Run the pre-register allocation tail duplication pass by default. Remove

the -pre-regalloc-taildup command-line option, and add a new
-disable-early-taildup option.

llvm-svn: 93597

1 files changed, 3 insertions, 5 deletions

diff --git a/llvm/lib/CodeGen/LLVMTargetMachine.cpp b/llvm/lib/CodeGen/LLVMTargetMachine.cpp
index 758c81dc593..837e1848aa5 100644
--- a/llvm/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/llvm/lib/CodeGen/LLVMTargetMachine.cpp
@@ -39,6 +39,8 @@ static cl::opt<bool> DisableBranchFold("disable-branch-fold", cl::Hidden,
     cl::desc("Disable branch folding"));
 static cl::opt<bool> DisableTailDuplicate("disable-tail-duplicate", cl::Hidden,
     cl::desc("Disable tail duplication"));
+static cl::opt<bool> DisableEarlyTailDup("disable-early-taildup", cl::Hidden,
+    cl::desc("Disable pre-register allocation tail duplication"));
 static cl::opt<bool> DisableCodePlace("disable-code-place", cl::Hidden,
     cl::desc("Disable code placement"));
 static cl::opt<bool> DisableSSC("disable-ssc", cl::Hidden,
@@ -77,9 +79,6 @@ EnableFastISelOption("fast-isel", cl::Hidden,
 static cl::opt<bool> EnableSplitGEPGVN("split-gep-gvn", cl::Hidden,
     cl::desc("Split GEPs and run no-load GVN"));
 
-static cl::opt<bool> PreAllocTailDup("pre-regalloc-taildup", cl::Hidden,
-    cl::desc("Pre-register allocation tail duplication"));
-
 LLVMTargetMachine::LLVMTargetMachine(const Target &T,
                                      const std::string &TargetTriple)
   : TargetMachine(T) {
@@ -351,8 +350,7 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
   }
 
   // Pre-ra tail duplication.
-  if (OptLevel != CodeGenOpt::None &&
-      !DisableTailDuplicate && PreAllocTailDup) {
+  if (OptLevel != CodeGenOpt::None && !DisableEarlyTailDup) {
     PM.add(createTailDuplicatePass(true));
     printAndVerify(PM, "After Pre-RegAlloc TailDuplicate",
                    /* allowDoubleDefs= */ true);