LLVM 17.0.0git
SparsePropagation.h
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1//===- SparsePropagation.h - Sparse Conditional Property Propagation ------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements an abstract sparse conditional propagation algorithm,
10// modeled after SCCP, but with a customizable lattice function.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_ANALYSIS_SPARSEPROPAGATION_H
15#define LLVM_ANALYSIS_SPARSEPROPAGATION_H
16
18#include "llvm/IR/Constants.h"
20#include "llvm/Support/Debug.h"
21#include <set>
22
23#define DEBUG_TYPE "sparseprop"
24
25namespace llvm {
26
27/// A template for translating between LLVM Values and LatticeKeys. Clients must
28/// provide a specialization of LatticeKeyInfo for their LatticeKey type.
29template <class LatticeKey> struct LatticeKeyInfo {
30 // static inline Value *getValueFromLatticeKey(LatticeKey Key);
31 // static inline LatticeKey getLatticeKeyFromValue(Value *V);
32};
33
34template <class LatticeKey, class LatticeVal,
35 class KeyInfo = LatticeKeyInfo<LatticeKey>>
36class SparseSolver;
37
38/// AbstractLatticeFunction - This class is implemented by the dataflow instance
39/// to specify what the lattice values are and how they handle merges etc. This
40/// gives the client the power to compute lattice values from instructions,
41/// constants, etc. The current requirement is that lattice values must be
42/// copyable. At the moment, nothing tries to avoid copying. Additionally,
43/// lattice keys must be able to be used as keys of a mapping data structure.
44/// Internally, the generic solver currently uses a DenseMap to map lattice keys
45/// to lattice values. If the lattice key is a non-standard type, a
46/// specialization of DenseMapInfo must be provided.
47template <class LatticeKey, class LatticeVal> class AbstractLatticeFunction {
48private:
49 LatticeVal UndefVal, OverdefinedVal, UntrackedVal;
50
51public:
52 AbstractLatticeFunction(LatticeVal undefVal, LatticeVal overdefinedVal,
53 LatticeVal untrackedVal) {
54 UndefVal = undefVal;
55 OverdefinedVal = overdefinedVal;
56 UntrackedVal = untrackedVal;
57 }
58
59 virtual ~AbstractLatticeFunction() = default;
60
61 LatticeVal getUndefVal() const { return UndefVal; }
62 LatticeVal getOverdefinedVal() const { return OverdefinedVal; }
63 LatticeVal getUntrackedVal() const { return UntrackedVal; }
64
65 /// IsUntrackedValue - If the specified LatticeKey is obviously uninteresting
66 /// to the analysis (i.e., it would always return UntrackedVal), this
67 /// function can return true to avoid pointless work.
68 virtual bool IsUntrackedValue(LatticeKey Key) { return false; }
69
70 /// ComputeLatticeVal - Compute and return a LatticeVal corresponding to the
71 /// given LatticeKey.
72 virtual LatticeVal ComputeLatticeVal(LatticeKey Key) {
73 return getOverdefinedVal();
74 }
75
76 /// IsSpecialCasedPHI - Given a PHI node, determine whether this PHI node is
77 /// one that the we want to handle through ComputeInstructionState.
78 virtual bool IsSpecialCasedPHI(PHINode *PN) { return false; }
79
80 /// MergeValues - Compute and return the merge of the two specified lattice
81 /// values. Merging should only move one direction down the lattice to
82 /// guarantee convergence (toward overdefined).
83 virtual LatticeVal MergeValues(LatticeVal X, LatticeVal Y) {
84 return getOverdefinedVal(); // always safe, never useful.
85 }
86
87 /// ComputeInstructionState - Compute the LatticeKeys that change as a result
88 /// of executing instruction \p I. Their associated LatticeVals are store in
89 /// \p ChangedValues.
90 virtual void
94
95 /// PrintLatticeVal - Render the given LatticeVal to the specified stream.
96 virtual void PrintLatticeVal(LatticeVal LV, raw_ostream &OS);
97
98 /// PrintLatticeKey - Render the given LatticeKey to the specified stream.
99 virtual void PrintLatticeKey(LatticeKey Key, raw_ostream &OS);
100
101 /// GetValueFromLatticeVal - If the given LatticeVal is representable as an
102 /// LLVM value, return it; otherwise, return nullptr. If a type is given, the
103 /// returned value must have the same type. This function is used by the
104 /// generic solver in attempting to resolve branch and switch conditions.
