[ELF] Make Ctx inherit from CommonLinkerContext

link calls `new CommonLinkerContext`. Now that `Ctx ctx` is a local
variable, we can make it inherit from CommonLinkerContext.

Author: MaskRay

lld/ELF/Config.h

@@ -551,15 +551,12 @@ struct InStruct {
   std::unique_ptr<SymtabShndxSection> symTabShndx;
 };
 
-struct Ctx {
+struct Ctx : CommonLinkerContext {
   Config arg;
   LinkerDriver driver;
   LinkerScript *script;
   std::unique_ptr<TargetInfo> target;
 
-  CommonLinkerContext *commonCtx;
-  ErrorHandler *errHandler;
-
   // These variables are initialized by Writer and should not be used before
   // Writer is initialized.
   uint8_t *bufferStart = nullptr;
@@ -689,18 +686,16 @@ static inline ArrayRef<VersionDefinition> namedVersionDefs(Ctx &ctx) {
   return llvm::ArrayRef(ctx.arg.versionDefinitions).slice(2);
 }
 
-inline llvm::BumpPtrAllocator &bAlloc(Ctx &ctx) {
-  return ctx.commonCtx->bAlloc;
-}
-inline llvm::StringSaver &saver(Ctx &ctx) { return ctx.commonCtx->saver; }
+inline llvm::BumpPtrAllocator &bAlloc(Ctx &ctx) { return ctx.bAlloc; }
+inline llvm::StringSaver &saver(Ctx &ctx) { return ctx.saver; }
 inline llvm::UniqueStringSaver &uniqueSaver(Ctx &ctx) {
-  return ctx.commonCtx->uniqueSaver;
+  return ctx.uniqueSaver;
 }
 
 struct ELFSyncStream : SyncStream {
   Ctx &ctx;
   ELFSyncStream(Ctx &ctx, DiagLevel level)
-      : SyncStream(*ctx.errHandler, level), ctx(ctx) {}
+      : SyncStream(ctx.e, level), ctx(ctx) {}
 };
 
 template <typename T>

lld/ELF/Driver.cpp

@@ -90,7 +90,7 @@ ELFSyncStream elf::Err(Ctx &ctx) {
 }
 ELFSyncStream elf::ErrAlways(Ctx &ctx) { return {ctx, DiagLevel::Err}; }
 ELFSyncStream elf::Fatal(Ctx &ctx) { return {ctx, DiagLevel::Fatal}; }
-uint64_t elf::errCount(Ctx &ctx) { return ctx.errHandler->errorCount; }
+uint64_t elf::errCount(Ctx &ctx) { return ctx.e.errorCount; }
 
 ELFSyncStream elf::InternalErr(Ctx &ctx, const uint8_t *buf) {
   ELFSyncStream s(ctx, DiagLevel::Err);
@@ -112,9 +112,9 @@ namespace lld {
 namespace elf {
 bool link(ArrayRef<const char *> args, llvm::raw_ostream &stdoutOS,
           llvm::raw_ostream &stderrOS, bool exitEarly, bool disableOutput) {
-  Ctx ctx;
   // This driver-specific context will be freed later by unsafeLldMain().
-  auto *context = new CommonLinkerContext;
+  auto *context = new Ctx;
+  Ctx &ctx = *context;
 
   context->e.initialize(stdoutOS, stderrOS, exitEarly, disableOutput);
   context->e.logName = args::getFilenameWithoutExe(args[0]);
@@ -124,8 +124,6 @@ bool link(ArrayRef<const char *> args, llvm::raw_ostream &stdoutOS,
 
   LinkerScript script(ctx);
   ctx.script = &script;
-  ctx.commonCtx = context;
-  ctx.errHandler = &context->e;
   ctx.symAux.emplace_back();
   ctx.symtab = std::make_unique<SymbolTable>(ctx);
 
