1 //===- InlineAdvisor.cpp - analysis pass implementation -------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements InlineAdvisorAnalysis and DefaultInlineAdvisor, and
10 // related types.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "llvm/Analysis/InlineAdvisor.h"
15 #include "llvm/ADT/Statistic.h"
16 #include "llvm/Analysis/AssumptionCache.h"
17 #include "llvm/Analysis/InlineCost.h"
18 #include "llvm/Analysis/OptimizationRemarkEmitter.h"
19 #include "llvm/Analysis/ProfileSummaryInfo.h"
20 #include "llvm/Analysis/ReplayInlineAdvisor.h"
21 #include "llvm/Analysis/TargetLibraryInfo.h"
22 #include "llvm/Analysis/TargetTransformInfo.h"
23 #include "llvm/Analysis/Utils/ImportedFunctionsInliningStatistics.h"
24 #include "llvm/IR/DebugInfoMetadata.h"
25 #include "llvm/IR/PassManager.h"
26 #include "llvm/Support/CommandLine.h"
27 #include "llvm/Support/raw_ostream.h"
28
29 using namespace llvm;
30 #define DEBUG_TYPE "inline"
31 #ifdef LLVM_HAVE_TF_AOT_INLINERSIZEMODEL
32 #define LLVM_HAVE_TF_AOT
33 #endif
34
35 // This weirdly named statistic tracks the number of times that, when attempting
36 // to inline a function A into B, we analyze the callers of B in order to see
37 // if those would be more profitable and blocked inline steps.
38 STATISTIC(NumCallerCallersAnalyzed, "Number of caller-callers analyzed");
39
40 /// Flag to add inline messages as callsite attributes 'inline-remark'.
41 static cl::opt<bool>
42 InlineRemarkAttribute("inline-remark-attribute", cl::init(false),
43 cl::Hidden,
44 cl::desc("Enable adding inline-remark attribute to"
45 " callsites processed by inliner but decided"
46 " to be not inlined"));
47
48 static cl::opt<bool> EnableInlineDeferral("inline-deferral", cl::init(false),
49 cl::Hidden,
50 cl::desc("Enable deferred inlining"));
51
52 // An integer used to limit the cost of inline deferral. The default negative
53 // number tells shouldBeDeferred to only take the secondary cost into account.
54 static cl::opt<int>
55 InlineDeferralScale("inline-deferral-scale",
56 cl::desc("Scale to limit the cost of inline deferral"),
57 cl::init(2), cl::Hidden);
58
59 static cl::opt<bool>
60 AnnotateInlinePhase("annotate-inline-phase", cl::Hidden, cl::init(false),
61 cl::desc("If true, annotate inline advisor remarks "
62 "with LTO and pass information."));
63
64 namespace llvm {
65 extern cl::opt<InlinerFunctionImportStatsOpts> InlinerFunctionImportStats;
66 }
67
68 namespace {
69 using namespace llvm::ore;
70 class MandatoryInlineAdvice : public InlineAdvice {
71 public:
MandatoryInlineAdvice(InlineAdvisor * Advisor,CallBase & CB,OptimizationRemarkEmitter & ORE,bool IsInliningMandatory)72 MandatoryInlineAdvice(InlineAdvisor *Advisor, CallBase &CB,
73 OptimizationRemarkEmitter &ORE,
74 bool IsInliningMandatory)
75 : InlineAdvice(Advisor, CB, ORE, IsInliningMandatory) {}
76
77 private:
recordInliningWithCalleeDeletedImpl()78 void recordInliningWithCalleeDeletedImpl() override { recordInliningImpl(); }
79
recordInliningImpl()80 void recordInliningImpl() override {
81 if (IsInliningRecommended)
82 emitInlinedInto(ORE, DLoc, Block, *Callee, *Caller, IsInliningRecommended,
83 [&](OptimizationRemark &Remark) {
84 Remark << ": always inline attribute";
85 });
86 }
87
