LLVM  9.0.0svn
CodeExtractor.cpp
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1 //===- CodeExtractor.cpp - Pull code region into a new function -----------===//
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 the interface to tear out a code region, such as an
10 // individual loop or a parallel section, into a new function, replacing it with
11 // a call to the new function.
12 //
13 //===----------------------------------------------------------------------===//
14 
16 #include "llvm/ADT/ArrayRef.h"
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/Optional.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/SetVector.h"
21 #include "llvm/ADT/SmallPtrSet.h"
22 #include "llvm/ADT/SmallVector.h"
27 #include "llvm/Analysis/LoopInfo.h"
28 #include "llvm/IR/Argument.h"
29 #include "llvm/IR/Attributes.h"
30 #include "llvm/IR/BasicBlock.h"
31 #include "llvm/IR/CFG.h"
32 #include "llvm/IR/Constant.h"
33 #include "llvm/IR/Constants.h"
34 #include "llvm/IR/DataLayout.h"
35 #include "llvm/IR/DerivedTypes.h"
36 #include "llvm/IR/Dominators.h"
37 #include "llvm/IR/Function.h"
38 #include "llvm/IR/GlobalValue.h"
39 #include "llvm/IR/InstrTypes.h"
40 #include "llvm/IR/Instruction.h"
41 #include "llvm/IR/Instructions.h"
42 #include "llvm/IR/IntrinsicInst.h"
43 #include "llvm/IR/Intrinsics.h"
44 #include "llvm/IR/LLVMContext.h"
45 #include "llvm/IR/MDBuilder.h"
46 #include "llvm/IR/Module.h"
47 #include "llvm/IR/PatternMatch.h"
48 #include "llvm/IR/Type.h"
49 #include "llvm/IR/User.h"
50 #include "llvm/IR/Value.h"
51 #include "llvm/IR/Verifier.h"
52 #include "llvm/Pass.h"
55 #include "llvm/Support/Casting.h"
57 #include "llvm/Support/Debug.h"
62 #include <cassert>
63 #include <cstdint>
64 #include <iterator>
65 #include <map>
66 #include <set>
67 #include <utility>
68 #include <vector>
69 
70 using namespace llvm;
71 using namespace llvm::PatternMatch;
73 
74 #define DEBUG_TYPE "code-extractor"
75 
76 // Provide a command-line option to aggregate function arguments into a struct
77 // for functions produced by the code extractor. This is useful when converting
78 // extracted functions to pthread-based code, as only one argument (void*) can
79 // be passed in to pthread_create().
80 static cl::opt<bool>
81 AggregateArgsOpt("aggregate-extracted-args", cl::Hidden,
82  cl::desc("Aggregate arguments to code-extracted functions"));
83 
84 /// Test whether a block is valid for extraction.
85 static bool isBlockValidForExtraction(const BasicBlock &BB,
86  const SetVector<BasicBlock *> &Result,
87  bool AllowVarArgs, bool AllowAlloca) {
88  // taking the address of a basic block moved to another function is illegal
89  if (BB.hasAddressTaken())
90  return false;
91 
92  // don't hoist code that uses another basicblock address, as it's likely to
93  // lead to unexpected behavior, like cross-function jumps
96 
97  for (Instruction const &Inst : BB)
98  ToVisit.push_back(&Inst);
99 
100  while (!ToVisit.empty()) {
101  User const *Curr = ToVisit.pop_back_val();
102  if (!Visited.insert(Curr).second)
103  continue;
104  if (isa<BlockAddress const>(Curr))
105  return false; // even a reference to self is likely to be not compatible
106 
107  if (isa<Instruction>(Curr) && cast<Instruction>(Curr)->getParent() != &BB)
108  continue;
109 
110  for (auto const &U : Curr->operands()) {
111  if (auto *UU = dyn_cast<User>(U))
112  ToVisit.push_back(UU);
113  }
114  }
115 
116  // If explicitly requested, allow vastart and alloca. For invoke instructions
117  // verify that extraction is valid.
118  for (BasicBlock::const_iterator I = BB.begin(), E = BB.end(); I != E; ++I) {
119  if (isa<AllocaInst>(I)) {
120  if (!AllowAlloca)
121  return false;
122  continue;
123  }
124 
125  if (const auto *II = dyn_cast<InvokeInst>(I)) {
126  // Unwind destination (either a landingpad, catchswitch, or cleanuppad)
127  // must be a part of the subgraph which is being extracted.
128  if (auto *UBB = II->getUnwindDest())
129  if (!Result.count(UBB))
130  return false;
131  continue;
132  }
133 
134  // All catch handlers of a catchswitch instruction as well as the unwind
135  // destination must be in the subgraph.
136  if (const auto *CSI = dyn_cast<CatchSwitchInst>(I)) {
137  if (auto *UBB = CSI->getUnwindDest())
138  if (!Result.count(UBB))
139  return false;
140  for (auto *HBB : CSI->handlers())
141  if (!Result.count(const_cast<BasicBlock*>(HBB)))
142  return false;
143  continue;
144  }
145 
146  // Make sure that entire catch handler is within subgraph. It is sufficient
147  // to check that catch return's block is in the list.