105 virtual Value *GetValueFromLatticeVal(LatticeVal LV, Type *Ty = nullptr) {
106 return nullptr;
107 }
108};
109
110/// SparseSolver - This class is a general purpose solver for Sparse Conditional
111/// Propagation with a programmable lattice function.
112template <class LatticeKey, class LatticeVal, class KeyInfo>
114
115 /// LatticeFunc - This is the object that knows the lattice and how to
116 /// compute transfer functions.
118
119 /// ValueState - Holds the LatticeVals associated with LatticeKeys.
121
122 /// BBExecutable - Holds the basic blocks that are executable.
124
125 /// ValueWorkList - Holds values that should be processed.
126 SmallVector<Value *, 64> ValueWorkList;
127
128 /// BBWorkList - Holds basic blocks that should be processed.
130
131 using Edge = std::pair<BasicBlock *, BasicBlock *>;
132
133 /// KnownFeasibleEdges - Entries in this set are edges which have already had
134 /// PHI nodes retriggered.
135 std::set<Edge> KnownFeasibleEdges;
136
137public:
138 explicit SparseSolver(
140 : LatticeFunc(Lattice) {}
141 SparseSolver(const SparseSolver &) = delete;
143
144 /// Solve - Solve for constants and executable blocks.
145 void Solve();
146
147 void Print(raw_ostream &OS) const;
148
149 /// getExistingValueState - Return the LatticeVal object corresponding to the
150 /// given value from the ValueState map. If the value is not in the map,
151 /// UntrackedVal is returned, unlike the getValueState method.
152 LatticeVal getExistingValueState(LatticeKey Key) const {
153 auto I = ValueState.find(Key);
154 return I != ValueState.end() ? I->second : LatticeFunc->getUntrackedVal();
155 }
156
157 /// getValueState - Return the LatticeVal object corresponding to the given
158 /// value from the ValueState map. If the value is not in the map, its state
159 /// is initialized.
160 LatticeVal getValueState(LatticeKey Key);
161
162 /// isEdgeFeasible - Return true if the control flow edge from the 'From'
163 /// basic block to the 'To' basic block is currently feasible. If
164 /// AggressiveUndef is true, then this treats values with unknown lattice
165 /// values as undefined. This is generally only useful when solving the
166 /// lattice, not when querying it.
168 bool AggressiveUndef = false);
169
170 /// isBlockExecutable - Return true if there are any known feasible
171 /// edges into the basic block. This is generally only useful when
172 /// querying the lattice.
174 return BBExecutable.count(BB);
175 }
176
177 /// MarkBlockExecutable - This method can be used by clients to mark all of
178 /// the blocks that are known to be intrinsically live in the processed unit.
180
181private:
182 /// UpdateState - When the state of some LatticeKey is potentially updated to
183 /// the given LatticeVal, this function notices and adds the LLVM value
184 /// corresponding the key to the work list, if needed.
185 void UpdateState(LatticeKey Key, LatticeVal LV);
186
187 /// markEdgeExecutable - Mark a basic block as executable, adding it to the BB
188 /// work list if it is not already executable.
189 void markEdgeExecutable(BasicBlock *Source, BasicBlock *Dest);
190
191 /// getFeasibleSuccessors - Return a vector of booleans to indicate which
192 /// successors are reachable from a given terminator instruction.
193 void getFeasibleSuccessors(Instruction &TI, SmallVectorImpl<bool> &Succs,
194 bool AggressiveUndef);
195
196 void visitInst(Instruction &I);
197 void visitPHINode(PHINode &I);
198 void visitTerminator(Instruction &TI);
199};
200
201//===----------------------------------------------------------------------===//
202// AbstractLatticeFunction Implementation
203//===----------------------------------------------------------------------===//
204
205template <class LatticeKey, class LatticeVal>
207 LatticeVal V, raw_ostream &OS) {
208 if (V == UndefVal)
209 OS << "undefined";
210 else if (V == OverdefinedVal)
211 OS << "overdefined";
212 else if (V == UntrackedVal)
213 OS << "untracked";
214 else
215 OS << "unknown lattice value";
216}
217
218template <class LatticeKey, class LatticeVal>
220 LatticeKey Key, raw_ostream &OS) {
221 OS << "unknown lattice key";
222}
223
224//===----------------------------------------------------------------------===//
225// SparseSolver Implementation
226//===----------------------------------------------------------------------===//
227
228template <class LatticeKey, class LatticeVal, class KeyInfo>
229LatticeVal
231 auto I = ValueState.find(Key);
232 if (I != ValueState.end())
233 return I->second; // Common case, in the map
234
235 if (LatticeFunc->IsUntrackedValue(Key))
236 return LatticeFunc->getUntrackedVal();
237 LatticeVal LV = LatticeFunc->ComputeLatticeVal(Key);
238
239 // If this value is untracked, don't add it to the map.