@@ -334,8 +332,8 @@ void LinkerDriver::addLibrary(StringRef name) {
   if (std::optional<std::string> path = searchLibrary(ctx, name))
     addFile(saver(ctx).save(*path), /*withLOption=*/true);
   else
-    ctx.errHandler->error("unable to find library -l" + name,
-                          ErrorTag::LibNotFound, {name});
+    ctx.e.error("unable to find library -l" + name, ErrorTag::LibNotFound,
+                {name});
 }
 
 // This function is called on startup. We need this for LTO since
@@ -589,11 +587,11 @@ void LinkerDriver::linkerMain(ArrayRef<const char *> argsArr) {
   opt::InputArgList args = parser.parse(ctx, argsArr.slice(1));
 
   // Interpret these flags early because Err/Warn depend on them.
-  ctx.errHandler->errorLimit = args::getInteger(args, OPT_error_limit, 20);
-  ctx.errHandler->fatalWarnings =
+  ctx.e.errorLimit = args::getInteger(args, OPT_error_limit, 20);
+  ctx.e.fatalWarnings =
       args.hasFlag(OPT_fatal_warnings, OPT_no_fatal_warnings, false) &&
       !args.hasArg(OPT_no_warnings);
-  ctx.errHandler->suppressWarnings = args.hasArg(OPT_no_warnings);
+  ctx.e.suppressWarnings = args.hasArg(OPT_no_warnings);
 
   // Handle -help
   if (args.hasArg(OPT_help)) {
@@ -667,10 +665,9 @@ void LinkerDriver::linkerMain(ArrayRef<const char *> argsArr) {
   }
 
   if (ctx.arg.timeTraceEnabled) {
-    checkError(
-        *ctx.errHandler,
-        timeTraceProfilerWrite(args.getLastArgValue(OPT_time_trace_eq).str(),
-                               ctx.arg.outputFile));
+    checkError(ctx.e, timeTraceProfilerWrite(
+                          args.getLastArgValue(OPT_time_trace_eq).str(),
+                          ctx.arg.outputFile));
     timeTraceProfilerCleanup();
   }
 }
@@ -1227,8 +1224,8 @@ static bool remapInputs(Ctx &ctx, StringRef line, const Twine &location) {
 
 // Initializes Config members by the command line options.
 static void readConfigs(Ctx &ctx, opt::InputArgList &args) {
-  ctx.errHandler->verbose = args.hasArg(OPT_verbose);
-  ctx.errHandler->vsDiagnostics =
+  ctx.e.verbose = args.hasArg(OPT_verbose);
+  ctx.e.vsDiagnostics =
       args.hasArg(OPT_visual_studio_diagnostics_format, false);
 
   ctx.arg.allowMultipleDefinition =
@@ -1286,8 +1283,7 @@ static void readConfigs(Ctx &ctx, opt::InputArgList &args) {
       args.hasArg(OPT_enable_non_contiguous_regions);
   ctx.arg.entry = args.getLastArgValue(OPT_entry);
 
-  ctx.errHandler->errorHandlingScript =
-      args.getLastArgValue(OPT_error_handling_script);
+  ctx.e.errorHandlingScript = args.getLastArgValue(OPT_error_handling_script);
 
   ctx.arg.executeOnly =
       args.hasFlag(OPT_execute_only, OPT_no_execute_only, false);

lld/ELF/DriverUtils.cpp

@@ -58,9 +58,9 @@ static void handleColorDiagnostics(Ctx &ctx, opt::InputArgList &args) {
     return;
   StringRef s = arg->getValue();
   if (s == "always")
-    ctx.errHandler->errs().enable_colors(true);
+    ctx.e.errs().enable_colors(true);
   else if (s == "never")
-    ctx.errHandler->errs().enable_colors(false);
+    ctx.e.errs().enable_colors(false);
   else if (s != "auto")
     ErrAlways(ctx) << "unknown option: --color-diagnostics=" << s;
 }
@@ -138,7 +138,7 @@ opt::InputArgList ELFOptTable::parse(Ctx &ctx, ArrayRef<const char *> argv) {
 }
 
