commit 56d2482a7d45a947b5bdf07b80bb23ceb78173f8
author Nick Lewycky <nicholas@mxc.ca> Thu Sep 20 00:48:36 2007 +0000
committer Nick Lewycky <nicholas@mxc.ca> Thu Sep 20 00:48:36 2007 +0000
tree dc55eb3066f65c3209bd917fd521cda7378a2fbe
parent cd497f4be825a3389ab7b338c07993782afd69ff

Fix optimization. %x = sub %x, %y does not imply that %y is zero.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42157 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/PredicateSimplifier.cpp

diff --git a/lib/Transforms/Scalar/PredicateSimplifier.cpp b/lib/Transforms/Scalar/PredicateSimplifier.cpp
index 8b4ed73..3723bcb 100644
--- a/lib/Transforms/Scalar/PredicateSimplifier.cpp
+++ b/lib/Transforms/Scalar/PredicateSimplifier.cpp
@@ -2001,7 +2001,7 @@
               if (!isRelatedBy(Known, Zero, ICmpInst::ICMP_NE)) break;
               // otherwise, fall-through.
             case Instruction::Sub:
-              if (Unknown == Op1) break;
+              if (Unknown == Op0) break;
               // otherwise, fall-through.
             case Instruction::Xor:
             case Instruction::Add: