From: Sebastian Pop <spop@codeaurora.org>
Date: Thu, 29 May 2014 19:44:09 +0000 (+0000)
Subject: implement missing SCEVDivision case
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=20daf3276d1a32701ed7b5da9b6c3af49af5f7e1;p=platform%2Fupstream%2Fllvm.git

implement missing SCEVDivision case

without this case we would end on an infinite recursion: the remainder is zero,
so Numerator - Remainder is equal to Numerator and so we would recursively ask
for the division of Numerator by Denominator.

llvm-svn: 209838
---

diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 935d415..bc9f45b 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -7216,6 +7216,15 @@ public:
         cast<SCEVConstant>(Zero)->getValue();
     Remainder = SCEVParameterRewriter::rewrite(Numerator, SE, RewriteMap, true);
 
+    if (Remainder->isZero()) {
+      // The Quotient is obtained by replacing Denominator by 1 in Numerator.
+      RewriteMap[cast<SCEVUnknown>(Denominator)->getValue()] =
+          cast<SCEVConstant>(One)->getValue();
+      Quotient =
+          SCEVParameterRewriter::rewrite(Numerator, SE, RewriteMap, true);
+      return;
+    }
+
     // Quotient is (Numerator - Remainder) divided by Denominator.
     const SCEV *Q, *R;
     const SCEV *Diff = SE.getMinusSCEV(Numerator, Remainder);