cc1as_main.cpp revision ea523d73a6de06f828952a02f5ff86e4cc631695 
1//===-- cc1as_main.cpp - Clang 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 is the entry point to the clang -cc1as functionality, which implements
11// the direct interface to the LLVM MC based assembler.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/Basic/Diagnostic.h"
16#include "clang/Driver/Arg.h"
17#include "clang/Driver/ArgList.h"
18#include "clang/Driver/DriverDiagnostic.h"
19#include "clang/Driver/CC1AsOptions.h"
20#include "clang/Driver/OptTable.h"
21#include "clang/Driver/Options.h"
22#include "clang/Frontend/DiagnosticOptions.h"
23#include "clang/Frontend/FrontendDiagnostic.h"
24#include "clang/Frontend/TextDiagnosticPrinter.h"
25#include "llvm/ADT/OwningPtr.h"
26#include "llvm/ADT/StringSwitch.h"
27#include "llvm/ADT/Triple.h"
28#include "llvm/MC/MCParser/MCAsmParser.h"
29#include "llvm/MC/MCAsmInfo.h"
30#include "llvm/MC/MCCodeEmitter.h"
31#include "llvm/MC/MCContext.h"
32#include "llvm/MC/MCInstrInfo.h"
33#include "llvm/MC/MCObjectFileInfo.h"
34#include "llvm/MC/MCRegisterInfo.h"
35#include "llvm/MC/MCStreamer.h"
36#include "llvm/MC/MCSubtargetInfo.h"
37#include "llvm/MC/MCAsmBackend.h"
38#include "llvm/MC/MCTargetAsmParser.h"
39#include "llvm/Support/CommandLine.h"
40#include "llvm/Support/FormattedStream.h"
41#include "llvm/Support/ErrorHandling.h"
42#include "llvm/Support/ManagedStatic.h"
43#include "llvm/Support/MemoryBuffer.h"
44#include "llvm/Support/PrettyStackTrace.h"
45#include "llvm/Support/SourceMgr.h"
46#include "llvm/Support/Host.h"
47#include "llvm/Support/Path.h"
48#include "llvm/Support/Signals.h"
49#include "llvm/Support/TargetRegistry.h"
50#include "llvm/Support/TargetSelect.h"
51#include "llvm/Support/Timer.h"
52#include "llvm/Support/raw_ostream.h"
53#include "llvm/Support/system_error.h"
54#include "llvm/Target/TargetData.h"
55using namespace clang;
56using namespace clang::driver;
57using namespace llvm;
58
59namespace {
60
61/// \brief Helper class for representing a single invocation of the assembler.
62struct AssemblerInvocation {
63  /// @name Target Options
64  /// @{
65
66  std::string Triple;
67
68  /// @}
69  /// @name Language Options
70  /// @{
71
72  std::vector<std::string> IncludePaths;
73  unsigned NoInitialTextSection : 1;
74  unsigned SaveTemporaryLabels : 1;
75
76  /// @}
77  /// @name Frontend Options
78  /// @{
79
80  std::string InputFile;
81  std::vector<std::string> LLVMArgs;
82  std::string OutputPath;
83  enum FileType {
84    FT_Asm,  ///< Assembly (.s) output, transliterate mode.
85    FT_Null, ///< No output, for timing purposes.
86    FT_Obj   ///< Object file output.
87  };
88  FileType OutputType;
89  unsigned ShowHelp : 1;
90  unsigned ShowVersion : 1;
91
92  /// @}
93  /// @name Transliterate Options
94  /// @{
95
96  unsigned OutputAsmVariant;
97  unsigned ShowEncoding : 1;
98  unsigned ShowInst : 1;
99
100  /// @}
101  /// @name Assembler Options
102  /// @{
103
104  unsigned RelaxAll : 1;
105  unsigned NoExecStack : 1;
106
107  /// @}
108
109public:
110  AssemblerInvocation() {
111    Triple = "";
112    NoInitialTextSection = 0;
113    InputFile = "-";
114    OutputPath = "-";
115    OutputType = FT_Asm;
116    OutputAsmVariant = 0;
117    ShowInst = 0;
118    ShowEncoding = 0;
119    RelaxAll = 0;
120    NoExecStack = 0;
121  }
122
123  static void CreateFromArgs(AssemblerInvocation &Res, const char **ArgBegin,
124                             const char **ArgEnd, DiagnosticsEngine &Diags);
125};
126
127}
128
129void AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
130                                         const char **ArgBegin,
131                                         const char **ArgEnd,
132                                         DiagnosticsEngine &Diags) {
133  using namespace clang::driver::cc1asoptions;
134  // Parse the arguments.
