1 //===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
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 // This is the llc code generator driver. It provides a convenient
10 // command-line interface for generating native assembly-language code
11 // or C code, given LLVM bitcode.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/ADT/STLExtras.h"
16 #include "llvm/ADT/Triple.h"
17 #include "llvm/Analysis/TargetLibraryInfo.h"
18 #include "llvm/CodeGen/CommandFlags.h"
19 #include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
20 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
21 #include "llvm/CodeGen/MIRParser/MIRParser.h"
22 #include "llvm/CodeGen/MachineFunctionPass.h"
23 #include "llvm/CodeGen/MachineModuleInfo.h"
24 #include "llvm/CodeGen/TargetPassConfig.h"
25 #include "llvm/CodeGen/TargetSubtargetInfo.h"
26 #include "llvm/IR/AutoUpgrade.h"
27 #include "llvm/IR/DataLayout.h"
28 #include "llvm/IR/DiagnosticInfo.h"
29 #include "llvm/IR/DiagnosticPrinter.h"
30 #include "llvm/IR/IRPrintingPasses.h"
31 #include "llvm/IR/LLVMContext.h"
32 #include "llvm/IR/LLVMRemarkStreamer.h"
33 #include "llvm/IR/LegacyPassManager.h"
34 #include "llvm/IR/Module.h"
35 #include "llvm/IR/Verifier.h"
36 #include "llvm/IRReader/IRReader.h"
37 #include "llvm/InitializePasses.h"
38 #include "llvm/MC/SubtargetFeature.h"
39 #include "llvm/Pass.h"
40 #include "llvm/Remarks/HotnessThresholdParser.h"
41 #include "llvm/Support/CommandLine.h"
42 #include "llvm/Support/Debug.h"
43 #include "llvm/Support/FileSystem.h"
44 #include "llvm/Support/FormattedStream.h"
45 #include "llvm/Support/Host.h"
46 #include "llvm/Support/InitLLVM.h"
47 #include "llvm/Support/ManagedStatic.h"
48 #include "llvm/Support/PluginLoader.h"
49 #include "llvm/Support/SourceMgr.h"
50 #include "llvm/Support/TargetRegistry.h"
51 #include "llvm/Support/TargetSelect.h"
52 #include "llvm/Support/ToolOutputFile.h"
53 #include "llvm/Support/WithColor.h"
54 #include "llvm/Target/TargetLoweringObjectFile.h"
55 #include "llvm/Target/TargetMachine.h"
56 #include "llvm/Transforms/Utils/Cloning.h"
57 #include <memory>
58 using namespace llvm;
59
60 static codegen::RegisterCodeGenFlags CGF;
61
62 // General options for llc. Other pass-specific options are specified
63 // within the corresponding llc passes, and target-specific options
64 // and back-end code generation options are specified with the target machine.
65 //
66 static cl::opt<std::string>
67 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
68
69 static cl::opt<std::string>
70 InputLanguage("x", cl::desc("Input language ('ir' or 'mir')"));
71
72 static cl::opt<std::string>
73 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
74
75 static cl::opt<std::string>
76 SplitDwarfOutputFile("split-dwarf-output",
77 cl::desc(".dwo output filename"),
78 cl::value_desc("filename"));
79
80 static cl::opt<unsigned>
81 TimeCompilations("time-compilations", cl::Hidden, cl::init(1u),
82 cl::value_desc("N"),
83 cl::desc("Repeat compilation N times for timing"));
84
85 static cl::opt<std::string>
86 BinutilsVersion("binutils-version", cl::Hidden,
87 cl::desc("Produced object files can use all ELF features "
88 "supported by this binutils version and newer."
89 "If -no-integrated-as is specified, the generated "
90 "assembly will consider GNU as support."
91 "'none' means that all ELF features can be used, "
92 "regardless of binutils support"));
93
94 static cl::opt<bool>
95 NoIntegratedAssembler("no-integrated-as", cl::Hidden,
96 cl::desc("Disable integrated assembler"));
97
98 static cl::opt<bool>
99 PreserveComments("preserve-as-comments", cl::Hidden,
100 cl::desc("Preserve Comments in outputted assembly"),
101 cl::init(true));
102
103 // Determine optimization level.
