1//===- LegacyPassManagers.h - Legacy Pass Infrastructure --------*- C++ -*-===//
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 declares the LLVM Pass Manager infrastructure.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_IR_LEGACYPASSMANAGERS_H
14#define LLVM_IR_LEGACYPASSMANAGERS_H
15
16#include "llvm/ADT/DenseMap.h"
17#include "llvm/ADT/FoldingSet.h"
18#include "llvm/ADT/SmallPtrSet.h"
19#include "llvm/ADT/SmallVector.h"
20#include "llvm/Pass.h"
21#include <vector>
22
23//===----------------------------------------------------------------------===//
24// Overview:
25// The Pass Manager Infrastructure manages passes. It's responsibilities are:
26//
27// o Manage optimization pass execution order
28// o Make required Analysis information available before pass P is run
29// o Release memory occupied by dead passes
30// o If Analysis information is dirtied by a pass then regenerate Analysis
31// information before it is consumed by another pass.
32//
33// Pass Manager Infrastructure uses multiple pass managers. They are
34// PassManager, FunctionPassManager, MPPassManager, FPPassManager, BBPassManager.
35// This class hierarchy uses multiple inheritance but pass managers do not
36// derive from another pass manager.
37//
38// PassManager and FunctionPassManager are two top-level pass manager that
39// represents the external interface of this entire pass manager infrastucture.
40//
41// Important classes :
42//
43// [o] class PMTopLevelManager;
44//
45// Two top level managers, PassManager and FunctionPassManager, derive from
46// PMTopLevelManager. PMTopLevelManager manages information used by top level
47// managers such as last user info.
48//
49// [o] class PMDataManager;
50//
51// PMDataManager manages information, e.g. list of available analysis info,
52// used by a pass manager to manage execution order of passes. It also provides
53// a place to implement common pass manager APIs. All pass managers derive from
54// PMDataManager.
55//
56// [o] class FunctionPassManager;
57//
58// This is a external interface used to manage FunctionPasses. This
59// interface relies on FunctionPassManagerImpl to do all the tasks.
60//
61// [o] class FunctionPassManagerImpl : public ModulePass, PMDataManager,
62// public PMTopLevelManager;
63//
64// FunctionPassManagerImpl is a top level manager. It manages FPPassManagers
65//
66// [o] class FPPassManager : public ModulePass, public PMDataManager;
67//
68// FPPassManager manages FunctionPasses and BBPassManagers
69//
70// [o] class MPPassManager : public Pass, public PMDataManager;
71//
72// MPPassManager manages ModulePasses and FPPassManagers
73//
74// [o] class PassManager;
75//
76// This is a external interface used by various tools to manages passes. It
77// relies on PassManagerImpl to do all the tasks.
78//
79// [o] class PassManagerImpl : public Pass, public PMDataManager,
80// public PMTopLevelManager
81//
82// PassManagerImpl is a top level pass manager responsible for managing
83// MPPassManagers.
84//===----------------------------------------------------------------------===//
85
86#include "llvm/Support/PrettyStackTrace.h"
87
88namespace llvm {
89template <typename T> class ArrayRef;
90class Module;
91class StringRef;
92class Value;
93class Timer;
94class PMDataManager;
95
96// enums for debugging strings
97enum PassDebuggingString {
98 EXECUTION_MSG, // "Executing Pass '" + PassName
99 MODIFICATION_MSG, // "Made Modification '" + PassName
100 FREEING_MSG, // " Freeing Pass '" + PassName
101 ON_FUNCTION_MSG, // "' on Function '" + FunctionName + "'...\n"
102 ON_MODULE_MSG, // "' on Module '" + ModuleName + "'...\n"
103 ON_REGION_MSG, // "' on Region '" + Msg + "'...\n'"
104 ON_LOOP_MSG, // "' on Loop '" + Msg + "'...\n'"
105 ON_CG_MSG // "' on Call Graph Nodes '" + Msg + "'...\n'"
106};
107
108/// PassManagerPrettyStackEntry - This is used to print informative information
109/// about what pass is running when/if a stack trace is generated.