135  OwningPtr<OptTable> OptTbl(createCC1AsOptTable());
136  unsigned MissingArgIndex, MissingArgCount;
137  OwningPtr<InputArgList> Args(
138    OptTbl->ParseArgs(ArgBegin, ArgEnd,MissingArgIndex, MissingArgCount));
139
140  // Check for missing argument error.
141  if (MissingArgCount)
142    Diags.Report(diag::err_drv_missing_argument)
143      << Args->getArgString(MissingArgIndex) << MissingArgCount;
144
145  // Issue errors on unknown arguments.
146  for (arg_iterator it = Args->filtered_begin(cc1asoptions::OPT_UNKNOWN),
147         ie = Args->filtered_end(); it != ie; ++it)
148    Diags.Report(diag::err_drv_unknown_argument) << (*it) ->getAsString(*Args);
149
150  // Construct the invocation.
151
152  // Target Options
153  Opts.Triple = Triple::normalize(Args->getLastArgValue(OPT_triple));
154  if (Opts.Triple.empty()) // Use the host triple if unspecified.
155    Opts.Triple = sys::getHostTriple();
156
157  // Language Options
158  Opts.IncludePaths = Args->getAllArgValues(OPT_I);
159  Opts.NoInitialTextSection = Args->hasArg(OPT_n);
160  Opts.SaveTemporaryLabels = Args->hasArg(OPT_L);
161
162  // Frontend Options
163  if (Args->hasArg(OPT_INPUT)) {
164    bool First = true;
165    for (arg_iterator it = Args->filtered_begin(OPT_INPUT),
166           ie = Args->filtered_end(); it != ie; ++it, First=false) {
167      const Arg *A = it;
168      if (First)
169        Opts.InputFile = A->getValue(*Args);
170      else
171        Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(*Args);
172    }
173  }
174  Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
175  if (Args->hasArg(OPT_fatal_warnings))
176    Opts.LLVMArgs.push_back("-fatal-assembler-warnings");
177  Opts.OutputPath = Args->getLastArgValue(OPT_o);
178  if (Arg *A = Args->getLastArg(OPT_filetype)) {
179    StringRef Name = A->getValue(*Args);
180    unsigned OutputType = StringSwitch<unsigned>(Name)
181      .Case("asm", FT_Asm)
182      .Case("null", FT_Null)
183      .Case("obj", FT_Obj)
184      .Default(~0U);
185    if (OutputType == ~0U)
186      Diags.Report(diag::err_drv_invalid_value)
187        << A->getAsString(*Args) << Name;
188    else
189      Opts.OutputType = FileType(OutputType);
190  }
191  Opts.ShowHelp = Args->hasArg(OPT_help);
192  Opts.ShowVersion = Args->hasArg(OPT_version);
193
194  // Transliterate Options
195  Opts.OutputAsmVariant = Args->getLastArgIntValue(OPT_output_asm_variant,
196                                                   0, Diags);
197  Opts.ShowEncoding = Args->hasArg(OPT_show_encoding);
198  Opts.ShowInst = Args->hasArg(OPT_show_inst);
199
200  // Assemble Options
201  Opts.RelaxAll = Args->hasArg(OPT_relax_all);
202  Opts.NoExecStack =  Args->hasArg(OPT_no_exec_stack);
203}
204
205static formatted_raw_ostream *GetOutputStream(AssemblerInvocation &Opts,
206                                              DiagnosticsEngine &Diags,
207                                              bool Binary) {
208  if (Opts.OutputPath.empty())
209    Opts.OutputPath = "-";
210
211  // Make sure that the Out file gets unlinked from the disk if we get a
212  // SIGINT.
