1 //===--- BackendUtil.cpp - LLVM Backend Utilities -------------------------===//
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 #include "clang/CodeGen/BackendUtil.h"
11 #include "clang/Basic/Diagnostic.h"
12 #include "clang/Basic/LangOptions.h"
13 #include "clang/Basic/TargetOptions.h"
14 #include "clang/Frontend/CodeGenOptions.h"
15 #include "clang/Frontend/FrontendDiagnostic.h"
16 #include "llvm/Analysis/Verifier.h"
17 #include "llvm/Assembly/PrintModulePass.h"
18 #include "llvm/Bitcode/ReaderWriter.h"
19 #include "llvm/CodeGen/RegAllocRegistry.h"
20 #include "llvm/CodeGen/SchedulerRegistry.h"
21 #include "llvm/IR/DataLayout.h"
22 #include "llvm/IR/Module.h"
23 #include "llvm/MC/SubtargetFeature.h"
24 #include "llvm/PassManager.h"
25 #include "llvm/Support/CommandLine.h"
26 #include "llvm/Support/FormattedStream.h"
27 #include "llvm/Support/PrettyStackTrace.h"
28 #include "llvm/Support/TargetRegistry.h"
29 #include "llvm/Support/Timer.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include "llvm/Target/TargetLibraryInfo.h"
32 #include "llvm/Target/TargetMachine.h"
33 #include "llvm/Target/TargetOptions.h"
34 #include "llvm/Transforms/IPO.h"
35 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
36 #include "llvm/Transforms/Instrumentation.h"
37 #include "llvm/Transforms/ObjCARC.h"
38 #include "llvm/Transforms/Scalar.h"
39 using namespace clang;
40 using namespace llvm;
41
42 namespace {
43
44 class EmitAssemblyHelper {
45 DiagnosticsEngine &Diags;
46 const CodeGenOptions &CodeGenOpts;
47 const clang::TargetOptions &TargetOpts;
48 const LangOptions &LangOpts;
49 Module *TheModule;
50
51 Timer CodeGenerationTime;
52
53 mutable PassManager *CodeGenPasses;
54 mutable PassManager *PerModulePasses;
55 mutable FunctionPassManager *PerFunctionPasses;
56
57 private:
getCodeGenPasses(TargetMachine * TM) const58 PassManager *getCodeGenPasses(TargetMachine *TM) const {
59 if (!CodeGenPasses) {
60 CodeGenPasses = new PassManager();
61 CodeGenPasses->add(new DataLayout(TheModule));
62 if (TM)
63 TM->addAnalysisPasses(*CodeGenPasses);
64 }
65 return CodeGenPasses;
66 }
67
getPerModulePasses(TargetMachine * TM) const68 PassManager *getPerModulePasses(TargetMachine *TM) const {
69 if (!PerModulePasses) {
70 PerModulePasses = new PassManager();
71 PerModulePasses->add(new DataLayout(TheModule));
72 if (TM)
73 TM->addAnalysisPasses(*PerModulePasses);
74 }
75 return PerModulePasses;
76 }
77
getPerFunctionPasses(TargetMachine * TM) const78 FunctionPassManager *getPerFunctionPasses(TargetMachine *TM) const {
79 if (!PerFunctionPasses) {
80 PerFunctionPasses = new FunctionPassManager(TheModule);
81 PerFunctionPasses->add(new DataLayout(TheModule));
82 if (TM)
83 TM->addAnalysisPasses(*PerFunctionPasses);
84 }
85 return PerFunctionPasses;
86 }
87
88
89 void CreatePasses(TargetMachine *TM);
90
91 /// CreateTargetMachine - Generates the TargetMachine.
92 /// Returns Null if it is unable to create the target machine.
93 /// Some of our clang tests specify triples which are not built
94 /// into clang. This is okay because these tests check the generated
95 /// IR, and they require DataLayout which depends on the triple.
96 /// In this case, we allow this method to fail and not report an error.
97 /// When MustCreateTM is used, we print an error if we are unable to load
98 /// the requested target.
99 TargetMachine *CreateTargetMachine(bool MustCreateTM);
100
101 /// AddEmitPasses - Add passes necessary to emit assembly or LLVM IR.
102 ///
103 /// \return True on success.