recordUnsuccessfulInliningImpl(const InlineResult & Result)88 void recordUnsuccessfulInliningImpl(const InlineResult &Result) override {
89 if (IsInliningRecommended)
90 ORE.emit([&]() {
91 return OptimizationRemarkMissed(Advisor->getAnnotatedInlinePassName(),
92 "NotInlined", DLoc, Block)
93 << "'" << NV("Callee", Callee) << "' is not AlwaysInline into '"
94 << NV("Caller", Caller)
95 << "': " << NV("Reason", Result.getFailureReason());
96 });
97 }
98
recordUnattemptedInliningImpl()99 void recordUnattemptedInliningImpl() override {
100 assert(!IsInliningRecommended && "Expected to attempt inlining");
101 }
102 };
103 } // namespace
104
recordUnsuccessfulInliningImpl(const InlineResult & Result)105 void DefaultInlineAdvice::recordUnsuccessfulInliningImpl(
106 const InlineResult &Result) {
107 using namespace ore;
108 llvm::setInlineRemark(*OriginalCB, std::string(Result.getFailureReason()) +
109 "; " + inlineCostStr(*OIC));
110 ORE.emit([&]() {
111 return OptimizationRemarkMissed(Advisor->getAnnotatedInlinePassName(),
112 "NotInlined", DLoc, Block)
113 << "'" << NV("Callee", Callee) << "' is not inlined into '"
114 << NV("Caller", Caller)
115 << "': " << NV("Reason", Result.getFailureReason());
116 });
117 }
118
recordInliningWithCalleeDeletedImpl()119 void DefaultInlineAdvice::recordInliningWithCalleeDeletedImpl() {
120 if (EmitRemarks)
121 emitInlinedIntoBasedOnCost(ORE, DLoc, Block, *Callee, *Caller, *OIC,
122 /* ForProfileContext= */ false,
123 Advisor->getAnnotatedInlinePassName());
124 }
125
recordInliningImpl()126 void DefaultInlineAdvice::recordInliningImpl() {
127 if (EmitRemarks)
128 emitInlinedIntoBasedOnCost(ORE, DLoc, Block, *Callee, *Caller, *OIC,
129 /* ForProfileContext= */ false,
130 Advisor->getAnnotatedInlinePassName());
131 }
132
getDefaultInlineAdvice(CallBase & CB,FunctionAnalysisManager & FAM,const InlineParams & Params)133 std::optional<llvm::InlineCost> static getDefaultInlineAdvice(
134 CallBase &CB, FunctionAnalysisManager &FAM, const InlineParams &Params) {
135 Function &Caller = *CB.getCaller();
136 ProfileSummaryInfo *PSI =
137 FAM.getResult<ModuleAnalysisManagerFunctionProxy>(Caller)
138 .getCachedResult<ProfileSummaryAnalysis>(
139 *CB.getParent()->getParent()->getParent());
140
141 auto &ORE = FAM.getResult<OptimizationRemarkEmitterAnalysis>(Caller);
142 auto GetAssumptionCache = [&](Function &F) -> AssumptionCache & {
143 return FAM.getResult<AssumptionAnalysis>(F);
144 };
145 auto GetBFI = [&](Function &F) -> BlockFrequencyInfo & {
146 return FAM.getResult<BlockFrequencyAnalysis>(F);
147 };
148 auto GetTLI = [&](Function &F) -> const TargetLibraryInfo & {
149 return FAM.getResult<TargetLibraryAnalysis>(F);
150 };
151
152 auto GetInlineCost = [&](CallBase &CB) {
153 Function &Callee = *CB.getCalledFunction();
154 auto &CalleeTTI = FAM.getResult<TargetIRAnalysis>(Callee);
155 bool RemarksEnabled =
156 Callee.getContext().getDiagHandlerPtr()->isMissedOptRemarkEnabled(
157 DEBUG_TYPE);
158 return getInlineCost(CB, Params, CalleeTTI, GetAssumptionCache, GetTLI,
159 GetBFI, PSI, RemarksEnabled ? &ORE : nullptr);
160 };
161 return llvm::shouldInline(
162 CB, GetInlineCost, ORE,
163 Params.EnableDeferral.value_or(EnableInlineDeferral));
164 }
165
166 std::unique_ptr<InlineAdvice>
getAdviceImpl(CallBase & CB)167 DefaultInlineAdvisor::getAdviceImpl(CallBase &CB) {