213  if (Opts.OutputPath != "-")
214    sys::RemoveFileOnSignal(sys::Path(Opts.OutputPath));
215
216  std::string Error;
217  raw_fd_ostream *Out =
218    new raw_fd_ostream(Opts.OutputPath.c_str(), Error,
219                       (Binary ? raw_fd_ostream::F_Binary : 0));
220  if (!Error.empty()) {
221    Diags.Report(diag::err_fe_unable_to_open_output)
222      << Opts.OutputPath << Error;
223    return 0;
224  }
225
226  return new formatted_raw_ostream(*Out, formatted_raw_ostream::DELETE_STREAM);
227}
228
229static bool ExecuteAssembler(AssemblerInvocation &Opts,
230                             DiagnosticsEngine &Diags) {
231  // Get the target specific parser.
232  std::string Error;
233  const Target *TheTarget(TargetRegistry::lookupTarget(Opts.Triple, Error));
234  if (!TheTarget) {
235    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
236    return false;
237  }
238
239  OwningPtr<MemoryBuffer> BufferPtr;
240  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Opts.InputFile, BufferPtr)) {
241    Error = ec.message();
242    Diags.Report(diag::err_fe_error_reading) << Opts.InputFile;
243    return false;
244  }
245  MemoryBuffer *Buffer = BufferPtr.take();
246
247  SourceMgr SrcMgr;
248
249  // Tell SrcMgr about this buffer, which is what the parser will pick up.
250  SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
251
252  // Record the location of the include directories so that the lexer can find
253  // it later.
254  SrcMgr.setIncludeDirs(Opts.IncludePaths);
255
256  OwningPtr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(Opts.Triple));
257  assert(MAI && "Unable to create target asm info!");
258
259  OwningPtr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
260  assert(MRI && "Unable to create target register info!");
261
262  bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
263  formatted_raw_ostream *Out = GetOutputStream(Opts, Diags, IsBinary);
264  if (!Out)
265    return false;
266
267  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
268  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
269  OwningPtr<MCObjectFileInfo> MOFI(new MCObjectFileInfo());
270  MCContext Ctx(*MAI, *MRI, MOFI.get());
271  // FIXME: Assembler behavior can change with -static.
272  MOFI->InitMCObjectFileInfo(Opts.Triple,
273                             Reloc::Default, CodeModel::Default, Ctx);
274  if (Opts.SaveTemporaryLabels)
275    Ctx.setAllowTemporaryLabels(false);
276
277  OwningPtr<MCStreamer> Str;
278
279  OwningPtr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
280  OwningPtr<MCSubtargetInfo>
281    STI(TheTarget->createMCSubtargetInfo(Opts.Triple, "", ""));
282
283  // FIXME: There is a bit of code duplication with addPassesToEmitFile.
284  if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
285    MCInstPrinter *IP =
286      TheTarget->createMCInstPrinter(Opts.OutputAsmVariant, *MAI, *STI);
287    MCCodeEmitter *CE = 0;
288    MCAsmBackend *MAB = 0;
289    if (Opts.ShowEncoding) {
290      CE = TheTarget->createMCCodeEmitter(*MCII, *STI, Ctx);
291      MAB = TheTarget->createMCAsmBackend(Opts.Triple);
292    }
293    Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
294                                           /*useLoc*/ true,
295                                           /*useCFI*/ true,
296                                           /*useDwarfDirectory*/ true,
297                                           IP, CE, MAB,
298                                           Opts.ShowInst));
299  } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
300    Str.reset(createNullStreamer(Ctx));
301  } else {
302    assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
303           "Invalid file type!");
304    MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *STI, Ctx);
305    MCAsmBackend *MAB = TheTarget->createMCAsmBackend(Opts.Triple);
306    Str.reset(TheTarget->createMCObjectStreamer(Opts.Triple, Ctx, *MAB, *Out,
307                                                CE, Opts.RelaxAll,
308                                                Opts.NoExecStack));
309    Str.get()->InitSections();
310  }
311
312  OwningPtr<MCAsmParser> Parser(createMCAsmParser(SrcMgr, Ctx,
313                                                  *Str.get(), *MAI));
314  OwningPtr<MCTargetAsmParser> TAP(TheTarget->createMCAsmParser(*STI, *Parser));
315  if (!TAP) {
316    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
317    return false;
318  }
319
320  Parser->setTargetParser(*TAP.get());
321
322  bool Success = !Parser->Run(Opts.NoInitialTextSection);
323
324  // Close the output.
