Revert "[flang][Driver] Support -print-supported-cpus and associated aliases (#117199)"

This reverts commit 23d7a6c, which added
support for PrecompileJobAction to LLVM Flang, in order to support the
-print-supported-cpus option in fc1. Currently, Classic Flang does not
support this option or the PrecompileJobAction.

Author: bryanpkc

Diff for: clang/include/clang/Driver/Options.td

@@ -6028,24 +6028,12 @@ def target : Joined<["--"], "target=">, Flags<[NoXarchOption]>,
 def darwin_target_variant : Separate<["-"], "darwin-target-variant">,
   Flags<[NoXarchOption]>, Visibility<[ClangOption, CLOption]>,
   HelpText<"Generate code for an additional runtime variant of the deployment target">;
-
-//===----------------------------------------------------------------------===//
-// Print CPU info options (clang, clang-cl, flang)
-//===----------------------------------------------------------------------===//
-
-let Visibility = [ClangOption, CC1Option, CLOption, FlangOption, FC1Option] in {
-
 def print_supported_cpus : Flag<["-", "--"], "print-supported-cpus">,
   Group<CompileOnly_Group>,
-  HelpText<"Print supported cpu models for the given target (if target is not "
-           "specified,it will print the supported cpus for the default target)">,
+  Visibility<[ClangOption, CC1Option, CLOption]>,
+  HelpText<"Print supported cpu models for the given target (if target is not specified,"
+           " it will print the supported cpus for the default target)">,
   MarshallingInfoFlag<FrontendOpts<"PrintSupportedCPUs">>;
-
-def : Flag<["-"], "mcpu=help">, Alias<print_supported_cpus>;
-def : Flag<["-"], "mtune=help">, Alias<print_supported_cpus>;
-
-} // let Visibility = [ClangOption, CC1Option, CLOption, FlangOption, FC1Option]
-
 def print_supported_extensions : Flag<["-", "--"], "print-supported-extensions">,
   Visibility<[ClangOption, CC1Option, CLOption]>,
   HelpText<"Print supported -march extensions (RISC-V, AArch64 and ARM only)">,
@@ -6055,6 +6043,8 @@ def print_enabled_extensions : Flag<["-", "--"], "print-enabled-extensions">,
   HelpText<"Print the extensions enabled by the given target and -march/-mcpu options."
            " (AArch64 and RISC-V only)">,
   MarshallingInfoFlag<FrontendOpts<"PrintEnabledExtensions">>;
+def : Flag<["-"], "mcpu=help">, Alias<print_supported_cpus>;
+def : Flag<["-"], "mtune=help">, Alias<print_supported_cpus>;
 def time : Flag<["-"], "time">,
   HelpText<"Time individual commands">;
 def traditional_cpp : Flag<["-", "--"], "traditional-cpp">,

Diff for: clang/lib/Driver/Driver.cpp

@@ -4634,8 +4634,7 @@ void Driver::BuildActions(Compilation &C, DerivedArgList &Args,
 
       // Use the -mcpu=? flag as the dummy input to cc1.
       Actions.clear();
-      Action *InputAc = C.MakeAction<InputAction>(
-          *A, IsFlangMode() ? types::TY_Fortran : types::TY_C);
+      Action *InputAc = C.MakeAction<InputAction>(*A, types::TY_C);
       Actions.push_back(
           C.MakeAction<PrecompileJobAction>(InputAc, types::TY_Nothing));
       for (auto &I : Inputs)
@@ -6904,8 +6903,7 @@ bool Driver::ShouldUseFlangCompiler(const JobAction &JA) const {
     return false;
 
   // And say "no" if this is not a kind of action flang understands.
-  if (!isa<PreprocessJobAction>(JA) && !isa<PrecompileJobAction>(JA) &&
-      !isa<CompileJobAction>(JA)
+  if (!isa<PreprocessJobAction>(JA) && !isa<CompileJobAction>(JA)
 #ifndef ENABLE_CLASSIC_FLANG
       && !isa<BackendJobAction>(JA)
 #endif

Diff for: clang/lib/Driver/ToolChains/Flang.cpp

@@ -777,9 +777,6 @@ void Flang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   } else if (isa<AssembleJobAction>(JA)) {
     CmdArgs.push_back("-emit-obj");
-  } else if (isa<PrecompileJobAction>(JA)) {
-    // The precompile job action is only needed for options such as -mcpu=help.
-    // Those will already have been handled by the fc1 driver.
   } else {
     assert(false && "Unexpected action class for Flang tool.");
   }
@@ -952,6 +949,8 @@ void Flang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back(Output.getFilename());
   }
 
