1 //===-- llvm-dis.cpp - The low-level LLVM disassembler --------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This utility may be invoked in the following manner:
11 // llvm-dis [options] - Read LLVM bytecode from stdin, write asm to stdout
12 // llvm-dis [options] x.bc - Read LLVM bytecode from the x.bc file, write asm
15 // --help - Output information about command line switches
17 //===----------------------------------------------------------------------===//
19 #include "llvm/Module.h"
20 #include "llvm/PassManager.h"
21 #include "llvm/Bitcode/ReaderWriter.h"
22 #include "llvm/Assembly/PrintModulePass.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/ManagedStatic.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/Streams.h"
27 #include "llvm/System/Signals.h"
33 static cl::opt<std::string>
34 InputFilename(cl::Positional, cl::desc("<input bytecode>"), cl::init("-"));
36 static cl::opt<std::string>
37 OutputFilename("o", cl::desc("Override output filename"),
38 cl::value_desc("filename"));
41 Force("f", cl::desc("Overwrite output files"));
44 DontPrint("disable-output", cl::desc("Don't output the .ll file"), cl::Hidden);
46 int main(int argc, char **argv) {
47 llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
49 cl::ParseCommandLineOptions(argc, argv, " llvm .bc -> .ll disassembler\n");
50 sys::PrintStackTraceOnErrorSignal();
52 std::ostream *Out = &std::cout; // Default to printing to stdout.
53 std::string ErrorMessage;
55 std::auto_ptr<Module> M;
58 = MemoryBuffer::getFileOrSTDIN(&InputFilename[0], InputFilename.size());
61 ErrorMessage = "Error reading file '" + InputFilename + "'";
63 M.reset(ParseBitcodeFile(Buffer, &ErrorMessage));
67 cerr << argv[0] << ": ";
68 if (ErrorMessage.size())
69 cerr << ErrorMessage << "\n";
71 cerr << "bytecode didn't read correctly.\n";
76 // Just use stdout. We won't actually print anything on it.
77 } else if (OutputFilename != "") { // Specified an output filename?
78 if (OutputFilename != "-") { // Not stdout?
79 if (!Force && std::ifstream(OutputFilename.c_str())) {
80 // If force is not specified, make sure not to overwrite a file!
81 cerr << argv[0] << ": error opening '" << OutputFilename
82 << "': file exists! Sending to standard output.\n";
84 Out = new std::ofstream(OutputFilename.c_str());
88 if (InputFilename == "-") {
91 std::string IFN = InputFilename;
92 int Len = IFN.length();
93 if (IFN[Len-3] == '.' && IFN[Len-2] == 'b' && IFN[Len-1] == 'c') {
95 OutputFilename = std::string(IFN.begin(), IFN.end()-3)+".ll";
97 OutputFilename = IFN+".ll";
100 if (!Force && std::ifstream(OutputFilename.c_str())) {
101 // If force is not specified, make sure not to overwrite a file!
102 cerr << argv[0] << ": error opening '" << OutputFilename
103 << "': file exists! Sending to standard output.\n";
105 Out = new std::ofstream(OutputFilename.c_str());
107 // Make sure that the Out file gets unlinked from the disk if we get a
109 sys::RemoveFileOnSignal(sys::Path(OutputFilename));
115 cerr << argv[0] << ": error opening " << OutputFilename
116 << ": sending to stdout instead!\n";
120 // All that llvm-dis does is write the assembly to a file.
124 Passes.add(new PrintModulePass(&L));
125 Passes.run(*M.get());
128 if (Out != &std::cout) {
129 ((std::ofstream*)Out)->close();
133 } catch (const std::string& msg) {
134 cerr << argv[0] << ": " << msg << "\n";
136 cerr << argv[0] << ": Unexpected unknown exception occurred.\n";