168 auto OIC = getDefaultInlineAdvice(CB, FAM, Params);
169 return std::make_unique<DefaultInlineAdvice>(
170 this, CB, OIC,
171 FAM.getResult<OptimizationRemarkEmitterAnalysis>(*CB.getCaller()));
172 }
173
InlineAdvice(InlineAdvisor * Advisor,CallBase & CB,OptimizationRemarkEmitter & ORE,bool IsInliningRecommended)174 InlineAdvice::InlineAdvice(InlineAdvisor *Advisor, CallBase &CB,
175 OptimizationRemarkEmitter &ORE,
176 bool IsInliningRecommended)
177 : Advisor(Advisor), Caller(CB.getCaller()), Callee(CB.getCalledFunction()),
178 DLoc(CB.getDebugLoc()), Block(CB.getParent()), ORE(ORE),
179 IsInliningRecommended(IsInliningRecommended) {}
180
recordInlineStatsIfNeeded()181 void InlineAdvice::recordInlineStatsIfNeeded() {
182 if (Advisor->ImportedFunctionsStats)
183 Advisor->ImportedFunctionsStats->recordInline(*Caller, *Callee);
184 }
185
recordInlining()186 void InlineAdvice::recordInlining() {
187 markRecorded();
188 recordInlineStatsIfNeeded();
189 recordInliningImpl();
190 }
191
recordInliningWithCalleeDeleted()192 void InlineAdvice::recordInliningWithCalleeDeleted() {
193 markRecorded();
194 recordInlineStatsIfNeeded();
195 recordInliningWithCalleeDeletedImpl();
196 }
197
198 AnalysisKey InlineAdvisorAnalysis::Key;
199 AnalysisKey PluginInlineAdvisorAnalysis::Key;
200 bool PluginInlineAdvisorAnalysis::HasBeenRegistered = false;
201
tryCreate(InlineParams Params,InliningAdvisorMode Mode,const ReplayInlinerSettings & ReplaySettings,InlineContext IC)202 bool InlineAdvisorAnalysis::Result::tryCreate(
203 InlineParams Params, InliningAdvisorMode Mode,
204 const ReplayInlinerSettings &ReplaySettings, InlineContext IC) {
205 auto &FAM = MAM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
206 if (PluginInlineAdvisorAnalysis::HasBeenRegistered) {
207 auto &DA = MAM.getResult<PluginInlineAdvisorAnalysis>(M);
208 Advisor.reset(DA.Factory(M, FAM, Params, IC));
209 return !!Advisor;
210 }
211 switch (Mode) {
212 case InliningAdvisorMode::Default:
213 LLVM_DEBUG(dbgs() << "Using default inliner heuristic.\n");
214 Advisor.reset(new DefaultInlineAdvisor(M, FAM, Params, IC));
215 // Restrict replay to default advisor, ML advisors are stateful so
216 // replay will need augmentations to interleave with them correctly.
217 if (!ReplaySettings.ReplayFile.empty()) {
218 Advisor = llvm::getReplayInlineAdvisor(M, FAM, M.getContext(),
219 std::move(Advisor), ReplaySettings,
220 /* EmitRemarks =*/true, IC);
221 }
222 break;
223 case InliningAdvisorMode::Development:
224 #ifdef LLVM_HAVE_TFLITE
225 LLVM_DEBUG(dbgs() << "Using development-mode inliner policy.\n");
226 Advisor =
227 llvm::getDevelopmentModeAdvisor(M, MAM, [&FAM, Params](CallBase &CB) {
228 auto OIC = getDefaultInlineAdvice(CB, FAM, Params);
229 return OIC.has_value();
230 });
231 #endif
232 break;
233 case InliningAdvisorMode::Release:
234 #ifdef LLVM_HAVE_TF_AOT
235 LLVM_DEBUG(dbgs() << "Using release-mode inliner policy.\n");
236 Advisor = llvm::getReleaseModeAdvisor(M, MAM);
237 #endif
238 break;
239 }
240
241 return !!Advisor;
242 }
243
244 /// Return true if inlining of CB can block the caller from being
245 /// inlined which is proved to be more beneficial. \p IC is the
246 /// estimated inline cost associated with callsite \p CB.
