llvm-6502/tools/dsymutil/dsymutil.cpp
Frederic Riss 309fcf84b8 [dsymutil] Implement ODR uniquing for C++ code.
This optimization allows the DWARF linker to reuse definition of
types it has emitted in previous CUs rather than reemitting them
in each CU that references them. The size and link time gains are
huge. For example when linking the DWARF for a debug build of
clang, this generates a ~150M dwarf file instead of a ~700M one
(the numbers date back a bit and must not be totally accurate
these days).

As with all the other parts of the llvm-dsymutil codebase, the
goal is to keep bit-for-bit compatibility with dsymutil-classic.
The code is littered with a lot of FIXMEs that should be
addressed once we can get rid of the compatibilty goal.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242847 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-21 22:41:43 +00:00

110 lines
3.1 KiB
C++

//===-- dsymutil.cpp - Debug info dumping utility for llvm ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This program is a utility that aims to be a dropin replacement for
// Darwin's dsymutil.
//
//===----------------------------------------------------------------------===//
#include "DebugMap.h"
#include "dsymutil.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/Options.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/Signals.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/TargetSelect.h"
#include <string>
using namespace llvm::dsymutil;
namespace {
using namespace llvm::cl;
static opt<std::string> InputFile(Positional, desc("<input file>"),
init("a.out"));
static opt<std::string>
OutputFileOpt("o",
desc("Specify the output file. default: <input file>.dwarf"),
value_desc("filename"));
static opt<std::string> OsoPrependPath(
"oso-prepend-path",
desc("Specify a directory to prepend to the paths of object files."),
value_desc("path"));
static opt<bool> Verbose("v", desc("Verbosity level"), init(false));
static opt<bool>
NoOutput("no-output",
desc("Do the link in memory, but do not emit the result file."),
init(false));
static opt<bool>
NoODR("no-odr",
desc("Do not use ODR (One Definition Rule) for type uniquing."),
init(false));
static opt<bool> DumpDebugMap(
"dump-debug-map",
desc("Parse and dump the debug map to standard output. Not DWARF link "
"will take place."),
init(false));
static opt<bool> InputIsYAMLDebugMap(
"y", desc("Treat the input file is a YAML debug map rather than a binary."),
init(false));
}
int main(int argc, char **argv) {
llvm::sys::PrintStackTraceOnErrorSignal();
llvm::PrettyStackTraceProgram StackPrinter(argc, argv);
llvm::llvm_shutdown_obj Shutdown;
LinkOptions Options;
llvm::cl::ParseCommandLineOptions(argc, argv, "llvm dsymutil\n");
auto DebugMapPtrOrErr =
parseDebugMap(InputFile, OsoPrependPath, Verbose, InputIsYAMLDebugMap);
Options.Verbose = Verbose;
Options.NoOutput = NoOutput;
Options.NoODR = NoODR;
llvm::InitializeAllTargetInfos();
llvm::InitializeAllTargetMCs();
llvm::InitializeAllTargets();
llvm::InitializeAllAsmPrinters();
if (auto EC = DebugMapPtrOrErr.getError()) {
llvm::errs() << "error: cannot parse the debug map for \"" << InputFile
<< "\": " << EC.message() << '\n';
return 1;
}
if (Verbose || DumpDebugMap)
(*DebugMapPtrOrErr)->print(llvm::outs());
if (DumpDebugMap)
return 0;
std::string OutputFile;
if (OutputFileOpt.empty()) {
if (InputFile == "-")
OutputFile = "a.out.dwarf";
else
OutputFile = InputFile + ".dwarf";
} else {
OutputFile = OutputFileOpt;
}
return !linkDwarf(OutputFile, **DebugMapPtrOrErr, Options);
}