LLVM  6.0.0svn
AArch64PromoteConstant.cpp
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1 //==- AArch64PromoteConstant.cpp - Promote constant to global for AArch64 --==//
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 AArch64PromoteConstant pass which promotes constants
11 // to global variables when this is likely to be more efficient. Currently only
12 // types related to constant vector (i.e., constant vector, array of constant
13 // vectors, constant structure with a constant vector field, etc.) are promoted
14 // to global variables. Constant vectors are likely to be lowered in target
15 // constant pool during instruction selection already; therefore, the access
16 // will remain the same (memory load), but the structure types are not split
17 // into different constant pool accesses for each field. A bonus side effect is
18 // that created globals may be merged by the global merge pass.
19 //
20 // FIXME: This pass may be useful for other targets too.
21 //===----------------------------------------------------------------------===//
22 
23 #include "AArch64.h"
24 #include "llvm/ADT/DenseMap.h"
25 #include "llvm/ADT/SmallVector.h"
26 #include "llvm/ADT/Statistic.h"
27 #include "llvm/IR/BasicBlock.h"
28 #include "llvm/IR/Constant.h"
29 #include "llvm/IR/Constants.h"
30 #include "llvm/IR/Dominators.h"
31 #include "llvm/IR/Function.h"
32 #include "llvm/IR/GlobalValue.h"
33 #include "llvm/IR/GlobalVariable.h"
34 #include "llvm/IR/IRBuilder.h"
35 #include "llvm/IR/InlineAsm.h"
36 #include "llvm/IR/InstIterator.h"
37 #include "llvm/IR/Instruction.h"
38 #include "llvm/IR/Instructions.h"
39 #include "llvm/IR/IntrinsicInst.h"
40 #include "llvm/IR/Module.h"
41 #include "llvm/IR/Type.h"
42 #include "llvm/Pass.h"
43 #include "llvm/Support/Casting.h"
45 #include "llvm/Support/Debug.h"
47 #include <algorithm>
48 #include <cassert>
49 #include <utility>
50 
51 using namespace llvm;
52 
53 #define DEBUG_TYPE "aarch64-promote-const"
54 
55 // Stress testing mode - disable heuristics.
56 static cl::opt<bool> Stress("aarch64-stress-promote-const", cl::Hidden,
57  cl::desc("Promote all vector constants"));
58 
59 STATISTIC(NumPromoted, "Number of promoted constants");
60 STATISTIC(NumPromotedUses, "Number of promoted constants uses");
61 
62 //===----------------------------------------------------------------------===//
63 // AArch64PromoteConstant
64 //===----------------------------------------------------------------------===//
65 
66 namespace {
67 
68 /// Promotes interesting constant into global variables.
69 /// The motivating example is:
70 /// static const uint16_t TableA[32] = {
71 /// 41944, 40330, 38837, 37450, 36158, 34953, 33826, 32768,
72 /// 31776, 30841, 29960, 29128, 28340, 27595, 26887, 26215,
73 /// 25576, 24967, 24386, 23832, 23302, 22796, 22311, 21846,
74 /// 21400, 20972, 20561, 20165, 19785, 19419, 19066, 18725,
75 /// };
76 ///
77 /// uint8x16x4_t LoadStatic(void) {
78 /// uint8x16x4_t ret;
79 /// ret.val[0] = vld1q_u16(TableA + 0);
80 /// ret.val[1] = vld1q_u16(TableA + 8);
81 /// ret.val[2] = vld1q_u16(TableA + 16);
82 /// ret.val[3] = vld1q_u16(TableA + 24);
83 /// return ret;
84 /// }
85 ///
86 /// The constants in this example are folded into the uses. Thus, 4 different
87 /// constants are created.
88 ///
89 /// As their type is vector the cheapest way to create them is to load them
90 /// for the memory.
91 ///
92 /// Therefore the final assembly final has 4 different loads. With this pass
93 /// enabled, only one load is issued for the constants.
