File: | lib/Transforms/IPO/SampleProfile.cpp |
Warning: | line 727, column 10 Called C++ object pointer is null |
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1 | //===- SampleProfile.cpp - Incorporate sample profiles into the IR --------===// | |||
2 | // | |||
3 | // The LLVM Compiler Infrastructure | |||
4 | // | |||
5 | // This file is distributed under the University of Illinois Open Source | |||
6 | // License. See LICENSE.TXT for details. | |||
7 | // | |||
8 | //===----------------------------------------------------------------------===// | |||
9 | // | |||
10 | // This file implements the SampleProfileLoader transformation. This pass | |||
11 | // reads a profile file generated by a sampling profiler (e.g. Linux Perf - | |||
12 | // http://perf.wiki.kernel.org/) and generates IR metadata to reflect the | |||
13 | // profile information in the given profile. | |||
14 | // | |||
15 | // This pass generates branch weight annotations on the IR: | |||
16 | // | |||
17 | // - prof: Represents branch weights. This annotation is added to branches | |||
18 | // to indicate the weights of each edge coming out of the branch. | |||
19 | // The weight of each edge is the weight of the target block for | |||
20 | // that edge. The weight of a block B is computed as the maximum | |||
21 | // number of samples found in B. | |||
22 | // | |||
23 | //===----------------------------------------------------------------------===// | |||
24 | ||||
25 | #include "llvm/Transforms/IPO/SampleProfile.h" | |||
26 | #include "llvm/ADT/ArrayRef.h" | |||
27 | #include "llvm/ADT/DenseMap.h" | |||
28 | #include "llvm/ADT/DenseSet.h" | |||
29 | #include "llvm/ADT/None.h" | |||
30 | #include "llvm/ADT/SmallPtrSet.h" | |||
31 | #include "llvm/ADT/SmallSet.h" | |||
32 | #include "llvm/ADT/SmallVector.h" | |||
33 | #include "llvm/ADT/StringMap.h" | |||
34 | #include "llvm/ADT/StringRef.h" | |||
35 | #include "llvm/ADT/Twine.h" | |||
36 | #include "llvm/Analysis/AssumptionCache.h" | |||
37 | #include "llvm/Analysis/InlineCost.h" | |||
38 | #include "llvm/Analysis/LoopInfo.h" | |||
39 | #include "llvm/Analysis/OptimizationRemarkEmitter.h" | |||
40 | #include "llvm/Analysis/PostDominators.h" | |||
41 | #include "llvm/Analysis/ProfileSummaryInfo.h" | |||
42 | #include "llvm/Analysis/TargetTransformInfo.h" | |||
43 | #include "llvm/IR/BasicBlock.h" | |||
44 | #include "llvm/IR/CFG.h" | |||
45 | #include "llvm/IR/CallSite.h" | |||
46 | #include "llvm/IR/DebugInfoMetadata.h" | |||
47 | #include "llvm/IR/DebugLoc.h" | |||
48 | #include "llvm/IR/DiagnosticInfo.h" | |||
49 | #include "llvm/IR/Dominators.h" | |||
50 | #include "llvm/IR/Function.h" | |||
51 | #include "llvm/IR/GlobalValue.h" | |||
52 | #include "llvm/IR/InstrTypes.h" | |||
53 | #include "llvm/IR/Instruction.h" | |||
54 | #include "llvm/IR/Instructions.h" | |||
55 | #include "llvm/IR/IntrinsicInst.h" | |||
56 | #include "llvm/IR/LLVMContext.h" | |||
57 | #include "llvm/IR/MDBuilder.h" | |||
58 | #include "llvm/IR/Module.h" | |||
59 | #include "llvm/IR/PassManager.h" | |||
60 | #include "llvm/IR/ValueSymbolTable.h" | |||
61 | #include "llvm/Pass.h" | |||
62 | #include "llvm/ProfileData/InstrProf.h" | |||
63 | #include "llvm/ProfileData/SampleProf.h" | |||
64 | #include "llvm/ProfileData/SampleProfReader.h" | |||
65 | #include "llvm/Support/Casting.h" | |||
66 | #include "llvm/Support/CommandLine.h" | |||
67 | #include "llvm/Support/Debug.h" | |||
68 | #include "llvm/Support/ErrorHandling.h" | |||
69 | #include "llvm/Support/ErrorOr.h" | |||
70 | #include "llvm/Support/GenericDomTree.h" | |||
71 | #include "llvm/Support/raw_ostream.h" | |||
72 | #include "llvm/Transforms/IPO.h" | |||
73 | #include "llvm/Transforms/Instrumentation.h" | |||
74 | #include "llvm/Transforms/Utils/CallPromotionUtils.h" | |||
75 | #include "llvm/Transforms/Utils/Cloning.h" | |||
76 | #include <algorithm> | |||
77 | #include <cassert> | |||
78 | #include <cstdint> | |||
79 | #include <functional> | |||
80 | #include <limits> | |||
81 | #include <map> | |||
82 | #include <memory> | |||
83 | #include <string> | |||
84 | #include <system_error> | |||
85 | #include <utility> | |||
86 | #include <vector> | |||
87 | ||||
88 | using namespace llvm; | |||
89 | using namespace sampleprof; | |||
90 | using ProfileCount = Function::ProfileCount; | |||
91 | #define DEBUG_TYPE"sample-profile" "sample-profile" | |||
92 | ||||
93 | // Command line option to specify the file to read samples from. This is | |||
94 | // mainly used for debugging. | |||
95 | static cl::opt<std::string> SampleProfileFile( | |||
96 | "sample-profile-file", cl::init(""), cl::value_desc("filename"), | |||
97 | cl::desc("Profile file loaded by -sample-profile"), cl::Hidden); | |||
98 | ||||
99 | // The named file contains a set of transformations that may have been applied | |||
100 | // to the symbol names between the program from which the sample data was | |||
101 | // collected and the current program's symbols. | |||
102 | static cl::opt<std::string> SampleProfileRemappingFile( | |||
103 | "sample-profile-remapping-file", cl::init(""), cl::value_desc("filename"), | |||
104 | cl::desc("Profile remapping file loaded by -sample-profile"), cl::Hidden); | |||
105 | ||||
106 | static cl::opt<unsigned> SampleProfileMaxPropagateIterations( | |||
107 | "sample-profile-max-propagate-iterations", cl::init(100), | |||
108 | cl::desc("Maximum number of iterations to go through when propagating " | |||
109 | "sample block/edge weights through the CFG.")); | |||
110 | ||||
111 | static cl::opt<unsigned> SampleProfileRecordCoverage( | |||
112 | "sample-profile-check-record-coverage", cl::init(0), cl::value_desc("N"), | |||
113 | cl::desc("Emit a warning if less than N% of records in the input profile " | |||
114 | "are matched to the IR.")); | |||
115 | ||||
116 | static cl::opt<unsigned> SampleProfileSampleCoverage( | |||
117 | "sample-profile-check-sample-coverage", cl::init(0), cl::value_desc("N"), | |||
118 | cl::desc("Emit a warning if less than N% of samples in the input profile " | |||
119 | "are matched to the IR.")); | |||
120 | ||||
121 | static cl::opt<bool> NoWarnSampleUnused( | |||
122 | "no-warn-sample-unused", cl::init(false), cl::Hidden, | |||
123 | cl::desc("Use this option to turn off/on warnings about function with " | |||
124 | "samples but without debug information to use those samples. ")); | |||
125 | ||||
126 | static cl::opt<bool> ProfileSampleAccurate( | |||
127 | "profile-sample-accurate", cl::Hidden, cl::init(false), | |||
128 | cl::desc("If the sample profile is accurate, we will mark all un-sampled " | |||
129 | "callsite and function as having 0 samples. Otherwise, treat " | |||
130 | "un-sampled callsites and functions conservatively as unknown. ")); | |||
131 | ||||
132 | namespace { | |||
133 | ||||
134 | using BlockWeightMap = DenseMap<const BasicBlock *, uint64_t>; | |||
135 | using EquivalenceClassMap = DenseMap<const BasicBlock *, const BasicBlock *>; | |||
136 | using Edge = std::pair<const BasicBlock *, const BasicBlock *>; | |||
137 | using EdgeWeightMap = DenseMap<Edge, uint64_t>; | |||
138 | using BlockEdgeMap = | |||
139 | DenseMap<const BasicBlock *, SmallVector<const BasicBlock *, 8>>; | |||
140 | ||||
141 | class SampleCoverageTracker { | |||
142 | public: | |||
143 | SampleCoverageTracker() = default; | |||
144 | ||||
145 | bool markSamplesUsed(const FunctionSamples *FS, uint32_t LineOffset, | |||
146 | uint32_t Discriminator, uint64_t Samples); | |||
147 | unsigned computeCoverage(unsigned Used, unsigned Total) const; | |||
148 | unsigned countUsedRecords(const FunctionSamples *FS, | |||
149 | ProfileSummaryInfo *PSI) const; | |||
150 | unsigned countBodyRecords(const FunctionSamples *FS, | |||
151 | ProfileSummaryInfo *PSI) const; | |||
152 | uint64_t getTotalUsedSamples() const { return TotalUsedSamples; } | |||
153 | uint64_t countBodySamples(const FunctionSamples *FS, | |||
154 | ProfileSummaryInfo *PSI) const; | |||
155 | ||||
156 | void clear() { | |||
157 | SampleCoverage.clear(); | |||
158 | TotalUsedSamples = 0; | |||
159 | } | |||
160 | ||||
161 | private: | |||
162 | using BodySampleCoverageMap = std::map<LineLocation, unsigned>; | |||
163 | using FunctionSamplesCoverageMap = | |||
164 | DenseMap<const FunctionSamples *, BodySampleCoverageMap>; | |||
165 | ||||
166 | /// Coverage map for sampling records. | |||
167 | /// | |||
168 | /// This map keeps a record of sampling records that have been matched to | |||
169 | /// an IR instruction. This is used to detect some form of staleness in | |||
170 | /// profiles (see flag -sample-profile-check-coverage). | |||
171 | /// | |||
172 | /// Each entry in the map corresponds to a FunctionSamples instance. This is | |||
173 | /// another map that counts how many times the sample record at the | |||
174 | /// given location has been used. | |||
175 | FunctionSamplesCoverageMap SampleCoverage; | |||
176 | ||||
177 | /// Number of samples used from the profile. | |||
178 | /// | |||
179 | /// When a sampling record is used for the first time, the samples from | |||
180 | /// that record are added to this accumulator. Coverage is later computed | |||
181 | /// based on the total number of samples available in this function and | |||
182 | /// its callsites. | |||
183 | /// | |||
184 | /// Note that this accumulator tracks samples used from a single function | |||
185 | /// and all the inlined callsites. Strictly, we should have a map of counters | |||
186 | /// keyed by FunctionSamples pointers, but these stats are cleared after | |||
187 | /// every function, so we just need to keep a single counter. | |||
188 | uint64_t TotalUsedSamples = 0; | |||
189 | }; | |||
190 | ||||
191 | /// Sample profile pass. | |||
192 | /// | |||
193 | /// This pass reads profile data from the file specified by | |||
194 | /// -sample-profile-file and annotates every affected function with the | |||
195 | /// profile information found in that file. | |||
196 | class SampleProfileLoader { | |||
197 | public: | |||
198 | SampleProfileLoader( | |||
199 | StringRef Name, StringRef RemapName, bool IsThinLTOPreLink, | |||
200 | std::function<AssumptionCache &(Function &)> GetAssumptionCache, | |||
201 | std::function<TargetTransformInfo &(Function &)> GetTargetTransformInfo) | |||
202 | : GetAC(std::move(GetAssumptionCache)), | |||
203 | GetTTI(std::move(GetTargetTransformInfo)), Filename(Name), | |||
204 | RemappingFilename(RemapName), IsThinLTOPreLink(IsThinLTOPreLink) {} | |||
205 | ||||
206 | bool doInitialization(Module &M); | |||
207 | bool runOnModule(Module &M, ModuleAnalysisManager *AM, | |||
208 | ProfileSummaryInfo *_PSI); | |||
209 | ||||
210 | void dump() { Reader->dump(); } | |||
211 | ||||
212 | protected: | |||
213 | bool runOnFunction(Function &F, ModuleAnalysisManager *AM); | |||
214 | unsigned getFunctionLoc(Function &F); | |||