+  assert(Input.isFilename() && "Invalid input.");
+
   if (Args.getLastArg(options::OPT_save_temps_EQ))
     Args.AddLastArg(CmdArgs, options::OPT_save_temps_EQ);
 
@@ -971,18 +970,7 @@ void Flang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
-  // The input could be Ty_Nothing when "querying" options such as -mcpu=help
-  // are used.
-  ArrayRef<InputInfo> FrontendInputs = Input;
-  if (Input.isNothing())
-    FrontendInputs = {};
-
-  for (const InputInfo &Input : FrontendInputs) {
-    if (Input.isFilename())
-      CmdArgs.push_back(Input.getFilename());
-    else
-      Input.getInputArg().renderAsInput(Args, CmdArgs);
-  }
+  CmdArgs.push_back(Input.getFilename());
 
   const char *Exec = Args.MakeArgString(D.GetProgramPath("flang", TC));
   C.addCommand(std::make_unique<Command>(JA, *this,

Diff for: flang/include/flang/Frontend/FrontendOptions.h

@@ -236,8 +236,7 @@ class FrontendInputFile {
 struct FrontendOptions {
   FrontendOptions()
       : showHelp(false), showVersion(false), instrumentedParse(false),
-        showColors(false), printSupportedCPUs(false),
-        needProvenanceRangeToCharBlockMappings(false) {}
+        showColors(false), needProvenanceRangeToCharBlockMappings(false) {}
 
   /// Show the -help text.
   unsigned showHelp : 1;
@@ -251,9 +250,6 @@ struct FrontendOptions {
   /// Enable color diagnostics.
   unsigned showColors : 1;
 
-  /// Print the supported cpus for the current target
-  unsigned printSupportedCPUs : 1;
-
   /// Enable Provenance to character-stream mapping. Allows e.g. IDEs to find
   /// symbols based on source-code location. This is not needed in regular
   /// compilation.

Diff for: flang/lib/Frontend/CompilerInvocation.cpp

@@ -638,8 +638,6 @@ static bool parseFrontendArgs(FrontendOptions &opts, llvm::opt::ArgList &args,
   opts.outputFile = args.getLastArgValue(clang::driver::options::OPT_o);
   opts.showHelp = args.hasArg(clang::driver::options::OPT_help);
   opts.showVersion = args.hasArg(clang::driver::options::OPT_version);
-  opts.printSupportedCPUs =
-      args.hasArg(clang::driver::options::OPT_print_supported_cpus);
 
   // Get the input kind (from the value passed via `-x`)
   InputKind dashX(Language::Unknown);

Diff for: flang/test/Driver/print-supported-cpus.f90

@@ -21,35 +21,15 @@
 #include "flang/Frontend/TextDiagnosticBuffer.h"
 #include "flang/FrontendTool/Utils.h"
 #include "clang/Driver/DriverDiagnostic.h"
-#include "llvm/MC/TargetRegistry.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/OptTable.h"
 #include "llvm/Support/TargetSelect.h"
-#include "llvm/Support/raw_ostream.h"
 
 #include <cstdio>
 
 using namespace Fortran::frontend;
 
-/// Print supported cpus of the given target.
-static int printSupportedCPUs(llvm::StringRef triple) {
-  std::string error;
-  const llvm::Target *target =
-      llvm::TargetRegistry::lookupTarget(triple, error);
-  if (!target) {
-    llvm::errs() << error;
-    return 1;
-  }
-
-  // the target machine will handle the mcpu printing
-  llvm::TargetOptions targetOpts;
-  std::unique_ptr<llvm::TargetMachine> targetMachine(
-      target->createTargetMachine(triple, "", "+cpuhelp", targetOpts,
-                                  std::nullopt));
-  return 0;
-}
-
 int fc1_main(llvm::ArrayRef<const char *> argv, const char *argv0) {
   // Create CompilerInstance
   std::unique_ptr<CompilerInstance> flang(new CompilerInstance());
@@ -78,10 +58,6 @@ int fc1_main(llvm::ArrayRef<const char *> argv, const char *argv0) {
   llvm::InitializeAllTargetMCs();
   llvm::InitializeAllAsmPrinters();
 
-  // --print-supported-cpus takes priority over the actual compilation.
-  if (flang->getFrontendOpts().printSupportedCPUs)
-    return printSupportedCPUs(flang->getInvocation().getTargetOpts().triple);
-
   diagsBuffer->flushDiagnostics(flang->getDiagnostics());
 
   if (!success)