliedFalseByMatchingCmp(OurPredicate,
-                                                   BranchPredicate)) {
+          if (CmpInst::isImpliedFalseByMatchingCmp(BranchPredicate,
+                                                   OurPredicate)) {
             addPredicateUsers(PI, I);
             return createConstantExpression(
                 ConstantInt::getFalse(CI->getType()));