IRgen: Fix debug info regression in r106970; when we eliminate the return value

store make sure to move the debug metadata from the store (which is actual
'return' statement location) to the return instruction (which otherwise would
have the function end location as its debug info).
 - Tested by gdb test suite.

llvm-svn: 107322

1 files changed, 6 insertions, 5 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 24a64cfa443..29104424acb 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -975,7 +975,8 @@ void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI) {
     Builder.CreateRetVoid();
     return;
   }
-  
+
+  llvm::MDNode *RetDbgInfo = 0;
   llvm::Value *RV = 0;
   QualType RetTy = FI.getReturnType();
   const ABIArgInfo &RetAI = FI.getReturnInfo();
@@ -1009,6 +1010,7 @@ void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI) {
       RV = Builder.CreateLoad(ReturnValue);
     } else {
       // Get the stored value and nuke the now-dead store.
+      RetDbgInfo = SI->getDbgMetadata();
       RV = SI->getValueOperand();
       SI->eraseFromParent();
       
@@ -1031,10 +1033,9 @@ void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI) {
     assert(0 && "Invalid ABI kind for return argument");
   }
 
-  if (RV)
-    Builder.CreateRet(RV);
-  else
-    Builder.CreateRetVoid();
+  llvm::Instruction *Ret = RV ? Builder.CreateRet(RV) : Builder.CreateRetVoid();
+  if (RetDbgInfo)
+    Ret->setDbgMetadata(RetDbgInfo);
 }
 
 RValue CodeGenFunction::EmitDelegateCallArg(const VarDecl *Param) {