[PATCH] [-cxx-abi microsoft] Mangle user defined entry points properly

[David Majnemer]

Hi timurrrr, pcc, rnk, whunt,

Functions named "main", "wmain", "WinMain", "wWinMain", and "DllMain"
are never mangled regardless of linkage, even when compiling for kernel
mode.
Depends on D1655

http://llvm-reviews.chandlerc.com/D1670

Files:
  lib/AST/MicrosoftMangle.cpp
  test/CodeGenCXX/mangle-ms.cpp

Index: lib/AST/MicrosoftMangle.cpp
===================================================================
--- lib/AST/MicrosoftMangle.cpp
+++ lib/AST/MicrosoftMangle.cpp
@@ -24,6 +24,7 @@
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/TargetInfo.h"
 #include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringSwitch.h"
 
 using namespace clang;
 
@@ -70,6 +71,22 @@
   return fn;
 }
 
+// Microsoft Visual C++ will never mangle some "standard" entry points
+// regardless of visibility or freestanding-ness.
+static bool isUserDefinedEntryPoint(const FunctionDecl *FD) {
+  if (!FD->getIdentifier())
+    return false;
+
+  return llvm::StringSwitch<bool>(FD->getName())
+      .Cases("main",     // An ANSI console app
+             "wmain",    // A Unicode console App
+             "WinMain",  // An ANSI GUI app
+             "wWinMain", // A Unicode GUI app
+             "DllMain",  // A DLL
+             true)
+      .Default(false);
+}
+
 /// MicrosoftCXXNameMangler - Manage the mangling of a single name for the
 /// Microsoft Visual C++ ABI.
 class MicrosoftCXXNameMangler {
@@ -230,8 +247,7 @@
     if (FD->hasAttr<OverloadableAttr>())
       return true;
 
-    // "main" is not mangled.
-    if (FD->isMain())
+    if (isUserDefinedEntryPoint(FD))
       return false;
 
     // C++ functions and those whose names are not a simple identifier need
Index: test/CodeGenCXX/mangle-ms.cpp
===================================================================
--- test/CodeGenCXX/mangle-ms.cpp
+++ test/CodeGenCXX/mangle-ms.cpp
@@ -255,3 +255,28 @@
 void call_extern_c_func() {
   extern_c_func();
 }
+
+int main() {
+}
+// CHECK-DAG: @main
+// X64-DAG:   @main
+
+int wmain() {
+}
+// CHECK-DAG: @wmain
+// X64-DAG:   @wmain
+
+int WinMain() {
+}
+// CHECK-DAG: @WinMain
+// X64-DAG:   @WinMain
+
+int wWinMain() {
+}
+// CHECK-DAG: @wWinMain
+// X64-DAG:   @wWinMain
+
+int DllMain() {
+}
+// CHECK-DAG: @DllMain
+// X64-DAG:   @DllMain
-------------- next part --------------
A non-text attachment was scrubbed...
Name: D1670.1.patch
Type: text/x-patch
Size: 1963 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20130912/63791fdb/attachment.bin>