1 //===-- llvm-ml.cpp - masm-compatible assembler -----------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // A simple driver around MasmParser; based on llvm-mc.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/ADT/StringSwitch.h"
14 #include "llvm/MC/MCAsmBackend.h"
15 #include "llvm/MC/MCAsmInfo.h"
16 #include "llvm/MC/MCCodeEmitter.h"
17 #include "llvm/MC/MCContext.h"
18 #include "llvm/MC/MCInstPrinter.h"
19 #include "llvm/MC/MCInstrInfo.h"
20 #include "llvm/MC/MCObjectFileInfo.h"
21 #include "llvm/MC/MCObjectWriter.h"
22 #include "llvm/MC/MCParser/AsmLexer.h"
23 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
24 #include "llvm/MC/MCRegisterInfo.h"
25 #include "llvm/MC/MCStreamer.h"
26 #include "llvm/MC/MCSubtargetInfo.h"
27 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
28 #include "llvm/MC/TargetRegistry.h"
29 #include "llvm/Option/Arg.h"
30 #include "llvm/Option/ArgList.h"
31 #include "llvm/Option/Option.h"
32 #include "llvm/Support/Compression.h"
33 #include "llvm/Support/FileUtilities.h"
34 #include "llvm/Support/FormatVariadic.h"
35 #include "llvm/Support/FormattedStream.h"
36 #include "llvm/Support/Host.h"
37 #include "llvm/Support/InitLLVM.h"
38 #include "llvm/Support/MemoryBuffer.h"
39 #include "llvm/Support/Path.h"
40 #include "llvm/Support/Process.h"
41 #include "llvm/Support/SourceMgr.h"
42 #include "llvm/Support/TargetSelect.h"
43 #include "llvm/Support/ToolOutputFile.h"
44 #include "llvm/Support/WithColor.h"
45 #include <ctime>
46 
47 using namespace llvm;
48 using namespace llvm::opt;
49 
50 namespace {
51 
52 enum ID {
53   OPT_INVALID = 0, // This is not an option ID.
54 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
55                HELPTEXT, METAVAR, VALUES)                                      \
56   OPT_##ID,
57 #include "Opts.inc"
58 #undef OPTION
59 };
60 
61 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
62 #include "Opts.inc"
63 #undef PREFIX
64 
65 const opt::OptTable::Info InfoTable[] = {
66 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
67                HELPTEXT, METAVAR, VALUES)                                      \
68   {                                                                            \
69       PREFIX,      NAME,      HELPTEXT,                                        \
70       METAVAR,     OPT_##ID,  opt::Option::KIND##Class,                        \
71       PARAM,       FLAGS,     OPT_##GROUP,                                     \
72       OPT_##ALIAS, ALIASARGS, VALUES},
73 #include "Opts.inc"
74 #undef OPTION
75 };
76 
77 class MLOptTable : public opt::OptTable {
78 public:
79   MLOptTable() : OptTable(InfoTable, /*IgnoreCase=*/false) {}
80 };
81 } // namespace
82 
83 static Triple GetTriple(StringRef ProgName, opt::InputArgList &Args) {
84   // Figure out the target triple.