148  if (const auto *CPI = dyn_cast<CatchPadInst>(I)) {
149  for (const auto *U : CPI->users())
150  if (const auto *CRI = dyn_cast<CatchReturnInst>(U))
151  if (!Result.count(const_cast<BasicBlock*>(CRI->getParent())))
152  return false;
153  continue;
154  }
155 
156  // And do similar checks for cleanup handler - the entire handler must be
157  // in subgraph which is going to be extracted. For cleanup return should
158  // additionally check that the unwind destination is also in the subgraph.
159  if (const auto *CPI = dyn_cast<CleanupPadInst>(I)) {
160  for (const auto *U : CPI->users())
161  if (const auto *CRI = dyn_cast<CleanupReturnInst>(U))
162  if (!Result.count(const_cast<BasicBlock*>(CRI->getParent())))
163  return false;
164  continue;
165  }
166  if (const auto *CRI = dyn_cast<CleanupReturnInst>(I)) {
167  if (auto *UBB = CRI->getUnwindDest())
168  if (!Result.count(UBB))
169  return false;
170  continue;
171  }
172 
173  if (const CallInst *CI = dyn_cast<CallInst>(I)) {
174  if (const Function *F = CI->getCalledFunction()) {
175  auto IID = F->getIntrinsicID();
176  if (IID == Intrinsic::vastart) {
177  if (AllowVarArgs)
178  continue;
179  else
180  return false;
181  }
182 
183  // Currently, we miscompile outlined copies of eh_typid_for. There are
184  // proposals for fixing this in llvm.org/PR39545.
185  if (IID == Intrinsic::eh_typeid_for)
186  return false;
187  }
188  }
189  }
190 
191  return true;
192 }
193 
194 /// Build a set of blocks to extract if the input blocks are viable.
197  bool AllowVarArgs, bool AllowAlloca) {
198  assert(!BBs.empty() && "The set of blocks to extract must be non-empty");
200 
201  // Loop over the blocks, adding them to our set-vector, and aborting with an
202  // empty set if we encounter invalid blocks.
203  for (BasicBlock *BB : BBs) {
204  // If this block is dead, don't process it.
205  if (DT && !DT->isReachableFromEntry(BB))
206  continue;
207 
208  if (!Result.insert(BB))
209  llvm_unreachable("Repeated basic blocks in extraction input");
210  }
211 
212  for (auto *BB : Result) {
213  if (!isBlockValidForExtraction(*BB, Result, AllowVarArgs, AllowAlloca))
214  return {};
215 
216  // Make sure that the first block is not a landing pad.
217  if (BB == Result.front()) {
218  if (BB->isEHPad()) {
219  LLVM_DEBUG(dbgs() << "The first block cannot be an unwind block\n");
220  return {};
221  }
222  continue;
223  }
224 
225  // All blocks other than the first must not have predecessors outside of
226  // the subgraph which is being extracted.
227  for (auto *PBB : predecessors(BB))
228  if (!Result.count(PBB)) {
229  LLVM_DEBUG(
230  dbgs() << "No blocks in this region may have entries from "
231  "outside the region except for the first block!\n");
232  return {};
233  }
234  }
235 
236  return Result;
237 }
238 
240  bool AggregateArgs, BlockFrequencyInfo *BFI,
242  bool AllowVarArgs, bool AllowAlloca,
243  std::string Suffix)
244  : DT(DT), AggregateArgs(AggregateArgs || AggregateArgsOpt), BFI(BFI),
245  BPI(BPI), AC(AC), AllowVarArgs(AllowVarArgs),
246  Blocks(buildExtractionBlockSet(BBs, DT, AllowVarArgs, AllowAlloca)),
247  Suffix(Suffix) {}
248 
249 CodeExtractor::CodeExtractor(DominatorTree &DT, Loop &L, bool AggregateArgs,
250  BlockFrequencyInfo *BFI,
252  std::string Suffix)
253  : DT(&DT), AggregateArgs(AggregateArgs || AggregateArgsOpt), BFI(BFI),
254  BPI(BPI), AC(AC), AllowVarArgs(false),
255  Blocks(buildExtractionBlockSet(L.getBlocks(), &DT,
256  /* AllowVarArgs */ false,
257  /* AllowAlloca */ false)),
258  Suffix(Suffix) {}
259 
260 /// definedInRegion - Return true if the specified value is defined in the
261 /// extracted region.
262 static bool definedInRegion(const SetVector<BasicBlock *> &Blocks, Value *V) {
263  if (Instruction *I = dyn_cast<Instruction>(V))
264  if (Blocks.count(I->getParent()))
265  return true;
266  return false;
267 }
268 
269 /// definedInCaller - Return true if the specified value is defined in the
270 /// function being code extracted, but not in the region being extracted.
271 /// These values must be passed in as live-ins to the function.
272 static bool definedInCaller(const SetVector<BasicBlock *> &Blocks, Value *V) {
273  if (isa<Argument>(V)) return true;
274  if (Instruction *I = dyn_cast<Instruction>(V))
275  if (!Blocks.count(I->getParent()))
276  return true;
277  return false;
278 }
279 
281  BasicBlock *CommonExitBlock = nullptr;
282  auto hasNonCommonExitSucc = [&](BasicBlock *Block) {
283  for (auto *Succ : successors(Block)) {
284  // Internal edges, ok.
