xref: /minix3/external/bsd/llvm/dist/clang/tools/driver/cc1as_main.cpp (revision bdb565187c0f1a04513dd488df843317b27f86c8) 
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/DriverDiagnostic.h"
18 #include "clang/Driver/Options.h"
19 #include "clang/Frontend/FrontendDiagnostic.h"
20 #include "clang/Frontend/TextDiagnosticPrinter.h"
21 #include "clang/Frontend/Utils.h"
22 #include "llvm/ADT/StringSwitch.h"
23 #include "llvm/ADT/Triple.h"
24 #include "llvm/IR/DataLayout.h"
25 #include "llvm/MC/MCAsmBackend.h"
26 #include "llvm/MC/MCAsmInfo.h"
27 #include "llvm/MC/MCCodeEmitter.h"
28 #include "llvm/MC/MCContext.h"
29 #include "llvm/MC/MCInstrInfo.h"
30 #include "llvm/MC/MCObjectFileInfo.h"
31 #include "llvm/MC/MCParser/MCAsmParser.h"
32 #include "llvm/MC/MCRegisterInfo.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/MC/MCSubtargetInfo.h"
35 #include "llvm/MC/MCTargetAsmParser.h"
36 #include "llvm/MC/MCTargetOptions.h"
37 #include "llvm/Option/Arg.h"
38 #include "llvm/Option/ArgList.h"
39 #include "llvm/Option/OptTable.h"
40 #include "llvm/Support/CommandLine.h"
41 #include "llvm/Support/ErrorHandling.h"
42 #include "llvm/Support/FileSystem.h"
43 #include "llvm/Support/FormattedStream.h"
44 #include "llvm/Support/Host.h"
45 #include "llvm/Support/ManagedStatic.h"
46 #include "llvm/Support/MemoryBuffer.h"
47 #include "llvm/Support/Path.h"
48 #include "llvm/Support/PrettyStackTrace.h"
49 #include "llvm/Support/Signals.h"
50 #include "llvm/Support/SourceMgr.h"
51 #include "llvm/Support/TargetRegistry.h"
52 #include "llvm/Support/TargetSelect.h"
53 #include "llvm/Support/Timer.h"
54 #include "llvm/Support/raw_ostream.h"
55 #include <memory>
56 #include <system_error>
57 using namespace clang;
58 using namespace clang::driver;
59 using namespace clang::driver::options;
60 using namespace llvm;
61 using namespace llvm::opt;
62 
63 namespace {
64 
65 /// \brief Helper class for representing a single invocation of the assembler.
66 struct AssemblerInvocation {
67   /// @name Target Options
68   /// @{
69 
70   /// The name of the target triple to assemble for.
71   std::string Triple;
72 
73   /// If given, the name of the target CPU to determine which instructions
74   /// are legal.
75   std::string CPU;
76 
77   /// The list of target specific features to enable or disable -- this should
78   /// be a list of strings starting with '+' or '-'.
79   std::vector<std::string> Features;
80 
81   /// @}
82   /// @name Language Options
83   /// @{
84 
85   std::vector<std::string> IncludePaths;
86   unsigned NoInitialTextSection : 1;
87   unsigned SaveTemporaryLabels : 1;
88   unsigned GenDwarfForAssembly : 1;
89   unsigned CompressDebugSections : 1;
90   unsigned DwarfVersion;
91   std::string DwarfDebugFlags;
92   std::string DwarfDebugProducer;
93   std::string DebugCompilationDir;
94   std::string MainFileName;
95 
96   /// @}
97   /// @name Frontend Options
98   /// @{
99 
100   std::string InputFile;
101   std::vector<std::string> LLVMArgs;
102   std::string OutputPath;