85   StringRef DefaultBitness = "32";
86   SmallString<255> Program = ProgName;
87   sys::path::replace_extension(Program, "");
88   if (Program.endswith("ml64"))
89     DefaultBitness = "64";
90 
91   StringRef TripleName =
92       StringSwitch<StringRef>(Args.getLastArgValue(OPT_bitness, DefaultBitness))
93           .Case("32", "i386-pc-windows")
94           .Case("64", "x86_64-pc-windows")
95           .Default("");
96   return Triple(Triple::normalize(TripleName));
97 }
98 
99 static std::unique_ptr<ToolOutputFile> GetOutputStream(StringRef Path) {
100   std::error_code EC;
101   auto Out = std::make_unique<ToolOutputFile>(Path, EC, sys::fs::OF_None);
102   if (EC) {
103     WithColor::error() << EC.message() << '\n';
104     return nullptr;
105   }
106 
107   return Out;
108 }
109 
110 static int AsLexInput(SourceMgr &SrcMgr, MCAsmInfo &MAI, raw_ostream &OS) {
111   AsmLexer Lexer(MAI);
112   Lexer.setBuffer(SrcMgr.getMemoryBuffer(SrcMgr.getMainFileID())->getBuffer());
113   Lexer.setLexMasmIntegers(true);
114   Lexer.useMasmDefaultRadix(true);
115   Lexer.setLexMasmHexFloats(true);
116   Lexer.setLexMasmStrings(true);
117 
118   bool Error = false;
119   while (Lexer.Lex().isNot(AsmToken::Eof)) {
120     Lexer.getTok().dump(OS);
121     OS << "\n";
122     if (Lexer.getTok().getKind() == AsmToken::Error)
123       Error = true;
124   }
125 
126   return Error;
127 }
128 
129 static int AssembleInput(StringRef ProgName, const Target *TheTarget,
130                          SourceMgr &SrcMgr, MCContext &Ctx, MCStreamer &Str,
131                          MCAsmInfo &MAI, MCSubtargetInfo &STI,
132                          MCInstrInfo &MCII, MCTargetOptions &MCOptions,
133                          const opt::ArgList &InputArgs) {
134   struct tm TM;
135   time_t Timestamp;
136   if (InputArgs.hasArg(OPT_timestamp)) {
137     StringRef TimestampStr = InputArgs.getLastArgValue(OPT_timestamp);
138     int64_t IntTimestamp;
139     if (TimestampStr.getAsInteger(10, IntTimestamp)) {
140       WithColor::error(errs(), ProgName)
141           << "invalid timestamp '" << TimestampStr
142           << "'; must be expressed in seconds since the UNIX epoch.\n";
143       return 1;
144     }
145     Timestamp = IntTimestamp;
146   } else {
147     Timestamp = time(nullptr);
148   }
149   if (InputArgs.hasArg(OPT_utc)) {
150     // Not thread-safe.
151     TM = *gmtime(&Timestamp);
152   } else {
153     // Not thread-safe.
154     TM = *localtime(&Timestamp);
155   }
156 
157   std::unique_ptr<MCAsmParser> Parser(
158       createMCMasmParser(SrcMgr, Ctx, Str, MAI, TM, 0));
159   std::unique_ptr<MCTargetAsmParser> TAP(
160       TheTarget->createMCAsmParser(STI, *Parser, MCII, MCOptions));
161 
162   if (!TAP) {
163     WithColor::error(errs(), ProgName)
164         << "this target does not support assembly parsing.\n";
165     return 1;
166   }
167 
168   Parser->setShowParsedOperands(InputArgs.hasArg(OPT_show_inst_operands));
169   Parser->setTargetParser(*TAP);
170   Parser->getLexer().setLexMasmIntegers(true);
171   Parser->getLexer().useMasmDefaultRadix(true);
172   Parser->getLexer().setLexMasmHexFloats(true);
173   Parser->getLexer().setLexMasmStrings(true);
174 
175   auto Defines = InputArgs.getAllArgValues(OPT_define);
176   for (StringRef Define : Defines) {
177     const auto NameValue = Define.split('=');
178     StringRef Name = NameValue.first, Value = NameValue.second;
179     if (Parser->defineMacro(Name, Value)) {
180       WithColor::error(errs(), ProgName)
181           << "can't define macro '" << Name << "' = '" << Value << "'\n";
182       return 1;
183     }
184   }
185 
186   int Res = Parser->Run(/*NoInitialTextSection=*/true);
187 
188   return Res;
189 }
190 
191 int main(int Argc, char **Argv) {
192   InitLLVM X(Argc, Argv);
193   StringRef ProgName = sys::path::filename(Argv[0]);
194 
195   // Initialize targets and assembly printers/parsers.
