LLVM  6.0.0svn
LegacyPassManagers.h
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1 //===- LegacyPassManagers.h - Legacy Pass Infrastructure --------*- C++ -*-===//
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 declares the LLVM Pass Manager infrastructure.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_IR_LEGACYPASSMANAGERS_H
15 #define LLVM_IR_LEGACYPASSMANAGERS_H
16 
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/FoldingSet.h"
19 #include "llvm/ADT/SmallPtrSet.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/Pass.h"
22 #include <vector>
23 
24 //===----------------------------------------------------------------------===//
25 // Overview:
26 // The Pass Manager Infrastructure manages passes. It's responsibilities are:
27 //
28 // o Manage optimization pass execution order
29 // o Make required Analysis information available before pass P is run
30 // o Release memory occupied by dead passes
31 // o If Analysis information is dirtied by a pass then regenerate Analysis
32 // information before it is consumed by another pass.
33 //
34 // Pass Manager Infrastructure uses multiple pass managers. They are
35 // PassManager, FunctionPassManager, MPPassManager, FPPassManager, BBPassManager.
36 // This class hierarchy uses multiple inheritance but pass managers do not
37 // derive from another pass manager.
38 //
39 // PassManager and FunctionPassManager are two top-level pass manager that
40 // represents the external interface of this entire pass manager infrastucture.
41 //
42 // Important classes :
43 //
44 // [o] class PMTopLevelManager;
45 //
46 // Two top level managers, PassManager and FunctionPassManager, derive from
47 // PMTopLevelManager. PMTopLevelManager manages information used by top level
48 // managers such as last user info.
49 //
50 // [o] class PMDataManager;
51 //
52 // PMDataManager manages information, e.g. list of available analysis info,
53 // used by a pass manager to manage execution order of passes. It also provides
54 // a place to implement common pass manager APIs. All pass managers derive from
55 // PMDataManager.
56 //
57 // [o] class BBPassManager : public FunctionPass, public PMDataManager;
58 //
59 // BBPassManager manages BasicBlockPasses.
60 //
61 // [o] class FunctionPassManager;
62 //
63 // This is a external interface used to manage FunctionPasses. This
64 // interface relies on FunctionPassManagerImpl to do all the tasks.
65 //
66 // [o] class FunctionPassManagerImpl : public ModulePass, PMDataManager,
67 // public PMTopLevelManager;
68 //
69 // FunctionPassManagerImpl is a top level manager. It manages FPPassManagers
70 //
71 // [o] class FPPassManager : public ModulePass, public PMDataManager;
72 //
73 // FPPassManager manages FunctionPasses and BBPassManagers
74 //
75 // [o] class MPPassManager : public Pass, public PMDataManager;
76 //
77 // MPPassManager manages ModulePasses and FPPassManagers
78 //
79 // [o] class PassManager;
80 //
81 // This is a external interface used by various tools to manages passes. It
82 // relies on PassManagerImpl to do all the tasks.
83 //
84 // [o] class PassManagerImpl : public Pass, public PMDataManager,
85 // public PMTopLevelManager
86 //
87 // PassManagerImpl is a top level pass manager responsible for managing
88 // MPPassManagers.
89 //===----------------------------------------------------------------------===//
90 
92 
93 namespace llvm {
94 template <typename T> class ArrayRef;
95 class Module;
96 class Pass;
97 class StringRef;
98 class Value;
99 class Timer;
100 class PMDataManager;
101 
102 // enums for debugging strings
104  EXECUTION_MSG, // "Executing Pass '" + PassName
105  MODIFICATION_MSG, // "Made Modification '" + PassName
106  FREEING_MSG, // " Freeing Pass '" + PassName
107  ON_BASICBLOCK_MSG, // "' on BasicBlock '" + InstructionName + "'...\n"
108  ON_FUNCTION_MSG, // "' on Function '" + FunctionName + "'...\n"
109  ON_MODULE_MSG, // "' on Module '" + ModuleName + "'...\n"
110  ON_REGION_MSG, // "' on Region '" + Msg + "'...\n'"
111  ON_LOOP_MSG, // "' on Loop '" + Msg + "'...\n'"
112  ON_CG_MSG // "' on Call Graph Nodes '" + Msg + "'...\n'"
113 };
114 
115 /// PassManagerPrettyStackEntry - This is used to print informative information
116 /// about what pass is running when/if a stack trace is generated.
118  Pass *P;
119  Value *V;
120  Module *M;
121 
122 public:
124  : P(p), V(nullptr), M(nullptr) {} // When P is releaseMemory'd.
