1 //===-- llvm-modextract.cpp - LLVM module extractor utility ---------------===// 2 // 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 6 // 7 //===----------------------------------------------------------------------===// 8 // 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. 12 // 13 //===----------------------------------------------------------------------===// 14 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" 21 22 using namespace llvm; 23 24 static cl::opt<bool> 25 BinaryExtract("b", cl::desc("Whether to perform binary extraction")); 26 27 static cl::opt<std::string> OutputFilename("o", cl::Required, 28 cl::desc("Output filename"), 29 cl::value_desc("filename")); 30 31 static cl::opt<std::string> 32 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-")); 33 34 static cl::opt<unsigned> ModuleIndex("n", cl::Required, 35 cl::desc("Index of module to extract"), 36 cl::value_desc("index")); 37 38 int main(int argc, char **argv) { 39 cl::ParseCommandLineOptions(argc, argv, "Module extractor"); 40 41 ExitOnError ExitOnErr("llvm-modextract: error: "); 42 43 std::unique_ptr<MemoryBuffer> MB = 44 ExitOnErr(errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename))); 45 std::vector<BitcodeModule> Ms = ExitOnErr(getBitcodeModuleList(*MB)); 46 47 LLVMContext Context; 48 if (ModuleIndex >= Ms.size()) { 49 errs() << "llvm-modextract: error: module index out of range; bitcode file " 50 "contains " 51 << Ms.size() << " module(s)\n"; 52 return 1; 53 } 54 55 std::error_code EC; 56 std::unique_ptr<ToolOutputFile> Out( 57 new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None)); 58 ExitOnErr(errorCodeToError(EC)); 59 60 if (BinaryExtract) { 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()); 66 Out->os() << Result; 67 Out->keep(); 68 return 0; 69 } 70 71 std::unique_ptr<Module> M = ExitOnErr(Ms[ModuleIndex].parseModule(Context)); 72 WriteBitcodeToFile(*M, Out->os()); 73 74 Out->keep(); 75 return 0; 76 } 77