[MC] Pass down argv0 & cc1 cmd-line to the back-end and store in MCTargetOptions

When targetting CodeView, the goal is to store argv0 & cc1 cmd-line in the emitted .OBJ, in order to allow a reproducer from the .OBJ alone.

This patch is to simplify https://reviews.llvm.org/D80833

clang/include/clang/Basic/CodeGenOptions.h

@@ -332,6 +332,11 @@ public:
   /// coverage pass should actually not be instrumented.
   std::vector<std::string> SanitizeCoverageBlacklistFiles;
 
+  /// Executable and command-line used to create a given CompilerInvocation.
+  /// Most of the time this will be the full -cc1 command.
+  const char *Argv0 = nullptr;
+  ArrayRef<const char *> CommandLineArgs;
+
 public:
   // Define accessors/mutators for code generation options of enumeration type.
 #define CODEGENOPT(Name, Bits, Default)

clang/include/clang/Frontend/CompilerInvocation.h

@@ -155,7 +155,8 @@ public:
   /// \param [out] Res - The resulting invocation.
   static bool CreateFromArgs(CompilerInvocation &Res,
                              ArrayRef<const char *> CommandLineArgs,
-                             DiagnosticsEngine &Diags);
+                             DiagnosticsEngine &Diags,
+                             const char *Argv0 = nullptr);
 
   /// Get the directory where the compiler headers
   /// reside, relative to the compiler binary (found by the passed in

clang/lib/CodeGen/BackendUtil.cpp

@@ -537,6 +537,8 @@ static void initTargetOptions(DiagnosticsEngine &Diags,
          Entry.Group == frontend::IncludeDirGroup::System))
       Options.MCOptions.IASSearchPaths.push_back(
           Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
+  Options.MCOptions.Argv0 = CodeGenOpts.Argv0;
+  Options.MCOptions.CommandLineArgs = CodeGenOpts.CommandLineArgs;
 }
 static Optional<GCOVOptions> getGCOVOptions(const CodeGenOptions &CodeGenOpts) {
   if (CodeGenOpts.DisableGCov)

clang/lib/Frontend/CompilerInvocation.cpp

@@ -3627,7 +3627,8 @@ static void ParseTargetArgs(TargetOptions &Opts, ArgList &Args,
 
 bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
                                         ArrayRef<const char *> CommandLineArgs,
-                                        DiagnosticsEngine &Diags) {
+                                        DiagnosticsEngine &Diags,
+                                        const char *Argv0) {
   bool Success = true;
 
   // Parse the arguments.
@@ -3747,6 +3748,11 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
     Res.getCodeGenOpts().FineGrainedBitfieldAccesses = false;
     Diags.Report(diag::warn_drv_fine_grained_bitfield_accesses_ignored);
   }
+
+  // Store the command-line for using in the CodeView backend.
+  Res.getCodeGenOpts().Argv0 = Argv0;
+  Res.getCodeGenOpts().CommandLineArgs = CommandLineArgs;
+
   return Success;
 }
 

clang/lib/Frontend/CreateInvocationFromCommandLine.cpp

@@ -93,7 +93,7 @@ std::unique_ptr<CompilerInvocation> clang::createInvocationFromCommandLine(
   if (CC1Args)
     *CC1Args = {CCArgs.begin(), CCArgs.end()};
   auto CI = std::make_unique<CompilerInvocation>();
-  if (!CompilerInvocation::CreateFromArgs(*CI, CCArgs, *Diags) &&
+  if (!CompilerInvocation::CreateFromArgs(*CI, CCArgs, *Diags, Args[0]) &&
       !ShouldRecoverOnErorrs)
     return nullptr;
   return CI;

clang/lib/Tooling/Tooling.cpp

@@ -141,11 +141,13 @@ namespace clang {
 namespace tooling {
 
 /// Returns a clang build invocation initialized from the CC1 flags.
-CompilerInvocation *newInvocation(
-    DiagnosticsEngine *Diagnostics, const llvm::opt::ArgStringList &CC1Args) {
+CompilerInvocation *newInvocation(DiagnosticsEngine *Diagnostics,
+                                  const llvm::opt::ArgStringList &CC1Args,
+                                  const char *const BinaryName) {
   assert(!CC1Args.empty() && "Must at least contain the program name!");
   CompilerInvocation *Invocation = new CompilerInvocation;
-  CompilerInvocation::CreateFromArgs(*Invocation, CC1Args, *Diagnostics);
+  CompilerInvocation::CreateFromArgs(*Invocation, CC1Args, *Diagnostics,
+                                     BinaryName);
   Invocation->getFrontendOpts().DisableFree = false;
   Invocation->getCodeGenOpts().DisableFree = false;
   return Invocation;
@@ -345,7 +347,7 @@ bool ToolInvocation::run() {
   if (!CC1Args)
     return false;
   std::unique_ptr<CompilerInvocation> Invocation(
-      newInvocation(&Diagnostics, *CC1Args));
+      newInvocation(&Diagnostics, *CC1Args, BinaryName));
   // FIXME: remove this when all users have migrated!
   for (const auto &It : MappedFileContents) {
     // Inject the code as the given file name into the preprocessor options.

clang/tools/driver/cc1_main.cpp

@@ -203,8 +203,8 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
   TextDiagnosticBuffer *DiagsBuffer = new TextDiagnosticBuffer;
   DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagsBuffer);
-  bool Success =
-      CompilerInvocation::CreateFromArgs(Clang->getInvocation(), Argv, Diags);
+  bool Success = CompilerInvocation::CreateFromArgs(Clang->getInvocation(),
+                                                    Argv, Diags, Argv0);
 
   if (Clang->getFrontendOpts().TimeTrace) {
     llvm::timeTraceProfilerInitialize(

clang/tools/driver/driver.cpp

@@ -327,7 +327,7 @@ static int ExecuteCC1Tool(SmallVectorImpl<const char *> &ArgV) {
   StringRef Tool = ArgV[1];
   void *GetExecutablePathVP = (void *)(intptr_t)GetExecutablePath;
   if (Tool == "-cc1")
-    return cc1_main(makeArrayRef(ArgV).slice(2), ArgV[0], GetExecutablePathVP);
+    return cc1_main(makeArrayRef(ArgV).slice(1), ArgV[0], GetExecutablePathVP);
   if (Tool == "-cc1as")
     return cc1as_main(makeArrayRef(ArgV).slice(2), ArgV[0],
                       GetExecutablePathVP);

llvm/include/llvm/MC/MCTargetOptions.h

@@ -9,6 +9,7 @@
 #ifndef LLVM_MC_MCTARGETOPTIONS_H
 #define LLVM_MC_MCTARGETOPTIONS_H
 
+#include "llvm/ADT/ArrayRef.h"
 #include <string>
 #include <vector>
 
@@ -60,6 +61,9 @@ public:
   std::string AssemblyLanguage;
   std::string SplitDwarfFile;
 
+  const char *Argv0 = nullptr;
+  ArrayRef<const char *> CommandLineArgs;
+
   /// Additional paths to search for `.include` directives when using the
   /// integrated assembler.
   std::vector<std::string> IASSearchPaths;