1 //===- Parsing, selection, and construction of pass pipelines -------------===//
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 /// \file
9 ///
10 /// This file provides the implementation of the PassBuilder based on our
11 /// static pass registry as well as related functionality. It also provides
12 /// helpers to aid in analyzing, debugging, and testing passes and pass
13 /// pipelines.
14 ///
15 //===----------------------------------------------------------------------===//
16 
17 #include "llvm/Passes/PassBuilder.h"
18 #include "llvm/ADT/StringSwitch.h"
19 #include "llvm/Analysis/AliasAnalysis.h"
20 #include "llvm/Analysis/AliasAnalysisEvaluator.h"
21 #include "llvm/Analysis/AssumptionCache.h"
22 #include "llvm/Analysis/BasicAliasAnalysis.h"
23 #include "llvm/Analysis/BlockFrequencyInfo.h"
24 #include "llvm/Analysis/BranchProbabilityInfo.h"
25 #include "llvm/Analysis/CFGPrinter.h"
26 #include "llvm/Analysis/CFLAndersAliasAnalysis.h"
27 #include "llvm/Analysis/CFLSteensAliasAnalysis.h"
28 #include "llvm/Analysis/CGSCCPassManager.h"
29 #include "llvm/Analysis/CallGraph.h"
30 #include "llvm/Analysis/DDG.h"
31 #include "llvm/Analysis/DemandedBits.h"
32 #include "llvm/Analysis/DependenceAnalysis.h"
33 #include "llvm/Analysis/DominanceFrontier.h"
34 #include "llvm/Analysis/GlobalsModRef.h"
35 #include "llvm/Analysis/IVUsers.h"
36 #include "llvm/Analysis/LazyCallGraph.h"
37 #include "llvm/Analysis/LazyValueInfo.h"
38 #include "llvm/Analysis/LoopAccessAnalysis.h"
39 #include "llvm/Analysis/LoopCacheAnalysis.h"
40 #include "llvm/Analysis/LoopInfo.h"
41 #include "llvm/Analysis/LoopNestAnalysis.h"
42 #include "llvm/Analysis/MemoryDependenceAnalysis.h"
43 #include "llvm/Analysis/MemorySSA.h"
44 #include "llvm/Analysis/ModuleSummaryAnalysis.h"
45 #include "llvm/Analysis/OptimizationRemarkEmitter.h"
46 #include "llvm/Analysis/PhiValues.h"
47 #include "llvm/Analysis/PostDominators.h"
48 #include "llvm/Analysis/ProfileSummaryInfo.h"
49 #include "llvm/Analysis/RegionInfo.h"
50 #include "llvm/Analysis/ScalarEvolution.h"
51 #include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
52 #include "llvm/Analysis/ScopedNoAliasAA.h"
53 #include "llvm/Analysis/StackSafetyAnalysis.h"
54 #include "llvm/Analysis/TargetLibraryInfo.h"
55 #include "llvm/Analysis/TargetTransformInfo.h"
56 #include "llvm/Analysis/TypeBasedAliasAnalysis.h"
57 #include "llvm/CodeGen/MachineModuleInfo.h"
58 #include "llvm/CodeGen/PreISelIntrinsicLowering.h"
59 #include "llvm/CodeGen/UnreachableBlockElim.h"
60 #include "llvm/IR/Dominators.h"
61 #include "llvm/IR/IRPrintingPasses.h"
62 #include "llvm/IR/KnowledgeRetention.h"
63 #include "llvm/IR/PassManager.h"
64 #include "llvm/IR/SafepointIRVerifier.h"
65 #include "llvm/IR/Verifier.h"
66 #include "llvm/Support/CommandLine.h"
67 #include "llvm/Support/Debug.h"
68 #include "llvm/Support/FormatVariadic.h"
69 #include "llvm/Support/Regex.h"
70 #include "llvm/Target/TargetMachine.h"
71 #include "llvm/Transforms/AggressiveInstCombine/AggressiveInstCombine.h"
72 #include "llvm/Transforms/Coroutines/CoroCleanup.h"
73 #include "llvm/Transforms/Coroutines/CoroEarly.h"
74 #include "llvm/Transforms/Coroutines/CoroElide.h"
75 #include "llvm/Transforms/Coroutines/CoroSplit.h"
76 #include "llvm/Transforms/IPO/AlwaysInliner.h"
77 #include "llvm/Transforms/IPO/ArgumentPromotion.h"
78 #include "llvm/Transforms/IPO/Attributor.h"
79 #include "llvm/Transforms/IPO/CalledValuePropagation.h"
80 #include "llvm/Transforms/IPO/ConstantMerge.h"
81 #include "llvm/Transforms/IPO/CrossDSOCFI.h"
82 #include "llvm/Transforms/IPO/DeadArgumentElimination.h"
83 #include "llvm/Transforms/IPO/ElimAvailExtern.h"
84 #include "llvm/Transforms/IPO/ForceFunctionAttrs.h"
85 #include "llvm/Transforms/IPO/FunctionAttrs.h"
86 #include "llvm/Transforms/IPO/FunctionImport.h"
87 #include "llvm/Transforms/IPO/GlobalDCE.h"
88 #include "llvm/Transforms/IPO/GlobalOpt.h"
89 #include "llvm/Transforms/IPO/GlobalSplit.h"
90 #include "llvm/Transforms/IPO/HotColdSplitting.h"
91 #include "llvm/Transforms/IPO/InferFunctionAttrs.h"
92 #include "llvm/Transforms/IPO/Inliner.h"
93 #include "llvm/Transforms/IPO/Internalize.h"
94 #include "llvm/Transforms/IPO/LowerTypeTests.h"
95 #include "llvm/Transforms/IPO/MergeFunctions.h"
96 #include "llvm/Transforms/IPO/OpenMPOpt.h"
97 #include "llvm/Transforms/IPO/PartialInlining.h"
98 #include "llvm/Transforms/IPO/SCCP.h"
99 #include "llvm/Transforms/IPO/SampleProfile.h"
100 #include "llvm/Transforms/IPO/StripDeadPrototypes.h"
101 #include "llvm/Transforms/IPO/SyntheticCountsPropagation.h"
102 #include "llvm/Transforms/IPO/WholeProgramDevirt.h"
103 #include "llvm/Transforms/InstCombine/InstCombine.h"
104 #include "llvm/Transforms/Instrumentation.h"
105 #include "llvm/Transforms/Instrumentation/AddressSanitizer.h"
106 #include "llvm/Transforms/Instrumentation/BoundsChecking.h"
107 #include "llvm/Transforms/Instrumentation/CGProfile.h"
108 #include "llvm/Transforms/Instrumentation/ControlHeightReduction.h"
109 #include "llvm/Transforms/Instrumentation/GCOVProfiler.h"
110 #include "llvm/Transforms/Instrumentation/HWAddressSanitizer.h"
111 #include "llvm/Transforms/Instrumentation/InstrOrderFile.h"
112 #include "llvm/Transforms/Instrumentation/InstrProfiling.h"
113 #include "llvm/Transforms/Instrumentation/MemorySanitizer.h"
114 #include "llvm/Transforms/Instrumentation/PGOInstrumentation.h"
115 #include "llvm/Transforms/Instrumentation/PoisonChecking.h"
116 #include "llvm/Transforms/Instrumentation/SanitizerCoverage.h"
117 #include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
118 #include "llvm/Transforms/Scalar/ADCE.h"
119 #include "llvm/Transforms/Scalar/AlignmentFromAssumptions.h"
120 #include "llvm/Transforms/Scalar/BDCE.h"
121 #include "llvm/Transforms/Scalar/CallSiteSplitting.h"
122 #include "llvm/Transforms/Scalar/ConstantHoisting.h"
123 #include "llvm/Transforms/Scalar/CorrelatedValuePropagation.h"
124 #include "llvm/Transforms/Scalar/DCE.h"
125 #include "llvm/Transforms/Scalar/DeadStoreElimination.h"
126 #include "llvm/Transforms/Scalar/DivRemPairs.h"
127 #include "llvm/Transforms/Scalar/EarlyCSE.h"
128 #include "llvm/Transforms/Scalar/Float2Int.h"
129 #include "llvm/Transforms/Scalar/GVN.h"
130 #include "llvm/Transforms/Scalar/GuardWidening.h"
131 #include "llvm/Transforms/Scalar/IVUsersPrinter.h"
132 #include "llvm/Transforms/Scalar/IndVarSimplify.h"
133 #include "llvm/Transforms/Scalar/InductiveRangeCheckElimination.h"
134 #include "llvm/Transforms/Scalar/InstSimplifyPass.h"
135 #include "llvm/Transforms/Scalar/JumpThreading.h"
136 #include "llvm/Transforms/Scalar/LICM.h"
137 #include "llvm/Transforms/Scalar/LoopAccessAnalysisPrinter.h"
138 #include "llvm/Transforms/Scalar/LoopDataPrefetch.h"
139 #include "llvm/Transforms/Scalar/LoopDeletion.h"
140 #include "llvm/Transforms/Scalar/LoopDistribute.h"
141 #include "llvm/Transforms/Scalar/LoopFuse.h"
142 #include "llvm/Transforms/Scalar/LoopIdiomRecognize.h"
143 #include "llvm/Transforms/Scalar/LoopInstSimplify.h"
144 #include "llvm/Transforms/Scalar/LoopLoadElimination.h"
145 #include "llvm/Transforms/Scalar/LoopPassManager.h"
146 #include "llvm/Transforms/Scalar/LoopPredication.h"
147 #include "llvm/Transforms/Scalar/LoopRotation.h"
148 #include "llvm/Transforms/Scalar/LoopSimplifyCFG.h"
149 #include "llvm/Transforms/Scalar/LoopSink.h"
150 #include "llvm/Transforms/Scalar/LoopStrengthReduce.h"
151 #include "llvm/Transforms/Scalar/LoopUnrollAndJamPass.h"
152 #include "llvm/Transforms/Scalar/LoopUnrollPass.h"
153 #include "llvm/Transforms/Scalar/LowerAtomic.h"
154 #include "llvm/Transforms/Scalar/LowerConstantIntrinsics.h"
155 #include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h"
156 #include "llvm/Transforms/Scalar/LowerGuardIntrinsic.h"
157 #include "llvm/Transforms/Scalar/LowerMatrixIntrinsics.h"
158 #include "llvm/Transforms/Scalar/LowerWidenableCondition.h"
159 #include "llvm/Transforms/Scalar/MakeGuardsExplicit.h"
160 #include "llvm/Transforms/Scalar/MemCpyOptimizer.h"
161 #include "llvm/Transforms/Scalar/MergeICmps.h"
162 #include "llvm/Transforms/Scalar/MergedLoadStoreMotion.h"
163 #include "llvm/Transforms/Scalar/NaryReassociate.h"
164 #include "llvm/Transforms/Scalar/NewGVN.h"
165 #include "llvm/Transforms/Scalar/PartiallyInlineLibCalls.h"
166 #include "llvm/Transforms/Scalar/Reassociate.h"
167 #include "llvm/Transforms/Scalar/RewriteStatepointsForGC.h"
168 #include "llvm/Transforms/Scalar/SCCP.h"
169 #include "llvm/Transforms/Scalar/SROA.h"
170 #include "llvm/Transforms/Scalar/Scalarizer.h"
171 #include "llvm/Transforms/Scalar/SimpleLoopUnswitch.h"
172 #include "llvm/Transforms/Scalar/SimplifyCFG.h"
173 #include "llvm/Transforms/Scalar/Sink.h"
174 #include "llvm/Transforms/Scalar/SpeculateAroundPHIs.h"
175 #include "llvm/Transforms/Scalar/SpeculativeExecution.h"
176 #include "llvm/Transforms/Scalar/TailRecursionElimination.h"
177 #include "llvm/Transforms/Scalar/WarnMissedTransforms.h"
178 #include "llvm/Transforms/Utils/AddDiscriminators.h"
179 #include "llvm/Transforms/Utils/BreakCriticalEdges.h"
180 #include "llvm/Transforms/Utils/CanonicalizeAliases.h"
181 #include "llvm/Transforms/Utils/EntryExitInstrumenter.h"
182 #include "llvm/Transforms/Utils/InjectTLIMappings.h"
183 #include "llvm/Transforms/Utils/LCSSA.h"
184 #include "llvm/Transforms/Utils/LibCallsShrinkWrap.h"
185 #include "llvm/Transforms/Utils/LoopSimplify.h"
186 #include "llvm/Transforms/Utils/LowerInvoke.h"
187 #include "llvm/Transforms/Utils/Mem2Reg.h"
188 #include "llvm/Transforms/Utils/NameAnonGlobals.h"
189 #include "llvm/Transforms/Utils/SymbolRewriter.h"
190 #include "llvm/Transforms/Vectorize/LoadStoreVectorizer.h"
191 #include "llvm/Transforms/Vectorize/LoopVectorize.h"
192 #include "llvm/Transforms/Vectorize/SLPVectorizer.h"
193 #include "llvm/Transforms/Vectorize/VectorCombine.h"
194 
195 using namespace llvm;
196 
197 static cl::opt<unsigned> MaxDevirtIterations("pm-max-devirt-iterations",
198                                              cl::ReallyHidden, cl::init(4));
199 static cl::opt<bool>
200     RunPartialInlining("enable-npm-partial-inlining", cl::init(false),
201                        cl::Hidden, cl::ZeroOrMore,
202                        cl::desc("Run Partial inlinining pass"));
203 
204 static cl::opt<int> PreInlineThreshold(
205     "npm-preinline-threshold", cl::Hidden, cl::init(75), cl::ZeroOrMore,
206     cl::desc("Control the amount of inlining in pre-instrumentation inliner "
207              "(default = 75)"));
208 
209 static cl::opt<bool>
210     RunNewGVN("enable-npm-newgvn", cl::init(false),
211               cl::Hidden, cl::ZeroOrMore,
212               cl::desc("Run NewGVN instead of GVN"));
213 
214 static cl::opt<bool> EnableGVNHoist(
215     "enable-npm-gvn-hoist", cl::init(false), cl::Hidden,
216     cl::desc("Enable the GVN hoisting pass for the new PM (default = off)"));
217 
218 static cl::opt<bool> EnableGVNSink(
219     "enable-npm-gvn-sink", cl::init(false), cl::Hidden,
220     cl::desc("Enable the GVN hoisting pass for the new PM (default = off)"));
221 
222 static cl::opt<bool> EnableUnrollAndJam(
223     "enable-npm-unroll-and-jam", cl::init(false), cl::Hidden,
224     cl::desc("Enable the Unroll and Jam pass for the new PM (default = off)"));
225 
226 static cl::opt<bool> EnableSyntheticCounts(
227     "enable-npm-synthetic-counts", cl::init(false), cl::Hidden, cl::ZeroOrMore,
228     cl::desc("Run synthetic function entry count generation "
229              "pass"));
230 
231 static const Regex DefaultAliasRegex(
232     "^(default|thinlto-pre-link|thinlto|lto-pre-link|lto)<(O[0123sz])>$");
233 
234 // This option is used in simplifying testing SampleFDO optimizations for
235 // profile loading.