103   enum FileType {
104     FT_Asm,  ///< Assembly (.s) output, transliterate mode.
105     FT_Null, ///< No output, for timing purposes.
106     FT_Obj   ///< Object file output.
107   };
108   FileType OutputType;
109   unsigned ShowHelp : 1;
110   unsigned ShowVersion : 1;
111 
112   /// @}
113   /// @name Transliterate Options
114   /// @{
115 
116   unsigned OutputAsmVariant;
117   unsigned ShowEncoding : 1;
118   unsigned ShowInst : 1;
119 
120   /// @}
121   /// @name Assembler Options
122   /// @{
123 
124   unsigned RelaxAll : 1;
125   unsigned NoExecStack : 1;
126   unsigned FatalWarnings : 1;
127 
128   /// @}
129 
130 public:
131   AssemblerInvocation() {
132     Triple = "";
133     NoInitialTextSection = 0;
134     InputFile = "-";
135     OutputPath = "-";
136     OutputType = FT_Asm;
137     OutputAsmVariant = 0;
138     ShowInst = 0;
139     ShowEncoding = 0;
140     RelaxAll = 0;
141     NoExecStack = 0;
142     FatalWarnings = 0;
143     DwarfVersion = 3;
144   }
145 
146   static bool CreateFromArgs(AssemblerInvocation &Res,
147                              ArrayRef<const char *> Argv,
148                              DiagnosticsEngine &Diags);
149 };
150 
151 }
152 
153 bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
154                                          ArrayRef<const char *> Argv,
155                                          DiagnosticsEngine &Diags) {
156   bool Success = true;
157 
158   // Parse the arguments.
159   std::unique_ptr<OptTable> OptTbl(createDriverOptTable());
160 
161   const unsigned IncludedFlagsBitmask = options::CC1AsOption;
162   unsigned MissingArgIndex, MissingArgCount;
163   std::unique_ptr<InputArgList> Args(
164       OptTbl->ParseArgs(Argv.begin(), Argv.end(), MissingArgIndex, MissingArgCount,
165                         IncludedFlagsBitmask));
166 
167   // Check for missing argument error.
168   if (MissingArgCount) {
169     Diags.Report(diag::err_drv_missing_argument)
170         << Args->getArgString(MissingArgIndex) << MissingArgCount;
171     Success = false;
172   }
173 
174   // Issue errors on unknown arguments.
175   for (arg_iterator it = Args->filtered_begin(OPT_UNKNOWN),
176                     ie = Args->filtered_end();
177        it != ie; ++it) {
178     Diags.Report(diag::err_drv_unknown_argument) << (*it)->getAsString(*Args);
179     Success = false;
180   }
181 
182   // Construct the invocation.
183 
184   // Target Options
185   Opts.Triple = llvm::Triple::normalize(Args->getLastArgValue(OPT_triple));
186   Opts.CPU = Args->getLastArgValue(OPT_target_cpu);
187   Opts.Features = Args->getAllArgValues(OPT_target_feature);
188 
189   // Use the default target triple if unspecified.
