llvm-project/llvm/tools/llvm-modextract/llvm-modextract.cpp

87 lines
3.2 KiB
C++

//===-- llvm-modextract.cpp - LLVM module extractor utility ---------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This program is for testing features that rely on multi-module bitcode files.
// It takes a multi-module bitcode file, extracts one of the modules and writes
// it to the output file.
//
//===----------------------------------------------------------------------===//
#include "llvm/Bitcode/BitcodeReader.h"
#include "llvm/Bitcode/BitcodeWriter.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Support/WithColor.h"
using namespace llvm;
static cl::OptionCategory ModextractCategory("Modextract Options");
static cl::opt<bool>
BinaryExtract("b", cl::desc("Whether to perform binary extraction"),
cl::cat(ModextractCategory));
static cl::opt<std::string> OutputFilename("o", cl::Required,
cl::desc("Output filename"),
cl::value_desc("filename"),
cl::cat(ModextractCategory));
static cl::opt<std::string> InputFilename(cl::Positional,
cl::desc("<input bitcode>"),
cl::init("-"),
cl::cat(ModextractCategory));
static cl::opt<unsigned> ModuleIndex("n", cl::Required,
cl::desc("Index of module to extract"),
cl::value_desc("index"),
cl::cat(ModextractCategory));
int main(int argc, char **argv) {
cl::HideUnrelatedOptions({&ModextractCategory, &getColorCategory()});
cl::ParseCommandLineOptions(argc, argv, "Module extractor");
ExitOnError ExitOnErr("llvm-modextract: error: ");
std::unique_ptr<MemoryBuffer> MB =
ExitOnErr(errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename)));
std::vector<BitcodeModule> Ms = ExitOnErr(getBitcodeModuleList(*MB));
LLVMContext Context;
if (ModuleIndex >= Ms.size()) {
errs() << "llvm-modextract: error: module index out of range; bitcode file "
"contains "
<< Ms.size() << " module(s)\n";
return 1;
}
std::error_code EC;
std::unique_ptr<ToolOutputFile> Out(
new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None));
ExitOnErr(errorCodeToError(EC));
if (BinaryExtract) {
SmallVector<char, 0> Result;
BitcodeWriter Writer(Result);
Result.append(Ms[ModuleIndex].getBuffer().begin(),
Ms[ModuleIndex].getBuffer().end());
Writer.copyStrtab(Ms[ModuleIndex].getStrtab());
Out->os() << Result;
Out->keep();
return 0;
}
std::unique_ptr<Module> M = ExitOnErr(Ms[ModuleIndex].parseModule(Context));
WriteBitcodeToFile(*M, Out->os());
Out->keep();
return 0;
}