196   llvm::InitializeAllTargetInfos();
197   llvm::InitializeAllTargetMCs();
198   llvm::InitializeAllAsmParsers();
199   llvm::InitializeAllDisassemblers();
200 
201   MLOptTable T;
202   unsigned MissingArgIndex, MissingArgCount;
203   ArrayRef<const char *> ArgsArr = makeArrayRef(Argv + 1, Argc - 1);
204   opt::InputArgList InputArgs =
205       T.ParseArgs(ArgsArr, MissingArgIndex, MissingArgCount);
206 
207   std::string InputFilename;
208   for (auto *Arg : InputArgs.filtered(OPT_INPUT)) {
209     std::string ArgString = Arg->getAsString(InputArgs);
210     if (ArgString == "-" || StringRef(ArgString).endswith(".asm")) {
211       if (!InputFilename.empty()) {
212         WithColor::warning(errs(), ProgName)
213             << "does not support multiple assembly files in one command; "
214             << "ignoring '" << InputFilename << "'\n";
215       }
216       InputFilename = ArgString;
217     } else {
218       std::string Diag;
219       raw_string_ostream OS(Diag);
220       OS << "invalid option '" << ArgString << "'";
221 
222       std::string Nearest;
223       if (T.findNearest(ArgString, Nearest) < 2)
224         OS << ", did you mean '" << Nearest << "'?";
225 
226       WithColor::error(errs(), ProgName) << OS.str() << '\n';
227       exit(1);
228     }
229   }
230   for (auto *Arg : InputArgs.filtered(OPT_assembly_file)) {
231     if (!InputFilename.empty()) {
232       WithColor::warning(errs(), ProgName)
233           << "does not support multiple assembly files in one command; "
234           << "ignoring '" << InputFilename << "'\n";
235     }
236     InputFilename = Arg->getAsString(InputArgs);
237   }
238 
239   for (auto *Arg : InputArgs.filtered(OPT_unsupported_Group)) {
240     WithColor::warning(errs(), ProgName)
241         << "ignoring unsupported '" << Arg->getOption().getName()
242         << "' option\n";
243   }
244 
245   if (InputArgs.hasArg(OPT_help)) {
246     std::string Usage = llvm::formatv("{0} [ /options ] file", ProgName).str();
247     T.printHelp(outs(), Usage.c_str(), "LLVM MASM Assembler",
248                 /*ShowHidden=*/false);
249     return 0;
250   } else if (InputFilename.empty()) {
251     outs() << "USAGE: " << ProgName << " [ /options ] file\n"
252            << "Run \"" << ProgName << " /?\" or \"" << ProgName
253            << " /help\" for more info.\n";
254     return 0;
255   }
256 
257   MCTargetOptions MCOptions;
258   MCOptions.AssemblyLanguage = "masm";
259   MCOptions.MCFatalWarnings = InputArgs.hasArg(OPT_fatal_warnings);
260 
261   Triple TheTriple = GetTriple(ProgName, InputArgs);
262   std::string Error;
263   const Target *TheTarget = TargetRegistry::lookupTarget("", TheTriple, Error);
264   if (!TheTarget) {
265     WithColor::error(errs(), ProgName) << Error;
266     return 1;
267   }
268   const std::string &TripleName = TheTriple.getTriple();
269 
270   bool SafeSEH = InputArgs.hasArg(OPT_safeseh);
271   if (SafeSEH && !(TheTriple.isArch32Bit() && TheTriple.isX86())) {
272     WithColor::warning()
273         << "/safeseh applies only to 32-bit X86 platforms; ignoring.\n";
274     SafeSEH = false;
275   }
276 
277   ErrorOr<std::unique_ptr<MemoryBuffer>> BufferPtr =
278       MemoryBuffer::getFileOrSTDIN(InputFilename);
279   if (std::error_code EC = BufferPtr.getError()) {
280     WithColor::error(errs(), ProgName)
281         << InputFilename << ": " << EC.message() << '\n';
282     return 1;
283   }
284 
285   SourceMgr SrcMgr;
286 
287   // Tell SrcMgr about this buffer, which is what the parser will pick up.
