LLVM  7.0.0svn
HexagonVectorLoopCarriedReuse.cpp
Go to the documentation of this file.
1 //===- HexagonVectorLoopCarriedReuse.cpp ----------------------------------===//
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 pass removes the computation of provably redundant expressions that have
11 // been computed earlier in a previous iteration. It relies on the use of PHIs
12 // to identify loop carried dependences. This is scalar replacement for vector
13 // types.
14 //
15 //-----------------------------------------------------------------------------
16 // Motivation: Consider the case where we have the following loop structure.
17 //
18 // Loop:
19 // t0 = a[i];
20 // t1 = f(t0);
21 // t2 = g(t1);
22 // ...
23 // t3 = a[i+1];
24 // t4 = f(t3);
25 // t5 = g(t4);
26 // t6 = op(t2, t5)
27 // cond_branch <Loop>
28 //
29 // This can be converted to
30 // t00 = a[0];
31 // t10 = f(t00);
32 // t20 = g(t10);
33 // Loop:
34 // t2 = t20;
35 // t3 = a[i+1];
36 // t4 = f(t3);
37 // t5 = g(t4);
38 // t6 = op(t2, t5)
39 // t20 = t5
40 // cond_branch <Loop>
41 //
42 // SROA does a good job of reusing a[i+1] as a[i] in the next iteration.
43 // Such a loop comes to this pass in the following form.
44 //
45 // LoopPreheader:
46 // X0 = a[0];
47 // Loop:
48 // X2 = PHI<(X0, LoopPreheader), (X1, Loop)>
49 // t1 = f(X2) <-- I1
50 // t2 = g(t1)
51 // ...
52 // X1 = a[i+1]
53 // t4 = f(X1) <-- I2
54 // t5 = g(t4)
55 // t6 = op(t2, t5)
56 // cond_branch <Loop>
57 //
58 // In this pass, we look for PHIs such as X2 whose incoming values come only
59 // from the Loop Preheader and over the backedge and additionaly, both these
60 // values are the results of the same operation in terms of opcode. We call such
61 // a PHI node a dependence chain or DepChain. In this case, the dependence of X2
62 // over X1 is carried over only one iteration and so the DepChain is only one
63 // PHI node long.
64 //
65 // Then, we traverse the uses of the PHI (X2) and the uses of the value of the
66 // PHI coming over the backedge (X1). We stop at the first pair of such users
67 // I1 (of X2) and I2 (of X1) that meet the following conditions.
68 // 1. I1 and I2 are the same operation, but with different operands.
69 // 2. X2 and X1 are used at the same operand number in the two instructions.
70 // 3. All other operands Op1 of I1 and Op2 of I2 are also such that there is a
71 // a DepChain from Op1 to Op2 of the same length as that between X2 and X1.
72 //
73 // We then make the following transformation
74 // LoopPreheader:
75 // X0 = a[0];
76 // Y0 = f(X0);
77 // Loop:
78 // X2 = PHI<(X0, LoopPreheader), (X1, Loop)>
79 // Y2 = PHI<(Y0, LoopPreheader), (t4, Loop)>
80 // t1 = f(X2) <-- Will be removed by DCE.
81 // t2 = g(Y2)
82 // ...
83 // X1 = a[i+1]
84 // t4 = f(X1)
85 // t5 = g(t4)
86 // t6 = op(t2, t5)
87 // cond_branch <Loop>
88 //
89 // We proceed until we cannot find any more such instructions I1 and I2.
90 //
91 // --- DepChains & Loop carried dependences ---
92 // Consider a single basic block loop such as
93 //
94 // LoopPreheader:
95 // X0 = ...
96 // Y0 = ...
97 // Loop:
98 // X2 = PHI<(X0, LoopPreheader), (X1, Loop)>
99 // Y2 = PHI<(Y0, LoopPreheader), (X2, Loop)>
100 // ...
101 // X1 = ...
102 // ...
103 // cond_branch <Loop>
104 //
105 // Then there is a dependence between X2 and X1 that goes back one iteration,
106 // i.e. X1 is used as X2 in the very next iteration. We represent this as a
107 // DepChain from X2 to X1 (X2->X1).
