cc1as_main.cpp revision 2860e30d837ac361c126d4350b5d74f956160eba 
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/MCRegisterInfo.h"
34#include "llvm/MC/MCStreamer.h"
35#include "llvm/MC/MCSubtargetInfo.h"
36#include "llvm/Support/CommandLine.h"
37#include "llvm/Support/FormattedStream.h"
38#include "llvm/Support/ErrorHandling.h"
39#include "llvm/Support/ManagedStatic.h"
40#include "llvm/Support/MemoryBuffer.h"
41#include "llvm/Support/PrettyStackTrace.h"
42#include "llvm/Support/SourceMgr.h"
43#include "llvm/Support/Timer.h"
44#include "llvm/Support/raw_ostream.h"
45#include "llvm/Support/Host.h"
46#include "llvm/Support/Path.h"
47#include "llvm/Support/Signals.h"
48#include "llvm/Support/system_error.h"
49#include "llvm/Target/TargetAsmBackend.h"
50#include "llvm/Target/TargetAsmInfo.h"
51#include "llvm/Target/TargetAsmParser.h"
52#include "llvm/Target/TargetData.h"
53#include "llvm/Target/TargetInstrInfo.h"
54#include "llvm/Target/TargetLowering.h"
55#include "llvm/Target/TargetLoweringObjectFile.h"
56#include "llvm/Target/TargetMachine.h"
57#include "llvm/Target/TargetRegistry.h"
58#include "llvm/Target/TargetSelect.h"
59#include "llvm/Target/TargetSubtargetInfo.h"
60using namespace clang;
61using namespace clang::driver;
62using namespace llvm;
63
64namespace {
65
66/// \brief Helper class for representing a single invocation of the assembler.
67struct AssemblerInvocation {
68  /// @name Target Options
69  /// @{
70
71  std::string Triple;
72
73  /// @}
74  /// @name Language Options
75  /// @{
76
77  std::vector<std::string> IncludePaths;
78  unsigned NoInitialTextSection : 1;
79  unsigned SaveTemporaryLabels : 1;
80
81  /// @}
82  /// @name Frontend Options
83  /// @{
84
85  std::string InputFile;
86  std::vector<std::string> LLVMArgs;
87  std::string OutputPath;
88  enum FileType {
89    FT_Asm,  ///< Assembly (.s) output, transliterate mode.
90    FT_Null, ///< No output, for timing purposes.
91    FT_Obj   ///< Object file output.
92  };
93  FileType OutputType;
94  unsigned ShowHelp : 1;
95  unsigned ShowVersion : 1;
96
97  /// @}
98  /// @name Transliterate Options
99  /// @{
100
101  unsigned OutputAsmVariant;
102  unsigned ShowEncoding : 1;
103  unsigned ShowInst : 1;
104
105  /// @}
106  /// @name Assembler Options
107  /// @{
108
109  unsigned RelaxAll : 1;
110  unsigned NoExecStack : 1;
111
112  /// @}
113
114public:
115  AssemblerInvocation() {
116    Triple = "";
117    NoInitialTextSection = 0;
118    InputFile = "-";
119    OutputPath = "-";
120    OutputType = FT_Asm;
121    OutputAsmVariant = 0;
122    ShowInst = 0;
123    ShowEncoding = 0;
124    RelaxAll = 0;
125    NoExecStack = 0;
126  }
127
128  static void CreateFromArgs(AssemblerInvocation &Res, const char **ArgBegin,
129                             const char **ArgEnd, Diagnostic &Diags);
130};
131
132}
133
134void AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
135                                         const char **ArgBegin,
136                                         const char **ArgEnd,
137                                         Diagnostic &Diags) {
138  using namespace clang::driver::cc1asoptions;
139  // Parse the arguments.
140  OwningPtr<OptTable> OptTbl(createCC1AsOptTable());
141  unsigned MissingArgIndex, MissingArgCount;
142  OwningPtr<InputArgList> Args(
143    OptTbl->ParseArgs(ArgBegin, ArgEnd,MissingArgIndex, MissingArgCount));
144
145  // Check for missing argument error.