215 | bool emitAnnotations(Function &F); | |||
216 | ErrorOr<uint64_t> getInstWeight(const Instruction &I); | |||
217 | ErrorOr<uint64_t> getBlockWeight(const BasicBlock *BB); | |||
218 | const FunctionSamples *findCalleeFunctionSamples(const Instruction &I) const; | |||
219 | std::vector<const FunctionSamples *> | |||
220 | findIndirectCallFunctionSamples(const Instruction &I, uint64_t &Sum) const; | |||
221 | const FunctionSamples *findFunctionSamples(const Instruction &I) const; | |||
222 | bool inlineCallInstruction(Instruction *I); | |||
223 | bool inlineHotFunctions(Function &F, | |||
224 | DenseSet<GlobalValue::GUID> &InlinedGUIDs); | |||
225 | void printEdgeWeight(raw_ostream &OS, Edge E); | |||
226 | void printBlockWeight(raw_ostream &OS, const BasicBlock *BB) const; | |||
227 | void printBlockEquivalence(raw_ostream &OS, const BasicBlock *BB); | |||
228 | bool computeBlockWeights(Function &F); | |||
229 | void findEquivalenceClasses(Function &F); | |||
230 | template <bool IsPostDom> | |||
231 | void findEquivalencesFor(BasicBlock *BB1, ArrayRef<BasicBlock *> Descendants, | |||
232 | DominatorTreeBase<BasicBlock, IsPostDom> *DomTree); | |||
233 | ||||
234 | void propagateWeights(Function &F); | |||
235 | uint64_t visitEdge(Edge E, unsigned *NumUnknownEdges, Edge *UnknownEdge); | |||
236 | void buildEdges(Function &F); | |||
237 | bool propagateThroughEdges(Function &F, bool UpdateBlockCount); | |||
238 | void computeDominanceAndLoopInfo(Function &F); | |||
239 | void clearFunctionData(); | |||
240 | ||||
241 | /// Map basic blocks to their computed weights. | |||
242 | /// | |||
243 | /// The weight of a basic block is defined to be the maximum | |||
244 | /// of all the instruction weights in that block. | |||
245 | BlockWeightMap BlockWeights; | |||
246 | ||||
247 | /// Map edges to their computed weights. | |||
248 | /// | |||
249 | /// Edge weights are computed by propagating basic block weights in | |||
250 | /// SampleProfile::propagateWeights. | |||
251 | EdgeWeightMap EdgeWeights; | |||
252 | ||||
253 | /// Set of visited blocks during propagation. | |||
254 | SmallPtrSet<const BasicBlock *, 32> VisitedBlocks; | |||
255 | ||||
256 | /// Set of visited edges during propagation. | |||
257 | SmallSet<Edge, 32> VisitedEdges; | |||
258 | ||||
259 | /// Equivalence classes for block weights. | |||
260 | /// | |||
261 | /// Two blocks BB1 and BB2 are in the same equivalence class if they | |||
262 | /// dominate and post-dominate each other, and they are in the same loop | |||
263 | /// nest. When this happens, the two blocks are guaranteed to execute | |||
264 | /// the same number of times. | |||
265 | EquivalenceClassMap EquivalenceClass; | |||
266 | ||||
267 | /// Map from function name to Function *. Used to find the function from | |||
268 | /// the function name. If the function name contains suffix, additional | |||
269 | /// entry is added to map from the stripped name to the function if there | |||
270 | /// is one-to-one mapping. | |||
271 | StringMap<Function *> SymbolMap; | |||
272 | ||||
273 | /// Dominance, post-dominance and loop information. | |||
274 | std::unique_ptr<DominatorTree> DT; | |||
275 | std::unique_ptr<PostDominatorTree> PDT; | |||
276 | std::unique_ptr<LoopInfo> LI; | |||
277 | ||||
278 | std::function<AssumptionCache &(Function &)> GetAC; | |||
279 | std::function<TargetTransformInfo &(Function &)> GetTTI; | |||
280 | ||||
281 | /// Predecessors for each basic block in the CFG. | |||
282 | BlockEdgeMap Predecessors; | |||
283 | ||||
284 | /// Successors for each basic block in the CFG. | |||
285 | BlockEdgeMap Successors; | |||
286 | ||||
287 | SampleCoverageTracker CoverageTracker; | |||
288 | ||||
289 | /// Profile reader object. | |||
290 | std::unique_ptr<SampleProfileReader> Reader; | |||
291 | ||||
292 | /// Samples collected for the body of this function. | |||
293 | FunctionSamples *Samples = nullptr; | |||
294 | ||||
295 | /// Name of the profile file to load. | |||
296 | std::string Filename; | |||
297 | ||||
298 | /// Name of the profile remapping file to load. | |||
299 | std::string RemappingFilename; | |||
300 | ||||
301 | /// Flag indicating whether the profile input loaded successfully. | |||
302 | bool ProfileIsValid = false; | |||
303 | ||||
304 | /// Flag indicating if the pass is invoked in ThinLTO compile phase. | |||
305 | /// | |||
306 | /// In this phase, in annotation, we should not promote indirect calls. | |||
307 | /// Instead, we will mark GUIDs that needs to be annotated to the function. | |||
308 | bool IsThinLTOPreLink; | |||
309 | ||||
310 | /// Profile Summary Info computed from sample profile. | |||
311 | ProfileSummaryInfo *PSI = nullptr; | |||
312 | ||||
313 | /// Total number of samples collected in this profile. | |||
314 | /// | |||
315 | /// This is the sum of all the samples collected in all the functions executed | |||
316 | /// at runtime. | |||
317 | uint64_t TotalCollectedSamples = 0; | |||
318 | ||||
319 | /// Optimization Remark Emitter used to emit diagnostic remarks. | |||
320 | OptimizationRemarkEmitter *ORE = nullptr; | |||
321 | }; | |||
322 | ||||
323 | class SampleProfileLoaderLegacyPass : public ModulePass { | |||
324 | public: | |||
325 | // Class identification, replacement for typeinfo | |||
326 | static char ID; | |||
327 | ||||
328 | SampleProfileLoaderLegacyPass(StringRef Name = SampleProfileFile, | |||
329 | bool IsThinLTOPreLink = false) | |||
330 | : ModulePass(ID), | |||
331 | SampleLoader(Name, SampleProfileRemappingFile, IsThinLTOPreLink, | |||
332 | [&](Function &F) -> AssumptionCache & { | |||
333 | return ACT->getAssumptionCache(F); | |||
334 | }, | |||
335 | [&](Function &F) -> TargetTransformInfo & { | |||
336 | return TTIWP->getTTI(F); | |||
337 | }) { | |||
338 | initializeSampleProfileLoaderLegacyPassPass( | |||
339 | *PassRegistry::getPassRegistry()); | |||
340 | } | |||
341 | ||||
342 | void dump() { SampleLoader.dump(); } | |||
343 | ||||
344 | bool doInitialization(Module &M) override { | |||
345 | return SampleLoader.doInitialization(M); | |||
346 | } | |||
347 | ||||
348 | StringRef getPassName() const override { return "Sample profile pass"; } | |||
349 | bool runOnModule(Module &M) override; | |||
350 | ||||
351 | void getAnalysisUsage(AnalysisUsage &AU) const override { | |||
352 | AU.addRequired<AssumptionCacheTracker>(); | |||
353 | AU.addRequired<TargetTransformInfoWrapperPass>(); | |||
354 | AU.addRequired<ProfileSummaryInfoWrapperPass>(); | |||
355 | } | |||
356 | ||||
357 | private: | |||
358 | SampleProfileLoader SampleLoader; | |||
359 | AssumptionCacheTracker *ACT = nullptr; | |||
360 | TargetTransformInfoWrapperPass *TTIWP = nullptr; | |||
361 | }; | |||
362 | ||||
363 | } // end anonymous namespace | |||
364 | ||||
365 | /// Return true if the given callsite is hot wrt to hot cutoff threshold. | |||
366 | /// | |||
367 | /// Functions that were inlined in the original binary will be represented | |||
368 | /// in the inline stack in the sample profile. If the profile shows that | |||
369 | /// the original inline decision was "good" (i.e., the callsite is executed | |||
370 | /// frequently), then we will recreate the inline decision and apply the | |||
371 | /// profile from the inlined callsite. | |||
372 | /// | |||
373 | /// To decide whether an inlined callsite is hot, we compare the callsite | |||
374 | /// sample count with the hot cutoff computed by ProfileSummaryInfo, it is | |||
375 | /// regarded as hot if the count is above the cutoff value. | |||
376 | static bool callsiteIsHot(const FunctionSamples *CallsiteFS, | |||
377 | ProfileSummaryInfo *PSI) { | |||
378 | if (!CallsiteFS) | |||
379 | return false; // The callsite was not inlined in the original binary. | |||
380 | ||||
381 | assert(PSI && "PSI is expected to be non null")((PSI && "PSI is expected to be non null") ? static_cast <void> (0) : __assert_fail ("PSI && \"PSI is expected to be non null\"" , "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 381, __PRETTY_FUNCTION__)); | |||
382 | uint64_t CallsiteTotalSamples = CallsiteFS->getTotalSamples(); | |||
383 | return PSI->isHotCount(CallsiteTotalSamples); | |||
384 | } | |||
385 | ||||
386 | /// Mark as used the sample record for the given function samples at | |||
387 | /// (LineOffset, Discriminator). | |||
388 | /// | |||
389 | /// \returns true if this is the first time we mark the given record. | |||
390 | bool SampleCoverageTracker::markSamplesUsed(const FunctionSamples *FS, | |||
391 | uint32_t LineOffset, | |||
392 | uint32_t Discriminator, | |||
393 | uint64_t Samples) { | |||
394 | LineLocation Loc(LineOffset, Discriminator); | |||
395 | unsigned &Count = SampleCoverage[FS][Loc]; | |||
396 | bool FirstTime = (++Count == 1); | |||
397 | if (FirstTime) | |||
398 | TotalUsedSamples += Samples; | |||
399 | return FirstTime; | |||
400 | } | |||
401 | ||||
402 | /// Return the number of sample records that were applied from this profile. | |||
403 | /// | |||
404 | /// This count does not include records from cold inlined callsites. | |||
405 | unsigned | |||
406 | SampleCoverageTracker::countUsedRecords(const FunctionSamples *FS, | |||
407 | ProfileSummaryInfo *PSI) const { | |||
408 | auto I = SampleCoverage.find(FS); | |||
409 | ||||
410 | // The size of the coverage map for FS represents the number of records | |||
411 | // that were marked used at least once. | |||
412 | unsigned Count = (I != SampleCoverage.end()) ? I->second.size() : 0; | |||
413 | ||||
414 | // If there are inlined callsites in this function, count the samples found | |||
415 | // in the respective bodies. However, do not bother counting callees with 0 | |||
416 | // total samples, these are callees that were never invoked at runtime. | |||
417 | for (const auto &I : FS->getCallsiteSamples()) | |||
418 | for (const auto &J : I.second) { | |||
419 | const FunctionSamples *CalleeSamples = &J.second; | |||
420 | if (callsiteIsHot(CalleeSamples, PSI)) | |||
421 | Count += countUsedRecords(CalleeSamples, PSI); | |||
422 | } | |||
423 | ||||
424 | return Count; | |||
425 | } | |||
426 | ||||
427 | /// Return the number of sample records in the body of this profile. | |||
428 | /// | |||
429 | /// This count does not include records from cold inlined callsites. | |||
430 | unsigned | |||
431 | SampleCoverageTracker::countBodyRecords(const FunctionSamples *FS, | |||
432 | ProfileSummaryInfo *PSI) const { | |||
433 | unsigned Count = FS->getBodySamples().size(); | |||
434 | ||||
435 | // Only count records in hot callsites. | |||
436 | for (const auto &I : FS->getCallsiteSamples()) | |||
437 | for (const auto &J : I.second) { | |||
438 | const FunctionSamples *CalleeSamples = &J.second; | |||
439 | if (callsiteIsHot(CalleeSamples, PSI)) | |||
440 | Count += countBodyRecords(CalleeSamples, PSI); | |||
441 | } | |||
442 | ||||
443 | return Count; | |||