285  if (Blocks.count(Succ))
286  continue;
287  if (!CommonExitBlock) {
288  CommonExitBlock = Succ;
289  continue;
290  }
291  if (CommonExitBlock == Succ)
292  continue;
293 
294  return true;
295  }
296  return false;
297  };
298 
299  if (any_of(Blocks, hasNonCommonExitSucc))
300  return nullptr;
301 
302  return CommonExitBlock;
303 }
304 
306  Instruction *Addr) const {
307  AllocaInst *AI = cast<AllocaInst>(Addr->stripInBoundsConstantOffsets());
308  Function *Func = (*Blocks.begin())->getParent();
309  for (BasicBlock &BB : *Func) {
310  if (Blocks.count(&BB))
311  continue;
312  for (Instruction &II : BB) {
313  if (isa<DbgInfoIntrinsic>(II))
314  continue;
315 
316  unsigned Opcode = II.getOpcode();
317  Value *MemAddr = nullptr;
318  switch (Opcode) {
319  case Instruction::Store:
320  case Instruction::Load: {
321  if (Opcode == Instruction::Store) {
322  StoreInst *SI = cast<StoreInst>(&II);
323  MemAddr = SI->getPointerOperand();
324  } else {
325  LoadInst *LI = cast<LoadInst>(&II);
326  MemAddr = LI->getPointerOperand();
327  }
328  // Global variable can not be aliased with locals.
329  if (dyn_cast<Constant>(MemAddr))
330  break;
332  if (!dyn_cast<AllocaInst>(Base) || Base == AI)
333  return false;
334  break;
335  }
336  default: {
337  IntrinsicInst *IntrInst = dyn_cast<IntrinsicInst>(&II);
338  if (IntrInst) {
339  if (IntrInst->isLifetimeStartOrEnd())
340  break;
341  return false;
342  }
343  // Treat all the other cases conservatively if it has side effects.
344  if (II.mayHaveSideEffects())
345  return false;
346  }
347  }
348  }
349  }
350 
351  return true;
352 }
353 
354 BasicBlock *
356  BasicBlock *SinglePredFromOutlineRegion = nullptr;
357  assert(!Blocks.count(CommonExitBlock) &&
358  "Expect a block outside the region!");
359  for (auto *Pred : predecessors(CommonExitBlock)) {
360  if (!Blocks.count(Pred))
361  continue;
362  if (!SinglePredFromOutlineRegion) {
363  SinglePredFromOutlineRegion = Pred;
364  } else if (SinglePredFromOutlineRegion != Pred) {
365  SinglePredFromOutlineRegion = nullptr;
366  break;
367  }
368  }
369 
370  if (SinglePredFromOutlineRegion)
371  return SinglePredFromOutlineRegion;
372 
373 #ifndef NDEBUG
374  auto getFirstPHI = [](BasicBlock *BB) {
375  BasicBlock::iterator I = BB->begin();
376  PHINode *FirstPhi = nullptr;
377  while (I != BB->end()) {
378  PHINode *Phi = dyn_cast<PHINode>(I);
379  if (!Phi)
380  break;
381  if (!FirstPhi) {
382  FirstPhi = Phi;
383  break;
384  }
385  }
386  return FirstPhi;
387  };
388  // If there are any phi nodes, the single pred either exists or has already
389  // be created before code extraction.
390  assert(!getFirstPHI(CommonExitBlock) && "Phi not expected");
391 #endif
392 
393  BasicBlock *NewExitBlock = CommonExitBlock->splitBasicBlock(
394  CommonExitBlock->getFirstNonPHI()->getIterator());
395 
396  for (auto PI = pred_begin(CommonExitBlock), PE = pred_end(CommonExitBlock);
397  PI != PE;) {
398  BasicBlock *Pred = *PI++;
399  if (Blocks.count(Pred))
400  continue;
401  Pred->getTerminator()->replaceUsesOfWith(CommonExitBlock, NewExitBlock);
402  }
403  // Now add the old exit block to the outline region.
404  Blocks.insert(CommonExitBlock);
405  return CommonExitBlock;
406 }
407 
408 void CodeExtractor::findAllocas(ValueSet &SinkCands, ValueSet &HoistCands,
409  BasicBlock *&ExitBlock) const {
410  Function *Func = (*Blocks.begin())->getParent();
411  ExitBlock = getCommonExitBlock(Blocks);
412 
413  for (BasicBlock &BB : *Func) {
414  if (Blocks.count(&BB))
415  continue;
416  for (Instruction &II : BB) {
417  auto *AI = dyn_cast<AllocaInst>(&II);
418  if (!AI)
419  continue;
420 
421  // Find the pair of life time markers for address 'Addr' that are either
422  // defined inside the outline region or can legally be shrinkwrapped into
423  // the outline region. If there are not other untracked uses of the
424  // address, return the pair of markers if found; otherwise return a pair
425  // of nullptr.
