From cdb51c9ac4313a9cd2a5448d8916b23236d839c7 Mon Sep 17 00:00:00 2001
From: Owen Anderson <resistor@mac.com>
Date: Mon, 11 Jun 2007 16:25:17 +0000
Subject: [PATCH] Handle functions with multiple exit blocks properly.

llvm-svn: 37539
---
 lib/Transforms/Scalar/GVNPRE.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/Transforms/Scalar/GVNPRE.cpp b/lib/Transforms/Scalar/GVNPRE.cpp
index 6a36ea3d010..c43603e6ddc 100644
--- a/lib/Transforms/Scalar/GVNPRE.cpp
+++ b/lib/Transforms/Scalar/GVNPRE.cpp
@@ -526,6 +526,9 @@ bool GVNPRE::runOnFunction(Function &F) {
          df_begin(PDT.getRootNode()), E = df_end(PDT.getRootNode());
          PDI != E; ++PDI) {
       BasicBlock* BB = PDI->getBlock();
+      if (BB == 0)
+        continue;
+      
       DOUT << "Block: " << BB->getName() << "\n";
       DOUT << "TMP_GEN: ";
       dump(generatedTemporaries[BB]);
@@ -635,6 +638,9 @@ bool GVNPRE::runOnFunction(Function &F) {
          E = df_end(DT.getRootNode()); DI != E; ++DI) {
       BasicBlock* BB = DI->getBlock();
       
+      if (BB == 0)
+        continue;
+      
       std::set<Value*, ExprLT>& new_set = new_sets[BB];
       std::set<Value*, ExprLT>& availOut = availableOut[BB];
       std::set<Value*, ExprLT>& anticIn = anticipatedIn[BB];