444 | } | |||
445 | ||||
446 | /// Return the number of samples collected in the body of this profile. | |||
447 | /// | |||
448 | /// This count does not include samples from cold inlined callsites. | |||
449 | uint64_t | |||
450 | SampleCoverageTracker::countBodySamples(const FunctionSamples *FS, | |||
451 | ProfileSummaryInfo *PSI) const { | |||
452 | uint64_t Total = 0; | |||
453 | for (const auto &I : FS->getBodySamples()) | |||
454 | Total += I.second.getSamples(); | |||
455 | ||||
456 | // Only count samples in hot callsites. | |||
457 | for (const auto &I : FS->getCallsiteSamples()) | |||
458 | for (const auto &J : I.second) { | |||
459 | const FunctionSamples *CalleeSamples = &J.second; | |||
460 | if (callsiteIsHot(CalleeSamples, PSI)) | |||
461 | Total += countBodySamples(CalleeSamples, PSI); | |||
462 | } | |||
463 | ||||
464 | return Total; | |||
465 | } | |||
466 | ||||
467 | /// Return the fraction of sample records used in this profile. | |||
468 | /// | |||
469 | /// The returned value is an unsigned integer in the range 0-100 indicating | |||
470 | /// the percentage of sample records that were used while applying this | |||
471 | /// profile to the associated function. | |||
472 | unsigned SampleCoverageTracker::computeCoverage(unsigned Used, | |||
473 | unsigned Total) const { | |||
474 | assert(Used <= Total &&((Used <= Total && "number of used records cannot exceed the total number of records" ) ? static_cast<void> (0) : __assert_fail ("Used <= Total && \"number of used records cannot exceed the total number of records\"" , "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 475, __PRETTY_FUNCTION__)) | |||
475 | "number of used records cannot exceed the total number of records")((Used <= Total && "number of used records cannot exceed the total number of records" ) ? static_cast<void> (0) : __assert_fail ("Used <= Total && \"number of used records cannot exceed the total number of records\"" , "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 475, __PRETTY_FUNCTION__)); | |||
476 | return Total > 0 ? Used * 100 / Total : 100; | |||
477 | } | |||
478 | ||||
479 | /// Clear all the per-function data used to load samples and propagate weights. | |||
480 | void SampleProfileLoader::clearFunctionData() { | |||
481 | BlockWeights.clear(); | |||
482 | EdgeWeights.clear(); | |||
483 | VisitedBlocks.clear(); | |||
484 | VisitedEdges.clear(); | |||
485 | EquivalenceClass.clear(); | |||
486 | DT = nullptr; | |||
487 | PDT = nullptr; | |||
488 | LI = nullptr; | |||
489 | Predecessors.clear(); | |||
490 | Successors.clear(); | |||
491 | CoverageTracker.clear(); | |||
492 | } | |||
493 | ||||
494 | #ifndef NDEBUG | |||
495 | /// Print the weight of edge \p E on stream \p OS. | |||
496 | /// | |||
497 | /// \param OS Stream to emit the output to. | |||
498 | /// \param E Edge to print. | |||
499 | void SampleProfileLoader::printEdgeWeight(raw_ostream &OS, Edge E) { | |||
500 | OS << "weight[" << E.first->getName() << "->" << E.second->getName() | |||
501 | << "]: " << EdgeWeights[E] << "\n"; | |||
502 | } | |||
503 | ||||
504 | /// Print the equivalence class of block \p BB on stream \p OS. | |||
505 | /// | |||
506 | /// \param OS Stream to emit the output to. | |||
507 | /// \param BB Block to print. | |||
508 | void SampleProfileLoader::printBlockEquivalence(raw_ostream &OS, | |||
509 | const BasicBlock *BB) { | |||
510 | const BasicBlock *Equiv = EquivalenceClass[BB]; | |||
511 | OS << "equivalence[" << BB->getName() | |||
512 | << "]: " << ((Equiv) ? EquivalenceClass[BB]->getName() : "NONE") << "\n"; | |||
513 | } | |||
514 | ||||
515 | /// Print the weight of block \p BB on stream \p OS. | |||
516 | /// | |||
517 | /// \param OS Stream to emit the output to. | |||
518 | /// \param BB Block to print. | |||
519 | void SampleProfileLoader::printBlockWeight(raw_ostream &OS, | |||
520 | const BasicBlock *BB) const { | |||
521 | const auto &I = BlockWeights.find(BB); | |||
522 | uint64_t W = (I == BlockWeights.end() ? 0 : I->second); | |||
523 | OS << "weight[" << BB->getName() << "]: " << W << "\n"; | |||
524 | } | |||
525 | #endif | |||
526 | ||||
527 | /// Get the weight for an instruction. | |||
528 | /// | |||
529 | /// The "weight" of an instruction \p Inst is the number of samples | |||
530 | /// collected on that instruction at runtime. To retrieve it, we | |||
531 | /// need to compute the line number of \p Inst relative to the start of its | |||
532 | /// function. We use HeaderLineno to compute the offset. We then | |||
533 | /// look up the samples collected for \p Inst using BodySamples. | |||
534 | /// | |||
535 | /// \param Inst Instruction to query. | |||
536 | /// | |||
537 | /// \returns the weight of \p Inst. | |||
538 | ErrorOr<uint64_t> SampleProfileLoader::getInstWeight(const Instruction &Inst) { | |||
539 | const DebugLoc &DLoc = Inst.getDebugLoc(); | |||
540 | if (!DLoc) | |||
541 | return std::error_code(); | |||
542 | ||||
543 | const FunctionSamples *FS = findFunctionSamples(Inst); | |||
544 | if (!FS) | |||
545 | return std::error_code(); | |||
546 | ||||
547 | // Ignore all intrinsics and branch instructions. | |||
548 | // Branch instruction usually contains debug info from sources outside of | |||
549 | // the residing basic block, thus we ignore them during annotation. | |||
550 | if (isa<BranchInst>(Inst) || isa<IntrinsicInst>(Inst)) | |||
551 | return std::error_code(); | |||
552 | ||||
553 | // If a direct call/invoke instruction is inlined in profile | |||
554 | // (findCalleeFunctionSamples returns non-empty result), but not inlined here, | |||
555 | // it means that the inlined callsite has no sample, thus the call | |||
556 | // instruction should have 0 count. | |||
557 | if ((isa<CallInst>(Inst) || isa<InvokeInst>(Inst)) && | |||
558 | !ImmutableCallSite(&Inst).isIndirectCall() && | |||
559 | findCalleeFunctionSamples(Inst)) | |||
560 | return 0; | |||
561 | ||||
562 | const DILocation *DIL = DLoc; | |||
563 | uint32_t LineOffset = FunctionSamples::getOffset(DIL); | |||
564 | uint32_t Discriminator = DIL->getBaseDiscriminator(); | |||
565 | ErrorOr<uint64_t> R = FS->findSamplesAt(LineOffset, Discriminator); | |||
566 | if (R) { | |||
567 | bool FirstMark = | |||
568 | CoverageTracker.markSamplesUsed(FS, LineOffset, Discriminator, R.get()); | |||
569 | if (FirstMark) { | |||
570 | ORE->emit([&]() { | |||
571 | OptimizationRemarkAnalysis Remark(DEBUG_TYPE"sample-profile", "AppliedSamples", &Inst); | |||
572 | Remark << "Applied " << ore::NV("NumSamples", *R); | |||
573 | Remark << " samples from profile (offset: "; | |||
574 | Remark << ore::NV("LineOffset", LineOffset); | |||
575 | if (Discriminator) { | |||
576 | Remark << "."; | |||
577 | Remark << ore::NV("Discriminator", Discriminator); | |||
578 | } | |||
579 | Remark << ")"; | |||
580 | return Remark; | |||
581 | }); | |||
582 | } | |||
583 | LLVM_DEBUG(dbgs() << " " << DLoc.getLine() << "."do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << " " << DLoc.getLine () << "." << DIL->getBaseDiscriminator() << ":" << Inst << " (line offset: " << LineOffset << "." << DIL->getBaseDiscriminator() << " - weight: " << R.get() << ")\n"; } } while (false ) | |||
584 | << DIL->getBaseDiscriminator() << ":" << Instdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << " " << DLoc.getLine () << "." << DIL->getBaseDiscriminator() << ":" << Inst << " (line offset: " << LineOffset << "." << DIL->getBaseDiscriminator() << " - weight: " << R.get() << ")\n"; } } while (false ) | |||
585 | << " (line offset: " << LineOffset << "."do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << " " << DLoc.getLine () << "." << DIL->getBaseDiscriminator() << ":" << Inst << " (line offset: " << LineOffset << "." << DIL->getBaseDiscriminator() << " - weight: " << R.get() << ")\n"; } } while (false ) | |||
586 | << DIL->getBaseDiscriminator() << " - weight: " << R.get()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << " " << DLoc.getLine () << "." << DIL->getBaseDiscriminator() << ":" << Inst << " (line offset: " << LineOffset << "." << DIL->getBaseDiscriminator() << " - weight: " << R.get() << ")\n"; } } while (false ) | |||
587 | << ")\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << " " << DLoc.getLine () << "." << DIL->getBaseDiscriminator() << ":" << Inst << " (line offset: " << LineOffset << "." << DIL->getBaseDiscriminator() << " - weight: " << R.get() << ")\n"; } } while (false ); | |||
588 | } | |||
589 | return R; | |||
590 | } | |||
591 | ||||
592 | /// Compute the weight of a basic block. | |||
593 | /// | |||
594 | /// The weight of basic block \p BB is the maximum weight of all the | |||
595 | /// instructions in BB. | |||
596 | /// | |||
597 | /// \param BB The basic block to query. | |||
598 | /// | |||
599 | /// \returns the weight for \p BB. | |||
600 | ErrorOr<uint64_t> SampleProfileLoader::getBlockWeight(const BasicBlock *BB) { | |||
601 | uint64_t Max = 0; | |||
602 | bool HasWeight = false; | |||
603 | for (auto &I : BB->getInstList()) { | |||
604 | const ErrorOr<uint64_t> &R = getInstWeight(I); | |||
| ||||
605 | if (R) { | |||
606 | Max = std::max(Max, R.get()); | |||
607 | HasWeight = true; | |||
608 | } | |||
609 | } | |||
610 | return HasWeight ? ErrorOr<uint64_t>(Max) : std::error_code(); | |||
611 | } | |||
612 | ||||
613 | /// Compute and store the weights of every basic block. | |||
614 | /// | |||
615 | /// This populates the BlockWeights map by computing | |||
616 | /// the weights of every basic block in the CFG. | |||
617 | /// | |||
618 | /// \param F The function to query. | |||
619 | bool SampleProfileLoader::computeBlockWeights(Function &F) { | |||
620 | bool Changed = false; | |||
621 | LLVM_DEBUG(dbgs() << "Block weights\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Block weights\n"; } } while (false); | |||
622 | for (const auto &BB : F) { | |||
623 | ErrorOr<uint64_t> Weight = getBlockWeight(&BB); | |||
624 | if (Weight) { | |||
625 | BlockWeights[&BB] = Weight.get(); | |||
626 | VisitedBlocks.insert(&BB); | |||
627 | Changed = true; | |||
628 | } | |||
629 | LLVM_DEBUG(printBlockWeight(dbgs(), &BB))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { printBlockWeight(dbgs(), &BB); } } while (false); | |||
630 | } | |||
631 | ||||
632 | return Changed; | |||
633 | } | |||
634 | ||||
635 | /// Get the FunctionSamples for a call instruction. | |||
636 | /// | |||
637 | /// The FunctionSamples of a call/invoke instruction \p Inst is the inlined | |||
638 | /// instance in which that call instruction is calling to. It contains | |||
639 | /// all samples that resides in the inlined instance. We first find the | |||
640 | /// inlined instance in which the call instruction is from, then we | |||
641 | /// traverse its children to find the callsite with the matching | |||
642 | /// location. | |||
643 | /// | |||
644 | /// \param Inst Call/Invoke instruction to query. | |||