236 static cl::opt<bool>
237     EnableCHR("enable-chr-npm", cl::init(true), cl::Hidden,
238               cl::desc("Enable control height reduction optimization (CHR)"));
239 
240 PipelineTuningOptions::PipelineTuningOptions() {
241   LoopInterleaving = EnableLoopInterleaving;
242   LoopVectorization = EnableLoopVectorization;
243   SLPVectorization = RunSLPVectorization;
244   LoopUnrolling = true;
245   ForgetAllSCEVInLoopUnroll = ForgetSCEVInLoopUnroll;
246   Coroutines = false;
247   LicmMssaOptCap = SetLicmMssaOptCap;
248   LicmMssaNoAccForPromotionCap = SetLicmMssaNoAccForPromotionCap;
249 }
250 
251 extern cl::opt<bool> EnableHotColdSplit;
252 extern cl::opt<bool> EnableOrderFileInstrumentation;
253 
254 extern cl::opt<bool> FlattenedProfileUsed;
255 
256 const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O0 = {
257     /*SpeedLevel*/ 0,
258     /*SizeLevel*/ 0};
259 const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O1 = {
260     /*SpeedLevel*/ 1,
261     /*SizeLevel*/ 0};
262 const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O2 = {
263     /*SpeedLevel*/ 2,
264     /*SizeLevel*/ 0};
265 const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::O3 = {
266     /*SpeedLevel*/ 3,
267     /*SizeLevel*/ 0};
268 const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::Os = {
269     /*SpeedLevel*/ 2,
270     /*SizeLevel*/ 1};
271 const PassBuilder::OptimizationLevel PassBuilder::OptimizationLevel::Oz = {
272     /*SpeedLevel*/ 2,
273     /*SizeLevel*/ 2};
274 
275 namespace {
276 
277 /// No-op module pass which does nothing.
278 struct NoOpModulePass {
279   PreservedAnalyses run(Module &M, ModuleAnalysisManager &) {
280     return PreservedAnalyses::all();
281   }
282   static StringRef name() { return "NoOpModulePass"; }
283 };
284 
285 /// No-op module analysis.
286 class NoOpModuleAnalysis : public AnalysisInfoMixin<NoOpModuleAnalysis> {
287   friend AnalysisInfoMixin<NoOpModuleAnalysis>;
288   static AnalysisKey Key;
289 
290 public:
291   struct Result {};
292   Result run(Module &, ModuleAnalysisManager &) { return Result(); }
293   static StringRef name() { return "NoOpModuleAnalysis"; }
294 };
295 
296 /// No-op CGSCC pass which does nothing.
297 struct NoOpCGSCCPass {
298   PreservedAnalyses run(LazyCallGraph::SCC &C, CGSCCAnalysisManager &,
299                         LazyCallGraph &, CGSCCUpdateResult &UR) {
300     return PreservedAnalyses::all();
301   }
302   static StringRef name() { return "NoOpCGSCCPass"; }
303 };
304 
305 /// No-op CGSCC analysis.
306 class NoOpCGSCCAnalysis : public AnalysisInfoMixin<NoOpCGSCCAnalysis> {
307   friend AnalysisInfoMixin<NoOpCGSCCAnalysis>;
308   static AnalysisKey Key;
309 
310 public:
311   struct Result {};
312   Result run(LazyCallGraph::SCC &, CGSCCAnalysisManager &, LazyCallGraph &G) {
313     return Result();
314   }
315   static StringRef name() { return "NoOpCGSCCAnalysis"; }
316 };
317 
318 /// No-op function pass which does nothing.
319 struct NoOpFunctionPass {
320   PreservedAnalyses run(Function &F, FunctionAnalysisManager &) {
321     return PreservedAnalyses::all();
322   }
323   static StringRef name() { return "NoOpFunctionPass"; }
324 };
325 
326 /// No-op function analysis.
327 class NoOpFunctionAnalysis : public AnalysisInfoMixin<NoOpFunctionAnalysis> {
328   friend AnalysisInfoMixin<NoOpFunctionAnalysis>;
329   static AnalysisKey Key;
330 
331 public:
332   struct Result {};
333   Result run(Function &, FunctionAnalysisManager &) { return Result(); }
334   static StringRef name() { return "NoOpFunctionAnalysis"; }
335 };
336 
337 /// No-op loop pass which does nothing.
338 struct NoOpLoopPass {
339   PreservedAnalyses run(Loop &L, LoopAnalysisManager &,
340                         LoopStandardAnalysisResults &, LPMUpdater &) {
341     return PreservedAnalyses::all();
342   }
343   static StringRef name() { return "NoOpLoopPass"; }
344 };
345 
346 /// No-op loop analysis.
347 class NoOpLoopAnalysis : public AnalysisInfoMixin<NoOpLoopAnalysis> {
348   friend AnalysisInfoMixin<NoOpLoopAnalysis>;
349   static AnalysisKey Key;
350 
351 public:
352   struct Result {};
353   Result run(Loop &, LoopAnalysisManager &, LoopStandardAnalysisResults &) {
354     return Result();
355   }
356   static StringRef name() { return "NoOpLoopAnalysis"; }
357 };
358 
359 AnalysisKey NoOpModuleAnalysis::Key;
360 AnalysisKey NoOpCGSCCAnalysis::Key;
361 AnalysisKey NoOpFunctionAnalysis::Key;
362 AnalysisKey NoOpLoopAnalysis::Key;
363 
364 } // End anonymous namespace.
365 
366 void PassBuilder::invokePeepholeEPCallbacks(
367     FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
368   for (auto &C : PeepholeEPCallbacks)
369     C(FPM, Level);
370 }
371 
372 void PassBuilder::registerModuleAnalyses(ModuleAnalysisManager &MAM) {
373 #define MODULE_ANALYSIS(NAME, CREATE_PASS)                                     \
374   MAM.registerPass([&] { return CREATE_PASS; });
375 #include "PassRegistry.def"
376 
377   for (auto &C : ModuleAnalysisRegistrationCallbacks)
378     C(MAM);
379 }
380 
381 void PassBuilder::registerCGSCCAnalyses(CGSCCAnalysisManager &CGAM) {
382 #define CGSCC_ANALYSIS(NAME, CREATE_PASS)                                      \
383   CGAM.registerPass([&] { return CREATE_PASS; });
384 #include "PassRegistry.def"
385 
386   for (auto &C : CGSCCAnalysisRegistrationCallbacks)
387     C(CGAM);
388 }
389 
390 void PassBuilder::registerFunctionAnalyses(FunctionAnalysisManager &FAM) {
391 #define FUNCTION_ANALYSIS(NAME, CREATE_PASS)                                   \
392   FAM.registerPass([&] { return CREATE_PASS; });
393 #include "PassRegistry.def"
394 
395   for (auto &C : FunctionAnalysisRegistrationCallbacks)
396     C(FAM);
397 }
398 
399 void PassBuilder::registerLoopAnalyses(LoopAnalysisManager &LAM) {
400 #define LOOP_ANALYSIS(NAME, CREATE_PASS)                                       \
401   LAM.registerPass([&] { return CREATE_PASS; });
402 #include "PassRegistry.def"
403 
404   for (auto &C : LoopAnalysisRegistrationCallbacks)
405     C(LAM);
406 }
407 
408 FunctionPassManager
409 PassBuilder::buildFunctionSimplificationPipeline(OptimizationLevel Level,
410                                                  ThinLTOPhase Phase,
411                                                  bool DebugLogging) {
412   assert(Level != OptimizationLevel::O0 && "Must request optimizations!");
413   FunctionPassManager FPM(DebugLogging);
414 
415   // Form SSA out of local memory accesses after breaking apart aggregates into
416   // scalars.
417   FPM.addPass(SROA());
418 
419   // Catch trivial redundancies
420   FPM.addPass(EarlyCSEPass(true /* Enable mem-ssa. */));
421 
422   // Hoisting of scalars and load expressions.
423   if (Level.getSpeedupLevel() > 1) {
424     if (EnableGVNHoist)
425       FPM.addPass(GVNHoistPass());
426 
427     // Global value numbering based sinking.
428     if (EnableGVNSink) {
429       FPM.addPass(GVNSinkPass());
430       FPM.addPass(SimplifyCFGPass());
431     }
432   }
433 
434   // Speculative execution if the target has divergent branches; otherwise nop.
435   if (Level.getSpeedupLevel() > 1) {
436     FPM.addPass(SpeculativeExecutionPass());
437 
438     // Optimize based on known information about branches, and cleanup afterward.
439     FPM.addPass(JumpThreadingPass());
440     FPM.addPass(CorrelatedValuePropagationPass());
441   }
442   FPM.addPass(SimplifyCFGPass());
443   if (Level == OptimizationLevel::O3)
444     FPM.addPass(AggressiveInstCombinePass());
445   FPM.addPass(InstCombinePass());
446 
447   if (!Level.isOptimizingForSize())
448     FPM.addPass(LibCallsShrinkWrapPass());
449 
450   invokePeepholeEPCallbacks(FPM, Level);
451 
452   // For PGO use pipeline, try to optimize memory intrinsics such as memcpy
453   // using the size value profile. Don't perform this when optimizing for size.
454   if (PGOOpt && PGOOpt->Action == PGOOptions::IRUse &&
455       (Level.getSpeedupLevel() > 1 && !Level.isOptimizingForSize()))
456     FPM.addPass(PGOMemOPSizeOpt());
457 
458   // TODO: Investigate the cost/benefit of tail call elimination on debugging.
459   if (Level.getSpeedupLevel() > 1)
460     FPM.addPass(TailCallElimPass());
461   FPM.addPass(SimplifyCFGPass());
462 
463   // Form canonically associated expression trees, and simplify the trees using
464   // basic mathematical properties. For example, this will form (nearly)
465   // minimal multiplication trees.
466   FPM.addPass(ReassociatePass());
467 
468   // Add the primary loop simplification pipeline.
469   // FIXME: Currently this is split into two loop pass pipelines because we run
470   // some function passes in between them. These can and should be removed
471   // and/or replaced by scheduling the loop pass equivalents in the correct
472   // positions. But those equivalent passes aren't powerful enough yet.
473   // Specifically, `SimplifyCFGPass` and `InstCombinePass` are currently still
474   // used. We have `LoopSimplifyCFGPass` which isn't yet powerful enough yet to
475   // fully replace `SimplifyCFGPass`, and the closest to the other we have is
476   // `LoopInstSimplify`.
477   LoopPassManager LPM1(DebugLogging), LPM2(DebugLogging);
478 
479   // Simplify the loop body. We do this initially to clean up after other loop
480   // passes run, either when iterating on a loop or on inner loops with
481   // implications on the outer loop.
482   LPM1.addPass(LoopInstSimplifyPass());
483   LPM1.addPass(LoopSimplifyCFGPass());
484 
485   // Rotate Loop - disable header duplication at -Oz
486   LPM1.addPass(LoopRotatePass(Level != OptimizationLevel::Oz));
487   // TODO: Investigate promotion cap for O1.
488   LPM1.addPass(LICMPass(PTO.LicmMssaOptCap, PTO.LicmMssaNoAccForPromotionCap));
489   LPM1.addPass(SimpleLoopUnswitchPass());
490   LPM2.addPass(IndVarSimplifyPass());
491   LPM2.addPass(LoopIdiomRecognizePass());
492 
493   for (auto &C : LateLoopOptimizationsEPCallbacks)
494     C(LPM2, Level);
495 
496   LPM2.addPass(LoopDeletionPass());
497   // Do not enable unrolling in PreLinkThinLTO phase during sample PGO
498   // because it changes IR to makes profile annotation in back compile
499   // inaccurate.
500   if ((Phase != ThinLTOPhase::PreLink || !PGOOpt ||
501        PGOOpt->Action != PGOOptions::SampleUse) &&
502       PTO.LoopUnrolling)
503     LPM2.addPass(LoopFullUnrollPass(Level.getSpeedupLevel(),
504                                     /*OnlyWhenForced=*/false,
505                                     PTO.ForgetAllSCEVInLoopUnroll));
506 
507   for (auto &C : LoopOptimizerEndEPCallbacks)
508     C(LPM2, Level);
509 
510   // We provide the opt remark emitter pass for LICM to use. We only need to do
511   // this once as it is immutable.
512   FPM.addPass(RequireAnalysisPass<OptimizationRemarkEmitterAnalysis, Function>());
513   FPM.addPass(createFunctionToLoopPassAdaptor(
514       std::move(LPM1), EnableMSSALoopDependency, DebugLogging));
515   FPM.addPass(SimplifyCFGPass());
516   FPM.addPass(InstCombinePass());
517   // The loop passes in LPM2 (IndVarSimplifyPass, LoopIdiomRecognizePass,
518   // LoopDeletionPass and LoopFullUnrollPass) do not preserve MemorySSA.
519   // *All* loop passes must preserve it, in order to be able to use it.
520   FPM.addPass(createFunctionToLoopPassAdaptor(
521       std::move(LPM2), /*UseMemorySSA=*/false, DebugLogging));
522 
523   // Delete small array after loop unroll.
524   FPM.addPass(SROA());
525 
526   // Eliminate redundancies.
527   if (Level != OptimizationLevel::O1) {
528     // These passes add substantial compile time so skip them at O1.
529     FPM.addPass(MergedLoadStoreMotionPass());
530     if (RunNewGVN)
531       FPM.addPass(NewGVNPass());
532     else
533       FPM.addPass(GVN());
534   }
535 
536   // Specially optimize memory movement as it doesn't look like dataflow in SSA.
537   FPM.addPass(MemCpyOptPass());
538 
539   // Sparse conditional constant propagation.
540   // FIXME: It isn't clear why we do this *after* loop passes rather than
541   // before...
542   FPM.addPass(SCCPPass());
543 
544   // Delete dead bit computations (instcombine runs after to fold away the dead
545   // computations, and then ADCE will run later to exploit any new DCE
546   // opportunities that creates).
547   FPM.addPass(BDCEPass());
548 
549   // Run instcombine after redundancy and dead bit elimination to exploit
550   // opportunities opened up by them.
551   FPM.addPass(InstCombinePass());
552   invokePeepholeEPCallbacks(FPM, Level);
553 
554   // Re-consider control flow based optimizations after redundancy elimination,
555   // redo DCE, etc.
