cc1as_main.cpp revision 27e2b983beb8b5a29869639637327725623069a8 
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/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 DebugCompilationDir;
87  std::string MainFileName;
88
89  /// @}
90  /// @name Frontend Options
91  /// @{
92
93  std::string InputFile;
94  std::vector<std::string> LLVMArgs;
95  std::string OutputPath;
96  enum FileType {
97    FT_Asm,  ///< Assembly (.s) output, transliterate mode.
98    FT_Null, ///< No output, for timing purposes.
99    FT_Obj   ///< Object file output.
100  };
101  FileType OutputType;
102  unsigned ShowHelp : 1;
103  unsigned ShowVersion : 1;
104
105  /// @}
106  /// @name Transliterate Options
107  /// @{
108
109  unsigned OutputAsmVariant;
110  unsigned ShowEncoding : 1;
111  unsigned ShowInst : 1;
112
113  /// @}
114  /// @name Assembler Options
115  /// @{
116
117  unsigned RelaxAll : 1;
118  unsigned NoExecStack : 1;
119
120  /// @}
121
122public:
123  AssemblerInvocation() {
124    Triple = "";
125    NoInitialTextSection = 0;
126    InputFile = "-";
127    OutputPath = "-";
128    OutputType = FT_Asm;
129    OutputAsmVariant = 0;
130    ShowInst = 0;
131    ShowEncoding = 0;
132    RelaxAll = 0;
133    NoExecStack = 0;
134  }
135
136  static bool CreateFromArgs(AssemblerInvocation &Res, const char **ArgBegin,
137                             const char **ArgEnd, DiagnosticsEngine &Diags);
138};
139
140}
141
142bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
143                                         const char **ArgBegin,
144                                         const char **ArgEnd,
145                                         DiagnosticsEngine &Diags) {
146  using namespace clang::driver::cc1asoptions;
147  bool Success = true;
148
149  // Parse the arguments.
150  OwningPtr<OptTable> OptTbl(createCC1AsOptTable());
151  unsigned MissingArgIndex, MissingArgCount;
152  OwningPtr<InputArgList> Args(
153    OptTbl->ParseArgs(ArgBegin, ArgEnd,MissingArgIndex, MissingArgCount));
154
155  // Check for missing argument error.
156  if (MissingArgCount) {
157    Diags.Report(diag::err_drv_missing_argument)
158      << Args->getArgString(MissingArgIndex) << MissingArgCount;
159    Success = false;
160  }
161
162  // Issue errors on unknown arguments.
163  for (arg_iterator it = Args->filtered_begin(cc1asoptions::OPT_UNKNOWN),
164         ie = Args->filtered_end(); it != ie; ++it) {
165    Diags.Report(diag::err_drv_unknown_argument) << (*it) ->getAsString(*Args);
166    Success = false;
167  }
168
169  // Construct the invocation.
170
171  // Target Options
172  Opts.Triple = llvm::Triple::normalize(Args->getLastArgValue(OPT_triple));
173  Opts.CPU = Args->getLastArgValue(OPT_target_cpu);
174  Opts.Features = Args->getAllArgValues(OPT_target_feature);
175
176  // Use the default target triple if unspecified.
177  if (Opts.Triple.empty())
178    Opts.Triple = llvm::sys::getDefaultTargetTriple();
179
180  // Language Options
181  Opts.IncludePaths = Args->getAllArgValues(OPT_I);
182  Opts.NoInitialTextSection = Args->hasArg(OPT_n);
183  Opts.SaveTemporaryLabels = Args->hasArg(OPT_L);
184  Opts.GenDwarfForAssembly = Args->hasArg(OPT_g);
185  Opts.DwarfDebugFlags = Args->getLastArgValue(OPT_dwarf_debug_flags);
186  Opts.DebugCompilationDir = Args->getLastArgValue(OPT_fdebug_compilation_dir);
187  Opts.MainFileName = Args->getLastArgValue(OPT_main_file_name);
188
189  // Frontend Options
190  if (Args->hasArg(OPT_INPUT)) {
191    bool First = true;
192    for (arg_iterator it = Args->filtered_begin(OPT_INPUT),
193           ie = Args->filtered_end(); it != ie; ++it, First=false) {
194      const Arg *A = it;
195      if (First)
196        Opts.InputFile = A->getValue();
197      else {
198        Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(*Args);
199        Success = false;
200      }
201    }
202  }
203  Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
204  if (Args->hasArg(OPT_fatal_warnings))
205    Opts.LLVMArgs.push_back("-fatal-assembler-warnings");
206  Opts.OutputPath = Args->getLastArgValue(OPT_o);
207  if (Arg *A = Args->getLastArg(OPT_filetype)) {
208    StringRef Name = A->getValue();
209    unsigned OutputType = StringSwitch<unsigned>(Name)
210      .Case("asm", FT_Asm)
211      .Case("null", FT_Null)
212      .Case("obj", FT_Obj)
213      .Default(~0U);
214    if (OutputType == ~0U) {
215      Diags.Report(diag::err_drv_invalid_value)
216        << A->getAsString(*Args) << Name;
217      Success = false;
218    } else
219      Opts.OutputType = FileType(OutputType);
220  }
221  Opts.ShowHelp = Args->hasArg(OPT_help);
222  Opts.ShowVersion = Args->hasArg(OPT_version);
223
224  // Transliterate Options
225  Opts.OutputAsmVariant = Args->getLastArgIntValue(OPT_output_asm_variant,
226                                                   0, Diags);
227  Opts.ShowEncoding = Args->hasArg(OPT_show_encoding);
228  Opts.ShowInst = Args->hasArg(OPT_show_inst);
229
230  // Assemble Options
231  Opts.RelaxAll = Args->hasArg(OPT_relax_all);
232  Opts.NoExecStack =  Args->hasArg(OPT_no_exec_stack);
233
234  return Success;
235}
236
237static formatted_raw_ostream *GetOutputStream(AssemblerInvocation &Opts,
238                                              DiagnosticsEngine &Diags,
239                                              bool Binary) {
240  if (Opts.OutputPath.empty())
241    Opts.OutputPath = "-";
242
243  // Make sure that the Out file gets unlinked from the disk if we get a
244  // SIGINT.