126  : P(p), V(&v), M(nullptr) {} // When P is run on V
128  : P(p), V(nullptr), M(&m) {} // When P is run on M
129 
130  /// print - Emit information about this stack frame to OS.
131  void print(raw_ostream &OS) const override;
132 };
133 
134 //===----------------------------------------------------------------------===//
135 // PMStack
136 //
137 /// PMStack - This class implements a stack data structure of PMDataManager
138 /// pointers.
139 ///
140 /// Top level pass managers (see PassManager.cpp) maintain active Pass Managers
141 /// using PMStack. Each Pass implements assignPassManager() to connect itself
142 /// with appropriate manager. assignPassManager() walks PMStack to find
143 /// suitable manager.
144 class PMStack {
145 public:
146  typedef std::vector<PMDataManager *>::const_reverse_iterator iterator;
147  iterator begin() const { return S.rbegin(); }
148  iterator end() const { return S.rend(); }
149 
150  void pop();
151  PMDataManager *top() const { return S.back(); }
152  void push(PMDataManager *PM);
153  bool empty() const { return S.empty(); }
154 
155  void dump() const;
156 
157 private:
158  std::vector<PMDataManager *> S;
159 };
160 
161 //===----------------------------------------------------------------------===//
162 // PMTopLevelManager
163 //
164 /// PMTopLevelManager manages LastUser info and collects common APIs used by
165 /// top level pass managers.
167 protected:
168  explicit PMTopLevelManager(PMDataManager *PMDM);
169 
170  unsigned getNumContainedManagers() const {
171  return (unsigned)PassManagers.size();
172  }
173 
174  void initializeAllAnalysisInfo();
175 
176 private:
177  virtual PMDataManager *getAsPMDataManager() = 0;
178  virtual PassManagerType getTopLevelPassManagerType() = 0;
179 
180 public:
181  /// Schedule pass P for execution. Make sure that passes required by
182  /// P are run before P is run. Update analysis info maintained by
183  /// the manager. Remove dead passes. This is a recursive function.
184  void schedulePass(Pass *P);
185 
186  /// Set pass P as the last user of the given analysis passes.
187  void setLastUser(ArrayRef<Pass*> AnalysisPasses, Pass *P);
188 
189  /// Collect passes whose last user is P
190  void collectLastUses(SmallVectorImpl<Pass *> &LastUses, Pass *P);
191 
192  /// Find the pass that implements Analysis AID. Search immutable
193  /// passes and all pass managers. If desired pass is not found
194  /// then return NULL.
195  Pass *findAnalysisPass(AnalysisID AID);
196 
197  /// Retrieve the PassInfo for an analysis.
198  const PassInfo *findAnalysisPassInfo(AnalysisID AID) const;
199 
200  /// Find analysis usage information for the pass P.
201  AnalysisUsage *findAnalysisUsage(Pass *P);
202 
203  virtual ~PMTopLevelManager();
204 
205  /// Add immutable pass and initialize it.
206  void addImmutablePass(ImmutablePass *P);
207 
209  return ImmutablePasses;
210  }
211 
212  void addPassManager(PMDataManager *Manager) {
213  PassManagers.push_back(Manager);
214  }
215 
216  // Add Manager into the list of managers that are not directly
217  // maintained by this top level pass manager
218  inline void addIndirectPassManager(PMDataManager *Manager) {
219  IndirectPassManagers.push_back(Manager);
220  }
221 
222  // Print passes managed by this top level manager.
223  void dumpPasses() const;
224  void dumpArguments() const;
225 
226  // Active Pass Managers
228 
229 protected:
230  /// Collection of pass managers
232 
233 private:
234  /// Collection of pass managers that are not directly maintained
235  /// by this pass manager
236  SmallVector<PMDataManager *, 8> IndirectPassManagers;
237 
238  // Map to keep track of last user of the analysis pass.
239  // LastUser->second is the last user of Lastuser->first.
240  DenseMap<Pass *, Pass *> LastUser;
241 
242  // Map to keep track of passes that are last used by a pass.
243  // This inverse map is initialized at PM->run() based on
244  // LastUser map.
245  DenseMap<Pass *, SmallPtrSet<Pass *, 8> > InversedLastUser;
246 
247  /// Immutable passes are managed by top level manager.
248  SmallVector<ImmutablePass *, 16> ImmutablePasses;
249 
250  /// Map from ID to immutable passes.
252 
253 
254  /// A wrapper around AnalysisUsage for the purpose of uniqueing. The wrapper
255  /// is used to avoid needing to make AnalysisUsage itself a folding set node.