556   if (Level.getSpeedupLevel() > 1) {
557     FPM.addPass(JumpThreadingPass());
558     FPM.addPass(CorrelatedValuePropagationPass());
559     FPM.addPass(DSEPass());
560     FPM.addPass(createFunctionToLoopPassAdaptor(
561         LICMPass(PTO.LicmMssaOptCap, PTO.LicmMssaNoAccForPromotionCap),
562         EnableMSSALoopDependency, DebugLogging));
563   }
564 
565   if (PTO.Coroutines)
566     FPM.addPass(CoroElidePass());
567 
568   for (auto &C : ScalarOptimizerLateEPCallbacks)
569     C(FPM, Level);
570 
571   // Finally, do an expensive DCE pass to catch all the dead code exposed by
572   // the simplifications and basic cleanup after all the simplifications.
573   // TODO: Investigate if this is too expensive.
574   FPM.addPass(ADCEPass());
575   FPM.addPass(SimplifyCFGPass());
576   FPM.addPass(InstCombinePass());
577   invokePeepholeEPCallbacks(FPM, Level);
578 
579   if (EnableCHR && Level == OptimizationLevel::O3 && PGOOpt &&
580       (PGOOpt->Action == PGOOptions::IRUse ||
581        PGOOpt->Action == PGOOptions::SampleUse))
582     FPM.addPass(ControlHeightReductionPass());
583 
584   return FPM;
585 }
586 
587 void PassBuilder::addPGOInstrPasses(ModulePassManager &MPM, bool DebugLogging,
588                                     PassBuilder::OptimizationLevel Level,
589                                     bool RunProfileGen, bool IsCS,
590                                     std::string ProfileFile,
591                                     std::string ProfileRemappingFile) {
592   assert(Level != OptimizationLevel::O0 && "Not expecting O0 here!");
593   // Generally running simplification passes and the inliner with an high
594   // threshold results in smaller executables, but there may be cases where
595   // the size grows, so let's be conservative here and skip this simplification
596   // at -Os/Oz. We will not do this  inline for context sensistive PGO (when
597   // IsCS is true).
598   if (!Level.isOptimizingForSize() && !IsCS) {
599     InlineParams IP;
600 
601     IP.DefaultThreshold = PreInlineThreshold;
602 
603     // FIXME: The hint threshold has the same value used by the regular inliner.
604     // This should probably be lowered after performance testing.
605     // FIXME: this comment is cargo culted from the old pass manager, revisit).
606     IP.HintThreshold = 325;
607 
608     CGSCCPassManager CGPipeline(DebugLogging);
609 
610     CGPipeline.addPass(InlinerPass(IP));
611 
612     FunctionPassManager FPM;
613     FPM.addPass(SROA());
614     FPM.addPass(EarlyCSEPass());    // Catch trivial redundancies.
615     FPM.addPass(SimplifyCFGPass()); // Merge & remove basic blocks.
616     FPM.addPass(InstCombinePass()); // Combine silly sequences.
617     invokePeepholeEPCallbacks(FPM, Level);
618 
619     CGPipeline.addPass(createCGSCCToFunctionPassAdaptor(std::move(FPM)));
620 
621     MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPipeline)));
622 
623     // Delete anything that is now dead to make sure that we don't instrument
624     // dead code. Instrumentation can end up keeping dead code around and
625     // dramatically increase code size.
626     MPM.addPass(GlobalDCEPass());
627   }
628 
629   if (!RunProfileGen) {
630     assert(!ProfileFile.empty() && "Profile use expecting a profile file!");
631     MPM.addPass(PGOInstrumentationUse(ProfileFile, ProfileRemappingFile, IsCS));
632     // Cache ProfileSummaryAnalysis once to avoid the potential need to insert
633     // RequireAnalysisPass for PSI before subsequent non-module passes.
634     MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
635     return;
636   }
637 
638   // Perform PGO instrumentation.
639   MPM.addPass(PGOInstrumentationGen(IsCS));
640 
641   FunctionPassManager FPM;
642   FPM.addPass(createFunctionToLoopPassAdaptor(
643       LoopRotatePass(), EnableMSSALoopDependency, DebugLogging));
644   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
645 
646   // Add the profile lowering pass.
647   InstrProfOptions Options;
648   if (!ProfileFile.empty())
649     Options.InstrProfileOutput = ProfileFile;
650   // Do counter promotion at Level greater than O0.
651   Options.DoCounterPromotion = true;
652   Options.UseBFIInPromotion = IsCS;
653   MPM.addPass(InstrProfiling(Options, IsCS));
654 }
655 
656 void PassBuilder::addPGOInstrPassesForO0(ModulePassManager &MPM,
657                                          bool DebugLogging, bool RunProfileGen,
658                                          bool IsCS, std::string ProfileFile,
659                                          std::string ProfileRemappingFile) {
660   if (!RunProfileGen) {
661     assert(!ProfileFile.empty() && "Profile use expecting a profile file!");
662     MPM.addPass(PGOInstrumentationUse(ProfileFile, ProfileRemappingFile, IsCS));
663     // Cache ProfileSummaryAnalysis once to avoid the potential need to insert
664     // RequireAnalysisPass for PSI before subsequent non-module passes.
665     MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
666     return;
667   }
668 
669   // Perform PGO instrumentation.
670   MPM.addPass(PGOInstrumentationGen(IsCS));
671   // Add the profile lowering pass.
672   InstrProfOptions Options;
673   if (!ProfileFile.empty())
674     Options.InstrProfileOutput = ProfileFile;
675   // Do not do counter promotion at O0.
676   Options.DoCounterPromotion = false;
677   Options.UseBFIInPromotion = IsCS;
678   MPM.addPass(InstrProfiling(Options, IsCS));
679 }
680 
681 static InlineParams
682 getInlineParamsFromOptLevel(PassBuilder::OptimizationLevel Level) {
683   return getInlineParams(Level.getSpeedupLevel(), Level.getSizeLevel());
684 }
685 
686 ModulePassManager
687 PassBuilder::buildModuleSimplificationPipeline(OptimizationLevel Level,
688                                                ThinLTOPhase Phase,
689                                                bool DebugLogging) {
690   ModulePassManager MPM(DebugLogging);
691 
692   bool HasSampleProfile = PGOOpt && (PGOOpt->Action == PGOOptions::SampleUse);
693 
694   // In ThinLTO mode, when flattened profile is used, all the available
695   // profile information will be annotated in PreLink phase so there is
696   // no need to load the profile again in PostLink.
697   bool LoadSampleProfile =
698       HasSampleProfile &&
699       !(FlattenedProfileUsed && Phase == ThinLTOPhase::PostLink);
700 
701   // During the ThinLTO backend phase we perform early indirect call promotion
702   // here, before globalopt. Otherwise imported available_externally functions
703   // look unreferenced and are removed. If we are going to load the sample
704   // profile then defer until later.
705   // TODO: See if we can move later and consolidate with the location where
706   // we perform ICP when we are loading a sample profile.
707   // TODO: We pass HasSampleProfile (whether there was a sample profile file
708   // passed to the compile) to the SamplePGO flag of ICP. This is used to
709   // determine whether the new direct calls are annotated with prof metadata.
710   // Ideally this should be determined from whether the IR is annotated with
711   // sample profile, and not whether the a sample profile was provided on the
712   // command line. E.g. for flattened profiles where we will not be reloading
713   // the sample profile in the ThinLTO backend, we ideally shouldn't have to
714   // provide the sample profile file.
715   if (Phase == ThinLTOPhase::PostLink && !LoadSampleProfile)
716     MPM.addPass(PGOIndirectCallPromotion(true /* InLTO */, HasSampleProfile));
717 
718   // Do basic inference of function attributes from known properties of system
719   // libraries and other oracles.
720   MPM.addPass(InferFunctionAttrsPass());
721 
722   // Create an early function pass manager to cleanup the output of the
723   // frontend.
724   FunctionPassManager EarlyFPM(DebugLogging);
725   EarlyFPM.addPass(SimplifyCFGPass());
726   EarlyFPM.addPass(SROA());
727   EarlyFPM.addPass(EarlyCSEPass());
728   EarlyFPM.addPass(LowerExpectIntrinsicPass());
729   if (PTO.Coroutines)
730     EarlyFPM.addPass(CoroEarlyPass());
731   if (Level == OptimizationLevel::O3)
732     EarlyFPM.addPass(CallSiteSplittingPass());
733 
734   // In SamplePGO ThinLTO backend, we need instcombine before profile annotation
735   // to convert bitcast to direct calls so that they can be inlined during the
736   // profile annotation prepration step.
737   // More details about SamplePGO design can be found in:
738   // https://research.google.com/pubs/pub45290.html
739   // FIXME: revisit how SampleProfileLoad/Inliner/ICP is structured.
740   if (LoadSampleProfile)
741     EarlyFPM.addPass(InstCombinePass());
742   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(EarlyFPM)));
743 
744   if (LoadSampleProfile) {
745     // Annotate sample profile right after early FPM to ensure freshness of
746     // the debug info.
747     MPM.addPass(SampleProfileLoaderPass(PGOOpt->ProfileFile,
748                                         PGOOpt->ProfileRemappingFile,
749                                         Phase == ThinLTOPhase::PreLink));
750     // Cache ProfileSummaryAnalysis once to avoid the potential need to insert
751     // RequireAnalysisPass for PSI before subsequent non-module passes.
752     MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
753     // Do not invoke ICP in the ThinLTOPrelink phase as it makes it hard
754     // for the profile annotation to be accurate in the ThinLTO backend.
755     if (Phase != ThinLTOPhase::PreLink)
756       // We perform early indirect call promotion here, before globalopt.
757       // This is important for the ThinLTO backend phase because otherwise
758       // imported available_externally functions look unreferenced and are
759       // removed.
760       MPM.addPass(PGOIndirectCallPromotion(Phase == ThinLTOPhase::PostLink,
761                                            true /* SamplePGO */));
762   }
763   MPM.addPass(AttributorPass());
764 
765   // Interprocedural constant propagation now that basic cleanup has occurred
766   // and prior to optimizing globals.
767   // FIXME: This position in the pipeline hasn't been carefully considered in
768   // years, it should be re-analyzed.
769   MPM.addPass(IPSCCPPass());
770 
771   // Attach metadata to indirect call sites indicating the set of functions
772   // they may target at run-time. This should follow IPSCCP.
773   MPM.addPass(CalledValuePropagationPass());
774 
775   // Optimize globals to try and fold them into constants.
776   MPM.addPass(GlobalOptPass());
777 
778   // Promote any localized globals to SSA registers.
779   // FIXME: Should this instead by a run of SROA?
780   // FIXME: We should probably run instcombine and simplify-cfg afterward to
781   // delete control flows that are dead once globals have been folded to
782   // constants.
783   MPM.addPass(createModuleToFunctionPassAdaptor(PromotePass()));
784 
785   // Remove any dead arguments exposed by cleanups and constand folding
786   // globals.
787   MPM.addPass(DeadArgumentEliminationPass());
788 
789   // Create a small function pass pipeline to cleanup after all the global
790   // optimizations.
791   FunctionPassManager GlobalCleanupPM(DebugLogging);
792   GlobalCleanupPM.addPass(InstCombinePass());
793   invokePeepholeEPCallbacks(GlobalCleanupPM, Level);
794 
795   GlobalCleanupPM.addPass(SimplifyCFGPass());
796   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(GlobalCleanupPM)));
797 
798   // Add all the requested passes for instrumentation PGO, if requested.
799   if (PGOOpt && Phase != ThinLTOPhase::PostLink &&
800       (PGOOpt->Action == PGOOptions::IRInstr ||
801        PGOOpt->Action == PGOOptions::IRUse)) {
802     addPGOInstrPasses(MPM, DebugLogging, Level,
803                       /* RunProfileGen */ PGOOpt->Action == PGOOptions::IRInstr,
804                       /* IsCS */ false, PGOOpt->ProfileFile,
805                       PGOOpt->ProfileRemappingFile);
806     MPM.addPass(PGOIndirectCallPromotion(false, false));
807   }
808   if (PGOOpt && Phase != ThinLTOPhase::PostLink &&
809       PGOOpt->CSAction == PGOOptions::CSIRInstr)
810     MPM.addPass(PGOInstrumentationGenCreateVar(PGOOpt->CSProfileGenFile));
811 
812   // Synthesize function entry counts for non-PGO compilation.
813   if (EnableSyntheticCounts && !PGOOpt)
814     MPM.addPass(SyntheticCountsPropagation());
815 
816   // Require the GlobalsAA analysis for the module so we can query it within
817   // the CGSCC pipeline.
818   MPM.addPass(RequireAnalysisPass<GlobalsAA, Module>());
819 
820   // Require the ProfileSummaryAnalysis for the module so we can query it within
821   // the inliner pass.
822   MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
823 
824   // Now begin the main postorder CGSCC pipeline.
825   // FIXME: The current CGSCC pipeline has its origins in the legacy pass
826   // manager and trying to emulate its precise behavior. Much of this doesn't
827   // make a lot of sense and we should revisit the core CGSCC structure.
828   CGSCCPassManager MainCGPipeline(DebugLogging);
829 
830   // Note: historically, the PruneEH pass was run first to deduce nounwind and
831   // generally clean up exception handling overhead. It isn't clear this is
832   // valuable as the inliner doesn't currently care whether it is inlining an
833   // invoke or a call.
834 
835   // Run the inliner first. The theory is that we are walking bottom-up and so
836   // the callees have already been fully optimized, and we want to inline them
837   // into the callers so that our optimizations can reflect that.
838   // For PreLinkThinLTO pass, we disable hot-caller heuristic for sample PGO
839   // because it makes profile annotation in the backend inaccurate.
840   InlineParams IP = getInlineParamsFromOptLevel(Level);
841   if (Phase == ThinLTOPhase::PreLink && PGOOpt &&
842       PGOOpt->Action == PGOOptions::SampleUse)
843     IP.HotCallSiteThreshold = 0;
844   MainCGPipeline.addPass(InlinerPass(IP));
845 
846   MainCGPipeline.addPass(AttributorCGSCCPass());
847 
848   if (PTO.Coroutines)
849     MainCGPipeline.addPass(CoroSplitPass());
850 
851   // Now deduce any function attributes based in the current code.
852   MainCGPipeline.addPass(PostOrderFunctionAttrsPass());
853 
854   // When at O3 add argument promotion to the pass pipeline.
855   // FIXME: It isn't at all clear why this should be limited to O3.
856   if (Level == OptimizationLevel::O3)
857     MainCGPipeline.addPass(ArgumentPromotionPass());
858 
859   // Try to perform OpenMP specific optimizations. This is a (quick!) no-op if
860   // there are no OpenMP runtime calls present in the module.
861   if (Level == OptimizationLevel::O2 || Level == OptimizationLevel::O3)
862     MainCGPipeline.addPass(OpenMPOptPass());
863 
864   // Lastly, add the core function simplification pipeline nested inside the
865   // CGSCC walk.