245  if (Opts.OutputPath != "-")
246    sys::RemoveFileOnSignal(sys::Path(Opts.OutputPath));
247
248  std::string Error;
249  raw_fd_ostream *Out =
250    new raw_fd_ostream(Opts.OutputPath.c_str(), Error,
251                       (Binary ? raw_fd_ostream::F_Binary : 0));
252  if (!Error.empty()) {
253    Diags.Report(diag::err_fe_unable_to_open_output)
254      << Opts.OutputPath << Error;
255    return 0;
256  }
257
258  return new formatted_raw_ostream(*Out, formatted_raw_ostream::DELETE_STREAM);
259}
260
261static bool ExecuteAssembler(AssemblerInvocation &Opts,
262                             DiagnosticsEngine &Diags) {
263  // Get the target specific parser.
264  std::string Error;
265  const Target *TheTarget(TargetRegistry::lookupTarget(Opts.Triple, Error));
266  if (!TheTarget) {
267    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
268    return false;
269  }
270
271  OwningPtr<MemoryBuffer> BufferPtr;
272  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Opts.InputFile, BufferPtr)) {
273    Error = ec.message();
274    Diags.Report(diag::err_fe_error_reading) << Opts.InputFile;
275    return false;
276  }
277  MemoryBuffer *Buffer = BufferPtr.take();
278
279  SourceMgr SrcMgr;
280
281  // Tell SrcMgr about this buffer, which is what the parser will pick up.
282  SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
283
284  // Record the location of the include directories so that the lexer can find
285  // it later.
286  SrcMgr.setIncludeDirs(Opts.IncludePaths);
287
288  OwningPtr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(Opts.Triple));
289  assert(MAI && "Unable to create target asm info!");
290
291  OwningPtr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
292  assert(MRI && "Unable to create target register info!");
293
294  bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
295  formatted_raw_ostream *Out = GetOutputStream(Opts, Diags, IsBinary);
296  if (!Out)
297    return false;
298
299  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
300  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
301  OwningPtr<MCObjectFileInfo> MOFI(new MCObjectFileInfo());
302  MCContext Ctx(*MAI, *MRI, MOFI.get(), &SrcMgr);
303  // FIXME: Assembler behavior can change with -static.
304  MOFI->InitMCObjectFileInfo(Opts.Triple,
305                             Reloc::Default, CodeModel::Default, Ctx);
306  if (Opts.SaveTemporaryLabels)
307    Ctx.setAllowTemporaryLabels(false);
308  if (Opts.GenDwarfForAssembly)
309    Ctx.setGenDwarfForAssembly(true);
310  if (!Opts.DwarfDebugFlags.empty())
311    Ctx.setDwarfDebugFlags(StringRef(Opts.DwarfDebugFlags));
312  if (!Opts.DebugCompilationDir.empty())
313    Ctx.setCompilationDir(Opts.DebugCompilationDir);
314  if (!Opts.MainFileName.empty())
315    Ctx.setMainFileName(StringRef(Opts.MainFileName));
316
317  // Build up the feature string from the target feature list.
318  std::string FS;
319  if (!Opts.Features.empty()) {
320    FS = Opts.Features[0];
321    for (unsigned i = 1, e = Opts.Features.size(); i != e; ++i)
322      FS += "," + Opts.Features[i];
323  }
324
325  OwningPtr<MCStreamer> Str;
326
327  OwningPtr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
328  OwningPtr<MCSubtargetInfo>
329    STI(TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
330
331  // FIXME: There is a bit of code duplication with addPassesToEmitFile.