426  auto GetLifeTimeMarkers =
427  [&](Instruction *Addr, bool &SinkLifeStart,
428  bool &HoistLifeEnd) -> std::pair<Instruction *, Instruction *> {
429  Instruction *LifeStart = nullptr, *LifeEnd = nullptr;
430 
431  for (User *U : Addr->users()) {
432  IntrinsicInst *IntrInst = dyn_cast<IntrinsicInst>(U);
433  if (IntrInst) {
434  if (IntrInst->getIntrinsicID() == Intrinsic::lifetime_start) {
435  // Do not handle the case where AI has multiple start markers.
436  if (LifeStart)
437  return std::make_pair<Instruction *>(nullptr, nullptr);
438  LifeStart = IntrInst;
439  }
440  if (IntrInst->getIntrinsicID() == Intrinsic::lifetime_end) {
441  if (LifeEnd)
442  return std::make_pair<Instruction *>(nullptr, nullptr);
443  LifeEnd = IntrInst;
444  }
445  continue;
446  }
447  // Find untracked uses of the address, bail.
448  if (!definedInRegion(Blocks, U))
449  return std::make_pair<Instruction *>(nullptr, nullptr);
450  }
451 
452  if (!LifeStart || !LifeEnd)
453  return std::make_pair<Instruction *>(nullptr, nullptr);
454 
455  SinkLifeStart = !definedInRegion(Blocks, LifeStart);
456  HoistLifeEnd = !definedInRegion(Blocks, LifeEnd);
457  // Do legality Check.
458  if ((SinkLifeStart || HoistLifeEnd) &&
460  return std::make_pair<Instruction *>(nullptr, nullptr);
461 
462  // Check to see if we have a place to do hoisting, if not, bail.
463  if (HoistLifeEnd && !ExitBlock)
464  return std::make_pair<Instruction *>(nullptr, nullptr);
465 
466  return std::make_pair(LifeStart, LifeEnd);
467  };
468 
469  bool SinkLifeStart = false, HoistLifeEnd = false;
470  auto Markers = GetLifeTimeMarkers(AI, SinkLifeStart, HoistLifeEnd);
471 
472  if (Markers.first) {
473  if (SinkLifeStart)
474  SinkCands.insert(Markers.first);
475  SinkCands.insert(AI);
476  if (HoistLifeEnd)
477  HoistCands.insert(Markers.second);
478  continue;
479  }
480 
481  // Follow the bitcast.
482  Instruction *MarkerAddr = nullptr;
483  for (User *U : AI->users()) {
484  if (U->stripInBoundsConstantOffsets() == AI) {
485  SinkLifeStart = false;
486  HoistLifeEnd = false;
487  Instruction *Bitcast = cast<Instruction>(U);
488  Markers = GetLifeTimeMarkers(Bitcast, SinkLifeStart, HoistLifeEnd);
489  if (Markers.first) {
490  MarkerAddr = Bitcast;
491  continue;
492  }
493  }
494 
495  // Found unknown use of AI.
496  if (!definedInRegion(Blocks, U)) {
497  MarkerAddr = nullptr;
498  break;
499  }
500  }
501 
502  if (MarkerAddr) {
503  if (SinkLifeStart)
504  SinkCands.insert(Markers.first);
505  if (!definedInRegion(Blocks, MarkerAddr))
506  SinkCands.insert(MarkerAddr);
507  SinkCands.insert(AI);
508  if (HoistLifeEnd)
509  HoistCands.insert(Markers.second);
510  }
511  }
512  }
513 }
514 
516  const ValueSet &SinkCands) const {
517  for (BasicBlock *BB : Blocks) {
518  // If a used value is defined outside the region, it's an input. If an
519  // instruction is used outside the region, it's an output.
520  for (Instruction &II : *BB) {
521  for (User::op_iterator OI = II.op_begin(), OE = II.op_end(); OI != OE;
522  ++OI) {
523  Value *V = *OI;
524  if (!SinkCands.count(V) && definedInCaller(Blocks, V))
525  Inputs.insert(V);
526  }
527 
528  for (User *U : II.users())
529  if (!definedInRegion(Blocks, U)) {
530  Outputs.insert(&II);
531  break;
532  }
533  }
534  }
535 }
536 
537 /// severSplitPHINodesOfEntry - If a PHI node has multiple inputs from outside
538 /// of the region, we need to split the entry block of the region so that the
539 /// PHI node is easier to deal with.
540 void CodeExtractor::severSplitPHINodesOfEntry(BasicBlock *&Header) {
541  unsigned NumPredsFromRegion = 0;
542  unsigned NumPredsOutsideRegion = 0;
543 
544  if (Header != &Header->getParent()->getEntryBlock()) {
545  PHINode *PN = dyn_cast<PHINode>(Header->begin());
546  if (!PN) return; // No PHI nodes.
547 
548  // If the header node contains any PHI nodes, check to see if there is more
549  // than one entry from outside the region. If so, we need to sever the
550  // header block into two.