247 /// \p TotalSecondaryCost will be set to the estimated cost of inlining the
248 /// caller if \p CB is suppressed for inlining.
249 static bool
shouldBeDeferred(Function * Caller,InlineCost IC,int & TotalSecondaryCost,function_ref<InlineCost (CallBase & CB)> GetInlineCost)250 shouldBeDeferred(Function *Caller, InlineCost IC, int &TotalSecondaryCost,
251 function_ref<InlineCost(CallBase &CB)> GetInlineCost) {
252 // For now we only handle local or inline functions.
253 if (!Caller->hasLocalLinkage() && !Caller->hasLinkOnceODRLinkage())
254 return false;
255 // If the cost of inlining CB is non-positive, it is not going to prevent the
256 // caller from being inlined into its callers and hence we don't need to
257 // defer.
258 if (IC.getCost() <= 0)
259 return false;
260 // Try to detect the case where the current inlining candidate caller (call
261 // it B) is a static or linkonce-ODR function and is an inlining candidate
262 // elsewhere, and the current candidate callee (call it C) is large enough
263 // that inlining it into B would make B too big to inline later. In these
264 // circumstances it may be best not to inline C into B, but to inline B into
265 // its callers.
266 //
267 // This only applies to static and linkonce-ODR functions because those are
268 // expected to be available for inlining in the translation units where they
269 // are used. Thus we will always have the opportunity to make local inlining
270 // decisions. Importantly the linkonce-ODR linkage covers inline functions
271 // and templates in C++.
272 //
273 // FIXME: All of this logic should be sunk into getInlineCost. It relies on
274 // the internal implementation of the inline cost metrics rather than
275 // treating them as truly abstract units etc.
276 TotalSecondaryCost = 0;
277 // The candidate cost to be imposed upon the current function.
278 int CandidateCost = IC.getCost() - 1;
279 // If the caller has local linkage and can be inlined to all its callers, we
280 // can apply a huge negative bonus to TotalSecondaryCost.
281 bool ApplyLastCallBonus = Caller->hasLocalLinkage() && !Caller->hasOneUse();
282 // This bool tracks what happens if we DO inline C into B.
283 bool InliningPreventsSomeOuterInline = false;
284 unsigned NumCallerUsers = 0;
285 for (User *U : Caller->users()) {
286 CallBase *CS2 = dyn_cast<CallBase>(U);
287
288 // If this isn't a call to Caller (it could be some other sort
289 // of reference) skip it. Such references will prevent the caller
290 // from being removed.
291 if (!CS2 || CS2->getCalledFunction() != Caller) {
292 ApplyLastCallBonus = false;
293 continue;
294 }
295
296 InlineCost IC2 = GetInlineCost(*CS2);
297 ++NumCallerCallersAnalyzed;
298 if (!IC2) {
299 ApplyLastCallBonus = false;
300 continue;
301 }
302 if (IC2.isAlways())
303 continue;
304
305 // See if inlining of the original callsite would erase the cost delta of
306 // this callsite. We subtract off the penalty for the call instruction,
307 // which we would be deleting.
308 if (IC2.getCostDelta() <= CandidateCost) {
309 InliningPreventsSomeOuterInline = true;
310 TotalSecondaryCost += IC2.getCost();
311 NumCallerUsers++;
312 }
313 }
314
315 if (!InliningPreventsSomeOuterInline)
316 return false;
317
318 // If all outer calls to Caller would get inlined, the cost for the last
319 // one is set very low by getInlineCost, in anticipation that Caller will
320 // be removed entirely. We did not account for this above unless there
321 // is only one caller of Caller.
322 if (ApplyLastCallBonus)
323 TotalSecondaryCost -= InlineConstants::LastCallToStaticBonus;
324
325 // If InlineDeferralScale is negative, then ignore the cost of primary
326 // inlining -- IC.getCost() multiplied by the number of callers to Caller.