104 bool AddEmitPasses(BackendAction Action, formatted_raw_ostream &OS,
105 TargetMachine *TM);
106
107 public:
EmitAssemblyHelper(DiagnosticsEngine & _Diags,const CodeGenOptions & CGOpts,const clang::TargetOptions & TOpts,const LangOptions & LOpts,Module * M)108 EmitAssemblyHelper(DiagnosticsEngine &_Diags,
109 const CodeGenOptions &CGOpts,
110 const clang::TargetOptions &TOpts,
111 const LangOptions &LOpts,
112 Module *M)
113 : Diags(_Diags), CodeGenOpts(CGOpts), TargetOpts(TOpts), LangOpts(LOpts),
114 TheModule(M), CodeGenerationTime("Code Generation Time"),
115 CodeGenPasses(0), PerModulePasses(0), PerFunctionPasses(0) {}
116
~EmitAssemblyHelper()117 ~EmitAssemblyHelper() {
118 delete CodeGenPasses;
119 delete PerModulePasses;
120 delete PerFunctionPasses;
121 }
122
123 void EmitAssembly(BackendAction Action, raw_ostream *OS);
124 };
125
126 // We need this wrapper to access LangOpts and CGOpts from extension functions
127 // that we add to the PassManagerBuilder.
128 class PassManagerBuilderWrapper : public PassManagerBuilder {
129 public:
PassManagerBuilderWrapper(const CodeGenOptions & CGOpts,const LangOptions & LangOpts)130 PassManagerBuilderWrapper(const CodeGenOptions &CGOpts,
131 const LangOptions &LangOpts)
132 : PassManagerBuilder(), CGOpts(CGOpts), LangOpts(LangOpts) {}
getCGOpts() const133 const CodeGenOptions &getCGOpts() const { return CGOpts; }
getLangOpts() const134 const LangOptions &getLangOpts() const { return LangOpts; }
135 private:
136 const CodeGenOptions &CGOpts;
137 const LangOptions &LangOpts;
138 };
139
140 }
141
addObjCARCAPElimPass(const PassManagerBuilder & Builder,PassManagerBase & PM)142 static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
143 if (Builder.OptLevel > 0)
144 PM.add(createObjCARCAPElimPass());
145 }
146
addObjCARCExpandPass(const PassManagerBuilder & Builder,PassManagerBase & PM)147 static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
148 if (Builder.OptLevel > 0)
149 PM.add(createObjCARCExpandPass());
150 }
151
addObjCARCOptPass(const PassManagerBuilder & Builder,PassManagerBase & PM)152 static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
153 if (Builder.OptLevel > 0)
154 PM.add(createObjCARCOptPass());
155 }
156
addBoundsCheckingPass(const PassManagerBuilder & Builder,PassManagerBase & PM)157 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
158 PassManagerBase &PM) {
159 PM.add(createBoundsCheckingPass());
160 }
161
addAddressSanitizerPasses(const PassManagerBuilder & Builder,PassManagerBase & PM)162 static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
163 PassManagerBase &PM) {
164 const PassManagerBuilderWrapper &BuilderWrapper =
165 static_cast<const PassManagerBuilderWrapper&>(Builder);
166 const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
167 const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
168 PM.add(createAddressSanitizerFunctionPass(
169 LangOpts.Sanitize.InitOrder,
170 LangOpts.Sanitize.UseAfterReturn,
171 LangOpts.Sanitize.UseAfterScope,
172 CGOpts.SanitizerBlacklistFile,
173 CGOpts.SanitizeAddressZeroBaseShadow));
174 PM.add(createAddressSanitizerModulePass(
175 LangOpts.Sanitize.InitOrder,
176 CGOpts.SanitizerBlacklistFile,
177 CGOpts.SanitizeAddressZeroBaseShadow));
178 }
179
addMemorySanitizerPass(const PassManagerBuilder & Builder,PassManagerBase & PM)180 static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
181 PassManagerBase &PM) {
182 const PassManagerBuilderWrapper &BuilderWrapper =
183 static_cast<const PassManagerBuilderWrapper&>(Builder);
184 const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
185 PM.add(createMemorySanitizerPass(CGOpts.SanitizeMemoryTrackOrigins,
186 CGOpts.SanitizerBlacklistFile));
187
188 // MemorySanitizer inserts complex instrumentation that mostly follows
189 // the logic of the original code, but operates on "shadow" values.
