llvm-as.cpp revision 193323 
1//===--- llvm-as.cpp - The low-level LLVM assembler -----------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This utility may be invoked in the following manner:
11//   llvm-as --help         - Output information about command line switches
12//   llvm-as [options]      - Read LLVM asm from stdin, write bitcode to stdout
13//   llvm-as [options] x.ll - Read LLVM asm from the x.ll file, write bitcode
14//                            to the x.bc file.
15//
16//===----------------------------------------------------------------------===//
17
18#include "llvm/Module.h"
19#include "llvm/Assembly/Parser.h"
20#include "llvm/Analysis/Verifier.h"
21#include "llvm/Bitcode/ReaderWriter.h"
22#include "llvm/Support/CommandLine.h"
23#include "llvm/Support/ManagedStatic.h"
24#include "llvm/Support/PrettyStackTrace.h"
25#include "llvm/Support/Streams.h"
26#include "llvm/Support/SystemUtils.h"
27#include "llvm/Support/raw_ostream.h"
28#include "llvm/System/Signals.h"
29#include <fstream>
30#include <iostream>
31#include <memory>
32using namespace llvm;
33
34static cl::opt<std::string>
35InputFilename(cl::Positional, cl::desc("<input .llvm file>"), cl::init("-"));
36
37static cl::opt<std::string>
38OutputFilename("o", cl::desc("Override output filename"),
39               cl::value_desc("filename"));
40
41static cl::opt<bool>
42Force("f", cl::desc("Overwrite output files"));
43
44static cl::opt<bool>
45DisableOutput("disable-output", cl::desc("Disable output"), cl::init(false));
46
47static cl::opt<bool>
48DumpAsm("d", cl::desc("Print assembly as parsed"), cl::Hidden);
49
50static cl::opt<bool>
51DisableVerify("disable-verify", cl::Hidden,
52              cl::desc("Do not run verifier on input LLVM (dangerous!)"));
53
54int main(int argc, char **argv) {
55  // Print a stack trace if we signal out.
56  sys::PrintStackTraceOnErrorSignal();
57  PrettyStackTraceProgram X(argc, argv);
58  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
59  cl::ParseCommandLineOptions(argc, argv, "llvm .ll -> .bc assembler\n");
60
61  int exitCode = 0;
62  std::ostream *Out = 0;
63  try {
64    // Parse the file now...
65    ParseError Err;
66    std::auto_ptr<Module> M(ParseAssemblyFile(InputFilename, Err));
67    if (M.get() == 0) {
68      Err.PrintError(argv[0], errs());
69      return 1;
70    }
71
72    if (!DisableVerify) {
73      std::string Err;
74      if (verifyModule(*M.get(), ReturnStatusAction, &Err)) {
75        cerr << argv[0]
76             << ": assembly parsed, but does not verify as correct!\n";
77        cerr << Err;
78        return 1;
79      }
80    }
81
82    if (DumpAsm) cerr << "Here's the assembly:\n" << *M.get();
83
84    if (OutputFilename != "") {   // Specified an output filename?
85      if (OutputFilename != "-") {  // Not stdout?
86        if (!Force && std::ifstream(OutputFilename.c_str())) {
87          // If force is not specified, make sure not to overwrite a file!
88          cerr << argv[0] << ": error opening '" << OutputFilename
89               << "': file exists!\n"
90               << "Use -f command line argument to force output\n";
91          return 1;
92        }
93        Out = new std::ofstream(OutputFilename.c_str(), std::ios::out |
94                                std::ios::trunc | std::ios::binary);
95      } else {                      // Specified stdout
96        // FIXME: cout is not binary!
97        Out = &std::cout;
98      }
99    } else {
100      if (InputFilename == "-") {
101        OutputFilename = "-";
102        Out = &std::cout;
103      } else {
104        std::string IFN = InputFilename;
105        int Len = IFN.length();
106        if (IFN[Len-3] == '.' && IFN[Len-2] == 'l' && IFN[Len-1] == 'l') {
107          // Source ends in .ll
108          OutputFilename = std::string(IFN.begin(), IFN.end()-3);
109        } else {
110          OutputFilename = IFN;   // Append a .bc to it
111        }
112        OutputFilename += ".bc";
113
114        if (!Force && std::ifstream(OutputFilename.c_str())) {
115          // If force is not specified, make sure not to overwrite a file!
116          cerr << argv[0] << ": error opening '" << OutputFilename
117               << "': file exists!\n"
118               << "Use -f command line argument to force output\n";
119          return 1;
120        }
121
122        Out = new std::ofstream(OutputFilename.c_str(), std::ios::out |
123                                std::ios::trunc | std::ios::binary);
124        // Make sure that the Out file gets unlinked from the disk if we get a
125        // SIGINT
126        sys::RemoveFileOnSignal(sys::Path(OutputFilename));
127      }
128    }
129
130    if (!Out->good()) {
131      cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
132      return 1;
133    }
134
135    if (!DisableOutput)
136      if (Force || !CheckBitcodeOutputToConsole(Out,true))
137        WriteBitcodeToFile(M.get(), *Out);
138  } catch (const std::string& msg) {
139    cerr << argv[0] << ": " << msg << "\n";
140    exitCode = 1;
141  } catch (...) {
142    cerr << argv[0] << ": Unexpected unknown exception occurred.\n";
143    exitCode = 1;
144  }
145
146  if (Out != &std::cout) delete Out;
147  return exitCode;
148}
149
150