From 253410c6e64c86e5b2906345ed21f52672c76272 Mon Sep 17 00:00:00 2001
From: Anton Korobeynikov <asl@math.spbu.ru>
Date: Sun, 22 Jan 2012 14:08:34 +0000
Subject: [PATCH] Add an option to disable buggy copy propagation pass

llvm-svn: 148662
---
 lib/CodeGen/LLVMTargetMachine.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp
index a04f3ed3de0..3a9f0f013b1 100644
--- a/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/lib/CodeGen/LLVMTargetMachine.cpp
@@ -72,6 +72,8 @@ static cl::opt<bool> DisableLSR("disable-lsr", cl::Hidden,
     cl::desc("Disable Loop Strength Reduction Pass"));
 static cl::opt<bool> DisableCGP("disable-cgp", cl::Hidden,
     cl::desc("Disable Codegen Prepare"));
+static cl::opt<bool> DisableCopyProp("disable-copyprop", cl::Hidden,
+    cl::desc("Disable Copy Propagation pass"));
 static cl::opt<bool> PrintLSR("print-lsr-output", cl::Hidden,
     cl::desc("Print LLVM IR produced by the loop-reduce pass"));
 static cl::opt<bool> PrintISelInput("print-isel-input", cl::Hidden,
@@ -463,7 +465,7 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
   }
 
   // Copy propagation.
-  if (getOptLevel() != CodeGenOpt::None) {
+  if (getOptLevel() != CodeGenOpt::None && !DisableCopyProp) {
     PM.add(createMachineCopyPropagationPass());
     printNoVerify(PM, "After copy propagation pass");
   }