325  delete Out;
326
327  // Delete output on errors.
328  if (!Success && Opts.OutputPath != "-")
329    sys::Path(Opts.OutputPath).eraseFromDisk();
330
331  return Success;
332}
333
334static void LLVMErrorHandler(void *UserData, const std::string &Message) {
335  DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
336
337  Diags.Report(diag::err_fe_error_backend) << Message;
338
339  // We cannot recover from llvm errors.
340  exit(1);
341}
342
343int cc1as_main(const char **ArgBegin, const char **ArgEnd,
344               const char *Argv0, void *MainAddr) {
345  // Print a stack trace if we signal out.
346  sys::PrintStackTraceOnErrorSignal();
347  PrettyStackTraceProgram X(ArgEnd - ArgBegin, ArgBegin);
348  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
349
350  // Initialize targets and assembly printers/parsers.
351  InitializeAllTargetInfos();
352  InitializeAllTargetMCs();
353  InitializeAllAsmParsers();
354
355  // Construct our diagnostic client.
356  TextDiagnosticPrinter *DiagClient
357    = new TextDiagnosticPrinter(errs(), DiagnosticOptions());
358  DiagClient->setPrefix("clang -cc1as");
359  llvm::IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
360  DiagnosticsEngine Diags(DiagID, DiagClient);
361
362  // Set an error handler, so that any LLVM backend diagnostics go through our
363  // error handler.
364  ScopedFatalErrorHandler FatalErrorHandler
365    (LLVMErrorHandler, static_cast<void*>(&Diags));
366
367  // Parse the arguments.
368  AssemblerInvocation Asm;
369  AssemblerInvocation::CreateFromArgs(Asm, ArgBegin, ArgEnd, Diags);
370
371  // Honor -help.
372  if (Asm.ShowHelp) {
373    llvm::OwningPtr<driver::OptTable> Opts(driver::createCC1AsOptTable());
374    Opts->PrintHelp(llvm::outs(), "clang -cc1as", "Clang Integrated Assembler");
375    return 0;
376  }
377
378  // Honor -version.
379  //
380  // FIXME: Use a better -version message?
381  if (Asm.ShowVersion) {
382    llvm::cl::PrintVersionMessage();
383    return 0;
384  }
385
386  // Honor -mllvm.
387  //
388  // FIXME: Remove this, one day.
389  if (!Asm.LLVMArgs.empty()) {
390    unsigned NumArgs = Asm.LLVMArgs.size();
391    const char **Args = new const char*[NumArgs + 2];
392    Args[0] = "clang (LLVM option parsing)";
393    for (unsigned i = 0; i != NumArgs; ++i)
394      Args[i + 1] = Asm.LLVMArgs[i].c_str();
395    Args[NumArgs + 1] = 0;
396    llvm::cl::ParseCommandLineOptions(NumArgs + 1, const_cast<char **>(Args));
397  }
398
399  // Execute the invocation, unless there were parsing errors.
400  bool Success = false;
401  if (!Diags.hasErrorOccurred())
402    Success = ExecuteAssembler(Asm, Diags);
403
404  // If any timers were active but haven't been destroyed yet, print their
405  // results now.
406  TimerGroup::printAll(errs());
407
408  return !Success;
409}
410