190   if (Opts.Triple.empty())
191     Opts.Triple = llvm::sys::getDefaultTargetTriple();
192 
193   // Language Options
194   Opts.IncludePaths = Args->getAllArgValues(OPT_I);
195   Opts.NoInitialTextSection = Args->hasArg(OPT_n);
196   Opts.SaveTemporaryLabels = Args->hasArg(OPT_msave_temp_labels);
197   Opts.GenDwarfForAssembly = Args->hasArg(OPT_g_Flag);
198   Opts.CompressDebugSections = Args->hasArg(OPT_compress_debug_sections);
199   if (Args->hasArg(OPT_gdwarf_2))
200     Opts.DwarfVersion = 2;
201   if (Args->hasArg(OPT_gdwarf_3))
202     Opts.DwarfVersion = 3;
203   if (Args->hasArg(OPT_gdwarf_4))
204     Opts.DwarfVersion = 4;
205   Opts.DwarfDebugFlags = Args->getLastArgValue(OPT_dwarf_debug_flags);
206   Opts.DwarfDebugProducer = Args->getLastArgValue(OPT_dwarf_debug_producer);
207   Opts.DebugCompilationDir = Args->getLastArgValue(OPT_fdebug_compilation_dir);
208   Opts.MainFileName = Args->getLastArgValue(OPT_main_file_name);
209 
210   // Frontend Options
211   if (Args->hasArg(OPT_INPUT)) {
212     bool First = true;
213     for (arg_iterator it = Args->filtered_begin(OPT_INPUT),
214            ie = Args->filtered_end(); it != ie; ++it, First=false) {
215       const Arg *A = it;
216       if (First)
217         Opts.InputFile = A->getValue();
218       else {
219         Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(*Args);
220         Success = false;
221       }
222     }
223   }
224   Opts.LLVMArgs = Args->getAllArgValues(OPT_mllvm);
225   Opts.OutputPath = Args->getLastArgValue(OPT_o);
226   if (Arg *A = Args->getLastArg(OPT_filetype)) {
227     StringRef Name = A->getValue();
228     unsigned OutputType = StringSwitch<unsigned>(Name)
229       .Case("asm", FT_Asm)
230       .Case("null", FT_Null)
231       .Case("obj", FT_Obj)
232       .Default(~0U);
233     if (OutputType == ~0U) {
234       Diags.Report(diag::err_drv_invalid_value)
235         << A->getAsString(*Args) << Name;
236       Success = false;
237     } else
238       Opts.OutputType = FileType(OutputType);
239   }
240   Opts.ShowHelp = Args->hasArg(OPT_help);
241   Opts.ShowVersion = Args->hasArg(OPT_version);
242 
243   // Transliterate Options
244   Opts.OutputAsmVariant =
245       getLastArgIntValue(*Args.get(), OPT_output_asm_variant, 0, Diags);
246   Opts.ShowEncoding = Args->hasArg(OPT_show_encoding);
247   Opts.ShowInst = Args->hasArg(OPT_show_inst);
248 
249   // Assemble Options
250   Opts.RelaxAll = Args->hasArg(OPT_mrelax_all);
251   Opts.NoExecStack = Args->hasArg(OPT_mno_exec_stack);
252   Opts.FatalWarnings =  Args->hasArg(OPT_massembler_fatal_warnings);
253 
254   return Success;
255 }
256 
257 static formatted_raw_ostream *GetOutputStream(AssemblerInvocation &Opts,
258                                               DiagnosticsEngine &Diags,
259                                               bool Binary) {
260   if (Opts.OutputPath.empty())
261     Opts.OutputPath = "-";
262 
263   // Make sure that the Out file gets unlinked from the disk if we get a
264   // SIGINT.
265   if (Opts.OutputPath != "-")
266     sys::RemoveFileOnSignal(Opts.OutputPath);
267 
268   std::error_code EC;
269   raw_fd_ostream *Out = new raw_fd_ostream(
270       Opts.OutputPath, EC, (Binary ? sys::fs::F_None : sys::fs::F_Text));
271   if (EC) {
272     Diags.Report(diag::err_fe_unable_to_open_output) << Opts.OutputPath
273                                                      << EC.message();
274     delete Out;
275     return nullptr;
276   }
277 
278   return new formatted_raw_ostream(*Out, formatted_raw_ostream::DELETE_STREAM);
279 }
280 
281 static bool ExecuteAssembler(AssemblerInvocation &Opts,
282                              DiagnosticsEngine &Diags) {
283   // Get the target specific parser.
284   std::string Error;
285   const Target *TheTarget = TargetRegistry::lookupTarget(Opts.Triple, Error);
286   if (!TheTarget)
287     return Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
288 
289   ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
290       MemoryBuffer::getFileOrSTDIN(Opts.InputFile);
291 
292   if (std::error_code EC = Buffer.getError()) {
293     Error = EC.message();
294     return Diags.Report(diag::err_fe_error_reading) << Opts.InputFile;
295   }
296 
297   SourceMgr SrcMgr;
298 
299   // Tell SrcMgr about this buffer, which is what the parser will pick up.