108 // Similarly, there is a dependence between Y2 and X1 that goes back two
109 // iterations. X1 is used as Y2 two iterations after it is computed. This is
110 // represented by a DepChain as (Y2->X2->X1).
111 //
112 // A DepChain has the following properties.
113 // 1. Num of edges in DepChain = Number of Instructions in DepChain = Number of
114 // iterations of carried dependence + 1.
115 // 2. All instructions in the DepChain except the last are PHIs.
116 //
117 //===----------------------------------------------------------------------===//
118 
119 #include "llvm/ADT/SetVector.h"
120 #include "llvm/ADT/SmallVector.h"
121 #include "llvm/ADT/Statistic.h"
122 #include "llvm/Analysis/LoopInfo.h"
123 #include "llvm/Analysis/LoopPass.h"
124 #include "llvm/IR/BasicBlock.h"
125 #include "llvm/IR/DerivedTypes.h"
126 #include "llvm/IR/IRBuilder.h"
127 #include "llvm/IR/Instruction.h"
128 #include "llvm/IR/Instructions.h"
129 #include "llvm/IR/IntrinsicInst.h"
130 #include "llvm/IR/Intrinsics.h"
131 #include "llvm/IR/Use.h"
132 #include "llvm/IR/User.h"
133 #include "llvm/IR/Value.h"
134 #include "llvm/Pass.h"
135 #include "llvm/Support/Casting.h"
137 #include "llvm/Support/Compiler.h"
138 #include "llvm/Support/Debug.h"
140 #include "llvm/Transforms/Scalar.h"
141 #include <algorithm>
142 #include <cassert>
143 #include <cstddef>
144 #include <map>
145 #include <memory>
146 #include <set>
147 
148 using namespace llvm;
149 
150 #define DEBUG_TYPE "hexagon-vlcr"
151 
152 STATISTIC(HexagonNumVectorLoopCarriedReuse,
153  "Number of values that were reused from a previous iteration.");
154 
155 static cl::opt<int> HexagonVLCRIterationLim("hexagon-vlcr-iteration-lim",
156  cl::Hidden,
157  cl::desc("Maximum distance of loop carried dependences that are handled"),
159 
160 namespace llvm {
161 
164 
165 } // end namespace llvm
166 
167 namespace {
168 
169  // See info about DepChain in the comments at the top of this file.
170  using ChainOfDependences = SmallVector<Instruction *, 4>;
171 
172  class DepChain {
173  ChainOfDependences Chain;
174 
175  public:
176  bool isIdentical(DepChain &Other) const {
177  if (Other.size() != size())
178  return false;
179  ChainOfDependences &OtherChain = Other.getChain();
180  for (int i = 0; i < size(); ++i) {
181  if (Chain[i] != OtherChain[i])
182  return false;
183  }
184  return true;
185  }
186 
187  ChainOfDependences &getChain() {
188  return Chain;
189  }
190 
191  int size() const {
192  return Chain.size();
193  }
194 
195  void clear() {
196  Chain.clear();
197  }
198 
199  void push_back(Instruction *I) {
200  Chain.push_back(I);
201  }
202 
203  int iterations() const {
204  return size() - 1;
205  }
206 
207  Instruction *front() const {
208  return Chain.front();
209  }
210 
211  Instruction *back() const {
212  return Chain.back();
213  }
214 
215  Instruction *&operator[](const int index) {
216  return Chain[index];
217  }
218 
219  friend raw_ostream &operator<< (raw_ostream &OS, const DepChain &D);
220  };
221 
223  raw_ostream &operator<<(raw_ostream &OS, const DepChain &D) {
224  const ChainOfDependences &CD = D.Chain;
225  int ChainSize = CD.size();
226  OS << "**DepChain Start::**\n";
227  for (int i = 0; i < ChainSize -1; ++i) {
228  OS << *(CD[i]) << " -->\n";
229  }
230  OS << *CD[ChainSize-1] << "\n";
231  return OS;
232  }
233 
234  struct ReuseValue {
235  Instruction *Inst2Replace = nullptr;
236 
237  // In the new PHI node that we'll construct this is the value that'll be
238  // used over the backedge. This is teh value that gets reused from a
239  // previous iteration.