327 if (InlineDeferralScale < 0)
328 return TotalSecondaryCost < IC.getCost();
329
330 int TotalCost = TotalSecondaryCost + IC.getCost() * NumCallerUsers;
331 int Allowance = IC.getCost() * InlineDeferralScale;
332 return TotalCost < Allowance;
333 }
334
335 namespace llvm {
operator <<(raw_ostream & R,const ore::NV & Arg)336 static raw_ostream &operator<<(raw_ostream &R, const ore::NV &Arg) {
337 return R << Arg.Val;
338 }
339
340 template <class RemarkT>
operator <<(RemarkT && R,const InlineCost & IC)341 RemarkT &operator<<(RemarkT &&R, const InlineCost &IC) {
342 using namespace ore;
343 if (IC.isAlways()) {
344 R << "(cost=always)";
345 } else if (IC.isNever()) {
346 R << "(cost=never)";
347 } else {
348 R << "(cost=" << ore::NV("Cost", IC.getCost())
349 << ", threshold=" << ore::NV("Threshold", IC.getThreshold()) << ")";
350 }
351 if (const char *Reason = IC.getReason())
352 R << ": " << ore::NV("Reason", Reason);
353 return R;
354 }
355 } // namespace llvm
356
inlineCostStr(const InlineCost & IC)357 std::string llvm::inlineCostStr(const InlineCost &IC) {
358 std::string Buffer;
359 raw_string_ostream Remark(Buffer);
360 Remark << IC;
361 return Remark.str();
362 }
363
setInlineRemark(CallBase & CB,StringRef Message)364 void llvm::setInlineRemark(CallBase &CB, StringRef Message) {
365 if (!InlineRemarkAttribute)
366 return;
367
368 Attribute Attr = Attribute::get(CB.getContext(), "inline-remark", Message);
369 CB.addFnAttr(Attr);
370 }
371
372 /// Return the cost only if the inliner should attempt to inline at the given
373 /// CallSite. If we return the cost, we will emit an optimisation remark later
374 /// using that cost, so we won't do so from this function. Return std::nullopt
375 /// if inlining should not be attempted.
376 std::optional<InlineCost>
shouldInline(CallBase & CB,function_ref<InlineCost (CallBase & CB)> GetInlineCost,OptimizationRemarkEmitter & ORE,bool EnableDeferral)377 llvm::shouldInline(CallBase &CB,
378 function_ref<InlineCost(CallBase &CB)> GetInlineCost,
379 OptimizationRemarkEmitter &ORE, bool EnableDeferral) {
380 using namespace ore;
381
382 InlineCost IC = GetInlineCost(CB);
383 Instruction *Call = &CB;
384 Function *Callee = CB.getCalledFunction();
385 Function *Caller = CB.getCaller();
386
387 if (IC.isAlways()) {
388 LLVM_DEBUG(dbgs() << " Inlining " << inlineCostStr(IC)
389 << ", Call: " << CB << "\n");
390 return IC;
391 }
392
393 if (!IC) {
394 LLVM_DEBUG(dbgs() << " NOT Inlining " << inlineCostStr(IC)
395 << ", Call: " << CB << "\n");
396 if (IC.isNever()) {
397 ORE.emit([&]() {
398 return OptimizationRemarkMissed(DEBUG_TYPE, "NeverInline", Call)
399 << "'" << NV("Callee", Callee) << "' not inlined into '"
400 << NV("Caller", Caller)
401 << "' because it should never be inlined " << IC;
402 });
403 } else {
404 ORE.emit([&]() {
405 return OptimizationRemarkMissed(DEBUG_TYPE, "TooCostly", Call)
406 << "'" << NV("Callee", Callee) << "' not inlined into '"
407 << NV("Caller", Caller) << "' because too costly to inline "
408 << IC;
409 });
410 }
411 setInlineRemark(CB, inlineCostStr(IC));
412 return std::nullopt;
413 }
414
415 int TotalSecondaryCost = 0;
