cc1as_main.cpp revision c93dc7889644293e318e19d82830ea2acc45b678 
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  /// The name of the target triple to assemble for.
67  std::string Triple;
68
69  /// If given, the name of the target CPU to determine which instructions
70  /// are legal.
71  std::string CPU;
72
73  /// The list of target specific features to enable or disable -- this should
74  /// be a list of strings starting with '+' or '-'.
75  std::vector<std::string> Features;
76
77  /// @}
78  /// @name Language Options
79  /// @{
80
81  std::vector<std::string> IncludePaths;
82  unsigned NoInitialTextSection : 1;
83  unsigned SaveTemporaryLabels : 1;
84  unsigned GenDwarfForAssembly : 1;
85  std::string DwarfDebugFlags;
86
87  /// @}
88  /// @name Frontend Options
89  /// @{
90
91  std::string InputFile;
92  std::vector<std::string> LLVMArgs;
93  std::string OutputPath;
94  enum FileType {
95    FT_Asm,  ///< Assembly (.s) output, transliterate mode.
96    FT_Null, ///< No output, for timing purposes.
97    FT_Obj   ///< Object file output.
98  };
99  FileType OutputType;
100  unsigned ShowHelp : 1;
101  unsigned ShowVersion : 1;
102
103  /// @}
104  /// @name Transliterate Options
105  /// @{
106
107  unsigned OutputAsmVariant;
108  unsigned ShowEncoding : 1;
109  unsigned ShowInst : 1;
110
111  /// @}
112  /// @name Assembler Options
113  /// @{
114
115  unsigned RelaxAll : 1;
116  unsigned NoExecStack : 1;
117
118  /// @}
119
120public:
121  AssemblerInvocation() {
122    Triple = "";
123    NoInitialTextSection = 0;
124    InputFile = "-";
125    OutputPath = "-";
126    OutputType = FT_Asm;
127    OutputAsmVariant = 0;
128    ShowInst = 0;
129    ShowEncoding = 0;
130    RelaxAll = 0;
131    NoExecStack = 0;
132  }
133
134  static bool CreateFromArgs(AssemblerInvocation &Res, const char **ArgBegin,
135                             const char **ArgEnd, DiagnosticsEngine &Diags);
136};
137
138}
139
140bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
141                                         const char **ArgBegin,
142                                         const char **ArgEnd,
143                                         DiagnosticsEngine &Diags) {
144  using namespace clang::driver::cc1asoptions;
145  bool Success = true;
146
147  // Parse the arguments.
148  OwningPtr<OptTable> OptTbl(createCC1AsOptTable());
149  unsigned MissingArgIndex, MissingArgCount;
150  OwningPtr<InputArgList> Args(
151    OptTbl->ParseArgs(ArgBegin, ArgEnd,MissingArgIndex, MissingArgCount));
152
153  // Check for missing argument error.
154  if (MissingArgCount) {
155    Diags.Report(diag::err_drv_missing_argument)
156      << Args->getArgString(MissingArgIndex) << MissingArgCount;
157    Success = false;
158  }
159
160  // Issue errors on unknown arguments.
161  for (arg_iterator it = Args->filtered_begin(cc1asoptions::OPT_UNKNOWN),
162         ie = Args->filtered_end(); it != ie; ++it) {
163    Diags.Report(diag::err_drv_unknown_argument) << (*it) ->getAsString(*Args);
164    Success = false;
165  }
166
167  // Construct the invocation.
168
169  // Target Options
170  Opts.Triple = llvm::Triple::normalize(Args->getLastArgValue(OPT_triple));
171  Opts.CPU = Args->getLastArgValue(OPT_target_cpu);
172  Opts.Features = Args->getAllArgValues(OPT_target_feature);
173
174  // Use the default target triple if unspecified.