240 if (LV == LatticeFunc->getUntrackedVal())
241 return LV;
242 return ValueState[Key] = std::move(LV);
243}
244
245template <class LatticeKey, class LatticeVal, class KeyInfo>
247 LatticeVal LV) {
248 auto I = ValueState.find(Key);
249 if (I != ValueState.end() && I->second == LV)
250 return; // No change.
251
252 // Update the state of the given LatticeKey and add its corresponding LLVM
253 // value to the work list.
254 ValueState[Key] = std::move(LV);
255 if (Value *V = KeyInfo::getValueFromLatticeKey(Key))
256 ValueWorkList.push_back(V);
257}
258
259template <class LatticeKey, class LatticeVal, class KeyInfo>
261 BasicBlock *BB) {
262 if (!BBExecutable.insert(BB).second)
263 return;
264 LLVM_DEBUG(dbgs() << "Marking Block Executable: " << BB->getName() << "\n");
265 BBWorkList.push_back(BB); // Add the block to the work list!
266}
267
268template <class LatticeKey, class LatticeVal, class KeyInfo>
270 BasicBlock *Source, BasicBlock *Dest) {
271 if (!KnownFeasibleEdges.insert(Edge(Source, Dest)).second)
272 return; // This edge is already known to be executable!
273
274 LLVM_DEBUG(dbgs() << "Marking Edge Executable: " << Source->getName()
275 << " -> " << Dest->getName() << "\n");
276
277 if (BBExecutable.count(Dest)) {
278 // The destination is already executable, but we just made an edge
279 // feasible that wasn't before. Revisit the PHI nodes in the block
280 // because they have potentially new operands.
281 for (BasicBlock::iterator I = Dest->begin(); isa<PHINode>(I); ++I)
282 visitPHINode(*cast<PHINode>(I));
283 } else {
284 MarkBlockExecutable(Dest);
285 }
286}
287
288template <class LatticeKey, class LatticeVal, class KeyInfo>
289void SparseSolver<LatticeKey, LatticeVal, KeyInfo>::getFeasibleSuccessors(
290 Instruction &TI, SmallVectorImpl<bool> &Succs, bool AggressiveUndef) {
291 Succs.resize(TI.getNumSuccessors());
292 if (TI.getNumSuccessors() == 0)
293 return;
294
295 if (BranchInst *BI = dyn_cast<BranchInst>(&TI)) {
296 if (BI->isUnconditional()) {
297 Succs[0] = true;
298 return;
299 }
300
301 LatticeVal BCValue;
302 if (AggressiveUndef)
303 BCValue =
304 getValueState(KeyInfo::getLatticeKeyFromValue(BI->getCondition()));
305 else
306 BCValue = getExistingValueState(
307 KeyInfo::getLatticeKeyFromValue(BI->getCondition()));
308
309 if (BCValue == LatticeFunc->getOverdefinedVal() ||
310 BCValue == LatticeFunc->getUntrackedVal()) {
311 // Overdefined condition variables can branch either way.
312 Succs[0] = Succs[1] = true;
313 return;
314 }
315
316 // If undefined, neither is feasible yet.
317 if (BCValue == LatticeFunc->getUndefVal())
318 return;
319
320 Constant *C =
321 dyn_cast_or_null<Constant>(LatticeFunc->GetValueFromLatticeVal(
322 std::move(BCValue), BI->getCondition()->getType()));
323 if (!C || !isa<ConstantInt>(C)) {
324 // Non-constant values can go either way.