645 | /// | |||
646 | /// \returns The FunctionSamples pointer to the inlined instance. | |||
647 | const FunctionSamples * | |||
648 | SampleProfileLoader::findCalleeFunctionSamples(const Instruction &Inst) const { | |||
649 | const DILocation *DIL = Inst.getDebugLoc(); | |||
650 | if (!DIL) { | |||
651 | return nullptr; | |||
652 | } | |||
653 | ||||
654 | StringRef CalleeName; | |||
655 | if (const CallInst *CI = dyn_cast<CallInst>(&Inst)) | |||
656 | if (Function *Callee = CI->getCalledFunction()) | |||
657 | CalleeName = Callee->getName(); | |||
658 | ||||
659 | const FunctionSamples *FS = findFunctionSamples(Inst); | |||
660 | if (FS == nullptr) | |||
661 | return nullptr; | |||
662 | ||||
663 | return FS->findFunctionSamplesAt(LineLocation(FunctionSamples::getOffset(DIL), | |||
664 | DIL->getBaseDiscriminator()), | |||
665 | CalleeName); | |||
666 | } | |||
667 | ||||
668 | /// Returns a vector of FunctionSamples that are the indirect call targets | |||
669 | /// of \p Inst. The vector is sorted by the total number of samples. Stores | |||
670 | /// the total call count of the indirect call in \p Sum. | |||
671 | std::vector<const FunctionSamples *> | |||
672 | SampleProfileLoader::findIndirectCallFunctionSamples( | |||
673 | const Instruction &Inst, uint64_t &Sum) const { | |||
674 | const DILocation *DIL = Inst.getDebugLoc(); | |||
675 | std::vector<const FunctionSamples *> R; | |||
676 | ||||
677 | if (!DIL) { | |||
678 | return R; | |||
679 | } | |||
680 | ||||
681 | const FunctionSamples *FS = findFunctionSamples(Inst); | |||
682 | if (FS == nullptr) | |||
683 | return R; | |||
684 | ||||
685 | uint32_t LineOffset = FunctionSamples::getOffset(DIL); | |||
686 | uint32_t Discriminator = DIL->getBaseDiscriminator(); | |||
687 | ||||
688 | auto T = FS->findCallTargetMapAt(LineOffset, Discriminator); | |||
689 | Sum = 0; | |||
690 | if (T) | |||
691 | for (const auto &T_C : T.get()) | |||
692 | Sum += T_C.second; | |||
693 | if (const FunctionSamplesMap *M = FS->findFunctionSamplesMapAt(LineLocation( | |||
694 | FunctionSamples::getOffset(DIL), DIL->getBaseDiscriminator()))) { | |||
695 | if (M->empty()) | |||
696 | return R; | |||
697 | for (const auto &NameFS : *M) { | |||
698 | Sum += NameFS.second.getEntrySamples(); | |||
699 | R.push_back(&NameFS.second); | |||
700 | } | |||
701 | llvm::sort(R, [](const FunctionSamples *L, const FunctionSamples *R) { | |||
702 | if (L->getEntrySamples() != R->getEntrySamples()) | |||
703 | return L->getEntrySamples() > R->getEntrySamples(); | |||
704 | return FunctionSamples::getGUID(L->getName()) < | |||
705 | FunctionSamples::getGUID(R->getName()); | |||
706 | }); | |||
707 | } | |||
708 | return R; | |||
709 | } | |||
710 | ||||
711 | /// Get the FunctionSamples for an instruction. | |||
712 | /// | |||
713 | /// The FunctionSamples of an instruction \p Inst is the inlined instance | |||
714 | /// in which that instruction is coming from. We traverse the inline stack | |||
715 | /// of that instruction, and match it with the tree nodes in the profile. | |||
716 | /// | |||
717 | /// \param Inst Instruction to query. | |||
718 | /// | |||
719 | /// \returns the FunctionSamples pointer to the inlined instance. | |||
720 | const FunctionSamples * | |||
721 | SampleProfileLoader::findFunctionSamples(const Instruction &Inst) const { | |||
722 | SmallVector<std::pair<LineLocation, StringRef>, 10> S; | |||
723 | const DILocation *DIL = Inst.getDebugLoc(); | |||
724 | if (!DIL) | |||
725 | return Samples; | |||
726 | ||||
727 | return Samples->findFunctionSamples(DIL); | |||
| ||||
728 | } | |||
729 | ||||
730 | bool SampleProfileLoader::inlineCallInstruction(Instruction *I) { | |||
731 | assert(isa<CallInst>(I) || isa<InvokeInst>(I))((isa<CallInst>(I) || isa<InvokeInst>(I)) ? static_cast <void> (0) : __assert_fail ("isa<CallInst>(I) || isa<InvokeInst>(I)" , "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 731, __PRETTY_FUNCTION__)); | |||
732 | CallSite CS(I); | |||
733 | Function *CalledFunction = CS.getCalledFunction(); | |||
734 | assert(CalledFunction)((CalledFunction) ? static_cast<void> (0) : __assert_fail ("CalledFunction", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 734, __PRETTY_FUNCTION__)); | |||
735 | DebugLoc DLoc = I->getDebugLoc(); | |||
736 | BasicBlock *BB = I->getParent(); | |||
737 | InlineParams Params = getInlineParams(); | |||
738 | Params.ComputeFullInlineCost = true; | |||
739 | // Checks if there is anything in the reachable portion of the callee at | |||
740 | // this callsite that makes this inlining potentially illegal. Need to | |||
741 | // set ComputeFullInlineCost, otherwise getInlineCost may return early | |||
742 | // when cost exceeds threshold without checking all IRs in the callee. | |||
743 | // The acutal cost does not matter because we only checks isNever() to | |||
744 | // see if it is legal to inline the callsite. | |||
745 | InlineCost Cost = getInlineCost(CS, Params, GetTTI(*CalledFunction), GetAC, | |||
746 | None, nullptr, nullptr); | |||
747 | if (Cost.isNever()) { | |||
748 | ORE->emit(OptimizationRemark(DEBUG_TYPE"sample-profile", "Not inline", DLoc, BB) | |||
749 | << "incompatible inlining"); | |||
750 | return false; | |||
751 | } | |||
752 | InlineFunctionInfo IFI(nullptr, &GetAC); | |||
753 | if (InlineFunction(CS, IFI)) { | |||
754 | // The call to InlineFunction erases I, so we can't pass it here. | |||
755 | ORE->emit(OptimizationRemark(DEBUG_TYPE"sample-profile", "HotInline", DLoc, BB) | |||
756 | << "inlined hot callee '" << ore::NV("Callee", CalledFunction) | |||
757 | << "' into '" << ore::NV("Caller", BB->getParent()) << "'"); | |||
758 | return true; | |||
759 | } | |||
760 | return false; | |||
761 | } | |||
762 | ||||
763 | /// Iteratively inline hot callsites of a function. | |||
764 | /// | |||
765 | /// Iteratively traverse all callsites of the function \p F, and find if | |||
766 | /// the corresponding inlined instance exists and is hot in profile. If | |||
767 | /// it is hot enough, inline the callsites and adds new callsites of the | |||
768 | /// callee into the caller. If the call is an indirect call, first promote | |||
769 | /// it to direct call. Each indirect call is limited with a single target. | |||
770 | /// | |||
771 | /// \param F function to perform iterative inlining. | |||
772 | /// \param InlinedGUIDs a set to be updated to include all GUIDs that are | |||
773 | /// inlined in the profiled binary. | |||
774 | /// | |||
775 | /// \returns True if there is any inline happened. | |||
776 | bool SampleProfileLoader::inlineHotFunctions( | |||
777 | Function &F, DenseSet<GlobalValue::GUID> &InlinedGUIDs) { | |||
778 | DenseSet<Instruction *> PromotedInsns; | |||
779 | bool Changed = false; | |||
780 | while (true) { | |||
781 | bool LocalChanged = false; | |||
782 | SmallVector<Instruction *, 10> CIS; | |||
783 | for (auto &BB : F) { | |||
784 | bool Hot = false; | |||
785 | SmallVector<Instruction *, 10> Candidates; | |||
786 | for (auto &I : BB.getInstList()) { | |||
787 | const FunctionSamples *FS = nullptr; | |||
788 | if ((isa<CallInst>(I) || isa<InvokeInst>(I)) && | |||
789 | !isa<IntrinsicInst>(I) && (FS = findCalleeFunctionSamples(I))) { | |||
790 | Candidates.push_back(&I); | |||
791 | if (callsiteIsHot(FS, PSI)) | |||
792 | Hot = true; | |||
793 | } | |||
794 | } | |||
795 | if (Hot) { | |||
796 | CIS.insert(CIS.begin(), Candidates.begin(), Candidates.end()); | |||
797 | } | |||
798 | } | |||
799 | for (auto I : CIS) { | |||
800 | Function *CalledFunction = CallSite(I).getCalledFunction(); | |||
801 | // Do not inline recursive calls. | |||
802 | if (CalledFunction == &F) | |||
803 | continue; | |||
804 | if (CallSite(I).isIndirectCall()) { | |||
805 | if (PromotedInsns.count(I)) | |||
806 | continue; | |||
807 | uint64_t Sum; | |||
808 | for (const auto *FS : findIndirectCallFunctionSamples(*I, Sum)) { | |||
809 | if (IsThinLTOPreLink) { | |||
810 | FS->findInlinedFunctions(InlinedGUIDs, F.getParent(), | |||
811 | PSI->getOrCompHotCountThreshold()); | |||
812 | continue; | |||
813 | } | |||
814 | auto CalleeFunctionName = FS->getFuncNameInModule(F.getParent()); | |||
815 | // If it is a recursive call, we do not inline it as it could bloat | |||
816 | // the code exponentially. There is way to better handle this, e.g. | |||
817 | // clone the caller first, and inline the cloned caller if it is | |||
818 | // recursive. As llvm does not inline recursive calls, we will | |||
819 | // simply ignore it instead of handling it explicitly. | |||
820 | if (CalleeFunctionName == F.getName()) | |||
821 | continue; | |||
822 | ||||
823 | const char *Reason = "Callee function not available"; | |||
824 | auto R = SymbolMap.find(CalleeFunctionName); | |||
825 | if (R != SymbolMap.end() && R->getValue() && | |||
826 | !R->getValue()->isDeclaration() && | |||
827 | R->getValue()->getSubprogram() && | |||
828 | isLegalToPromote(CallSite(I), R->getValue(), &Reason)) { | |||
829 | uint64_t C = FS->getEntrySamples(); | |||
830 | Instruction *DI = | |||
831 | pgo::promoteIndirectCall(I, R->getValue(), C, Sum, false, ORE); | |||
832 | Sum -= C; | |||
833 | PromotedInsns.insert(I); | |||
834 | // If profile mismatches, we should not attempt to inline DI. | |||
835 | if ((isa<CallInst>(DI) || isa<InvokeInst>(DI)) && | |||
836 | inlineCallInstruction(DI)) | |||
837 | LocalChanged = true; | |||
838 | } else { | |||
839 | LLVM_DEBUG(dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nFailed to promote indirect call to " << CalleeFunctionName << " because " << Reason << "\n"; } } while (false) | |||
840 | << "\nFailed to promote indirect call to "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nFailed to promote indirect call to " << CalleeFunctionName << " because " << Reason << "\n"; } } while (false) | |||
841 | << CalleeFunctionName << " because " << Reason << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nFailed to promote indirect call to " << CalleeFunctionName << " because " << Reason << "\n"; } } while (false); | |||
842 | } | |||
843 | } | |||
844 | } else if (CalledFunction && CalledFunction->getSubprogram() && | |||
845 | !CalledFunction->isDeclaration()) { | |||
846 | if (inlineCallInstruction(I)) | |||
847 | LocalChanged = true; | |||
848 | } else if (IsThinLTOPreLink) { | |||
849 | findCalleeFunctionSamples(*I)->findInlinedFunctions( | |||
850 | InlinedGUIDs, F.getParent(), PSI->getOrCompHotCountThreshold()); | |||
851 | } | |||
852 | } | |||
853 | if (LocalChanged) { | |||
854 | Changed = true; | |||
855 | } else { | |||
856 | break; | |||
857 | } | |||
858 | } | |||
859 | return Changed; | |||
860 | } | |||
861 | ||||
862 | /// Find equivalence classes for the given block. | |||
863 | /// | |||
864 | /// This finds all the blocks that are guaranteed to execute the same | |||