190 // It can benefit from re-running some general purpose optimization passes.
191 if (Builder.OptLevel > 0) {
192 PM.add(createEarlyCSEPass());
193 PM.add(createReassociatePass());
194 PM.add(createLICMPass());
195 PM.add(createGVNPass());
196 PM.add(createInstructionCombiningPass());
197 PM.add(createDeadStoreEliminationPass());
198 }
199 }
200
addThreadSanitizerPass(const PassManagerBuilder & Builder,PassManagerBase & PM)201 static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
202 PassManagerBase &PM) {
203 const PassManagerBuilderWrapper &BuilderWrapper =
204 static_cast<const PassManagerBuilderWrapper&>(Builder);
205 const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
206 PM.add(createThreadSanitizerPass(CGOpts.SanitizerBlacklistFile));
207 }
208
CreatePasses(TargetMachine * TM)209 void EmitAssemblyHelper::CreatePasses(TargetMachine *TM) {
210 unsigned OptLevel = CodeGenOpts.OptimizationLevel;
211 CodeGenOptions::InliningMethod Inlining = CodeGenOpts.getInlining();
212
213 // Handle disabling of LLVM optimization, where we want to preserve the
214 // internal module before any optimization.
215 if (CodeGenOpts.DisableLLVMOpts) {
216 OptLevel = 0;
217 Inlining = CodeGenOpts.NoInlining;
218 }
219
220 PassManagerBuilderWrapper PMBuilder(CodeGenOpts, LangOpts);
221 PMBuilder.OptLevel = OptLevel;
222 PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
223 PMBuilder.BBVectorize = CodeGenOpts.VectorizeBB;
224 PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
225 PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
226
227 PMBuilder.DisableUnitAtATime = !CodeGenOpts.UnitAtATime;
228 PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
229
230 // In ObjC ARC mode, add the main ARC optimization passes.
231 if (LangOpts.ObjCAutoRefCount) {
232 PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
233 addObjCARCExpandPass);
234 PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
235 addObjCARCAPElimPass);
236 PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
237 addObjCARCOptPass);
238 }
239
240 if (LangOpts.Sanitize.Bounds) {
241 PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
242 addBoundsCheckingPass);
243 PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
244 addBoundsCheckingPass);
245 }
246
247 if (LangOpts.Sanitize.Address) {
248 PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
249 addAddressSanitizerPasses);
250 PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
251 addAddressSanitizerPasses);
252 }
253
254 if (LangOpts.Sanitize.Memory) {
255 PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
256 addMemorySanitizerPass);
257 PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
258 addMemorySanitizerPass);
259 }
260
261 if (LangOpts.Sanitize.Thread) {
262 PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
263 addThreadSanitizerPass);
264 PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
265 addThreadSanitizerPass);
266 }
267
268 // Figure out TargetLibraryInfo.
269 Triple TargetTriple(TheModule->getTargetTriple());
270 PMBuilder.LibraryInfo = new TargetLibraryInfo(TargetTriple);
271 if (!CodeGenOpts.SimplifyLibCalls)
272 PMBuilder.LibraryInfo->disableAllFunctions();
273
274 switch (Inlining) {
275 case CodeGenOptions::NoInlining: break;
276 case CodeGenOptions::NormalInlining: {
277 // FIXME: Derive these constants in a principled fashion.
278 unsigned Threshold = 225;
279 if (CodeGenOpts.OptimizeSize == 1) // -Os
280 Threshold = 75;
281 else if (CodeGenOpts.OptimizeSize == 2) // -Oz
282 Threshold = 25;
283 else if (OptLevel > 2)
284 Threshold = 275;
285 PMBuilder.Inliner = createFunctionInliningPass(Threshold);
286 break;
287 }
288 case CodeGenOptions::OnlyAlwaysInlining:
289 // Respect always_inline.
290 if (OptLevel == 0)
291 // Do not insert lifetime intrinsics at -O0.
292 PMBuilder.Inliner = createAlwaysInlinerPass(false);
293 else
294 PMBuilder.Inliner = createAlwaysInlinerPass();
295 break;
296 }
297
298 // Set up the per-function pass manager.
