LibDriver, llvm-lib: introduce.

llvm-lib is intended to be a lib.exe compatible utility that also
understands bitcode. The implementation lives in a library so that
lld can use it to implement /lib.

Differential Revision: http://reviews.llvm.org/D10297

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239434 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 200 insertions, 0 deletions

diff --git a/lib/LibDriver/CMakeLists.txt b/lib/LibDriver/CMakeLists.txt
new file mode 100644
index 000000000000..ab53a6843446
--- /dev/null
+++ b/lib/LibDriver/CMakeLists.txt
@@ -0,0 +1,8 @@
+set(LLVM_TARGET_DEFINITIONS Options.td)
+tablegen(LLVM Options.inc -gen-opt-parser-defs)
+add_public_tablegen_target(LibOptionsTableGen)
+
+add_llvm_library(LLVMLibDriver
+  LibDriver.cpp
+  )
+add_dependencies(LLVMLibDriver LibOptionsTableGen)
diff --git a/lib/LibDriver/LLVMBuild.txt b/lib/LibDriver/LLVMBuild.txt
new file mode 100644
index 000000000000..799dc997c0bb
--- /dev/null
+++ b/lib/LibDriver/LLVMBuild.txt
@@ -0,0 +1,22 @@
+;===- ./lib/LibDriver/LLVMBuild.txt ----------------------------*- Conf -*--===;
+;
+;                     The LLVM Compiler Infrastructure
+;
+; This file is distributed under the University of Illinois Open Source
+; License. See LICENSE.TXT for details.
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[component_0]
+type = Library
+name = LibDriver
+parent = Libraries
+required_libraries = Object Option Support
diff --git a/lib/LibDriver/LibDriver.cpp b/lib/LibDriver/LibDriver.cpp
new file mode 100644
index 000000000000..d028e4bbca54
--- /dev/null
+++ b/lib/LibDriver/LibDriver.cpp
@@ -0,0 +1,133 @@
+//===- LibDriver.cpp - lib.exe-compatible driver --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Defines an interface to a lib.exe-compatible driver that also understands
+// bitcode files. Used by llvm-lib and lld-link2 /lib.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/LibDriver/LibDriver.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Object/ArchiveWriter.h"
+#include "llvm/Option/Arg.h"
+#include "llvm/Option/ArgList.h"
+#include "llvm/Option/Option.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+namespace {
+
+enum {
+  OPT_INVALID = 0,
+#define OPTION(_1, _2, ID, _4, _5, _6, _7, _8, _9, _10, _11) OPT_##ID,
+#include "Options.inc"
+#undef OPTION
+};
+
+#define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
+#include "Options.inc"
+#undef PREFIX
+
+static const llvm::opt::OptTable::Info infoTable[] = {
+#define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X6, X7, X8, X9, X10)    \
+  {                                                                    \
+    X1, X2, X9, X10, OPT_##ID, llvm::opt::Option::KIND##Class, X8, X7, \
+    OPT_##GROUP, OPT_##ALIAS, X6                                       \
+  },
+#include "Options.inc"
+#undef OPTION
+};
+
+class LibOptTable : public llvm::opt::OptTable {
+public:
+  LibOptTable() : OptTable(infoTable, llvm::array_lengthof(infoTable), true) {}
+};
+
+}
+
+static std::string getOutputPath(llvm::opt::InputArgList *Args) {
+  if (auto *Arg = Args->getLastArg(OPT_out))
+    return Arg->getValue();
+  for (auto *Arg : Args->filtered(OPT_INPUT)) {
+    if (!StringRef(Arg->getValue()).endswith_lower(".obj"))
+      continue;
+    SmallString<128> Val = StringRef(Arg->getValue());
+    llvm::sys::path::replace_extension(Val, ".lib");
+    return Val.str();
+  }
+  llvm_unreachable("internal error");
+}
+
+namespace {
+// FIXME: Should re-use StringSaver from lld.