94 class AArch64PromoteConstant : public ModulePass {
95 public:
96  struct PromotedConstant {
97  bool ShouldConvert = false;
98  GlobalVariable *GV = nullptr;
99  };
100  using PromotionCacheTy = SmallDenseMap<Constant *, PromotedConstant, 16>;
101 
102  struct UpdateRecord {
103  Constant *C;
104  Instruction *User;
105  unsigned Op;
106 
107  UpdateRecord(Constant *C, Instruction *User, unsigned Op)
108  : C(C), User(User), Op(Op) {}
109  };
110 
111  static char ID;
112 
113  AArch64PromoteConstant() : ModulePass(ID) {
115  }
116 
117  StringRef getPassName() const override { return "AArch64 Promote Constant"; }
118 
119  /// Iterate over the functions and promote the interesting constants into
120  /// global variables with module scope.
121  bool runOnModule(Module &M) override {
122  DEBUG(dbgs() << getPassName() << '\n');
123  if (skipModule(M))
124  return false;
125  bool Changed = false;
126  PromotionCacheTy PromotionCache;
127  for (auto &MF : M) {
128  Changed |= runOnFunction(MF, PromotionCache);
129  }
130  return Changed;
131  }
132 
133 private:
134  /// Look for interesting constants used within the given function.
135  /// Promote them into global variables, load these global variables within
136  /// the related function, so that the number of inserted load is minimal.
137  bool runOnFunction(Function &F, PromotionCacheTy &PromotionCache);
138 
139  // This transformation requires dominator info
140  void getAnalysisUsage(AnalysisUsage &AU) const override {
141  AU.setPreservesCFG();
144  }
145 
146  /// Type to store a list of Uses.
148  /// Map an insertion point to all the uses it dominates.
149  using InsertionPoints = DenseMap<Instruction *, Uses>;
150 
151  /// Find the closest point that dominates the given Use.
152  Instruction *findInsertionPoint(Instruction &User, unsigned OpNo);
153 
154  /// Check if the given insertion point is dominated by an existing
155  /// insertion point.
156  /// If true, the given use is added to the list of dominated uses for
157  /// the related existing point.
158  /// \param NewPt the insertion point to be checked
159  /// \param User the user of the constant
160  /// \param OpNo the operand number of the use
161  /// \param InsertPts existing insertion points
162  /// \pre NewPt and all instruction in InsertPts belong to the same function
163  /// \return true if one of the insertion point in InsertPts dominates NewPt,
164  /// false otherwise
165  bool isDominated(Instruction *NewPt, Instruction *User, unsigned OpNo,
166  InsertionPoints &InsertPts);
167 
168  /// Check if the given insertion point can be merged with an existing
169  /// insertion point in a common dominator.
170  /// If true, the given use is added to the list of the created insertion
171  /// point.
172  /// \param NewPt the insertion point to be checked
173  /// \param User the user of the constant
174  /// \param OpNo the operand number of the use
175  /// \param InsertPts existing insertion points
176  /// \pre NewPt and all instruction in InsertPts belong to the same function
177  /// \pre isDominated returns false for the exact same parameters.
178  /// \return true if it exists an insertion point in InsertPts that could
179  /// have been merged with NewPt in a common dominator,
180  /// false otherwise
181  bool tryAndMerge(Instruction *NewPt, Instruction *User, unsigned OpNo,
182  InsertionPoints &InsertPts);
183 
184  /// Compute the minimal insertion points to dominates all the interesting
185  /// uses of value.
186  /// Insertion points are group per function and each insertion point
187  /// contains a list of all the uses it dominates within the related function
188  /// \param User the user of the constant
189  /// \param OpNo the operand number of the constant
190  /// \param[out] InsertPts output storage of the analysis
191  void computeInsertionPoint(Instruction *User, unsigned OpNo,
192  InsertionPoints &InsertPts);
193 
194  /// Insert a definition of a new global variable at each point contained in
195  /// InsPtsPerFunc and update the related uses (also contained in
196  /// InsPtsPerFunc).
197  void insertDefinitions(Function &F, GlobalVariable &GV,
198  InsertionPoints &InsertPts);
199 
200  /// Do the constant promotion indicated by the Updates records, keeping track
201  /// of globals in PromotionCache.