865 | /// number of times as \p BB1. To do this, it traverses all the | |||
866 | /// descendants of \p BB1 in the dominator or post-dominator tree. | |||
867 | /// | |||
868 | /// A block BB2 will be in the same equivalence class as \p BB1 if | |||
869 | /// the following holds: | |||
870 | /// | |||
871 | /// 1- \p BB1 is a descendant of BB2 in the opposite tree. So, if BB2 | |||
872 | /// is a descendant of \p BB1 in the dominator tree, then BB2 should | |||
873 | /// dominate BB1 in the post-dominator tree. | |||
874 | /// | |||
875 | /// 2- Both BB2 and \p BB1 must be in the same loop. | |||
876 | /// | |||
877 | /// For every block BB2 that meets those two requirements, we set BB2's | |||
878 | /// equivalence class to \p BB1. | |||
879 | /// | |||
880 | /// \param BB1 Block to check. | |||
881 | /// \param Descendants Descendants of \p BB1 in either the dom or pdom tree. | |||
882 | /// \param DomTree Opposite dominator tree. If \p Descendants is filled | |||
883 | /// with blocks from \p BB1's dominator tree, then | |||
884 | /// this is the post-dominator tree, and vice versa. | |||
885 | template <bool IsPostDom> | |||
886 | void SampleProfileLoader::findEquivalencesFor( | |||
887 | BasicBlock *BB1, ArrayRef<BasicBlock *> Descendants, | |||
888 | DominatorTreeBase<BasicBlock, IsPostDom> *DomTree) { | |||
889 | const BasicBlock *EC = EquivalenceClass[BB1]; | |||
890 | uint64_t Weight = BlockWeights[EC]; | |||
891 | for (const auto *BB2 : Descendants) { | |||
892 | bool IsDomParent = DomTree->dominates(BB2, BB1); | |||
893 | bool IsInSameLoop = LI->getLoopFor(BB1) == LI->getLoopFor(BB2); | |||
894 | if (BB1 != BB2 && IsDomParent && IsInSameLoop) { | |||
895 | EquivalenceClass[BB2] = EC; | |||
896 | // If BB2 is visited, then the entire EC should be marked as visited. | |||
897 | if (VisitedBlocks.count(BB2)) { | |||
898 | VisitedBlocks.insert(EC); | |||
899 | } | |||
900 | ||||
901 | // If BB2 is heavier than BB1, make BB2 have the same weight | |||
902 | // as BB1. | |||
903 | // | |||
904 | // Note that we don't worry about the opposite situation here | |||
905 | // (when BB2 is lighter than BB1). We will deal with this | |||
906 | // during the propagation phase. Right now, we just want to | |||
907 | // make sure that BB1 has the largest weight of all the | |||
908 | // members of its equivalence set. | |||
909 | Weight = std::max(Weight, BlockWeights[BB2]); | |||
910 | } | |||
911 | } | |||
912 | if (EC == &EC->getParent()->getEntryBlock()) { | |||
913 | BlockWeights[EC] = Samples->getHeadSamples() + 1; | |||
914 | } else { | |||
915 | BlockWeights[EC] = Weight; | |||
916 | } | |||
917 | } | |||
918 | ||||
919 | /// Find equivalence classes. | |||
920 | /// | |||
921 | /// Since samples may be missing from blocks, we can fill in the gaps by setting | |||
922 | /// the weights of all the blocks in the same equivalence class to the same | |||
923 | /// weight. To compute the concept of equivalence, we use dominance and loop | |||
924 | /// information. Two blocks B1 and B2 are in the same equivalence class if B1 | |||
925 | /// dominates B2, B2 post-dominates B1 and both are in the same loop. | |||
926 | /// | |||
927 | /// \param F The function to query. | |||
928 | void SampleProfileLoader::findEquivalenceClasses(Function &F) { | |||
929 | SmallVector<BasicBlock *, 8> DominatedBBs; | |||
930 | LLVM_DEBUG(dbgs() << "\nBlock equivalence classes\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nBlock equivalence classes\n" ; } } while (false); | |||
931 | // Find equivalence sets based on dominance and post-dominance information. | |||
932 | for (auto &BB : F) { | |||
933 | BasicBlock *BB1 = &BB; | |||
934 | ||||
935 | // Compute BB1's equivalence class once. | |||
936 | if (EquivalenceClass.count(BB1)) { | |||
937 | LLVM_DEBUG(printBlockEquivalence(dbgs(), BB1))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { printBlockEquivalence(dbgs(), BB1); } } while (false); | |||
938 | continue; | |||
939 | } | |||
940 | ||||
941 | // By default, blocks are in their own equivalence class. | |||
942 | EquivalenceClass[BB1] = BB1; | |||
943 | ||||
944 | // Traverse all the blocks dominated by BB1. We are looking for | |||
945 | // every basic block BB2 such that: | |||
946 | // | |||
947 | // 1- BB1 dominates BB2. | |||
948 | // 2- BB2 post-dominates BB1. | |||
949 | // 3- BB1 and BB2 are in the same loop nest. | |||
950 | // | |||
951 | // If all those conditions hold, it means that BB2 is executed | |||
952 | // as many times as BB1, so they are placed in the same equivalence | |||
953 | // class by making BB2's equivalence class be BB1. | |||
954 | DominatedBBs.clear(); | |||
955 | DT->getDescendants(BB1, DominatedBBs); | |||
956 | findEquivalencesFor(BB1, DominatedBBs, PDT.get()); | |||
957 | ||||
958 | LLVM_DEBUG(printBlockEquivalence(dbgs(), BB1))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { printBlockEquivalence(dbgs(), BB1); } } while (false); | |||
959 | } | |||
960 | ||||
961 | // Assign weights to equivalence classes. | |||
962 | // | |||
963 | // All the basic blocks in the same equivalence class will execute | |||
964 | // the same number of times. Since we know that the head block in | |||
965 | // each equivalence class has the largest weight, assign that weight | |||
966 | // to all the blocks in that equivalence class. | |||
967 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nAssign the same weight to all blocks in the same class\n" ; } } while (false) | |||
968 | dbgs() << "\nAssign the same weight to all blocks in the same class\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nAssign the same weight to all blocks in the same class\n" ; } } while (false); | |||
969 | for (auto &BI : F) { | |||
970 | const BasicBlock *BB = &BI; | |||
971 | const BasicBlock *EquivBB = EquivalenceClass[BB]; | |||
972 | if (BB != EquivBB) | |||
973 | BlockWeights[BB] = BlockWeights[EquivBB]; | |||
974 | LLVM_DEBUG(printBlockWeight(dbgs(), BB))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { printBlockWeight(dbgs(), BB); } } while (false); | |||
975 | } | |||
976 | } | |||
977 | ||||
978 | /// Visit the given edge to decide if it has a valid weight. | |||
979 | /// | |||
980 | /// If \p E has not been visited before, we copy to \p UnknownEdge | |||
981 | /// and increment the count of unknown edges. | |||
982 | /// | |||
983 | /// \param E Edge to visit. | |||
984 | /// \param NumUnknownEdges Current number of unknown edges. | |||
985 | /// \param UnknownEdge Set if E has not been visited before. | |||
986 | /// | |||
987 | /// \returns E's weight, if known. Otherwise, return 0. | |||
988 | uint64_t SampleProfileLoader::visitEdge(Edge E, unsigned *NumUnknownEdges, | |||
989 | Edge *UnknownEdge) { | |||
990 | if (!VisitedEdges.count(E)) { | |||
991 | (*NumUnknownEdges)++; | |||
992 | *UnknownEdge = E; | |||
993 | return 0; | |||
994 | } | |||
995 | ||||
996 | return EdgeWeights[E]; | |||
997 | } | |||
998 | ||||
999 | /// Propagate weights through incoming/outgoing edges. | |||
1000 | /// | |||
1001 | /// If the weight of a basic block is known, and there is only one edge | |||
1002 | /// with an unknown weight, we can calculate the weight of that edge. | |||
1003 | /// | |||
1004 | /// Similarly, if all the edges have a known count, we can calculate the | |||
1005 | /// count of the basic block, if needed. | |||
1006 | /// | |||
1007 | /// \param F Function to process. | |||
1008 | /// \param UpdateBlockCount Whether we should update basic block counts that | |||
1009 | /// has already been annotated. | |||
1010 | /// | |||
1011 | /// \returns True if new weights were assigned to edges or blocks. | |||
1012 | bool SampleProfileLoader::propagateThroughEdges(Function &F, | |||
1013 | bool UpdateBlockCount) { | |||
1014 | bool Changed = false; | |||
1015 | LLVM_DEBUG(dbgs() << "\nPropagation through edges\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nPropagation through edges\n" ; } } while (false); | |||
1016 | for (const auto &BI : F) { | |||
1017 | const BasicBlock *BB = &BI; | |||
1018 | const BasicBlock *EC = EquivalenceClass[BB]; | |||
1019 | ||||
1020 | // Visit all the predecessor and successor edges to determine | |||
1021 | // which ones have a weight assigned already. Note that it doesn't | |||
1022 | // matter that we only keep track of a single unknown edge. The | |||
1023 | // only case we are interested in handling is when only a single | |||
1024 | // edge is unknown (see setEdgeOrBlockWeight). | |||
1025 | for (unsigned i = 0; i < 2; i++) { | |||
1026 | uint64_t TotalWeight = 0; | |||
1027 | unsigned NumUnknownEdges = 0, NumTotalEdges = 0; | |||
1028 | Edge UnknownEdge, SelfReferentialEdge, SingleEdge; | |||
1029 | ||||
1030 | if (i == 0) { | |||
1031 | // First, visit all predecessor edges. | |||
1032 | NumTotalEdges = Predecessors[BB].size(); | |||
1033 | for (auto *Pred : Predecessors[BB]) { | |||
1034 | Edge E = std::make_pair(Pred, BB); | |||
1035 | TotalWeight += visitEdge(E, &NumUnknownEdges, &UnknownEdge); | |||
1036 | if (E.first == E.second) | |||
1037 | SelfReferentialEdge = E; | |||
1038 | } | |||
1039 | if (NumTotalEdges == 1) { | |||
1040 | SingleEdge = std::make_pair(Predecessors[BB][0], BB); | |||
1041 | } | |||
1042 | } else { | |||
1043 | // On the second round, visit all successor edges. | |||
1044 | NumTotalEdges = Successors[BB].size(); | |||
1045 | for (auto *Succ : Successors[BB]) { | |||
1046 | Edge E = std::make_pair(BB, Succ); | |||
1047 | TotalWeight += visitEdge(E, &NumUnknownEdges, &UnknownEdge); | |||
1048 | } | |||
1049 | if (NumTotalEdges == 1) { | |||
1050 | SingleEdge = std::make_pair(BB, Successors[BB][0]); | |||
1051 | } | |||
1052 | } | |||
1053 | ||||
1054 | // After visiting all the edges, there are three cases that we | |||
1055 | // can handle immediately: | |||
1056 | // | |||
1057 | // - All the edge weights are known (i.e., NumUnknownEdges == 0). | |||
1058 | // In this case, we simply check that the sum of all the edges | |||
1059 | // is the same as BB's weight. If not, we change BB's weight | |||
1060 | // to match. Additionally, if BB had not been visited before, | |||
1061 | // we mark it visited. | |||
1062 | // | |||
1063 | // - Only one edge is unknown and BB has already been visited. | |||
1064 | // In this case, we can compute the weight of the edge by | |||
1065 | // subtracting the total block weight from all the known | |||
1066 | // edge weights. If the edges weight more than BB, then the | |||
1067 | // edge of the last remaining edge is set to zero. | |||
1068 | // | |||
1069 | // - There exists a self-referential edge and the weight of BB is | |||
1070 | // known. In this case, this edge can be based on BB's weight. | |||
1071 | // We add up all the other known edges and set the weight on | |||
1072 | // the self-referential edge as we did in the previous case. | |||
1073 | // | |||