240  Instruction *BackedgeInst = nullptr;
241 
242  ReuseValue() = default;
243 
244  void reset() { Inst2Replace = nullptr; BackedgeInst = nullptr; }
245  bool isDefined() { return Inst2Replace != nullptr; }
246  };
247 
249  raw_ostream &operator<<(raw_ostream &OS, const ReuseValue &RU) {
250  OS << "** ReuseValue ***\n";
251  OS << "Instruction to Replace: " << *(RU.Inst2Replace) << "\n";
252  OS << "Backedge Instruction: " << *(RU.BackedgeInst) << "\n";
253  return OS;
254  }
255 
256  class HexagonVectorLoopCarriedReuse : public LoopPass {
257  public:
258  static char ID;
259 
260  explicit HexagonVectorLoopCarriedReuse() : LoopPass(ID) {
263  }
264 
265  StringRef getPassName() const override {
266  return "Hexagon-specific loop carried reuse for HVX vectors";
267  }
268 
269  void getAnalysisUsage(AnalysisUsage &AU) const override {
274  AU.setPreservesCFG();
275  }
276 
277  bool runOnLoop(Loop *L, LPPassManager &LPM) override;
278 
279  private:
280  SetVector<DepChain *> Dependences;
281  std::set<Instruction *> ReplacedInsts;
282  Loop *CurLoop;
283  ReuseValue ReuseCandidate;
284 
285  bool doVLCR();
286  void findLoopCarriedDeps();
287  void findValueToReuse();
288  void findDepChainFromPHI(Instruction *I, DepChain &D);
289  void reuseValue();
290  Value *findValueInBlock(Value *Op, BasicBlock *BB);
291  bool isDepChainBtwn(Instruction *I1, Instruction *I2, int Iters);
292  DepChain *getDepChainBtwn(Instruction *I1, Instruction *I2);
293  bool isEquivalentOperation(Instruction *I1, Instruction *I2);
294  bool canReplace(Instruction *I);
295  };
296 
297 } // end anonymous namespace
298 
300 
301 INITIALIZE_PASS_BEGIN(HexagonVectorLoopCarriedReuse, "hexagon-vlcr",
302  "Hexagon-specific predictive commoning for HVX vectors", false, false)
304 INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
305 INITIALIZE_PASS_DEPENDENCY(LCSSAWrapperPass)
306 INITIALIZE_PASS_END(HexagonVectorLoopCarriedReuse, "hexagon-vlcr",
307  "Hexagon-specific predictive commoning for HVX vectors", false, false)
308 
309 bool HexagonVectorLoopCarriedReuse::runOnLoop(Loop *L, LPPassManager &LPM) {
310  if (skipLoop(L))
311  return false;
312 
313  if (!L->getLoopPreheader())
314  return false;
315 
316  // Work only on innermost loops.
317  if (!L->getSubLoops().empty())
318  return false;
319 
320  // Work only on single basic blocks loops.
321  if (L->getNumBlocks() != 1)
322  return false;
323 
324  CurLoop = L;
325 
326  return doVLCR();
327 }
328 
329 bool HexagonVectorLoopCarriedReuse::isEquivalentOperation(Instruction *I1,
330  Instruction *I2) {
331  if (!I1->isSameOperationAs(I2))
332  return false;
333  // This check is in place specifically for intrinsics. isSameOperationAs will
334  // return two for any two hexagon intrinsics because they are essentially the
335  // same instruciton (CallInst). We need to scratch the surface to see if they
336  // are calls to the same function.
337  if (CallInst *C1 = dyn_cast<CallInst>(I1)) {
338  if (CallInst *C2 = dyn_cast<CallInst>(I2)) {
339  if (C1->getCalledFunction() != C2->getCalledFunction())
340  return false;
341  }
342  }
343 
344  // If both the Instructions are of Vector Type and any of the element
345  // is integer constant, check their values too for equivalence.