202  void promoteConstants(Function &F, SmallVectorImpl<UpdateRecord> &Updates,
203  PromotionCacheTy &PromotionCache);
204 
205  /// Transfer the list of dominated uses of IPI to NewPt in InsertPts.
206  /// Append Use to this list and delete the entry of IPI in InsertPts.
207  static void appendAndTransferDominatedUses(Instruction *NewPt,
208  Instruction *User, unsigned OpNo,
209  InsertionPoints::iterator &IPI,
210  InsertionPoints &InsertPts) {
211  // Record the dominated use.
212  IPI->second.emplace_back(User, OpNo);
213  // Transfer the dominated uses of IPI to NewPt
214  // Inserting into the DenseMap may invalidate existing iterator.
215  // Keep a copy of the key to find the iterator to erase. Keep a copy of the
216  // value so that we don't have to dereference IPI->second.
217  Instruction *OldInstr = IPI->first;
218  Uses OldUses = std::move(IPI->second);
219  InsertPts[NewPt] = std::move(OldUses);
220  // Erase IPI.
221  InsertPts.erase(OldInstr);
222  }
223 };
224 
225 } // end anonymous namespace
226 
228 
229 INITIALIZE_PASS_BEGIN(AArch64PromoteConstant, "aarch64-promote-const",
230  "AArch64 Promote Constant Pass", false, false)
232 INITIALIZE_PASS_END(AArch64PromoteConstant, "aarch64-promote-const",
233  "AArch64 Promote Constant Pass", false, false)
234 
236  return new AArch64PromoteConstant();
237 }
238 
239 /// Check if the given type uses a vector type.
240 static bool isConstantUsingVectorTy(const Type *CstTy) {
241  if (CstTy->isVectorTy())
242  return true;
243  if (CstTy->isStructTy()) {
244  for (unsigned EltIdx = 0, EndEltIdx = CstTy->getStructNumElements();
245  EltIdx < EndEltIdx; ++EltIdx)
246  if (isConstantUsingVectorTy(CstTy->getStructElementType(EltIdx)))
247  return true;
248  } else if (CstTy->isArrayTy())
250  return false;
251 }
252 
253 /// Check if the given use (Instruction + OpIdx) of Cst should be converted into
254 /// a load of a global variable initialized with Cst.
255 /// A use should be converted if it is legal to do so.
256 /// For instance, it is not legal to turn the mask operand of a shuffle vector
257 /// into a load of a global variable.
258 static bool shouldConvertUse(const Constant *Cst, const Instruction *Instr,
259  unsigned OpIdx) {
260  // shufflevector instruction expects a const for the mask argument, i.e., the
261  // third argument. Do not promote this use in that case.
262  if (isa<const ShuffleVectorInst>(Instr) && OpIdx == 2)
263  return false;
264 
265  // extractvalue instruction expects a const idx.
266  if (isa<const ExtractValueInst>(Instr) && OpIdx > 0)
267  return false;
268 
269  // extractvalue instruction expects a const idx.
270  if (isa<const InsertValueInst>(Instr) && OpIdx > 1)
271  return false;
272 
273  if (isa<const AllocaInst>(Instr) && OpIdx > 0)
274  return false;
275 
276  // Alignment argument must be constant.
277  if (isa<const LoadInst>(Instr) && OpIdx > 0)
278  return false;
279 
280  // Alignment argument must be constant.
281  if (isa<const StoreInst>(Instr) && OpIdx > 1)
282  return false;
283 
284  // Index must be constant.
285  if (isa<const GetElementPtrInst>(Instr) && OpIdx > 0)
286  return false;
287 
288  // Personality function and filters must be constant.
289  // Give up on that instruction.
290  if (isa<const LandingPadInst>(Instr))
291  return false;
292 
293  // Switch instruction expects constants to compare to.
294  if (isa<const SwitchInst>(Instr))
295  return false;
296 
297  // Expected address must be a constant.
298  if (isa<const IndirectBrInst>(Instr))
299  return false;
300 
301  // Do not mess with intrinsics.