288   SrcMgr.AddNewSourceBuffer(std::move(*BufferPtr), SMLoc());
289 
290   // Record the location of the include directories so that the lexer can find
291   // included files later.
292   std::vector<std::string> IncludeDirs =
293       InputArgs.getAllArgValues(OPT_include_path);
294   if (!InputArgs.hasArg(OPT_ignore_include_envvar)) {
295     if (llvm::Optional<std::string> IncludeEnvVar =
296             llvm::sys::Process::GetEnv("INCLUDE")) {
297       SmallVector<StringRef, 8> Dirs;
298       StringRef(*IncludeEnvVar)
299           .split(Dirs, ";", /*MaxSplit=*/-1, /*KeepEmpty=*/false);
300       IncludeDirs.reserve(IncludeDirs.size() + Dirs.size());
301       for (StringRef Dir : Dirs)
302         IncludeDirs.push_back(Dir.str());
303     }
304   }
305   SrcMgr.setIncludeDirs(IncludeDirs);
306 
307   std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
308   assert(MRI && "Unable to create target register info!");
309 
310   std::unique_ptr<MCAsmInfo> MAI(
311       TheTarget->createMCAsmInfo(*MRI, TripleName, MCOptions));
312   assert(MAI && "Unable to create target asm info!");
313 
314   MAI->setPreserveAsmComments(InputArgs.hasArg(OPT_preserve_comments));
315 
316   std::unique_ptr<MCSubtargetInfo> STI(TheTarget->createMCSubtargetInfo(
317       TripleName, /*CPU=*/"", /*Features=*/""));
318   assert(STI && "Unable to create subtarget info!");
319 
320   // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
321   // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
322   MCContext Ctx(TheTriple, MAI.get(), MRI.get(), STI.get(), &SrcMgr);
323   std::unique_ptr<MCObjectFileInfo> MOFI(TheTarget->createMCObjectFileInfo(
324       Ctx, /*PIC=*/false, /*LargeCodeModel=*/true));
325   Ctx.setObjectFileInfo(MOFI.get());
326 
327   if (InputArgs.hasArg(OPT_save_temp_labels))
328     Ctx.setAllowTemporaryLabels(false);
329 
330   // Set compilation information.
331   SmallString<128> CWD;
332   if (!sys::fs::current_path(CWD))
333     Ctx.setCompilationDir(CWD);
334   Ctx.setMainFileName(InputFilename);
335 
336   StringRef FileType = InputArgs.getLastArgValue(OPT_filetype, "obj");
337   SmallString<255> DefaultOutputFilename;
338   if (InputArgs.hasArg(OPT_as_lex)) {
339     DefaultOutputFilename = "-";
340   } else {
341     DefaultOutputFilename = InputFilename;
342     sys::path::replace_extension(DefaultOutputFilename, FileType);
343   }
344   const StringRef OutputFilename =
345       InputArgs.getLastArgValue(OPT_output_file, DefaultOutputFilename);
346   std::unique_ptr<ToolOutputFile> Out = GetOutputStream(OutputFilename);
347   if (!Out)
348     return 1;
349 
350   std::unique_ptr<buffer_ostream> BOS;
351   raw_pwrite_stream *OS = &Out->os();
352   std::unique_ptr<MCStreamer> Str;
353 
354   std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
355   assert(MCII && "Unable to create instruction info!");
356 
357   MCInstPrinter *IP = nullptr;
358   if (FileType == "s") {
359     const bool OutputATTAsm = InputArgs.hasArg(OPT_output_att_asm);
360     const unsigned OutputAsmVariant = OutputATTAsm ? 0U   // ATT dialect
361                                                    : 1U;  // Intel dialect
362     IP = TheTarget->createMCInstPrinter(TheTriple, OutputAsmVariant, *MAI,
363                                         *MCII, *MRI);
364 
365     if (!IP) {
366       WithColor::error()
367           << "unable to create instruction printer for target triple '"
368           << TheTriple.normalize() << "' with "
369           << (OutputATTAsm ? "ATT" : "Intel") << " assembly variant.\n";
370       return 1;
371     }
372 
373     // Set the display preference for hex vs. decimal immediates.
