Vendor import of llvm release_31 branch r155985:

http://llvm.org/svn/llvm-project/llvm/branches/release_31@155985

2 files changed, 11 insertions, 2 deletions

diff --git a/lib/Transforms/IPO/Internalize.cpp b/lib/Transforms/IPO/Internalize.cpp
index cd29e7a..fb5869e 100644
--- a/lib/Transforms/IPO/Internalize.cpp
+++ b/lib/Transforms/IPO/Internalize.cpp
@@ -123,6 +123,8 @@ bool InternalizePass::runOnModule(Module &M) {
   bool Changed = false;
 
   // Never internalize functions which code-gen might insert.
+  // FIXME: We should probably add this (and the __stack_chk_guard) via some
+  // type of call-back in CodeGen.
   ExternalNames.insert("__stack_chk_fail");
 
   // Mark all functions not in the api as internal.
diff --git a/lib/Transforms/IPO/PassManagerBuilder.cpp b/lib/Transforms/IPO/PassManagerBuilder.cpp
index a1b0a45..43b4ab5 100644
--- a/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -35,6 +35,11 @@ using namespace llvm;
 static cl::opt<bool>
 RunVectorization("vectorize", cl::desc("Run vectorization passes"));
 
+static cl::opt<bool>
+UseGVNAfterVectorization("use-gvn-after-vectorization",
+  cl::init(false), cl::Hidden,
+  cl::desc("Run GVN instead of Early CSE after vectorization passes"));
+
 PassManagerBuilder::PassManagerBuilder() {
     OptLevel = 2;
     SizeLevel = 0;
@@ -182,8 +187,10 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
   if (Vectorize) {
     MPM.add(createBBVectorizePass());
     MPM.add(createInstructionCombiningPass());
-    if (OptLevel > 1)
-      MPM.add(createGVNPass());                 // Remove redundancies
+    if (OptLevel > 1 && UseGVNAfterVectorization)
+      MPM.add(createGVNPass());                   // Remove redundancies
+    else
+      MPM.add(createEarlyCSEPass());              // Catch trivial redundancies
   }
 
   MPM.add(createAggressiveDCEPass());         // Delete dead instructions