325 Succs[0] = Succs[1] = true;
326 return;
327 }
328
329 // Constant condition variables mean the branch can only go a single way
330 Succs[C->isNullValue()] = true;
331 return;
332 }
333
334 if (!isa<SwitchInst>(TI)) {
335 // Unknown termintor, assume all successors are feasible.
336 Succs.assign(Succs.size(), true);
337 return;
338 }
339
340 SwitchInst &SI = cast<SwitchInst>(TI);
341 LatticeVal SCValue;
342 if (AggressiveUndef)
343 SCValue = getValueState(KeyInfo::getLatticeKeyFromValue(SI.getCondition()));
344 else
345 SCValue = getExistingValueState(
346 KeyInfo::getLatticeKeyFromValue(SI.getCondition()));
347
348 if (SCValue == LatticeFunc->getOverdefinedVal() ||
349 SCValue == LatticeFunc->getUntrackedVal()) {
350 // All destinations are executable!
351 Succs.assign(TI.getNumSuccessors(), true);
352 return;
353 }
354
355 // If undefined, neither is feasible yet.
356 if (SCValue == LatticeFunc->getUndefVal())
357 return;
358
359 Constant *C = dyn_cast_or_null<Constant>(LatticeFunc->GetValueFromLatticeVal(
360 std::move(SCValue), SI.getCondition()->getType()));
361 if (!C || !isa<ConstantInt>(C)) {
362 // All destinations are executable!
363 Succs.assign(TI.getNumSuccessors(), true);
364 return;
365 }
366 SwitchInst::CaseHandle Case = *SI.findCaseValue(cast<ConstantInt>(C));
367 Succs[Case.getSuccessorIndex()] = true;
368}
369
370template <class LatticeKey, class LatticeVal, class KeyInfo>
372 BasicBlock *From, BasicBlock *To, bool AggressiveUndef) {
373 SmallVector<bool, 16> SuccFeasible;
374 Instruction *TI = From->getTerminator();
375 getFeasibleSuccessors(*TI, SuccFeasible, AggressiveUndef);
376
377 for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
378 if (TI->getSuccessor(i) == To && SuccFeasible[i])
379 return true;
380
381 return false;
382}
383
384template <class LatticeKey, class LatticeVal, class KeyInfo>
386 Instruction &TI) {
387 SmallVector<bool, 16> SuccFeasible;
388 getFeasibleSuccessors(TI, SuccFeasible, true);
389
390 BasicBlock *BB = TI.getParent();
391
392 // Mark all feasible successors executable...
393 for (unsigned i = 0, e = SuccFeasible.size(); i != e; ++i)
394 if (SuccFeasible[i])
395 markEdgeExecutable(BB, TI.getSuccessor(i));
396}
397
398template <class LatticeKey, class LatticeVal, class KeyInfo>
399void SparseSolver<LatticeKey, LatticeVal, KeyInfo>::visitPHINode(PHINode &PN) {
400 // The lattice function may store more information on a PHINode than could be
401 // computed from its incoming values. For example, SSI form stores its sigma
402 // functions as PHINodes with a single incoming value.
403 if (LatticeFunc->IsSpecialCasedPHI(&PN)) {
404 DenseMap<LatticeKey, LatticeVal> ChangedValues;
405 LatticeFunc->ComputeInstructionState(PN, ChangedValues, *this);
406 for (auto &ChangedValue : ChangedValues)
407 if (ChangedValue.second != LatticeFunc->getUntrackedVal())
408 UpdateState(std::move(ChangedValue.first),
409 std::move(ChangedValue.second));
410 return;
411 }
412
413 LatticeKey Key = KeyInfo::getLatticeKeyFromValue(&PN);
414 LatticeVal PNIV = getValueState(Key);
415 LatticeVal Overdefined = LatticeFunc->getOverdefinedVal();
416
417 // If this value is already overdefined (common) just return.
418 if (PNIV == Overdefined || PNIV == LatticeFunc->getUntrackedVal())
419 return; // Quick exit
420
421 // Super-extra-high-degree PHI nodes are unlikely to ever be interesting,
422 // and slow us down a lot. Just mark them overdefined.
423 if (PN.getNumIncomingValues() > 64) {
424 UpdateState(Key, Overdefined);
425 return;
426 }
427
428 // Look at all of the executable operands of the PHI node. If any of them
429 // are overdefined, the PHI becomes overdefined as well. Otherwise, ask the
430 // transfer function to give us the merge of the incoming values.
