cc1as_main.cpp revision 9083628fec737679eb95abe8e2e5e23717a96e18 
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/Basic/DiagnosticOptions.h"
17#include "clang/Driver/Arg.h"
18#include "clang/Driver/ArgList.h"
19#include "clang/Driver/CC1AsOptions.h"
20#include "clang/Driver/DriverDiagnostic.h"
21#include "clang/Driver/OptTable.h"
22#include "clang/Driver/Options.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/IR/DataLayout.h"
29#include "llvm/MC/MCAsmBackend.h"
30#include "llvm/MC/MCAsmInfo.h"
31#include "llvm/MC/MCCodeEmitter.h"
32#include "llvm/MC/MCContext.h"
33#include "llvm/MC/MCInstrInfo.h"
34#include "llvm/MC/MCObjectFileInfo.h"
35#include "llvm/MC/MCParser/MCAsmParser.h"
36#include "llvm/MC/MCRegisterInfo.h"
37#include "llvm/MC/MCStreamer.h"
38#include "llvm/MC/MCSubtargetInfo.h"
39#include "llvm/MC/MCTargetAsmParser.h"
40#include "llvm/Support/CommandLine.h"
41#include "llvm/Support/ErrorHandling.h"
42#include "llvm/Support/FormattedStream.h"
43#include "llvm/Support/Host.h"
44#include "llvm/Support/ManagedStatic.h"
45#include "llvm/Support/MemoryBuffer.h"
46#include "llvm/Support/Path.h"
47#include "llvm/Support/PrettyStackTrace.h"
48#include "llvm/Support/Signals.h"
49#include "llvm/Support/SourceMgr.h"
50#include "llvm/Support/TargetRegistry.h"
51#include "llvm/Support/TargetSelect.h"
52#include "llvm/Support/Timer.h"
53#include "llvm/Support/raw_ostream.h"
54#include "llvm/Support/system_error.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  std::string DwarfDebugProducer;
87  std::string DebugCompilationDir;
88  std::string MainFileName;
89
90  /// @}
91  /// @name Frontend Options
92  /// @{
93
94  std::string InputFile;
95  std::vector<std::string> LLVMArgs;
96  std::string OutputPath;
97  enum FileType {
98    FT_Asm,  ///< Assembly (.s) output, transliterate mode.
99    FT_Null, ///< No output, for timing purposes.
100    FT_Obj   ///< Object file output.
101  };
102  FileType OutputType;
103  unsigned ShowHelp : 1;
104  unsigned ShowVersion : 1;
105
106  /// @}
107  /// @name Transliterate Options
108  /// @{
109
110  unsigned OutputAsmVariant;
111  unsigned ShowEncoding : 1;
112  unsigned ShowInst : 1;
113
114  /// @}
115  /// @name Assembler Options
116  /// @{
117
118  unsigned RelaxAll : 1;
119  unsigned NoExecStack : 1;
120
121  /// @}
122
123public:
124  AssemblerInvocation() {
125    Triple = "";
126    NoInitialTextSection = 0;
127    InputFile = "-";
128    OutputPath = "-";
129    OutputType = FT_Asm;
130    OutputAsmVariant = 0;
131    ShowInst = 0;
132    ShowEncoding = 0;
133    RelaxAll = 0;
134    NoExecStack = 0;
135  }
136
137  static bool CreateFromArgs(AssemblerInvocation &Res, const char **ArgBegin,
138                             const char **ArgEnd, DiagnosticsEngine &Diags);
139};
140
141}
142
143bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
144                                         const char **ArgBegin,
145                                         const char **ArgEnd,
146                                         DiagnosticsEngine &Diags) {
147  using namespace clang::driver::cc1asoptions;
148  bool Success = true;
149
150  // Parse the arguments.
151  OwningPtr<OptTable> OptTbl(createCC1AsOptTable());
152  unsigned MissingArgIndex, MissingArgCount;
153  OwningPtr<InputArgList> Args(
154    OptTbl->ParseArgs(ArgBegin, ArgEnd,MissingArgIndex, MissingArgCount));
155
156  // Check for missing argument error.