146  if (MissingArgCount)
147    Diags.Report(diag::err_drv_missing_argument)
148      << Args->getArgString(MissingArgIndex) << MissingArgCount;
149
150  // Issue errors on unknown arguments.
151  for (arg_iterator it = Args->filtered_begin(cc1asoptions::OPT_UNKNOWN),
152         ie = Args->filtered_end(); it != ie; ++it)
153    Diags.Report(diag::err_drv_unknown_argument) << (*it) ->getAsString(*Args);
154
155  // Construct the invocation.
156
157  // Target Options
158  Opts.Triple = Triple::normalize(Args->getLastArgValue(OPT_triple));
159  if (Opts.Triple.empty()) // Use the host triple if unspecified.
160    Opts.Triple = sys::getHostTriple();
161
162  // Language Options
163  Opts.IncludePaths = Args->getAllArgValues(OPT_I);
164  Opts.NoInitialTextSection = Args->hasArg(OPT_n);
165  Opts.SaveTemporaryLabels = Args->hasArg(OPT_L);
166
167  // Frontend Options
168  if (Args->hasArg(OPT_INPUT)) {
169    bool First = true;
170    for (arg_iterator it = Args->filtered_begin(OPT_INPUT),
171           ie = Args->filtered_end(); it != ie; ++it, First=false) {
172      const Arg *A = it;
173      if (First)
174        Opts.InputFile = A->getValue(*Args);
175      else
176        Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(*Args);
177    }
178  }
179  Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
180  if (Args->hasArg(OPT_fatal_warnings))
181    Opts.LLVMArgs.push_back("-fatal-assembler-warnings");
182  Opts.OutputPath = Args->getLastArgValue(OPT_o);
183  if (Arg *A = Args->getLastArg(OPT_filetype)) {
184    StringRef Name = A->getValue(*Args);
185    unsigned OutputType = StringSwitch<unsigned>(Name)
186      .Case("asm", FT_Asm)
187      .Case("null", FT_Null)
188      .Case("obj", FT_Obj)
189      .Default(~0U);
190    if (OutputType == ~0U)
191      Diags.Report(diag::err_drv_invalid_value)
192        << A->getAsString(*Args) << Name;
193    else
194      Opts.OutputType = FileType(OutputType);
195  }
196  Opts.ShowHelp = Args->hasArg(OPT_help);
197  Opts.ShowVersion = Args->hasArg(OPT_version);
198
199  // Transliterate Options
200  Opts.OutputAsmVariant = Args->getLastArgIntValue(OPT_output_asm_variant,
201                                                   0, Diags);
202  Opts.ShowEncoding = Args->hasArg(OPT_show_encoding);
203  Opts.ShowInst = Args->hasArg(OPT_show_inst);
204
205  // Assemble Options
206  Opts.RelaxAll = Args->hasArg(OPT_relax_all);
207  Opts.NoExecStack =  Args->hasArg(OPT_no_exec_stack);
208}
209
210static formatted_raw_ostream *GetOutputStream(AssemblerInvocation &Opts,
211                                              Diagnostic &Diags,
212                                              bool Binary) {
213  if (Opts.OutputPath.empty())
214    Opts.OutputPath = "-";
215
216  // Make sure that the Out file gets unlinked from the disk if we get a
217  // SIGINT.
218  if (Opts.OutputPath != "-")
219    sys::RemoveFileOnSignal(sys::Path(Opts.OutputPath));
220
221  std::string Error;
222  raw_fd_ostream *Out =
223    new raw_fd_ostream(Opts.OutputPath.c_str(), Error,
224                       (Binary ? raw_fd_ostream::F_Binary : 0));
225  if (!Error.empty()) {
226    Diags.Report(diag::err_fe_unable_to_open_output)
227      << Opts.OutputPath << Error;
228    return 0;
229  }
230
231  return new formatted_raw_ostream(*Out, formatted_raw_ostream::DELETE_STREAM);
232}
233
234static bool ExecuteAssembler(AssemblerInvocation &Opts, Diagnostic &Diags) {
235  // Get the target specific parser.