175  if (Opts.Triple.empty())
176    Opts.Triple = llvm::sys::getDefaultTargetTriple();
177
178  // Language Options
179  Opts.IncludePaths = Args->getAllArgValues(OPT_I);
180  Opts.NoInitialTextSection = Args->hasArg(OPT_n);
181  Opts.SaveTemporaryLabels = Args->hasArg(OPT_L);
182  Opts.GenDwarfForAssembly = Args->hasArg(OPT_g);
183  Opts.DwarfDebugFlags = Args->getLastArgValue(OPT_dwarf_debug_flags);
184
185  // Frontend Options
186  if (Args->hasArg(OPT_INPUT)) {
187    bool First = true;
188    for (arg_iterator it = Args->filtered_begin(OPT_INPUT),
189           ie = Args->filtered_end(); it != ie; ++it, First=false) {
190      const Arg *A = it;
191      if (First)
192        Opts.InputFile = A->getValue(*Args);
193      else {
194        Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(*Args);
195        Success = false;
196      }
197    }
198  }
199  Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
200  if (Args->hasArg(OPT_fatal_warnings))
201    Opts.LLVMArgs.push_back("-fatal-assembler-warnings");
202  Opts.OutputPath = Args->getLastArgValue(OPT_o);
203  if (Arg *A = Args->getLastArg(OPT_filetype)) {
204    StringRef Name = A->getValue(*Args);
205    unsigned OutputType = StringSwitch<unsigned>(Name)
206      .Case("asm", FT_Asm)
207      .Case("null", FT_Null)
208      .Case("obj", FT_Obj)
209      .Default(~0U);
210    if (OutputType == ~0U) {
211      Diags.Report(diag::err_drv_invalid_value)
212        << A->getAsString(*Args) << Name;
213      Success = false;
214    } else
215      Opts.OutputType = FileType(OutputType);
216  }
217  Opts.ShowHelp = Args->hasArg(OPT_help);
218  Opts.ShowVersion = Args->hasArg(OPT_version);
219
220  // Transliterate Options
221  Opts.OutputAsmVariant = Args->getLastArgIntValue(OPT_output_asm_variant,
222                                                   0, Diags);
223  Opts.ShowEncoding = Args->hasArg(OPT_show_encoding);
224  Opts.ShowInst = Args->hasArg(OPT_show_inst);
225
226  // Assemble Options
227  Opts.RelaxAll = Args->hasArg(OPT_relax_all);
228  Opts.NoExecStack =  Args->hasArg(OPT_no_exec_stack);
229
230  return Success;
231}
232
233static formatted_raw_ostream *GetOutputStream(AssemblerInvocation &Opts,
234                                              DiagnosticsEngine &Diags,
235                                              bool Binary) {
236  if (Opts.OutputPath.empty())
237    Opts.OutputPath = "-";
238
239  // Make sure that the Out file gets unlinked from the disk if we get a
240  // SIGINT.
241  if (Opts.OutputPath != "-")
242    sys::RemoveFileOnSignal(sys::Path(Opts.OutputPath));
243
244  std::string Error;
245  raw_fd_ostream *Out =
246    new raw_fd_ostream(Opts.OutputPath.c_str(), Error,
247                       (Binary ? raw_fd_ostream::F_Binary : 0));
248  if (!Error.empty()) {
249    Diags.Report(diag::err_fe_unable_to_open_output)
250      << Opts.OutputPath << Error;
251    return 0;
252  }
253
254  return new formatted_raw_ostream(*Out, formatted_raw_ostream::DELETE_STREAM);
255}
256
257static bool ExecuteAssembler(AssemblerInvocation &Opts,
258                             DiagnosticsEngine &Diags) {
259  // Get the target specific parser.
260  std::string Error;
261  const Target *TheTarget(TargetRegistry::lookupTarget(Opts.Triple, Error));
262  if (!TheTarget) {
263    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
264    return false;
265  }
266
267  OwningPtr<MemoryBuffer> BufferPtr;
268  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Opts.InputFile, BufferPtr)) {
269    Error = ec.message();
270    Diags.Report(diag::err_fe_error_reading) << Opts.InputFile;
271    return false;
272  }
273  MemoryBuffer *Buffer = BufferPtr.take();
274
275  SourceMgr SrcMgr;
276
277  // Tell SrcMgr about this buffer, which is what the parser will pick up.
278  SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
279
280  // Record the location of the include directories so that the lexer can find
281  // it later.
282  SrcMgr.setIncludeDirs(Opts.IncludePaths);
283
284  OwningPtr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(Opts.Triple));
285  assert(MAI && "Unable to create target asm info!");
286
287  OwningPtr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
288  assert(MRI && "Unable to create target register info!");
289
290  bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
291  formatted_raw_ostream *Out = GetOutputStream(Opts, Diags, IsBinary);
292  if (!Out)
293    return false;
294
295  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
296  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
297  OwningPtr<MCObjectFileInfo> MOFI(new MCObjectFileInfo());
298  MCContext Ctx(*MAI, *MRI, MOFI.get(), &SrcMgr);
299  // FIXME: Assembler behavior can change with -static.
300  MOFI->InitMCObjectFileInfo(Opts.Triple,
301                             Reloc::Default, CodeModel::Default, Ctx);
302  if (Opts.SaveTemporaryLabels)
303    Ctx.setAllowTemporaryLabels(false);
304  if (Opts.GenDwarfForAssembly)
305    Ctx.setGenDwarfForAssembly(true);
306  if (!Opts.DwarfDebugFlags.empty())
307    Ctx.setDwarfDebugFlags(StringRef(Opts.DwarfDebugFlags));
308
309  // Build up the feature string from the target feature list.
310  std::string FS;
311  if (!Opts.Features.empty()) {
312    FS = Opts.Features[0];
313    for (unsigned i = 1, e = Opts.Features.size(); i != e; ++i)
314      FS += "," + Opts.Features[i];
315  }
316
317  OwningPtr<MCStreamer> Str;
318
319  OwningPtr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
320  OwningPtr<MCSubtargetInfo>
321    STI(TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
322
323  // FIXME: There is a bit of code duplication with addPassesToEmitFile.