157  if (MissingArgCount) {
158    Diags.Report(diag::err_drv_missing_argument)
159      << Args->getArgString(MissingArgIndex) << MissingArgCount;
160    Success = false;
161  }
162
163  // Issue errors on unknown arguments.
164  for (arg_iterator it = Args->filtered_begin(cc1asoptions::OPT_UNKNOWN),
165         ie = Args->filtered_end(); it != ie; ++it) {
166    Diags.Report(diag::err_drv_unknown_argument) << (*it) ->getAsString(*Args);
167    Success = false;
168  }
169
170  // Construct the invocation.
171
172  // Target Options
173  Opts.Triple = llvm::Triple::normalize(Args->getLastArgValue(OPT_triple));
174  Opts.CPU = Args->getLastArgValue(OPT_target_cpu);
175  Opts.Features = Args->getAllArgValues(OPT_target_feature);
176
177  // Use the default target triple if unspecified.
178  if (Opts.Triple.empty())
179    Opts.Triple = llvm::sys::getDefaultTargetTriple();
180
181  // Language Options
182  Opts.IncludePaths = Args->getAllArgValues(OPT_I);
183  Opts.NoInitialTextSection = Args->hasArg(OPT_n);
184  Opts.SaveTemporaryLabels = Args->hasArg(OPT_L);
185  Opts.GenDwarfForAssembly = Args->hasArg(OPT_g);
186  Opts.DwarfDebugFlags = Args->getLastArgValue(OPT_dwarf_debug_flags);
187  Opts.DwarfDebugProducer = Args->getLastArgValue(OPT_dwarf_debug_producer);
188  Opts.DebugCompilationDir = Args->getLastArgValue(OPT_fdebug_compilation_dir);
189  Opts.MainFileName = Args->getLastArgValue(OPT_main_file_name);
190
191  // Frontend Options
192  if (Args->hasArg(OPT_INPUT)) {
193    bool First = true;
194    for (arg_iterator it = Args->filtered_begin(OPT_INPUT),
195           ie = Args->filtered_end(); it != ie; ++it, First=false) {
196      const Arg *A = it;
197      if (First)
198        Opts.InputFile = A->getValue();
199      else {
200        Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(*Args);
201        Success = false;
202      }
203    }
204  }
205  Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
206  if (Args->hasArg(OPT_fatal_warnings))
207    Opts.LLVMArgs.push_back("-fatal-assembler-warnings");
208  Opts.OutputPath = Args->getLastArgValue(OPT_o);
209  if (Arg *A = Args->getLastArg(OPT_filetype)) {
210    StringRef Name = A->getValue();
211    unsigned OutputType = StringSwitch<unsigned>(Name)
212      .Case("asm", FT_Asm)
213      .Case("null", FT_Null)
214      .Case("obj", FT_Obj)
215      .Default(~0U);
216    if (OutputType == ~0U) {
217      Diags.Report(diag::err_drv_invalid_value)
218        << A->getAsString(*Args) << Name;
219      Success = false;
220    } else
221      Opts.OutputType = FileType(OutputType);
222  }
223  Opts.ShowHelp = Args->hasArg(OPT_help);
224  Opts.ShowVersion = Args->hasArg(OPT_version);
225
226  // Transliterate Options
227  Opts.OutputAsmVariant = Args->getLastArgIntValue(OPT_output_asm_variant,
228                                                   0, Diags);
229  Opts.ShowEncoding = Args->hasArg(OPT_show_encoding);
230  Opts.ShowInst = Args->hasArg(OPT_show_inst);
231
232  // Assemble Options
233  Opts.RelaxAll = Args->hasArg(OPT_relax_all);
234  Opts.NoExecStack =  Args->hasArg(OPT_no_exec_stack);
235
236  return Success;
237}
238
239static formatted_raw_ostream *GetOutputStream(AssemblerInvocation &Opts,
240                                              DiagnosticsEngine &Diags,
241                                              bool Binary) {
242  if (Opts.OutputPath.empty())
243    Opts.OutputPath = "-";
244
245  // Make sure that the Out file gets unlinked from the disk if we get a
246  // SIGINT.
