xref: /freebsd/contrib/llvm-project/clang/lib/CodeGen/BackendUtil.cpp (revision 6be3386466ab79a84b48429ae66244f21526d3df) 
1 //===--- BackendUtil.cpp - LLVM Backend Utilities -------------------------===//
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 #include "clang/CodeGen/BackendUtil.h"
10 #include "clang/Basic/CodeGenOptions.h"
11 #include "clang/Basic/Diagnostic.h"
12 #include "clang/Basic/LangOptions.h"
13 #include "clang/Basic/TargetOptions.h"
14 #include "clang/Frontend/FrontendDiagnostic.h"
15 #include "clang/Frontend/Utils.h"
16 #include "clang/Lex/HeaderSearchOptions.h"
17 #include "llvm/ADT/SmallSet.h"
18 #include "llvm/ADT/StringExtras.h"
19 #include "llvm/ADT/StringSwitch.h"
20 #include "llvm/ADT/Triple.h"
21 #include "llvm/Analysis/StackSafetyAnalysis.h"
22 #include "llvm/Analysis/TargetLibraryInfo.h"
23 #include "llvm/Analysis/TargetTransformInfo.h"
24 #include "llvm/Bitcode/BitcodeReader.h"
25 #include "llvm/Bitcode/BitcodeWriter.h"
26 #include "llvm/Bitcode/BitcodeWriterPass.h"
27 #include "llvm/CodeGen/RegAllocRegistry.h"
28 #include "llvm/CodeGen/SchedulerRegistry.h"
29 #include "llvm/CodeGen/TargetSubtargetInfo.h"
30 #include "llvm/IR/DataLayout.h"
31 #include "llvm/IR/IRPrintingPasses.h"
32 #include "llvm/IR/LegacyPassManager.h"
33 #include "llvm/IR/Module.h"
34 #include "llvm/IR/ModuleSummaryIndex.h"
35 #include "llvm/IR/PassManager.h"
36 #include "llvm/IR/Verifier.h"
37 #include "llvm/LTO/LTOBackend.h"
38 #include "llvm/MC/MCAsmInfo.h"
39 #include "llvm/MC/SubtargetFeature.h"
40 #include "llvm/Passes/PassBuilder.h"
41 #include "llvm/Passes/PassPlugin.h"
42 #include "llvm/Passes/StandardInstrumentations.h"
43 #include "llvm/Support/BuryPointer.h"
44 #include "llvm/Support/CommandLine.h"
45 #include "llvm/Support/MemoryBuffer.h"
46 #include "llvm/Support/PrettyStackTrace.h"
47 #include "llvm/Support/TargetRegistry.h"
48 #include "llvm/Support/TimeProfiler.h"
49 #include "llvm/Support/Timer.h"
50 #include "llvm/Support/ToolOutputFile.h"
51 #include "llvm/Support/raw_ostream.h"
52 #include "llvm/Target/TargetMachine.h"
53 #include "llvm/Target/TargetOptions.h"
54 #include "llvm/Transforms/Coroutines.h"
55 #include "llvm/Transforms/Coroutines/CoroCleanup.h"
56 #include "llvm/Transforms/Coroutines/CoroEarly.h"
57 #include "llvm/Transforms/Coroutines/CoroElide.h"
58 #include "llvm/Transforms/Coroutines/CoroSplit.h"
59 #include "llvm/Transforms/IPO.h"
60 #include "llvm/Transforms/IPO/AlwaysInliner.h"
61 #include "llvm/Transforms/IPO/LowerTypeTests.h"
62 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
63 #include "llvm/Transforms/IPO/ThinLTOBitcodeWriter.h"
64 #include "llvm/Transforms/InstCombine/InstCombine.h"
65 #include "llvm/Transforms/Instrumentation.h"
66 #include "llvm/Transforms/Instrumentation/AddressSanitizer.h"
67 #include "llvm/Transforms/Instrumentation/BoundsChecking.h"
68 #include "llvm/Transforms/Instrumentation/GCOVProfiler.h"
69 #include "llvm/Transforms/Instrumentation/HWAddressSanitizer.h"
70 #include "llvm/Transforms/Instrumentation/InstrProfiling.h"
71 #include "llvm/Transforms/Instrumentation/MemorySanitizer.h"
72 #include "llvm/Transforms/Instrumentation/SanitizerCoverage.h"
73 #include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
74 #include "llvm/Transforms/ObjCARC.h"
75 #include "llvm/Transforms/Scalar.h"
76 #include "llvm/Transforms/Scalar/GVN.h"
77 #include "llvm/Transforms/Utils.h"
78 #include "llvm/Transforms/Utils/CanonicalizeAliases.h"
79 #include "llvm/Transforms/Utils/EntryExitInstrumenter.h"
80 #include "llvm/Transforms/Utils/NameAnonGlobals.h"
81 #include "llvm/Transforms/Utils/SymbolRewriter.h"
82 #include "llvm/Transforms/Utils/UniqueInternalLinkageNames.h"
83 #include <memory>
84 using namespace clang;
85 using namespace llvm;
86 
87 #define HANDLE_EXTENSION(Ext)                                                  \
88   llvm::PassPluginLibraryInfo get##Ext##PluginInfo();
89 #include "llvm/Support/Extension.def"
90 
91 namespace {
92 
93 // Default filename used for profile generation.
94 static constexpr StringLiteral DefaultProfileGenName = "default_%m.profraw";
95 
96 class EmitAssemblyHelper {
97   DiagnosticsEngine &Diags;
98   const HeaderSearchOptions &HSOpts;
99   const CodeGenOptions &CodeGenOpts;
100   const clang::TargetOptions &TargetOpts;
101   const LangOptions &LangOpts;
102   Module *TheModule;
103 
104   Timer CodeGenerationTime;
105 
106   std::unique_ptr<raw_pwrite_stream> OS;
107 
108   TargetIRAnalysis getTargetIRAnalysis() const {
109     if (TM)
110       return TM->getTargetIRAnalysis();
111 
112     return TargetIRAnalysis();
113   }
114 
115   void CreatePasses(legacy::PassManager &MPM, legacy::FunctionPassManager &FPM);
116 
117   /// Generates the TargetMachine.
118   /// Leaves TM unchanged if it is unable to create the target machine.
119   /// Some of our clang tests specify triples which are not built
120   /// into clang. This is okay because these tests check the generated
121   /// IR, and they require DataLayout which depends on the triple.
122   /// In this case, we allow this method to fail and not report an error.
123   /// When MustCreateTM is used, we print an error if we are unable to load
124   /// the requested target.
125   void CreateTargetMachine(bool MustCreateTM);
126 
127   /// Add passes necessary to emit assembly or LLVM IR.
128   ///
129   /// \return True on success.
130   bool AddEmitPasses(legacy::PassManager &CodeGenPasses, BackendAction Action,
131                      raw_pwrite_stream &OS, raw_pwrite_stream *DwoOS);
132 
133   std::unique_ptr<llvm::ToolOutputFile> openOutputFile(StringRef Path) {
134     std::error_code EC;
135     auto F = std::make_unique<llvm::ToolOutputFile>(Path, EC,
136                                                      llvm::sys::fs::OF_None);
137     if (EC) {
138       Diags.Report(diag::err_fe_unable_to_open_output) << Path << EC.message();
139       F.reset();
140     }
141     return F;
142   }
143 
144 public:
145   EmitAssemblyHelper(DiagnosticsEngine &_Diags,
146                      const HeaderSearchOptions &HeaderSearchOpts,
147                      const CodeGenOptions &CGOpts,
148                      const clang::TargetOptions &TOpts,
149                      const LangOptions &LOpts, Module *M)
150       : Diags(_Diags), HSOpts(HeaderSearchOpts), CodeGenOpts(CGOpts),
151         TargetOpts(TOpts), LangOpts(LOpts), TheModule(M),
152         CodeGenerationTime("codegen", "Code Generation Time") {}
153 
154   ~EmitAssemblyHelper() {
155     if (CodeGenOpts.DisableFree)
156       BuryPointer(std::move(TM));
157   }
158 
159   std::unique_ptr<TargetMachine> TM;
160 
161   void EmitAssembly(BackendAction Action,
162                     std::unique_ptr<raw_pwrite_stream> OS);
163 
164   void EmitAssemblyWithNewPassManager(BackendAction Action,
165                                       std::unique_ptr<raw_pwrite_stream> OS);
166 };
167 
168 // We need this wrapper to access LangOpts and CGOpts from extension functions
169 // that we add to the PassManagerBuilder.