299 FunctionPassManager *FPM = getPerFunctionPasses(TM);
300 if (CodeGenOpts.VerifyModule)
301 FPM->add(createVerifierPass());
302 PMBuilder.populateFunctionPassManager(*FPM);
303
304 // Set up the per-module pass manager.
305 PassManager *MPM = getPerModulePasses(TM);
306
307 if (!CodeGenOpts.DisableGCov &&
308 (CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)) {
309 // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
310 // LLVM's -default-gcov-version flag is set to something invalid.
311 GCOVOptions Options;
312 Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
313 Options.EmitData = CodeGenOpts.EmitGcovArcs;
314 memcpy(Options.Version, CodeGenOpts.CoverageVersion, 4);
315 Options.UseCfgChecksum = CodeGenOpts.CoverageExtraChecksum;
316 Options.NoRedZone = CodeGenOpts.DisableRedZone;
317 Options.FunctionNamesInData =
318 !CodeGenOpts.CoverageNoFunctionNamesInData;
319 MPM->add(createGCOVProfilerPass(Options));
320 if (CodeGenOpts.getDebugInfo() == CodeGenOptions::NoDebugInfo)
321 MPM->add(createStripSymbolsPass(true));
322 }
323
324 PMBuilder.populateModulePassManager(*MPM);
325 }
326
CreateTargetMachine(bool MustCreateTM)327 TargetMachine *EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
328 // Create the TargetMachine for generating code.
329 std::string Error;
330 std::string Triple = TheModule->getTargetTriple();
331 const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
332 if (!TheTarget) {
333 if (MustCreateTM)
334 Diags.Report(diag::err_fe_unable_to_create_target) << Error;
335 return 0;
336 }
337
338 // FIXME: Expose these capabilities via actual APIs!!!! Aside from just
339 // being gross, this is also totally broken if we ever care about
340 // concurrency.
341
342 TargetMachine::setAsmVerbosityDefault(CodeGenOpts.AsmVerbose);
343
344 TargetMachine::setFunctionSections(CodeGenOpts.FunctionSections);
345 TargetMachine::setDataSections (CodeGenOpts.DataSections);
346
347 // FIXME: Parse this earlier.
348 llvm::CodeModel::Model CM;
349 if (CodeGenOpts.CodeModel == "small") {
350 CM = llvm::CodeModel::Small;
351 } else if (CodeGenOpts.CodeModel == "kernel") {
352 CM = llvm::CodeModel::Kernel;
353 } else if (CodeGenOpts.CodeModel == "medium") {
354 CM = llvm::CodeModel::Medium;
355 } else if (CodeGenOpts.CodeModel == "large") {
356 CM = llvm::CodeModel::Large;
357 } else {
358 assert(CodeGenOpts.CodeModel.empty() && "Invalid code model!");
359 CM = llvm::CodeModel::Default;
360 }
361
362 SmallVector<const char *, 16> BackendArgs;
363 BackendArgs.push_back("clang"); // Fake program name.
364 if (!CodeGenOpts.DebugPass.empty()) {
365 BackendArgs.push_back("-debug-pass");
366 BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
367 }
368 if (!CodeGenOpts.LimitFloatPrecision.empty()) {
369 BackendArgs.push_back("-limit-float-precision");
370 BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
371 }
372 if (llvm::TimePassesIsEnabled)
373 BackendArgs.push_back("-time-passes");
374 for (unsigned i = 0, e = CodeGenOpts.BackendOptions.size(); i != e; ++i)
375 BackendArgs.push_back(CodeGenOpts.BackendOptions[i].c_str());
376 if (CodeGenOpts.NoGlobalMerge)
377 BackendArgs.push_back("-global-merge=false");
378 BackendArgs.push_back(0);
379 llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
380 BackendArgs.data());
381
382 std::string FeaturesStr;
383 if (TargetOpts.Features.size()) {
384 SubtargetFeatures Features;
385 for (std::vector<std::string>::const_iterator
386 it = TargetOpts.Features.begin(),
387 ie = TargetOpts.Features.end(); it != ie; ++it)
388 Features.AddFeature(*it);
389 FeaturesStr = Features.getString();
390 }
391
392 llvm::Reloc::Model RM = llvm::Reloc::Default;
393 if (CodeGenOpts.RelocationModel == "static") {
394 RM = llvm::Reloc::Static;
395 } else if (CodeGenOpts.RelocationModel == "pic") {
396 RM = llvm::Reloc::PIC_;
397 } else {
398 assert(CodeGenOpts.RelocationModel == "dynamic-no-pic" &&
399 "Invalid PIC model!");
400 RM = llvm::Reloc::DynamicNoPIC;
401 }
402
403 CodeGenOpt::Level OptLevel = CodeGenOpt::Default;
404 switch (CodeGenOpts.OptimizationLevel) {
405 default: break;
406 case 0: OptLevel = CodeGenOpt::None; break;
407 case 3: OptLevel = CodeGenOpt::Aggressive; break;
408 }
409
410 llvm::TargetOptions Options;
411
412 // Set frame pointer elimination mode.