302  if (isa<const IntrinsicInst>(Instr))
303  return false;
304 
305  // Do not mess with inline asm.
306  const CallInst *CI = dyn_cast<const CallInst>(Instr);
307  return !(CI && isa<const InlineAsm>(CI->getCalledValue()));
308 }
309 
310 /// Check if the given Cst should be converted into
311 /// a load of a global variable initialized with Cst.
312 /// A constant should be converted if it is likely that the materialization of
313 /// the constant will be tricky. Thus, we give up on zero or undef values.
314 ///
315 /// \todo Currently, accept only vector related types.
316 /// Also we give up on all simple vector type to keep the existing
317 /// behavior. Otherwise, we should push here all the check of the lowering of
318 /// BUILD_VECTOR. By giving up, we lose the potential benefit of merging
319 /// constant via global merge and the fact that the same constant is stored
320 /// only once with this method (versus, as many function that uses the constant
321 /// for the regular approach, even for float).
322 /// Again, the simplest solution would be to promote every
323 /// constant and rematerialize them when they are actually cheap to create.
324 static bool shouldConvertImpl(const Constant *Cst) {
325  if (isa<const UndefValue>(Cst))
326  return false;
327 
328  // FIXME: In some cases, it may be interesting to promote in memory
329  // a zero initialized constant.
330  // E.g., when the type of Cst require more instructions than the
331  // adrp/add/load sequence or when this sequence can be shared by several
332  // instances of Cst.
333  // Ideally, we could promote this into a global and rematerialize the constant
334  // when it was a bad idea.
335  if (Cst->isZeroValue())
336  return false;
337 
338  if (Stress)
339  return true;
340 
341  // FIXME: see function \todo
342  if (Cst->getType()->isVectorTy())
343  return false;
344  return isConstantUsingVectorTy(Cst->getType());
345 }
346 
347 static bool
350  auto Converted = PromotionCache.insert(
351  std::make_pair(&C, AArch64PromoteConstant::PromotedConstant()));
352  if (Converted.second)
353  Converted.first->second.ShouldConvert = shouldConvertImpl(&C);
354  return Converted.first->second.ShouldConvert;
355 }
356 
357 Instruction *AArch64PromoteConstant::findInsertionPoint(Instruction &User,
358  unsigned OpNo) {
359  // If this user is a phi, the insertion point is in the related
360  // incoming basic block.
361  if (PHINode *PhiInst = dyn_cast<PHINode>(&User))
362  return PhiInst->getIncomingBlock(OpNo)->getTerminator();
363 
364  return &User;
365 }
366 
367 bool AArch64PromoteConstant::isDominated(Instruction *NewPt, Instruction *User,
368  unsigned OpNo,
369  InsertionPoints &InsertPts) {
370  DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>(
371  *NewPt->getParent()->getParent()).getDomTree();
372 
373  // Traverse all the existing insertion points and check if one is dominating
374  // NewPt. If it is, remember that.
375  for (auto &IPI : InsertPts) {
376  if (NewPt == IPI.first || DT.dominates(IPI.first, NewPt) ||
377  // When IPI.first is a terminator instruction, DT may think that
378  // the result is defined on the edge.
379  // Here we are testing the insertion point, not the definition.
380  (IPI.first->getParent() != NewPt->getParent() &&
381  DT.dominates(IPI.first->getParent(), NewPt->getParent()))) {
382  // No need to insert this point. Just record the dominated use.
383  DEBUG(dbgs() << "Insertion point dominated by:\n");
384  DEBUG(IPI.first->print(dbgs()));
385  DEBUG(dbgs() << '\n');
386  IPI.second.emplace_back(User, OpNo);
387  return true;
388  }
389  }
390  return false;
391 }
392 
393 bool AArch64PromoteConstant::tryAndMerge(Instruction *NewPt, Instruction *User,
394  unsigned OpNo,
395  InsertionPoints &InsertPts) {
396  DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>(
397  *NewPt->getParent()->getParent()).getDomTree();
398  BasicBlock *NewBB = NewPt->getParent();
399 
400  // Traverse all the existing insertion point and check if one is dominated by
401  // NewPt and thus useless or can be combined with NewPt into a common
402  // dominator.
