From: Eli Friedman <eli.friedman@gmail.com>
Date: Thu, 26 Nov 2009 07:45:48 +0000 (+0000)
Subject: Shortcut explicit calls to a trivial copy assignment operator.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ae32e2459edad5cd13384c70a726d7ecb78c9b5c;p=clang

Shortcut explicit calls to a trivial copy assignment operator.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89944 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
index 3b97fcb117..a0b02d53b6 100644
--- a/lib/CodeGen/CGCXX.cpp
+++ b/lib/CodeGen/CGCXX.cpp
@@ -270,6 +270,14 @@ RValue CodeGenFunction::EmitCXXMemberCallExpr(const CXXMemberCallExpr *CE) {
     This = BaseLV.getAddress();
   }
 
+  if (MD->isCopyAssignment() && MD->isTrivial()) {
+    // We don't like to generate the trivial copy assignment operator when
+    // it isn't necessary; just produce the proper effect here.
+    llvm::Value *RHS = EmitLValue(*CE->arg_begin()).getAddress();
+    EmitAggregateCopy(This, RHS, CE->getType());
+    return RValue::get(This);
+  }
+
   // C++ [class.virtual]p12:
   //   Explicit qualification with the scope operator (5.1) suppresses the
   //   virtual call mechanism.