236  std::string Error;
237  const Target *TheTarget(TargetRegistry::lookupTarget(Opts.Triple, Error));
238  if (!TheTarget) {
239    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
240    return false;
241  }
242
243  OwningPtr<MemoryBuffer> BufferPtr;
244  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Opts.InputFile, BufferPtr)) {
245    Error = ec.message();
246    Diags.Report(diag::err_fe_error_reading) << Opts.InputFile;
247    return false;
248  }
249  MemoryBuffer *Buffer = BufferPtr.take();
250
251  SourceMgr SrcMgr;
252
253  // Tell SrcMgr about this buffer, which is what the parser will pick up.
254  SrcMgr.AddNewSourceBuffer(Buffer, SMLoc());
255
256  // Record the location of the include directories so that the lexer can find
257  // it later.
258  SrcMgr.setIncludeDirs(Opts.IncludePaths);
259
260  OwningPtr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(Opts.Triple));
261  assert(MAI && "Unable to create target asm info!");
262
263  OwningPtr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
264  assert(MRI && "Unable to create target register info!");
265
266  bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
267  formatted_raw_ostream *Out = GetOutputStream(Opts, Diags, IsBinary);
268  if (!Out)
269    return false;
270
271  // FIXME: We shouldn't need to do this (and link in codegen).
272  OwningPtr<TargetMachine> TM(TheTarget->createTargetMachine(Opts.Triple,
273                                                             "", ""));
274  if (!TM) {
275    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
276    return false;
277  }
278
279  const TargetAsmInfo *tai = new TargetAsmInfo(*TM);
280  MCContext Ctx(*MAI, *MRI, tai);
281  if (Opts.SaveTemporaryLabels)
282    Ctx.setAllowTemporaryLabels(false);
283
284  OwningPtr<MCStreamer> Str;
285
286  const TargetLoweringObjectFile &TLOF =
287    TM->getTargetLowering()->getObjFileLowering();
288  const_cast<TargetLoweringObjectFile&>(TLOF).Initialize(Ctx, *TM);
289
290  const MCSubtargetInfo &STI = TM->getSubtarget<MCSubtargetInfo>();
291
292  // FIXME: There is a bit of code duplication with addPassesToEmitFile.
293  if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
294    MCInstPrinter *IP =
295      TheTarget->createMCInstPrinter(Opts.OutputAsmVariant, *MAI);
296    MCCodeEmitter *CE = 0;
297    TargetAsmBackend *TAB = 0;
298    if (Opts.ShowEncoding) {
299      CE = TheTarget->createCodeEmitter(*TM->getInstrInfo(), STI, Ctx);
300      TAB = TheTarget->createAsmBackend(Opts.Triple);
301    }
302    Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
303                                           /*useLoc*/ true,
304                                           /*useCFI*/ true, IP, CE, TAB,
305                                           Opts.ShowInst));
306  } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
307    Str.reset(createNullStreamer(Ctx));
308  } else {
309    assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
310           "Invalid file type!");
311    MCCodeEmitter *CE = TheTarget->createCodeEmitter(*TM->getInstrInfo(),
312                                                     STI, Ctx);
313    TargetAsmBackend *TAB = TheTarget->createAsmBackend(Opts.Triple);
314    Str.reset(TheTarget->createObjectStreamer(Opts.Triple, Ctx, *TAB, *Out,
315                                              CE, Opts.RelaxAll,
316                                              Opts.NoExecStack));
317    Str.get()->InitSections();
318  }
319
320  OwningPtr<MCAsmParser> Parser(createMCAsmParser(*TheTarget, SrcMgr, Ctx,
321                                                  *Str.get(), *MAI));
322  OwningPtr<TargetAsmParser>
323    TAP(TheTarget->createAsmParser(const_cast<MCSubtargetInfo&>(STI), *Parser));
324  if (!TAP) {
325    Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
326    return false;
327  }
328
329  Parser->setTargetParser(*TAP.get());
330
331  bool Success = !Parser->Run(Opts.NoInitialTextSection);
332
333  // Close the output.