416 if (EnableDeferral &&
417 shouldBeDeferred(Caller, IC, TotalSecondaryCost, GetInlineCost)) {
418 LLVM_DEBUG(dbgs() << " NOT Inlining: " << CB
419 << " Cost = " << IC.getCost()
420 << ", outer Cost = " << TotalSecondaryCost << '\n');
421 ORE.emit([&]() {
422 return OptimizationRemarkMissed(DEBUG_TYPE, "IncreaseCostInOtherContexts",
423 Call)
424 << "Not inlining. Cost of inlining '" << NV("Callee", Callee)
425 << "' increases the cost of inlining '" << NV("Caller", Caller)
426 << "' in other contexts";
427 });
428 setInlineRemark(CB, "deferred");
429 return std::nullopt;
430 }
431
432 LLVM_DEBUG(dbgs() << " Inlining " << inlineCostStr(IC) << ", Call: " << CB
433 << '\n');
434 return IC;
435 }
436
formatCallSiteLocation(DebugLoc DLoc,const CallSiteFormat & Format)437 std::string llvm::formatCallSiteLocation(DebugLoc DLoc,
438 const CallSiteFormat &Format) {
439 std::string Buffer;
440 raw_string_ostream CallSiteLoc(Buffer);
441 bool First = true;
442 for (DILocation *DIL = DLoc.get(); DIL; DIL = DIL->getInlinedAt()) {
443 if (!First)
444 CallSiteLoc << " @ ";
445 // Note that negative line offset is actually possible, but we use
446 // unsigned int to match line offset representation in remarks so
447 // it's directly consumable by relay advisor.
448 uint32_t Offset =
449 DIL->getLine() - DIL->getScope()->getSubprogram()->getLine();
450 uint32_t Discriminator = DIL->getBaseDiscriminator();
451 StringRef Name = DIL->getScope()->getSubprogram()->getLinkageName();
452 if (Name.empty())
453 Name = DIL->getScope()->getSubprogram()->getName();
454 CallSiteLoc << Name.str() << ":" << llvm::utostr(Offset);
455 if (Format.outputColumn())
456 CallSiteLoc << ":" << llvm::utostr(DIL->getColumn());
457 if (Format.outputDiscriminator() && Discriminator)
458 CallSiteLoc << "." << llvm::utostr(Discriminator);
459 First = false;
460 }
461
462 return CallSiteLoc.str();
463 }
464
addLocationToRemarks(OptimizationRemark & Remark,DebugLoc DLoc)465 void llvm::addLocationToRemarks(OptimizationRemark &Remark, DebugLoc DLoc) {
466 if (!DLoc) {
467 return;
468 }
469
470 bool First = true;
471 Remark << " at callsite ";
472 for (DILocation *DIL = DLoc.get(); DIL; DIL = DIL->getInlinedAt()) {
473 if (!First)
474 Remark << " @ ";
475 unsigned int Offset = DIL->getLine();
476 Offset -= DIL->getScope()->getSubprogram()->getLine();
477 unsigned int Discriminator = DIL->getBaseDiscriminator();
478 StringRef Name = DIL->getScope()->getSubprogram()->getLinkageName();
479 if (Name.empty())
480 Name = DIL->getScope()->getSubprogram()->getName();
481 Remark << Name << ":" << ore::NV("Line", Offset) << ":"
482 << ore::NV("Column", DIL->getColumn());
483 if (Discriminator)
484 Remark << "." << ore::NV("Disc", Discriminator);
485 First = false;
486 }
487
488 Remark << ";";
489 }
490
emitInlinedInto(OptimizationRemarkEmitter & ORE,DebugLoc DLoc,const BasicBlock * Block,const Function & Callee,const Function & Caller,bool AlwaysInline,function_ref<void (OptimizationRemark &)> ExtraContext,const char * PassName)491 void llvm::emitInlinedInto(
492 OptimizationRemarkEmitter &ORE, DebugLoc DLoc, const BasicBlock *Block,