104 static cl::opt<char>
105 OptLevel("O",
106 cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
107 "(default = '-O2')"),
108 cl::Prefix,
109 cl::ZeroOrMore,
110 cl::init(' '));
111
112 static cl::opt<std::string>
113 TargetTriple("mtriple", cl::desc("Override target triple for module"));
114
115 static cl::opt<std::string> SplitDwarfFile(
116 "split-dwarf-file",
117 cl::desc(
118 "Specify the name of the .dwo file to encode in the DWARF output"));
119
120 static cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
121 cl::desc("Do not verify input module"));
122
123 static cl::opt<bool> DisableSimplifyLibCalls("disable-simplify-libcalls",
124 cl::desc("Disable simplify-libcalls"));
125
126 static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
127 cl::desc("Show encoding in .s output"));
128
129 static cl::opt<bool>
130 DwarfDirectory("dwarf-directory", cl::Hidden,
131 cl::desc("Use .file directives with an explicit directory"),
132 cl::init(true));
133
134 static cl::opt<bool> AsmVerbose("asm-verbose",
135 cl::desc("Add comments to directives."),
136 cl::init(true));
137
138 static cl::opt<bool>
139 CompileTwice("compile-twice", cl::Hidden,
140 cl::desc("Run everything twice, re-using the same pass "
141 "manager and verify the result is the same."),
142 cl::init(false));
143
144 static cl::opt<bool> DiscardValueNames(
145 "discard-value-names",
146 cl::desc("Discard names from Value (other than GlobalValue)."),
147 cl::init(false), cl::Hidden);
148
149 static cl::list<std::string> IncludeDirs("I", cl::desc("include search path"));
150
151 static cl::opt<bool> RemarksWithHotness(
152 "pass-remarks-with-hotness",
153 cl::desc("With PGO, include profile count in optimization remarks"),
154 cl::Hidden);
155
156 static cl::opt<Optional<uint64_t>, false, remarks::HotnessThresholdParser>
157 RemarksHotnessThreshold(
158 "pass-remarks-hotness-threshold",
159 cl::desc("Minimum profile count required for "
160 "an optimization remark to be output. "
161 "Use 'auto' to apply the threshold from profile summary."),
162 cl::value_desc("N or 'auto'"), cl::init(0), cl::Hidden);
163
164 static cl::opt<std::string>
165 RemarksFilename("pass-remarks-output",
166 cl::desc("Output filename for pass remarks"),
167 cl::value_desc("filename"));
168
169 static cl::opt<std::string>
170 RemarksPasses("pass-remarks-filter",
171 cl::desc("Only record optimization remarks from passes whose "
172 "names match the given regular expression"),
173 cl::value_desc("regex"));
174
175 static cl::opt<std::string> RemarksFormat(
176 "pass-remarks-format",
177 cl::desc("The format used for serializing remarks (default: YAML)"),
178 cl::value_desc("format"), cl::init("yaml"));
179
180 namespace {
181 static ManagedStatic<std::vector<std::string>> RunPassNames;
182
183 struct RunPassOption {
operator =__anone98c7a670111::RunPassOption184 void operator=(const std::string &Val) const {
185 if (Val.empty())
186 return;
187 SmallVector<StringRef, 8> PassNames;
188 StringRef(Val).split(PassNames, ',', -1, false);
189 for (auto PassName : PassNames)
190 RunPassNames->push_back(std::string(PassName));
191 }
192 };
193 }
194
195 static RunPassOption RunPassOpt;
196
197 static cl::opt<RunPassOption, true, cl::parser<std::string>> RunPass(
198 "run-pass",
199 cl::desc("Run compiler only for specified passes (comma separated list)"),
200 cl::value_desc("pass-name"), cl::ZeroOrMore, cl::location(RunPassOpt));
201
202 static int compileModule(char **, LLVMContext &);
203
reportError(Twine Msg,StringRef Filename="")204 LLVM_ATTRIBUTE_NORETURN static void reportError(Twine Msg,
205 StringRef Filename = "") {
206 SmallString<256> Prefix;
207 if (!Filename.empty()) {
208 if (Filename == "-")
209 Filename = "<stdin>";
210 ("'" + Twine(Filename) + "': ").toStringRef(Prefix);
211 }
212 WithColor::error(errs(), "llc") << Prefix << Msg << "\n";
213 exit(1);
214 }
215
reportError(Error Err,StringRef Filename)216 LLVM_ATTRIBUTE_NORETURN static void reportError(Error Err, StringRef Filename) {
217 assert(Err);
218 handleAllErrors(createFileError(Filename, std::move(Err)),
219 [&](const ErrorInfoBase &EI) { reportError(EI.message()); });
220 llvm_unreachable("reportError() should not return");
221 }
222
GetOutputStream(const char * TargetName,Triple::OSType OS,const char * ProgName)223 static std::unique_ptr<ToolOutputFile> GetOutputStream(const char *TargetName,
224 Triple::OSType OS,
225 const char *ProgName) {
226 // If we don't yet have an output filename, make one.
