Adapt OptTable::PrintHelp change in D51009

[MaskRay]

Summary

Before, OptTable::PrintHelp append "[options] <inputs>" to its parameter Help. It is more flexible to change its semantic to Usage and let user customize the usage line.

[MaskRay]

description

[sbc100]

Since no tests needed updating I guess we not testing much about the output of --help? Should we add some tests?

[ruiu]

Please avoid llvm::formatv because StringRef and Twine work fine as well. I don't expect that the readers of the code memorizes this Python-style format string.

[MaskRay]

In D53054#1261004, @ruiu wrote:

Please avoid llvm::formatv because StringRef and Twine work fine as well. I don't expect that the readers of the code memorizes this Python-style format string.

Sorry, rLLD344212 eliminated another instance of formatv().

COFF/DriverUtils.cpp

 #include "llvm/BinaryFormat/COFF.h"
 #include "llvm/Object/COFF.h"
 #include "llvm/Object/WindowsResource.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/Option.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/WindowsManifest/WindowsManifestMerger.h"
 #include <memory>
 
 using namespace llvm::COFF;

 
 std::vector<const char *> ArgParser::tokenize(StringRef S) {
   SmallVector<const char *, 16> Tokens;
   cl::TokenizeWindowsCommandLine(S, Saver, Tokens);
   return std::vector<const char *>(Tokens.begin(), Tokens.end());
 }
 
 void printHelp(const char *Argv0) {
-  COFFOptTable().PrintHelp(outs(), Argv0, "LLVM Linker", false);
+  std::string Usage = formatv("{0} [options] file...", Argv0).str();
+  COFFOptTable().PrintHelp(outs(), Usage.c_str(), "LLVM Linker", false);
 }
 
 } // namespace coff
 } // namespace lld

ELF/DriverUtils.cpp

 #include "lld/Common/Reproduce.h"
 #include "lld/Common/Version.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Option/Option.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
 
 using namespace llvm;
 using namespace llvm::sys;
 using namespace llvm::opt;
 
 using namespace lld;
if (MissingCount)
     error(Twine(Args.getArgString(MissingIndex)) + ": missing argument");
 
   for (auto *Arg : Args.filtered(OPT_UNKNOWN))
     error("unknown argument: " + Arg->getSpelling());
   return Args;
 }
 
 void elf::printHelp() {
-  ELFOptTable().PrintHelp(outs(), Config->ProgName.data(), "lld",
-                          false /*ShowHidden*/, true /*ShowAllAliases*/);
+  std::string Usage = formatv("{0} [options] file...", Config->ProgName).str();
+  ELFOptTable().PrintHelp(outs(), Usage.c_str(), "lld", false /*ShowHidden*/,
+                          true /*ShowAllAliases*/);
   outs() << "\n";
 
   // Scripts generated by Libtool versions up to at least 2.4.6 (the most
   // recent version as of March 2017) expect /: supported targets:.* elf/
   // in a message for the -help option. If it doesn't match, the scripts
   // assume that the linker doesn't support very basic features such as
   // shared libraries. Therefore, we need to print out at least "elf".
   outs() << Config->ProgName << ": supported targets: elf\n";

lib/Driver/DarwinLdDriver.cpp

 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/OptTable.h"
 #include "llvm/Option/Option.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/Format.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 #include <cstdint>
 #include <memory>
 #include <string>
for (auto &inFile : parsedArgs.filtered(OPT_INPUT)) {
       // This is expensive because it opens and maps the file.  But that is
       // ok because no -arch is rare.
       if (MachOLinkingContext::isThinObjectFile(inFile->getValue(), arch))
         break;
     }
     if (arch == MachOLinkingContext::arch_unknown &&
         !parsedArgs.getLastArg(OPT_test_file_usage)) {
       // If no -arch and no options at all, print usage message.
-      if (parsedArgs.size() == 0)
-        table.PrintHelp(llvm::outs(), args[0], "LLVM Linker", false);
-      else
+      if (parsedArgs.size() == 0) {
+        std::string Usage =
+            llvm::formatv("{0} [options] file...", args[0]).str();
+        table.PrintHelp(llvm::outs(), Usage.c_str(), "LLVM Linker", false);
+      } else {
         error("-arch not specified and could not be inferred");
+      }
       return false;
     }
   }
 
   // Handle -macosx_version_min or -ios_version_min
   MachOLinkingContext::OS os = MachOLinkingContext::OS::unknown;
   uint32_t minOSVersion = 0;
   if (llvm::opt::Arg *minOS =

wasm/Driver.cpp

 #include "lld/Common/Memory.h"
 #include "lld/Common/Strings.h"
 #include "lld/Common/Threads.h"
 #include "lld/Common/Version.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Object/Wasm.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/TargetSelect.h"
 
 #define DEBUG_TYPE "lld"
 
 using namespace llvm;
 using namespace llvm::sys;

 }
 
 void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
   WasmOptTable Parser;
   opt::InputArgList Args = Parser.parse(ArgsArr.slice(1));
 
   // Handle --help
   if (Args.hasArg(OPT_help)) {
-    Parser.PrintHelp(outs(), ArgsArr[0], "LLVM Linker", false);
+    std::string Usage = formatv("{0} [options] file...", ArgsArr[0]).str();
+    Parser.PrintHelp(outs(), Usage.c_str(), "LLVM Linker", false);
     return;
   }
 
   // Handle --version
   if (Args.hasArg(OPT_version) || Args.hasArg(OPT_v)) {
     outs() << getLLDVersion() << "\n";
     return;
   }