256  struct AUFoldingSetNode : public FoldingSetNode {
257  AnalysisUsage AU;
258  AUFoldingSetNode(const AnalysisUsage &AU) : AU(AU) {}
259  void Profile(FoldingSetNodeID &ID) const {
260  Profile(ID, AU);
261  }
262  static void Profile(FoldingSetNodeID &ID, const AnalysisUsage &AU) {
263  // TODO: We could consider sorting the dependency arrays within the
264  // AnalysisUsage (since they are conceptually unordered).
265  ID.AddBoolean(AU.getPreservesAll());
266  auto ProfileVec = [&](const SmallVectorImpl<AnalysisID>& Vec) {
267  ID.AddInteger(Vec.size());
268  for(AnalysisID AID : Vec)
269  ID.AddPointer(AID);
270  };
271  ProfileVec(AU.getRequiredSet());
272  ProfileVec(AU.getRequiredTransitiveSet());
273  ProfileVec(AU.getPreservedSet());
274  ProfileVec(AU.getUsedSet());
275  }
276  };
277 
278  // Contains all of the unique combinations of AnalysisUsage. This is helpful
279  // when we have multiple instances of the same pass since they'll usually
280  // have the same analysis usage and can share storage.
281  FoldingSet<AUFoldingSetNode> UniqueAnalysisUsages;
282 
283  // Allocator used for allocating UAFoldingSetNodes. This handles deletion of
284  // all allocated nodes in one fell swoop.
285  SpecificBumpPtrAllocator<AUFoldingSetNode> AUFoldingSetNodeAllocator;
286 
287  // Maps from a pass to it's associated entry in UniqueAnalysisUsages. Does
288  // not own the storage associated with either key or value..
290 
291  /// Collection of PassInfo objects found via analysis IDs and in this top
292  /// level manager. This is used to memoize queries to the pass registry.
293  /// FIXME: This is an egregious hack because querying the pass registry is
294  /// either slow or racy.
295  mutable DenseMap<AnalysisID, const PassInfo *> AnalysisPassInfos;
296 };
297 
298 //===----------------------------------------------------------------------===//
299 // PMDataManager
300 
301 /// PMDataManager provides the common place to manage the analysis data
302 /// used by pass managers.
304 public:
305  explicit PMDataManager() : TPM(nullptr), Depth(0) {
306  initializeAnalysisInfo();
307  }
308 
309  virtual ~PMDataManager();
310 
311  virtual Pass *getAsPass() = 0;
312 
313  /// Augment AvailableAnalysis by adding analysis made available by pass P.
314  void recordAvailableAnalysis(Pass *P);
315 
316  /// verifyPreservedAnalysis -- Verify analysis presreved by pass P.
317  void verifyPreservedAnalysis(Pass *P);
318 
319  /// Remove Analysis that is not preserved by the pass
320  void removeNotPreservedAnalysis(Pass *P);
321 
322  /// Remove dead passes used by P.
323  void removeDeadPasses(Pass *P, StringRef Msg,
324  enum PassDebuggingString);
325 
326  /// Remove P.
327  void freePass(Pass *P, StringRef Msg,
328  enum PassDebuggingString);
329 
330  /// Add pass P into the PassVector. Update
331  /// AvailableAnalysis appropriately if ProcessAnalysis is true.
332  void add(Pass *P, bool ProcessAnalysis = true);
333 
334  /// Add RequiredPass into list of lower level passes required by pass P.
335  /// RequiredPass is run on the fly by Pass Manager when P requests it
336  /// through getAnalysis interface.
337  virtual void addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass);
338 
339  virtual Pass *getOnTheFlyPass(Pass *P, AnalysisID PI, Function &F);
340 
341  /// Initialize available analysis information.
343  AvailableAnalysis.clear();
344  for (unsigned i = 0; i < PMT_Last; ++i)
345  InheritedAnalysis[i] = nullptr;
346  }
347 
348  // Return true if P preserves high level analysis used by other
349  // passes that are managed by this manager.
350  bool preserveHigherLevelAnalysis(Pass *P);
351 
352  /// Populate UsedPasses with analysis pass that are used or required by pass
353  /// P and are available. Populate ReqPassNotAvailable with analysis pass that
354  /// are required by pass P but are not available.
355  void collectRequiredAndUsedAnalyses(
356  SmallVectorImpl<Pass *> &UsedPasses,
357  SmallVectorImpl<AnalysisID> &ReqPassNotAvailable, Pass *P);
358 
359  /// All Required analyses should be available to the pass as it runs! Here
360  /// we fill in the AnalysisImpls member of the pass so that it can
361  /// successfully use the getAnalysis() method to retrieve the
362  /// implementations it needs.