334  delete Out;
335
336  // Delete output on errors.
337  if (!Success && Opts.OutputPath != "-")
338    sys::Path(Opts.OutputPath).eraseFromDisk();
339
340  return Success;
341}
342
343static void LLVMErrorHandler(void *UserData, const std::string &Message) {
344  Diagnostic &Diags = *static_cast<Diagnostic*>(UserData);
345
346  Diags.Report(diag::err_fe_error_backend) << Message;
347
348  // We cannot recover from llvm errors.
349  exit(1);
350}
351
352int cc1as_main(const char **ArgBegin, const char **ArgEnd,
353               const char *Argv0, void *MainAddr) {
354  // Print a stack trace if we signal out.
355  sys::PrintStackTraceOnErrorSignal();
356  PrettyStackTraceProgram X(ArgEnd - ArgBegin, ArgBegin);
357  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
358
359  // Initialize targets and assembly printers/parsers.
360  InitializeAllTargetInfos();
361  // FIXME: We shouldn't need to initialize the Target(Machine)s.
362  InitializeAllTargets();
363  InitializeAllMCAsmInfos();
364  InitializeAllMCCodeGenInfos();
365  InitializeAllMCInstrInfos();
366  InitializeAllMCRegisterInfos();
367  InitializeAllMCSubtargetInfos();
368  InitializeAllAsmPrinters();
369  InitializeAllAsmParsers();
370
371  // Construct our diagnostic client.
372  TextDiagnosticPrinter *DiagClient
373    = new TextDiagnosticPrinter(errs(), DiagnosticOptions());
374  DiagClient->setPrefix("clang -cc1as");
375  llvm::IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
376  Diagnostic Diags(DiagID, DiagClient);
377
378  // Set an error handler, so that any LLVM backend diagnostics go through our
379  // error handler.
380  ScopedFatalErrorHandler FatalErrorHandler
381    (LLVMErrorHandler, static_cast<void*>(&Diags));
382
383  // Parse the arguments.
384  AssemblerInvocation Asm;
385  AssemblerInvocation::CreateFromArgs(Asm, ArgBegin, ArgEnd, Diags);
386
387  // Honor -help.
388  if (Asm.ShowHelp) {
389    llvm::OwningPtr<driver::OptTable> Opts(driver::createCC1AsOptTable());
390    Opts->PrintHelp(llvm::outs(), "clang -cc1as", "Clang Integrated Assembler");
391    return 0;
392  }
393
394  // Honor -version.
395  //
396  // FIXME: Use a better -version message?
397  if (Asm.ShowVersion) {
398    llvm::cl::PrintVersionMessage();
399    return 0;
400  }
401
402  // Honor -mllvm.
403  //
404  // FIXME: Remove this, one day.
405  if (!Asm.LLVMArgs.empty()) {
406    unsigned NumArgs = Asm.LLVMArgs.size();
407    const char **Args = new const char*[NumArgs + 2];
408    Args[0] = "clang (LLVM option parsing)";
409    for (unsigned i = 0; i != NumArgs; ++i)
410      Args[i + 1] = Asm.LLVMArgs[i].c_str();
411    Args[NumArgs + 1] = 0;
412    llvm::cl::ParseCommandLineOptions(NumArgs + 1, const_cast<char **>(Args));
413  }
414
415  // Execute the invocation, unless there were parsing errors.
416  bool Success = false;
417  if (!Diags.hasErrorOccurred())
418    Success = ExecuteAssembler(Asm, Diags);
419
420  // If any timers were active but haven't been destroyed yet, print their
421  // results now.
422  TimerGroup::printAll(errs());
423
424  return !Success;
425}
426