332  if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
333    MCInstPrinter *IP =
334      TheTarget->createMCInstPrinter(Opts.OutputAsmVariant, *MAI, *MCII, *MRI,
335                                     *STI);
336    MCCodeEmitter *CE = 0;
337    MCAsmBackend *MAB = 0;
338    if (Opts.ShowEncoding) {
339      CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
340      MAB = TheTarget->createMCAsmBackend(Opts.Triple, Opts.CPU);
341    }
342    Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
343                                           /*useLoc*/ true,
344                                           /*useCFI*/ true,
345                                           /*useDwarfDirectory*/ true,
346                                           IP, CE, MAB,
347                                           Opts.ShowInst));
348  } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
349    Str.reset(createNullStreamer(Ctx));
350  } else {
351    assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
352           "Invalid file type!");
353    MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
354    MCAsmBackend *MAB = TheTarget->createMCAsmBackend(Opts.Triple, Opts.CPU);
355    Str.reset(TheTarget->createMCObjectStreamer(Opts.Triple, Ctx, *MAB, *Out,
356                                                CE, Opts.RelaxAll,
357                                                Opts.NoExecStack));
358    Str.get()->InitSections();
359  }
360
361  OwningPtr<MCAsmParser> Parser(createMCAsmParser(SrcMgr, Ctx,
362                                                  *Str.get(), *MAI));
363  OwningPtr<MCTargetAsmParser> TAP(TheTarget->createMCAsmParser(*STI, *Parser));
364  if (!TAP) {
365    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
366    return false;
367  }
368
369  Parser->setTargetParser(*TAP.get());
370
371  bool Success = !Parser->Run(Opts.NoInitialTextSection);
372
373  // Close the output.
374  delete Out;
375
376  // Delete output on errors.
377  if (!Success && Opts.OutputPath != "-")
378    sys::Path(Opts.OutputPath).eraseFromDisk();
379
380  return Success;
381}
382
383static void LLVMErrorHandler(void *UserData, const std::string &Message) {
384  DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
385
386  Diags.Report(diag::err_fe_error_backend) << Message;
387
388  // We cannot recover from llvm errors.
389  exit(1);
390}
391
392int cc1as_main(const char **ArgBegin, const char **ArgEnd,
393               const char *Argv0, void *MainAddr) {
394  // Print a stack trace if we signal out.
395  sys::PrintStackTraceOnErrorSignal();
396  PrettyStackTraceProgram X(ArgEnd - ArgBegin, ArgBegin);
397  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
398
399  // Initialize targets and assembly printers/parsers.
400  InitializeAllTargetInfos();
401  InitializeAllTargetMCs();
402  InitializeAllAsmParsers();
403
404  // Construct our diagnostic client.
405  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
406  TextDiagnosticPrinter *DiagClient
407    = new TextDiagnosticPrinter(errs(), &*DiagOpts);
408  DiagClient->setPrefix("clang -cc1as");
409  IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
410  DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagClient);
411
412  // Set an error handler, so that any LLVM backend diagnostics go through our
413  // error handler.
414  ScopedFatalErrorHandler FatalErrorHandler
415    (LLVMErrorHandler, static_cast<void*>(&Diags));
416
417  // Parse the arguments.
418  AssemblerInvocation Asm;
419  if (!AssemblerInvocation::CreateFromArgs(Asm, ArgBegin, ArgEnd, Diags))
420    return 1;
421
422  // Honor -help.
423  if (Asm.ShowHelp) {
424    OwningPtr<driver::OptTable> Opts(driver::createCC1AsOptTable());
425    Opts->PrintHelp(llvm::outs(), "clang -cc1as", "Clang Integrated Assembler");
426    return 0;
427  }
428
429  // Honor -version.
430  //
431  // FIXME: Use a better -version message?
432  if (Asm.ShowVersion) {
433    llvm::cl::PrintVersionMessage();
434    return 0;
435  }
436
437  // Honor -mllvm.
438  //
439  // FIXME: Remove this, one day.
440  if (!Asm.LLVMArgs.empty()) {
441    unsigned NumArgs = Asm.LLVMArgs.size();
442    const char **Args = new const char*[NumArgs + 2];
443    Args[0] = "clang (LLVM option parsing)";
444    for (unsigned i = 0; i != NumArgs; ++i)
445      Args[i + 1] = Asm.LLVMArgs[i].c_str();
446    Args[NumArgs + 1] = 0;
447    llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args);
448  }
449
450  // Execute the invocation, unless there were parsing errors.
451  bool Success = false;
452  if (!Diags.hasErrorOccurred())
453    Success = ExecuteAssembler(Asm, Diags);
454
455  // If any timers were active but haven't been destroyed yet, print their
456  // results now.
457  TimerGroup::printAll(errs());
458
459  return !Success;
460}
461