551  for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
552  if (Blocks.count(PN->getIncomingBlock(i)))
553  ++NumPredsFromRegion;
554  else
555  ++NumPredsOutsideRegion;
556 
557  // If there is one (or fewer) predecessor from outside the region, we don't
558  // need to do anything special.
559  if (NumPredsOutsideRegion <= 1) return;
560  }
561 
562  // Otherwise, we need to split the header block into two pieces: one
563  // containing PHI nodes merging values from outside of the region, and a
564  // second that contains all of the code for the block and merges back any
565  // incoming values from inside of the region.
566  BasicBlock *NewBB = SplitBlock(Header, Header->getFirstNonPHI(), DT);
567 
568  // We only want to code extract the second block now, and it becomes the new
569  // header of the region.
570  BasicBlock *OldPred = Header;
571  Blocks.remove(OldPred);
572  Blocks.insert(NewBB);
573  Header = NewBB;
574 
575  // Okay, now we need to adjust the PHI nodes and any branches from within the
576  // region to go to the new header block instead of the old header block.
577  if (NumPredsFromRegion) {
578  PHINode *PN = cast<PHINode>(OldPred->begin());
579  // Loop over all of the predecessors of OldPred that are in the region,
580  // changing them to branch to NewBB instead.
581  for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
582  if (Blocks.count(PN->getIncomingBlock(i))) {
584  TI->replaceUsesOfWith(OldPred, NewBB);
585  }
586 
587  // Okay, everything within the region is now branching to the right block, we
588  // just have to update the PHI nodes now, inserting PHI nodes into NewBB.
589  BasicBlock::iterator AfterPHIs;
590  for (AfterPHIs = OldPred->begin(); isa<PHINode>(AfterPHIs); ++AfterPHIs) {
591  PHINode *PN = cast<PHINode>(AfterPHIs);
592  // Create a new PHI node in the new region, which has an incoming value
593  // from OldPred of PN.
594  PHINode *NewPN = PHINode::Create(PN->getType(), 1 + NumPredsFromRegion,
595  PN->getName() + ".ce", &NewBB->front());
596  PN->replaceAllUsesWith(NewPN);
597  NewPN->addIncoming(PN, OldPred);
598 
599  // Loop over all of the incoming value in PN, moving them to NewPN if they
600  // are from the extracted region.
601  for (unsigned i = 0; i != PN->getNumIncomingValues(); ++i) {
602  if (Blocks.count(PN->getIncomingBlock(i))) {
603  NewPN->addIncoming(PN->getIncomingValue(i), PN->getIncomingBlock(i));
604  PN->removeIncomingValue(i);
605  --i;
606  }
607  }
608  }
609  }
610 }
611 
612 /// severSplitPHINodesOfExits - if PHI nodes in exit blocks have inputs from
613 /// outlined region, we split these PHIs on two: one with inputs from region
614 /// and other with remaining incoming blocks; then first PHIs are placed in
615 /// outlined region.
616 void CodeExtractor::severSplitPHINodesOfExits(
617  const SmallPtrSetImpl<BasicBlock *> &Exits) {
618  for (BasicBlock *ExitBB : Exits) {
619  BasicBlock *NewBB = nullptr;
620 
621  for (PHINode &PN : ExitBB->phis()) {
622  // Find all incoming values from the outlining region.
623  SmallVector<unsigned, 2> IncomingVals;
624  for (unsigned i = 0; i < PN.getNumIncomingValues(); ++i)
625  if (Blocks.count(PN.getIncomingBlock(i)))
626  IncomingVals.push_back(i);
627 
628  // Do not process PHI if there is one (or fewer) predecessor from region.
629  // If PHI has exactly one predecessor from region, only this one incoming
630  // will be replaced on codeRepl block, so it should be safe to skip PHI.
631  if (IncomingVals.size() <= 1)
632  continue;
633 
634  // Create block for new PHIs and add it to the list of outlined if it
635  // wasn't done before.
636  if (!NewBB) {
637  NewBB = BasicBlock::Create(ExitBB->getContext(),
638  ExitBB->getName() + ".split",
639  ExitBB->getParent(), ExitBB);
641  pred_end(ExitBB));
642  for (BasicBlock *PredBB : Preds)
643  if (Blocks.count(PredBB))
644  PredBB->getTerminator()->replaceUsesOfWith(ExitBB, NewBB);
645  BranchInst::Create(ExitBB, NewBB);
646  Blocks.insert(NewBB);
647  }
648 
649  // Split this PHI.
650  PHINode *NewPN =
651  PHINode::Create(PN.getType(), IncomingVals.size(),
652  PN.getName() + ".ce", NewBB->getFirstNonPHI());
653  for (unsigned i : IncomingVals)
654  NewPN->addIncoming(PN.getIncomingValue(i), PN.getIncomingBlock(i));
655  for (unsigned i : reverse(IncomingVals))
656  PN.removeIncomingValue(i, false);
657  PN.addIncoming(NewPN, NewBB);
658  }
659  }
660 }
661 
662 void CodeExtractor::splitReturnBlocks() {
663  for (BasicBlock *Block : Blocks)
664  if (ReturnInst *RI = dyn_cast<ReturnInst>(Block->getTerminator())) {
665  BasicBlock *New =
666  Block->splitBasicBlock(RI->getIterator(), Block->getName() + ".ret");
667  if (DT) {
668  // Old dominates New. New node dominates all other nodes dominated
669  // by Old.