431 for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
432 // If the edge is not yet known to be feasible, it doesn't impact the PHI.
433 if (!isEdgeFeasible(PN.getIncomingBlock(i), PN.getParent(), true))
434 continue;
435
436 // Merge in this value.
437 LatticeVal OpVal =
438 getValueState(KeyInfo::getLatticeKeyFromValue(PN.getIncomingValue(i)));
439 if (OpVal != PNIV)
440 PNIV = LatticeFunc->MergeValues(PNIV, OpVal);
441
442 if (PNIV == Overdefined)
443 break; // Rest of input values don't matter.
444 }
445
446 // Update the PHI with the compute value, which is the merge of the inputs.
447 UpdateState(Key, PNIV);
448}
449
450template <class LatticeKey, class LatticeVal, class KeyInfo>
451void SparseSolver<LatticeKey, LatticeVal, KeyInfo>::visitInst(Instruction &I) {
452 // PHIs are handled by the propagation logic, they are never passed into the
453 // transfer functions.
454 if (PHINode *PN = dyn_cast<PHINode>(&I))
455 return visitPHINode(*PN);
456
457 // Otherwise, ask the transfer function what the result is. If this is
458 // something that we care about, remember it.
459 DenseMap<LatticeKey, LatticeVal> ChangedValues;
460 LatticeFunc->ComputeInstructionState(I, ChangedValues, *this);
461 for (auto &ChangedValue : ChangedValues)
462 if (ChangedValue.second != LatticeFunc->getUntrackedVal())
463 UpdateState(ChangedValue.first, ChangedValue.second);
464
465 if (I.isTerminator())
466 visitTerminator(I);
467}
468
469template <class LatticeKey, class LatticeVal, class KeyInfo>
471 // Process the work lists until they are empty!
472 while (!BBWorkList.empty() || !ValueWorkList.empty()) {
473 // Process the value work list.
474 while (!ValueWorkList.empty()) {
475 Value *V = ValueWorkList.pop_back_val();
476
477 LLVM_DEBUG(dbgs() << "\nPopped off V-WL: " << *V << "\n");
478
479 // "V" got into the work list because it made a transition. See if any
480 // users are both live and in need of updating.
481 for (User *U : V->users())
482 if (Instruction *Inst = dyn_cast<Instruction>(U))
483 if (BBExecutable.count(Inst->getParent())) // Inst is executable?
484 visitInst(*Inst);
485 }
486
487 // Process the basic block work list.
488 while (!BBWorkList.empty()) {
489 BasicBlock *BB = BBWorkList.pop_back_val();
490
491 LLVM_DEBUG(dbgs() << "\nPopped off BBWL: " << *BB);
492
493 // Notify all instructions in this basic block that they are newly
494 // executable.
495 for (Instruction &I : *BB)
496 visitInst(I);
497 }
498 }
499}
500
501template <class LatticeKey, class LatticeVal, class KeyInfo>
503 raw_ostream &OS) const {
504 if (ValueState.empty())
505 return;
506
507 LatticeKey Key;
508 LatticeVal LV;
509
510 OS << "ValueState:\n";
511 for (auto &Entry : ValueState) {
512 std::tie(Key, LV) = Entry;
513 if (LV == LatticeFunc->getUntrackedVal())
514 continue;
515 OS << "\t";
516 LatticeFunc->PrintLatticeVal(LV, OS);
517 OS << ": ";
518 LatticeFunc->PrintLatticeKey(Key, OS);
519 OS << "\n";
520 }
521}
522} // end namespace llvm
523
524#undef DEBUG_TYPE
525
526#endif // LLVM_ANALYSIS_SPARSEPROPAGATION_H
BlockVerifier::State From
This file contains the declarations for the subclasses of Constant, which represent the different fla...
#define LLVM_DEBUG(X)
Definition: Debug.h:101
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
#define I(x, y, z)
Definition: MD5.cpp:58
static GCMetadataPrinterRegistry::Add< OcamlGCMetadataPrinter > Y("ocaml", "ocaml 3.10-compatible collector")
@ SI
This file defines the SmallPtrSet class.
AbstractLatticeFunction - This class is implemented by the dataflow instance to specify what the latt...