170 class PassManagerBuilderWrapper : public PassManagerBuilder {
171 public:
172   PassManagerBuilderWrapper(const Triple &TargetTriple,
173                             const CodeGenOptions &CGOpts,
174                             const LangOptions &LangOpts)
175       : PassManagerBuilder(), TargetTriple(TargetTriple), CGOpts(CGOpts),
176         LangOpts(LangOpts) {}
177   const Triple &getTargetTriple() const { return TargetTriple; }
178   const CodeGenOptions &getCGOpts() const { return CGOpts; }
179   const LangOptions &getLangOpts() const { return LangOpts; }
180 
181 private:
182   const Triple &TargetTriple;
183   const CodeGenOptions &CGOpts;
184   const LangOptions &LangOpts;
185 };
186 }
187 
188 static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
189   if (Builder.OptLevel > 0)
190     PM.add(createObjCARCAPElimPass());
191 }
192 
193 static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
194   if (Builder.OptLevel > 0)
195     PM.add(createObjCARCExpandPass());
196 }
197 
198 static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
199   if (Builder.OptLevel > 0)
200     PM.add(createObjCARCOptPass());
201 }
202 
203 static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder,
204                                      legacy::PassManagerBase &PM) {
205   PM.add(createAddDiscriminatorsPass());
206 }
207 
208 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
209                                   legacy::PassManagerBase &PM) {
210   PM.add(createBoundsCheckingLegacyPass());
211 }
212 
213 static SanitizerCoverageOptions
214 getSancovOptsFromCGOpts(const CodeGenOptions &CGOpts) {
215   SanitizerCoverageOptions Opts;
216   Opts.CoverageType =
217       static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
218   Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
219   Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
220   Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
221   Opts.TraceDiv = CGOpts.SanitizeCoverageTraceDiv;
222   Opts.TraceGep = CGOpts.SanitizeCoverageTraceGep;
223   Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
224   Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
225   Opts.TracePCGuard = CGOpts.SanitizeCoverageTracePCGuard;
226   Opts.NoPrune = CGOpts.SanitizeCoverageNoPrune;
227   Opts.Inline8bitCounters = CGOpts.SanitizeCoverageInline8bitCounters;
228   Opts.InlineBoolFlag = CGOpts.SanitizeCoverageInlineBoolFlag;
229   Opts.PCTable = CGOpts.SanitizeCoveragePCTable;
230   Opts.StackDepth = CGOpts.SanitizeCoverageStackDepth;
231   return Opts;
232 }
233 
234 static void addSanitizerCoveragePass(const PassManagerBuilder &Builder,
235                                      legacy::PassManagerBase &PM) {
236   const PassManagerBuilderWrapper &BuilderWrapper =
237       static_cast<const PassManagerBuilderWrapper &>(Builder);
238   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
239   auto Opts = getSancovOptsFromCGOpts(CGOpts);
240   PM.add(createModuleSanitizerCoverageLegacyPassPass(
241       Opts, CGOpts.SanitizeCoverageAllowlistFiles,
242       CGOpts.SanitizeCoverageBlocklistFiles));
243 }
244 
245 // Check if ASan should use GC-friendly instrumentation for globals.
246 // First of all, there is no point if -fdata-sections is off (expect for MachO,
247 // where this is not a factor). Also, on ELF this feature requires an assembler
248 // extension that only works with -integrated-as at the moment.
249 static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
250   if (!CGOpts.SanitizeAddressGlobalsDeadStripping)
251     return false;
252   switch (T.getObjectFormat()) {
253   case Triple::MachO:
254   case Triple::COFF:
255     return true;
256   case Triple::ELF:
257     return CGOpts.DataSections && !CGOpts.DisableIntegratedAS;
258   case Triple::XCOFF:
259     llvm::report_fatal_error("ASan not implemented for XCOFF.");
260   case Triple::Wasm:
261   case Triple::UnknownObjectFormat:
262     break;
263   }
264   return false;
265 }
266 
267 static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
268                                       legacy::PassManagerBase &PM) {
269   const PassManagerBuilderWrapper &BuilderWrapper =
270       static_cast<const PassManagerBuilderWrapper&>(Builder);
271   const Triple &T = BuilderWrapper.getTargetTriple();
272   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
273   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Address);
274   bool UseAfterScope = CGOpts.SanitizeAddressUseAfterScope;
275   bool UseOdrIndicator = CGOpts.SanitizeAddressUseOdrIndicator;
276   bool UseGlobalsGC = asanUseGlobalsGC(T, CGOpts);
277   PM.add(createAddressSanitizerFunctionPass(/*CompileKernel*/ false, Recover,
278                                             UseAfterScope));
279   PM.add(createModuleAddressSanitizerLegacyPassPass(
280       /*CompileKernel*/ false, Recover, UseGlobalsGC, UseOdrIndicator));
281 }
282 
283 static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder,
284                                             legacy::PassManagerBase &PM) {
285   PM.add(createAddressSanitizerFunctionPass(
286       /*CompileKernel*/ true, /*Recover*/ true, /*UseAfterScope*/ false));
287   PM.add(createModuleAddressSanitizerLegacyPassPass(
288       /*CompileKernel*/ true, /*Recover*/ true, /*UseGlobalsGC*/ true,
289       /*UseOdrIndicator*/ false));
290 }
291 
292 static void addHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
293                                             legacy::PassManagerBase &PM) {
294   const PassManagerBuilderWrapper &BuilderWrapper =
295       static_cast<const PassManagerBuilderWrapper &>(Builder);
296   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
297   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::HWAddress);
298   PM.add(
299       createHWAddressSanitizerLegacyPassPass(/*CompileKernel*/ false, Recover));
300 }
301 
302 static void addKernelHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
303                                             legacy::PassManagerBase &PM) {
304   PM.add(createHWAddressSanitizerLegacyPassPass(
305       /*CompileKernel*/ true, /*Recover*/ true));
306 }
307 
308 static void addGeneralOptsForMemorySanitizer(const PassManagerBuilder &Builder,
309                                              legacy::PassManagerBase &PM,
310                                              bool CompileKernel) {
311   const PassManagerBuilderWrapper &BuilderWrapper =
312       static_cast<const PassManagerBuilderWrapper&>(Builder);
313   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
314   int TrackOrigins = CGOpts.SanitizeMemoryTrackOrigins;
315   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Memory);
316   PM.add(createMemorySanitizerLegacyPassPass(
317       MemorySanitizerOptions{TrackOrigins, Recover, CompileKernel}));
318 
319   // MemorySanitizer inserts complex instrumentation that mostly follows
320   // the logic of the original code, but operates on "shadow" values.
321   // It can benefit from re-running some general purpose optimization passes.
322   if (Builder.OptLevel > 0) {
323     PM.add(createEarlyCSEPass());
324     PM.add(createReassociatePass());
325     PM.add(createLICMPass());
326     PM.add(createGVNPass());
327     PM.add(createInstructionCombiningPass());
328     PM.add(createDeadStoreEliminationPass());
329   }
330 }
331 
332 static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
333                                    legacy::PassManagerBase &PM) {
334   addGeneralOptsForMemorySanitizer(Builder, PM, /*CompileKernel*/ false);
335 }
336 
337 static void addKernelMemorySanitizerPass(const PassManagerBuilder &Builder,
338                                          legacy::PassManagerBase &PM) {
339   addGeneralOptsForMemorySanitizer(Builder, PM, /*CompileKernel*/ true);
340 }
341 
342 static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
343                                    legacy::PassManagerBase &PM) {
344   PM.add(createThreadSanitizerLegacyPassPass());
345 }
346 
347 static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder,
348                                      legacy::PassManagerBase &PM) {
349   const PassManagerBuilderWrapper &BuilderWrapper =
350       static_cast<const PassManagerBuilderWrapper&>(Builder);
351   const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
352   PM.add(createDataFlowSanitizerPass(LangOpts.SanitizerBlacklistFiles));
353 }
354 
355 static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
356                                          const CodeGenOptions &CodeGenOpts) {
357   TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
358 
359   switch (CodeGenOpts.getVecLib()) {
360   case CodeGenOptions::Accelerate:
361     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate);
362     break;
363   case CodeGenOptions::MASSV:
364     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::MASSV);
365     break;
366   case CodeGenOptions::SVML:
367     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SVML);
368     break;
369   default:
370     break;
371   }
372   return TLII;
373 }
374 
375 static void addSymbolRewriterPass(const CodeGenOptions &Opts,
376                                   legacy::PassManager *MPM) {
377   llvm::SymbolRewriter::RewriteDescriptorList DL;
378 
379   llvm::SymbolRewriter::RewriteMapParser MapParser;
380   for (const auto &MapFile : Opts.RewriteMapFiles)
381     MapParser.parse(MapFile, &DL);
382 
383   MPM->add(createRewriteSymbolsPass(DL));
384 }
385 
386 static CodeGenOpt::Level getCGOptLevel(const CodeGenOptions &CodeGenOpts) {
387   switch (CodeGenOpts.OptimizationLevel) {
388   default:
389     llvm_unreachable("Invalid optimization level!");
390   case 0:
391     return CodeGenOpt::None;
392   case 1:
393     return CodeGenOpt::Less;
394   case 2:
395     return CodeGenOpt::Default; // O2/Os/Oz
396   case 3:
397     return CodeGenOpt::Aggressive;
398   }
399 }
400 
401 static Optional<llvm::CodeModel::Model>
402 getCodeModel(const CodeGenOptions &CodeGenOpts) {
403   unsigned CodeModel = llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
404                            .Case("tiny", llvm::CodeModel::Tiny)
405                            .Case("small", llvm::CodeModel::Small)
406                            .Case("kernel", llvm::CodeModel::Kernel)
407                            .Case("medium", llvm::CodeModel::Medium)
408                            .Case("large", llvm::CodeModel::Large)
409                            .Case("default", ~1u)
410                            .Default(~0u);
411   assert(CodeModel != ~0u && "invalid code model!");
412   if (CodeModel == ~1u)
413     return None;
414   return static_cast<llvm::CodeModel::Model>(CodeModel);
415 }
416 
417 static CodeGenFileType getCodeGenFileType(BackendAction Action) {
418   if (Action == Backend_EmitObj)
419     return CGFT_ObjectFile;
420   else if (Action == Backend_EmitMCNull)
421     return CGFT_Null;
422   else {
423     assert(Action == Backend_EmitAssembly && "Invalid action!");
424     return CGFT_AssemblyFile;
425   }
426 }
427 
428 static void initTargetOptions(DiagnosticsEngine &Diags,
429                               llvm::TargetOptions &Options,
430                               const CodeGenOptions &CodeGenOpts,
431                               const clang::TargetOptions &TargetOpts,
432                               const LangOptions &LangOpts,
433                               const HeaderSearchOptions &HSOpts) {
434   Options.ThreadModel =
435       llvm::StringSwitch<llvm::ThreadModel::Model>(CodeGenOpts.ThreadModel)
436           .Case("posix", llvm::ThreadModel::POSIX)
437           .Case("single", llvm::ThreadModel::Single);
438 
439   // Set float ABI type.