110class PassManagerPrettyStackEntry : public PrettyStackTraceEntry {
111 Pass *P;
112 Value *V;
113 Module *M;
114
115public:
116 explicit PassManagerPrettyStackEntry(Pass *p)
117 : P(p), V(nullptr), M(nullptr) {} // When P is releaseMemory'd.
118 PassManagerPrettyStackEntry(Pass *p, Value &v)
119 : P(p), V(&v), M(nullptr) {} // When P is run on V
120 PassManagerPrettyStackEntry(Pass *p, Module &m)
121 : P(p), V(nullptr), M(&m) {} // When P is run on M
122
123 /// print - Emit information about this stack frame to OS.
124 void print(raw_ostream &OS) const override;
125};
126
127//===----------------------------------------------------------------------===//
128// PMStack
129//
130/// PMStack - This class implements a stack data structure of PMDataManager
131/// pointers.
132///
133/// Top level pass managers (see PassManager.cpp) maintain active Pass Managers
134/// using PMStack. Each Pass implements assignPassManager() to connect itself
135/// with appropriate manager. assignPassManager() walks PMStack to find
136/// suitable manager.
137class PMStack {
138public:
139 typedef std::vector<PMDataManager *>::const_reverse_iterator iterator;
140 iterator begin() const { return S.rbegin(); }
141 iterator end() const { return S.rend(); }
142
143 void pop();
144 PMDataManager *top() const { return S.back(); }
145 void push(PMDataManager *PM);
146 bool empty() const { return S.empty(); }
147
148 void dump() const;
149
150private:
151 std::vector<PMDataManager *> S;
152};
153
154//===----------------------------------------------------------------------===//
155// PMTopLevelManager
156//
157/// PMTopLevelManager manages LastUser info and collects common APIs used by
158/// top level pass managers.
159class PMTopLevelManager {
160protected:
161 explicit PMTopLevelManager(PMDataManager *PMDM);
162
163 unsigned getNumContainedManagers() const {
164 return (unsigned)PassManagers.size();
165 }
166
167 void initializeAllAnalysisInfo();
168
169private:
170 virtual PMDataManager *getAsPMDataManager() = 0;
171 virtual PassManagerType getTopLevelPassManagerType() = 0;
172
173public:
174 /// Schedule pass P for execution. Make sure that passes required by
175 /// P are run before P is run. Update analysis info maintained by
176 /// the manager. Remove dead passes. This is a recursive function.
177 void schedulePass(Pass *P);
178
179 /// Set pass P as the last user of the given analysis passes.
180 void setLastUser(ArrayRef<Pass*> AnalysisPasses, Pass *P);
181
182 /// Collect passes whose last user is P
183 void collectLastUses(SmallVectorImpl<Pass *> &LastUses, Pass *P);
184
185 /// Find the pass that implements Analysis AID. Search immutable
186 /// passes and all pass managers. If desired pass is not found
187 /// then return NULL.
188 Pass *findAnalysisPass(AnalysisID AID);
189
190 /// Retrieve the PassInfo for an analysis.
191 const PassInfo *findAnalysisPassInfo(AnalysisID AID) const;
192
193 /// Find analysis usage information for the pass P.
194 AnalysisUsage *findAnalysisUsage(Pass *P);
195
196 virtual ~PMTopLevelManager();
197
198 /// Add immutable pass and initialize it.
199 void addImmutablePass(ImmutablePass *P);
200
201 inline SmallVectorImpl<ImmutablePass *>& getImmutablePasses() {
202 return ImmutablePasses;
203 }
204
205 void addPassManager(PMDataManager *Manager) {
206 PassManagers.push_back(Manager);
207 }
208
209 // Add Manager into the list of managers that are not directly
210 // maintained by this top level pass manager
211 inline void addIndirectPassManager(PMDataManager *Manager) {
212 IndirectPassManagers.push_back(Manager);
213 }
214
215 // Print passes managed by this top level manager.