493 const Function &Callee, const Function &Caller, bool AlwaysInline,
494 function_ref<void(OptimizationRemark &)> ExtraContext,
495 const char *PassName) {
496 ORE.emit([&]() {
497 StringRef RemarkName = AlwaysInline ? "AlwaysInline" : "Inlined";
498 OptimizationRemark Remark(PassName ? PassName : DEBUG_TYPE, RemarkName,
499 DLoc, Block);
500 Remark << "'" << ore::NV("Callee", &Callee) << "' inlined into '"
501 << ore::NV("Caller", &Caller) << "'";
502 if (ExtraContext)
503 ExtraContext(Remark);
504 addLocationToRemarks(Remark, DLoc);
505 return Remark;
506 });
507 }
508
emitInlinedIntoBasedOnCost(OptimizationRemarkEmitter & ORE,DebugLoc DLoc,const BasicBlock * Block,const Function & Callee,const Function & Caller,const InlineCost & IC,bool ForProfileContext,const char * PassName)509 void llvm::emitInlinedIntoBasedOnCost(
510 OptimizationRemarkEmitter &ORE, DebugLoc DLoc, const BasicBlock *Block,
511 const Function &Callee, const Function &Caller, const InlineCost &IC,
512 bool ForProfileContext, const char *PassName) {
513 llvm::emitInlinedInto(
514 ORE, DLoc, Block, Callee, Caller, IC.isAlways(),
515 [&](OptimizationRemark &Remark) {
516 if (ForProfileContext)
517 Remark << " to match profiling context";
518 Remark << " with " << IC;
519 },
520 PassName);
521 }
522
InlineAdvisor(Module & M,FunctionAnalysisManager & FAM,std::optional<InlineContext> IC)523 InlineAdvisor::InlineAdvisor(Module &M, FunctionAnalysisManager &FAM,
524 std::optional<InlineContext> IC)
525 : M(M), FAM(FAM), IC(IC),
526 AnnotatedInlinePassName((IC && AnnotateInlinePhase)
527 ? llvm::AnnotateInlinePassName(*IC)
528 : DEBUG_TYPE) {
529 if (InlinerFunctionImportStats != InlinerFunctionImportStatsOpts::No) {
530 ImportedFunctionsStats =
531 std::make_unique<ImportedFunctionsInliningStatistics>();
532 ImportedFunctionsStats->setModuleInfo(M);
533 }
534 }
535
~InlineAdvisor()536 InlineAdvisor::~InlineAdvisor() {
537 if (ImportedFunctionsStats) {
538 assert(InlinerFunctionImportStats != InlinerFunctionImportStatsOpts::No);
539 ImportedFunctionsStats->dump(InlinerFunctionImportStats ==
540 InlinerFunctionImportStatsOpts::Verbose);
541 }
542 }
543
getMandatoryAdvice(CallBase & CB,bool Advice)544 std::unique_ptr<InlineAdvice> InlineAdvisor::getMandatoryAdvice(CallBase &CB,
545 bool Advice) {
546 return std::make_unique<MandatoryInlineAdvice>(this, CB, getCallerORE(CB),
547 Advice);
548 }
549
getLTOPhase(ThinOrFullLTOPhase LTOPhase)550 static inline const char *getLTOPhase(ThinOrFullLTOPhase LTOPhase) {
551 switch (LTOPhase) {
552 case (ThinOrFullLTOPhase::None):
553 return "main";
554 case (ThinOrFullLTOPhase::ThinLTOPreLink):
555 case (ThinOrFullLTOPhase::FullLTOPreLink):
556 return "prelink";
557 case (ThinOrFullLTOPhase::ThinLTOPostLink):
558 case (ThinOrFullLTOPhase::FullLTOPostLink):
559 return "postlink";
560 }
561 llvm_unreachable("unreachable");
562 }
563
getInlineAdvisorContext(InlinePass IP)564 static inline const char *getInlineAdvisorContext(InlinePass IP) {
565 switch (IP) {
566 case (InlinePass::AlwaysInliner):
567 return "always-inline";
568 case (InlinePass::CGSCCInliner):
569 return "cgscc-inline";
570 case (InlinePass::EarlyInliner):
571 return "early-inline";