440   assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
441           CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
442          "Invalid Floating Point ABI!");
443   Options.FloatABIType =
444       llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
445           .Case("soft", llvm::FloatABI::Soft)
446           .Case("softfp", llvm::FloatABI::Soft)
447           .Case("hard", llvm::FloatABI::Hard)
448           .Default(llvm::FloatABI::Default);
449 
450   // Set FP fusion mode.
451   switch (LangOpts.getDefaultFPContractMode()) {
452   case LangOptions::FPM_Off:
453     // Preserve any contraction performed by the front-end.  (Strict performs
454     // splitting of the muladd intrinsic in the backend.)
455     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
456     break;
457   case LangOptions::FPM_On:
458     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
459     break;
460   case LangOptions::FPM_Fast:
461     Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
462     break;
463   }
464 
465   Options.UseInitArray = CodeGenOpts.UseInitArray;
466   Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
467   Options.CompressDebugSections = CodeGenOpts.getCompressDebugSections();
468   Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
469 
470   // Set EABI version.
471   Options.EABIVersion = TargetOpts.EABIVersion;
472 
473   if (LangOpts.SjLjExceptions)
474     Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
475   if (LangOpts.SEHExceptions)
476     Options.ExceptionModel = llvm::ExceptionHandling::WinEH;
477   if (LangOpts.DWARFExceptions)
478     Options.ExceptionModel = llvm::ExceptionHandling::DwarfCFI;
479   if (LangOpts.WasmExceptions)
480     Options.ExceptionModel = llvm::ExceptionHandling::Wasm;
481 
482   Options.NoInfsFPMath = LangOpts.NoHonorInfs;
483   Options.NoNaNsFPMath = LangOpts.NoHonorNaNs;
484   Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
485   Options.UnsafeFPMath = LangOpts.UnsafeFPMath;
486   Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
487 
488   Options.BBSections =
489       llvm::StringSwitch<llvm::BasicBlockSection>(CodeGenOpts.BBSections)
490           .Case("all", llvm::BasicBlockSection::All)
491           .Case("labels", llvm::BasicBlockSection::Labels)
492           .StartsWith("list=", llvm::BasicBlockSection::List)
493           .Case("none", llvm::BasicBlockSection::None)
494           .Default(llvm::BasicBlockSection::None);
495 
496   if (Options.BBSections == llvm::BasicBlockSection::List) {
497     ErrorOr<std::unique_ptr<MemoryBuffer>> MBOrErr =
498         MemoryBuffer::getFile(CodeGenOpts.BBSections.substr(5));
499     if (!MBOrErr)
500       Diags.Report(diag::err_fe_unable_to_load_basic_block_sections_file)
501           << MBOrErr.getError().message();
502     else
503       Options.BBSectionsFuncListBuf = std::move(*MBOrErr);
504   }
505 
506   Options.FunctionSections = CodeGenOpts.FunctionSections;
507   Options.DataSections = CodeGenOpts.DataSections;
508   Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
509   Options.UniqueBasicBlockSectionNames =
510       CodeGenOpts.UniqueBasicBlockSectionNames;
511   Options.TLSSize = CodeGenOpts.TLSSize;
512   Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
513   Options.ExplicitEmulatedTLS = CodeGenOpts.ExplicitEmulatedTLS;
514   Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
515   Options.EmitStackSizeSection = CodeGenOpts.StackSizeSection;
516   Options.EmitAddrsig = CodeGenOpts.Addrsig;
517   Options.ForceDwarfFrameSection = CodeGenOpts.ForceDwarfFrameSection;
518   Options.EmitCallSiteInfo = CodeGenOpts.EmitCallSiteInfo;
519   Options.XRayOmitFunctionIndex = CodeGenOpts.XRayOmitFunctionIndex;
520 
521   Options.MCOptions.SplitDwarfFile = CodeGenOpts.SplitDwarfFile;
522   Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
523   Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
524   Options.MCOptions.MCUseDwarfDirectory = !CodeGenOpts.NoDwarfDirectoryAsm;
525   Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
526   Options.MCOptions.MCIncrementalLinkerCompatible =
527       CodeGenOpts.IncrementalLinkerCompatible;
528   Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
529   Options.MCOptions.MCNoWarn = CodeGenOpts.NoWarn;
530   Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
531   Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
532   Options.MCOptions.ABIName = TargetOpts.ABI;
533   for (const auto &Entry : HSOpts.UserEntries)
534     if (!Entry.IsFramework &&
535         (Entry.Group == frontend::IncludeDirGroup::Quoted ||
536          Entry.Group == frontend::IncludeDirGroup::Angled ||
537          Entry.Group == frontend::IncludeDirGroup::System))
538       Options.MCOptions.IASSearchPaths.push_back(
539           Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
540   Options.MCOptions.Argv0 = CodeGenOpts.Argv0;
541   Options.MCOptions.CommandLineArgs = CodeGenOpts.CommandLineArgs;
542 }
543 static Optional<GCOVOptions> getGCOVOptions(const CodeGenOptions &CodeGenOpts) {
544   if (CodeGenOpts.DisableGCov)
545     return None;
546   if (!CodeGenOpts.EmitGcovArcs && !CodeGenOpts.EmitGcovNotes)
547     return None;
548   // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
549   // LLVM's -default-gcov-version flag is set to something invalid.
550   GCOVOptions Options;
551   Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
552   Options.EmitData = CodeGenOpts.EmitGcovArcs;
553   llvm::copy(CodeGenOpts.CoverageVersion, std::begin(Options.Version));
554   Options.NoRedZone = CodeGenOpts.DisableRedZone;
555   Options.Filter = CodeGenOpts.ProfileFilterFiles;
556   Options.Exclude = CodeGenOpts.ProfileExcludeFiles;
557   return Options;
558 }
559 
560 static Optional<InstrProfOptions>
561 getInstrProfOptions(const CodeGenOptions &CodeGenOpts,
562                     const LangOptions &LangOpts) {
563   if (!CodeGenOpts.hasProfileClangInstr())
564     return None;
565   InstrProfOptions Options;
566   Options.NoRedZone = CodeGenOpts.DisableRedZone;
567   Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
568 
569   // TODO: Surface the option to emit atomic profile counter increments at
570   // the driver level.
571   Options.Atomic = LangOpts.Sanitize.has(SanitizerKind::Thread);
572   return Options;
573 }
574 
575 void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
576                                       legacy::FunctionPassManager &FPM) {
577   // Handle disabling of all LLVM passes, where we want to preserve the
578   // internal module before any optimization.
579   if (CodeGenOpts.DisableLLVMPasses)
580     return;
581 
582   // Figure out TargetLibraryInfo.  This needs to be added to MPM and FPM
583   // manually (and not via PMBuilder), since some passes (eg. InstrProfiling)
584   // are inserted before PMBuilder ones - they'd get the default-constructed
585   // TLI with an unknown target otherwise.
586   Triple TargetTriple(TheModule->getTargetTriple());
587   std::unique_ptr<TargetLibraryInfoImpl> TLII(
588       createTLII(TargetTriple, CodeGenOpts));
589 
590   // If we reached here with a non-empty index file name, then the index file
591   // was empty and we are not performing ThinLTO backend compilation (used in
592   // testing in a distributed build environment). Drop any the type test
593   // assume sequences inserted for whole program vtables so that codegen doesn't
594   // complain.
595   if (!CodeGenOpts.ThinLTOIndexFile.empty())
596     MPM.add(createLowerTypeTestsPass(/*ExportSummary=*/nullptr,
597                                      /*ImportSummary=*/nullptr,
598                                      /*DropTypeTests=*/true));
599 
600   PassManagerBuilderWrapper PMBuilder(TargetTriple, CodeGenOpts, LangOpts);
601 
602   // At O0 and O1 we only run the always inliner which is more efficient. At
603   // higher optimization levels we run the normal inliner.
604   if (CodeGenOpts.OptimizationLevel <= 1) {
605     bool InsertLifetimeIntrinsics = ((CodeGenOpts.OptimizationLevel != 0 &&
606                                       !CodeGenOpts.DisableLifetimeMarkers) ||
607                                      LangOpts.Coroutines);
608     PMBuilder.Inliner = createAlwaysInlinerLegacyPass(InsertLifetimeIntrinsics);
609   } else {
610     // We do not want to inline hot callsites for SamplePGO module-summary build
611     // because profile annotation will happen again in ThinLTO backend, and we
612     // want the IR of the hot path to match the profile.