403  for (InsertionPoints::iterator IPI = InsertPts.begin(),
404  EndIPI = InsertPts.end();
405  IPI != EndIPI; ++IPI) {
406  BasicBlock *CurBB = IPI->first->getParent();
407  if (NewBB == CurBB) {
408  // Instructions are in the same block.
409  // By construction, NewPt is dominating the other.
410  // Indeed, isDominated returned false with the exact same arguments.
411  DEBUG(dbgs() << "Merge insertion point with:\n");
412  DEBUG(IPI->first->print(dbgs()));
413  DEBUG(dbgs() << "\nat considered insertion point.\n");
414  appendAndTransferDominatedUses(NewPt, User, OpNo, IPI, InsertPts);
415  return true;
416  }
417 
418  // Look for a common dominator
419  BasicBlock *CommonDominator = DT.findNearestCommonDominator(NewBB, CurBB);
420  // If none exists, we cannot merge these two points.
421  if (!CommonDominator)
422  continue;
423 
424  if (CommonDominator != NewBB) {
425  // By construction, the CommonDominator cannot be CurBB.
426  assert(CommonDominator != CurBB &&
427  "Instruction has not been rejected during isDominated check!");
428  // Take the last instruction of the CommonDominator as insertion point
429  NewPt = CommonDominator->getTerminator();
430  }
431  // else, CommonDominator is the block of NewBB, hence NewBB is the last
432  // possible insertion point in that block.
433  DEBUG(dbgs() << "Merge insertion point with:\n");
434  DEBUG(IPI->first->print(dbgs()));
435  DEBUG(dbgs() << '\n');
436  DEBUG(NewPt->print(dbgs()));
437  DEBUG(dbgs() << '\n');
438  appendAndTransferDominatedUses(NewPt, User, OpNo, IPI, InsertPts);
439  return true;
440  }
441  return false;
442 }
443 
444 void AArch64PromoteConstant::computeInsertionPoint(
445  Instruction *User, unsigned OpNo, InsertionPoints &InsertPts) {
446  DEBUG(dbgs() << "Considered use, opidx " << OpNo << ":\n");
447  DEBUG(User->print(dbgs()));
448  DEBUG(dbgs() << '\n');
449 
450  Instruction *InsertionPoint = findInsertionPoint(*User, OpNo);
451 
452  DEBUG(dbgs() << "Considered insertion point:\n");
453  DEBUG(InsertionPoint->print(dbgs()));
454  DEBUG(dbgs() << '\n');
455 
456  if (isDominated(InsertionPoint, User, OpNo, InsertPts))
457  return;
458  // This insertion point is useful, check if we can merge some insertion
459  // point in a common dominator or if NewPt dominates an existing one.
460  if (tryAndMerge(InsertionPoint, User, OpNo, InsertPts))
461  return;
462 
463  DEBUG(dbgs() << "Keep considered insertion point\n");
464 
465  // It is definitely useful by its own
466  InsertPts[InsertionPoint].emplace_back(User, OpNo);
467 }
468 
470  AArch64PromoteConstant::PromotedConstant &PC) {
471  assert(PC.ShouldConvert &&
472  "Expected that we should convert this to a global");
473  if (PC.GV)
474  return;
475  PC.GV = new GlobalVariable(
476  *F.getParent(), C.getType(), true, GlobalValue::InternalLinkage, nullptr,
477  "_PromotedConst", nullptr, GlobalVariable::NotThreadLocal);
478  PC.GV->setInitializer(&C);
479  DEBUG(dbgs() << "Global replacement: ");
480  DEBUG(PC.GV->print(dbgs()));
481  DEBUG(dbgs() << '\n');
482  ++NumPromoted;
483 }
484 
485 void AArch64PromoteConstant::insertDefinitions(Function &F,
486  GlobalVariable &PromotedGV,
487  InsertionPoints &InsertPts) {
488 #ifndef NDEBUG
489  // Do more checking for debug purposes.