 void elf::printHelp(Ctx &ctx) {
-  auto &outs = ctx.errHandler->outs();
+  auto &outs = ctx.e.outs();
   ELFOptTable().printHelp(
       outs, (ctx.arg.progName + " [options] file...").str().c_str(), "lld",
       false /*ShowHidden*/, true /*ShowAllAliases*/);

lld/ELF/LTO.cpp

@@ -165,9 +165,9 @@ static lto::Config createConfig(Ctx &ctx) {
   }
 
   if (!ctx.arg.saveTempsArgs.empty())
-    checkError(*ctx.errHandler, c.addSaveTemps(ctx.arg.outputFile.str() + ".",
-                                               /*UseInputModulePath*/ true,
-                                               ctx.arg.saveTempsArgs));
+    checkError(ctx.e, c.addSaveTemps(ctx.arg.outputFile.str() + ".",
+                                     /*UseInputModulePath*/ true,
+                                     ctx.arg.saveTempsArgs));
   return c;
 }
 
@@ -278,7 +278,7 @@ void BitcodeCompiler::add(BitcodeFile &f) {
     // their values are still not final.
     r.LinkerRedefined = sym->scriptDefined;
   }
-  checkError(*ctx.errHandler, ltoObj->add(std::move(f.obj), resols));
+  checkError(ctx.e, ltoObj->add(std::move(f.obj), resols));
 }
 
 // If LazyObjFile has not been added to link, emit empty index files.
@@ -329,14 +329,14 @@ std::vector<InputFile *> BitcodeCompiler::compile() {
                              }));
 
   if (!ctx.bitcodeFiles.empty())
-    checkError(*ctx.errHandler, ltoObj->run(
-                                    [&](size_t task, const Twine &moduleName) {
-                                      buf[task].first = moduleName.str();
-                                      return std::make_unique<CachedFileStream>(
-                                          std::make_unique<raw_svector_ostream>(
-                                              buf[task].second));
-                                    },
-                                    cache));
+    checkError(ctx.e, ltoObj->run(
+                          [&](size_t task, const Twine &moduleName) {
+                            buf[task].first = moduleName.str();
+                            return std::make_unique<CachedFileStream>(
+                                std::make_unique<raw_svector_ostream>(
+                                    buf[task].second));
+                          },
+                          cache));
 
   // Emit empty index files for non-indexed files but not in single-module mode.
   if (ctx.arg.thinLTOModulesToCompile.empty()) {

lld/ELF/Relocations.cpp

@@ -777,7 +777,7 @@ static void reportUndefinedSymbol(Ctx &ctx, const UndefinedDiag &undef,
   if (undef.isWarning)
     Warn(ctx) << msg;
   else
-    ctx.errHandler->error(msg, ErrorTag::SymbolNotFound, {sym.getName()});
+    ctx.e.error(msg, ErrorTag::SymbolNotFound, {sym.getName()});
 }
 
 void elf::reportUndefinedSymbols(Ctx &ctx) {

lld/ELF/Writer.cpp

@@ -49,7 +49,7 @@ template <class ELFT> class Writer {
 public:
   LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
 
-  Writer(Ctx &ctx) : ctx(ctx), buffer(ctx.errHandler->outputBuffer) {}
+  Writer(Ctx &ctx) : ctx(ctx), buffer(ctx.e.outputBuffer) {}
 
   void run();
 
@@ -342,7 +342,7 @@ template <class ELFT> void Writer<ELFT>::run() {
 
   // Handle --print-memory-usage option.
   if (ctx.arg.printMemoryUsage)
-    ctx.script->printMemoryUsage(ctx.errHandler->outs());
+    ctx.script->printMemoryUsage(ctx.e.outs());
 
   if (ctx.arg.checkSections)
     checkSections();