[clang-cl] Add support for /Zd

MASM (ML.exe and ML64.exe) and older versions of MSVC (CL.exe) support a
flag called /Zd which is more-or-less -gline-tables-only.

It seems nicer to support this flag instead of exposing
-gline-tables-only.

llvm-svn: 274991

clang/include/clang/Driver/CLCompatOptions.td

@@ -166,6 +166,8 @@ def _SLASH_Zc_trigraphs_off : CLFlag<"Zc:trigraphs-">,
   HelpText<"Disable trigraphs (default)">, Alias<fno_trigraphs>;
 def _SLASH_Z7 : CLFlag<"Z7">,
   HelpText<"Enable CodeView debug information in object files">;
+def _SLASH_Zd : CLFlag<"Zd">,
+  HelpText<"Emit debug line number tables only">;
 def _SLASH_Zi : CLFlag<"Zi">, Alias<_SLASH_Z7>,
   HelpText<"Alias for /Z7. Does not produce PDBs.">;
 def _SLASH_Zp : CLJoined<"Zp">,

clang/include/clang/Driver/Options.td

@@ -1229,7 +1229,7 @@ def fdebug_prefix_map_EQ
 def g_Flag : Flag<["-"], "g">, Group<g_Group>,
   HelpText<"Generate source-level debug information">;
 def gline_tables_only : Flag<["-"], "gline-tables-only">, Group<gN_Group>,
-  Flags<[CoreOption]>, HelpText<"Emit debug line number tables only">;
+  HelpText<"Emit debug line number tables only">;
 def gmlt : Flag<["-"], "gmlt">, Alias<gline_tables_only>;
 def g0 : Flag<["-"], "g0">, Group<gN_Group>;
 def g1 : Flag<["-"], "g1">, Group<gN_Group>, Alias<gline_tables_only>;

clang/lib/Driver/Tools.cpp

@@ -6269,12 +6269,18 @@ void Clang::AddClangCLArgs(const ArgList &Args, types::ID InputType,
     CmdArgs.push_back(Args.MakeArgString(Twine(LangOptions::SSPStrong)));
   }
 
-  // Emit CodeView if -Z7 is present.
-  *EmitCodeView = Args.hasArg(options::OPT__SLASH_Z7);
-  if (*EmitCodeView)
-    *DebugInfoKind = codegenoptions::LimitedDebugInfo;
-  if (*EmitCodeView)
+  // Emit CodeView if -Z7 or -Zd are present.
+  if (Arg *DebugInfoArg =
+          Args.getLastArg(options::OPT__SLASH_Z7, options::OPT__SLASH_Zd)) {
+    *EmitCodeView = true;
+    if (DebugInfoArg->getOption().matches(options::OPT__SLASH_Z7))
+      *DebugInfoKind = codegenoptions::LimitedDebugInfo;
+    else
+      *DebugInfoKind = codegenoptions::DebugLineTablesOnly;
     CmdArgs.push_back("-gcodeview");
+  } else {
+    *EmitCodeView = false;
+  }
 
   const Driver &D = getToolChain().getDriver();
   EHFlags EH = parseClangCLEHFlags(D, Args);
@@ -9964,7 +9970,8 @@ void visualstudio::Linker::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back("-nologo");
 
-  if (Args.hasArg(options::OPT_g_Group, options::OPT__SLASH_Z7))
+  if (Args.hasArg(options::OPT_g_Group, options::OPT__SLASH_Z7,
+                  options::OPT__SLASH_Zd))
     CmdArgs.push_back("-debug");
 
   bool DLL = Args.hasArg(options::OPT__SLASH_LD, options::OPT__SLASH_LDd,

clang/test/Driver/cl-options.c

@@ -420,7 +420,7 @@
 // Z7: "-gcodeview"
 // Z7: "-debug-info-kind=limited"
 
-// RUN: %clang_cl -gline-tables-only /Z7 /c -### -- %s 2>&1 | FileCheck -check-prefix=Z7GMLT %s
+// RUN: %clang_cl /Zd /c -### -- %s 2>&1 | FileCheck -check-prefix=Z7GMLT %s
 // Z7GMLT: "-gcodeview"
 // Z7GMLT: "-debug-info-kind=line-tables-only"