216 void dumpPasses() const;
217 void dumpArguments() const;
218
219 // Active Pass Managers
220 PMStack activeStack;
221
222protected:
223 /// Collection of pass managers
224 SmallVector<PMDataManager *, 8> PassManagers;
225
226private:
227 /// Collection of pass managers that are not directly maintained
228 /// by this pass manager
229 SmallVector<PMDataManager *, 8> IndirectPassManagers;
230
231 // Map to keep track of last user of the analysis pass.
232 // LastUser->second is the last user of Lastuser->first.
233 // This is kept in sync with InversedLastUser.
234 DenseMap<Pass *, Pass *> LastUser;
235
236 // Map to keep track of passes that are last used by a pass.
237 // This is kept in sync with LastUser.
238 DenseMap<Pass *, SmallPtrSet<Pass *, 8> > InversedLastUser;
239
240 /// Immutable passes are managed by top level manager.
241 SmallVector<ImmutablePass *, 16> ImmutablePasses;
242
243 /// Map from ID to immutable passes.
244 SmallDenseMap<AnalysisID, ImmutablePass *, 8> ImmutablePassMap;
245
246
247 /// A wrapper around AnalysisUsage for the purpose of uniqueing. The wrapper
248 /// is used to avoid needing to make AnalysisUsage itself a folding set node.
249 struct AUFoldingSetNode : public FoldingSetNode {
250 AnalysisUsage AU;
251 AUFoldingSetNode(const AnalysisUsage &AU) : AU(AU) {}
252 void Profile(FoldingSetNodeID &ID) const {
253 Profile(ID, AU);
254 }
255 static void Profile(FoldingSetNodeID &ID, const AnalysisUsage &AU) {
256 // TODO: We could consider sorting the dependency arrays within the
257 // AnalysisUsage (since they are conceptually unordered).
258 ID.AddBoolean(AU.getPreservesAll());
259 auto ProfileVec = [&](const SmallVectorImpl<AnalysisID>& Vec) {
260 ID.AddInteger(Vec.size());
261 for(AnalysisID AID : Vec)
262 ID.AddPointer(AID);
263 };
264 ProfileVec(AU.getRequiredSet());
265 ProfileVec(AU.getRequiredTransitiveSet());
266 ProfileVec(AU.getPreservedSet());
267 ProfileVec(AU.getUsedSet());
268 }
269 };
270
271 // Contains all of the unique combinations of AnalysisUsage. This is helpful
272 // when we have multiple instances of the same pass since they'll usually
273 // have the same analysis usage and can share storage.
274 FoldingSet<AUFoldingSetNode> UniqueAnalysisUsages;
275
276 // Allocator used for allocating UAFoldingSetNodes. This handles deletion of
277 // all allocated nodes in one fell swoop.
278 SpecificBumpPtrAllocator<AUFoldingSetNode> AUFoldingSetNodeAllocator;
279
280 // Maps from a pass to it's associated entry in UniqueAnalysisUsages. Does
281 // not own the storage associated with either key or value..
282 DenseMap<Pass *, AnalysisUsage*> AnUsageMap;
283
284 /// Collection of PassInfo objects found via analysis IDs and in this top
285 /// level manager. This is used to memoize queries to the pass registry.
286 /// FIXME: This is an egregious hack because querying the pass registry is
287 /// either slow or racy.
288 mutable DenseMap<AnalysisID, const PassInfo *> AnalysisPassInfos;
289};
290
291//===----------------------------------------------------------------------===//
292// PMDataManager
293
294/// PMDataManager provides the common place to manage the analysis data
295/// used by pass managers.
296class PMDataManager {
297public:
298 explicit PMDataManager() : TPM(nullptr), Depth(0) {
299 initializeAnalysisInfo();
300 }
301
302 virtual ~PMDataManager();
303
304 virtual Pass *getAsPass() = 0;
305
306 /// Augment AvailableAnalysis by adding analysis made available by pass P.
307 void recordAvailableAnalysis(Pass *P);
308
309 /// verifyPreservedAnalysis -- Verify analysis presreved by pass P.
310 void verifyPreservedAnalysis(Pass *P);
311
312 /// Remove Analysis that is not preserved by the pass
313 void removeNotPreservedAnalysis(Pass *P);
314
315 /// Remove dead passes used by P.