572 case (InlinePass::MLInliner):
573 return "ml-inline";
574 case (InlinePass::ModuleInliner):
575 return "module-inline";
576 case (InlinePass::ReplayCGSCCInliner):
577 return "replay-cgscc-inline";
578 case (InlinePass::ReplaySampleProfileInliner):
579 return "replay-sample-profile-inline";
580 case (InlinePass::SampleProfileInliner):
581 return "sample-profile-inline";
582 }
583
584 llvm_unreachable("unreachable");
585 }
586
AnnotateInlinePassName(InlineContext IC)587 std::string llvm::AnnotateInlinePassName(InlineContext IC) {
588 return std::string(getLTOPhase(IC.LTOPhase)) + "-" +
589 std::string(getInlineAdvisorContext(IC.Pass));
590 }
591
592 InlineAdvisor::MandatoryInliningKind
getMandatoryKind(CallBase & CB,FunctionAnalysisManager & FAM,OptimizationRemarkEmitter & ORE)593 InlineAdvisor::getMandatoryKind(CallBase &CB, FunctionAnalysisManager &FAM,
594 OptimizationRemarkEmitter &ORE) {
595 auto &Callee = *CB.getCalledFunction();
596
597 auto GetTLI = [&](Function &F) -> const TargetLibraryInfo & {
598 return FAM.getResult<TargetLibraryAnalysis>(F);
599 };
600
601 auto &TIR = FAM.getResult<TargetIRAnalysis>(Callee);
602
603 auto TrivialDecision =
604 llvm::getAttributeBasedInliningDecision(CB, &Callee, TIR, GetTLI);
605
606 if (TrivialDecision) {
607 if (TrivialDecision->isSuccess())
608 return MandatoryInliningKind::Always;
609 else
610 return MandatoryInliningKind::Never;
611 }
612 return MandatoryInliningKind::NotMandatory;
613 }
614
getAdvice(CallBase & CB,bool MandatoryOnly)615 std::unique_ptr<InlineAdvice> InlineAdvisor::getAdvice(CallBase &CB,
616 bool MandatoryOnly) {
617 if (!MandatoryOnly)
618 return getAdviceImpl(CB);
619 bool Advice = CB.getCaller() != CB.getCalledFunction() &&
620 MandatoryInliningKind::Always ==
621 getMandatoryKind(CB, FAM, getCallerORE(CB));
622 return getMandatoryAdvice(CB, Advice);
623 }
624
getCallerORE(CallBase & CB)625 OptimizationRemarkEmitter &InlineAdvisor::getCallerORE(CallBase &CB) {
626 return FAM.getResult<OptimizationRemarkEmitterAnalysis>(*CB.getCaller());
627 }
628
629 PreservedAnalyses
run(Module & M,ModuleAnalysisManager & MAM)630 InlineAdvisorAnalysisPrinterPass::run(Module &M, ModuleAnalysisManager &MAM) {
631 const auto *IA = MAM.getCachedResult<InlineAdvisorAnalysis>(M);
632 if (!IA)
633 OS << "No Inline Advisor\n";
634 else
635 IA->getAdvisor()->print(OS);
636 return PreservedAnalyses::all();
637 }
638
run(LazyCallGraph::SCC & InitialC,CGSCCAnalysisManager & AM,LazyCallGraph & CG,CGSCCUpdateResult & UR)639 PreservedAnalyses InlineAdvisorAnalysisPrinterPass::run(
640 LazyCallGraph::SCC &InitialC, CGSCCAnalysisManager &AM, LazyCallGraph &CG,
641 CGSCCUpdateResult &UR) {
642 const auto &MAMProxy =
643 AM.getResult<ModuleAnalysisManagerCGSCCProxy>(InitialC, CG);
644
645 if (InitialC.size() == 0) {
646 OS << "SCC is empty!\n";
647 return PreservedAnalyses::all();
648 }
649 Module &M = *InitialC.begin()->getFunction().getParent();
650 const auto *IA = MAMProxy.getCachedResult<InlineAdvisorAnalysis>(M);
651 if (!IA)
652 OS << "No Inline Advisor\n";
653 else
654 IA->getAdvisor()->print(OS);
655 return PreservedAnalyses::all();
656 }
657