670  DomTreeNode *OldNode = DT->getNode(Block);
671  SmallVector<DomTreeNode *, 8> Children(OldNode->begin(),
672  OldNode->end());
673 
674  DomTreeNode *NewNode = DT->addNewBlock(New, Block);
675 
676  for (DomTreeNode *I : Children)
677  DT->changeImmediateDominator(I, NewNode);
678  }
679  }
680 }
681 
682 /// constructFunction - make a function based on inputs and outputs, as follows:
683 /// f(in0, ..., inN, out0, ..., outN)
684 Function *CodeExtractor::constructFunction(const ValueSet &inputs,
685  const ValueSet &outputs,
686  BasicBlock *header,
687  BasicBlock *newRootNode,
688  BasicBlock *newHeader,
689  Function *oldFunction,
690  Module *M) {
691  LLVM_DEBUG(dbgs() << "inputs: " << inputs.size() << "\n");
692  LLVM_DEBUG(dbgs() << "outputs: " << outputs.size() << "\n");
693 
694  // This function returns unsigned, outputs will go back by reference.
695  switch (NumExitBlocks) {
696  case 0:
697  case 1: RetTy = Type::getVoidTy(header->getContext()); break;
698  case 2: RetTy = Type::getInt1Ty(header->getContext()); break;
699  default: RetTy = Type::getInt16Ty(header->getContext()); break;
700  }
701 
702  std::vector<Type *> paramTy;
703 
704  // Add the types of the input values to the function's argument list
705  for (Value *value : inputs) {
706  LLVM_DEBUG(dbgs() << "value used in func: " << *value << "\n");
707  paramTy.push_back(value->getType());
708  }
709 
710  // Add the types of the output values to the function's argument list.
711  for (Value *output : outputs) {
712  LLVM_DEBUG(dbgs() << "instr used in func: " << *output << "\n");
713  if (AggregateArgs)
714  paramTy.push_back(output->getType());
715  else
716  paramTy.push_back(PointerType::getUnqual(output->getType()));
717  }
718 
719  LLVM_DEBUG({
720  dbgs() << "Function type: " << *RetTy << " f(";
721  for (Type *i : paramTy)
722  dbgs() << *i << ", ";
723  dbgs() << ")\n";
724  });
725 
726  StructType *StructTy;
727  if (AggregateArgs && (inputs.size() + outputs.size() > 0)) {
728  StructTy = StructType::get(M->getContext(), paramTy);
729  paramTy.clear();
730  paramTy.push_back(PointerType::getUnqual(StructTy));
731  }
732  FunctionType *funcType =
733  FunctionType::get(RetTy, paramTy,
734  AllowVarArgs && oldFunction->isVarArg());
735 
736  std::string SuffixToUse =
737  Suffix.empty()
738  ? (header->getName().empty() ? "extracted" : header->getName().str())
739  : Suffix;
740  // Create the new function
741  Function *newFunction = Function::Create(
742  funcType, GlobalValue::InternalLinkage, oldFunction->getAddressSpace(),
743  oldFunction->getName() + "." + SuffixToUse, M);
744  // If the old function is no-throw, so is the new one.
745  if (oldFunction->doesNotThrow())
746  newFunction->setDoesNotThrow();
747 
748  // Inherit the uwtable attribute if we need to.
749  if (oldFunction->hasUWTable())
750  newFunction->setHasUWTable();
751 
752  // Inherit all of the target dependent attributes and white-listed
753  // target independent attributes.
754  // (e.g. If the extracted region contains a call to an x86.sse
755  // instruction we need to make sure that the extracted region has the
756  // "target-features" attribute allowing it to be lowered.
757  // FIXME: This should be changed to check to see if a specific
758  // attribute can not be inherited.
759  for (const auto &Attr : oldFunction->getAttributes().getFnAttributes()) {
760  if (Attr.isStringAttribute()) {
761  if (Attr.getKindAsString() == "thunk")
762  continue;
763  } else
764  switch (Attr.getKindAsEnum()) {
765  // Those attributes cannot be propagated safely. Explicitly list them
766  // here so we get a warning if new attributes are added. This list also
767  // includes non-function attributes.
768  case Attribute::Alignment:
769  case Attribute::AllocSize:
770  case Attribute::ArgMemOnly:
771  case Attribute::Builtin:
772  case Attribute::ByVal:
774  case Attribute::Dereferenceable:
775  case Attribute::DereferenceableOrNull:
776  case Attribute::InAlloca:
777  case Attribute::InReg:
778  case Attribute::InaccessibleMemOnly:
779  case Attribute::InaccessibleMemOrArgMemOnly:
781  case Attribute::Naked:
782  case Attribute::Nest:
783  case Attribute::NoAlias:
784  case Attribute::NoBuiltin:
785  case Attribute::NoCapture:
786  case Attribute::NoReturn:
787  case Attribute::None:
788  case Attribute::NonNull:
789  case Attribute::ReadNone:
790  case Attribute::ReadOnly:
791  case Attribute::Returned:
792  case Attribute::ReturnsTwice:
793  case Attribute::SExt:
794  case Attribute::Speculatable:
795  case Attribute::StackAlignment:
796  case Attribute::StructRet:
797  case Attribute::SwiftError:
798  case Attribute::SwiftSelf:
799  case Attribute::WriteOnly:
800  case Attribute::ZExt:
802  continue;
803  // Those attributes should be safe to propagate to the extracted function.