866   MainCGPipeline.addPass(createCGSCCToFunctionPassAdaptor(
867       buildFunctionSimplificationPipeline(Level, Phase, DebugLogging)));
868 
869   for (auto &C : CGSCCOptimizerLateEPCallbacks)
870     C(MainCGPipeline, Level);
871 
872   // We wrap the CGSCC pipeline in a devirtualization repeater. This will try
873   // to detect when we devirtualize indirect calls and iterate the SCC passes
874   // in that case to try and catch knock-on inlining or function attrs
875   // opportunities. Then we add it to the module pipeline by walking the SCCs
876   // in postorder (or bottom-up).
877   MPM.addPass(
878       createModuleToPostOrderCGSCCPassAdaptor(createDevirtSCCRepeatedPass(
879           std::move(MainCGPipeline), MaxDevirtIterations)));
880 
881   return MPM;
882 }
883 
884 ModulePassManager PassBuilder::buildModuleOptimizationPipeline(
885     OptimizationLevel Level, bool DebugLogging, bool LTOPreLink) {
886   ModulePassManager MPM(DebugLogging);
887 
888   // Optimize globals now that the module is fully simplified.
889   MPM.addPass(GlobalOptPass());
890   MPM.addPass(GlobalDCEPass());
891 
892   // Run partial inlining pass to partially inline functions that have
893   // large bodies.
894   if (RunPartialInlining)
895     MPM.addPass(PartialInlinerPass());
896 
897   // Remove avail extern fns and globals definitions since we aren't compiling
898   // an object file for later LTO. For LTO we want to preserve these so they
899   // are eligible for inlining at link-time. Note if they are unreferenced they
900   // will be removed by GlobalDCE later, so this only impacts referenced
901   // available externally globals. Eventually they will be suppressed during
902   // codegen, but eliminating here enables more opportunity for GlobalDCE as it
903   // may make globals referenced by available external functions dead and saves
904   // running remaining passes on the eliminated functions. These should be
905   // preserved during prelinking for link-time inlining decisions.
906   if (!LTOPreLink)
907     MPM.addPass(EliminateAvailableExternallyPass());
908 
909   if (EnableOrderFileInstrumentation)
910     MPM.addPass(InstrOrderFilePass());
911 
912   // Do RPO function attribute inference across the module to forward-propagate
913   // attributes where applicable.
914   // FIXME: Is this really an optimization rather than a canonicalization?
915   MPM.addPass(ReversePostOrderFunctionAttrsPass());
916 
917   // Do a post inline PGO instrumentation and use pass. This is a context
918   // sensitive PGO pass. We don't want to do this in LTOPreLink phrase as
919   // cross-module inline has not been done yet. The context sensitive
920   // instrumentation is after all the inlines are done.
921   if (!LTOPreLink && PGOOpt) {
922     if (PGOOpt->CSAction == PGOOptions::CSIRInstr)
923       addPGOInstrPasses(MPM, DebugLogging, Level, /* RunProfileGen */ true,
924                         /* IsCS */ true, PGOOpt->CSProfileGenFile,
925                         PGOOpt->ProfileRemappingFile);
926     else if (PGOOpt->CSAction == PGOOptions::CSIRUse)
927       addPGOInstrPasses(MPM, DebugLogging, Level, /* RunProfileGen */ false,
928                         /* IsCS */ true, PGOOpt->ProfileFile,
929                         PGOOpt->ProfileRemappingFile);
930   }
931 
932   // Re-require GloblasAA here prior to function passes. This is particularly
933   // useful as the above will have inlined, DCE'ed, and function-attr
934   // propagated everything. We should at this point have a reasonably minimal
935   // and richly annotated call graph. By computing aliasing and mod/ref
936   // information for all local globals here, the late loop passes and notably
937   // the vectorizer will be able to use them to help recognize vectorizable
938   // memory operations.
939   MPM.addPass(RequireAnalysisPass<GlobalsAA, Module>());
940 
941   FunctionPassManager OptimizePM(DebugLogging);
942   OptimizePM.addPass(Float2IntPass());
943   OptimizePM.addPass(LowerConstantIntrinsicsPass());
944 
945   // FIXME: We need to run some loop optimizations to re-rotate loops after
946   // simplify-cfg and others undo their rotation.
947 
948   // Optimize the loop execution. These passes operate on entire loop nests
949   // rather than on each loop in an inside-out manner, and so they are actually
950   // function passes.
951 
952   for (auto &C : VectorizerStartEPCallbacks)
953     C(OptimizePM, Level);
954 
955   // First rotate loops that may have been un-rotated by prior passes.
956   OptimizePM.addPass(createFunctionToLoopPassAdaptor(
957       LoopRotatePass(), EnableMSSALoopDependency, DebugLogging));
958 
959   // Distribute loops to allow partial vectorization.  I.e. isolate dependences
960   // into separate loop that would otherwise inhibit vectorization.  This is
961   // currently only performed for loops marked with the metadata
962   // llvm.loop.distribute=true or when -enable-loop-distribute is specified.
963   OptimizePM.addPass(LoopDistributePass());
964 
965   // Now run the core loop vectorizer.
966   OptimizePM.addPass(LoopVectorizePass(
967       LoopVectorizeOptions(!PTO.LoopInterleaving, !PTO.LoopVectorization)));
968 
969   // Enhance/cleanup vector code.
970   OptimizePM.addPass(VectorCombinePass());
971   OptimizePM.addPass(EarlyCSEPass());
972 
973   // Eliminate loads by forwarding stores from the previous iteration to loads
974   // of the current iteration.
975   OptimizePM.addPass(LoopLoadEliminationPass());
976 
977   // Cleanup after the loop optimization passes.
978   OptimizePM.addPass(InstCombinePass());
979 
980   // Now that we've formed fast to execute loop structures, we do further
981   // optimizations. These are run afterward as they might block doing complex
982   // analyses and transforms such as what are needed for loop vectorization.
983 
984   // Cleanup after loop vectorization, etc. Simplification passes like CVP and
985   // GVN, loop transforms, and others have already run, so it's now better to
986   // convert to more optimized IR using more aggressive simplify CFG options.
987   // The extra sinking transform can create larger basic blocks, so do this
988   // before SLP vectorization.
989   OptimizePM.addPass(SimplifyCFGPass(SimplifyCFGOptions().
990                                      forwardSwitchCondToPhi(true).
991                                      convertSwitchToLookupTable(true).
992                                      needCanonicalLoops(false).
993                                      sinkCommonInsts(true)));
994 
995   // Optimize parallel scalar instruction chains into SIMD instructions.
996   if (PTO.SLPVectorization)
997     OptimizePM.addPass(SLPVectorizerPass());
998 
999   OptimizePM.addPass(InstCombinePass());
1000 
1001   // Unroll small loops to hide loop backedge latency and saturate any parallel
1002   // execution resources of an out-of-order processor. We also then need to
1003   // clean up redundancies and loop invariant code.
1004   // FIXME: It would be really good to use a loop-integrated instruction
1005   // combiner for cleanup here so that the unrolling and LICM can be pipelined
1006   // across the loop nests.
1007   // We do UnrollAndJam in a separate LPM to ensure it happens before unroll
1008   if (EnableUnrollAndJam && PTO.LoopUnrolling) {
1009     OptimizePM.addPass(LoopUnrollAndJamPass(Level.getSpeedupLevel()));
1010   }
1011   OptimizePM.addPass(LoopUnrollPass(LoopUnrollOptions(
1012       Level.getSpeedupLevel(), /*OnlyWhenForced=*/!PTO.LoopUnrolling,
1013       PTO.ForgetAllSCEVInLoopUnroll)));
1014   OptimizePM.addPass(WarnMissedTransformationsPass());
1015   OptimizePM.addPass(InstCombinePass());
1016   OptimizePM.addPass(RequireAnalysisPass<OptimizationRemarkEmitterAnalysis, Function>());
1017   OptimizePM.addPass(createFunctionToLoopPassAdaptor(
1018       LICMPass(PTO.LicmMssaOptCap, PTO.LicmMssaNoAccForPromotionCap),
1019       EnableMSSALoopDependency, DebugLogging));
1020 
1021   // Now that we've vectorized and unrolled loops, we may have more refined
1022   // alignment information, try to re-derive it here.
1023   OptimizePM.addPass(AlignmentFromAssumptionsPass());
1024 
1025   // Split out cold code. Splitting is done late to avoid hiding context from
1026   // other optimizations and inadvertently regressing performance. The tradeoff
1027   // is that this has a higher code size cost than splitting early.
1028   if (EnableHotColdSplit && !LTOPreLink)
1029     MPM.addPass(HotColdSplittingPass());
1030 
1031   // LoopSink pass sinks instructions hoisted by LICM, which serves as a
1032   // canonicalization pass that enables other optimizations. As a result,
1033   // LoopSink pass needs to be a very late IR pass to avoid undoing LICM
1034   // result too early.
1035   OptimizePM.addPass(LoopSinkPass());
1036 
1037   // And finally clean up LCSSA form before generating code.
1038   OptimizePM.addPass(InstSimplifyPass());
1039 
1040   // This hoists/decomposes div/rem ops. It should run after other sink/hoist
1041   // passes to avoid re-sinking, but before SimplifyCFG because it can allow
1042   // flattening of blocks.
1043   OptimizePM.addPass(DivRemPairsPass());
1044 
1045   // LoopSink (and other loop passes since the last simplifyCFG) might have
1046   // resulted in single-entry-single-exit or empty blocks. Clean up the CFG.
1047   OptimizePM.addPass(SimplifyCFGPass());
1048 
1049   // Optimize PHIs by speculating around them when profitable. Note that this
1050   // pass needs to be run after any PRE or similar pass as it is essentially
1051   // inserting redundancies into the program. This even includes SimplifyCFG.
1052   OptimizePM.addPass(SpeculateAroundPHIsPass());
1053 
1054   if (PTO.Coroutines)
1055     OptimizePM.addPass(CoroCleanupPass());
1056 
1057   for (auto &C : OptimizerLastEPCallbacks)
1058     C(OptimizePM, Level);
1059 
1060   // Add the core optimizing pipeline.
1061   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(OptimizePM)));
1062 
1063   MPM.addPass(CGProfilePass());
1064 
1065   // Now we need to do some global optimization transforms.
1066   // FIXME: It would seem like these should come first in the optimization
1067   // pipeline and maybe be the bottom of the canonicalization pipeline? Weird
1068   // ordering here.
1069   MPM.addPass(GlobalDCEPass());
1070   MPM.addPass(ConstantMergePass());
1071 
1072   return MPM;
1073 }
1074 
1075 ModulePassManager
1076 PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,
1077                                            bool DebugLogging, bool LTOPreLink) {
1078   assert(Level != OptimizationLevel::O0 &&
1079          "Must request optimizations for the default pipeline!");
1080 
1081   ModulePassManager MPM(DebugLogging);
1082 
1083   // Force any function attributes we want the rest of the pipeline to observe.
1084   MPM.addPass(ForceFunctionAttrsPass());
1085 
1086   // Apply module pipeline start EP callback.
1087   for (auto &C : PipelineStartEPCallbacks)
1088     C(MPM);
1089 
1090   if (PGOOpt && PGOOpt->SamplePGOSupport)
1091     MPM.addPass(createModuleToFunctionPassAdaptor(AddDiscriminatorsPass()));
1092 
1093   // Add the core simplification pipeline.
1094   MPM.addPass(buildModuleSimplificationPipeline(Level, ThinLTOPhase::None,
1095                                                 DebugLogging));
1096 
1097   // Now add the optimization pipeline.
1098   MPM.addPass(buildModuleOptimizationPipeline(Level, DebugLogging, LTOPreLink));
1099 
1100   return MPM;
1101 }
1102 
1103 ModulePassManager
1104 PassBuilder::buildThinLTOPreLinkDefaultPipeline(OptimizationLevel Level,
1105                                                 bool DebugLogging) {
1106   assert(Level != OptimizationLevel::O0 &&
1107          "Must request optimizations for the default pipeline!");
1108 
1109   ModulePassManager MPM(DebugLogging);
1110 
1111   // Force any function attributes we want the rest of the pipeline to observe.
1112   MPM.addPass(ForceFunctionAttrsPass());
1113 
1114   if (PGOOpt && PGOOpt->SamplePGOSupport)
1115     MPM.addPass(createModuleToFunctionPassAdaptor(AddDiscriminatorsPass()));
1116 
1117   // Apply module pipeline start EP callback.
1118   for (auto &C : PipelineStartEPCallbacks)
1119     C(MPM);
1120 
1121   // If we are planning to perform ThinLTO later, we don't bloat the code with
1122   // unrolling/vectorization/... now. Just simplify the module as much as we
1123   // can.
1124   MPM.addPass(buildModuleSimplificationPipeline(Level, ThinLTOPhase::PreLink,
1125                                                 DebugLogging));
1126 
1127   // Run partial inlining pass to partially inline functions that have
1128   // large bodies.
1129   // FIXME: It isn't clear whether this is really the right place to run this
1130   // in ThinLTO. Because there is another canonicalization and simplification
1131   // phase that will run after the thin link, running this here ends up with
1132   // less information than will be available later and it may grow functions in
1133   // ways that aren't beneficial.
1134   if (RunPartialInlining)
1135     MPM.addPass(PartialInlinerPass());
1136 
1137   // Reduce the size of the IR as much as possible.
1138   MPM.addPass(GlobalOptPass());
1139 
1140   // Module simplification splits coroutines, but does not fully clean up
1141   // coroutine intrinsics. To ensure ThinLTO optimization passes don't trip up
1142   // on these, we schedule the cleanup here.
1143   if (PTO.Coroutines)
1144     MPM.addPass(createModuleToFunctionPassAdaptor(CoroCleanupPass()));
1145 
1146   return MPM;
1147 }
1148 
1149 ModulePassManager PassBuilder::buildThinLTODefaultPipeline(
1150     OptimizationLevel Level, bool DebugLogging,
1151     const ModuleSummaryIndex *ImportSummary) {
1152   ModulePassManager MPM(DebugLogging);
1153 
1154   if (ImportSummary) {
1155     // These passes import type identifier resolutions for whole-program
1156     // devirtualization and CFI. They must run early because other passes may
1157     // disturb the specific instruction patterns that these passes look for,
1158     // creating dependencies on resolutions that may not appear in the summary.
1159     //
1160     // For example, GVN may transform the pattern assume(type.test) appearing in
1161     // two basic blocks into assume(phi(type.test, type.test)), which would
1162     // transform a dependency on a WPD resolution into a dependency on a type
1163     // identifier resolution for CFI.
1164     //
1165     // Also, WPD has access to more precise information than ICP and can
1166     // devirtualize more effectively, so it should operate on the IR first.
1167     //
1168     // The WPD and LowerTypeTest passes need to run at -O0 to lower type
1169     // metadata and intrinsics.
