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 #include "llvm/Support/WithColor.h" 22 23 using namespace llvm; 24 25 static cl::OptionCategory ModextractCategory("Modextract Options"); 26 27 static cl::opt<bool> 28 BinaryExtract("b", cl::desc("Whether to perform binary extraction"), 29 cl::cat(ModextractCategory)); 30 31 static cl::opt<std::string> OutputFilename("o", cl::Required, 32 cl::desc("Output filename"), 33 cl::value_desc("filename"), 34 cl::cat(ModextractCategory)); 35 36 static cl::opt<std::string> InputFilename(cl::Positional, 37 cl::desc("<input bitcode>"), 38 cl::init("-"), 39 cl::cat(ModextractCategory)); 40 41 static cl::opt<unsigned> ModuleIndex("n", cl::Required, 42 cl::desc("Index of module to extract"), 43 cl::value_desc("index"), 44 cl::cat(ModextractCategory)); 45 46 int main(int argc, char **argv) { 47 cl::HideUnrelatedOptions({&ModextractCategory, &getColorCategory()}); 48 cl::ParseCommandLineOptions(argc, argv, "Module extractor"); 49 50 ExitOnError ExitOnErr("llvm-modextract: error: "); 51 52 std::unique_ptr<MemoryBuffer> MB = 53 ExitOnErr(errorOrToExpected(MemoryBuffer::getFileOrSTDIN(InputFilename))); 54 std::vector<BitcodeModule> Ms = ExitOnErr(getBitcodeModuleList(*MB)); 55 56 LLVMContext Context; 57 if (ModuleIndex >= Ms.size()) { 58 errs() << "llvm-modextract: error: module index out of range; bitcode file " 59 "contains " 60 << Ms.size() << " module(s)\n"; 61 return 1; 62 } 63 64 std::error_code EC; 65 std::unique_ptr<ToolOutputFile> Out( 66 new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None)); 67 ExitOnErr(errorCodeToError(EC)); 68 69 if (BinaryExtract) { 70 SmallVector<char, 0> Result; 71 BitcodeWriter Writer(Result); 72 Result.append(Ms[ModuleIndex].getBuffer().begin(), 73 Ms[ModuleIndex].getBuffer().end()); 74 Writer.copyStrtab(Ms[ModuleIndex].getStrtab()); 75 Out->os() << Result; 76 Out->keep(); 77 return 0; 78 } 79 80 std::unique_ptr<Module> M = ExitOnErr(Ms[ModuleIndex].parseModule(Context)); 81 WriteBitcodeToFile(*M, Out->os()); 82 83 Out->keep(); 84 return 0; 85 } 86