300   SrcMgr.AddNewSourceBuffer(std::move(*Buffer), SMLoc());
301 
302   // Record the location of the include directories so that the lexer can find
303   // it later.
304   SrcMgr.setIncludeDirs(Opts.IncludePaths);
305 
306   std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
307   assert(MRI && "Unable to create target register info!");
308 
309   std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, Opts.Triple));
310   assert(MAI && "Unable to create target asm info!");
311 
312   // Ensure MCAsmInfo initialization occurs before any use, otherwise sections
313   // may be created with a combination of default and explicit settings.
314   if (Opts.CompressDebugSections)
315     MAI->setCompressDebugSections(true);
316 
317   bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
318   std::unique_ptr<formatted_raw_ostream> Out(
319       GetOutputStream(Opts, Diags, IsBinary));
320   if (!Out)
321     return true;
322 
323   // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
324   // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
325   std::unique_ptr<MCObjectFileInfo> MOFI(new MCObjectFileInfo());
326 
327   MCContext Ctx(MAI.get(), MRI.get(), MOFI.get(), &SrcMgr);
328   // FIXME: Assembler behavior can change with -static.
329   MOFI->InitMCObjectFileInfo(Opts.Triple,
330                              Reloc::Default, CodeModel::Default, Ctx);
331   if (Opts.SaveTemporaryLabels)
332     Ctx.setAllowTemporaryLabels(false);
333   if (Opts.GenDwarfForAssembly)
334     Ctx.setGenDwarfForAssembly(true);
335   if (!Opts.DwarfDebugFlags.empty())
336     Ctx.setDwarfDebugFlags(StringRef(Opts.DwarfDebugFlags));
337   if (!Opts.DwarfDebugProducer.empty())
338     Ctx.setDwarfDebugProducer(StringRef(Opts.DwarfDebugProducer));
339   if (!Opts.DebugCompilationDir.empty())
340     Ctx.setCompilationDir(Opts.DebugCompilationDir);
341   if (!Opts.MainFileName.empty())
342     Ctx.setMainFileName(StringRef(Opts.MainFileName));
343   Ctx.setDwarfVersion(Opts.DwarfVersion);
344 
345   // Build up the feature string from the target feature list.
346   std::string FS;
347   if (!Opts.Features.empty()) {
348     FS = Opts.Features[0];
349     for (unsigned i = 1, e = Opts.Features.size(); i != e; ++i)
350       FS += "," + Opts.Features[i];
351   }
352 
353   std::unique_ptr<MCStreamer> Str;
354 
355   std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
356   std::unique_ptr<MCSubtargetInfo> STI(
357       TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
358 
359   // FIXME: There is a bit of code duplication with addPassesToEmitFile.
360   if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
361     MCInstPrinter *IP =
362       TheTarget->createMCInstPrinter(Opts.OutputAsmVariant, *MAI, *MCII, *MRI,
363                                      *STI);
364     MCCodeEmitter *CE = nullptr;
365     MCAsmBackend *MAB = nullptr;
366     if (Opts.ShowEncoding) {
367       CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
368       MAB = TheTarget->createMCAsmBackend(*MRI, Opts.Triple, Opts.CPU);
369     }
370     Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
371                                            /*useDwarfDirectory*/ true,
372                                            IP, CE, MAB,
373                                            Opts.ShowInst));
374   } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
375     Str.reset(createNullStreamer(Ctx));
376   } else {
377     assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
378            "Invalid file type!");
379     MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
380     MCAsmBackend *MAB = TheTarget->createMCAsmBackend(*MRI, Opts.Triple,
381                                                       Opts.CPU);
382     Str.reset(TheTarget->createMCObjectStreamer(Opts.Triple, Ctx, *MAB, *Out,
383                                                 CE, *STI, Opts.RelaxAll));
384     Str.get()->InitSections(Opts.NoExecStack);
385   }
386 
387   bool Failed = false;
388 
389   std::unique_ptr<MCAsmParser> Parser(
390       createMCAsmParser(SrcMgr, Ctx, *Str.get(), *MAI));
391 
392   // FIXME: init MCTargetOptions from sanitizer flags here.