247  if (Opts.OutputPath != "-")
248    sys::RemoveFileOnSignal(sys::Path(Opts.OutputPath));
249
250  std::string Error;
251  raw_fd_ostream *Out =
252    new raw_fd_ostream(Opts.OutputPath.c_str(), Error,
253                       (Binary ? raw_fd_ostream::F_Binary : 0));
254  if (!Error.empty()) {
255    Diags.Report(diag::err_fe_unable_to_open_output)
256      << Opts.OutputPath << Error;
257    return 0;
258  }
259
260  return new formatted_raw_ostream(*Out, formatted_raw_ostream::DELETE_STREAM);
261}
262
263static bool ExecuteAssembler(AssemblerInvocation &Opts,
264                             DiagnosticsEngine &Diags) {
265  // Get the target specific parser.
266  std::string Error;
267  const Target *TheTarget(TargetRegistry::lookupTarget(Opts.Triple, Error));
268  if (!TheTarget) {
269    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
270    return false;
271  }
272
273  OwningPtr<MemoryBuffer> BufferPtr;
274  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Opts.InputFile, BufferPtr)) {
275    Error = ec.message();
276    Diags.Report(diag::err_fe_error_reading) << Opts.InputFile;
277    return false;
278  }
279  MemoryBuffer *Buffer = BufferPtr.take();
280
281  SourceMgr SrcMgr;
282
283  // Tell SrcMgr about this buffer, which is what the parser will pick up.
284  SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
285
286  // Record the location of the include directories so that the lexer can find
287  // it later.
288  SrcMgr.setIncludeDirs(Opts.IncludePaths);
289
290  OwningPtr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(Opts.Triple));
291  assert(MAI && "Unable to create target asm info!");
292
293  OwningPtr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
294  assert(MRI && "Unable to create target register info!");
295
296  bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
297  formatted_raw_ostream *Out = GetOutputStream(Opts, Diags, IsBinary);
298  if (!Out)
299    return false;
300
301  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
302  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
303  OwningPtr<MCObjectFileInfo> MOFI(new MCObjectFileInfo());
304  MCContext Ctx(*MAI, *MRI, MOFI.get(), &SrcMgr);
305  // FIXME: Assembler behavior can change with -static.
306  MOFI->InitMCObjectFileInfo(Opts.Triple,
307                             Reloc::Default, CodeModel::Default, Ctx);
308  if (Opts.SaveTemporaryLabels)
309    Ctx.setAllowTemporaryLabels(false);
310  if (Opts.GenDwarfForAssembly)
311    Ctx.setGenDwarfForAssembly(true);
312  if (!Opts.DwarfDebugFlags.empty())
313    Ctx.setDwarfDebugFlags(StringRef(Opts.DwarfDebugFlags));
314  if (!Opts.DwarfDebugProducer.empty())
315    Ctx.setDwarfDebugProducer(StringRef(Opts.DwarfDebugProducer));
316  if (!Opts.DebugCompilationDir.empty())
317    Ctx.setCompilationDir(Opts.DebugCompilationDir);
318  if (!Opts.MainFileName.empty())
319    Ctx.setMainFileName(StringRef(Opts.MainFileName));
320
321  // Build up the feature string from the target feature list.
322  std::string FS;
323  if (!Opts.Features.empty()) {
324    FS = Opts.Features[0];
325    for (unsigned i = 1, e = Opts.Features.size(); i != e; ++i)
326      FS += "," + Opts.Features[i];
327  }
328
329  OwningPtr<MCStreamer> Str;
330
331  OwningPtr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
332  OwningPtr<MCSubtargetInfo>
333    STI(TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
334
335  // FIXME: There is a bit of code duplication with addPassesToEmitFile.