374     IP->setPrintImmHex(InputArgs.hasArg(OPT_print_imm_hex));
375 
376     // Set up the AsmStreamer.
377     std::unique_ptr<MCCodeEmitter> CE;
378     if (InputArgs.hasArg(OPT_show_encoding))
379       CE.reset(TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx));
380 
381     std::unique_ptr<MCAsmBackend> MAB(
382         TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions));
383     auto FOut = std::make_unique<formatted_raw_ostream>(*OS);
384     Str.reset(TheTarget->createAsmStreamer(
385         Ctx, std::move(FOut), /*asmverbose*/ true,
386         /*useDwarfDirectory*/ true, IP, std::move(CE), std::move(MAB),
387         InputArgs.hasArg(OPT_show_inst)));
388 
389   } else if (FileType == "null") {
390     Str.reset(TheTarget->createNullStreamer(Ctx));
391   } else if (FileType == "obj") {
392     if (!Out->os().supportsSeeking()) {
393       BOS = std::make_unique<buffer_ostream>(Out->os());
394       OS = BOS.get();
395     }
396 
397     MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx);
398     MCAsmBackend *MAB = TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions);
399     Str.reset(TheTarget->createMCObjectStreamer(
400         TheTriple, Ctx, std::unique_ptr<MCAsmBackend>(MAB),
401         MAB->createObjectWriter(*OS), std::unique_ptr<MCCodeEmitter>(CE), *STI,
402         MCOptions.MCRelaxAll, MCOptions.MCIncrementalLinkerCompatible,
403         /*DWARFMustBeAtTheEnd*/ false));
404   } else {
405     llvm_unreachable("Invalid file type!");
406   }
407 
408   if (TheTriple.isOSBinFormatCOFF()) {
409     // Emit an absolute @feat.00 symbol. This is a features bitfield read by
410     // link.exe.
411     int64_t Feat00Flags = 0x2;
412     if (SafeSEH) {
413       // According to the PE-COFF spec, the LSB of this value marks the object
414       // for "registered SEH".  This means that all SEH handler entry points
415       // must be registered in .sxdata.  Use of any unregistered handlers will
416       // cause the process to terminate immediately.
417       Feat00Flags |= 0x1;
418     }
419     MCSymbol *Feat00Sym = Ctx.getOrCreateSymbol("@feat.00");
420     Feat00Sym->setRedefinable(true);
421     Str->emitSymbolAttribute(Feat00Sym, MCSA_Global);
422     Str->emitAssignment(Feat00Sym, MCConstantExpr::create(Feat00Flags, Ctx));
423   }
424 
425   // Use Assembler information for parsing.
426   Str->setUseAssemblerInfoForParsing(true);
427 
428   int Res = 1;
429   if (InputArgs.hasArg(OPT_as_lex)) {
430     // -as-lex; Lex only, and output a stream of tokens
431     Res = AsLexInput(SrcMgr, *MAI, Out->os());
432   } else {
433     Res = AssembleInput(ProgName, TheTarget, SrcMgr, Ctx, *Str, *MAI, *STI,
434                         *MCII, MCOptions, InputArgs);
435   }
436 
437   // Keep output if no errors.
438   if (Res == 0)
439     Out->keep();
440   return Res;
441 }
442