227 if (OutputFilename.empty()) {
228 if (InputFilename == "-")
229 OutputFilename = "-";
230 else {
231 // If InputFilename ends in .bc or .ll, remove it.
232 StringRef IFN = InputFilename;
233 if (IFN.endswith(".bc") || IFN.endswith(".ll"))
234 OutputFilename = std::string(IFN.drop_back(3));
235 else if (IFN.endswith(".mir"))
236 OutputFilename = std::string(IFN.drop_back(4));
237 else
238 OutputFilename = std::string(IFN);
239
240 switch (codegen::getFileType()) {
241 case CGFT_AssemblyFile:
242 if (TargetName[0] == 'c') {
243 if (TargetName[1] == 0)
244 OutputFilename += ".cbe.c";
245 else if (TargetName[1] == 'p' && TargetName[2] == 'p')
246 OutputFilename += ".cpp";
247 else
248 OutputFilename += ".s";
249 } else
250 OutputFilename += ".s";
251 break;
252 case CGFT_ObjectFile:
253 if (OS == Triple::Win32)
254 OutputFilename += ".obj";
255 else
256 OutputFilename += ".o";
257 break;
258 case CGFT_Null:
259 OutputFilename = "-";
260 break;
261 }
262 }
263 }
264
265 // Decide if we need "binary" output.
266 bool Binary = false;
267 switch (codegen::getFileType()) {
268 case CGFT_AssemblyFile:
269 break;
270 case CGFT_ObjectFile:
271 case CGFT_Null:
272 Binary = true;
273 break;
274 }
275
276 // Open the file.
277 std::error_code EC;
278 sys::fs::OpenFlags OpenFlags = sys::fs::OF_None;
279 if (!Binary)
280 OpenFlags |= sys::fs::OF_TextWithCRLF;
281 auto FDOut = std::make_unique<ToolOutputFile>(OutputFilename, EC, OpenFlags);
282 if (EC) {
283 reportError(EC.message());
284 return nullptr;
285 }
286
287 return FDOut;
288 }
289
290 struct LLCDiagnosticHandler : public DiagnosticHandler {
291 bool *HasError;
LLCDiagnosticHandlerLLCDiagnosticHandler292 LLCDiagnosticHandler(bool *HasErrorPtr) : HasError(HasErrorPtr) {}
handleDiagnosticsLLCDiagnosticHandler293 bool handleDiagnostics(const DiagnosticInfo &DI) override {
294 if (DI.getKind() == llvm::DK_SrcMgr) {
295 const auto &DISM = cast<DiagnosticInfoSrcMgr>(DI);
296 const SMDiagnostic &SMD = DISM.getSMDiag();
297
298 if (SMD.getKind() == SourceMgr::DK_Error)
299 *HasError = true;
300
301 SMD.print(nullptr, errs());
302
303 // For testing purposes, we print the LocCookie here.
304 if (DISM.isInlineAsmDiag() && DISM.getLocCookie())
305 WithColor::note() << "!srcloc = " << DISM.getLocCookie() << "\n";
306
307 return true;
308 }
309
310 if (DI.getSeverity() == DS_Error)
311 *HasError = true;
312
313 if (auto *Remark = dyn_cast<DiagnosticInfoOptimizationBase>(&DI))
314 if (!Remark->isEnabled())
315 return true;
316
317 DiagnosticPrinterRawOStream DP(errs());
318 errs() << LLVMContext::getDiagnosticMessagePrefix(DI.getSeverity()) << ": ";
319 DI.print(DP);
320 errs() << "\n";
321 return true;
322 }
323 };
324
325 // main - Entry point for the llc compiler.
