Reapply r180982 with repaired logic and an additional testcase.

Un-break the gdb buildbot.
- Use the debug location of the return expression for the cleanup code
  if the return expression is trivially evaluatable, regardless of the
  number of stop points in the function.
- Ensure that any EH code in the cleanup still gets the line number of
  the closing } of the lexical scope.
- Added a testcase with EH in the cleanup.

rdar://problem/13442648

llvm-svn: 181056

clang/lib/CodeGen/CodeGenFunction.cpp

@@ -44,7 +44,7 @@ CodeGenFunction::CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext)
     DebugInfo(0), DisableDebugInfo(false), CalleeWithThisReturn(0),
     DidCallStackSave(false),
     IndirectBranch(0), SwitchInsn(0), CaseRangeBlock(0), UnreachableBlock(0),
-    NumStopPoints(0), NumSimpleReturnExprs(0),
+    NumReturnExprs(0), NumSimpleReturnExprs(0),
     CXXABIThisDecl(0), CXXABIThisValue(0), CXXThisValue(0),
     CXXDefaultInitExprThis(0),
     CXXStructorImplicitParamDecl(0), CXXStructorImplicitParamValue(0),
@@ -188,14 +188,16 @@ void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
   assert(BreakContinueStack.empty() &&
          "mismatched push/pop in break/continue stack!");
 
-  // If the function contains only a single, simple return statement,
-  // the cleanup code may become the first breakpoint in the
-  // function. To be safe set the debug location for it to the
-  // location of the return statement.  Otherwise point it to end of
-  // the function's lexical scope.
+  bool OnlySimpleReturnStmts = NumSimpleReturnExprs > 0
+    && NumSimpleReturnExprs == NumReturnExprs;
+  // If the function contains only a simple return statement, the
+  // cleanup code may become the first breakpoint in the function. To
+  // be safe, set the debug location for it to the location of the
+  // return statement.  Otherwise point it to end of the function's
+  // lexical scope.
   if (CGDebugInfo *DI = getDebugInfo()) {
-    if (NumSimpleReturnExprs == 1 && NumStopPoints == 1)
-      DI->EmitLocation(Builder, FirstStopPoint);
+    if (OnlySimpleReturnStmts)
+       DI->EmitLocation(Builder, LastStopPoint);
     else
       DI->EmitLocation(Builder, EndLoc);
   }
@@ -206,14 +208,14 @@ void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
   // edges will be *really* confused.
   bool EmitRetDbgLoc = true;
   if (EHStack.stable_begin() != PrologueCleanupDepth) {
-    PopCleanupBlocks(PrologueCleanupDepth);
+    PopCleanupBlocks(PrologueCleanupDepth, EndLoc);
 
     // Make sure the line table doesn't jump back into the body for
     // the ret after it's been at EndLoc.
     EmitRetDbgLoc = false;
 
     if (CGDebugInfo *DI = getDebugInfo())
-      if (NumSimpleReturnExprs == 1 && NumStopPoints == 1)
+      if (OnlySimpleReturnStmts)
         DI->EmitLocation(Builder, EndLoc);
   }