316 void removeDeadPasses(Pass *P, StringRef Msg,
317 enum PassDebuggingString);
318
319 /// Remove P.
320 void freePass(Pass *P, StringRef Msg,
321 enum PassDebuggingString);
322
323 /// Add pass P into the PassVector. Update
324 /// AvailableAnalysis appropriately if ProcessAnalysis is true.
325 void add(Pass *P, bool ProcessAnalysis = true);
326
327 /// Add RequiredPass into list of lower level passes required by pass P.
328 /// RequiredPass is run on the fly by Pass Manager when P requests it
329 /// through getAnalysis interface.
330 virtual void addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass);
331
332 virtual std::tuple<Pass *, bool> getOnTheFlyPass(Pass *P, AnalysisID PI,
333 Function &F);
334
335 /// Initialize available analysis information.
336 void initializeAnalysisInfo() {
337 AvailableAnalysis.clear();
338 for (auto &IA : InheritedAnalysis)
339 IA = nullptr;
340 }
341
342 // Return true if P preserves high level analysis used by other
343 // passes that are managed by this manager.
344 bool preserveHigherLevelAnalysis(Pass *P);
345
346 /// Populate UsedPasses with analysis pass that are used or required by pass
347 /// P and are available. Populate ReqPassNotAvailable with analysis pass that
348 /// are required by pass P but are not available.
349 void collectRequiredAndUsedAnalyses(
350 SmallVectorImpl<Pass *> &UsedPasses,
351 SmallVectorImpl<AnalysisID> &ReqPassNotAvailable, Pass *P);
352
353 /// All Required analyses should be available to the pass as it runs! Here
354 /// we fill in the AnalysisImpls member of the pass so that it can
355 /// successfully use the getAnalysis() method to retrieve the
356 /// implementations it needs.
357 void initializeAnalysisImpl(Pass *P);
358
359 /// Find the pass that implements Analysis AID. If desired pass is not found
360 /// then return NULL.
361 Pass *findAnalysisPass(AnalysisID AID, bool Direction);
362
363 // Access toplevel manager
364 PMTopLevelManager *getTopLevelManager() { return TPM; }
365 void setTopLevelManager(PMTopLevelManager *T) { TPM = T; }
366
367 unsigned getDepth() const { return Depth; }
368 void setDepth(unsigned newDepth) { Depth = newDepth; }
369
370 // Print routines used by debug-pass
371 void dumpLastUses(Pass *P, unsigned Offset) const;
372 void dumpPassArguments() const;
373 void dumpPassInfo(Pass *P, enum PassDebuggingString S1,
374 enum PassDebuggingString S2, StringRef Msg);
375 void dumpRequiredSet(const Pass *P) const;
376 void dumpPreservedSet(const Pass *P) const;
377 void dumpUsedSet(const Pass *P) const;
378
379 unsigned getNumContainedPasses() const {
380 return (unsigned)PassVector.size();
381 }
382
383 virtual PassManagerType getPassManagerType() const {
384 assert ( 0 && "Invalid use of getPassManagerType");
385 return PMT_Unknown;
386 }
387
388 DenseMap<AnalysisID, Pass*> *getAvailableAnalysis() {
389 return &AvailableAnalysis;
390 }
391
392 // Collect AvailableAnalysis from all the active Pass Managers.
393 void populateInheritedAnalysis(PMStack &PMS) {
394 unsigned Index = 0;
395 for (PMDataManager *PMDM : PMS)
396 InheritedAnalysis[Index++] = PMDM->getAvailableAnalysis();
397 }
398
399 /// Set the initial size of the module if the user has specified that they
400 /// want remarks for size.
401 /// Returns 0 if the remark was not requested.
402 unsigned initSizeRemarkInfo(
403 Module &M,
404 StringMap<std::pair<unsigned, unsigned>> &FunctionToInstrCount);
405
406 /// Emit a remark signifying that the number of IR instructions in the module
407 /// changed.
