r204821 - -fms-extensions: Add __va_start builtin, which is used for x64

[Reid Kleckner]

Author: rnk
Date: Wed Mar 26 10:38:33 2014
New Revision: 204821

URL: http://llvm.org/viewvc/llvm-project?rev=204821&view=rev
Log:
-fms-extensions: Add __va_start builtin, which is used for x64

The main difference between __va_start and __builtin_va_start is that
the address of the va_list has already been taken, and the va_list is
always a char*.

__va_end and __va_arg are not needed.

Modified:
    cfe/trunk/include/clang/Basic/Builtins.def
    cfe/trunk/lib/CodeGen/CGBuiltin.cpp
    cfe/trunk/lib/Sema/SemaChecking.cpp
    cfe/trunk/test/Sema/MicrosoftExtensions.c

Modified: cfe/trunk/include/clang/Basic/Builtins.def
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Builtins.def?rev=204821&r1=204820&r2=204821&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/Builtins.def (original)
+++ cfe/trunk/include/clang/Basic/Builtins.def Wed Mar 26 10:38:33 2014
@@ -681,6 +681,7 @@ LANGBUILTIN(_alloca,      "v*z", "n", AL
 LANGBUILTIN(__assume,     "vb",  "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(__noop,       "v.",  "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(__debugbreak, "v",   "n", ALL_MS_LANGUAGES)
+LANGBUILTIN(__va_start,   "vc**.", "nt", ALL_MS_LANGUAGES)
 LANGBUILTIN(_InterlockedCompareExchange, "LiLiD*LiLi", "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(_InterlockedIncrement, "LiLiD*", "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(_InterlockedDecrement, "LiLiD*", "n", ALL_MS_LANGUAGES)

Modified: cfe/trunk/lib/CodeGen/CGBuiltin.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGBuiltin.cpp?rev=204821&r1=204820&r2=204821&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGBuiltin.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGBuiltin.cpp Wed Mar 26 10:38:33 2014
@@ -215,8 +215,11 @@ RValue CodeGenFunction::EmitBuiltinExpr(
     return RValue::get(CGM.EmitConstantExpr(E, E->getType(), 0));
   case Builtin::BI__builtin_stdarg_start:
   case Builtin::BI__builtin_va_start:
+  case Builtin::BI__va_start:
   case Builtin::BI__builtin_va_end: {
-    Value *ArgValue = EmitVAListRef(E->getArg(0));
+    Value *ArgValue = (BuiltinID == Builtin::BI__va_start)
+                          ? EmitScalarExpr(E->getArg(0))
+                          : EmitVAListRef(E->getArg(0));
     llvm::Type *DestType = Int8PtrTy;
     if (ArgValue->getType() != DestType)
       ArgValue = Builder.CreateBitCast(ArgValue, DestType,

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=204821&r1=204820&r2=204821&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Wed Mar 26 10:38:33 2014
@@ -142,6 +142,7 @@ Sema::CheckBuiltinFunctionCall(unsigned
     break;
   case Builtin::BI__builtin_stdarg_start:
   case Builtin::BI__builtin_va_start:
+  case Builtin::BI__va_start:
     if (SemaBuiltinVAStart(TheCall))
       return ExprError();
     break;

Modified: cfe/trunk/test/Sema/MicrosoftExtensions.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/MicrosoftExtensions.c?rev=204821&r1=204820&r2=204821&view=diff
==============================================================================
--- cfe/trunk/test/Sema/MicrosoftExtensions.c (original)
+++ cfe/trunk/test/Sema/MicrosoftExtensions.c Wed Mar 26 10:38:33 2014
@@ -131,3 +131,17 @@ int *(__ptr32 __sptr wrong9); // expecte
 
 typedef int *T;
 T __ptr32 wrong10; // expected-error {{'__ptr32' attribute only applies to pointer arguments}}
+
+typedef char *my_va_list;
+void __cdecl __va_start(my_va_list *ap, ...); // expected-note {{passing argument to parameter 'ap' here}}
+void vmyprintf(const char *f, my_va_list ap);
+void myprintf(const char *f, ...) {
+  my_va_list ap;
+  if (1) {
+    __va_start(&ap, f);
+    vmyprintf(f, ap);
+    ap = 0;
+  } else {
+    __va_start(ap, f); // expected-warning {{incompatible pointer types passing 'my_va_list'}}
+  }
+}