+class StrDupSaver : public cl::StringSaver {
+  std::vector<char *> Dups;
+
+public:
+  ~StrDupSaver() override {
+    for (std::vector<char *>::iterator I = Dups.begin(), E = Dups.end(); I != E;
+         ++I) {
+      char *Dup = *I;
+      free(Dup);
+    }
+  }
+  const char *SaveString(const char *Str) override {
+    char *Dup = strdup(Str);
+    Dups.push_back(Dup);
+    return Dup;
+  }
+};
+}
+
+int llvm::libDriverMain(int Argc, const char **Argv) {
+  SmallVector<const char *, 20> NewArgv(Argv, Argv + Argc);
+  StrDupSaver Saver;
+  cl::ExpandResponseFiles(Saver, cl::TokenizeWindowsCommandLine, NewArgv);
+  Argv = &NewArgv[0];
+  Argc = static_cast<int>(NewArgv.size());
+
+  LibOptTable Table;
+  unsigned MissingIndex;
+  unsigned MissingCount;
+  std::unique_ptr<llvm::opt::InputArgList> Args(
+      Table.ParseArgs(&Argv[1], &Argv[Argc], MissingIndex, MissingCount));
+  if (MissingCount) {
+    llvm::errs() << "missing arg value for \""
+                 << Args->getArgString(MissingIndex)
+                 << "\", expected " << MissingCount
+                 << (MissingCount == 1 ? " argument.\n" : " arguments.\n");
+    return 1;
+  }
+  for (auto *Arg : Args->filtered(OPT_UNKNOWN))
+    llvm::errs() << "ignoring unknown argument: " << Arg->getSpelling() << "\n";
+
+  if (Args->filtered_begin(OPT_INPUT) == Args->filtered_end()) {
+    llvm::errs() << "no input files.\n";
+    return 1;
+  }
+
+  std::vector<llvm::NewArchiveIterator> Members;
+  for (auto *Arg : Args->filtered(OPT_INPUT))
+    Members.emplace_back(Arg->getValue(),
+                         llvm::sys::path::filename(Arg->getValue()));
+
+  std::pair<StringRef, std::error_code> Result = llvm::writeArchive(
+      getOutputPath(Args.get()), Members, /*WriteSymtab=*/true);
+  if (Result.second) {
+    if (Result.first.empty())
+      Result.first = Argv[0];
+    llvm::errs() << Result.first << ": " << Result.second.message() << "\n";
+    return 1;
+  }
+
+  return 0;
+}
diff --git a/lib/LibDriver/Makefile b/lib/LibDriver/Makefile
new file mode 100644
index 000000000000..1c62eac9093d
--- /dev/null
+++ b/lib/LibDriver/Makefile
@@ -0,0 +1,20 @@
+##===- lib/LibDriver/Makefile ------------------------------*- Makefile -*-===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+LEVEL = ../..
+LIBRARYNAME = LLVMLibDriver
+BUILD_ARCHIVE := 1
+BUILT_SOURCES = Options.inc
+TABLEGEN_INC_FILES_COMMON = 1
+
+include $(LEVEL)/Makefile.common
+
+$(ObjDir)/Options.inc.tmp : Options.td $(LLVM_TBLGEN) $(ObjDir)/.dir
+	$(Echo) "Building lib Driver Option tables with tblgen"
+	$(Verb) $(LLVMTableGen) -gen-opt-parser-defs -o $(call SYSPATH, $@) $<
diff --git a/lib/LibDriver/Options.td b/lib/LibDriver/Options.td
new file mode 100644
index 000000000000..0db84bcffb76
--- /dev/null
+++ b/lib/LibDriver/Options.td
@@ -0,0 +1,17 @@
+include "llvm/Option/OptParser.td"
+
+// lib.exe accepts options starting with either a dash or a slash.
+
+// Flag that takes no arguments.
+class F<string name> : Flag<["/", "-", "-?"], name>;
+
+// Flag that takes one argument after ":".
+class P<string name, string help> :
+      Joined<["/", "-", "-?"], name#":">, HelpText<help>;
+
+def out    : P<"out", "Path to file to write output">;
+
+//==============================================================================
+// The flags below do nothing. They are defined only for lib.exe compatibility.
+//==============================================================================
+def nologo : F<"nologo">;