804  case Attribute::AlwaysInline:
805  case Attribute::Cold:
806  case Attribute::NoRecurse:
807  case Attribute::InlineHint:
808  case Attribute::MinSize:
809  case Attribute::NoDuplicate:
810  case Attribute::NoImplicitFloat:
811  case Attribute::NoInline:
812  case Attribute::NonLazyBind:
813  case Attribute::NoRedZone:
814  case Attribute::NoUnwind:
815  case Attribute::OptForFuzzing:
816  case Attribute::OptimizeNone:
817  case Attribute::OptimizeForSize:
818  case Attribute::SafeStack:
819  case Attribute::ShadowCallStack:
820  case Attribute::SanitizeAddress:
821  case Attribute::SanitizeMemory:
822  case Attribute::SanitizeThread:
823  case Attribute::SanitizeHWAddress:
824  case Attribute::SpeculativeLoadHardening:
825  case Attribute::StackProtect:
826  case Attribute::StackProtectReq:
827  case Attribute::StackProtectStrong:
828  case Attribute::StrictFP:
829  case Attribute::UWTable:
830  case Attribute::NoCfCheck:
831  break;
832  }
833 
834  newFunction->addFnAttr(Attr);
835  }
836  newFunction->getBasicBlockList().push_back(newRootNode);
837 
838  // Create an iterator to name all of the arguments we inserted.
839  Function::arg_iterator AI = newFunction->arg_begin();
840 
841  // Rewrite all users of the inputs in the extracted region to use the
842  // arguments (or appropriate addressing into struct) instead.
843  for (unsigned i = 0, e = inputs.size(); i != e; ++i) {
844  Value *RewriteVal;
845  if (AggregateArgs) {
846  Value *Idx[2];
848  Idx[1] = ConstantInt::get(Type::getInt32Ty(header->getContext()), i);
849  Instruction *TI = newFunction->begin()->getTerminator();
851  StructTy, &*AI, Idx, "gep_" + inputs[i]->getName(), TI);
852  RewriteVal = new LoadInst(StructTy->getElementType(i), GEP,
853  "loadgep_" + inputs[i]->getName(), TI);
854  } else
855  RewriteVal = &*AI++;
856 
857  std::vector<User *> Users(inputs[i]->user_begin(), inputs[i]->user_end());
858  for (User *use : Users)
859  if (Instruction *inst = dyn_cast<Instruction>(use))
860  if (Blocks.count(inst->getParent()))
861  inst->replaceUsesOfWith(inputs[i], RewriteVal);
862  }
863 
864  // Set names for input and output arguments.
865  if (!AggregateArgs) {
866  AI = newFunction->arg_begin();
867  for (unsigned i = 0, e = inputs.size(); i != e; ++i, ++AI)
868  AI->setName(inputs[i]->getName());
869  for (unsigned i = 0, e = outputs.size(); i != e; ++i, ++AI)
870  AI->setName(outputs[i]->getName()+".out");
871  }
872 
873  // Rewrite branches to basic blocks outside of the loop to new dummy blocks
874  // within the new function. This must be done before we lose track of which
875  // blocks were originally in the code region.
876  std::vector<User *> Users(header->user_begin(), header->user_end());
877  for (unsigned i = 0, e = Users.size(); i != e; ++i)
878  // The BasicBlock which contains the branch is not in the region
879  // modify the branch target to a new block
880  if (Instruction *I = dyn_cast<Instruction>(Users[i]))
881  if (I->isTerminator() && !Blocks.count(I->getParent()) &&
882  I->getParent()->getParent() == oldFunction)
883  I->replaceUsesOfWith(header, newHeader);
884 
885  return newFunction;
886 }
887 
888 /// Erase lifetime.start markers which reference inputs to the extraction
889 /// region, and insert the referenced memory into \p LifetimesStart.
890 ///
891 /// The extraction region is defined by a set of blocks (\p Blocks), and a set
892 /// of allocas which will be moved from the caller function into the extracted
893 /// function (\p SunkAllocas).
895  const SetVector<Value *> &SunkAllocas,
896  SetVector<Value *> &LifetimesStart) {
897  for (BasicBlock *BB : Blocks) {
898  for (auto It = BB->begin(), End = BB->end(); It != End;) {
899  auto *II = dyn_cast<IntrinsicInst>(&*It);
900  ++It;
901  if (!II || !II->isLifetimeStartOrEnd())
902  continue;
903 
904  // Get the memory operand of the lifetime marker. If the underlying
905  // object is a sunk alloca, or is otherwise defined in the extraction
906  // region, the lifetime marker must not be erased.