326 //
main(int argc,char ** argv)327 int main(int argc, char **argv) {
328 InitLLVM X(argc, argv);
329
330 // Enable debug stream buffering.
331 EnableDebugBuffering = true;
332
333 LLVMContext Context;
334
335 // Initialize targets first, so that --version shows registered targets.
336 InitializeAllTargets();
337 InitializeAllTargetMCs();
338 InitializeAllAsmPrinters();
339 InitializeAllAsmParsers();
340
341 // Initialize codegen and IR passes used by llc so that the -print-after,
342 // -print-before, and -stop-after options work.
343 PassRegistry *Registry = PassRegistry::getPassRegistry();
344 initializeCore(*Registry);
345 initializeCodeGen(*Registry);
346 initializeLoopStrengthReducePass(*Registry);
347 initializeLowerIntrinsicsPass(*Registry);
348 initializeEntryExitInstrumenterPass(*Registry);
349 initializePostInlineEntryExitInstrumenterPass(*Registry);
350 initializeUnreachableBlockElimLegacyPassPass(*Registry);
351 initializeConstantHoistingLegacyPassPass(*Registry);
352 initializeScalarOpts(*Registry);
353 initializeVectorization(*Registry);
354 initializeScalarizeMaskedMemIntrinLegacyPassPass(*Registry);
355 initializeExpandReductionsPass(*Registry);
356 initializeExpandVectorPredicationPass(*Registry);
357 initializeHardwareLoopsPass(*Registry);
358 initializeTransformUtils(*Registry);
359 initializeReplaceWithVeclibLegacyPass(*Registry);
360
361 // Initialize debugging passes.
362 initializeScavengerTestPass(*Registry);
363
364 // Register the target printer for --version.
365 cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
366
367 cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
368
369 Context.setDiscardValueNames(DiscardValueNames);
370
371 // Set a diagnostic handler that doesn't exit on the first error
372 bool HasError = false;
373 Context.setDiagnosticHandler(
374 std::make_unique<LLCDiagnosticHandler>(&HasError));
375
376 Expected<std::unique_ptr<ToolOutputFile>> RemarksFileOrErr =
377 setupLLVMOptimizationRemarks(Context, RemarksFilename, RemarksPasses,
378 RemarksFormat, RemarksWithHotness,
379 RemarksHotnessThreshold);
380 if (Error E = RemarksFileOrErr.takeError())
381 reportError(std::move(E), RemarksFilename);
382 std::unique_ptr<ToolOutputFile> RemarksFile = std::move(*RemarksFileOrErr);
383
384 if (InputLanguage != "" && InputLanguage != "ir" && InputLanguage != "mir")
385 reportError("input language must be '', 'IR' or 'MIR'");
386
387 // Compile the module TimeCompilations times to give better compile time
388 // metrics.
389 for (unsigned I = TimeCompilations; I; --I)
390 if (int RetVal = compileModule(argv, Context))
391 return RetVal;
392
393 if (RemarksFile)
394 RemarksFile->keep();
395 return 0;
396 }
397
addPass(PassManagerBase & PM,const char * argv0,StringRef PassName,TargetPassConfig & TPC)398 static bool addPass(PassManagerBase &PM, const char *argv0,
399 StringRef PassName, TargetPassConfig &TPC) {
400 if (PassName == "none")
401 return false;
402
403 const PassRegistry *PR = PassRegistry::getPassRegistry();
404 const PassInfo *PI = PR->getPassInfo(PassName);
405 if (!PI) {
406 WithColor::error(errs(), argv0)
407 << "run-pass " << PassName << " is not registered.\n";
408 return true;
409 }
410
411 Pass *P;
412 if (PI->getNormalCtor())
413 P = PI->getNormalCtor()();
414 else {
415 WithColor::error(errs(), argv0)
416 << "cannot create pass: " << PI->getPassName() << "\n";
417 return true;
418 }
419 std::string Banner = std::string("After ") + std::string(P->getPassName());
420 TPC.addMachinePrePasses();
421 PM.add(P);
422 TPC.addMachinePostPasses(Banner);
423
424 return false;
425 }
426
compileModule(char ** argv,LLVMContext & Context)427 static int compileModule(char **argv, LLVMContext &Context) {
428 // Load the module to be compiled...