613     PMBuilder.Inliner = createFunctionInliningPass(
614         CodeGenOpts.OptimizationLevel, CodeGenOpts.OptimizeSize,
615         (!CodeGenOpts.SampleProfileFile.empty() &&
616          CodeGenOpts.PrepareForThinLTO));
617   }
618 
619   PMBuilder.OptLevel = CodeGenOpts.OptimizationLevel;
620   PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
621   PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
622   PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
623   // Only enable CGProfilePass when using integrated assembler, since
624   // non-integrated assemblers don't recognize .cgprofile section.
625   PMBuilder.CallGraphProfile = !CodeGenOpts.DisableIntegratedAS;
626 
627   PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
628   // Loop interleaving in the loop vectorizer has historically been set to be
629   // enabled when loop unrolling is enabled.
630   PMBuilder.LoopsInterleaved = CodeGenOpts.UnrollLoops;
631   PMBuilder.MergeFunctions = CodeGenOpts.MergeFunctions;
632   PMBuilder.PrepareForThinLTO = CodeGenOpts.PrepareForThinLTO;
633   PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
634   PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
635 
636   MPM.add(new TargetLibraryInfoWrapperPass(*TLII));
637 
638   if (TM)
639     TM->adjustPassManager(PMBuilder);
640 
641   if (CodeGenOpts.DebugInfoForProfiling ||
642       !CodeGenOpts.SampleProfileFile.empty())
643     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
644                            addAddDiscriminatorsPass);
645 
646   // In ObjC ARC mode, add the main ARC optimization passes.
647   if (LangOpts.ObjCAutoRefCount) {
648     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
649                            addObjCARCExpandPass);
650     PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
651                            addObjCARCAPElimPass);
652     PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
653                            addObjCARCOptPass);
654   }
655 
656   if (LangOpts.Coroutines)
657     addCoroutinePassesToExtensionPoints(PMBuilder);
658 
659   if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds)) {
660     PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
661                            addBoundsCheckingPass);
662     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
663                            addBoundsCheckingPass);
664   }
665 
666   if (CodeGenOpts.SanitizeCoverageType ||
667       CodeGenOpts.SanitizeCoverageIndirectCalls ||
668       CodeGenOpts.SanitizeCoverageTraceCmp) {
669     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
670                            addSanitizerCoveragePass);
671     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
672                            addSanitizerCoveragePass);
673   }
674 
675   if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
676     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
677                            addAddressSanitizerPasses);
678     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
679                            addAddressSanitizerPasses);
680   }
681 
682   if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
683     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
684                            addKernelAddressSanitizerPasses);
685     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
686                            addKernelAddressSanitizerPasses);
687   }
688 
689   if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
690     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
691                            addHWAddressSanitizerPasses);
692     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
693                            addHWAddressSanitizerPasses);
694   }
695 
696   if (LangOpts.Sanitize.has(SanitizerKind::KernelHWAddress)) {
697     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
698                            addKernelHWAddressSanitizerPasses);
699     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
700                            addKernelHWAddressSanitizerPasses);
701   }
702 
703   if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
704     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
705                            addMemorySanitizerPass);
706     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
707                            addMemorySanitizerPass);
708   }
709 
710   if (LangOpts.Sanitize.has(SanitizerKind::KernelMemory)) {
711     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
712                            addKernelMemorySanitizerPass);
713     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
714                            addKernelMemorySanitizerPass);
715   }
716 
717   if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
718     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
719                            addThreadSanitizerPass);
720     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
721                            addThreadSanitizerPass);
722   }
723 
724   if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
725     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
726                            addDataFlowSanitizerPass);
727     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
728                            addDataFlowSanitizerPass);
729   }
730 
731   // Set up the per-function pass manager.
732   FPM.add(new TargetLibraryInfoWrapperPass(*TLII));
733   if (CodeGenOpts.VerifyModule)
734     FPM.add(createVerifierPass());
735 
736   // Set up the per-module pass manager.
737   if (!CodeGenOpts.RewriteMapFiles.empty())
738     addSymbolRewriterPass(CodeGenOpts, &MPM);
739 
740   // Add UniqueInternalLinkageNames Pass which renames internal linkage symbols
741   // with unique names.
742   if (CodeGenOpts.UniqueInternalLinkageNames) {
743     MPM.add(createUniqueInternalLinkageNamesPass());
744   }
745 
746   if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts)) {
747     MPM.add(createGCOVProfilerPass(*Options));
748     if (CodeGenOpts.getDebugInfo() == codegenoptions::NoDebugInfo)
749       MPM.add(createStripSymbolsPass(true));
750   }
751 
752   if (Optional<InstrProfOptions> Options =
753           getInstrProfOptions(CodeGenOpts, LangOpts))
754     MPM.add(createInstrProfilingLegacyPass(*Options, false));
755 
756   bool hasIRInstr = false;
757   if (CodeGenOpts.hasProfileIRInstr()) {
758     PMBuilder.EnablePGOInstrGen = true;
759     hasIRInstr = true;
760   }
761   if (CodeGenOpts.hasProfileCSIRInstr()) {
762     assert(!CodeGenOpts.hasProfileCSIRUse() &&
763            "Cannot have both CSProfileUse pass and CSProfileGen pass at the "
764            "same time");
765     assert(!hasIRInstr &&
766            "Cannot have both ProfileGen pass and CSProfileGen pass at the "
767            "same time");
768     PMBuilder.EnablePGOCSInstrGen = true;
769     hasIRInstr = true;
770   }
771   if (hasIRInstr) {
772     if (!CodeGenOpts.InstrProfileOutput.empty())
773       PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
774     else
775       PMBuilder.PGOInstrGen = std::string(DefaultProfileGenName);
776   }
777   if (CodeGenOpts.hasProfileIRUse()) {
778     PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
779     PMBuilder.EnablePGOCSInstrUse = CodeGenOpts.hasProfileCSIRUse();
780   }
781 
782   if (!CodeGenOpts.SampleProfileFile.empty())
783     PMBuilder.PGOSampleUse = CodeGenOpts.SampleProfileFile;
784 
785   PMBuilder.populateFunctionPassManager(FPM);
786   PMBuilder.populateModulePassManager(MPM);
787 }
788 
789 static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
790   SmallVector<const char *, 16> BackendArgs;
791   BackendArgs.push_back("clang"); // Fake program name.
792   if (!CodeGenOpts.DebugPass.empty()) {
793     BackendArgs.push_back("-debug-pass");
794     BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
795   }
796   if (!CodeGenOpts.LimitFloatPrecision.empty()) {
797     BackendArgs.push_back("-limit-float-precision");
798     BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
799   }
800   BackendArgs.push_back(nullptr);
801   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
802                                     BackendArgs.data());
803 }
804 
805 void EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
806   // Create the TargetMachine for generating code.
807   std::string Error;
808   std::string Triple = TheModule->getTargetTriple();
809   const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
810   if (!TheTarget) {
811     if (MustCreateTM)
812       Diags.Report(diag::err_fe_unable_to_create_target) << Error;
813     return;
814   }
815 
816   Optional<llvm::CodeModel::Model> CM = getCodeModel(CodeGenOpts);
817   std::string FeaturesStr =
818       llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
819   llvm::Reloc::Model RM = CodeGenOpts.RelocationModel;
820   CodeGenOpt::Level OptLevel = getCGOptLevel(CodeGenOpts);
821 
822   llvm::TargetOptions Options;
823   initTargetOptions(Diags, Options, CodeGenOpts, TargetOpts, LangOpts, HSOpts);
824   TM.reset(TheTarget->createTargetMachine(Triple, TargetOpts.CPU, FeaturesStr,
825                                           Options, RM, CM, OptLevel));
826 }
827 
828 bool EmitAssemblyHelper::AddEmitPasses(legacy::PassManager &CodeGenPasses,
829                                        BackendAction Action,
830                                        raw_pwrite_stream &OS,
831                                        raw_pwrite_stream *DwoOS) {
832   // Add LibraryInfo.
833   llvm::Triple TargetTriple(TheModule->getTargetTriple());
834   std::unique_ptr<TargetLibraryInfoImpl> TLII(
835       createTLII(TargetTriple, CodeGenOpts));
836   CodeGenPasses.add(new TargetLibraryInfoWrapperPass(*TLII));
837 
838   // Normal mode, emit a .s or .o file by running the code generator. Note,
839   // this also adds codegenerator level optimization passes.
840   CodeGenFileType CGFT = getCodeGenFileType(Action);
841 
842   // Add ObjC ARC final-cleanup optimizations. This is done as part of the
843   // "codegen" passes so that it isn't run multiple times when there is
844   // inlining happening.