490  DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>(F).getDomTree();
491 #endif
492  assert(!InsertPts.empty() && "Empty uses does not need a definition");
493 
494  for (const auto &IPI : InsertPts) {
495  // Create the load of the global variable.
496  IRBuilder<> Builder(IPI.first);
497  LoadInst *LoadedCst = Builder.CreateLoad(&PromotedGV);
498  DEBUG(dbgs() << "**********\n");
499  DEBUG(dbgs() << "New def: ");
500  DEBUG(LoadedCst->print(dbgs()));
501  DEBUG(dbgs() << '\n');
502 
503  // Update the dominated uses.
504  for (auto Use : IPI.second) {
505 #ifndef NDEBUG
506  assert(DT.dominates(LoadedCst,
507  findInsertionPoint(*Use.first, Use.second)) &&
508  "Inserted definition does not dominate all its uses!");
509 #endif
510  DEBUG({
511  dbgs() << "Use to update " << Use.second << ":";
512  Use.first->print(dbgs());
513  dbgs() << '\n';
514  });
515  Use.first->setOperand(Use.second, LoadedCst);
516  ++NumPromotedUses;
517  }
518  }
519 }
520 
521 void AArch64PromoteConstant::promoteConstants(
523  PromotionCacheTy &PromotionCache) {
524  // Promote the constants.
525  for (auto U = Updates.begin(), E = Updates.end(); U != E;) {
526  DEBUG(dbgs() << "** Compute insertion points **\n");
527  auto First = U;
528  Constant *C = First->C;
529  InsertionPoints InsertPts;
530  do {
531  computeInsertionPoint(U->User, U->Op, InsertPts);
532  } while (++U != E && U->C == C);
533 
534  auto &Promotion = PromotionCache[C];
535  ensurePromotedGV(F, *C, Promotion);
536  insertDefinitions(F, *Promotion.GV, InsertPts);
537  }
538 }
539 
541  PromotionCacheTy &PromotionCache) {
542  // Look for instructions using constant vector. Promote that constant to a
543  // global variable. Create as few loads of this variable as possible and
544  // update the uses accordingly.
546  for (Instruction &I : instructions(&F)) {
547  // Traverse the operand, looking for constant vectors. Replace them by a
548  // load of a global variable of constant vector type.
549  for (Use &U : I.operands()) {
550  Constant *Cst = dyn_cast<Constant>(U);
551  // There is no point in promoting global values as they are already
552  // global. Do not promote constant expressions either, as they may
553  // require some code expansion.
554  if (!Cst || isa<GlobalValue>(Cst) || isa<ConstantExpr>(Cst))
555  continue;
556 
557  // Check if this constant is worth promoting.
558  if (!shouldConvert(*Cst, PromotionCache))
559  continue;
560 
561  // Check if this use should be promoted.
562  unsigned OpNo = &U - I.op_begin();
563  if (!shouldConvertUse(Cst, &I, OpNo))
564  continue;
565 
566  Updates.emplace_back(Cst, &I, OpNo);
567  }
568  }
569 
570  if (Updates.empty())
571  return false;
572 
573  promoteConstants(F, Updates, PromotionCache);
574  return true;
575 }
Pass interface - Implemented by all &#39;passes&#39;.
Definition: Pass.h:81
uint64_t CallInst * C
AnalysisUsage & addPreserved()
Add the specified Pass class to the set of analyses preserved by this pass.
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
static bool isConstantUsingVectorTy(const Type *CstTy)
Check if the given type uses a vector type.
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
static bool shouldConvertImpl(const Constant *Cst)
Check if the given Cst should be converted into a load of a global variable initialized with Cst...
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:63
This class represents a function call, abstracting a target machine&#39;s calling convention.
NodeT * findNearestCommonDominator(NodeT *A, NodeT *B) const
findNearestCommonDominator - Find nearest common dominator basic block for basic block A and B...
STATISTIC(NumFunctions, "Total number of functions")
F(f)
Type * getStructElementType(unsigned N) const
Definition: DerivedTypes.h:333
An instruction for reading from memory.