LatticeVal getOverdefinedVal() const
AbstractLatticeFunction(LatticeVal undefVal, LatticeVal overdefinedVal, LatticeVal untrackedVal)
virtual void ComputeInstructionState(Instruction &I, DenseMap< LatticeKey, LatticeVal > &ChangedValues, SparseSolver< LatticeKey, LatticeVal > &SS)=0
ComputeInstructionState - Compute the LatticeKeys that change as a result of executing instruction I.
virtual void PrintLatticeKey(LatticeKey Key, raw_ostream &OS)
PrintLatticeKey - Render the given LatticeKey to the specified stream.
virtual Value * GetValueFromLatticeVal(LatticeVal LV, Type *Ty=nullptr)
GetValueFromLatticeVal - If the given LatticeVal is representable as an LLVM value,...
virtual bool IsUntrackedValue(LatticeKey Key)
IsUntrackedValue - If the specified LatticeKey is obviously uninteresting to the analysis (i....
virtual void PrintLatticeVal(LatticeVal LV, raw_ostream &OS)
PrintLatticeVal - Render the given LatticeVal to the specified stream.
LatticeVal getUntrackedVal() const
virtual LatticeVal MergeValues(LatticeVal X, LatticeVal Y)
MergeValues - Compute and return the merge of the two specified lattice values.
virtual LatticeVal ComputeLatticeVal(LatticeKey Key)
ComputeLatticeVal - Compute and return a LatticeVal corresponding to the given LatticeKey.
virtual ~AbstractLatticeFunction()=default
virtual bool IsSpecialCasedPHI(PHINode *PN)
IsSpecialCasedPHI - Given a PHI node, determine whether this PHI node is one that the we want to hand...
LLVM Basic Block Representation.
Definition: BasicBlock.h:56
iterator begin()
Instruction iterator methods.
Definition: BasicBlock.h:314
InstListType::iterator iterator
Instruction iterators...
Definition: BasicBlock.h:87
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:150
iterator end()
Definition: DenseMap.h:84
unsigned getNumSuccessors() const LLVM_READONLY
Return the number of successors that this instruction has.
const BasicBlock * getParent() const
Definition: Instruction.h:90
BasicBlock * getSuccessor(unsigned Idx) const LLVM_READONLY
Return the specified successor. This instruction must be a terminator.
size_type count(ConstPtrType Ptr) const
count - Return 1 if the specified pointer is in the set, 0 otherwise.
Definition: SmallPtrSet.h:383
SmallPtrSet - This class implements a set which is optimized for holding SmallSize or less elements.
Definition: SmallPtrSet.h:450
size_t size() const
Definition: SmallVector.h:91
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: SmallVector.h:577
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1200
SparseSolver - This class is a general purpose solver for Sparse Conditional Propagation with a progr...
bool isEdgeFeasible(BasicBlock *From, BasicBlock *To, bool AggressiveUndef=false)
isEdgeFeasible - Return true if the control flow edge from the 'From' basic block to the 'To' basic b...
void Print(raw_ostream &OS) const
LatticeVal getValueState(LatticeKey Key)
getValueState - Return the LatticeVal object corresponding to the given value from the ValueState map...
SparseSolver(AbstractLatticeFunction< LatticeKey, LatticeVal > *Lattice)
SparseSolver(const SparseSolver &)=delete
void MarkBlockExecutable(BasicBlock *BB)
MarkBlockExecutable - This method can be used by clients to mark all of the blocks that are known to ...
void Solve()
Solve - Solve for constants and executable blocks.
LatticeVal getExistingValueState(LatticeKey Key) const
getExistingValueState - Return the LatticeVal object corresponding to the given value from the ValueS...
bool isBlockExecutable(BasicBlock *BB) const
isBlockExecutable - Return true if there are any known feasible edges into the basic block.
SparseSolver & operator=(const SparseSolver &)=delete
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
LLVM Value Representation.
Definition: Value.h:74
iterator_range< user_iterator > users()
Definition: Value.h:421
StringRef getName() const
Return a constant reference to the value's name.
Definition: Value.cpp:308
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
Key
PAL metadata keys.
@ C
The default llvm calling convention, compatible with C.
Definition: CallingConv.h:34
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:163
A template for translating between LLVM Values and LatticeKeys.