From f1ec34bdfd0bb3e276dd9639c7e46bef6a8b09ea Mon Sep 17 00:00:00 2001
From: Shuxin Yang <shuxin.llvm@gmail.com>
Date: Tue, 12 Nov 2013 08:33:03 +0000
Subject: [PATCH] Correct a glitch in r194424 which may invalidate iterator.

llvm-svn: 194457
---
 llvm/lib/Transforms/Scalar/GVN.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Transforms/Scalar/GVN.cpp b/llvm/lib/Transforms/Scalar/GVN.cpp
index d353765b42ae..6af269dfed32 100644
--- a/llvm/lib/Transforms/Scalar/GVN.cpp
+++ b/llvm/lib/Transforms/Scalar/GVN.cpp
@@ -2730,7 +2730,9 @@ void GVN::addDeadBlock(BasicBlock *BB) {
     if (DeadBlocks.count(B))
       continue;
 
-    for (pred_iterator PI = pred_begin(B), PE = pred_end(B); PI != PE; PI++) {
+    SmallVector<BasicBlock *, 4> Preds(pred_begin(B), pred_end(B));
+    for (SmallVectorImpl<BasicBlock *>::iterator PI = Preds.begin(),
+           PE = Preds.end(); PI != PE; PI++) {
       BasicBlock *P = *PI;
 
       if (!DeadBlocks.count(P))