845   if (CodeGenOpts.OptimizationLevel > 0)
846     CodeGenPasses.add(createObjCARCContractPass());
847 
848   if (TM->addPassesToEmitFile(CodeGenPasses, OS, DwoOS, CGFT,
849                               /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
850     Diags.Report(diag::err_fe_unable_to_interface_with_target);
851     return false;
852   }
853 
854   return true;
855 }
856 
857 void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
858                                       std::unique_ptr<raw_pwrite_stream> OS) {
859   TimeRegion Region(FrontendTimesIsEnabled ? &CodeGenerationTime : nullptr);
860 
861   setCommandLineOpts(CodeGenOpts);
862 
863   bool UsesCodeGen = (Action != Backend_EmitNothing &&
864                       Action != Backend_EmitBC &&
865                       Action != Backend_EmitLL);
866   CreateTargetMachine(UsesCodeGen);
867 
868   if (UsesCodeGen && !TM)
869     return;
870   if (TM)
871     TheModule->setDataLayout(TM->createDataLayout());
872 
873   legacy::PassManager PerModulePasses;
874   PerModulePasses.add(
875       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
876 
877   legacy::FunctionPassManager PerFunctionPasses(TheModule);
878   PerFunctionPasses.add(
879       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
880 
881   CreatePasses(PerModulePasses, PerFunctionPasses);
882 
883   legacy::PassManager CodeGenPasses;
884   CodeGenPasses.add(
885       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
886 
887   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
888 
889   switch (Action) {
890   case Backend_EmitNothing:
891     break;
892 
893   case Backend_EmitBC:
894     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
895       if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
896         ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
897         if (!ThinLinkOS)
898           return;
899       }
900       TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
901                                CodeGenOpts.EnableSplitLTOUnit);
902       PerModulePasses.add(createWriteThinLTOBitcodePass(
903           *OS, ThinLinkOS ? &ThinLinkOS->os() : nullptr));
904     } else {
905       // Emit a module summary by default for Regular LTO except for ld64
906       // targets
907       bool EmitLTOSummary =
908           (CodeGenOpts.PrepareForLTO &&
909            !CodeGenOpts.DisableLLVMPasses &&
910            llvm::Triple(TheModule->getTargetTriple()).getVendor() !=
911                llvm::Triple::Apple);
912       if (EmitLTOSummary) {
913         if (!TheModule->getModuleFlag("ThinLTO"))
914           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
915         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
916                                  uint32_t(1));
917       }
918 
919       PerModulePasses.add(createBitcodeWriterPass(
920           *OS, CodeGenOpts.EmitLLVMUseLists, EmitLTOSummary));
921     }
922     break;
923 
924   case Backend_EmitLL:
925     PerModulePasses.add(
926         createPrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
927     break;
928 
929   default:
930     if (!CodeGenOpts.SplitDwarfOutput.empty()) {
931       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfOutput);
932       if (!DwoOS)
933         return;
934     }
935     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
936                        DwoOS ? &DwoOS->os() : nullptr))
937       return;
938   }
939 
940   // Before executing passes, print the final values of the LLVM options.
941   cl::PrintOptionValues();
942 
943   // Run passes. For now we do all passes at once, but eventually we
944   // would like to have the option of streaming code generation.
945 
946   {
947     PrettyStackTraceString CrashInfo("Per-function optimization");
948     llvm::TimeTraceScope TimeScope("PerFunctionPasses");
949 
950     PerFunctionPasses.doInitialization();
951     for (Function &F : *TheModule)
952       if (!F.isDeclaration())
953         PerFunctionPasses.run(F);
954     PerFunctionPasses.doFinalization();
955   }
956 
957   {
958     PrettyStackTraceString CrashInfo("Per-module optimization passes");
959     llvm::TimeTraceScope TimeScope("PerModulePasses");
960     PerModulePasses.run(*TheModule);
961   }
962 
963   {
964     PrettyStackTraceString CrashInfo("Code generation");
965     llvm::TimeTraceScope TimeScope("CodeGenPasses");
966     CodeGenPasses.run(*TheModule);
967   }
968 
969   if (ThinLinkOS)
970     ThinLinkOS->keep();
971   if (DwoOS)
972     DwoOS->keep();
973 }
974 
975 static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
976   switch (Opts.OptimizationLevel) {
977   default:
978     llvm_unreachable("Invalid optimization level!");
979 
980   case 1:
981     return PassBuilder::OptimizationLevel::O1;
982 
983   case 2:
984     switch (Opts.OptimizeSize) {
985     default:
986       llvm_unreachable("Invalid optimization level for size!");
987 
988     case 0:
989       return PassBuilder::OptimizationLevel::O2;
990 
991     case 1:
992       return PassBuilder::OptimizationLevel::Os;
993 
994     case 2:
995       return PassBuilder::OptimizationLevel::Oz;
996     }
997 
998   case 3:
999     return PassBuilder::OptimizationLevel::O3;
1000   }
1001 }
1002 
1003 static void addCoroutinePassesAtO0(ModulePassManager &MPM,
1004                                    const LangOptions &LangOpts,
1005                                    const CodeGenOptions &CodeGenOpts) {
1006   if (!LangOpts.Coroutines)
1007     return;
1008 
1009   MPM.addPass(createModuleToFunctionPassAdaptor(CoroEarlyPass()));
1010 
1011   CGSCCPassManager CGPM(CodeGenOpts.DebugPassManager);
1012   CGPM.addPass(CoroSplitPass());
1013   CGPM.addPass(createCGSCCToFunctionPassAdaptor(CoroElidePass()));
1014   MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPM)));
1015 
1016   MPM.addPass(createModuleToFunctionPassAdaptor(CoroCleanupPass()));
1017 }
1018 
1019 static void addSanitizersAtO0(ModulePassManager &MPM,
1020                               const Triple &TargetTriple,
1021                               const LangOptions &LangOpts,
1022                               const CodeGenOptions &CodeGenOpts) {
1023   if (CodeGenOpts.SanitizeCoverageType ||
1024       CodeGenOpts.SanitizeCoverageIndirectCalls ||
1025       CodeGenOpts.SanitizeCoverageTraceCmp) {
1026     auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
1027     MPM.addPass(ModuleSanitizerCoveragePass(
1028         SancovOpts, CodeGenOpts.SanitizeCoverageAllowlistFiles,
1029         CodeGenOpts.SanitizeCoverageBlocklistFiles));
1030   }
1031 
1032   auto ASanPass = [&](SanitizerMask Mask, bool CompileKernel) {
1033     MPM.addPass(RequireAnalysisPass<ASanGlobalsMetadataAnalysis, Module>());
1034     bool Recover = CodeGenOpts.SanitizeRecover.has(Mask);
1035     MPM.addPass(createModuleToFunctionPassAdaptor(AddressSanitizerPass(
1036         CompileKernel, Recover, CodeGenOpts.SanitizeAddressUseAfterScope)));
1037     bool ModuleUseAfterScope = asanUseGlobalsGC(TargetTriple, CodeGenOpts);
1038     MPM.addPass(
1039         ModuleAddressSanitizerPass(CompileKernel, Recover, ModuleUseAfterScope,
1040                                    CodeGenOpts.SanitizeAddressUseOdrIndicator));
1041   };
1042 
1043   if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
1044     ASanPass(SanitizerKind::Address, /*CompileKernel=*/false);
1045   }
1046 
1047   if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
1048     ASanPass(SanitizerKind::KernelAddress, /*CompileKernel=*/true);
1049   }
1050 
1051   if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
1052     bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::Memory);
1053     int TrackOrigins = CodeGenOpts.SanitizeMemoryTrackOrigins;
1054     MPM.addPass(MemorySanitizerPass({TrackOrigins, Recover, false}));
1055     MPM.addPass(createModuleToFunctionPassAdaptor(
1056         MemorySanitizerPass({TrackOrigins, Recover, false})));
1057   }
1058 
1059   if (LangOpts.Sanitize.has(SanitizerKind::KernelMemory)) {
1060     MPM.addPass(createModuleToFunctionPassAdaptor(
1061         MemorySanitizerPass({0, false, /*Kernel=*/true})));
1062   }
1063 
1064   if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
1065     MPM.addPass(ThreadSanitizerPass());
1066     MPM.addPass(createModuleToFunctionPassAdaptor(ThreadSanitizerPass()));
1067   }
1068 }
1069 
1070 /// A clean version of `EmitAssembly` that uses the new pass manager.
1071 ///
1072 /// Not all features are currently supported in this system, but where
1073 /// necessary it falls back to the legacy pass manager to at least provide
1074 /// basic functionality.
1075 ///
1076 /// This API is planned to have its functionality finished and then to replace
1077 /// `EmitAssembly` at some point in the future when the default switches.
1078 void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
1079     BackendAction Action, std::unique_ptr<raw_pwrite_stream> OS) {
1080   TimeRegion Region(FrontendTimesIsEnabled ? &CodeGenerationTime : nullptr);
1081   setCommandLineOpts(CodeGenOpts);
1082 
1083   bool RequiresCodeGen = (Action != Backend_EmitNothing &&
1084                           Action != Backend_EmitBC &&
1085                           Action != Backend_EmitLL);
1086   CreateTargetMachine(RequiresCodeGen);
1087 
1088   if (RequiresCodeGen && !TM)
1089     return;
1090   if (TM)
1091     TheModule->setDataLayout(TM->createDataLayout());
1092 
1093   Optional<PGOOptions> PGOOpt;
1094 
1095   if (CodeGenOpts.hasProfileIRInstr())
1096     // -fprofile-generate.
1097     PGOOpt = PGOOptions(CodeGenOpts.InstrProfileOutput.empty()
1098                             ? std::string(DefaultProfileGenName)
1099                             : CodeGenOpts.InstrProfileOutput,
1100                         "", "", PGOOptions::IRInstr, PGOOptions::NoCSAction,
1101                         CodeGenOpts.DebugInfoForProfiling);
1102   else if (CodeGenOpts.hasProfileIRUse()) {
1103     // -fprofile-use.