363  void initializeAnalysisImpl(Pass *P);
364 
365  /// Find the pass that implements Analysis AID. If desired pass is not found
366  /// then return NULL.
367  Pass *findAnalysisPass(AnalysisID AID, bool Direction);
368 
369  // Access toplevel manager
372 
373  unsigned getDepth() const { return Depth; }
374  void setDepth(unsigned newDepth) { Depth = newDepth; }
375 
376  // Print routines used by debug-pass
377  void dumpLastUses(Pass *P, unsigned Offset) const;
378  void dumpPassArguments() const;
379  void dumpPassInfo(Pass *P, enum PassDebuggingString S1,
380  enum PassDebuggingString S2, StringRef Msg);
381  void dumpRequiredSet(const Pass *P) const;
382  void dumpPreservedSet(const Pass *P) const;
383  void dumpUsedSet(const Pass *P) const;
384 
385  unsigned getNumContainedPasses() const {
386  return (unsigned)PassVector.size();
387  }
388 
390  assert ( 0 && "Invalid use of getPassManagerType");
391  return PMT_Unknown;
392  }
393 
395  return &AvailableAnalysis;
396  }
397 
398  // Collect AvailableAnalysis from all the active Pass Managers.
400  unsigned Index = 0;
401  for (PMStack::iterator I = PMS.begin(), E = PMS.end();
402  I != E; ++I)
403  InheritedAnalysis[Index++] = (*I)->getAvailableAnalysis();
404  }
405 
406 protected:
407  // Top level manager.
409 
410  // Collection of pass that are managed by this manager
412 
413  // Collection of Analysis provided by Parent pass manager and
414  // used by current pass manager. At at time there can not be more
415  // then PMT_Last active pass mangers.
417 
418  /// isPassDebuggingExecutionsOrMore - Return true if -debug-pass=Executions
419  /// or higher is specified.
420  bool isPassDebuggingExecutionsOrMore() const;
421 
422 private:
423  void dumpAnalysisUsage(StringRef Msg, const Pass *P,
424  const AnalysisUsage::VectorType &Set) const;
425 
426  // Set of available Analysis. This information is used while scheduling
427  // pass. If a pass requires an analysis which is not available then
428  // the required analysis pass is scheduled to run before the pass itself is
429  // scheduled to run.
430  DenseMap<AnalysisID, Pass*> AvailableAnalysis;
431 
432  // Collection of higher level analysis used by the pass managed by
433  // this manager.
434  SmallVector<Pass *, 16> HigherLevelAnalysis;
435 
436  unsigned Depth;
437 };
438 
439 //===----------------------------------------------------------------------===//
440 // FPPassManager
441 //
442 /// FPPassManager manages BBPassManagers and FunctionPasses.
443 /// It batches all function passes and basic block pass managers together and
444 /// sequence them to process one function at a time before processing next
445 /// function.
446 class FPPassManager : public ModulePass, public PMDataManager {
447 public:
448  static char ID;
449  explicit FPPassManager()
450  : ModulePass(ID), PMDataManager() { }
451 
452  /// run - Execute all of the passes scheduled for execution. Keep track of
453  /// whether any of the passes modifies the module, and if so, return true.
454  bool runOnFunction(Function &F);
455  bool runOnModule(Module &M) override;
456 
457  /// cleanup - After running all passes, clean up pass manager cache.
458  void cleanup();
459 
460  /// doInitialization - Overrides ModulePass doInitialization for global
461  /// initialization tasks
462  ///
464 
465  /// doInitialization - Run all of the initializers for the function passes.
466  ///
467  bool doInitialization(Module &M) override;
468 
469  /// doFinalization - Overrides ModulePass doFinalization for global
470  /// finalization tasks
471  ///
473 
474  /// doFinalization - Run all of the finalizers for the function passes.
475  ///
476  bool doFinalization(Module &M) override;
477 
478  PMDataManager *getAsPMDataManager() override { return this; }
479  Pass *getAsPass() override { return this; }
480 
481  /// Pass Manager itself does not invalidate any analysis info.
482  void getAnalysisUsage(AnalysisUsage &Info) const override {
483  Info.setPreservesAll();
484  }
485 
486  // Print passes managed by this manager
487  void dumpPassStructure(unsigned Offset) override;
488 
489  StringRef getPassName() const override { return "Function Pass Manager"; }
490 
492  assert ( N < PassVector.size() && "Pass number out of range!");
493  FunctionPass *FP = static_cast<FunctionPass *>(PassVector[N]);
494  return FP;
495  }
496 
499  }
500 };
501 
503 }
504 
505 #endif
PMTopLevelManager * TPM
Pass interface - Implemented by all &#39;passes&#39;.