1170     MPM.addPass(WholeProgramDevirtPass(nullptr, ImportSummary));
1171     MPM.addPass(LowerTypeTestsPass(nullptr, ImportSummary));
1172   }
1173 
1174   if (Level == OptimizationLevel::O0)
1175     return MPM;
1176 
1177   // Force any function attributes we want the rest of the pipeline to observe.
1178   MPM.addPass(ForceFunctionAttrsPass());
1179 
1180   // Add the core simplification pipeline.
1181   MPM.addPass(buildModuleSimplificationPipeline(Level, ThinLTOPhase::PostLink,
1182                                                 DebugLogging));
1183 
1184   // Now add the optimization pipeline.
1185   MPM.addPass(buildModuleOptimizationPipeline(Level, DebugLogging));
1186 
1187   return MPM;
1188 }
1189 
1190 ModulePassManager
1191 PassBuilder::buildLTOPreLinkDefaultPipeline(OptimizationLevel Level,
1192                                             bool DebugLogging) {
1193   assert(Level != OptimizationLevel::O0 &&
1194          "Must request optimizations for the default pipeline!");
1195   // FIXME: We should use a customized pre-link pipeline!
1196   return buildPerModuleDefaultPipeline(Level, DebugLogging,
1197                                        /* LTOPreLink */ true);
1198 }
1199 
1200 ModulePassManager
1201 PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level, bool DebugLogging,
1202                                      ModuleSummaryIndex *ExportSummary) {
1203   ModulePassManager MPM(DebugLogging);
1204 
1205   if (Level == OptimizationLevel::O0) {
1206     // The WPD and LowerTypeTest passes need to run at -O0 to lower type
1207     // metadata and intrinsics.
1208     MPM.addPass(WholeProgramDevirtPass(ExportSummary, nullptr));
1209     MPM.addPass(LowerTypeTestsPass(ExportSummary, nullptr));
1210     return MPM;
1211   }
1212 
1213   if (PGOOpt && PGOOpt->Action == PGOOptions::SampleUse) {
1214     // Load sample profile before running the LTO optimization pipeline.
1215     MPM.addPass(SampleProfileLoaderPass(PGOOpt->ProfileFile,
1216                                         PGOOpt->ProfileRemappingFile,
1217                                         false /* ThinLTOPhase::PreLink */));
1218     // Cache ProfileSummaryAnalysis once to avoid the potential need to insert
1219     // RequireAnalysisPass for PSI before subsequent non-module passes.
1220     MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
1221   }
1222 
1223   // Remove unused virtual tables to improve the quality of code generated by
1224   // whole-program devirtualization and bitset lowering.
1225   MPM.addPass(GlobalDCEPass());
1226 
1227   // Force any function attributes we want the rest of the pipeline to observe.
1228   MPM.addPass(ForceFunctionAttrsPass());
1229 
1230   // Do basic inference of function attributes from known properties of system
1231   // libraries and other oracles.
1232   MPM.addPass(InferFunctionAttrsPass());
1233 
1234   if (Level.getSpeedupLevel() > 1) {
1235     FunctionPassManager EarlyFPM(DebugLogging);
1236     EarlyFPM.addPass(CallSiteSplittingPass());
1237     MPM.addPass(createModuleToFunctionPassAdaptor(std::move(EarlyFPM)));
1238 
1239     // Indirect call promotion. This should promote all the targets that are
1240     // left by the earlier promotion pass that promotes intra-module targets.
1241     // This two-step promotion is to save the compile time. For LTO, it should
1242     // produce the same result as if we only do promotion here.
1243     MPM.addPass(PGOIndirectCallPromotion(
1244         true /* InLTO */, PGOOpt && PGOOpt->Action == PGOOptions::SampleUse));
1245     // Propagate constants at call sites into the functions they call.  This
1246     // opens opportunities for globalopt (and inlining) by substituting function
1247     // pointers passed as arguments to direct uses of functions.
1248    MPM.addPass(IPSCCPPass());
1249 
1250    // Attach metadata to indirect call sites indicating the set of functions
1251    // they may target at run-time. This should follow IPSCCP.
1252    MPM.addPass(CalledValuePropagationPass());
1253   }
1254 
1255   // Now deduce any function attributes based in the current code.
1256   MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(
1257               PostOrderFunctionAttrsPass()));
1258 
1259   // Do RPO function attribute inference across the module to forward-propagate
1260   // attributes where applicable.
1261   // FIXME: Is this really an optimization rather than a canonicalization?
1262   MPM.addPass(ReversePostOrderFunctionAttrsPass());
1263 
1264   // Use in-range annotations on GEP indices to split globals where beneficial.
1265   MPM.addPass(GlobalSplitPass());
1266 
1267   // Run whole program optimization of virtual call when the list of callees
1268   // is fixed.
1269   MPM.addPass(WholeProgramDevirtPass(ExportSummary, nullptr));
1270 
1271   // Stop here at -O1.
1272   if (Level == OptimizationLevel::O1) {
1273     // The LowerTypeTestsPass needs to run to lower type metadata and the
1274     // type.test intrinsics. The pass does nothing if CFI is disabled.
1275     MPM.addPass(LowerTypeTestsPass(ExportSummary, nullptr));
1276     return MPM;
1277   }
1278 
1279   // Optimize globals to try and fold them into constants.
1280   MPM.addPass(GlobalOptPass());
1281 
1282   // Promote any localized globals to SSA registers.
1283   MPM.addPass(createModuleToFunctionPassAdaptor(PromotePass()));
1284 
1285   // Linking modules together can lead to duplicate global constant, only
1286   // keep one copy of each constant.
1287   MPM.addPass(ConstantMergePass());
1288 
1289   // Remove unused arguments from functions.
1290   MPM.addPass(DeadArgumentEliminationPass());
1291 
1292   // Reduce the code after globalopt and ipsccp.  Both can open up significant
1293   // simplification opportunities, and both can propagate functions through
1294   // function pointers.  When this happens, we often have to resolve varargs
1295   // calls, etc, so let instcombine do this.
1296   FunctionPassManager PeepholeFPM(DebugLogging);
1297   if (Level == OptimizationLevel::O3)
1298     PeepholeFPM.addPass(AggressiveInstCombinePass());
1299   PeepholeFPM.addPass(InstCombinePass());
1300   invokePeepholeEPCallbacks(PeepholeFPM, Level);
1301 
1302   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(PeepholeFPM)));
1303 
1304   // Note: historically, the PruneEH pass was run first to deduce nounwind and
1305   // generally clean up exception handling overhead. It isn't clear this is
1306   // valuable as the inliner doesn't currently care whether it is inlining an
1307   // invoke or a call.
1308   // Run the inliner now.
1309   MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(
1310       InlinerPass(getInlineParamsFromOptLevel(Level))));
1311 
1312   // Optimize globals again after we ran the inliner.
1313   MPM.addPass(GlobalOptPass());
1314 
1315   // Garbage collect dead functions.
1316   // FIXME: Add ArgumentPromotion pass after once it's ported.
1317   MPM.addPass(GlobalDCEPass());
1318 
1319   FunctionPassManager FPM(DebugLogging);
1320   // The IPO Passes may leave cruft around. Clean up after them.
1321   FPM.addPass(InstCombinePass());
1322   invokePeepholeEPCallbacks(FPM, Level);
1323 
1324   FPM.addPass(JumpThreadingPass());
1325 
1326   // Do a post inline PGO instrumentation and use pass. This is a context
1327   // sensitive PGO pass.
1328   if (PGOOpt) {
1329     if (PGOOpt->CSAction == PGOOptions::CSIRInstr)
1330       addPGOInstrPasses(MPM, DebugLogging, Level, /* RunProfileGen */ true,
1331                         /* IsCS */ true, PGOOpt->CSProfileGenFile,
1332                         PGOOpt->ProfileRemappingFile);
1333     else if (PGOOpt->CSAction == PGOOptions::CSIRUse)
1334       addPGOInstrPasses(MPM, DebugLogging, Level, /* RunProfileGen */ false,
1335                         /* IsCS */ true, PGOOpt->ProfileFile,
1336                         PGOOpt->ProfileRemappingFile);
1337   }
1338 
1339   // Break up allocas
1340   FPM.addPass(SROA());
1341 
1342   // LTO provides additional opportunities for tailcall elimination due to
1343   // link-time inlining, and visibility of nocapture attribute.
1344   FPM.addPass(TailCallElimPass());
1345 
1346   // Run a few AA driver optimizations here and now to cleanup the code.
1347   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
1348 
1349   MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(
1350               PostOrderFunctionAttrsPass()));
1351   // FIXME: here we run IP alias analysis in the legacy PM.
1352 
1353   FunctionPassManager MainFPM;
1354 
1355   // FIXME: once we fix LoopPass Manager, add LICM here.
1356   // FIXME: once we provide support for enabling MLSM, add it here.
1357   if (RunNewGVN)
1358     MainFPM.addPass(NewGVNPass());
1359   else
1360     MainFPM.addPass(GVN());
1361 
1362   // Remove dead memcpy()'s.
1363   MainFPM.addPass(MemCpyOptPass());
1364 
1365   // Nuke dead stores.
1366   MainFPM.addPass(DSEPass());
1367 
1368   // FIXME: at this point, we run a bunch of loop passes:
1369   // indVarSimplify, loopDeletion, loopInterchange, loopUnroll,
1370   // loopVectorize. Enable them once the remaining issue with LPM
1371   // are sorted out.
1372 
1373   MainFPM.addPass(InstCombinePass());
1374   MainFPM.addPass(SimplifyCFGPass());
1375   MainFPM.addPass(SCCPPass());
1376   MainFPM.addPass(InstCombinePass());
1377   MainFPM.addPass(BDCEPass());
1378 
1379   // FIXME: We may want to run SLPVectorizer here.
1380   // After vectorization, assume intrinsics may tell us more
1381   // about pointer alignments.
1382 #if 0
1383   MainFPM.add(AlignmentFromAssumptionsPass());
1384 #endif
1385 
1386   // FIXME: Conditionally run LoadCombine here, after it's ported
1387   // (in case we still have this pass, given its questionable usefulness).
1388 
1389   MainFPM.addPass(InstCombinePass());
1390   invokePeepholeEPCallbacks(MainFPM, Level);
1391   MainFPM.addPass(JumpThreadingPass());
1392   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(MainFPM)));
1393 
1394   // Create a function that performs CFI checks for cross-DSO calls with
1395   // targets in the current module.
1396   MPM.addPass(CrossDSOCFIPass());
1397 
1398   // Lower type metadata and the type.test intrinsic. This pass supports
1399   // clang's control flow integrity mechanisms (-fsanitize=cfi*) and needs
1400   // to be run at link time if CFI is enabled. This pass does nothing if
1401   // CFI is disabled.
1402   MPM.addPass(LowerTypeTestsPass(ExportSummary, nullptr));
1403 
1404   // Enable splitting late in the FullLTO post-link pipeline. This is done in
1405   // the same stage in the old pass manager (\ref addLateLTOOptimizationPasses).
1406   if (EnableHotColdSplit)
1407     MPM.addPass(HotColdSplittingPass());
1408 
1409   // Add late LTO optimization passes.
1410   // Delete basic blocks, which optimization passes may have killed.
1411   MPM.addPass(createModuleToFunctionPassAdaptor(SimplifyCFGPass()));
1412 
1413   // Drop bodies of available eternally objects to improve GlobalDCE.
1414   MPM.addPass(EliminateAvailableExternallyPass());
1415 
1416   // Now that we have optimized the program, discard unreachable functions.
1417   MPM.addPass(GlobalDCEPass());
1418 
1419   // FIXME: Maybe enable MergeFuncs conditionally after it's ported.
1420   return MPM;
1421 }
1422 
1423 AAManager PassBuilder::buildDefaultAAPipeline() {
1424   AAManager AA;
1425 
1426   // The order in which these are registered determines their priority when
1427   // being queried.
1428 
1429   // First we register the basic alias analysis that provides the majority of
1430   // per-function local AA logic. This is a stateless, on-demand local set of
1431   // AA techniques.
1432   AA.registerFunctionAnalysis<BasicAA>();
1433 
1434   // Next we query fast, specialized alias analyses that wrap IR-embedded
1435   // information about aliasing.
1436   AA.registerFunctionAnalysis<ScopedNoAliasAA>();
1437   AA.registerFunctionAnalysis<TypeBasedAA>();
1438 
1439   // Add support for querying global aliasing information when available.
1440   // Because the `AAManager` is a function analysis and `GlobalsAA` is a module
1441   // analysis, all that the `AAManager` can do is query for any *cached*
1442   // results from `GlobalsAA` through a readonly proxy.
1443   AA.registerModuleAnalysis<GlobalsAA>();
1444 
1445   return AA;
1446 }
1447 
1448 static Optional<int> parseRepeatPassName(StringRef Name) {
1449   if (!Name.consume_front("repeat<") || !Name.consume_back(">"))
1450     return None;
1451   int Count;
1452   if (Name.getAsInteger(0, Count) || Count <= 0)
1453     return None;
1454   return Count;
1455 }
1456 
1457 static Optional<int> parseDevirtPassName(StringRef Name) {
1458   if (!Name.consume_front("devirt<") || !Name.consume_back(">"))
1459     return None;
1460   int Count;
1461   if (Name.getAsInteger(0, Count) || Count <= 0)
1462     return None;
1463   return Count;
1464 }
1465 
1466 static bool checkParametrizedPassName(StringRef Name, StringRef PassName) {
1467   if (!Name.consume_front(PassName))
1468     return false;
1469   // normal pass name w/o parameters == default parameters
1470   if (Name.empty())
1471     return true;
1472   return Name.startswith("<") && Name.endswith(">");
1473 }
1474 
1475 namespace {
1476 
1477 /// This performs customized parsing of pass name with parameters.
1478 ///
1479 /// We do not need parametrization of passes in textual pipeline very often,
1480 /// yet on a rare occasion ability to specify parameters right there can be
1481 /// useful.
1482 ///
1483 /// \p Name - parameterized specification of a pass from a textual pipeline
1484 /// is a string in a form of :
1485 ///      PassName '<' parameter-list '>'
1486 ///
1487 /// Parameter list is being parsed by the parser callable argument, \p Parser,
1488 /// It takes a string-ref of parameters and returns either StringError or a
1489 /// parameter list in a form of a custom parameters type, all wrapped into
1490 /// Expected<> template class.
1491 ///
1492 template <typename ParametersParseCallableT>
1493 auto parsePassParameters(ParametersParseCallableT &&Parser, StringRef Name,
1494                          StringRef PassName) -> decltype(Parser(StringRef{})) {
1495   using ParametersT = typename decltype(Parser(StringRef{}))::value_type;
1496 
1497   StringRef Params = Name;
1498   if (!Params.consume_front(PassName)) {
1499     assert(false &&
1500            "unable to strip pass name from parametrized pass specification");
1501   }
1502   if (Params.empty())
1503     return ParametersT{};
1504   if (!Params.consume_front("<") || !Params.consume_back(">")) {
1505     assert(false && "invalid format for parametrized pass name");
1506   }
1507 
1508   Expected<ParametersT> Result = Parser(Params);
1509   assert((Result || Result.template errorIsA<StringError>()) &&
1510          "Pass parameter parser can only return StringErrors.");
1511   return Result;
1512 }
1513 
1514 /// Parser of parameters for LoopUnroll pass.