429 SMDiagnostic Err;
430 std::unique_ptr<Module> M;
431 std::unique_ptr<MIRParser> MIR;
432 Triple TheTriple;
433 std::string CPUStr = codegen::getCPUStr(),
434 FeaturesStr = codegen::getFeaturesStr();
435
436 // Set attributes on functions as loaded from MIR from command line arguments.
437 auto setMIRFunctionAttributes = [&CPUStr, &FeaturesStr](Function &F) {
438 codegen::setFunctionAttributes(CPUStr, FeaturesStr, F);
439 };
440
441 auto MAttrs = codegen::getMAttrs();
442 bool SkipModule = codegen::getMCPU() == "help" ||
443 (!MAttrs.empty() && MAttrs.front() == "help");
444
445 CodeGenOpt::Level OLvl = CodeGenOpt::Default;
446 switch (OptLevel) {
447 default:
448 WithColor::error(errs(), argv[0]) << "invalid optimization level.\n";
449 return 1;
450 case ' ': break;
451 case '0': OLvl = CodeGenOpt::None; break;
452 case '1': OLvl = CodeGenOpt::Less; break;
453 case '2': OLvl = CodeGenOpt::Default; break;
454 case '3': OLvl = CodeGenOpt::Aggressive; break;
455 }
456
457 // Parse 'none' or '$major.$minor'. Disallow -binutils-version=0 because we
458 // use that to indicate the MC default.
459 if (!BinutilsVersion.empty() && BinutilsVersion != "none") {
460 StringRef V = BinutilsVersion.getValue();
461 unsigned Num;
462 if (V.consumeInteger(10, Num) || Num == 0 ||
463 !(V.empty() ||
464 (V.consume_front(".") && !V.consumeInteger(10, Num) && V.empty()))) {
465 WithColor::error(errs(), argv[0])
466 << "invalid -binutils-version, accepting 'none' or major.minor\n";
467 return 1;
468 }
469 }
470 TargetOptions Options;
471 auto InitializeOptions = [&](const Triple &TheTriple) {
472 Options = codegen::InitTargetOptionsFromCodeGenFlags(TheTriple);
473 Options.BinutilsVersion =
474 TargetMachine::parseBinutilsVersion(BinutilsVersion);
475 Options.DisableIntegratedAS = NoIntegratedAssembler;
476 Options.MCOptions.ShowMCEncoding = ShowMCEncoding;
477 Options.MCOptions.MCUseDwarfDirectory = DwarfDirectory;
478 Options.MCOptions.AsmVerbose = AsmVerbose;
479 Options.MCOptions.PreserveAsmComments = PreserveComments;
480 Options.MCOptions.IASSearchPaths = IncludeDirs;
481 Options.MCOptions.SplitDwarfFile = SplitDwarfFile;
482 };
483
484 Optional<Reloc::Model> RM = codegen::getExplicitRelocModel();
485
486 const Target *TheTarget = nullptr;
487 std::unique_ptr<TargetMachine> Target;
488
489 // If user just wants to list available options, skip module loading
490 if (!SkipModule) {
491 auto SetDataLayout =
492 [&](StringRef DataLayoutTargetTriple) -> Optional<std::string> {
493 // If we are supposed to override the target triple, do so now.
494 std::string IRTargetTriple = DataLayoutTargetTriple.str();
495 if (!TargetTriple.empty())
496 IRTargetTriple = Triple::normalize(TargetTriple);
497 TheTriple = Triple(IRTargetTriple);
498 if (TheTriple.getTriple().empty())
499 TheTriple.setTriple(sys::getDefaultTargetTriple());
500
501 std::string Error;
502 TheTarget =
503 TargetRegistry::lookupTarget(codegen::getMArch(), TheTriple, Error);
504 if (!TheTarget) {
505 WithColor::error(errs(), argv[0]) << Error;
506 exit(1);
507 }
508
509 // On AIX, setting the relocation model to anything other than PIC is
510 // considered a user error.