346  if (I1->getType()->isVectorTy() && I2->getType()->isVectorTy()) {
347  unsigned NumOperands = I1->getNumOperands();
348  for (unsigned i = 0; i < NumOperands; ++i) {
351  if(!C1) continue;
352  assert(C2);
353  if (C1->getSExtValue() != C2->getSExtValue())
354  return false;
355  }
356  }
357 
358  return true;
359 }
360 
361 bool HexagonVectorLoopCarriedReuse::canReplace(Instruction *I) {
362  const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I);
363  if (II &&
364  (II->getIntrinsicID() == Intrinsic::hexagon_V6_hi ||
365  II->getIntrinsicID() == Intrinsic::hexagon_V6_lo)) {
366  DEBUG(dbgs() << "Not considering for reuse: " << *II << "\n");
367  return false;
368  }
369  return true;
370 }
371 void HexagonVectorLoopCarriedReuse::findValueToReuse() {
372  for (auto *D : Dependences) {
373  DEBUG(dbgs() << "Processing dependence " << *(D->front()) << "\n");
374  if (D->iterations() > HexagonVLCRIterationLim) {
375  DEBUG(dbgs() <<
376  ".. Skipping because number of iterations > than the limit\n");
377  continue;
378  }
379 
380  PHINode *PN = cast<PHINode>(D->front());
381  Instruction *BEInst = D->back();
382  int Iters = D->iterations();
383  BasicBlock *BB = PN->getParent();
384  DEBUG(dbgs() << "Checking if any uses of " << *PN << " can be reused\n");
385 
387  for (auto UI = PN->use_begin(), E = PN->use_end(); UI != E; ++UI) {
388  Use &U = *UI;
389  Instruction *User = cast<Instruction>(U.getUser());
390 
391  if (User->getParent() != BB)
392  continue;
393  if (ReplacedInsts.count(User)) {
394  DEBUG(dbgs() << *User << " has already been replaced. Skipping...\n");
395  continue;
396  }
397  if (isa<PHINode>(User))
398  continue;
399  if (User->mayHaveSideEffects())
400  continue;
401  if (!canReplace(User))
402  continue;
403 
404  PNUsers.push_back(User);
405  }
406  DEBUG(dbgs() << PNUsers.size() << " use(s) of the PHI in the block\n");
407 
408  // For each interesting use I of PN, find an Instruction BEUser that
409  // performs the same operation as I on BEInst and whose other operands,
410  // if any, can also be rematerialized in OtherBB. We stop when we find the
411  // first such Instruction BEUser. This is because once BEUser is
412  // rematerialized in OtherBB, we may find more such "fixup" opportunities
413  // in this block. So, we'll start over again.
414  for (Instruction *I : PNUsers) {
415  for (auto UI = BEInst->use_begin(), E = BEInst->use_end(); UI != E;
416  ++UI) {
417  Use &U = *UI;
418  Instruction *BEUser = cast<Instruction>(U.getUser());
419 
420  if (BEUser->getParent() != BB)
421  continue;
422  if (!isEquivalentOperation(I, BEUser))
423  continue;
424 
425  int NumOperands = I->getNumOperands();
426 
427  for (int OpNo = 0; OpNo < NumOperands; ++OpNo) {
428  Value *Op = I->getOperand(OpNo);
429  Instruction *OpInst = dyn_cast<Instruction>(Op);
430  if (!OpInst)
431  continue;
432 
433  Value *BEOp = BEUser->getOperand(OpNo);
434  Instruction *BEOpInst = dyn_cast<Instruction>(BEOp);
435 
436  if (!isDepChainBtwn(OpInst, BEOpInst, Iters)) {
437  BEUser = nullptr;
438  break;
439  }
440  }
441  if (BEUser) {
442  DEBUG(dbgs() << "Found Value for reuse.\n");
443  ReuseCandidate.Inst2Replace = I;
444  ReuseCandidate.BackedgeInst = BEUser;
445  return;
446  } else
447  ReuseCandidate.reset();
448  }
449  }
450  }
451  ReuseCandidate.reset();
452 }
453 