1515 Expected<LoopUnrollOptions> parseLoopUnrollOptions(StringRef Params) {
1516   LoopUnrollOptions UnrollOpts;
1517   while (!Params.empty()) {
1518     StringRef ParamName;
1519     std::tie(ParamName, Params) = Params.split(';');
1520     int OptLevel = StringSwitch<int>(ParamName)
1521                        .Case("O0", 0)
1522                        .Case("O1", 1)
1523                        .Case("O2", 2)
1524                        .Case("O3", 3)
1525                        .Default(-1);
1526     if (OptLevel >= 0) {
1527       UnrollOpts.setOptLevel(OptLevel);
1528       continue;
1529     }
1530     if (ParamName.consume_front("full-unroll-max=")) {
1531       int Count;
1532       if (ParamName.getAsInteger(0, Count))
1533         return make_error<StringError>(
1534             formatv("invalid LoopUnrollPass parameter '{0}' ", ParamName).str(),
1535             inconvertibleErrorCode());
1536       UnrollOpts.setFullUnrollMaxCount(Count);
1537       continue;
1538     }
1539 
1540     bool Enable = !ParamName.consume_front("no-");
1541     if (ParamName == "partial") {
1542       UnrollOpts.setPartial(Enable);
1543     } else if (ParamName == "peeling") {
1544       UnrollOpts.setPeeling(Enable);
1545     } else if (ParamName == "profile-peeling") {
1546       UnrollOpts.setProfileBasedPeeling(Enable);
1547     } else if (ParamName == "runtime") {
1548       UnrollOpts.setRuntime(Enable);
1549     } else if (ParamName == "upperbound") {
1550       UnrollOpts.setUpperBound(Enable);
1551     } else {
1552       return make_error<StringError>(
1553           formatv("invalid LoopUnrollPass parameter '{0}' ", ParamName).str(),
1554           inconvertibleErrorCode());
1555     }
1556   }
1557   return UnrollOpts;
1558 }
1559 
1560 Expected<MemorySanitizerOptions> parseMSanPassOptions(StringRef Params) {
1561   MemorySanitizerOptions Result;
1562   while (!Params.empty()) {
1563     StringRef ParamName;
1564     std::tie(ParamName, Params) = Params.split(';');
1565 
1566     if (ParamName == "recover") {
1567       Result.Recover = true;
1568     } else if (ParamName == "kernel") {
1569       Result.Kernel = true;
1570     } else if (ParamName.consume_front("track-origins=")) {
1571       if (ParamName.getAsInteger(0, Result.TrackOrigins))
1572         return make_error<StringError>(
1573             formatv("invalid argument to MemorySanitizer pass track-origins "
1574                     "parameter: '{0}' ",
1575                     ParamName)
1576                 .str(),
1577             inconvertibleErrorCode());
1578     } else {
1579       return make_error<StringError>(
1580           formatv("invalid MemorySanitizer pass parameter '{0}' ", ParamName)
1581               .str(),
1582           inconvertibleErrorCode());
1583     }
1584   }
1585   return Result;
1586 }
1587 
1588 /// Parser of parameters for SimplifyCFG pass.
1589 Expected<SimplifyCFGOptions> parseSimplifyCFGOptions(StringRef Params) {
1590   SimplifyCFGOptions Result;
1591   while (!Params.empty()) {
1592     StringRef ParamName;
1593     std::tie(ParamName, Params) = Params.split(';');
1594 
1595     bool Enable = !ParamName.consume_front("no-");
1596     if (ParamName == "forward-switch-cond") {
1597       Result.forwardSwitchCondToPhi(Enable);
1598     } else if (ParamName == "switch-to-lookup") {
1599       Result.convertSwitchToLookupTable(Enable);
1600     } else if (ParamName == "keep-loops") {
1601       Result.needCanonicalLoops(Enable);
1602     } else if (ParamName == "sink-common-insts") {
1603       Result.sinkCommonInsts(Enable);
1604     } else if (Enable && ParamName.consume_front("bonus-inst-threshold=")) {
1605       APInt BonusInstThreshold;
1606       if (ParamName.getAsInteger(0, BonusInstThreshold))
1607         return make_error<StringError>(
1608             formatv("invalid argument to SimplifyCFG pass bonus-threshold "
1609                     "parameter: '{0}' ",
1610                     ParamName).str(),
1611             inconvertibleErrorCode());
1612       Result.bonusInstThreshold(BonusInstThreshold.getSExtValue());
1613     } else {
1614       return make_error<StringError>(
1615           formatv("invalid SimplifyCFG pass parameter '{0}' ", ParamName).str(),
1616           inconvertibleErrorCode());
1617     }
1618   }
1619   return Result;
1620 }
1621 
1622 /// Parser of parameters for LoopVectorize pass.
1623 Expected<LoopVectorizeOptions> parseLoopVectorizeOptions(StringRef Params) {
1624   LoopVectorizeOptions Opts;
1625   while (!Params.empty()) {
1626     StringRef ParamName;
1627     std::tie(ParamName, Params) = Params.split(';');
1628 
1629     bool Enable = !ParamName.consume_front("no-");
1630     if (ParamName == "interleave-forced-only") {
1631       Opts.setInterleaveOnlyWhenForced(Enable);
1632     } else if (ParamName == "vectorize-forced-only") {
1633       Opts.setVectorizeOnlyWhenForced(Enable);
1634     } else {
1635       return make_error<StringError>(
1636           formatv("invalid LoopVectorize parameter '{0}' ", ParamName).str(),
1637           inconvertibleErrorCode());
1638     }
1639   }
1640   return Opts;
1641 }
1642 
1643 Expected<bool> parseLoopUnswitchOptions(StringRef Params) {
1644   bool Result = false;
1645   while (!Params.empty()) {
1646     StringRef ParamName;
1647     std::tie(ParamName, Params) = Params.split(';');
1648 
1649     bool Enable = !ParamName.consume_front("no-");
1650     if (ParamName == "nontrivial") {
1651       Result = Enable;
1652     } else {
1653       return make_error<StringError>(
1654           formatv("invalid LoopUnswitch pass parameter '{0}' ", ParamName)
1655               .str(),
1656           inconvertibleErrorCode());
1657     }
1658   }
1659   return Result;
1660 }
1661 
1662 Expected<bool> parseMergedLoadStoreMotionOptions(StringRef Params) {
1663   bool Result = false;
1664   while (!Params.empty()) {
1665     StringRef ParamName;
1666     std::tie(ParamName, Params) = Params.split(';');
1667 
1668     bool Enable = !ParamName.consume_front("no-");
1669     if (ParamName == "split-footer-bb") {
1670       Result = Enable;
1671     } else {
1672       return make_error<StringError>(
1673           formatv("invalid MergedLoadStoreMotion pass parameter '{0}' ",
1674                   ParamName)
1675               .str(),
1676           inconvertibleErrorCode());
1677     }
1678   }
1679   return Result;
1680 }
1681 
1682 Expected<GVNOptions> parseGVNOptions(StringRef Params) {
1683   GVNOptions Result;
1684   while (!Params.empty()) {
1685     StringRef ParamName;
1686     std::tie(ParamName, Params) = Params.split(';');
1687 
1688     bool Enable = !ParamName.consume_front("no-");
1689     if (ParamName == "pre") {
1690       Result.setPRE(Enable);
1691     } else if (ParamName == "load-pre") {
1692       Result.setLoadPRE(Enable);
1693     } else if (ParamName == "memdep") {
1694       Result.setMemDep(Enable);
1695     } else {
1696       return make_error<StringError>(
1697           formatv("invalid GVN pass parameter '{0}' ", ParamName).str(),
1698           inconvertibleErrorCode());
1699     }
1700   }
1701   return Result;
1702 }
1703 
1704 } // namespace
1705 
1706 /// Tests whether a pass name starts with a valid prefix for a default pipeline
1707 /// alias.
1708 static bool startsWithDefaultPipelineAliasPrefix(StringRef Name) {
1709   return Name.startswith("default") || Name.startswith("thinlto") ||
1710          Name.startswith("lto");
1711 }
1712 
1713 /// Tests whether registered callbacks will accept a given pass name.
1714 ///
1715 /// When parsing a pipeline text, the type of the outermost pipeline may be
1716 /// omitted, in which case the type is automatically determined from the first
1717 /// pass name in the text. This may be a name that is handled through one of the
1718 /// callbacks. We check this through the oridinary parsing callbacks by setting
1719 /// up a dummy PassManager in order to not force the client to also handle this
1720 /// type of query.
1721 template <typename PassManagerT, typename CallbacksT>
1722 static bool callbacksAcceptPassName(StringRef Name, CallbacksT &Callbacks) {
1723   if (!Callbacks.empty()) {
1724     PassManagerT DummyPM;
1725     for (auto &CB : Callbacks)
1726       if (CB(Name, DummyPM, {}))
1727         return true;
1728   }
1729   return false;
1730 }
1731 
1732 template <typename CallbacksT>
1733 static bool isModulePassName(StringRef Name, CallbacksT &Callbacks) {
1734   // Manually handle aliases for pre-configured pipeline fragments.
1735   if (startsWithDefaultPipelineAliasPrefix(Name))
1736     return DefaultAliasRegex.match(Name);
1737 
1738   // Explicitly handle pass manager names.
1739   if (Name == "module")
1740     return true;
1741   if (Name == "cgscc")
1742     return true;
1743   if (Name == "function")
1744     return true;
1745 
1746   // Explicitly handle custom-parsed pass names.
1747   if (parseRepeatPassName(Name))
1748     return true;
1749 
1750 #define MODULE_PASS(NAME, CREATE_PASS)                                         \
1751   if (Name == NAME)                                                            \
1752     return true;
1753 #define MODULE_ANALYSIS(NAME, CREATE_PASS)                                     \
1754   if (Name == "require<" NAME ">" || Name == "invalidate<" NAME ">")           \
1755     return true;
1756 #include "PassRegistry.def"
1757 
1758   return callbacksAcceptPassName<ModulePassManager>(Name, Callbacks);
1759 }
1760 
1761 template <typename CallbacksT>
1762 static bool isCGSCCPassName(StringRef Name, CallbacksT &Callbacks) {
1763   // Explicitly handle pass manager names.
1764   if (Name == "cgscc")
1765     return true;
1766   if (Name == "function")
1767     return true;
1768 
1769   // Explicitly handle custom-parsed pass names.
1770   if (parseRepeatPassName(Name))
1771     return true;
1772   if (parseDevirtPassName(Name))
1773     return true;
1774 
1775 #define CGSCC_PASS(NAME, CREATE_PASS)                                          \
1776   if (Name == NAME)                                                            \
1777     return true;
1778 #define CGSCC_ANALYSIS(NAME, CREATE_PASS)                                      \
1779   if (Name == "require<" NAME ">" || Name == "invalidate<" NAME ">")           \
1780     return true;
1781 #include "PassRegistry.def"
1782 
1783   return callbacksAcceptPassName<CGSCCPassManager>(Name, Callbacks);
1784 }
1785 
1786 template <typename CallbacksT>
1787 static bool isFunctionPassName(StringRef Name, CallbacksT &Callbacks) {
1788   // Explicitly handle pass manager names.
1789   if (Name == "function")
1790     return true;
1791   if (Name == "loop" || Name == "loop-mssa")
1792     return true;
1793 
1794   // Explicitly handle custom-parsed pass names.
1795   if (parseRepeatPassName(Name))
1796     return true;
1797 
1798 #define FUNCTION_PASS(NAME, CREATE_PASS)                                       \
1799   if (Name == NAME)                                                            \
1800     return true;
1801 #define FUNCTION_PASS_WITH_PARAMS(NAME, CREATE_PASS, PARSER)                   \
1802   if (checkParametrizedPassName(Name, NAME))                                   \
1803     return true;
1804 #define FUNCTION_ANALYSIS(NAME, CREATE_PASS)                                   \
1805   if (Name == "require<" NAME ">" || Name == "invalidate<" NAME ">")           \
1806     return true;
1807 #include "PassRegistry.def"
1808 
1809   return callbacksAcceptPassName<FunctionPassManager>(Name, Callbacks);
1810 }
1811 
1812 template <typename CallbacksT>
1813 static bool isLoopPassName(StringRef Name, CallbacksT &Callbacks) {
1814   // Explicitly handle pass manager names.
1815   if (Name == "loop" || Name == "loop-mssa")
1816     return true;
1817 
1818   // Explicitly handle custom-parsed pass names.
1819   if (parseRepeatPassName(Name))
1820     return true;
1821 
1822 #define LOOP_PASS(NAME, CREATE_PASS)                                           \
1823   if (Name == NAME)                                                            \
1824     return true;
1825 #define LOOP_PASS_WITH_PARAMS(NAME, CREATE_PASS, PARSER)                       \
1826   if (checkParametrizedPassName(Name, NAME))                                   \
1827     return true;
1828 #define LOOP_ANALYSIS(NAME, CREATE_PASS)                                       \
1829   if (Name == "require<" NAME ">" || Name == "invalidate<" NAME ">")           \
1830     return true;
1831 #include "PassRegistry.def"
1832 
1833   return callbacksAcceptPassName<LoopPassManager>(Name, Callbacks);
1834 }
1835 
1836 Optional<std::vector<PassBuilder::PipelineElement>>
1837 PassBuilder::parsePipelineText(StringRef Text) {
1838   std::vector<PipelineElement> ResultPipeline;
1839 
1840   SmallVector<std::vector<PipelineElement> *, 4> PipelineStack = {
1841       &ResultPipeline};
1842   for (;;) {
1843     std::vector<PipelineElement> &Pipeline = *PipelineStack.back();
1844     size_t Pos = Text.find_first_of(",()");
1845     Pipeline.push_back({Text.substr(0, Pos), {}});
1846 
1847     // If we have a single terminating name, we're done.
1848     if (Pos == Text.npos)
1849       break;
1850 
1851     char Sep = Text[Pos];
1852     Text = Text.substr(Pos + 1);
1853     if (Sep == ',')
1854       // Just a name ending in a comma, continue.
1855       continue;
1856 
1857     if (Sep == '(') {
1858       // Push the inner pipeline onto the stack to continue processing.
1859       PipelineStack.push_back(&Pipeline.back().InnerPipeline);
1860       continue;
1861     }
1862 
1863     assert(Sep == ')' && "Bogus separator!");
1864     // When handling the close parenthesis, we greedily consume them to avoid
1865     // empty strings in the pipeline.