413 if (!CodeGenOpts.DisableFPElim) {
414 Options.NoFramePointerElim = false;
415 } else if (CodeGenOpts.OmitLeafFramePointer) {
416 Options.NoFramePointerElim = false;
417 } else {
418 Options.NoFramePointerElim = true;
419 }
420
421 if (CodeGenOpts.UseInitArray)
422 Options.UseInitArray = true;
423
424 // Set float ABI type.
425 if (CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp")
426 Options.FloatABIType = llvm::FloatABI::Soft;
427 else if (CodeGenOpts.FloatABI == "hard")
428 Options.FloatABIType = llvm::FloatABI::Hard;
429 else {
430 assert(CodeGenOpts.FloatABI.empty() && "Invalid float abi!");
431 Options.FloatABIType = llvm::FloatABI::Default;
432 }
433
434 // Set FP fusion mode.
435 switch (CodeGenOpts.getFPContractMode()) {
436 case CodeGenOptions::FPC_Off:
437 Options.AllowFPOpFusion = llvm::FPOpFusion::Strict;
438 break;
439 case CodeGenOptions::FPC_On:
440 Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
441 break;
442 case CodeGenOptions::FPC_Fast:
443 Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
444 break;
445 }
446
447 Options.LessPreciseFPMADOption = CodeGenOpts.LessPreciseFPMAD;
448 Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath;
449 Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath;
450 Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
451 Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath;
452 Options.UseSoftFloat = CodeGenOpts.SoftFloat;
453 Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
454 Options.DisableTailCalls = CodeGenOpts.DisableTailCalls;
455 Options.TrapFuncName = CodeGenOpts.TrapFuncName;
456 Options.PositionIndependentExecutable = LangOpts.PIELevel != 0;
457 Options.EnableSegmentedStacks = CodeGenOpts.EnableSegmentedStacks;
458
459 TargetMachine *TM = TheTarget->createTargetMachine(Triple, TargetOpts.CPU,
460 FeaturesStr, Options,
461 RM, CM, OptLevel);
462
463 if (CodeGenOpts.RelaxAll)
464 TM->setMCRelaxAll(true);
465 if (CodeGenOpts.SaveTempLabels)
466 TM->setMCSaveTempLabels(true);
467 if (CodeGenOpts.NoDwarf2CFIAsm)
468 TM->setMCUseCFI(false);
469 if (!CodeGenOpts.NoDwarfDirectoryAsm)
470 TM->setMCUseDwarfDirectory(true);
471 if (CodeGenOpts.NoExecStack)
472 TM->setMCNoExecStack(true);
473
474 return TM;
475 }
476
AddEmitPasses(BackendAction Action,formatted_raw_ostream & OS,TargetMachine * TM)477 bool EmitAssemblyHelper::AddEmitPasses(BackendAction Action,
478 formatted_raw_ostream &OS,
479 TargetMachine *TM) {
480
481 // Create the code generator passes.
482 PassManager *PM = getCodeGenPasses(TM);
483
484 // Add LibraryInfo.
485 llvm::Triple TargetTriple(TheModule->getTargetTriple());
486 TargetLibraryInfo *TLI = new TargetLibraryInfo(TargetTriple);
487 if (!CodeGenOpts.SimplifyLibCalls)
488 TLI->disableAllFunctions();
489 PM->add(TLI);
490
491 // Add Target specific analysis passes.
