From: Dale Johannesen <dalej@apple.com>
Date: Fri, 18 Apr 2008 21:38:31 +0000 (+0000)
Subject: Fix a scalar evolution bug.  Reversing everything
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=cf363181c1b98c0982010cf5714e31b7277bdd2a;p=oota-llvm.git

Fix a scalar evolution bug.  Reversing everything
does not work because of 0; 2>0 but -2U is also >0.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49928 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 4b4b97e2862..0508bb76c1e 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -1980,8 +1980,7 @@ SCEVHandle ScalarEvolutionsImpl::ComputeIterationCount(const Loop *L) {
     break;
   }
   case ICmpInst::ICMP_UGT: {
-    SCEVHandle TC = HowManyLessThans(SE.getNegativeSCEV(LHS),
-                                     SE.getNegativeSCEV(RHS), L, false);
+    SCEVHandle TC = HowFarToZero(SE.getMinusSCEV(LHS, RHS), L);
     if (!isa<SCEVCouldNotCompute>(TC)) return TC;
     break;
   }