1866     do {
1867       // If we try to pop the outer pipeline we have unbalanced parentheses.
1868       if (PipelineStack.size() == 1)
1869         return None;
1870 
1871       PipelineStack.pop_back();
1872     } while (Text.consume_front(")"));
1873 
1874     // Check if we've finished parsing.
1875     if (Text.empty())
1876       break;
1877 
1878     // Otherwise, the end of an inner pipeline always has to be followed by
1879     // a comma, and then we can continue.
1880     if (!Text.consume_front(","))
1881       return None;
1882   }
1883 
1884   if (PipelineStack.size() > 1)
1885     // Unbalanced paretheses.
1886     return None;
1887 
1888   assert(PipelineStack.back() == &ResultPipeline &&
1889          "Wrong pipeline at the bottom of the stack!");
1890   return {std::move(ResultPipeline)};
1891 }
1892 
1893 Error PassBuilder::parseModulePass(ModulePassManager &MPM,
1894                                    const PipelineElement &E,
1895                                    bool VerifyEachPass, bool DebugLogging) {
1896   auto &Name = E.Name;
1897   auto &InnerPipeline = E.InnerPipeline;
1898 
1899   // First handle complex passes like the pass managers which carry pipelines.
1900   if (!InnerPipeline.empty()) {
1901     if (Name == "module") {
1902       ModulePassManager NestedMPM(DebugLogging);
1903       if (auto Err = parseModulePassPipeline(NestedMPM, InnerPipeline,
1904                                              VerifyEachPass, DebugLogging))
1905         return Err;
1906       MPM.addPass(std::move(NestedMPM));
1907       return Error::success();
1908     }
1909     if (Name == "cgscc") {
1910       CGSCCPassManager CGPM(DebugLogging);
1911       if (auto Err = parseCGSCCPassPipeline(CGPM, InnerPipeline, VerifyEachPass,
1912                                             DebugLogging))
1913         return Err;
1914       MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPM)));
1915       return Error::success();
1916     }
1917     if (Name == "function") {
1918       FunctionPassManager FPM(DebugLogging);
1919       if (auto Err = parseFunctionPassPipeline(FPM, InnerPipeline,
1920                                                VerifyEachPass, DebugLogging))
1921         return Err;
1922       MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
1923       return Error::success();
1924     }
1925     if (auto Count = parseRepeatPassName(Name)) {
1926       ModulePassManager NestedMPM(DebugLogging);
1927       if (auto Err = parseModulePassPipeline(NestedMPM, InnerPipeline,
1928                                              VerifyEachPass, DebugLogging))
1929         return Err;
1930       MPM.addPass(createRepeatedPass(*Count, std::move(NestedMPM)));
1931       return Error::success();
1932     }
1933 
1934     for (auto &C : ModulePipelineParsingCallbacks)
1935       if (C(Name, MPM, InnerPipeline))
1936         return Error::success();
1937 
1938     // Normal passes can't have pipelines.
1939     return make_error<StringError>(
1940         formatv("invalid use of '{0}' pass as module pipeline", Name).str(),
1941         inconvertibleErrorCode());
1942     ;
1943   }
1944 
1945   // Manually handle aliases for pre-configured pipeline fragments.
1946   if (startsWithDefaultPipelineAliasPrefix(Name)) {
1947     SmallVector<StringRef, 3> Matches;
1948     if (!DefaultAliasRegex.match(Name, &Matches))
1949       return make_error<StringError>(
1950           formatv("unknown default pipeline alias '{0}'", Name).str(),
1951           inconvertibleErrorCode());
1952 
1953     assert(Matches.size() == 3 && "Must capture two matched strings!");
1954 
1955     OptimizationLevel L = StringSwitch<OptimizationLevel>(Matches[2])
1956                               .Case("O0", OptimizationLevel::O0)
1957                               .Case("O1", OptimizationLevel::O1)
1958                               .Case("O2", OptimizationLevel::O2)
1959                               .Case("O3", OptimizationLevel::O3)
1960                               .Case("Os", OptimizationLevel::Os)
1961                               .Case("Oz", OptimizationLevel::Oz);
1962     if (L == OptimizationLevel::O0) {
1963       // Add instrumentation PGO passes -- at O0 we can still do PGO.
1964       if (PGOOpt && Matches[1] != "thinlto" &&
1965           (PGOOpt->Action == PGOOptions::IRInstr ||
1966            PGOOpt->Action == PGOOptions::IRUse))
1967         addPGOInstrPassesForO0(
1968             MPM, DebugLogging,
1969             /* RunProfileGen */ (PGOOpt->Action == PGOOptions::IRInstr),
1970             /* IsCS */ false, PGOOpt->ProfileFile,
1971             PGOOpt->ProfileRemappingFile);
1972 
1973       // For IR that makes use of coroutines intrinsics, coroutine passes must
1974       // be run, even at -O0.
1975       if (PTO.Coroutines) {
1976         MPM.addPass(createModuleToFunctionPassAdaptor(CoroEarlyPass()));
1977 
1978         CGSCCPassManager CGPM(DebugLogging);
1979         CGPM.addPass(CoroSplitPass());
1980         CGPM.addPass(createCGSCCToFunctionPassAdaptor(CoroElidePass()));
1981         MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPM)));
1982 
1983         MPM.addPass(createModuleToFunctionPassAdaptor(CoroCleanupPass()));
1984       }
1985 
1986       // Do nothing else at all!
1987       return Error::success();
1988     }
1989 
1990     // This is consistent with old pass manager invoked via opt, but
1991     // inconsistent with clang. Clang doesn't enable loop vectorization
1992     // but does enable slp vectorization at Oz.
1993     PTO.LoopVectorization =
1994         L.getSpeedupLevel() > 1 && L != OptimizationLevel::Oz;
1995     PTO.SLPVectorization =
1996         L.getSpeedupLevel() > 1 && L != OptimizationLevel::Oz;
1997 
1998     if (Matches[1] == "default") {
1999       MPM.addPass(buildPerModuleDefaultPipeline(L, DebugLogging));
2000     } else if (Matches[1] == "thinlto-pre-link") {
2001       MPM.addPass(buildThinLTOPreLinkDefaultPipeline(L, DebugLogging));
2002     } else if (Matches[1] == "thinlto") {
2003       MPM.addPass(buildThinLTODefaultPipeline(L, DebugLogging, nullptr));
2004     } else if (Matches[1] == "lto-pre-link") {
2005       MPM.addPass(buildLTOPreLinkDefaultPipeline(L, DebugLogging));
2006     } else {
2007       assert(Matches[1] == "lto" && "Not one of the matched options!");
2008       MPM.addPass(buildLTODefaultPipeline(L, DebugLogging, nullptr));
2009     }
2010     return Error::success();
2011   }
2012 
2013   // Finally expand the basic registered passes from the .inc file.
2014 #define MODULE_PASS(NAME, CREATE_PASS)                                         \
2015   if (Name == NAME) {                                                          \
2016     MPM.addPass(CREATE_PASS);                                                  \
2017     return Error::success();                                                   \
2018   }
2019 #define MODULE_ANALYSIS(NAME, CREATE_PASS)                                     \
2020   if (Name == "require<" NAME ">") {                                           \
2021     MPM.addPass(                                                               \
2022         RequireAnalysisPass<                                                   \
2023             std::remove_reference<decltype(CREATE_PASS)>::type, Module>());    \
2024     return Error::success();                                                   \
2025   }                                                                            \
2026   if (Name == "invalidate<" NAME ">") {                                        \
2027     MPM.addPass(InvalidateAnalysisPass<                                        \
2028                 std::remove_reference<decltype(CREATE_PASS)>::type>());        \
2029     return Error::success();                                                   \
2030   }
2031 #include "PassRegistry.def"
2032 
2033   for (auto &C : ModulePipelineParsingCallbacks)
2034     if (C(Name, MPM, InnerPipeline))
2035       return Error::success();
2036   return make_error<StringError>(
2037       formatv("unknown module pass '{0}'", Name).str(),
2038       inconvertibleErrorCode());
2039 }
2040 
2041 Error PassBuilder::parseCGSCCPass(CGSCCPassManager &CGPM,
2042                                   const PipelineElement &E, bool VerifyEachPass,
2043                                   bool DebugLogging) {
2044   auto &Name = E.Name;
2045   auto &InnerPipeline = E.InnerPipeline;
2046 
2047   // First handle complex passes like the pass managers which carry pipelines.
2048   if (!InnerPipeline.empty()) {
2049     if (Name == "cgscc") {
2050       CGSCCPassManager NestedCGPM(DebugLogging);
2051       if (auto Err = parseCGSCCPassPipeline(NestedCGPM, InnerPipeline,
2052                                             VerifyEachPass, DebugLogging))
2053         return Err;
2054       // Add the nested pass manager with the appropriate adaptor.
2055       CGPM.addPass(std::move(NestedCGPM));
2056       return Error::success();
2057     }
2058     if (Name == "function") {
2059       FunctionPassManager FPM(DebugLogging);
2060       if (auto Err = parseFunctionPassPipeline(FPM, InnerPipeline,
2061                                                VerifyEachPass, DebugLogging))
2062         return Err;
2063       // Add the nested pass manager with the appropriate adaptor.
2064       CGPM.addPass(createCGSCCToFunctionPassAdaptor(std::move(FPM)));
2065       return Error::success();
2066     }
2067     if (auto Count = parseRepeatPassName(Name)) {
2068       CGSCCPassManager NestedCGPM(DebugLogging);
2069       if (auto Err = parseCGSCCPassPipeline(NestedCGPM, InnerPipeline,
2070                                             VerifyEachPass, DebugLogging))
2071         return Err;
2072       CGPM.addPass(createRepeatedPass(*Count, std::move(NestedCGPM)));
2073       return Error::success();
2074     }
2075     if (auto MaxRepetitions = parseDevirtPassName(Name)) {
2076       CGSCCPassManager NestedCGPM(DebugLogging);
2077       if (auto Err = parseCGSCCPassPipeline(NestedCGPM, InnerPipeline,
2078                                             VerifyEachPass, DebugLogging))
2079         return Err;
2080       CGPM.addPass(
2081           createDevirtSCCRepeatedPass(std::move(NestedCGPM), *MaxRepetitions));
2082       return Error::success();
2083     }
2084 
2085     for (auto &C : CGSCCPipelineParsingCallbacks)
2086       if (C(Name, CGPM, InnerPipeline))
2087         return Error::success();
2088 
2089     // Normal passes can't have pipelines.
2090     return make_error<StringError>(
2091         formatv("invalid use of '{0}' pass as cgscc pipeline", Name).str(),
2092         inconvertibleErrorCode());
2093   }
2094 
2095 // Now expand the basic registered passes from the .inc file.
2096 #define CGSCC_PASS(NAME, CREATE_PASS)                                          \
2097   if (Name == NAME) {                                                          \
2098     CGPM.addPass(CREATE_PASS);                                                 \
2099     return Error::success();                                                   \
2100   }
2101 #define CGSCC_ANALYSIS(NAME, CREATE_PASS)                                      \
2102   if (Name == "require<" NAME ">") {                                           \
2103     CGPM.addPass(RequireAnalysisPass<                                          \
2104                  std::remove_reference<decltype(CREATE_PASS)>::type,           \
2105                  LazyCallGraph::SCC, CGSCCAnalysisManager, LazyCallGraph &,    \
2106                  CGSCCUpdateResult &>());                                      \
2107     return Error::success();                                                   \
2108   }                                                                            \
2109   if (Name == "invalidate<" NAME ">") {                                        \
2110     CGPM.addPass(InvalidateAnalysisPass<                                       \
2111                  std::remove_reference<decltype(CREATE_PASS)>::type>());       \
2112     return Error::success();                                                   \
2113   }
2114 #include "PassRegistry.def"
2115 
2116   for (auto &C : CGSCCPipelineParsingCallbacks)
2117     if (C(Name, CGPM, InnerPipeline))
2118       return Error::success();
2119   return make_error<StringError>(
2120       formatv("unknown cgscc pass '{0}'", Name).str(),
2121       inconvertibleErrorCode());
2122 }
2123 
2124 Error PassBuilder::parseFunctionPass(FunctionPassManager &FPM,
2125                                      const PipelineElement &E,
2126                                      bool VerifyEachPass, bool DebugLogging) {
2127   auto &Name = E.Name;
2128   auto &InnerPipeline = E.InnerPipeline;
2129 
2130   // First handle complex passes like the pass managers which carry pipelines.
2131   if (!InnerPipeline.empty()) {
2132     if (Name == "function") {
2133       FunctionPassManager NestedFPM(DebugLogging);
2134       if (auto Err = parseFunctionPassPipeline(NestedFPM, InnerPipeline,
2135                                                VerifyEachPass, DebugLogging))
2136         return Err;
2137       // Add the nested pass manager with the appropriate adaptor.
2138       FPM.addPass(std::move(NestedFPM));
2139       return Error::success();
2140     }
2141     if (Name == "loop" || Name == "loop-mssa") {
2142       LoopPassManager LPM(DebugLogging);
2143       if (auto Err = parseLoopPassPipeline(LPM, InnerPipeline, VerifyEachPass,
2144                                            DebugLogging))
2145         return Err;
2146       // Add the nested pass manager with the appropriate adaptor.
2147       bool UseMemorySSA = (Name == "loop-mssa");
2148       FPM.addPass(createFunctionToLoopPassAdaptor(std::move(LPM), UseMemorySSA,
2149                                                   DebugLogging));
2150       return Error::success();
2151     }
2152     if (auto Count = parseRepeatPassName(Name)) {
2153       FunctionPassManager NestedFPM(DebugLogging);
2154       if (auto Err = parseFunctionPassPipeline(NestedFPM, InnerPipeline,
2155                                                VerifyEachPass, DebugLogging))
2156         return Err;
2157       FPM.addPass(createRepeatedPass(*Count, std::move(NestedFPM)));
2158       return Error::success();
2159     }
2160 
2161     for (auto &C : FunctionPipelineParsingCallbacks)
2162       if (C(Name, FPM, InnerPipeline))
2163         return Error::success();
2164 
2165     // Normal passes can't have pipelines.
2166     return make_error<StringError>(
2167         formatv("invalid use of '{0}' pass as function pipeline", Name).str(),
2168         inconvertibleErrorCode());
2169   }
2170 
2171 // Now expand the basic registered passes from the .inc file.