511 if (TheTriple.isOSAIX() && RM.hasValue() && *RM != Reloc::PIC_)
512 reportError("invalid relocation model, AIX only supports PIC",
513 InputFilename);
514
515 InitializeOptions(TheTriple);
516 Target = std::unique_ptr<TargetMachine>(TheTarget->createTargetMachine(
517 TheTriple.getTriple(), CPUStr, FeaturesStr, Options, RM,
518 codegen::getExplicitCodeModel(), OLvl));
519 assert(Target && "Could not allocate target machine!");
520
521 return Target->createDataLayout().getStringRepresentation();
522 };
523 if (InputLanguage == "mir" ||
524 (InputLanguage == "" && StringRef(InputFilename).endswith(".mir"))) {
525 MIR = createMIRParserFromFile(InputFilename, Err, Context,
526 setMIRFunctionAttributes);
527 if (MIR)
528 M = MIR->parseIRModule(SetDataLayout);
529 } else {
530 M = parseIRFile(InputFilename, Err, Context, SetDataLayout);
531 }
532 if (!M) {
533 Err.print(argv[0], WithColor::error(errs(), argv[0]));
534 return 1;
535 }
536 if (!TargetTriple.empty())
537 M->setTargetTriple(Triple::normalize(TargetTriple));
538 } else {
539 TheTriple = Triple(Triple::normalize(TargetTriple));
540 if (TheTriple.getTriple().empty())
541 TheTriple.setTriple(sys::getDefaultTargetTriple());
542
543 // Get the target specific parser.
544 std::string Error;
545 TheTarget =
546 TargetRegistry::lookupTarget(codegen::getMArch(), TheTriple, Error);
547 if (!TheTarget) {
548 WithColor::error(errs(), argv[0]) << Error;
549 return 1;
550 }
551
552 // On AIX, setting the relocation model to anything other than PIC is
553 // considered a user error.
554 if (TheTriple.isOSAIX() && RM.hasValue() && *RM != Reloc::PIC_) {
555 WithColor::error(errs(), argv[0])
556 << "invalid relocation model, AIX only supports PIC.\n";
557 return 1;
558 }
559
560 InitializeOptions(TheTriple);
561 Target = std::unique_ptr<TargetMachine>(TheTarget->createTargetMachine(
562 TheTriple.getTriple(), CPUStr, FeaturesStr, Options, RM,
563 codegen::getExplicitCodeModel(), OLvl));
564 assert(Target && "Could not allocate target machine!");
565
566 // If we don't have a module then just exit now. We do this down
567 // here since the CPU/Feature help is underneath the target machine
568 // creation.
569 return 0;
570 }
571
572 assert(M && "Should have exited if we didn't have a module!");
573 if (codegen::getFloatABIForCalls() != FloatABI::Default)
574 Options.FloatABIType = codegen::getFloatABIForCalls();
575
576 // Figure out where we are going to send the output.
577 std::unique_ptr<ToolOutputFile> Out =
578 GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0]);
579 if (!Out) return 1;
580
581 std::unique_ptr<ToolOutputFile> DwoOut;
582 if (!SplitDwarfOutputFile.empty()) {
583 std::error_code EC;
584 DwoOut = std::make_unique<ToolOutputFile>(SplitDwarfOutputFile, EC,
585 sys::fs::OF_None);
586 if (EC)
587 reportError(EC.message(), SplitDwarfOutputFile);
588 }
589
590 // Build up all of the passes that we want to do to the module.
591 legacy::PassManager PM;
592
593 // Add an appropriate TargetLibraryInfo pass for the module's triple.
594 TargetLibraryInfoImpl TLII(Triple(M->getTargetTriple()));
595
596 // The -disable-simplify-libcalls flag actually disables all builtin optzns.
597 if (DisableSimplifyLibCalls)
598 TLII.disableAllFunctions();
599 PM.add(new TargetLibraryInfoWrapperPass(TLII));
600
601 // Verify module immediately to catch problems before doInitialization() is
602 // called on any passes.
603 if (!NoVerify && verifyModule(*M, &errs()))
604 reportError("input module cannot be verified", InputFilename);
605
606 // Override function attributes based on CPUStr, FeaturesStr, and command line
607 // flags.