492 TM->addAnalysisPasses(*PM);
493
494 // Normal mode, emit a .s or .o file by running the code generator. Note,
495 // this also adds codegenerator level optimization passes.
496 TargetMachine::CodeGenFileType CGFT = TargetMachine::CGFT_AssemblyFile;
497 if (Action == Backend_EmitObj)
498 CGFT = TargetMachine::CGFT_ObjectFile;
499 else if (Action == Backend_EmitMCNull)
500 CGFT = TargetMachine::CGFT_Null;
501 else
502 assert(Action == Backend_EmitAssembly && "Invalid action!");
503
504 // Add ObjC ARC final-cleanup optimizations. This is done as part of the
505 // "codegen" passes so that it isn't run multiple times when there is
506 // inlining happening.
507 if (LangOpts.ObjCAutoRefCount &&
508 CodeGenOpts.OptimizationLevel > 0)
509 PM->add(createObjCARCContractPass());
510
511 if (TM->addPassesToEmitFile(*PM, OS, CGFT,
512 /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
513 Diags.Report(diag::err_fe_unable_to_interface_with_target);
514 return false;
515 }
516
517 return true;
518 }
519
EmitAssembly(BackendAction Action,raw_ostream * OS)520 void EmitAssemblyHelper::EmitAssembly(BackendAction Action, raw_ostream *OS) {
521 TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : 0);
522 llvm::formatted_raw_ostream FormattedOS;
523
524 bool UsesCodeGen = (Action != Backend_EmitNothing &&
525 Action != Backend_EmitBC &&
526 Action != Backend_EmitLL);
527 TargetMachine *TM = CreateTargetMachine(UsesCodeGen);
528 if (UsesCodeGen && !TM) return;
529 llvm::OwningPtr<TargetMachine> TMOwner(CodeGenOpts.DisableFree ? 0 : TM);
530 CreatePasses(TM);
531
532 switch (Action) {
533 case Backend_EmitNothing:
534 break;
535
536 case Backend_EmitBC:
537 getPerModulePasses(TM)->add(createBitcodeWriterPass(*OS));
538 break;
539
540 case Backend_EmitLL:
541 FormattedOS.setStream(*OS, formatted_raw_ostream::PRESERVE_STREAM);
542 getPerModulePasses(TM)->add(createPrintModulePass(&FormattedOS));
543 break;
544
545 default:
546 FormattedOS.setStream(*OS, formatted_raw_ostream::PRESERVE_STREAM);
547 if (!AddEmitPasses(Action, FormattedOS, TM))
548 return;
549 }
550
551 // Before executing passes, print the final values of the LLVM options.
552 cl::PrintOptionValues();
553
554 // Run passes. For now we do all passes at once, but eventually we
555 // would like to have the option of streaming code generation.
556
557 if (PerFunctionPasses) {
558 PrettyStackTraceString CrashInfo("Per-function optimization");
559
560 PerFunctionPasses->doInitialization();
561 for (Module::iterator I = TheModule->begin(),
562 E = TheModule->end(); I != E; ++I)
563 if (!I->isDeclaration())
564 PerFunctionPasses->run(*I);
565 PerFunctionPasses->doFinalization();
566 }
567
568 if (PerModulePasses) {
569 PrettyStackTraceString CrashInfo("Per-module optimization passes");
570 PerModulePasses->run(*TheModule);
571 }
572
573 if (CodeGenPasses) {
574 PrettyStackTraceString CrashInfo("Code generation");
575 CodeGenPasses->run(*TheModule);
576 }
577 }
578
EmitBackendOutput(DiagnosticsEngine & Diags,const CodeGenOptions & CGOpts,const clang::TargetOptions & TOpts,const LangOptions & LOpts,Module * M,BackendAction Action,raw_ostream * OS)579 void clang::EmitBackendOutput(DiagnosticsEngine &Diags,
580 const CodeGenOptions &CGOpts,
581 const clang::TargetOptions &TOpts,
582 const LangOptions &LOpts,
583 Module *M,
584 BackendAction Action, raw_ostream *OS) {
585 EmitAssemblyHelper AsmHelper(Diags, CGOpts, TOpts, LOpts, M);
586
587 AsmHelper.EmitAssembly(Action, OS);
588 }
589