Definition: Instructions.h:164
bool isVectorTy() const
True if this is an instance of VectorType.
Definition: Type.h:227
ModulePass * createAArch64PromoteConstantPass()
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: DenseMap.h:191
AnalysisUsage & addRequired()
#define INITIALIZE_PASS_DEPENDENCY(depName)
Definition: PassSupport.h:51
void setInitializer(Constant *InitVal)
setInitializer - Sets the initializer for this global variable, removing any existing initializer if ...
Definition: Globals.cpp:340
A Use represents the edge between a Value definition and its users.
Definition: Use.h:56
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:42
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:668
static bool shouldConvert(Constant &C, AArch64PromoteConstant::PromotionCacheTy &PromotionCache)
static cl::opt< bool > Stress("aarch64-stress-promote-const", cl::Hidden, cl::desc("Promote all vector constants"))
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree...
Definition: Dominators.h:140
bool isZeroValue() const
Return true if the value is negative zero or null value.
Definition: Constants.cpp:66
LoadInst * CreateLoad(Value *Ptr, const char *Name)
Definition: IRBuilder.h:1168
static bool runOnFunction(Function &F, bool PostInlining)
const Value * getCalledValue() const
Get a pointer to the function that is invoked by this instruction.
void initializeAArch64PromoteConstantPass(PassRegistry &)
LLVM Basic Block Representation.
Definition: BasicBlock.h:59
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This is an important base class in LLVM.
Definition: Constant.h:42
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:116
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Represent the analysis usage information of a pass.
void print(raw_ostream &O, bool IsForDebug=false) const
Implement operator<< on Value.
Definition: AsmWriter.cpp:3494
unsigned getStructNumElements() const
Definition: DerivedTypes.h:329
INITIALIZE_PASS_END(RegBankSelect, DEBUG_TYPE, "Assign register bank of generic virtual registers", false, false) RegBankSelect
static bool shouldConvertUse(const Constant *Cst, const Instruction *Instr, unsigned OpIdx)
Check if the given use (Instruction + OpIdx) of Cst should be converted into a load of a global varia...
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:864
bool dominates(const Instruction *Def, const Use &U) const
Return true if Def dominates a use in User.
Definition: Dominators.cpp:239
Module.h This file contains the declarations for the Module class.
void setPreservesCFG()
This function should be called by the pass, iff they do not:
Definition: Pass.cpp:285
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:120
void emplace_back(ArgTypes &&... Args)
Definition: SmallVector.h:656
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:61
const Function * getParent() const
Return the enclosing method, or null if none.
Definition: BasicBlock.h:108
#define I(x, y, z)
Definition: MD5.cpp:58
ModulePass class - This class is used to implement unstructured interprocedural optimizations and ana...
Definition: Pass.h:225
LLVM_NODISCARD std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type dyn_cast(const Y &Val)
Definition: Casting.h:323
Rename collisions when linking (static functions).
Definition: GlobalValue.h:56
INITIALIZE_PASS_BEGIN(AArch64PromoteConstant, "aarch64-promote-const", "AArch64 Promote Constant Pass", false, false) INITIALIZE_PASS_END(AArch64PromoteConstant
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
aarch64 promote const
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:556
#define DEBUG(X)
Definition: Debug.h:118
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
inst_range instructions(Function *F)
Definition: InstIterator.h:134
Type * getArrayElementType() const
Definition: Type.h:362
Legacy analysis pass which computes a DominatorTree.
Definition: Dominators.h:267
const TerminatorInst * getTerminator() const LLVM_READONLY
Returns the terminator instruction if the block is well formed or null if the block is not well forme...
Definition: BasicBlock.cpp:120
static void ensurePromotedGV(Function &F, Constant &C, AArch64PromoteConstant::PromotedConstant &PC)
bool isStructTy() const
True if this is an instance of StructType.
Definition: Type.h:215
bool isArrayTy() const
True if this is an instance of ArrayType.
Definition: Type.h:218
const BasicBlock * getParent() const
Definition: Instruction.h:66