1104     auto CSAction = CodeGenOpts.hasProfileCSIRUse() ? PGOOptions::CSIRUse
1105                                                     : PGOOptions::NoCSAction;
1106     PGOOpt = PGOOptions(CodeGenOpts.ProfileInstrumentUsePath, "",
1107                         CodeGenOpts.ProfileRemappingFile, PGOOptions::IRUse,
1108                         CSAction, CodeGenOpts.DebugInfoForProfiling);
1109   } else if (!CodeGenOpts.SampleProfileFile.empty())
1110     // -fprofile-sample-use
1111     PGOOpt =
1112         PGOOptions(CodeGenOpts.SampleProfileFile, "",
1113                    CodeGenOpts.ProfileRemappingFile, PGOOptions::SampleUse,
1114                    PGOOptions::NoCSAction, CodeGenOpts.DebugInfoForProfiling);
1115   else if (CodeGenOpts.DebugInfoForProfiling)
1116     // -fdebug-info-for-profiling
1117     PGOOpt = PGOOptions("", "", "", PGOOptions::NoAction,
1118                         PGOOptions::NoCSAction, true);
1119 
1120   // Check to see if we want to generate a CS profile.
1121   if (CodeGenOpts.hasProfileCSIRInstr()) {
1122     assert(!CodeGenOpts.hasProfileCSIRUse() &&
1123            "Cannot have both CSProfileUse pass and CSProfileGen pass at "
1124            "the same time");
1125     if (PGOOpt.hasValue()) {
1126       assert(PGOOpt->Action != PGOOptions::IRInstr &&
1127              PGOOpt->Action != PGOOptions::SampleUse &&
1128              "Cannot run CSProfileGen pass with ProfileGen or SampleUse "
1129              " pass");
1130       PGOOpt->CSProfileGenFile = CodeGenOpts.InstrProfileOutput.empty()
1131                                      ? std::string(DefaultProfileGenName)
1132                                      : CodeGenOpts.InstrProfileOutput;
1133       PGOOpt->CSAction = PGOOptions::CSIRInstr;
1134     } else
1135       PGOOpt = PGOOptions("",
1136                           CodeGenOpts.InstrProfileOutput.empty()
1137                               ? std::string(DefaultProfileGenName)
1138                               : CodeGenOpts.InstrProfileOutput,
1139                           "", PGOOptions::NoAction, PGOOptions::CSIRInstr,
1140                           CodeGenOpts.DebugInfoForProfiling);
1141   }
1142 
1143   PipelineTuningOptions PTO;
1144   PTO.LoopUnrolling = CodeGenOpts.UnrollLoops;
1145   // For historical reasons, loop interleaving is set to mirror setting for loop
1146   // unrolling.
1147   PTO.LoopInterleaving = CodeGenOpts.UnrollLoops;
1148   PTO.LoopVectorization = CodeGenOpts.VectorizeLoop;
1149   PTO.SLPVectorization = CodeGenOpts.VectorizeSLP;
1150   // Only enable CGProfilePass when using integrated assembler, since
1151   // non-integrated assemblers don't recognize .cgprofile section.
1152   PTO.CallGraphProfile = !CodeGenOpts.DisableIntegratedAS;
1153   PTO.Coroutines = LangOpts.Coroutines;
1154 
1155   PassInstrumentationCallbacks PIC;
1156   StandardInstrumentations SI;
1157   SI.registerCallbacks(PIC);
1158   PassBuilder PB(TM.get(), PTO, PGOOpt, &PIC);
1159 
1160   // Attempt to load pass plugins and register their callbacks with PB.
1161   for (auto &PluginFN : CodeGenOpts.PassPlugins) {
1162     auto PassPlugin = PassPlugin::Load(PluginFN);
1163     if (PassPlugin) {
1164       PassPlugin->registerPassBuilderCallbacks(PB);
1165     } else {
1166       Diags.Report(diag::err_fe_unable_to_load_plugin)
1167           << PluginFN << toString(PassPlugin.takeError());
1168     }
1169   }
1170 #define HANDLE_EXTENSION(Ext)                                                  \
1171   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
1172 #include "llvm/Support/Extension.def"
1173 
1174   LoopAnalysisManager LAM(CodeGenOpts.DebugPassManager);
1175   FunctionAnalysisManager FAM(CodeGenOpts.DebugPassManager);
1176   CGSCCAnalysisManager CGAM(CodeGenOpts.DebugPassManager);
1177   ModuleAnalysisManager MAM(CodeGenOpts.DebugPassManager);
1178 
1179   // Register the AA manager first so that our version is the one used.
1180   FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
1181 
1182   // Register the target library analysis directly and give it a customized
1183   // preset TLI.
1184   Triple TargetTriple(TheModule->getTargetTriple());
1185   std::unique_ptr<TargetLibraryInfoImpl> TLII(
1186       createTLII(TargetTriple, CodeGenOpts));
1187   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
1188 
1189   // Register all the basic analyses with the managers.
1190   PB.registerModuleAnalyses(MAM);
1191   PB.registerCGSCCAnalyses(CGAM);
1192   PB.registerFunctionAnalyses(FAM);
1193   PB.registerLoopAnalyses(LAM);
1194   PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
1195 
1196   ModulePassManager MPM(CodeGenOpts.DebugPassManager);
1197 
1198   if (!CodeGenOpts.DisableLLVMPasses) {
1199     bool IsThinLTO = CodeGenOpts.PrepareForThinLTO;
1200     bool IsLTO = CodeGenOpts.PrepareForLTO;
1201 
1202     if (CodeGenOpts.OptimizationLevel == 0) {
1203       // If we reached here with a non-empty index file name, then the index
1204       // file was empty and we are not performing ThinLTO backend compilation
1205       // (used in testing in a distributed build environment). Drop any the type
1206       // test assume sequences inserted for whole program vtables so that
1207       // codegen doesn't complain.
1208       if (!CodeGenOpts.ThinLTOIndexFile.empty())
1209         MPM.addPass(LowerTypeTestsPass(/*ExportSummary=*/nullptr,
1210                                        /*ImportSummary=*/nullptr,
1211                                        /*DropTypeTests=*/true));
1212       if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))
1213         MPM.addPass(GCOVProfilerPass(*Options));
1214       if (Optional<InstrProfOptions> Options =
1215               getInstrProfOptions(CodeGenOpts, LangOpts))
1216         MPM.addPass(InstrProfiling(*Options, false));
1217 
1218       // Build a minimal pipeline based on the semantics required by Clang,
1219       // which is just that always inlining occurs. Further, disable generating
1220       // lifetime intrinsics to avoid enabling further optimizations during
1221       // code generation.
1222       // However, we need to insert lifetime intrinsics to avoid invalid access
1223       // caused by multithreaded coroutines.
1224       MPM.addPass(
1225           AlwaysInlinerPass(/*InsertLifetimeIntrinsics=*/LangOpts.Coroutines));
1226 
1227       // At -O0, we can still do PGO. Add all the requested passes for
1228       // instrumentation PGO, if requested.
1229       if (PGOOpt && (PGOOpt->Action == PGOOptions::IRInstr ||
1230                      PGOOpt->Action == PGOOptions::IRUse))
1231         PB.addPGOInstrPassesForO0(
1232             MPM, CodeGenOpts.DebugPassManager,
1233             /* RunProfileGen */ (PGOOpt->Action == PGOOptions::IRInstr),
1234             /* IsCS */ false, PGOOpt->ProfileFile,
1235             PGOOpt->ProfileRemappingFile);
1236 
1237       // At -O0 we directly run necessary sanitizer passes.
1238       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
1239         MPM.addPass(createModuleToFunctionPassAdaptor(BoundsCheckingPass()));
1240 
1241       // Add UniqueInternalLinkageNames Pass which renames internal linkage
1242       // symbols with unique names.
1243       if (CodeGenOpts.UniqueInternalLinkageNames) {
1244         MPM.addPass(UniqueInternalLinkageNamesPass());
1245       }
1246 
1247       // Lastly, add semantically necessary passes for LTO.
1248       if (IsLTO || IsThinLTO) {
1249         MPM.addPass(CanonicalizeAliasesPass());
1250         MPM.addPass(NameAnonGlobalPass());
1251       }
1252     } else {
1253       // Map our optimization levels into one of the distinct levels used to
1254       // configure the pipeline.
1255       PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);
1256 
1257       // If we reached here with a non-empty index file name, then the index
1258       // file was empty and we are not performing ThinLTO backend compilation
1259       // (used in testing in a distributed build environment). Drop any the type
1260       // test assume sequences inserted for whole program vtables so that
1261       // codegen doesn't complain.
1262       if (!CodeGenOpts.ThinLTOIndexFile.empty())
1263         PB.registerPipelineStartEPCallback([](ModulePassManager &MPM) {
1264           MPM.addPass(LowerTypeTestsPass(/*ExportSummary=*/nullptr,
1265                                          /*ImportSummary=*/nullptr,
1266                                          /*DropTypeTests=*/true));
1267         });
1268 
1269       PB.registerPipelineStartEPCallback([](ModulePassManager &MPM) {
1270         MPM.addPass(createModuleToFunctionPassAdaptor(
1271             EntryExitInstrumenterPass(/*PostInlining=*/false)));
1272       });
1273 
1274       // Register callbacks to schedule sanitizer passes at the appropriate part of
1275       // the pipeline.
