[ms-inline asm] Add an error when trying to compile MS-style inline assembly

for an unsupported architecture.
rdar://13063988

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173364 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Basic/DiagnosticSemaKinds.td

@@ -5241,6 +5241,8 @@ let CategoryName = "Inline Assembly Issue" in {
     "invalid use of a cast in a inline asm context requiring an l-value: "
     "remove the cast or build with -fheinous-gnu-extensions">;
   def err_inline_ms_asm_parsing : Error<"%0">;
+  def err_msasm_unsupported_arch : Error<
+    "Unsupported architecture '%0' for MS-style inline assembly">;
 
   def warn_asm_label_on_auto_decl : Warning<
     "ignored asm label '%0' on automatic variable">;

lib/Sema/SemaStmtAsm.cpp

@@ -580,8 +580,15 @@ StmtResult Sema::ActOnMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc,
   SmallVector<Expr*, 4> Exprs;
   SmallVector<StringRef, 4> ClobberRefs;
 
+  llvm::Triple TheTriple = Context.getTargetInfo().getTriple();
+  llvm::Triple::ArchType ArchTy = TheTriple.getArch();
+  bool UnsupportedArch = ArchTy != llvm::Triple::x86 &&
+    ArchTy != llvm::Triple::x86_64;
+  if (UnsupportedArch)
+    Diag(AsmLoc, diag::err_msasm_unsupported_arch) << TheTriple.getArchName();
+    
   // Empty asm statements don't need to instantiate the AsmParser, etc.
-  if (AsmToks.empty()) {
+  if (UnsupportedArch || AsmToks.empty()) {
     StringRef EmptyAsmStr;
     MSAsmStmt *NS =
       new (Context) MSAsmStmt(Context, AsmLoc, LBraceLoc, /*IsSimple*/ true,
@@ -598,7 +605,7 @@ StmtResult Sema::ActOnMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc,
 
   // Get the target specific parser.
   std::string Error;
-  const std::string &TT = Context.getTargetInfo().getTriple().getTriple();
+  const std::string &TT = TheTriple.getTriple();
   const llvm::Target *TheTarget(llvm::TargetRegistry::lookupTarget(TT, Error));
 
   OwningPtr<llvm::MCAsmInfo> MAI(TheTarget->createMCAsmInfo(TT));

test/Sema/ms-inline-asm-invalid-arch.c

@@ -0,0 +1,5 @@
+// RUN: %clang_cc1 %s -triple powerpc64-unknown-linux-gnu -fasm-blocks -verify -fsyntax-only
+
+void f() {
+  __asm nop // expected-error {{Unsupported architecture 'powerpc64' for MS-style inline assembly}}
+}