454 Value *HexagonVectorLoopCarriedReuse::findValueInBlock(Value *Op,
455  BasicBlock *BB) {
456  PHINode *PN = dyn_cast<PHINode>(Op);
457  assert(PN);
458  Value *ValueInBlock = PN->getIncomingValueForBlock(BB);
459  return ValueInBlock;
460 }
461 
462 void HexagonVectorLoopCarriedReuse::reuseValue() {
463  DEBUG(dbgs() << ReuseCandidate);
464  Instruction *Inst2Replace = ReuseCandidate.Inst2Replace;
465  Instruction *BEInst = ReuseCandidate.BackedgeInst;
466  int NumOperands = Inst2Replace->getNumOperands();
467  std::map<Instruction *, DepChain *> DepChains;
468  int Iterations = -1;
469  BasicBlock *LoopPH = CurLoop->getLoopPreheader();
470 
471  for (int i = 0; i < NumOperands; ++i) {
472  Instruction *I = dyn_cast<Instruction>(Inst2Replace->getOperand(i));
473  if(!I)
474  continue;
475  else {
476  Instruction *J = cast<Instruction>(BEInst->getOperand(i));
477  DepChain *D = getDepChainBtwn(I, J);
478 
479  assert(D &&
480  "No DepChain between corresponding operands in ReuseCandidate\n");
481  if (Iterations == -1)
482  Iterations = D->iterations();
483  assert(Iterations == D->iterations() && "Iterations mismatch");
484  DepChains[I] = D;
485  }
486  }
487 
488  DEBUG(dbgs() << "reuseValue is making the following changes\n");
489 
490  SmallVector<Instruction *, 4> InstsInPreheader;
491  for (int i = 0; i < Iterations; ++i) {
492  Instruction *InstInPreheader = Inst2Replace->clone();
494  for (int j = 0; j < NumOperands; ++j) {
495  Instruction *I = dyn_cast<Instruction>(Inst2Replace->getOperand(j));
496  if (!I)
497  continue;
498  // Get the DepChain corresponding to this operand.
499  DepChain &D = *DepChains[I];
500  // Get the PHI for the iteration number and find
501  // the incoming value from the Loop Preheader for
502  // that PHI.
503  Value *ValInPreheader = findValueInBlock(D[i], LoopPH);
504  InstInPreheader->setOperand(j, ValInPreheader);
505  }
506  InstsInPreheader.push_back(InstInPreheader);
507  InstInPreheader->setName(Inst2Replace->getName() + ".hexagon.vlcr");
508  InstInPreheader->insertBefore(LoopPH->getTerminator());
509  DEBUG(dbgs() << "Added " << *InstInPreheader << " to " << LoopPH->getName()
510  << "\n");
511  }
512  BasicBlock *BB = BEInst->getParent();
513  IRBuilder<> IRB(BB);
514  IRB.SetInsertPoint(BB->getFirstNonPHI());
515  Value *BEVal = BEInst;
516  PHINode *NewPhi;
517  for (int i = Iterations-1; i >=0 ; --i) {
518  Instruction *InstInPreheader = InstsInPreheader[i];
519  NewPhi = IRB.CreatePHI(InstInPreheader->getType(), 2);
520  NewPhi->addIncoming(InstInPreheader, LoopPH);
521  NewPhi->addIncoming(BEVal, BB);
522  DEBUG(dbgs() << "Adding " << *NewPhi << " to " << BB->getName() << "\n");
523  BEVal = NewPhi;
524  }
525  // We are in LCSSA form. So, a value defined inside the Loop is used only
526  // inside the loop. So, the following is safe.
527  Inst2Replace->replaceAllUsesWith(NewPhi);
528  ReplacedInsts.insert(Inst2Replace);
529  ++HexagonNumVectorLoopCarriedReuse;
530 }
531 
532 bool HexagonVectorLoopCarriedReuse::doVLCR() {
533  assert(CurLoop->getSubLoops().empty() &&
534  "Can do VLCR on the innermost loop only");
535  assert((CurLoop->getNumBlocks() == 1) &&
536  "Can do VLCR only on single block loops");
537 
538  bool Changed = false;
539  bool Continue;
540 
541  DEBUG(dbgs() << "Working on Loop: " << *CurLoop->getHeader() << "\n");
542  do {
543  // Reset datastructures.
