1 //===-- llvm-modextract.cpp - LLVM module extractor utility ---------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This program is for testing features that rely on multi-module bitcode files.
10 // It takes a multi-module bitcode file, extracts one of the modules and writes
11 // it to the output file.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Bitcode/BitcodeReader.h"
16 #include "llvm/Bitcode/BitcodeWriter.h"
17 #include "llvm/Support/CommandLine.h"
18 #include "llvm/Support/Error.h"
19 #include "llvm/Support/FileSystem.h"
20 #include "llvm/Support/ToolOutputFile.h"
25 BinaryExtract("b", cl::desc("Whether to perform binary extraction"));
27 static cl::opt<std::string> OutputFilename("o", cl::Required,
28 cl::desc("Output filename"),
29 cl::value_desc("filename"));
31 static cl::opt<std::string>
32 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
34 static cl::opt<unsigned> ModuleIndex("n", cl::Required,
35 cl::desc("Index of module to extract"),
36 cl::value_desc("index"));
38 int main(int argc, char **argv) {
39 cl::ParseCommandLineOptions(argc, argv, "Module extractor");
41 ExitOnError ExitOnErr("llvm-modextract: error: ");
43 std::unique_ptr<MemoryBuffer> MB =
44 ExitOnErr(errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename)));
45 std::vector<BitcodeModule> Ms = ExitOnErr(getBitcodeModuleList(*MB));
48 if (ModuleIndex >= Ms.size()) {
49 errs() << "llvm-modextract: error: module index out of range; bitcode file "
51 << Ms.size() << " module(s)\n";
56 std::unique_ptr<ToolOutputFile> Out(
57 new ToolOutputFile(OutputFilename, EC, sys::fs::F_None));
58 ExitOnErr(errorCodeToError(EC));
61 SmallVector<char, 0> Result;
62 BitcodeWriter Writer(Result);
63 Result.append(Ms[ModuleIndex].getBuffer().begin(),
64 Ms[ModuleIndex].getBuffer().end());
65 Writer.copyStrtab(Ms[ModuleIndex].getStrtab());
71 std::unique_ptr<Module> M = ExitOnErr(Ms[ModuleIndex].parseModule(Context));
72 WriteBitcodeToFile(*M, Out->os());