From 03d8ed439f55b692634f9c71721ecfabbe347c4d Mon Sep 17 00:00:00 2001
From: Anders Carlsson <andersca@mac.com>
Date: Fri, 13 Nov 2009 04:34:45 +0000
Subject: [PATCH] Fix two bugs with temporaries:

1. For

A f() {
	return A();
}

we were incorrectly calling the A destructor on the returned object.

2. For

void f(A);
void g() {
	A a;
	f(a);
}

we were incorrectly not calling the copy constructor.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@87082 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGCXX.cpp           |  9 +++++++--
 lib/Sema/SemaExpr.cpp           |  2 ++
 test/CodeGenCXX/temporaries.cpp | 23 +++++++++++++++++++++++
 3 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
index 3e9951f83b..9651c1ae83 100644
--- a/lib/CodeGen/CGCXX.cpp
+++ b/lib/CodeGen/CGCXX.cpp
@@ -671,8 +671,13 @@ CodeGenFunction::EmitCXXConstructExpr(llvm::Value *Dest,
   // Code gen optimization to eliminate copy constructor and return
   // its first argument instead.
   if (getContext().getLangOptions().ElideConstructors && E->isElidable()) {
-    CXXConstructExpr::const_arg_iterator i = E->arg_begin();
-    EmitAggExpr((*i), Dest, false);
+    const Expr *Arg = E->getArg(0);
+    
+    if (const CXXBindTemporaryExpr *BindExpr = 
+          dyn_cast<CXXBindTemporaryExpr>(Arg))
+      Arg = BindExpr->getSubExpr();
+
+    EmitAggExpr(Arg, Dest, false);
     return;
   }
   if (Array) {
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 1288f56675..3663f0923d 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -2652,6 +2652,8 @@ Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
       // Pass the argument.
       if (PerformCopyInitialization(Arg, ProtoArgType, "passing"))
         return true;
+      
+      Arg = MaybeBindToTemporary(Arg).takeAs<Expr>();
     } else {
       ParmVarDecl *Param = FDecl->getParamDecl(i);
 
diff --git a/test/CodeGenCXX/temporaries.cpp b/test/CodeGenCXX/temporaries.cpp
index 87ca9ca7d4..4f65e462d4 100644
--- a/test/CodeGenCXX/temporaries.cpp
+++ b/test/CodeGenCXX/temporaries.cpp
@@ -162,6 +162,29 @@ C::C()
   
   // CHECK: call void @_ZN6PR50771BD1Ev
 }
+}
+
+A f8() {
+  // CHECK: call void @_ZN1AC1Ev
+  // CHECK-NOT: call void @_ZN1AD1Ev
+  return A();
+  // CHECK: ret void
+}
 
+struct H {
+  H();
+  ~H();
+  H(const H&);
+};
 
+void f9(H h) {
+  // CHECK: call void @_ZN1HC1Ev
+  // CHECK: call void @_Z2f91H
+  // CHECK: call void @_ZN1HD1Ev
+  f9(H());
+  
+  // CHECK: call void @_ZN1HC1ERKS_
+  // CHECK: call void @_Z2f91H
+  // CHECK: call void @_ZN1HD1Ev
+  f9(h);
 }
-- 
2.50.1