Implement mcount profiling, enabled via -pg.

llvm-svn: 125282

2 files changed, 15 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 66114c87a45..364f2697e60 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -210,6 +210,15 @@ void CodeGenFunction::EmitFunctionInstrumentation(const char *Fn) {
                       CallSite);
 }
 
+void CodeGenFunction::EmitMCountInstrumentation() {
+  llvm::FunctionType *FTy =
+    llvm::FunctionType::get(llvm::Type::getVoidTy(getLLVMContext()), false);
+
+  llvm::Constant *MCountFn = CGM.CreateRuntimeFunction(FTy,
+                                                       Target.getMCountName());
+  Builder.CreateCall(MCountFn);
+}
+
 void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
                                     llvm::Function *Fn,
                                     const FunctionArgList &Args,
@@ -260,6 +269,9 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
 
   EmitFunctionInstrumentation("__cyg_profile_func_enter");
 
+  if (CGM.getCodeGenOpts().InstrumentForProfiling)
+    EmitMCountInstrumentation();
+
   // FIXME: Leaked.
   // CC info is ignored, hopefully?
   CurFnInfo = &CGM.getTypes().getFunctionInfo(FnRetTy, Args,
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 19fbf5ca989..1fe1c3fda9d 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1087,6 +1087,9 @@ public:
   /// function instrumentation is enabled.
   void EmitFunctionInstrumentation(const char *Fn);
 
+  /// EmitMCountInstrumentation - Emit call to .mcount.
+  void EmitMCountInstrumentation();
+
   /// EmitFunctionProlog - Emit the target specific LLVM code to load the
   /// arguments for the given function. This is also responsible for naming the
   /// LLVM function arguments.