[clang] Make "__GCC_HAVE_DWARF2_CFI_ASM" a proper predefined macro

clang-tools-extra/test/pp-trace/pp-trace-include.cpp

@@ -39,7 +39,6 @@
 // CHECK-NEXT:   Reason: EnterFile
 // CHECK-NEXT:   FileType: C_User
 // CHECK-NEXT:   PrevFID: (invalid)
-// CHECK:      - Callback: MacroDefined
 // CHECK:      - Callback: FileChanged
 // CHECK-NEXT:   Loc: "<built-in>:1:1"
 // CHECK-NEXT:   Reason: ExitFile

clang-tools-extra/test/pp-trace/pp-trace-macro.cpp

@@ -40,7 +40,6 @@ X
 // CHECK-NEXT:   MacroNameTok: __STDC_EMBED_EMPTY__
 // CHECK-NEXT:   MacroDirective: MD_Define
 // CHECK:      - Callback: MacroDefined
-// CHECK:      - Callback: MacroDefined
 // CHECK-NEXT:   MacroNameTok: MACRO
 // CHECK-NEXT:   MacroDirective: MD_Define
 // CHECK-NEXT: - Callback: MacroExpands

clang/include/clang/Basic/DebugOptions.def

@@ -46,6 +46,8 @@ ENUM_DEBUGOPT(EmitDwarfUnwind, EmitDwarfUnwindType, 2,
 DEBUGOPT(NoDwarfDirectoryAsm , 1, 0, Benign) ///< Set when -fno-dwarf-directory-asm
                                              ///< is enabled.
 
+DEBUGOPT(Dwarf2CFIAsm, 1, 0, NotCompatible) ///< Set when -fdwarf2-cfi-asm is enabled.
+
 DEBUGOPT(NoInlineLineTables, 1, 0, Benign) ///< Whether debug info should contain
                                            ///< inline line tables.
 

clang/include/clang/Driver/Options.td

@@ -2155,8 +2155,12 @@ defm dollars_in_identifiers : BoolFOption<"dollars-in-identifiers",
   PosFlag<SetTrue, [], [ClangOption], "Allow">,
   NegFlag<SetFalse, [], [ClangOption], "Disallow">,
   BothFlags<[], [ClangOption, CC1Option], " '$' in identifiers">>;
-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>;
+
+defm dwarf2_cfi_asm
+    : BoolFOption<"dwarf2-cfi-asm", CodeGenOpts<"Dwarf2CFIAsm">, DefaultFalse,
+                  PosFlag<SetTrue, [], [ClangOption, CC1Option]>,
+                  NegFlag<SetFalse>>;
+
 defm dwarf_directory_asm : BoolFOption<"dwarf-directory-asm",
   CodeGenOpts<"NoDwarfDirectoryAsm">, DefaultFalse,
   NegFlag<SetTrue, [], [ClangOption, CC1Option]>,

clang/lib/Driver/ToolChains/Clang.cpp

@@ -7879,10 +7879,13 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
                        !TC.getTriple().isAndroid() && TC.useIntegratedAs()))
     CmdArgs.push_back("-faddrsig");
 
-  if ((Triple.isOSBinFormatELF() || Triple.isOSBinFormatMachO()) &&
+  const bool HasDefaultDwarf2CFIASM =
+      (Triple.isOSBinFormatELF() || Triple.isOSBinFormatMachO()) &&
       (EH || UnwindTables || AsyncUnwindTables ||
-       DebugInfoKind != llvm::codegenoptions::NoDebugInfo))
-    CmdArgs.push_back("-D__GCC_HAVE_DWARF2_CFI_ASM=1");
+       DebugInfoKind != llvm::codegenoptions::NoDebugInfo);
+  if (Args.hasFlag(options::OPT_fdwarf2_cfi_asm,
+                   options::OPT_fno_dwarf2_cfi_asm, HasDefaultDwarf2CFIASM))
+    CmdArgs.push_back("-fdwarf2-cfi-asm");
 
   if (Arg *A = Args.getLastArg(options::OPT_fsymbol_partition_EQ)) {
     std::string Str = A->getAsString(Args);

clang/lib/Frontend/InitPreprocessor.cpp

@@ -1516,6 +1516,9 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
   if (LangOpts.PointerAuthIntrinsics)
     Builder.defineMacro("__PTRAUTH__");
 
+  if (CGOpts.Dwarf2CFIAsm)
+    Builder.defineMacro("__GCC_HAVE_DWARF2_CFI_ASM");
+
   // Get other target #defines.
   TI.getTargetDefines(LangOpts, Builder);
 }

clang/test/DebugInfo/KeyInstructions/flag.cpp

@@ -8,6 +8,9 @@
 
 // KEY-INSTRUCTIONS: "-gkey-instructions"
 // NO-KEY-INSTRUCTIONS-NOT: key-instructions
+
+// Only expect one dwarf related flag.
+// NO-DEBUG: -fdwarf2-cfi-asm
 // NO-DEBUG-NOT: debug-info-kind
 // NO-DEBUG-NOT: dwarf
 

clang/test/Preprocessor/unwind-tables.c

@@ -1,11 +1,13 @@
 // RUN: %clang %s -dM -E -target x86_64-windows | FileCheck %s --check-prefix=NO
 // RUN: %clang %s -dM -E -target x86_64 -fno-asynchronous-unwind-tables | FileCheck %s --check-prefix=NO
+// RUN: %clang %s -dM -E -target x86_64 -fno-dwarf2-cfi-asm | FileCheck %s --check-prefix=NO
 
 // RUN: %clang %s -dM -E -target x86_64 | FileCheck %s
 // RUN: %clang %s -dM -E -target x86_64 -funwind-tables -fno-asynchronous-unwind-tables -g | FileCheck %s
 // RUN: %clang %s -dM -E -target aarch64-apple-darwin | FileCheck %s
 // RUN: %clang %s -dM -E -target x86_64 -fno-asynchronous-unwind-tables -g | FileCheck %s
 // RUN: %clang %s -dM -E -target x86_64 -fno-asynchronous-unwind-tables -fexceptions | FileCheck %s
+// RUN: %clang %s -dM -E -target x86_64-windows -fdwarf2-cfi-asm | FileCheck %s
 
 // NO-NOT: #define __GCC_HAVE_DWARF2_CFI_ASM
 // CHECK: #define __GCC_HAVE_DWARF2_CFI_ASM 1