2172 #define FUNCTION_PASS(NAME, CREATE_PASS)                                       \
2173   if (Name == NAME) {                                                          \
2174     FPM.addPass(CREATE_PASS);                                                  \
2175     return Error::success();                                                   \
2176   }
2177 #define FUNCTION_PASS_WITH_PARAMS(NAME, CREATE_PASS, PARSER)                   \
2178   if (checkParametrizedPassName(Name, NAME)) {                                 \
2179     auto Params = parsePassParameters(PARSER, Name, NAME);                     \
2180     if (!Params)                                                               \
2181       return Params.takeError();                                               \
2182     FPM.addPass(CREATE_PASS(Params.get()));                                    \
2183     return Error::success();                                                   \
2184   }
2185 #define FUNCTION_ANALYSIS(NAME, CREATE_PASS)                                   \
2186   if (Name == "require<" NAME ">") {                                           \
2187     FPM.addPass(                                                               \
2188         RequireAnalysisPass<                                                   \
2189             std::remove_reference<decltype(CREATE_PASS)>::type, Function>());  \
2190     return Error::success();                                                   \
2191   }                                                                            \
2192   if (Name == "invalidate<" NAME ">") {                                        \
2193     FPM.addPass(InvalidateAnalysisPass<                                        \
2194                 std::remove_reference<decltype(CREATE_PASS)>::type>());        \
2195     return Error::success();                                                   \
2196   }
2197 #include "PassRegistry.def"
2198 
2199   for (auto &C : FunctionPipelineParsingCallbacks)
2200     if (C(Name, FPM, InnerPipeline))
2201       return Error::success();
2202   return make_error<StringError>(
2203       formatv("unknown function pass '{0}'", Name).str(),
2204       inconvertibleErrorCode());
2205 }
2206 
2207 Error PassBuilder::parseLoopPass(LoopPassManager &LPM, const PipelineElement &E,
2208                                  bool VerifyEachPass, bool DebugLogging) {
2209   StringRef Name = E.Name;
2210   auto &InnerPipeline = E.InnerPipeline;
2211 
2212   // First handle complex passes like the pass managers which carry pipelines.
2213   if (!InnerPipeline.empty()) {
2214     if (Name == "loop") {
2215       LoopPassManager NestedLPM(DebugLogging);
2216       if (auto Err = parseLoopPassPipeline(NestedLPM, InnerPipeline,
2217                                            VerifyEachPass, DebugLogging))
2218         return Err;
2219       // Add the nested pass manager with the appropriate adaptor.
2220       LPM.addPass(std::move(NestedLPM));
2221       return Error::success();
2222     }
2223     if (auto Count = parseRepeatPassName(Name)) {
2224       LoopPassManager NestedLPM(DebugLogging);
2225       if (auto Err = parseLoopPassPipeline(NestedLPM, InnerPipeline,
2226                                            VerifyEachPass, DebugLogging))
2227         return Err;
2228       LPM.addPass(createRepeatedPass(*Count, std::move(NestedLPM)));
2229       return Error::success();
2230     }
2231 
2232     for (auto &C : LoopPipelineParsingCallbacks)
2233       if (C(Name, LPM, InnerPipeline))
2234         return Error::success();
2235 
2236     // Normal passes can't have pipelines.
2237     return make_error<StringError>(
2238         formatv("invalid use of '{0}' pass as loop pipeline", Name).str(),
2239         inconvertibleErrorCode());
2240   }
2241 
2242 // Now expand the basic registered passes from the .inc file.
2243 #define LOOP_PASS(NAME, CREATE_PASS)                                           \
2244   if (Name == NAME) {                                                          \
2245     LPM.addPass(CREATE_PASS);                                                  \
2246     return Error::success();                                                   \
2247   }
2248 #define LOOP_PASS_WITH_PARAMS(NAME, CREATE_PASS, PARSER)                       \
2249   if (checkParametrizedPassName(Name, NAME)) {                                 \
2250     auto Params = parsePassParameters(PARSER, Name, NAME);                     \
2251     if (!Params)                                                               \
2252       return Params.takeError();                                               \
2253     LPM.addPass(CREATE_PASS(Params.get()));                                    \
2254     return Error::success();                                                   \
2255   }
2256 #define LOOP_ANALYSIS(NAME, CREATE_PASS)                                       \
2257   if (Name == "require<" NAME ">") {                                           \
2258     LPM.addPass(RequireAnalysisPass<                                           \
2259                 std::remove_reference<decltype(CREATE_PASS)>::type, Loop,      \
2260                 LoopAnalysisManager, LoopStandardAnalysisResults &,            \
2261                 LPMUpdater &>());                                              \
2262     return Error::success();                                                   \
2263   }                                                                            \
2264   if (Name == "invalidate<" NAME ">") {                                        \
2265     LPM.addPass(InvalidateAnalysisPass<                                        \
2266                 std::remove_reference<decltype(CREATE_PASS)>::type>());        \
2267     return Error::success();                                                   \
2268   }
2269 #include "PassRegistry.def"
2270 
2271   for (auto &C : LoopPipelineParsingCallbacks)
2272     if (C(Name, LPM, InnerPipeline))
2273       return Error::success();
2274   return make_error<StringError>(formatv("unknown loop pass '{0}'", Name).str(),
2275                                  inconvertibleErrorCode());
2276 }
2277 
2278 bool PassBuilder::parseAAPassName(AAManager &AA, StringRef Name) {
2279 #define MODULE_ALIAS_ANALYSIS(NAME, CREATE_PASS)                               \
2280   if (Name == NAME) {                                                          \
2281     AA.registerModuleAnalysis<                                                 \
2282         std::remove_reference<decltype(CREATE_PASS)>::type>();                 \
2283     return true;                                                               \
2284   }
2285 #define FUNCTION_ALIAS_ANALYSIS(NAME, CREATE_PASS)                             \
2286   if (Name == NAME) {                                                          \
2287     AA.registerFunctionAnalysis<                                               \
2288         std::remove_reference<decltype(CREATE_PASS)>::type>();                 \
2289     return true;                                                               \
2290   }
2291 #include "PassRegistry.def"
2292 
2293   for (auto &C : AAParsingCallbacks)
2294     if (C(Name, AA))
2295       return true;
2296   return false;
2297 }
2298 
2299 Error PassBuilder::parseLoopPassPipeline(LoopPassManager &LPM,
2300                                          ArrayRef<PipelineElement> Pipeline,
2301                                          bool VerifyEachPass,
2302                                          bool DebugLogging) {
2303   for (const auto &Element : Pipeline) {
2304     if (auto Err = parseLoopPass(LPM, Element, VerifyEachPass, DebugLogging))
2305       return Err;
2306     // FIXME: No verifier support for Loop passes!
2307   }
2308   return Error::success();
2309 }
2310 
2311 Error PassBuilder::parseFunctionPassPipeline(FunctionPassManager &FPM,
2312                                              ArrayRef<PipelineElement> Pipeline,
2313                                              bool VerifyEachPass,
2314                                              bool DebugLogging) {
2315   for (const auto &Element : Pipeline) {
2316     if (auto Err =
2317             parseFunctionPass(FPM, Element, VerifyEachPass, DebugLogging))
2318       return Err;
2319     if (VerifyEachPass)
2320       FPM.addPass(VerifierPass());
2321   }
2322   return Error::success();
2323 }
2324 
2325 Error PassBuilder::parseCGSCCPassPipeline(CGSCCPassManager &CGPM,
2326                                           ArrayRef<PipelineElement> Pipeline,
2327                                           bool VerifyEachPass,
2328                                           bool DebugLogging) {
2329   for (const auto &Element : Pipeline) {
2330     if (auto Err = parseCGSCCPass(CGPM, Element, VerifyEachPass, DebugLogging))
2331       return Err;
2332     // FIXME: No verifier support for CGSCC passes!
2333   }
2334   return Error::success();
2335 }
2336 
2337 void PassBuilder::crossRegisterProxies(LoopAnalysisManager &LAM,
2338                                        FunctionAnalysisManager &FAM,
2339                                        CGSCCAnalysisManager &CGAM,
2340                                        ModuleAnalysisManager &MAM) {
2341   MAM.registerPass([&] { return FunctionAnalysisManagerModuleProxy(FAM); });
2342   MAM.registerPass([&] { return CGSCCAnalysisManagerModuleProxy(CGAM); });
2343   CGAM.registerPass([&] { return ModuleAnalysisManagerCGSCCProxy(MAM); });
2344   FAM.registerPass([&] { return CGSCCAnalysisManagerFunctionProxy(CGAM); });
2345   FAM.registerPass([&] { return ModuleAnalysisManagerFunctionProxy(MAM); });
2346   FAM.registerPass([&] { return LoopAnalysisManagerFunctionProxy(LAM); });
2347   LAM.registerPass([&] { return FunctionAnalysisManagerLoopProxy(FAM); });
2348 }
2349 
2350 Error PassBuilder::parseModulePassPipeline(ModulePassManager &MPM,
2351                                            ArrayRef<PipelineElement> Pipeline,
2352                                            bool VerifyEachPass,
2353                                            bool DebugLogging) {
2354   for (const auto &Element : Pipeline) {
2355     if (auto Err = parseModulePass(MPM, Element, VerifyEachPass, DebugLogging))
2356       return Err;
2357     if (VerifyEachPass)
2358       MPM.addPass(VerifierPass());
2359   }
2360   return Error::success();
2361 }
2362 
2363 // Primary pass pipeline description parsing routine for a \c ModulePassManager
2364 // FIXME: Should this routine accept a TargetMachine or require the caller to
2365 // pre-populate the analysis managers with target-specific stuff?
2366 Error PassBuilder::parsePassPipeline(ModulePassManager &MPM,
2367                                      StringRef PipelineText,
2368                                      bool VerifyEachPass, bool DebugLogging) {
2369   auto Pipeline = parsePipelineText(PipelineText);
2370   if (!Pipeline || Pipeline->empty())
2371     return make_error<StringError>(
2372         formatv("invalid pipeline '{0}'", PipelineText).str(),
2373         inconvertibleErrorCode());
2374 
2375   // If the first name isn't at the module layer, wrap the pipeline up
2376   // automatically.
2377   StringRef FirstName = Pipeline->front().Name;
2378 
2379   if (!isModulePassName(FirstName, ModulePipelineParsingCallbacks)) {
2380     if (isCGSCCPassName(FirstName, CGSCCPipelineParsingCallbacks)) {
2381       Pipeline = {{"cgscc", std::move(*Pipeline)}};
2382     } else if (isFunctionPassName(FirstName,
2383                                   FunctionPipelineParsingCallbacks)) {
2384       Pipeline = {{"function", std::move(*Pipeline)}};
2385     } else if (isLoopPassName(FirstName, LoopPipelineParsingCallbacks)) {
2386       Pipeline = {{"function", {{"loop", std::move(*Pipeline)}}}};
2387     } else {
2388       for (auto &C : TopLevelPipelineParsingCallbacks)
2389         if (C(MPM, *Pipeline, VerifyEachPass, DebugLogging))
2390           return Error::success();
2391 
2392       // Unknown pass or pipeline name!
2393       auto &InnerPipeline = Pipeline->front().InnerPipeline;
2394       return make_error<StringError>(
2395           formatv("unknown {0} name '{1}'",
2396                   (InnerPipeline.empty() ? "pass" : "pipeline"), FirstName)
2397               .str(),
2398           inconvertibleErrorCode());
2399     }
2400   }
2401 
2402   if (auto Err =
2403           parseModulePassPipeline(MPM, *Pipeline, VerifyEachPass, DebugLogging))
2404     return Err;
2405   return Error::success();
2406 }
2407 
2408 // Primary pass pipeline description parsing routine for a \c CGSCCPassManager
2409 Error PassBuilder::parsePassPipeline(CGSCCPassManager &CGPM,
2410                                      StringRef PipelineText,
2411                                      bool VerifyEachPass, bool DebugLogging) {
2412   auto Pipeline = parsePipelineText(PipelineText);
2413   if (!Pipeline || Pipeline->empty())
2414     return make_error<StringError>(
2415         formatv("invalid pipeline '{0}'", PipelineText).str(),
2416         inconvertibleErrorCode());
2417 
2418   StringRef FirstName = Pipeline->front().Name;
2419   if (!isCGSCCPassName(FirstName, CGSCCPipelineParsingCallbacks))
2420     return make_error<StringError>(
2421         formatv("unknown cgscc pass '{0}' in pipeline '{1}'", FirstName,
2422                 PipelineText)
2423             .str(),
2424         inconvertibleErrorCode());
2425 
2426   if (auto Err =
2427           parseCGSCCPassPipeline(CGPM, *Pipeline, VerifyEachPass, DebugLogging))
2428     return Err;
2429   return Error::success();
2430 }
2431 
2432 // Primary pass pipeline description parsing routine for a \c
2433 // FunctionPassManager
2434 Error PassBuilder::parsePassPipeline(FunctionPassManager &FPM,
2435                                      StringRef PipelineText,
2436                                      bool VerifyEachPass, bool DebugLogging) {
2437   auto Pipeline = parsePipelineText(PipelineText);
2438   if (!Pipeline || Pipeline->empty())
2439     return make_error<StringError>(
2440         formatv("invalid pipeline '{0}'", PipelineText).str(),
2441         inconvertibleErrorCode());
2442 
2443   StringRef FirstName = Pipeline->front().Name;
2444   if (!isFunctionPassName(FirstName, FunctionPipelineParsingCallbacks))
2445     return make_error<StringError>(
2446         formatv("unknown function pass '{0}' in pipeline '{1}'", FirstName,
2447                 PipelineText)
2448             .str(),
2449         inconvertibleErrorCode());
2450 
2451   if (auto Err = parseFunctionPassPipeline(FPM, *Pipeline, VerifyEachPass,
2452                                            DebugLogging))
2453     return Err;
2454   return Error::success();
2455 }
2456 
2457 // Primary pass pipeline description parsing routine for a \c LoopPassManager
2458 Error PassBuilder::parsePassPipeline(LoopPassManager &CGPM,
2459                                      StringRef PipelineText,
2460                                      bool VerifyEachPass, bool DebugLogging) {
2461   auto Pipeline = parsePipelineText(PipelineText);
2462   if (!Pipeline || Pipeline->empty())
2463     return make_error<StringError>(
2464         formatv("invalid pipeline '{0}'", PipelineText).str(),
2465         inconvertibleErrorCode());
2466 
2467   if (auto Err =
2468           parseLoopPassPipeline(CGPM, *Pipeline, VerifyEachPass, DebugLogging))
2469     return Err;
2470 
2471   return Error::success();
2472 }
2473 
2474 Error PassBuilder::parseAAPipeline(AAManager &AA, StringRef PipelineText) {
2475   // If the pipeline just consists of the word 'default' just replace the AA
2476   // manager with our default one.
2477   if (PipelineText == "default") {
2478     AA = buildDefaultAAPipeline();
2479     return Error::success();
2480   }
2481 
2482   while (!PipelineText.empty()) {
2483     StringRef Name;
2484     std::tie(Name, PipelineText) = PipelineText.split(',');
2485     if (!parseAAPassName(AA, Name))
2486       return make_error<StringError>(
2487           formatv("unknown alias analysis name '{0}'", Name).str(),
2488           inconvertibleErrorCode());
2489   }
2490 
2491   return Error::success();
2492 }
2493