1074 | // In any other case, we must continue iterating. Eventually, | |||
1075 | // all edges will get a weight, or iteration will stop when | |||
1076 | // it reaches SampleProfileMaxPropagateIterations. | |||
1077 | if (NumUnknownEdges <= 1) { | |||
1078 | uint64_t &BBWeight = BlockWeights[EC]; | |||
1079 | if (NumUnknownEdges == 0) { | |||
1080 | if (!VisitedBlocks.count(EC)) { | |||
1081 | // If we already know the weight of all edges, the weight of the | |||
1082 | // basic block can be computed. It should be no larger than the sum | |||
1083 | // of all edge weights. | |||
1084 | if (TotalWeight > BBWeight) { | |||
1085 | BBWeight = TotalWeight; | |||
1086 | Changed = true; | |||
1087 | LLVM_DEBUG(dbgs() << "All edge weights for " << BB->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "All edge weights for " << BB->getName() << " known. Set weight for block: " ; printBlockWeight(dbgs(), BB);; } } while (false) | |||
1088 | << " known. Set weight for block: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "All edge weights for " << BB->getName() << " known. Set weight for block: " ; printBlockWeight(dbgs(), BB);; } } while (false) | |||
1089 | printBlockWeight(dbgs(), BB);)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "All edge weights for " << BB->getName() << " known. Set weight for block: " ; printBlockWeight(dbgs(), BB);; } } while (false); | |||
1090 | } | |||
1091 | } else if (NumTotalEdges == 1 && | |||
1092 | EdgeWeights[SingleEdge] < BlockWeights[EC]) { | |||
1093 | // If there is only one edge for the visited basic block, use the | |||
1094 | // block weight to adjust edge weight if edge weight is smaller. | |||
1095 | EdgeWeights[SingleEdge] = BlockWeights[EC]; | |||
1096 | Changed = true; | |||
1097 | } | |||
1098 | } else if (NumUnknownEdges == 1 && VisitedBlocks.count(EC)) { | |||
1099 | // If there is a single unknown edge and the block has been | |||
1100 | // visited, then we can compute E's weight. | |||
1101 | if (BBWeight >= TotalWeight) | |||
1102 | EdgeWeights[UnknownEdge] = BBWeight - TotalWeight; | |||
1103 | else | |||
1104 | EdgeWeights[UnknownEdge] = 0; | |||
1105 | const BasicBlock *OtherEC; | |||
1106 | if (i == 0) | |||
1107 | OtherEC = EquivalenceClass[UnknownEdge.first]; | |||
1108 | else | |||
1109 | OtherEC = EquivalenceClass[UnknownEdge.second]; | |||
1110 | // Edge weights should never exceed the BB weights it connects. | |||
1111 | if (VisitedBlocks.count(OtherEC) && | |||
1112 | EdgeWeights[UnknownEdge] > BlockWeights[OtherEC]) | |||
1113 | EdgeWeights[UnknownEdge] = BlockWeights[OtherEC]; | |||
1114 | VisitedEdges.insert(UnknownEdge); | |||
1115 | Changed = true; | |||
1116 | LLVM_DEBUG(dbgs() << "Set weight for edge: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Set weight for edge: " ; printEdgeWeight(dbgs(), UnknownEdge); } } while (false) | |||
1117 | printEdgeWeight(dbgs(), UnknownEdge))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Set weight for edge: " ; printEdgeWeight(dbgs(), UnknownEdge); } } while (false); | |||
1118 | } | |||
1119 | } else if (VisitedBlocks.count(EC) && BlockWeights[EC] == 0) { | |||
1120 | // If a block Weights 0, all its in/out edges should weight 0. | |||
1121 | if (i == 0) { | |||
1122 | for (auto *Pred : Predecessors[BB]) { | |||
1123 | Edge E = std::make_pair(Pred, BB); | |||
1124 | EdgeWeights[E] = 0; | |||
1125 | VisitedEdges.insert(E); | |||
1126 | } | |||
1127 | } else { | |||
1128 | for (auto *Succ : Successors[BB]) { | |||
1129 | Edge E = std::make_pair(BB, Succ); | |||
1130 | EdgeWeights[E] = 0; | |||
1131 | VisitedEdges.insert(E); | |||
1132 | } | |||
1133 | } | |||
1134 | } else if (SelfReferentialEdge.first && VisitedBlocks.count(EC)) { | |||
1135 | uint64_t &BBWeight = BlockWeights[BB]; | |||
1136 | // We have a self-referential edge and the weight of BB is known. | |||
1137 | if (BBWeight >= TotalWeight) | |||
1138 | EdgeWeights[SelfReferentialEdge] = BBWeight - TotalWeight; | |||
1139 | else | |||
1140 | EdgeWeights[SelfReferentialEdge] = 0; | |||
1141 | VisitedEdges.insert(SelfReferentialEdge); | |||
1142 | Changed = true; | |||
1143 | LLVM_DEBUG(dbgs() << "Set self-referential edge weight to: ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Set self-referential edge weight to: " ; printEdgeWeight(dbgs(), SelfReferentialEdge); } } while (false ) | |||
1144 | printEdgeWeight(dbgs(), SelfReferentialEdge))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Set self-referential edge weight to: " ; printEdgeWeight(dbgs(), SelfReferentialEdge); } } while (false ); | |||
1145 | } | |||
1146 | if (UpdateBlockCount && !VisitedBlocks.count(EC) && TotalWeight > 0) { | |||
1147 | BlockWeights[EC] = TotalWeight; | |||
1148 | VisitedBlocks.insert(EC); | |||
1149 | Changed = true; | |||
1150 | } | |||
1151 | } | |||
1152 | } | |||
1153 | ||||
1154 | return Changed; | |||
1155 | } | |||
1156 | ||||
1157 | /// Build in/out edge lists for each basic block in the CFG. | |||
1158 | /// | |||
1159 | /// We are interested in unique edges. If a block B1 has multiple | |||
1160 | /// edges to another block B2, we only add a single B1->B2 edge. | |||
1161 | void SampleProfileLoader::buildEdges(Function &F) { | |||
1162 | for (auto &BI : F) { | |||
1163 | BasicBlock *B1 = &BI; | |||
1164 | ||||
1165 | // Add predecessors for B1. | |||
1166 | SmallPtrSet<BasicBlock *, 16> Visited; | |||
1167 | if (!Predecessors[B1].empty()) | |||
1168 | llvm_unreachable("Found a stale predecessors list in a basic block.")::llvm::llvm_unreachable_internal("Found a stale predecessors list in a basic block." , "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 1168); | |||
1169 | for (pred_iterator PI = pred_begin(B1), PE = pred_end(B1); PI != PE; ++PI) { | |||
1170 | BasicBlock *B2 = *PI; | |||
1171 | if (Visited.insert(B2).second) | |||
1172 | Predecessors[B1].push_back(B2); | |||
1173 | } | |||
1174 | ||||
1175 | // Add successors for B1. | |||
1176 | Visited.clear(); | |||
1177 | if (!Successors[B1].empty()) | |||
1178 | llvm_unreachable("Found a stale successors list in a basic block.")::llvm::llvm_unreachable_internal("Found a stale successors list in a basic block." , "/build/llvm-toolchain-snapshot-8~svn350071/lib/Transforms/IPO/SampleProfile.cpp" , 1178); | |||
1179 | for (succ_iterator SI = succ_begin(B1), SE = succ_end(B1); SI != SE; ++SI) { | |||
1180 | BasicBlock *B2 = *SI; | |||
1181 | if (Visited.insert(B2).second) | |||
1182 | Successors[B1].push_back(B2); | |||
1183 | } | |||
1184 | } | |||
1185 | } | |||
1186 | ||||
1187 | /// Returns the sorted CallTargetMap \p M by count in descending order. | |||
1188 | static SmallVector<InstrProfValueData, 2> SortCallTargets( | |||
1189 | const SampleRecord::CallTargetMap &M) { | |||
1190 | SmallVector<InstrProfValueData, 2> R; | |||
1191 | for (auto I = M.begin(); I != M.end(); ++I) | |||
1192 | R.push_back({FunctionSamples::getGUID(I->getKey()), I->getValue()}); | |||
1193 | llvm::sort(R, [](const InstrProfValueData &L, const InstrProfValueData &R) { | |||
1194 | if (L.Count == R.Count) | |||
1195 | return L.Value > R.Value; | |||
1196 | else | |||
1197 | return L.Count > R.Count; | |||
1198 | }); | |||
1199 | return R; | |||
1200 | } | |||
1201 | ||||
1202 | /// Propagate weights into edges | |||
1203 | /// | |||
1204 | /// The following rules are applied to every block BB in the CFG: | |||
1205 | /// | |||
1206 | /// - If BB has a single predecessor/successor, then the weight | |||
1207 | /// of that edge is the weight of the block. | |||
1208 | /// | |||
1209 | /// - If all incoming or outgoing edges are known except one, and the | |||
1210 | /// weight of the block is already known, the weight of the unknown | |||
1211 | /// edge will be the weight of the block minus the sum of all the known | |||
1212 | /// edges. If the sum of all the known edges is larger than BB's weight, | |||
1213 | /// we set the unknown edge weight to zero. | |||
1214 | /// | |||
1215 | /// - If there is a self-referential edge, and the weight of the block is | |||
1216 | /// known, the weight for that edge is set to the weight of the block | |||
1217 | /// minus the weight of the other incoming edges to that block (if | |||
1218 | /// known). | |||
1219 | void SampleProfileLoader::propagateWeights(Function &F) { | |||
1220 | bool Changed = true; | |||
1221 | unsigned I = 0; | |||
1222 | ||||
1223 | // If BB weight is larger than its corresponding loop's header BB weight, | |||
1224 | // use the BB weight to replace the loop header BB weight. | |||
1225 | for (auto &BI : F) { | |||
1226 | BasicBlock *BB = &BI; | |||
1227 | Loop *L = LI->getLoopFor(BB); | |||
1228 | if (!L) { | |||
1229 | continue; | |||
1230 | } | |||
1231 | BasicBlock *Header = L->getHeader(); | |||
1232 | if (Header && BlockWeights[BB] > BlockWeights[Header]) { | |||
1233 | BlockWeights[Header] = BlockWeights[BB]; | |||
1234 | } | |||
1235 | } | |||
1236 | ||||
1237 | // Before propagation starts, build, for each block, a list of | |||
1238 | // unique predecessors and successors. This is necessary to handle | |||
1239 | // identical edges in multiway branches. Since we visit all blocks and all | |||
1240 | // edges of the CFG, it is cleaner to build these lists once at the start | |||
1241 | // of the pass. | |||
1242 | buildEdges(F); | |||
1243 | ||||
1244 | // Propagate until we converge or we go past the iteration limit. | |||
1245 | while (Changed && I++ < SampleProfileMaxPropagateIterations) { | |||
1246 | Changed = propagateThroughEdges(F, false); | |||
1247 | } | |||
1248 | ||||
1249 | // The first propagation propagates BB counts from annotated BBs to unknown | |||
1250 | // BBs. The 2nd propagation pass resets edges weights, and use all BB weights | |||
1251 | // to propagate edge weights. | |||
1252 | VisitedEdges.clear(); | |||
1253 | Changed = true; | |||
1254 | while (Changed && I++ < SampleProfileMaxPropagateIterations) { | |||
1255 | Changed = propagateThroughEdges(F, false); | |||
1256 | } | |||
1257 | ||||
1258 | // The 3rd propagation pass allows adjust annotated BB weights that are | |||
1259 | // obviously wrong. | |||
1260 | Changed = true; | |||
1261 | while (Changed && I++ < SampleProfileMaxPropagateIterations) { | |||
1262 | Changed = propagateThroughEdges(F, true); | |||
1263 | } | |||
1264 | ||||
1265 | // Generate MD_prof metadata for every branch instruction using the | |||
1266 | // edge weights computed during propagation. | |||
1267 | LLVM_DEBUG(dbgs() << "\nPropagation complete. Setting branch weights\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nPropagation complete. Setting branch weights\n" ; } } while (false); | |||
1268 | LLVMContext &Ctx = F.getContext(); | |||
1269 | MDBuilder MDB(Ctx); | |||
1270 | for (auto &BI : F) { | |||
1271 | BasicBlock *BB = &BI; | |||
1272 | ||||
1273 | if (BlockWeights[BB]) { | |||
1274 | for (auto &I : BB->getInstList()) { | |||