324  if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
325    MCInstPrinter *IP =
326      TheTarget->createMCInstPrinter(Opts.OutputAsmVariant, *MAI, *STI);
327    MCCodeEmitter *CE = 0;
328    MCAsmBackend *MAB = 0;
329    if (Opts.ShowEncoding) {
330      CE = TheTarget->createMCCodeEmitter(*MCII, *STI, Ctx);
331      MAB = TheTarget->createMCAsmBackend(Opts.Triple);
332    }
333    Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
334                                           /*useLoc*/ true,
335                                           /*useCFI*/ true,
336                                           /*useDwarfDirectory*/ true,
337                                           IP, CE, MAB,
338                                           Opts.ShowInst));
339  } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
340    Str.reset(createNullStreamer(Ctx));
341  } else {
342    assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
343           "Invalid file type!");
344    MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *STI, Ctx);
345    MCAsmBackend *MAB = TheTarget->createMCAsmBackend(Opts.Triple);
346    Str.reset(TheTarget->createMCObjectStreamer(Opts.Triple, Ctx, *MAB, *Out,
347                                                CE, Opts.RelaxAll,
348                                                Opts.NoExecStack));
349    Str.get()->InitSections();
350  }
351
352  OwningPtr<MCAsmParser> Parser(createMCAsmParser(SrcMgr, Ctx,
353                                                  *Str.get(), *MAI));
354  OwningPtr<MCTargetAsmParser> TAP(TheTarget->createMCAsmParser(*STI, *Parser));
355  if (!TAP) {
356    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
357    return false;
358  }
359
360  Parser->setTargetParser(*TAP.get());
361
362  bool Success = !Parser->Run(Opts.NoInitialTextSection);
363
364  // Close the output.
365  delete Out;
366
367  // Delete output on errors.
368  if (!Success && Opts.OutputPath != "-")
369    sys::Path(Opts.OutputPath).eraseFromDisk();
370
371  return Success;
372}
373
374static void LLVMErrorHandler(void *UserData, const std::string &Message) {
375  DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
376
377  Diags.Report(diag::err_fe_error_backend) << Message;
378
379  // We cannot recover from llvm errors.
380  exit(1);
381}
382
383int cc1as_main(const char **ArgBegin, const char **ArgEnd,
384               const char *Argv0, void *MainAddr) {
385  // Print a stack trace if we signal out.
386  sys::PrintStackTraceOnErrorSignal();
387  PrettyStackTraceProgram X(ArgEnd - ArgBegin, ArgBegin);
388  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
389
390  // Initialize targets and assembly printers/parsers.
391  InitializeAllTargetInfos();
392  InitializeAllTargetMCs();
393  InitializeAllAsmParsers();
394
395  // Construct our diagnostic client.
396  TextDiagnosticPrinter *DiagClient
397    = new TextDiagnosticPrinter(errs(), DiagnosticOptions());
398  DiagClient->setPrefix("clang -cc1as");
399  IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
400  DiagnosticsEngine Diags(DiagID, DiagClient);
401
402  // Set an error handler, so that any LLVM backend diagnostics go through our
403  // error handler.
404  ScopedFatalErrorHandler FatalErrorHandler
405    (LLVMErrorHandler, static_cast<void*>(&Diags));
406
407  // Parse the arguments.
408  AssemblerInvocation Asm;
409  if (!AssemblerInvocation::CreateFromArgs(Asm, ArgBegin, ArgEnd, Diags))
410    return 1;
411
412  // Honor -help.
413  if (Asm.ShowHelp) {
414    OwningPtr<driver::OptTable> Opts(driver::createCC1AsOptTable());
415    Opts->PrintHelp(llvm::outs(), "clang -cc1as", "Clang Integrated Assembler");
416    return 0;
417  }
418
419  // Honor -version.
420  //
421  // FIXME: Use a better -version message?
422  if (Asm.ShowVersion) {
423    llvm::cl::PrintVersionMessage();
424    return 0;
425  }
426
427  // Honor -mllvm.
428  //
429  // FIXME: Remove this, one day.
430  if (!Asm.LLVMArgs.empty()) {
431    unsigned NumArgs = Asm.LLVMArgs.size();
432    const char **Args = new const char*[NumArgs + 2];
433    Args[0] = "clang (LLVM option parsing)";
434    for (unsigned i = 0; i != NumArgs; ++i)
435      Args[i + 1] = Asm.LLVMArgs[i].c_str();
436    Args[NumArgs + 1] = 0;
437    llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args);
438  }
439
440  // Execute the invocation, unless there were parsing errors.
441  bool Success = false;
442  if (!Diags.hasErrorOccurred())
443    Success = ExecuteAssembler(Asm, Diags);
444
445  // If any timers were active but haven't been destroyed yet, print their
446  // results now.
447  TimerGroup::printAll(errs());
448
449  return !Success;
450}
451