336  if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
337    MCInstPrinter *IP =
338      TheTarget->createMCInstPrinter(Opts.OutputAsmVariant, *MAI, *MCII, *MRI,
339                                     *STI);
340    MCCodeEmitter *CE = 0;
341    MCAsmBackend *MAB = 0;
342    if (Opts.ShowEncoding) {
343      CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
344      MAB = TheTarget->createMCAsmBackend(Opts.Triple, Opts.CPU);
345    }
346    Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
347                                           /*useLoc*/ true,
348                                           /*useCFI*/ true,
349                                           /*useDwarfDirectory*/ true,
350                                           IP, CE, MAB,
351                                           Opts.ShowInst));
352  } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
353    Str.reset(createNullStreamer(Ctx));
354  } else {
355    assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
356           "Invalid file type!");
357    MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
358    MCAsmBackend *MAB = TheTarget->createMCAsmBackend(Opts.Triple, Opts.CPU);
359    Str.reset(TheTarget->createMCObjectStreamer(Opts.Triple, Ctx, *MAB, *Out,
360                                                CE, Opts.RelaxAll,
361                                                Opts.NoExecStack));
362    Str.get()->InitSections();
363  }
364
365  OwningPtr<MCAsmParser> Parser(createMCAsmParser(SrcMgr, Ctx,
366                                                  *Str.get(), *MAI));
367  OwningPtr<MCTargetAsmParser> TAP(TheTarget->createMCAsmParser(*STI, *Parser));
368  if (!TAP) {
369    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
370    return false;
371  }
372
373  Parser->setTargetParser(*TAP.get());
374
375  bool Success = !Parser->Run(Opts.NoInitialTextSection);
376
377  // Close the output.
378  delete Out;
379
380  // Delete output on errors.
381  if (!Success && Opts.OutputPath != "-")
382    sys::Path(Opts.OutputPath).eraseFromDisk();
383
384  return Success;
385}
386
387static void LLVMErrorHandler(void *UserData, const std::string &Message,
388                             bool GenCrashDiag) {
389  DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
390
391  Diags.Report(diag::err_fe_error_backend) << Message;
392
393  // We cannot recover from llvm errors.
394  exit(1);
395}
396
397int cc1as_main(const char **ArgBegin, const char **ArgEnd,
398               const char *Argv0, void *MainAddr) {
399  // Print a stack trace if we signal out.
400  sys::PrintStackTraceOnErrorSignal();
401  PrettyStackTraceProgram X(ArgEnd - ArgBegin, ArgBegin);
402  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
403
404  // Initialize targets and assembly printers/parsers.
405  InitializeAllTargetInfos();
406  InitializeAllTargetMCs();
407  InitializeAllAsmParsers();
408
409  // Construct our diagnostic client.
410  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
411  TextDiagnosticPrinter *DiagClient
412    = new TextDiagnosticPrinter(errs(), &*DiagOpts);
413  DiagClient->setPrefix("clang -cc1as");
414  IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
415  DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagClient);
416
417  // Set an error handler, so that any LLVM backend diagnostics go through our
418  // error handler.
419  ScopedFatalErrorHandler FatalErrorHandler
420    (LLVMErrorHandler, static_cast<void*>(&Diags));
421
422  // Parse the arguments.
423  AssemblerInvocation Asm;
424  if (!AssemblerInvocation::CreateFromArgs(Asm, ArgBegin, ArgEnd, Diags))
425    return 1;
426
427  // Honor -help.
428  if (Asm.ShowHelp) {
429    OwningPtr<driver::OptTable> Opts(driver::createCC1AsOptTable());
430    Opts->PrintHelp(llvm::outs(), "clang -cc1as", "Clang Integrated Assembler");
431    return 0;
432  }
433
434  // Honor -version.
435  //
436  // FIXME: Use a better -version message?
437  if (Asm.ShowVersion) {
438    llvm::cl::PrintVersionMessage();
439    return 0;
440  }
441
442  // Honor -mllvm.
443  //
444  // FIXME: Remove this, one day.
445  if (!Asm.LLVMArgs.empty()) {
446    unsigned NumArgs = Asm.LLVMArgs.size();
447    const char **Args = new const char*[NumArgs + 2];
448    Args[0] = "clang (LLVM option parsing)";
449    for (unsigned i = 0; i != NumArgs; ++i)
450      Args[i + 1] = Asm.LLVMArgs[i].c_str();
451    Args[NumArgs + 1] = 0;
452    llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args);
453  }
454
455  // Execute the invocation, unless there were parsing errors.
456  bool Success = false;
457  if (!Diags.hasErrorOccurred())
458    Success = ExecuteAssembler(Asm, Diags);
459
460  // If any timers were active but haven't been destroyed yet, print their
461  // results now.
462  TimerGroup::printAll(errs());
463
464  return !Success;
465}
466