608 codegen::setFunctionAttributes(CPUStr, FeaturesStr, *M);
609
610 if (mc::getExplicitRelaxAll() && codegen::getFileType() != CGFT_ObjectFile)
611 WithColor::warning(errs(), argv[0])
612 << ": warning: ignoring -mc-relax-all because filetype != obj";
613
614 {
615 raw_pwrite_stream *OS = &Out->os();
616
617 // Manually do the buffering rather than using buffer_ostream,
618 // so we can memcmp the contents in CompileTwice mode
619 SmallVector<char, 0> Buffer;
620 std::unique_ptr<raw_svector_ostream> BOS;
621 if ((codegen::getFileType() != CGFT_AssemblyFile &&
622 !Out->os().supportsSeeking()) ||
623 CompileTwice) {
624 BOS = std::make_unique<raw_svector_ostream>(Buffer);
625 OS = BOS.get();
626 }
627
628 const char *argv0 = argv[0];
629 LLVMTargetMachine &LLVMTM = static_cast<LLVMTargetMachine &>(*Target);
630 MachineModuleInfoWrapperPass *MMIWP =
631 new MachineModuleInfoWrapperPass(&LLVMTM);
632
633 // Construct a custom pass pipeline that starts after instruction
634 // selection.
635 if (!RunPassNames->empty()) {
636 if (!MIR) {
637 WithColor::warning(errs(), argv[0])
638 << "run-pass is for .mir file only.\n";
639 return 1;
640 }
641 TargetPassConfig &TPC = *LLVMTM.createPassConfig(PM);
642 if (TPC.hasLimitedCodeGenPipeline()) {
643 WithColor::warning(errs(), argv[0])
644 << "run-pass cannot be used with "
645 << TPC.getLimitedCodeGenPipelineReason(" and ") << ".\n";
646 return 1;
647 }
648
649 TPC.setDisableVerify(NoVerify);
650 PM.add(&TPC);
651 PM.add(MMIWP);
652 TPC.printAndVerify("");
653 for (const std::string &RunPassName : *RunPassNames) {
654 if (addPass(PM, argv0, RunPassName, TPC))
655 return 1;
656 }
657 TPC.setInitialized();
658 PM.add(createPrintMIRPass(*OS));
659 PM.add(createFreeMachineFunctionPass());
660 } else if (Target->addPassesToEmitFile(
661 PM, *OS, DwoOut ? &DwoOut->os() : nullptr,
662 codegen::getFileType(), NoVerify, MMIWP)) {
663 reportError("target does not support generation of this file type");
664 }
665
666 const_cast<TargetLoweringObjectFile *>(LLVMTM.getObjFileLowering())
667 ->Initialize(MMIWP->getMMI().getContext(), *Target);
668 if (MIR) {
669 assert(MMIWP && "Forgot to create MMIWP?");
670 if (MIR->parseMachineFunctions(*M, MMIWP->getMMI()))
671 return 1;
672 }
673
674 // Before executing passes, print the final values of the LLVM options.
675 cl::PrintOptionValues();
676
677 // If requested, run the pass manager over the same module again,
678 // to catch any bugs due to persistent state in the passes. Note that
679 // opt has the same functionality, so it may be worth abstracting this out
680 // in the future.
681 SmallVector<char, 0> CompileTwiceBuffer;
682 if (CompileTwice) {
683 std::unique_ptr<Module> M2(llvm::CloneModule(*M));
684 PM.run(*M2);
685 CompileTwiceBuffer = Buffer;
686 Buffer.clear();
687 }
688
689 PM.run(*M);
690
691 auto HasError =
692 ((const LLCDiagnosticHandler *)(Context.getDiagHandlerPtr()))->HasError;
693 if (*HasError)
694 return 1;
695
696 // Compare the two outputs and make sure they're the same
697 if (CompileTwice) {
698 if (Buffer.size() != CompileTwiceBuffer.size() ||
699 (memcmp(Buffer.data(), CompileTwiceBuffer.data(), Buffer.size()) !=
700 0)) {
701 errs()
702 << "Running the pass manager twice changed the output.\n"
703 "Writing the result of the second run to the specified output\n"
704 "To generate the one-run comparison binary, just run without\n"
705 "the compile-twice option\n";
706 Out->os() << Buffer;
707 Out->keep();
708 return 1;
709 }
710 }
711
712 if (BOS) {
713 Out->os() << Buffer;
714 }
715 }
716
717 // Declare success.
718 Out->keep();
719 if (DwoOut)
720 DwoOut->keep();
721
722 return 0;
723 }
724