COFF: Create LinkerDriver class.

Previously the main linker routine is just a non-member function.
We store some context information to the Config object.
This patch makes it belong to Driver.

llvm-svn: 238677

lld/COFF/Config.h

@@ -37,13 +37,6 @@ public:
   uint32_t MinorImageVersion = 0;
   uint32_t MajorOSVersion = 6;
   uint32_t MinorOSVersion = 0;
-
-  bool insertFile(llvm::StringRef Path) {
-    return VisitedFiles.insert(Path.lower()).second;
-  }
-
-private:
-  std::set<std::string> VisitedFiles;
 };
 
 extern Configuration *Config;

lld/COFF/Driver.cpp

@@ -35,6 +35,15 @@ namespace lld {
 namespace coff {
 
 Configuration *Config;
+LinkerDriver *Driver;
+
+bool link(int Argc, const char *Argv[]) {
+  auto C = make_unique<Configuration>();
+  Config = C.get();
+  auto D = make_unique<LinkerDriver>();
+  Driver = D.get();
+  return Driver->link(Argc, Argv);
+}
 
 static std::string getOutputPath(llvm::opt::InputArgList *Args) {
   if (auto *Arg = Args->getLastArg(OPT_out))
@@ -68,12 +77,12 @@ public:
 
 // Parses .drectve section contents and returns a list of files
 // specified by /defaultlib.
-std::error_code parseDirectives(StringRef S,
-                                std::vector<std::unique_ptr<InputFile>> *Res,
-                                StringAllocator *Alloc) {
+std::error_code
+LinkerDriver::parseDirectives(StringRef S,
+                              std::vector<std::unique_ptr<InputFile>> *Res) {
   SmallVector<const char *, 16> Tokens;
   Tokens.push_back("link"); // argv[0] value. Will be ignored.
-  BumpPtrStringSaver Saver(Alloc);
+  BumpPtrStringSaver Saver(&Alloc);
   llvm::cl::TokenizeWindowsCommandLine(S, Saver, Tokens);
   Tokens.push_back(nullptr);
   int Argc = Tokens.size() - 1;
@@ -86,16 +95,15 @@ std::error_code parseDirectives(StringRef S,
 
   for (auto *Arg : Args->filtered(OPT_defaultlib)) {
     std::string Path = findLib(Arg->getValue());
-    if (!Config->insertFile(Path))
+    if (!insertFile(Path))
       continue;
     Res->push_back(llvm::make_unique<ArchiveFile>(Path));
   }
   return std::error_code();
 }
 
-bool link(int Argc, const char *Argv[]) {
+bool LinkerDriver::link(int Argc, const char *Argv[]) {
   // Parse command line options.
-  Config = new Configuration();
   auto ArgsOrErr = parseArgs(Argc, Argv);
   if (auto EC = ArgsOrErr.getError()) {
     llvm::errs() << EC.message() << "\n";
@@ -180,7 +188,7 @@ bool link(int Argc, const char *Argv[]) {
   SymbolTable Symtab;
   for (auto *Arg : Args->filtered(OPT_INPUT)) {
     std::string Path = findFile(Arg->getValue());
-    if (!Config->insertFile(Path))
+    if (!insertFile(Path))
       continue;
     if (auto EC = Symtab.addFile(createFile(Path))) {
       llvm::errs() << Path << ": " << EC.message() << "\n";
@@ -229,5 +237,9 @@ bool link(int Argc, const char *Argv[]) {
   return true;
 }
 
+bool LinkerDriver::insertFile(StringRef Path) {
+  return VisitedFiles.insert(Path.lower()).second;
+}
+
 } // namespace coff
 } // namespace lld

lld/COFF/Driver.h

@@ -16,23 +16,42 @@
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include <memory>
+#include <set>
 #include <system_error>
 #include <vector>
 
 namespace lld {
 namespace coff {
 
+class LinkerDriver;
+extern LinkerDriver *Driver;
+
 using llvm::COFF::MachineTypes;
 using llvm::COFF::WindowsSubsystem;
 class InputFile;
 
+// Entry point of the COFF linker.
+bool link(int Argc, const char *Argv[]);
+
+class LinkerDriver {
+public:
+  bool link(int Argc, const char *Argv[]);
+
+  // Used by the resolver to parse .drectve section contents.
+  std::error_code
+  parseDirectives(StringRef S, std::vector<std::unique_ptr<InputFile>> *Res);
+
+private:
+  // Returns false if a given file has already been read.
+  bool insertFile(StringRef Path);
+
+  std::set<std::string> VisitedFiles;
+  StringAllocator Alloc;
+};
+
 ErrorOr<std::unique_ptr<llvm::opt::InputArgList>>
 parseArgs(int Argc, const char *Argv[]);
 
-std::error_code parseDirectives(StringRef S,
-                                std::vector<std::unique_ptr<InputFile>> *Res,
-                                StringAllocator *Alloc);
-
 // Functions below this line are defined in DriverUtils.cpp.
 
 void printHelp(const char *Argv0);

lld/COFF/SymbolTable.cpp

@@ -49,7 +49,7 @@ std::error_code SymbolTable::addObject(ObjectFile *File) {
   StringRef Dir = File->getDirectives();
   if (!Dir.empty()) {
     std::vector<std::unique_ptr<InputFile>> Libs;
-    if (auto EC = parseDirectives(Dir, &Libs, &StringAlloc))
+    if (auto EC = Driver->parseDirectives(Dir, &Libs))
       return EC;
     for (std::unique_ptr<InputFile> &Lib : Libs)
       addFile(std::move(Lib));

lld/COFF/SymbolTable.h

@@ -78,7 +78,6 @@ private:
   std::vector<std::unique_ptr<ArchiveFile>> ArchiveFiles;
   std::vector<std::unique_ptr<SymbolBody>> OwningSymbols;
   llvm::BumpPtrAllocator Alloc;
-  StringAllocator StringAlloc;
 };
 
 } // namespace pecoff