544  Dependences.clear();
545  Continue = false;
546 
547  findLoopCarriedDeps();
548  findValueToReuse();
549  if (ReuseCandidate.isDefined()) {
550  reuseValue();
551  Changed = true;
552  Continue = true;
553  }
554  llvm::for_each(Dependences, std::default_delete<DepChain>());
555  } while (Continue);
556  return Changed;
557 }
558 
559 void HexagonVectorLoopCarriedReuse::findDepChainFromPHI(Instruction *I,
560  DepChain &D) {
561  PHINode *PN = dyn_cast<PHINode>(I);
562  if (!PN) {
563  D.push_back(I);
564  return;
565  } else {
566  auto NumIncomingValues = PN->getNumIncomingValues();
567  if (NumIncomingValues != 2) {
568  D.clear();
569  return;
570  }
571 
572  BasicBlock *BB = PN->getParent();
573  if (BB != CurLoop->getHeader()) {
574  D.clear();
575  return;
576  }
577 
578  Value *BEVal = PN->getIncomingValueForBlock(BB);
579  Instruction *BEInst = dyn_cast<Instruction>(BEVal);
580  // This is a single block loop with a preheader, so at least
581  // one value should come over the backedge.
582  assert(BEInst && "There should be a value over the backedge");
583 
584  Value *PreHdrVal =
585  PN->getIncomingValueForBlock(CurLoop->getLoopPreheader());
586  if(!PreHdrVal || !isa<Instruction>(PreHdrVal)) {
587  D.clear();
588  return;
589  }
590  D.push_back(PN);
591  findDepChainFromPHI(BEInst, D);
592  }
593 }
594 
595 bool HexagonVectorLoopCarriedReuse::isDepChainBtwn(Instruction *I1,
596  Instruction *I2,
597  int Iters) {
598  for (auto *D : Dependences) {
599  if (D->front() == I1 && D->back() == I2 && D->iterations() == Iters)
600  return true;
601  }
602  return false;
603 }
604 
605 DepChain *HexagonVectorLoopCarriedReuse::getDepChainBtwn(Instruction *I1,
606  Instruction *I2) {
607  for (auto *D : Dependences) {
608  if (D->front() == I1 && D->back() == I2)
609  return D;
610  }
611  return nullptr;
612 }
613 
614 void HexagonVectorLoopCarriedReuse::findLoopCarriedDeps() {
615  BasicBlock *BB = CurLoop->getHeader();
616  for (auto I = BB->begin(), E = BB->end(); I != E && isa<PHINode>(I); ++I) {
617  auto *PN = cast<PHINode>(I);
618  if (!isa<VectorType>(PN->getType()))
619  continue;
620 
621  DepChain *D = new DepChain();
622  findDepChainFromPHI(PN, *D);
623  if (D->size() != 0)
624  Dependences.insert(D);
625  else
626  delete D;
627  }
628  DEBUG(dbgs() << "Found " << Dependences.size() << " dependences\n");
629  DEBUG(for (size_t i = 0; i < Dependences.size(); ++i) {
630  dbgs() << *Dependences[i] << "\n";
631  });
632 }
633 
635  return new HexagonVectorLoopCarriedReuse();
636 }
Pass interface - Implemented by all &#39;passes&#39;.
Definition: Pass.h:81
use_iterator use_end()
Definition: Value.h:352
void addIncoming(Value *V, BasicBlock *BB)
Add an incoming value to the end of the PHI list.
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
bool isSameOperationAs(const Instruction *I, unsigned flags=0) const
This function determines if the specified instruction executes the same operation as the current one...
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:136
This class represents a function call, abstracting a target machine&#39;s calling convention.
static cl::opt< int > HexagonVLCRIterationLim("hexagon-vlcr-iteration-lim", cl::Hidden, cl::desc("Maximum distance of loop carried dependences that are handled"), cl::init(2), cl::ZeroOrMore)
STATISTIC(NumFunctions, "Total number of functions")
bool isVectorTy() const
True if this is an instance of VectorType.
Definition: Type.h:227
This defines the Use class.
iterator begin()
Instruction iterator methods.
