Drop non-cfi assembly support from clang.

After this patch clang will ignore -fdwarf2-cfi-asm and -ffno-dwarf2-cfi-asm and
always print assembly that uses cfi directives.

In llvm, MC itself supports cfi since the end of 2010 (support started
in r119972, is reported in the 2.9 release notes).

In binutils the support has been around for much longer. It looks like
support started to be added in May 2003. It is available in 2.15
(31-Aug-2011, 2.14 is from 12-Jun-2003).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@207602 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Driver/Options.td

@@ -441,8 +441,8 @@ def fdiagnostics_show_template_tree : Flag<["-"], "fdiagnostics-show-template-tr
     HelpText<"Print a template comparison tree for differing templates">;
 def fdollars_in_identifiers : Flag<["-"], "fdollars-in-identifiers">, Group<f_Group>,
   HelpText<"Allow '$' in identifiers">, Flags<[CC1Option]>;
-def fdwarf2_cfi_asm : Flag<["-"], "fdwarf2-cfi-asm">, Group<f_Group>;
-def fno_dwarf2_cfi_asm : Flag<["-"], "fno-dwarf2-cfi-asm">, Group<f_Group>,  Flags<[CC1Option]>;
+def fdwarf2_cfi_asm : Flag<["-"], "fdwarf2-cfi-asm">, Group<clang_ignored_f_Group>;
+def fno_dwarf2_cfi_asm : Flag<["-"], "fno-dwarf2-cfi-asm">, Group<clang_ignored_f_Group>;
 def fdwarf_directory_asm : Flag<["-"], "fdwarf-directory-asm">, Group<f_Group>;
 def fno_dwarf_directory_asm : Flag<["-"], "fno-dwarf-directory-asm">, Group<f_Group>, Flags<[CC1Option]>;
 def felide_constructors : Flag<["-"], "felide-constructors">, Group<f_Group>;

include/clang/Frontend/CodeGenOptions.def

@@ -68,7 +68,6 @@ CODEGENOPT(LessPreciseFPMAD  , 1, 0) ///< Enable less precise MAD instructions t
                                      ///< be generated.
 CODEGENOPT(MergeAllConstants , 1, 1) ///< Merge identical constants.
 CODEGENOPT(NoCommon          , 1, 0) ///< Set when -fno-common or C++ is enabled.
-CODEGENOPT(NoDwarf2CFIAsm    , 1, 0) ///< Set when -fno-dwarf2-cfi-asm is enabled.
 CODEGENOPT(NoDwarfDirectoryAsm , 1, 0) ///< Set when -fno-dwarf-directory-asm is
                                        ///< enabled.
 CODEGENOPT(NoExecStack       , 1, 0) ///< Set when -Wa,--noexecstack is enabled.

lib/CodeGen/BackendUtil.cpp

@@ -503,8 +503,6 @@ TargetMachine *EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
     TM->setMCRelaxAll(true);
   if (CodeGenOpts.SaveTempLabels)
     TM->setMCSaveTempLabels(true);
-  if (CodeGenOpts.NoDwarf2CFIAsm)
-    TM->setMCUseCFI(false);
   if (!CodeGenOpts.NoDwarfDirectoryAsm)
     TM->setMCUseDwarfDirectory(true);
   if (CodeGenOpts.NoExecStack)

lib/Driver/Tools.cpp

@@ -1733,19 +1733,6 @@ static bool ShouldDisableAutolink(const ArgList &Args,
                        Default);
 }
 
-static bool ShouldDisableCFI(const ArgList &Args,
-                             const ToolChain &TC) {
-  bool Default = true;
-  if (TC.getTriple().isOSDarwin()) {
-    // The native darwin assembler doesn't support cfi directives, so
-    // we disable them if we think the .s file will be passed to it.
-    Default = TC.useIntegratedAs();
-  }
-  return !Args.hasFlag(options::OPT_fdwarf2_cfi_asm,
-                       options::OPT_fno_dwarf2_cfi_asm,
-                       Default);
-}
-
 static bool ShouldDisableDwarfDirectory(const ArgList &Args,
                                         const ToolChain &TC) {
   bool UseDwarfDirectory = Args.hasFlag(options::OPT_fdwarf_directory_asm,
@@ -3138,9 +3125,6 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
       CmdArgs.push_back("-fno-gnu-keywords");
   }
 