408 /// \p F is optionally passed by passes which run on Functions, and thus
409 /// always know whether or not a non-empty function is available.
410 ///
411 /// \p FunctionToInstrCount maps the name of a \p Function to a pair. The
412 /// first member of the pair is the IR count of the \p Function before running
413 /// \p P, and the second member is the IR count of the \p Function after
414 /// running \p P.
415 void emitInstrCountChangedRemark(
416 Pass *P, Module &M, int64_t Delta, unsigned CountBefore,
417 StringMap<std::pair<unsigned, unsigned>> &FunctionToInstrCount,
418 Function *F = nullptr);
419
420protected:
421 // Top level manager.
422 PMTopLevelManager *TPM;
423
424 // Collection of pass that are managed by this manager
425 SmallVector<Pass *, 16> PassVector;
426
427 // Collection of Analysis provided by Parent pass manager and
428 // used by current pass manager. At at time there can not be more
429 // then PMT_Last active pass mangers.
430 DenseMap<AnalysisID, Pass *> *InheritedAnalysis[PMT_Last];
431
432 /// isPassDebuggingExecutionsOrMore - Return true if -debug-pass=Executions
433 /// or higher is specified.
434 bool isPassDebuggingExecutionsOrMore() const;
435
436private:
437 void dumpAnalysisUsage(StringRef Msg, const Pass *P,
438 const AnalysisUsage::VectorType &Set) const;
439
440 // Set of available Analysis. This information is used while scheduling
441 // pass. If a pass requires an analysis which is not available then
442 // the required analysis pass is scheduled to run before the pass itself is
443 // scheduled to run.
444 DenseMap<AnalysisID, Pass*> AvailableAnalysis;
445
446 // Collection of higher level analysis used by the pass managed by
447 // this manager.
448 SmallVector<Pass *, 16> HigherLevelAnalysis;
449
450 unsigned Depth;
451};
452
453//===----------------------------------------------------------------------===//
454// FPPassManager
455//
456/// FPPassManager manages BBPassManagers and FunctionPasses.
457/// It batches all function passes and basic block pass managers together and
458/// sequence them to process one function at a time before processing next
459/// function.
460class FPPassManager : public ModulePass, public PMDataManager {
461public:
462 static char ID;
463 explicit FPPassManager()
464 : ModulePass(ID), PMDataManager() { }
465
466 /// run - Execute all of the passes scheduled for execution. Keep track of
467 /// whether any of the passes modifies the module, and if so, return true.
468 bool runOnFunction(Function &F);
469 bool runOnModule(Module &M) override;
470
471 /// cleanup - After running all passes, clean up pass manager cache.
472 void cleanup();
473
474 /// doInitialization - Overrides ModulePass doInitialization for global
475 /// initialization tasks
476 ///
477 using ModulePass::doInitialization;
478
479 /// doInitialization - Run all of the initializers for the function passes.
480 ///
481 bool doInitialization(Module &M) override;
482
483 /// doFinalization - Overrides ModulePass doFinalization for global
484 /// finalization tasks
485 ///
486 using ModulePass::doFinalization;
487
488 /// doFinalization - Run all of the finalizers for the function passes.
489 ///
490 bool doFinalization(Module &M) override;
491
492 PMDataManager *getAsPMDataManager() override { return this; }
493 Pass *getAsPass() override { return this; }
494
495 /// Pass Manager itself does not invalidate any analysis info.
496 void getAnalysisUsage(AnalysisUsage &Info) const override {
497 Info.setPreservesAll();
498 }
499
500 // Print passes managed by this manager
501 void dumpPassStructure(unsigned Offset) override;
502
503 StringRef getPassName() const override { return "Function Pass Manager"; }
504
505 FunctionPass *getContainedPass(unsigned N) {
506 assert ( N < PassVector.size() && "Pass number out of range!");
507 FunctionPass *FP = static_cast<FunctionPass *>(PassVector[N]);
508 return FP;
509 }
510
511 PassManagerType getPassManagerType() const override {
512 return PMT_FunctionPassManager;
513 }
514};
515
516}
517
518#endif
519