Definition: BasicBlock.h:252
AnalysisUsage & addRequired()
#define INITIALIZE_PASS_DEPENDENCY(depName)
Definition: PassSupport.h:51
hexagon Hexagon specific predictive commoning for HVX vectors
A Use represents the edge between a Value definition and its users.
Definition: Use.h:56
INITIALIZE_PASS_BEGIN(HexagonVectorLoopCarriedReuse, "hexagon-vlcr", "Hexagon-specific predictive commoning for HVX vectors", false, false) INITIALIZE_PASS_END(HexagonVectorLoopCarriedReuse
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:668
void setName(const Twine &Name)
Change the name of the value.
Definition: Value.cpp:295
Instruction * clone() const
Create a copy of &#39;this&#39; instruction that is identical in all ways except the following: ...
User * getUser() const LLVM_READONLY
Returns the User that contains this Use.
Definition: Use.cpp:41
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
AnalysisUsage & addPreservedID(const void *ID)
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:439
void SetInsertPoint(BasicBlock *TheBB)
This specifies that created instructions should be appended to the end of the specified block...
Definition: IRBuilder.h:128
Value * getOperand(unsigned i) const
Definition: User.h:154
void initializeHexagonVectorLoopCarriedReusePass(PassRegistry &)
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:406
void insertBefore(Instruction *InsertPos)
Insert an unlinked instruction into a basic block immediately before the specified instruction...
Definition: Instruction.cpp:73
LLVM Basic Block Representation.
Definition: BasicBlock.h:59
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
Value * getIncomingValueForBlock(const BasicBlock *BB) const
char & LCSSAID
Definition: LCSSA.cpp:413
bool mayHaveSideEffects() const
Return true if the instruction may have side effects.
Definition: Instruction.h:536
Represent the analysis usage information of a pass.
#define LLVM_ATTRIBUTE_UNUSED
Definition: Compiler.h:144
INITIALIZE_PASS_END(RegBankSelect, DEBUG_TYPE, "Assign register bank of generic virtual registers", false, false) RegBankSelect
char & LoopSimplifyID
Intrinsic::ID getIntrinsicID() const
Return the intrinsic ID of this intrinsic.
Definition: IntrinsicInst.h:51
PHINode * CreatePHI(Type *Ty, unsigned NumReservedValues, const Twine &Name="")
Definition: IRBuilder.h:1658
unsigned getNumOperands() const
Definition: User.h:176
This is the shared class of boolean and integer constants.
Definition: Constants.h:84
iterator end()
Definition: BasicBlock.h:254
AnalysisUsage & addRequiredID(const void *ID)
Definition: Pass.cpp:298
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:862
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
void setPreservesCFG()
This function should be called by the pass, iff they do not:
Definition: Pass.cpp:285
unsigned getNumIncomingValues() const
Return the number of incoming edges.
void setOperand(unsigned i, Value *Val)
Definition: User.h:159
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:210
use_iterator use_begin()
Definition: Value.h:344
Pass * createHexagonVectorLoopCarriedReusePass()
Represents a single loop in the control flow graph.
Definition: LoopInfo.h:439
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:224
#define I(x, y, z)
Definition: MD5.cpp:58
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
raw_ostream & operator<<(raw_ostream &OS, const APInt &I)
Definition: APInt.h:2018
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
LLVM Value Representation.
Definition: Value.h:73
A vector that has set insertion semantics.
Definition: SetVector.h:41
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:44
#define DEBUG(X)
Definition: Debug.h:118
The legacy pass manager&#39;s analysis pass to compute loop information.
Definition: LoopInfo.h:958
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
PassRegistry - This class manages the registration and intitialization of the pass subsystem as appli...
Definition: PassRegistry.h:39
int64_t getSExtValue() const
Return the constant as a 64-bit integer value after it has been sign extended as appropriate for the ...
Definition: Constants.h:157
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
UnaryPredicate for_each(R &&Range, UnaryPredicate P)
Provide wrappers to std::for_each which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:807
for(unsigned i=Desc.getNumOperands(), e=OldMI.getNumOperands();i !=e;++i)
A wrapper class for inspecting calls to intrinsic functions.
Definition: IntrinsicInst.h:44
const BasicBlock * getParent() const
Definition: Instruction.h:67