-  if (ShouldDisableCFI(Args, getToolChain()))
-    CmdArgs.push_back("-fno-dwarf2-cfi-asm");
-
   if (ShouldDisableDwarfDirectory(Args, getToolChain()))
     CmdArgs.push_back("-fno-dwarf-directory-asm");
 

lib/Frontend/CompilerInvocation.cpp

@@ -399,7 +399,6 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.RelaxAll = Args.hasArg(OPT_mrelax_all);
   Opts.OmitLeafFramePointer = Args.hasArg(OPT_momit_leaf_frame_pointer);
   Opts.SaveTempLabels = Args.hasArg(OPT_msave_temp_labels);
-  Opts.NoDwarf2CFIAsm = Args.hasArg(OPT_fno_dwarf2_cfi_asm);
   Opts.NoDwarfDirectoryAsm = Args.hasArg(OPT_fno_dwarf_directory_asm);
   Opts.SoftFloat = Args.hasArg(OPT_msoft_float);
   Opts.StrictEnums = Args.hasArg(OPT_fstrict_enums);

test/Driver/cfi.c

@@ -1,9 +0,0 @@
-// RUN: %clang -target i386-apple-darwin10 \
-// RUN:    -no-integrated-as -### %s 2>&1 | \
-// RUN:  FileCheck --check-prefix=CHECK-DARWIN %s
-
-// RUN: %clang -target i386-pc-linux-gnu  -static -### %s 2>&1 | \
-// RUN: FileCheck --check-prefix=CHECK-LINUX %s
-
-// CHECK-DARWIN: -fno-dwarf2-cfi-asm
-// CHECK-LINUX-NOT: -fno-dwarf2-cfi-asm

test/Driver/dwarf2-cfi-asm.c

@@ -1,35 +0,0 @@
-// RUN: %clang -target x86_64-apple-darwin -### -S -integrated-as %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-DARWIN-MC-DEFAULT %s
-// RUN: %clang -target x86_64-apple-darwin -### -S -integrated-as -fdwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-DARWIN-MC-CFI %s
-// RUN: %clang -target x86_64-apple-darwin -### -S -integrated-as -fno-dwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-DARWIN-MC-NOCFI %s
-
-// RUN: %clang -target x86_64-apple-darwin -### -S -no-integrated-as %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-DARWIN-AS-DEFAULT %s
-// RUN: %clang -target x86_64-apple-darwin -### -S -no-integrated-as -fdwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-DARWIN-AS-CFI %s
-// RUN: %clang -target x86_64-apple-darwin -### -S -no-integrated-as -fno-dwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-DARWIN-AS-NOCFI %s
-
-
-// RUN: %clang -target x86_64-pc-linux -### -S -integrated-as %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-LINUX-MC-DEFAULT %s
-// RUN: %clang -target x86_64-pc-linux -### -S -integrated-as -fdwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-LINUX-MC-CFI %s
-// RUN: %clang -target x86_64-pc-linux -### -S -integrated-as -fno-dwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-LINUX-MC-NOCFI %s
-
-// RUN: %clang -target x86_64-pc-linux -### -S -no-integrated-as %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-LINUX-AS-DEFAULT %s
-// RUN: %clang -target x86_64-pc-linux -### -S -no-integrated-as -fdwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-LINUX-AS-CFI %s
-// RUN: %clang -target x86_64-pc-linux -### -S -no-integrated-as -fno-dwarf2-cfi-asm %s -o %t.s 2>&1 | FileCheck -check-prefix=CHECK-LINUX-AS-NOCFI %s
-
-
-
-// CHECK-DARWIN-MC-DEFAULT-NOT: -fno-dwarf2-cfi-asm
-// CHECK-DARWIN-MC-CFI-NOT: -fno-dwarf2-cfi-asm
-// CHECK-DARWIN-MC-NOCFI: -fno-dwarf2-cfi-asm
-
-// CHECK-DARWIN-AS-DEFAULT: -fno-dwarf2-cfi-asm
-// CHECK-DARWIN-AS-CFI-NOT: -fno-dwarf2-cfi-asm
-// CHECK-DARWIN-AS-NOCFI: -fno-dwarf2-cfi-asm
-
-
-// CHECK-LINUX-MC-DEFAULT-NOT: -fno-dwarf2-cfi-asmx
-// CHECK-LINUX-MC-CFI-NOT: -fno-dwarf2-cfi-asm
-// CHECK-LINUX-MC-NOCFI: -fno-dwarf2-cfi-asm
-
-// CHECK-LINUX-AS-DEFAULT-NOT: -fno-dwarf2-cfi-asm
-// CHECK-LINUX-AS-CFI-NOT: -fno-dwarf2-cfi-asm
-// CHECK-LINUX-AS-NOCFI: -fno-dwarf2-cfi-asm