From: Duncan Sands <baldrick@free.fr>
Date: Sun, 5 Feb 2012 19:43:37 +0000 (+0000)
Subject: Neaten up this method.  Check that if there is only one
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=c4fd448712a70a414bcf05d74f77416407ae42c2;p=oota-llvm.git

Neaten up this method.  Check that if there is only one
predecessor then it's Src.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149843 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index f6d6b90b99a..654125342a4 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -1999,10 +1999,10 @@ static bool isOnlyReachableViaThisEdge(BasicBlock *Src, BasicBlock *Dst,
   // only reachable from Src, in practice it is pointless since at the time
   // GVN runs all such loops have preheaders, which means that Dst will have
   // been changed to have only one predecessor, namely Src.
-  pred_iterator PI = pred_begin(Dst), PE = pred_end(Dst);
-  assert(PI != PE && "No edge between these basic blocks!");
+  BasicBlock *Pred = Dst->getSinglePredecessor();
+  assert((!Pred || Pred == Src) && "No edge between these basic blocks!");
   (void)Src;
-  return PE == ++PI;
+  return Pred != 0;
 }
 
 /// processInstruction - When calculating availability, handle an instruction