Add support for MSVC __unaligned attribute. Necessary to parse MSVC headers in 64-bit mode (ie: when _M_IA64 or _M_AMD64 is defined)

more info: http://msdn.microsoft.com/en-us/library/ms177389.aspx

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@137935 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/TokenKinds.def b/include/clang/Basic/TokenKinds.def
index d057559..95bfca4 100644
--- a/include/clang/Basic/TokenKinds.def
+++ b/include/clang/Basic/TokenKinds.def
@@ -405,6 +405,7 @@
 KEYWORD(__fastcall                  , KEYALL)
 KEYWORD(__thiscall                  , KEYALL)
 KEYWORD(__forceinline               , KEYALL)
+KEYWORD(__unaligned                 , KEYMS)
 
 // OpenCL-specific keywords
 KEYWORD(__kernel                    , KEYOPENCL)
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 2a95ecc..9023b34 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -302,7 +302,8 @@
   // FIXME: Allow Sema to distinguish between these and real attributes!
   while (Tok.is(tok::kw___fastcall) || Tok.is(tok::kw___stdcall) ||
          Tok.is(tok::kw___thiscall) || Tok.is(tok::kw___cdecl)   ||
-         Tok.is(tok::kw___ptr64) || Tok.is(tok::kw___w64)) {
+         Tok.is(tok::kw___ptr64) || Tok.is(tok::kw___w64) ||
+         Tok.is(tok::kw___unaligned)) {
     IdentifierInfo *AttrName = Tok.getIdentifierInfo();
     SourceLocation AttrNameLoc = ConsumeToken();
     if (Tok.is(tok::kw___ptr64) || Tok.is(tok::kw___w64))
@@ -1726,6 +1727,7 @@
     case tok::kw___stdcall:
     case tok::kw___fastcall:
     case tok::kw___thiscall:
+    case tok::kw___unaligned:
       ParseMicrosoftTypeAttributes(DS.getAttributes());
       continue;
 
@@ -2274,6 +2276,7 @@
   case tok::kw___stdcall:
   case tok::kw___fastcall:
   case tok::kw___thiscall:
+  case tok::kw___unaligned:
     ParseMicrosoftTypeAttributes(DS.getAttributes());
     return true;
 
@@ -2982,6 +2985,7 @@
   case tok::kw___w64:
   case tok::kw___ptr64:
   case tok::kw___pascal:
+  case tok::kw___unaligned:
 
   case tok::kw___private:
   case tok::kw___local:
@@ -3129,6 +3133,7 @@
   case tok::kw___ptr64:
   case tok::kw___forceinline:
   case tok::kw___pascal:
+  case tok::kw___unaligned:
 
   case tok::kw___private:
   case tok::kw___local:
@@ -3264,6 +3269,7 @@
     case tok::kw___stdcall:
     case tok::kw___fastcall:
     case tok::kw___thiscall:
+    case tok::kw___unaligned:
       if (VendorAttributesAllowed) {
         ParseMicrosoftTypeAttributes(DS.getAttributes());
         continue;
@@ -3676,7 +3682,8 @@
   // Eat any Microsoft extensions.
   if  (Tok.is(tok::kw___cdecl) || Tok.is(tok::kw___stdcall) ||
        Tok.is(tok::kw___thiscall) || Tok.is(tok::kw___fastcall) ||
-       Tok.is(tok::kw___w64) || Tok.is(tok::kw___ptr64)) {
+       Tok.is(tok::kw___w64) || Tok.is(tok::kw___ptr64) ||
+       Tok.is(tok::kw___unaligned)) {
     ParseMicrosoftTypeAttributes(attrs);
   }
   // Eat any Borland extensions.
diff --git a/lib/Parse/ParseTentative.cpp b/lib/Parse/ParseTentative.cpp
index 3f245a3..e354f57 100644
--- a/lib/Parse/ParseTentative.cpp
+++ b/lib/Parse/ParseTentative.cpp
@@ -552,7 +552,8 @@
           Tok.is(tok::kw___cdecl) ||
           Tok.is(tok::kw___stdcall) ||
           Tok.is(tok::kw___fastcall) ||
-          Tok.is(tok::kw___thiscall))
+          Tok.is(tok::kw___thiscall) ||
+          Tok.is(tok::kw___unaligned))

         return TPResult::True(); // attributes indicate declaration
       TPResult TPR = TryParseDeclarator(mayBeAbstract, mayHaveIdentifier);
       if (TPR != TPResult::Ambiguous())
@@ -711,6 +712,7 @@
   case tok::kw___stdcall:
   case tok::kw___fastcall:
   case tok::kw___thiscall:
+  case tok::kw___unaligned:

   case tok::kw___vector:
   case tok::kw___pixel:
     return TPResult::False();
@@ -903,6 +905,7 @@
   case tok::kw___w64:
   case tok::kw___ptr64:
   case tok::kw___forceinline:
+  case tok::kw___unaligned:

     return TPResult::True();
 
     // Borland
diff --git a/test/SemaCXX/MicrosoftExtensions.cpp b/test/SemaCXX/MicrosoftExtensions.cpp
index 9b03feb..db6d30a 100644
--- a/test/SemaCXX/MicrosoftExtensions.cpp
+++ b/test/SemaCXX/MicrosoftExtensions.cpp
@@ -81,6 +81,10 @@
     float __stdcall subtractP(); 
 };
 
+// __unaligned handling
+typedef char __unaligned *aligned_type;
+
+
 template<typename T> void h1(T (__stdcall M::* const )()) { }
 
 void m1() {