1276       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
1277         PB.registerScalarOptimizerLateEPCallback(
1278             [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
1279               FPM.addPass(BoundsCheckingPass());
1280             });
1281 
1282       if (CodeGenOpts.SanitizeCoverageType ||
1283           CodeGenOpts.SanitizeCoverageIndirectCalls ||
1284           CodeGenOpts.SanitizeCoverageTraceCmp) {
1285         PB.registerOptimizerLastEPCallback(
1286             [this](ModulePassManager &MPM,
1287                    PassBuilder::OptimizationLevel Level) {
1288               auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
1289               MPM.addPass(ModuleSanitizerCoveragePass(
1290                   SancovOpts, CodeGenOpts.SanitizeCoverageAllowlistFiles,
1291                   CodeGenOpts.SanitizeCoverageBlocklistFiles));
1292             });
1293       }
1294 
1295       if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
1296         int TrackOrigins = CodeGenOpts.SanitizeMemoryTrackOrigins;
1297         bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::Memory);
1298         PB.registerOptimizerLastEPCallback(
1299             [TrackOrigins, Recover](ModulePassManager &MPM,
1300                                     PassBuilder::OptimizationLevel Level) {
1301               MPM.addPass(MemorySanitizerPass({TrackOrigins, Recover, false}));
1302               MPM.addPass(createModuleToFunctionPassAdaptor(
1303                   MemorySanitizerPass({TrackOrigins, Recover, false})));
1304             });
1305       }
1306       if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
1307         PB.registerOptimizerLastEPCallback(
1308             [](ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
1309               MPM.addPass(ThreadSanitizerPass());
1310               MPM.addPass(
1311                   createModuleToFunctionPassAdaptor(ThreadSanitizerPass()));
1312             });
1313       }
1314       if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
1315         bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::Address);
1316         bool UseAfterScope = CodeGenOpts.SanitizeAddressUseAfterScope;
1317         bool ModuleUseAfterScope = asanUseGlobalsGC(TargetTriple, CodeGenOpts);
1318         bool UseOdrIndicator = CodeGenOpts.SanitizeAddressUseOdrIndicator;
1319         PB.registerOptimizerLastEPCallback(
1320             [Recover, UseAfterScope, ModuleUseAfterScope, UseOdrIndicator](
1321                 ModulePassManager &MPM, PassBuilder::OptimizationLevel Level) {
1322               MPM.addPass(
1323                   RequireAnalysisPass<ASanGlobalsMetadataAnalysis, Module>());
1324               MPM.addPass(ModuleAddressSanitizerPass(
1325                   /*CompileKernel=*/false, Recover, ModuleUseAfterScope,
1326                   UseOdrIndicator));
1327               MPM.addPass(
1328                   createModuleToFunctionPassAdaptor(AddressSanitizerPass(
1329                       /*CompileKernel=*/false, Recover, UseAfterScope)));
1330             });
1331       }
1332       if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))
1333         PB.registerPipelineStartEPCallback([Options](ModulePassManager &MPM) {
1334           MPM.addPass(GCOVProfilerPass(*Options));
1335         });
1336       if (Optional<InstrProfOptions> Options =
1337               getInstrProfOptions(CodeGenOpts, LangOpts))
1338         PB.registerPipelineStartEPCallback([Options](ModulePassManager &MPM) {
1339           MPM.addPass(InstrProfiling(*Options, false));
1340         });
1341 
1342       // Add UniqueInternalLinkageNames Pass which renames internal linkage
1343       // symbols with unique names.
1344       if (CodeGenOpts.UniqueInternalLinkageNames) {
1345         MPM.addPass(UniqueInternalLinkageNamesPass());
1346       }
1347 
1348       if (IsThinLTO) {
1349         MPM = PB.buildThinLTOPreLinkDefaultPipeline(
1350             Level, CodeGenOpts.DebugPassManager);
1351         MPM.addPass(CanonicalizeAliasesPass());
1352         MPM.addPass(NameAnonGlobalPass());
1353       } else if (IsLTO) {
1354         MPM = PB.buildLTOPreLinkDefaultPipeline(Level,
1355                                                 CodeGenOpts.DebugPassManager);
1356         MPM.addPass(CanonicalizeAliasesPass());
1357         MPM.addPass(NameAnonGlobalPass());
1358       } else {
1359         MPM = PB.buildPerModuleDefaultPipeline(Level,
1360                                                CodeGenOpts.DebugPassManager);
1361       }
1362     }
1363 
1364     if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
1365       bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::HWAddress);
1366       MPM.addPass(HWAddressSanitizerPass(
1367           /*CompileKernel=*/false, Recover));
1368     }
1369     if (LangOpts.Sanitize.has(SanitizerKind::KernelHWAddress)) {
1370       MPM.addPass(HWAddressSanitizerPass(
1371           /*CompileKernel=*/true, /*Recover=*/true));
1372     }
1373 
1374     if (CodeGenOpts.OptimizationLevel == 0) {
1375       addCoroutinePassesAtO0(MPM, LangOpts, CodeGenOpts);
1376       addSanitizersAtO0(MPM, TargetTriple, LangOpts, CodeGenOpts);
1377     }
1378   }
1379 
1380   // FIXME: We still use the legacy pass manager to do code generation. We
1381   // create that pass manager here and use it as needed below.
1382   legacy::PassManager CodeGenPasses;
1383   bool NeedCodeGen = false;
1384   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
1385 
1386   // Append any output we need to the pass manager.
1387   switch (Action) {
1388   case Backend_EmitNothing:
1389     break;
1390 
1391   case Backend_EmitBC:
1392     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
1393       if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
1394         ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
1395         if (!ThinLinkOS)
1396           return;
1397       }
1398       TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1399                                CodeGenOpts.EnableSplitLTOUnit);
1400       MPM.addPass(ThinLTOBitcodeWriterPass(*OS, ThinLinkOS ? &ThinLinkOS->os()
1401                                                            : nullptr));
1402     } else {
1403       // Emit a module summary by default for Regular LTO except for ld64
1404       // targets
1405       bool EmitLTOSummary =
1406           (CodeGenOpts.PrepareForLTO &&
1407            !CodeGenOpts.DisableLLVMPasses &&
1408            llvm::Triple(TheModule->getTargetTriple()).getVendor() !=
1409                llvm::Triple::Apple);
1410       if (EmitLTOSummary) {
1411         if (!TheModule->getModuleFlag("ThinLTO"))
1412           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
1413         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1414                                  uint32_t(1));
1415       }
1416       MPM.addPass(
1417           BitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists, EmitLTOSummary));
1418     }
1419     break;
1420 
1421   case Backend_EmitLL:
1422     MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
1423     break;
1424 
1425   case Backend_EmitAssembly:
1426   case Backend_EmitMCNull:
1427   case Backend_EmitObj:
1428     NeedCodeGen = true;
1429     CodeGenPasses.add(
1430         createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
1431     if (!CodeGenOpts.SplitDwarfOutput.empty()) {
1432       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfOutput);
1433       if (!DwoOS)
1434         return;
1435     }
1436     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
1437                        DwoOS ? &DwoOS->os() : nullptr))
1438       // FIXME: Should we handle this error differently?
1439       return;
1440     break;
1441   }
1442 
1443   // Before executing passes, print the final values of the LLVM options.
1444   cl::PrintOptionValues();
1445 
1446   // Now that we have all of the passes ready, run them.
1447   {
1448     PrettyStackTraceString CrashInfo("Optimizer");
1449     MPM.run(*TheModule, MAM);
1450   }
1451 
1452   // Now if needed, run the legacy PM for codegen.
1453   if (NeedCodeGen) {
1454     PrettyStackTraceString CrashInfo("Code generation");
1455     CodeGenPasses.run(*TheModule);
1456   }
1457 
1458   if (ThinLinkOS)
1459     ThinLinkOS->keep();
1460   if (DwoOS)
1461     DwoOS->keep();
1462 }
1463 
1464 Expected<BitcodeModule> clang::FindThinLTOModule(MemoryBufferRef MBRef) {
1465   Expected<std::vector<BitcodeModule>> BMsOrErr = getBitcodeModuleList(MBRef);
1466   if (!BMsOrErr)
1467     return BMsOrErr.takeError();
1468 
1469   // The bitcode file may contain multiple modules, we want the one that is
1470   // marked as being the ThinLTO module.
1471   if (const BitcodeModule *Bm = FindThinLTOModule(*BMsOrErr))
1472     return *Bm;
1473 
1474   return make_error<StringError>("Could not find module summary",
1475                                  inconvertibleErrorCode());
1476 }
1477 
1478 BitcodeModule *clang::FindThinLTOModule(MutableArrayRef<BitcodeModule> BMs) {
1479   for (BitcodeModule &BM : BMs) {
1480     Expected<BitcodeLTOInfo> LTOInfo = BM.getLTOInfo();
1481     if (LTOInfo && LTOInfo->IsThinLTO)
1482       return &BM;
1483   }
1484   return nullptr;
1485 }
1486 
1487 static void runThinLTOBackend(
1488     DiagnosticsEngine &Diags, ModuleSummaryIndex *CombinedIndex, Module *M,
1489     const HeaderSearchOptions &HeaderOpts, const CodeGenOptions &CGOpts,
1490     const clang::TargetOptions &TOpts, const LangOptions &LOpts,
1491     std::unique_ptr<raw_pwrite_stream> OS, std::string SampleProfile,
1492     std::string ProfileRemapping, BackendAction Action) {
1493   StringMap<DenseMap<GlobalValue::GUID, GlobalValueSummary *>>
1494       ModuleToDefinedGVSummaries;
1495   CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
1496 
1497   setCommandLineOpts(CGOpts);
1498 
1499   // We can simply import the values mentioned in the combined index, since
1500   // we should only invoke this using the individual indexes written out
1501   // via a WriteIndexesThinBackend.