Definition: Pass.h:81
void AddPointer(const void *Ptr)
Add* - Add various data types to Bit data.
Definition: FoldingSet.cpp:52
StringRef getPassName() const override
getPassName - Return a nice clean name for a pass.
PassManagerType
Different types of internal pass managers.
Definition: Pass.h:54
PassManagerPrettyStackEntry(Pass *p, Value &v)
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:63
std::vector< PMDataManager * >::const_reverse_iterator iterator
F(f)
PMDataManager * getAsPMDataManager() override
const VectorType & getUsedSet() const
static void cleanup(BlockFrequencyInfoImplBase &BFI)
Clear all memory not needed downstream.
const VectorType & getRequiredSet() const
PMTopLevelManager manages LastUser info and collects common APIs used by top level pass managers...
Timer * getPassTimer(Pass *)
If TimingInfo is enabled then start pass timer.
void setDepth(unsigned newDepth)
void addPassManager(PMDataManager *Manager)
iterator begin() const
virtual bool doFinalization(Module &)
doFinalization - Virtual method overriden by subclasses to do any necessary clean up after all passes...
Definition: Pass.h:110
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:42
void initializeAnalysisInfo()
Initialize available analysis information.
void AddInteger(signed I)
Definition: FoldingSet.cpp:61
const VectorType & getPreservedSet() const
void populateInheritedAnalysis(PMStack &PMS)
iterator end() const
FPPassManager manages BBPassManagers and FunctionPasses.
PMStack - This class implements a stack data structure of PMDataManager pointers. ...
PassManagerPrettyStackEntry - This is used to print informative information about what pass is runnin...
PassManagerPrettyStackEntry(Pass *p, Module &m)
This class is used to track the amount of time spent between invocations of its startTimer()/stopTime...
Definition: Timer.h:76
#define T
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
unsigned getNumContainedManagers() const
virtual bool doInitialization(Module &)
doInitialization - Virtual method overridden by subclasses to do any necessary initialization before ...
Definition: Pass.h:106
FoldingSetNodeID - This class is used to gather all the unique data bits of a node.
Definition: FoldingSet.h:306
static bool runOnFunction(Function &F, bool PostInlining)
#define P(N)
void dump(const SparseBitVector< ElementSize > &LHS, raw_ostream &out)
void print(raw_ostream &OS) const override
print - Emit information about this stack frame to OS.
void addIndirectPassManager(PMDataManager *Manager)
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
virtual PassManagerType getPassManagerType() const
void AddBoolean(bool B)
Definition: FoldingSet.h:325
Represent the analysis usage information of a pass.
FunctionPass class - This class is used to implement most global optimizations.
Definition: Pass.h:285
SmallVectorImpl< ImmutablePass * > & getImmutablePasses()
PassInfo class - An instance of this class exists for every pass known by the system, and can be obtained from a live Pass by calling its getPassInfo() method.
Definition: PassInfo.h:31
PrettyStackTraceEntry - This class is used to represent a frame of the "pretty" stack trace that is d...
print lazy value Lazy Value Info Printer Pass
ImmutablePass class - This class is used to provide information that does not need to be run...
Definition: Pass.h:256
FPPassManager.
Definition: Pass.h:58
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:864
SmallVector< Pass *, 16 > PassVector
const void * AnalysisID
Definition: Pass.h:49
Pass * getAsPass() override
void getAnalysisUsage(AnalysisUsage &Info) const override
Pass Manager itself does not invalidate any analysis info.
DenseMap< AnalysisID, Pass * > * getAvailableAnalysis()
void setPreservesAll()
Set by analyses that do not transform their input at all.
const VectorType & getRequiredTransitiveSet() const
void setTopLevelManager(PMTopLevelManager *T)
SmallVector< PMDataManager *, 8 > PassManagers
Collection of pass managers.
Node - This class is used to maintain the singly linked bucket list in a folding set.
Definition: FoldingSet.h:136
FunctionPass * getContainedPass(unsigned N)
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
ModulePass class - This class is used to implement unstructured interprocedural optimizations and ana...
Definition: Pass.h:225
PMDataManager provides the common place to manage the analysis data used by pass managers.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
PMDataManager * top() const
LLVM Value Representation.
Definition: Value.h:73
unsigned getNumContainedPasses() const
bool empty() const
PMTopLevelManager * getTopLevelManager()
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:44
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
unsigned getDepth() const
bool getPreservesAll() const
Determine whether a pass said it does not transform its input at all.
PassManagerType getPassManagerType() const override