393   MCTargetOptions Options;
394   std::unique_ptr<MCTargetAsmParser> TAP(
395       TheTarget->createMCAsmParser(*STI, *Parser, *MCII, Options));
396   if (!TAP)
397     Failed = Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
398 
399   if (!Failed) {
400     Parser->setTargetParser(*TAP.get());
401     Failed = Parser->Run(Opts.NoInitialTextSection);
402   }
403 
404   // Close the output stream early.
405   Out.reset();
406 
407   // Delete output file if there were errors.
408   if (Failed && Opts.OutputPath != "-")
409     sys::fs::remove(Opts.OutputPath);
410 
411   return Failed;
412 }
413 
414 static void LLVMErrorHandler(void *UserData, const std::string &Message,
415                              bool GenCrashDiag) {
416   DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
417 
418   Diags.Report(diag::err_fe_error_backend) << Message;
419 
420   // We cannot recover from llvm errors.
421   exit(1);
422 }
423 
424 int cc1as_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
425   // Print a stack trace if we signal out.
426   sys::PrintStackTraceOnErrorSignal();
427   PrettyStackTraceProgram X(Argv.size(), Argv.data());
428   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
429 
430   // Initialize targets and assembly printers/parsers.
431   InitializeAllTargetInfos();
432   InitializeAllTargetMCs();
433   InitializeAllAsmParsers();
434 
435   // Construct our diagnostic client.
436   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
437   TextDiagnosticPrinter *DiagClient
438     = new TextDiagnosticPrinter(errs(), &*DiagOpts);
439   DiagClient->setPrefix("clang -cc1as");
440   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
441   DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagClient);
442 
443   // Set an error handler, so that any LLVM backend diagnostics go through our
444   // error handler.
445   ScopedFatalErrorHandler FatalErrorHandler
446     (LLVMErrorHandler, static_cast<void*>(&Diags));
447 
448   // Parse the arguments.
449   AssemblerInvocation Asm;
450   if (!AssemblerInvocation::CreateFromArgs(Asm, Argv, Diags))
451     return 1;
452 
453   if (Asm.ShowHelp) {
454     std::unique_ptr<OptTable> Opts(driver::createDriverOptTable());
455     Opts->PrintHelp(llvm::outs(), "clang -cc1as", "Clang Integrated Assembler",
456                     /*Include=*/driver::options::CC1AsOption, /*Exclude=*/0);
457     return 0;
458   }
459 
460   // Honor -version.
461   //
462   // FIXME: Use a better -version message?
463   if (Asm.ShowVersion) {
464     llvm::cl::PrintVersionMessage();
465     return 0;
466   }
467 
468   // Honor -mllvm.
469   //
470   // FIXME: Remove this, one day.
471   if (!Asm.LLVMArgs.empty()) {
472     unsigned NumArgs = Asm.LLVMArgs.size();
473     const char **Args = new const char*[NumArgs + 2];
474     Args[0] = "clang (LLVM option parsing)";
475     for (unsigned i = 0; i != NumArgs; ++i)
476       Args[i + 1] = Asm.LLVMArgs[i].c_str();
477     Args[NumArgs + 1] = nullptr;
478     llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args);
479   }
480 
481   // Execute the invocation, unless there were parsing errors.
482   bool Failed = Diags.hasErrorOccurred() || ExecuteAssembler(Asm, Diags);
483 
484   // If any timers were active but haven't been destroyed yet, print their
485   // results now.
486   TimerGroup::printAll(errs());
487 
488   return !!Failed;
489 }
490 
491