1275 | if (!isa<CallInst>(I) && !isa<InvokeInst>(I)) | |||
1276 | continue; | |||
1277 | CallSite CS(&I); | |||
1278 | if (!CS.getCalledFunction()) { | |||
1279 | const DebugLoc &DLoc = I.getDebugLoc(); | |||
1280 | if (!DLoc) | |||
1281 | continue; | |||
1282 | const DILocation *DIL = DLoc; | |||
1283 | uint32_t LineOffset = FunctionSamples::getOffset(DIL); | |||
1284 | uint32_t Discriminator = DIL->getBaseDiscriminator(); | |||
1285 | ||||
1286 | const FunctionSamples *FS = findFunctionSamples(I); | |||
1287 | if (!FS) | |||
1288 | continue; | |||
1289 | auto T = FS->findCallTargetMapAt(LineOffset, Discriminator); | |||
1290 | if (!T || T.get().empty()) | |||
1291 | continue; | |||
1292 | SmallVector<InstrProfValueData, 2> SortedCallTargets = | |||
1293 | SortCallTargets(T.get()); | |||
1294 | uint64_t Sum; | |||
1295 | findIndirectCallFunctionSamples(I, Sum); | |||
1296 | annotateValueSite(*I.getParent()->getParent()->getParent(), I, | |||
1297 | SortedCallTargets, Sum, IPVK_IndirectCallTarget, | |||
1298 | SortedCallTargets.size()); | |||
1299 | } else if (!dyn_cast<IntrinsicInst>(&I)) { | |||
1300 | SmallVector<uint32_t, 1> Weights; | |||
1301 | Weights.push_back(BlockWeights[BB]); | |||
1302 | I.setMetadata(LLVMContext::MD_prof, MDB.createBranchWeights(Weights)); | |||
1303 | } | |||
1304 | } | |||
1305 | } | |||
1306 | Instruction *TI = BB->getTerminator(); | |||
1307 | if (TI->getNumSuccessors() == 1) | |||
1308 | continue; | |||
1309 | if (!isa<BranchInst>(TI) && !isa<SwitchInst>(TI)) | |||
1310 | continue; | |||
1311 | ||||
1312 | DebugLoc BranchLoc = TI->getDebugLoc(); | |||
1313 | LLVM_DEBUG(dbgs() << "\nGetting weights for branch at line "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nGetting weights for branch at line " << ((BranchLoc) ? Twine(BranchLoc.getLine()) : Twine("<UNKNOWN LOCATION>" )) << ".\n"; } } while (false) | |||
1314 | << ((BranchLoc) ? Twine(BranchLoc.getLine())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nGetting weights for branch at line " << ((BranchLoc) ? Twine(BranchLoc.getLine()) : Twine("<UNKNOWN LOCATION>" )) << ".\n"; } } while (false) | |||
1315 | : Twine("<UNKNOWN LOCATION>"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nGetting weights for branch at line " << ((BranchLoc) ? Twine(BranchLoc.getLine()) : Twine("<UNKNOWN LOCATION>" )) << ".\n"; } } while (false) | |||
1316 | << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\nGetting weights for branch at line " << ((BranchLoc) ? Twine(BranchLoc.getLine()) : Twine("<UNKNOWN LOCATION>" )) << ".\n"; } } while (false); | |||
1317 | SmallVector<uint32_t, 4> Weights; | |||
1318 | uint32_t MaxWeight = 0; | |||
1319 | Instruction *MaxDestInst; | |||
1320 | for (unsigned I = 0; I < TI->getNumSuccessors(); ++I) { | |||
1321 | BasicBlock *Succ = TI->getSuccessor(I); | |||
1322 | Edge E = std::make_pair(BB, Succ); | |||
1323 | uint64_t Weight = EdgeWeights[E]; | |||
1324 | LLVM_DEBUG(dbgs() << "\t"; printEdgeWeight(dbgs(), E))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "\t"; printEdgeWeight(dbgs (), E); } } while (false); | |||
1325 | // Use uint32_t saturated arithmetic to adjust the incoming weights, | |||
1326 | // if needed. Sample counts in profiles are 64-bit unsigned values, | |||
1327 | // but internally branch weights are expressed as 32-bit values. | |||
1328 | if (Weight > std::numeric_limits<uint32_t>::max()) { | |||
1329 | LLVM_DEBUG(dbgs() << " (saturated due to uint32_t overflow)")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << " (saturated due to uint32_t overflow)" ; } } while (false); | |||
1330 | Weight = std::numeric_limits<uint32_t>::max(); | |||
1331 | } | |||
1332 | // Weight is added by one to avoid propagation errors introduced by | |||
1333 | // 0 weights. | |||
1334 | Weights.push_back(static_cast<uint32_t>(Weight + 1)); | |||
1335 | if (Weight != 0) { | |||
1336 | if (Weight > MaxWeight) { | |||
1337 | MaxWeight = Weight; | |||
1338 | MaxDestInst = Succ->getFirstNonPHIOrDbgOrLifetime(); | |||
1339 | } | |||
1340 | } | |||
1341 | } | |||
1342 | ||||
1343 | uint64_t TempWeight; | |||
1344 | // Only set weights if there is at least one non-zero weight. | |||
1345 | // In any other case, let the analyzer set weights. | |||
1346 | // Do not set weights if the weights are present. In ThinLTO, the profile | |||
1347 | // annotation is done twice. If the first annotation already set the | |||
1348 | // weights, the second pass does not need to set it. | |||
1349 | if (MaxWeight > 0 && !TI->extractProfTotalWeight(TempWeight)) { | |||
1350 | LLVM_DEBUG(dbgs() << "SUCCESS. Found non-zero weights.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "SUCCESS. Found non-zero weights.\n" ; } } while (false); | |||
1351 | TI->setMetadata(LLVMContext::MD_prof, | |||
1352 | MDB.createBranchWeights(Weights)); | |||
1353 | ORE->emit([&]() { | |||
1354 | return OptimizationRemark(DEBUG_TYPE"sample-profile", "PopularDest", MaxDestInst) | |||
1355 | << "most popular destination for conditional branches at " | |||
1356 | << ore::NV("CondBranchesLoc", BranchLoc); | |||
1357 | }); | |||
1358 | } else { | |||
1359 | LLVM_DEBUG(dbgs() << "SKIPPED. All branch weights are zero.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "SKIPPED. All branch weights are zero.\n" ; } } while (false); | |||
1360 | } | |||
1361 | } | |||
1362 | } | |||
1363 | ||||
1364 | /// Get the line number for the function header. | |||
1365 | /// | |||
1366 | /// This looks up function \p F in the current compilation unit and | |||
1367 | /// retrieves the line number where the function is defined. This is | |||
1368 | /// line 0 for all the samples read from the profile file. Every line | |||
1369 | /// number is relative to this line. | |||
1370 | /// | |||
1371 | /// \param F Function object to query. | |||
1372 | /// | |||
1373 | /// \returns the line number where \p F is defined. If it returns 0, | |||
1374 | /// it means that there is no debug information available for \p F. | |||
1375 | unsigned SampleProfileLoader::getFunctionLoc(Function &F) { | |||
1376 | if (DISubprogram *S = F.getSubprogram()) | |||
1377 | return S->getLine(); | |||
1378 | ||||
1379 | if (NoWarnSampleUnused) | |||
1380 | return 0; | |||
1381 | ||||
1382 | // If the start of \p F is missing, emit a diagnostic to inform the user | |||
1383 | // about the missed opportunity. | |||
1384 | F.getContext().diagnose(DiagnosticInfoSampleProfile( | |||
1385 | "No debug information found in function " + F.getName() + | |||
1386 | ": Function profile not used", | |||
1387 | DS_Warning)); | |||
1388 | return 0; | |||
1389 | } | |||
1390 | ||||
1391 | void SampleProfileLoader::computeDominanceAndLoopInfo(Function &F) { | |||
1392 | DT.reset(new DominatorTree); | |||
1393 | DT->recalculate(F); | |||
1394 | ||||
1395 | PDT.reset(new PostDominatorTree(F)); | |||
1396 | ||||
1397 | LI.reset(new LoopInfo); | |||
1398 | LI->analyze(*DT); | |||
1399 | } | |||
1400 | ||||
1401 | /// Generate branch weight metadata for all branches in \p F. | |||
1402 | /// | |||
1403 | /// Branch weights are computed out of instruction samples using a | |||
1404 | /// propagation heuristic. Propagation proceeds in 3 phases: | |||
1405 | /// | |||
1406 | /// 1- Assignment of block weights. All the basic blocks in the function | |||
1407 | /// are initial assigned the same weight as their most frequently | |||
1408 | /// executed instruction. | |||
1409 | /// | |||
1410 | /// 2- Creation of equivalence classes. Since samples may be missing from | |||
1411 | /// blocks, we can fill in the gaps by setting the weights of all the | |||
1412 | /// blocks in the same equivalence class to the same weight. To compute | |||
1413 | /// the concept of equivalence, we use dominance and loop information. | |||
1414 | /// Two blocks B1 and B2 are in the same equivalence class if B1 | |||
1415 | /// dominates B2, B2 post-dominates B1 and both are in the same loop. | |||
1416 | /// | |||
1417 | /// 3- Propagation of block weights into edges. This uses a simple | |||
1418 | /// propagation heuristic. The following rules are applied to every | |||
1419 | /// block BB in the CFG: | |||
1420 | /// | |||
1421 | /// - If BB has a single predecessor/successor, then the weight | |||
1422 | /// of that edge is the weight of the block. | |||
1423 | /// | |||
1424 | /// - If all the edges are known except one, and the weight of the | |||
1425 | /// block is already known, the weight of the unknown edge will | |||
1426 | /// be the weight of the block minus the sum of all the known | |||
1427 | /// edges. If the sum of all the known edges is larger than BB's weight, | |||
1428 | /// we set the unknown edge weight to zero. | |||
1429 | /// | |||
1430 | /// - If there is a self-referential edge, and the weight of the block is | |||
1431 | /// known, the weight for that edge is set to the weight of the block | |||
1432 | /// minus the weight of the other incoming edges to that block (if | |||
1433 | /// known). | |||
1434 | /// | |||
1435 | /// Since this propagation is not guaranteed to finalize for every CFG, we | |||
1436 | /// only allow it to proceed for a limited number of iterations (controlled | |||
1437 | /// by -sample-profile-max-propagate-iterations). | |||
1438 | /// | |||
1439 | /// FIXME: Try to replace this propagation heuristic with a scheme | |||
1440 | /// that is guaranteed to finalize. A work-list approach similar to | |||
1441 | /// the standard value propagation algorithm used by SSA-CCP might | |||
1442 | /// work here. | |||
1443 | /// | |||
1444 | /// Once all the branch weights are computed, we emit the MD_prof | |||
1445 | /// metadata on BB using the computed values for each of its branches. | |||
1446 | /// | |||
1447 | /// \param F The function to query. | |||
1448 | /// | |||
1449 | /// \returns true if \p F was modified. Returns false, otherwise. | |||
1450 | bool SampleProfileLoader::emitAnnotations(Function &F) { | |||
1451 | bool Changed = false; | |||
1452 | ||||
1453 | if (getFunctionLoc(F) == 0) | |||
1454 | return false; | |||
1455 | ||||
1456 | LLVM_DEBUG(dbgs() << "Line number for the first instruction in "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Line number for the first instruction in " << F.getName() << ": " << getFunctionLoc(F ) << "\n"; } } while (false) | |||
1457 | << F.getName() << ": " << getFunctionLoc(F) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("sample-profile")) { dbgs() << "Line number for the first instruction in " << F.getName() << ": " << getFunctionLoc(F ) << "\n"; } } while (false); | |||
1458 | ||||
1459 | DenseSet<GlobalValue::GUID> InlinedGUIDs; | |||
1460 | Changed |= inlineHotFunctions(F, InlinedGUIDs); | |||
1461 | ||||
1462 | // Compute basic block weights. | |||
1463 | Changed |= computeBlockWeights(F); | |||
1464 | ||||
1465 | if (Changed) { | |||