1502   FunctionImporter::ImportMapTy ImportList;
1503   for (auto &GlobalList : *CombinedIndex) {
1504     // Ignore entries for undefined references.
1505     if (GlobalList.second.SummaryList.empty())
1506       continue;
1507 
1508     auto GUID = GlobalList.first;
1509     for (auto &Summary : GlobalList.second.SummaryList) {
1510       // Skip the summaries for the importing module. These are included to
1511       // e.g. record required linkage changes.
1512       if (Summary->modulePath() == M->getModuleIdentifier())
1513         continue;
1514       // Add an entry to provoke importing by thinBackend.
1515       ImportList[Summary->modulePath()].insert(GUID);
1516     }
1517   }
1518 
1519   std::vector<std::unique_ptr<llvm::MemoryBuffer>> OwnedImports;
1520   MapVector<llvm::StringRef, llvm::BitcodeModule> ModuleMap;
1521 
1522   for (auto &I : ImportList) {
1523     ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MBOrErr =
1524         llvm::MemoryBuffer::getFile(I.first());
1525     if (!MBOrErr) {
1526       errs() << "Error loading imported file '" << I.first()
1527              << "': " << MBOrErr.getError().message() << "\n";
1528       return;
1529     }
1530 
1531     Expected<BitcodeModule> BMOrErr = FindThinLTOModule(**MBOrErr);
1532     if (!BMOrErr) {
1533       handleAllErrors(BMOrErr.takeError(), [&](ErrorInfoBase &EIB) {
1534         errs() << "Error loading imported file '" << I.first()
1535                << "': " << EIB.message() << '\n';
1536       });
1537       return;
1538     }
1539     ModuleMap.insert({I.first(), *BMOrErr});
1540 
1541     OwnedImports.push_back(std::move(*MBOrErr));
1542   }
1543   auto AddStream = [&](size_t Task) {
1544     return std::make_unique<lto::NativeObjectStream>(std::move(OS));
1545   };
1546   lto::Config Conf;
1547   if (CGOpts.SaveTempsFilePrefix != "") {
1548     if (Error E = Conf.addSaveTemps(CGOpts.SaveTempsFilePrefix + ".",
1549                                     /* UseInputModulePath */ false)) {
1550       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1551         errs() << "Error setting up ThinLTO save-temps: " << EIB.message()
1552                << '\n';
1553       });
1554     }
1555   }
1556   Conf.CPU = TOpts.CPU;
1557   Conf.CodeModel = getCodeModel(CGOpts);
1558   Conf.MAttrs = TOpts.Features;
1559   Conf.RelocModel = CGOpts.RelocationModel;
1560   Conf.CGOptLevel = getCGOptLevel(CGOpts);
1561   Conf.OptLevel = CGOpts.OptimizationLevel;
1562   initTargetOptions(Diags, Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
1563   Conf.SampleProfile = std::move(SampleProfile);
1564   Conf.PTO.LoopUnrolling = CGOpts.UnrollLoops;
1565   // For historical reasons, loop interleaving is set to mirror setting for loop
1566   // unrolling.
1567   Conf.PTO.LoopInterleaving = CGOpts.UnrollLoops;
1568   Conf.PTO.LoopVectorization = CGOpts.VectorizeLoop;
1569   Conf.PTO.SLPVectorization = CGOpts.VectorizeSLP;
1570   // Only enable CGProfilePass when using integrated assembler, since
1571   // non-integrated assemblers don't recognize .cgprofile section.
1572   Conf.PTO.CallGraphProfile = !CGOpts.DisableIntegratedAS;
1573 
1574   // Context sensitive profile.
1575   if (CGOpts.hasProfileCSIRInstr()) {
1576     Conf.RunCSIRInstr = true;
1577     Conf.CSIRProfile = std::move(CGOpts.InstrProfileOutput);
1578   } else if (CGOpts.hasProfileCSIRUse()) {
1579     Conf.RunCSIRInstr = false;
1580     Conf.CSIRProfile = std::move(CGOpts.ProfileInstrumentUsePath);
1581   }
1582 
1583   Conf.ProfileRemapping = std::move(ProfileRemapping);
1584   Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
1585   Conf.DebugPassManager = CGOpts.DebugPassManager;
1586   Conf.RemarksWithHotness = CGOpts.DiagnosticsWithHotness;
1587   Conf.RemarksFilename = CGOpts.OptRecordFile;
1588   Conf.RemarksPasses = CGOpts.OptRecordPasses;
1589   Conf.RemarksFormat = CGOpts.OptRecordFormat;
1590   Conf.SplitDwarfFile = CGOpts.SplitDwarfFile;
1591   Conf.SplitDwarfOutput = CGOpts.SplitDwarfOutput;
1592   switch (Action) {
1593   case Backend_EmitNothing:
1594     Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
1595       return false;
1596     };
1597     break;
1598   case Backend_EmitLL:
1599     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1600       M->print(*OS, nullptr, CGOpts.EmitLLVMUseLists);
1601       return false;
1602     };
1603     break;
1604   case Backend_EmitBC:
1605     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1606       WriteBitcodeToFile(*M, *OS, CGOpts.EmitLLVMUseLists);
1607       return false;
1608     };
1609     break;
1610   default:
1611     Conf.CGFileType = getCodeGenFileType(Action);
1612     break;
1613   }
1614   if (Error E = thinBackend(
1615           Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
1616           ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
1617     handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1618       errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
1619     });
1620   }
1621 }
1622 
1623 void clang::EmitBackendOutput(DiagnosticsEngine &Diags,
1624                               const HeaderSearchOptions &HeaderOpts,
1625                               const CodeGenOptions &CGOpts,
1626                               const clang::TargetOptions &TOpts,
1627                               const LangOptions &LOpts,
1628                               const llvm::DataLayout &TDesc, Module *M,
1629                               BackendAction Action,
1630                               std::unique_ptr<raw_pwrite_stream> OS) {
1631 
1632   llvm::TimeTraceScope TimeScope("Backend");
1633 
1634   std::unique_ptr<llvm::Module> EmptyModule;
1635   if (!CGOpts.ThinLTOIndexFile.empty()) {
1636     // If we are performing a ThinLTO importing compile, load the function index
1637     // into memory and pass it into runThinLTOBackend, which will run the
1638     // function importer and invoke LTO passes.
1639     Expected<std::unique_ptr<ModuleSummaryIndex>> IndexOrErr =
1640         llvm::getModuleSummaryIndexForFile(CGOpts.ThinLTOIndexFile,
1641                                            /*IgnoreEmptyThinLTOIndexFile*/true);
1642     if (!IndexOrErr) {
1643       logAllUnhandledErrors(IndexOrErr.takeError(), errs(),
1644                             "Error loading index file '" +
1645                             CGOpts.ThinLTOIndexFile + "': ");
1646       return;
1647     }
1648     std::unique_ptr<ModuleSummaryIndex> CombinedIndex = std::move(*IndexOrErr);
1649     // A null CombinedIndex means we should skip ThinLTO compilation
1650     // (LLVM will optionally ignore empty index files, returning null instead
1651     // of an error).
1652     if (CombinedIndex) {
1653       if (!CombinedIndex->skipModuleByDistributedBackend()) {
1654         runThinLTOBackend(Diags, CombinedIndex.get(), M, HeaderOpts, CGOpts,
1655                           TOpts, LOpts, std::move(OS), CGOpts.SampleProfileFile,
1656                           CGOpts.ProfileRemappingFile, Action);
1657         return;
1658       }
1659       // Distributed indexing detected that nothing from the module is needed
1660       // for the final linking. So we can skip the compilation. We sill need to
1661       // output an empty object file to make sure that a linker does not fail
1662       // trying to read it. Also for some features, like CFI, we must skip
1663       // the compilation as CombinedIndex does not contain all required
1664       // information.
1665       EmptyModule = std::make_unique<llvm::Module>("empty", M->getContext());
1666       EmptyModule->setTargetTriple(M->getTargetTriple());
1667       M = EmptyModule.get();
1668     }
1669   }
1670 
1671   EmitAssemblyHelper AsmHelper(Diags, HeaderOpts, CGOpts, TOpts, LOpts, M);
1672 
1673   if (CGOpts.ExperimentalNewPassManager)
1674     AsmHelper.EmitAssemblyWithNewPassManager(Action, std::move(OS));
1675   else
1676     AsmHelper.EmitAssembly(Action, std::move(OS));
1677 
1678   // Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
1679   // DataLayout.
1680   if (AsmHelper.TM) {
1681     std::string DLDesc = M->getDataLayout().getStringRepresentation();
1682     if (DLDesc != TDesc.getStringRepresentation()) {
1683       unsigned DiagID = Diags.getCustomDiagID(
1684           DiagnosticsEngine::Error, "backend data layout '%0' does not match "
1685                                     "expected target description '%1'");
1686       Diags.Report(DiagID) << DLDesc << TDesc.getStringRepresentation();
1687     }
1688   }
1689 }
1690 
1691 // With -fembed-bitcode, save a copy of the llvm IR as data in the
1692 // __LLVM,__bitcode section.
1693 void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
1694                          llvm::MemoryBufferRef Buf) {
1695   if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
1696     return;
1697   llvm::EmbedBitcodeInModule(
1698       *M, Buf, CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker,
1699       CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode,
1700       &CGOpts.CmdArgs);
1701 }
1702