Adding option -fno-inline-asm to disallow inline asm

Summary:
This patch add a new option to dis-allow all inline asm.
Any GCC style inline asm will be reported as an error.

Reviewers: rnk, echristo

Reviewed By: rnk, echristo

Subscribers: bob.wilson, rnk, echristo, rsmith, cfe-commits

Differential Revision: http://reviews.llvm.org/D6870

llvm-svn: 226340

clang/include/clang/Basic/DiagnosticParseKinds.td

@@ -25,6 +25,8 @@ def err_msasm_unsupported_arch : Error<
   "Unsupported architecture '%0' for MS-style inline assembly">;
 def err_msasm_unable_to_create_target : Error<
   "MS-style inline assembly is not available: %0">;
+def err_gnu_inline_asm_disabled : Error<
+  "GNU-style inline assembly is disabled">;
 }
 
 let CategoryName = "Parse Issue" in {

clang/include/clang/Basic/LangOptions.def

@@ -114,6 +114,7 @@ LANGOPT(MSBitfields       , 1, 0, "Microsoft-compatible structure layout")
 LANGOPT(Freestanding, 1, 0, "freestanding implementation")
 LANGOPT(NoBuiltin         , 1, 0, "disable builtin functions")
 LANGOPT(NoMathBuiltin     , 1, 0, "disable math builtin functions")
+LANGOPT(GNUAsm            , 1, 1, "GNU-style inline assembly")
 
 BENIGN_LANGOPT(ThreadsafeStatics , 1, 1, "thread-safe static initializers")
 LANGOPT(POSIXThreads      , 1, 0, "POSIX thread support")

clang/include/clang/Driver/Options.td

@@ -404,6 +404,11 @@ def fno_autolink : Flag <["-"], "fno-autolink">, Group<f_Group>,
   Flags<[DriverOption, CC1Option]>,
   HelpText<"Disable generation of linker directives for automatic library linking">;
 
+def fgnu_inline_asm : Flag<["-"], "fgnu-inline-asm">, Group<f_Group>, Flags<[DriverOption]>;
+def fno_gnu_inline_asm : Flag<["-"], "fno-gnu-inline-asm">, Group<f_Group>,
+  Flags<[DriverOption, CC1Option]>,
+  HelpText<"Disable GNU style inline asm">;
+
 def fprofile_sample_use_EQ : Joined<["-"], "fprofile-sample-use=">,
     Group<f_Group>, Flags<[DriverOption, CC1Option]>,
     HelpText<"Enable sample-based profile guided optimizations">;

clang/lib/Driver/Tools.cpp

@@ -4320,6 +4320,11 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                    false))
     CmdArgs.push_back("-fasm-blocks");
 
+  // -fgnu-inline-asm is default.
+  if (!Args.hasFlag(options::OPT_fgnu_inline_asm,
+                    options::OPT_fno_gnu_inline_asm, true))
+    CmdArgs.push_back("-fno-gnu-inline-asm");
+
   // Enable vectorization per default according to the optimization level
   // selected. For optimization levels that want vectorization we use the alias
   // option to simplify the hasFlag logic.

clang/lib/Frontend/CompilerInvocation.cpp

@@ -1563,6 +1563,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
       Args.getLastArgValue(OPT_fmodule_implementation_of);
   Opts.NativeHalfType = Opts.NativeHalfType;
   Opts.HalfArgsAndReturns = Args.hasArg(OPT_fallow_half_arguments_and_returns);
+  Opts.GNUAsm = !Args.hasArg(OPT_fno_gnu_inline_asm);
 
   if (!Opts.CurrentModule.empty() && !Opts.ImplementationOfModule.empty() &&
       Opts.CurrentModule != Opts.ImplementationOfModule) {

clang/lib/Parse/ParseStmtAsm.cpp

@@ -615,6 +615,11 @@ StmtResult Parser::ParseAsmStatement(bool &msAsm) {
     msAsm = true;
     return ParseMicrosoftAsmStatement(AsmLoc);
   }
+
+  // Check if GNU-style inline Asm is disabled.
+  if (!getLangOpts().GNUAsm)
+    Diag(AsmLoc, diag::err_gnu_inline_asm_disabled);
+
   DeclSpec DS(AttrFactory);
   SourceLocation Loc = Tok.getLocation();
   ParseTypeQualifierListOpt(DS, AR_VendorAttributesParsed);

clang/test/Driver/inline-asm.c

@@ -13,3 +13,12 @@
 // RUN: FileCheck --check-prefix=CHECK-NO-BLOCKS < %t %s
 
 // CHECK-NO-BLOCKS-NOT: "-fasm-blocks"
+
+// RUN: %clang -target x86_64-apple-darwin10 \
+// RUN:   -### -fsyntax-only -fno-gnu-inline-asm %s 2>&1 | \
+// RUN: FileCheck --check-prefix=CHECK-NO-GNU-INLINE-ASM %s
+// RUN: %clang -target x86_64-apple-darwin10 \
+// RUN:   -### -fsyntax-only -fgnu-inline-asm -fno-gnu-inline-asm %s 2>&1 | \
+// RUN: FileCheck --check-prefix=CHECK-NO-GNU-INLINE-ASM %s
+
+// CHECK-NO-GNU-INLINE-ASM: "-fno-gnu-inline-asm"

clang/test/Parser/ms-inline-asm.c

@@ -1,5 +1,7 @@
 // REQUIRES: x86-registered-target
 // RUN: %clang_cc1 %s -triple i386-apple-darwin10 -verify -fasm-blocks
+// Disabling gnu inline assembly should have no effect on this testcase
+// RUN: %clang_cc1 %s -triple i386-apple-darwin10 -verify -fasm-blocks -fno-gnu-inline-asm
 
 #define M __asm int 0x2c
 #define M2 int

clang/test/Parser/no-gnu-inline-asm.c

@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 %s -triple i686-apple-darwin -verify -fsyntax-only -fno-gnu-inline-asm
+
+void f (void) {
+  long long foo = 0, bar;
+  asm volatile("INST %0, %1" : "=r"(foo) : "r"(bar)); // expected-error {{GNU-style inline assembly is disabled}}
+  return;
+}