1466 | // Add an entry count to the function using the samples gathered at the | |||
1467 | // function entry. | |||
1468 | // Sets the GUIDs that are inlined in the profiled binary. This is used | |||
1469 | // for ThinLink to make correct liveness analysis, and also make the IR | |||
1470 | // match the profiled binary before annotation. | |||
1471 | F.setEntryCount( | |||
1472 | ProfileCount(Samples->getHeadSamples() + 1, Function::PCT_Real), | |||
1473 | &InlinedGUIDs); | |||
1474 | ||||
1475 | // Compute dominance and loop info needed for propagation. | |||
1476 | computeDominanceAndLoopInfo(F); | |||
1477 | ||||
1478 | // Find equivalence classes. | |||
1479 | findEquivalenceClasses(F); | |||
1480 | ||||
1481 | // Propagate weights to all edges. | |||
1482 | propagateWeights(F); | |||
1483 | } | |||
1484 | ||||
1485 | // If coverage checking was requested, compute it now. | |||
1486 | if (SampleProfileRecordCoverage) { | |||
1487 | unsigned Used = CoverageTracker.countUsedRecords(Samples, PSI); | |||
1488 | unsigned Total = CoverageTracker.countBodyRecords(Samples, PSI); | |||
1489 | unsigned Coverage = CoverageTracker.computeCoverage(Used, Total); | |||
1490 | if (Coverage < SampleProfileRecordCoverage) { | |||
1491 | F.getContext().diagnose(DiagnosticInfoSampleProfile( | |||
1492 | F.getSubprogram()->getFilename(), getFunctionLoc(F), | |||
1493 | Twine(Used) + " of " + Twine(Total) + " available profile records (" + | |||
1494 | Twine(Coverage) + "%) were applied", | |||
1495 | DS_Warning)); | |||
1496 | } | |||
1497 | } | |||
1498 | ||||
1499 | if (SampleProfileSampleCoverage) { | |||
1500 | uint64_t Used = CoverageTracker.getTotalUsedSamples(); | |||
1501 | uint64_t Total = CoverageTracker.countBodySamples(Samples, PSI); | |||
1502 | unsigned Coverage = CoverageTracker.computeCoverage(Used, Total); | |||
1503 | if (Coverage < SampleProfileSampleCoverage) { | |||
1504 | F.getContext().diagnose(DiagnosticInfoSampleProfile( | |||
1505 | F.getSubprogram()->getFilename(), getFunctionLoc(F), | |||
1506 | Twine(Used) + " of " + Twine(Total) + " available profile samples (" + | |||
1507 | Twine(Coverage) + "%) were applied", | |||
1508 | DS_Warning)); | |||
1509 | } | |||
1510 | } | |||
1511 | return Changed; | |||
1512 | } | |||
1513 | ||||
1514 | char SampleProfileLoaderLegacyPass::ID = 0; | |||
1515 | ||||
1516 | INITIALIZE_PASS_BEGIN(SampleProfileLoaderLegacyPass, "sample-profile",static void *initializeSampleProfileLoaderLegacyPassPassOnce( PassRegistry &Registry) { | |||
1517 | "Sample Profile loader", false, false)static void *initializeSampleProfileLoaderLegacyPassPassOnce( PassRegistry &Registry) { | |||
1518 | INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)initializeAssumptionCacheTrackerPass(Registry); | |||
1519 | INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)initializeTargetTransformInfoWrapperPassPass(Registry); | |||
1520 | INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)initializeProfileSummaryInfoWrapperPassPass(Registry); | |||
1521 | INITIALIZE_PASS_END(SampleProfileLoaderLegacyPass, "sample-profile",PassInfo *PI = new PassInfo( "Sample Profile loader", "sample-profile" , &SampleProfileLoaderLegacyPass::ID, PassInfo::NormalCtor_t (callDefaultCtor<SampleProfileLoaderLegacyPass>), false , false); Registry.registerPass(*PI, true); return PI; } static llvm::once_flag InitializeSampleProfileLoaderLegacyPassPassFlag ; void llvm::initializeSampleProfileLoaderLegacyPassPass(PassRegistry &Registry) { llvm::call_once(InitializeSampleProfileLoaderLegacyPassPassFlag , initializeSampleProfileLoaderLegacyPassPassOnce, std::ref(Registry )); } | |||
1522 | "Sample Profile loader", false, false)PassInfo *PI = new PassInfo( "Sample Profile loader", "sample-profile" , &SampleProfileLoaderLegacyPass::ID, PassInfo::NormalCtor_t (callDefaultCtor<SampleProfileLoaderLegacyPass>), false , false); Registry.registerPass(*PI, true); return PI; } static llvm::once_flag InitializeSampleProfileLoaderLegacyPassPassFlag ; void llvm::initializeSampleProfileLoaderLegacyPassPass(PassRegistry &Registry) { llvm::call_once(InitializeSampleProfileLoaderLegacyPassPassFlag , initializeSampleProfileLoaderLegacyPassPassOnce, std::ref(Registry )); } | |||
1523 | ||||
1524 | bool SampleProfileLoader::doInitialization(Module &M) { | |||
1525 | auto &Ctx = M.getContext(); | |||
1526 | auto ReaderOrErr = SampleProfileReader::create(Filename, Ctx); | |||
1527 | if (std::error_code EC = ReaderOrErr.getError()) { | |||
1528 | std::string Msg = "Could not open profile: " + EC.message(); | |||
1529 | Ctx.diagnose(DiagnosticInfoSampleProfile(Filename, Msg)); | |||
1530 | return false; | |||
1531 | } | |||
1532 | Reader = std::move(ReaderOrErr.get()); | |||
1533 | Reader->collectFuncsToUse(M); | |||
1534 | ProfileIsValid = (Reader->read() == sampleprof_error::success); | |||
1535 | ||||
1536 | if (!RemappingFilename.empty()) { | |||
1537 | // Apply profile remappings to the loaded profile data if requested. | |||
1538 | // For now, we only support remapping symbols encoded using the Itanium | |||
1539 | // C++ ABI's name mangling scheme. | |||
1540 | ReaderOrErr = SampleProfileReaderItaniumRemapper::create( | |||
1541 | RemappingFilename, Ctx, std::move(Reader)); | |||
1542 | if (std::error_code EC = ReaderOrErr.getError()) { | |||
1543 | std::string Msg = "Could not open profile remapping file: " + EC.message(); | |||
1544 | Ctx.diagnose(DiagnosticInfoSampleProfile(Filename, Msg)); | |||
1545 | return false; | |||
1546 | } | |||
1547 | Reader = std::move(ReaderOrErr.get()); | |||
1548 | ProfileIsValid = (Reader->read() == sampleprof_error::success); | |||
1549 | } | |||
1550 | return true; | |||
1551 | } | |||
1552 | ||||
1553 | ModulePass *llvm::createSampleProfileLoaderPass() { | |||
1554 | return new SampleProfileLoaderLegacyPass(); | |||
1555 | } | |||
1556 | ||||
1557 | ModulePass *llvm::createSampleProfileLoaderPass(StringRef Name) { | |||
1558 | return new SampleProfileLoaderLegacyPass(Name); | |||
1559 | } | |||
1560 | ||||
1561 | bool SampleProfileLoader::runOnModule(Module &M, ModuleAnalysisManager *AM, | |||
1562 | ProfileSummaryInfo *_PSI) { | |||
1563 | FunctionSamples::GUIDToFuncNameMapper Mapper(M); | |||
1564 | if (!ProfileIsValid) | |||
1565 | return false; | |||
1566 | ||||
1567 | PSI = _PSI; | |||
1568 | if (M.getProfileSummary() == nullptr) | |||
1569 | M.setProfileSummary(Reader->getSummary().getMD(M.getContext())); | |||
1570 | ||||
1571 | // Compute the total number of samples collected in this profile. | |||
1572 | for (const auto &I : Reader->getProfiles()) | |||
1573 | TotalCollectedSamples += I.second.getTotalSamples(); | |||
1574 | ||||
1575 | // Populate the symbol map. | |||
1576 | for (const auto &N_F : M.getValueSymbolTable()) { | |||
1577 | StringRef OrigName = N_F.getKey(); | |||
1578 | Function *F = dyn_cast<Function>(N_F.getValue()); | |||
1579 | if (F == nullptr) | |||
1580 | continue; | |||
1581 | SymbolMap[OrigName] = F; | |||
1582 | auto pos = OrigName.find('.'); | |||
1583 | if (pos != StringRef::npos) { | |||
1584 | StringRef NewName = OrigName.substr(0, pos); | |||
1585 | auto r = SymbolMap.insert(std::make_pair(NewName, F)); | |||
1586 | // Failiing to insert means there is already an entry in SymbolMap, | |||
1587 | // thus there are multiple functions that are mapped to the same | |||
1588 | // stripped name. In this case of name conflicting, set the value | |||
1589 | // to nullptr to avoid confusion. | |||
1590 | if (!r.second) | |||
1591 | r.first->second = nullptr; | |||
1592 | } | |||
1593 | } | |||
1594 | ||||
1595 | bool retval = false; | |||
1596 | for (auto &F : M) | |||
1597 | if (!F.isDeclaration()) { | |||
1598 | clearFunctionData(); | |||
1599 | retval |= runOnFunction(F, AM); | |||
1600 | } | |||
1601 | return retval; | |||
1602 | } | |||
1603 | ||||
1604 | bool SampleProfileLoaderLegacyPass::runOnModule(Module &M) { | |||
1605 | ACT = &getAnalysis<AssumptionCacheTracker>(); | |||
1606 | TTIWP = &getAnalysis<TargetTransformInfoWrapperPass>(); | |||
1607 | ProfileSummaryInfo *PSI = | |||
1608 | &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI(); | |||
1609 | return SampleLoader.runOnModule(M, nullptr, PSI); | |||
1610 | } | |||
1611 | ||||
1612 | bool SampleProfileLoader::runOnFunction(Function &F, ModuleAnalysisManager *AM) { | |||
1613 | // By default the entry count is initialized to -1, which will be treated | |||
1614 | // conservatively by getEntryCount as the same as unknown (None). This is | |||
1615 | // to avoid newly added code to be treated as cold. If we have samples | |||
1616 | // this will be overwritten in emitAnnotations. | |||
1617 | // If ProfileSampleAccurate is true or F has profile-sample-accurate | |||
1618 | // attribute, initialize the entry count to 0 so callsites or functions | |||
1619 | // unsampled will be treated as cold. | |||
1620 | uint64_t initialEntryCount = | |||
1621 | (ProfileSampleAccurate || F.hasFnAttribute("profile-sample-accurate")) | |||
1622 | ? 0 | |||
1623 | : -1; | |||
1624 | F.setEntryCount(ProfileCount(initialEntryCount, Function::PCT_Real)); | |||
1625 | std::unique_ptr<OptimizationRemarkEmitter> OwnedORE; | |||
1626 | if (AM) { | |||
1627 | auto &FAM = | |||
1628 | AM->getResult<FunctionAnalysisManagerModuleProxy>(*F.getParent()) | |||
1629 | .getManager(); | |||
1630 | ORE = &FAM.getResult<OptimizationRemarkEmitterAnalysis>(F); | |||
1631 | } else { | |||
1632 | OwnedORE = make_unique<OptimizationRemarkEmitter>(&F); | |||
1633 | ORE = OwnedORE.get(); | |||
1634 | } | |||
1635 | Samples = Reader->getSamplesFor(F); | |||
1636 | if (Samples && !Samples->empty()) | |||
1637 | return emitAnnotations(F); | |||
1638 | return false; | |||
1639 | } | |||
1640 | ||||
1641 | PreservedAnalyses SampleProfileLoaderPass::run(Module &M, | |||
1642 | ModuleAnalysisManager &AM) { | |||
1643 | FunctionAnalysisManager &FAM = | |||
1644 | AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager(); | |||
1645 | ||||
1646 | auto GetAssumptionCache = [&](Function &F) -> AssumptionCache & { | |||
1647 | return FAM.getResult<AssumptionAnalysis>(F); | |||
1648 | }; | |||
1649 | auto GetTTI = [&](Function &F) -> TargetTransformInfo & { | |||
1650 | return FAM.getResult<TargetIRAnalysis>(F); | |||
1651 | }; | |||
1652 | ||||
1653 | SampleProfileLoader SampleLoader( | |||
1654 | ProfileFileName.empty() ? SampleProfileFile : ProfileFileName, | |||
1655 | ProfileRemappingFileName.empty() ? SampleProfileRemappingFile | |||
1656 | : ProfileRemappingFileName, | |||
1657 | IsThinLTOPreLink, GetAssumptionCache, GetTTI); | |||
1658 | ||||
1659 | SampleLoader.doInitialization(M); | |||
1660 | ||||
1661 | ProfileSummaryInfo *PSI = &AM.getResult<ProfileSummaryAnalysis>(M); | |||
1662 | if (!SampleLoader.runOnModule(M, &AM, PSI)) | |||
1663 | return PreservedAnalyses::all(); | |||
1664 | ||||
1665 | return PreservedAnalyses::none(); | |||
1666 | } |