907  Value *Mem = II->getOperand(1)->stripInBoundsOffsets();
908  if (SunkAllocas.count(Mem) || definedInRegion(Blocks, Mem))
909  continue;
910 
911  if (II->getIntrinsicID() == Intrinsic::lifetime_start)
912  LifetimesStart.insert(Mem);
913  II->eraseFromParent();
914  }
915  }
916 }
917 
918 /// Insert lifetime start/end markers surrounding the call to the new function
919 /// for objects defined in the caller.
921  Module *M, ArrayRef<Value *> LifetimesStart, ArrayRef<Value *> LifetimesEnd,
922  CallInst *TheCall) {
923  LLVMContext &Ctx = M->getContext();
924  auto Int8PtrTy = Type::getInt8PtrTy(Ctx);
925  auto NegativeOne = ConstantInt::getSigned(Type::getInt64Ty(Ctx), -1);
926  Instruction *Term = TheCall->getParent()->getTerminator();
927 
928  // The memory argument to a lifetime marker must be a i8*. Cache any bitcasts
929  // needed to satisfy this requirement so they may be reused.
931 
932  // Emit lifetime markers for the pointers given in \p Objects. Insert the
933  // markers before the call if \p InsertBefore, and after the call otherwise.
934  auto insertMarkers = [&](Function *MarkerFunc, ArrayRef<Value *> Objects,
935  bool InsertBefore) {
936  for (Value *Mem : Objects) {
937  assert((!isa<Instruction>(Mem) || cast<Instruction>(Mem)->getFunction() ==
938  TheCall->getFunction()) &&
939  "Input memory not defined in original function");
940  Value *&MemAsI8Ptr = Bitcasts[Mem];
941  if (!MemAsI8Ptr) {
942  if (Mem->getType() == Int8PtrTy)
943  MemAsI8Ptr = Mem;
944  else
945  MemAsI8Ptr =
946  CastInst::CreatePointerCast(Mem, Int8PtrTy, "lt.cast", TheCall);
947  }
948 
949  auto Marker = CallInst::Create(MarkerFunc, {NegativeOne, MemAsI8Ptr});
950  if (InsertBefore)
951  Marker->insertBefore(TheCall);
952  else
953  Marker->insertBefore(Term);
954  }
955  };
956 
957  if (!LifetimesStart.empty()) {
958  auto StartFn = llvm::Intrinsic::getDeclaration(
959  M, llvm::Intrinsic::lifetime_start, Int8PtrTy);
960  insertMarkers(StartFn, LifetimesStart, /*InsertBefore=*/true);
961  }
962 
963  if (!LifetimesEnd.empty()) {
964  auto EndFn = llvm::Intrinsic::getDeclaration(
965  M, llvm::Intrinsic::lifetime_end, Int8PtrTy);
966  insertMarkers(EndFn, LifetimesEnd, /*InsertBefore=*/false);
967  }
968 }
969 
970 /// emitCallAndSwitchStatement - This method sets up the caller side by adding
971 /// the call instruction, splitting any PHI nodes in the header block as
972 /// necessary.
973 CallInst *CodeExtractor::emitCallAndSwitchStatement(Function *newFunction,
974  BasicBlock *codeReplacer,
975  ValueSet &inputs,
976  ValueSet &outputs) {
977  // Emit a call to the new function, passing in: *pointer to struct (if
978  // aggregating parameters), or plan inputs and allocated memory for outputs
979  std::vector<Value *> params, StructValues, ReloadOutputs, Reloads;
980 
981  Module *M = newFunction->getParent();
983  const DataLayout &DL = M->getDataLayout();
984  CallInst *call = nullptr;
985 
986  // Add inputs as params, or to be filled into the struct
987  unsigned ArgNo = 0;
988  SmallVector<unsigned, 1> SwiftErrorArgs;
989  for (Value *input : inputs) {
990  if (AggregateArgs)
991  StructValues.push_back(input);
992  else {
993  params.push_back(input);
994  if (input->isSwiftError())
995  SwiftErrorArgs.push_back(ArgNo);
996  }
997  ++ArgNo;
998  }
999 
1000  // Create allocas for the outputs
1001  for (Value *output : outputs) {
1002  if (AggregateArgs) {
1003  StructValues.push_back(output);
1004  } else {
1005  AllocaInst *alloca =
1006  new AllocaInst(output->getType(), DL.getAllocaAddrSpace(),
1007  nullptr, output->getName() + ".loc",
1008  &codeReplacer->getParent()->front().front());
1009  ReloadOutputs.push_back(alloca);
1010  params.push_back(alloca);
1011  }
1012  }
1013 
1014  StructType *StructArgTy = nullptr;
1015  AllocaInst *Struct = nullptr;
1016  if (AggregateArgs && (inputs.size() + outputs.size() > 0)) {
1017  std::vector<Type *> ArgTypes;
1018  for (ValueSet::iterator v = StructValues.begin(),
1019  ve = StructValues.end(); v != ve; ++v)
1020  ArgTypes.push_back((*v)->getType());
1021 
1022  // Allocate a struct at the beginning of this function
1023  StructArgTy = StructType::get(newFunction->getContext(), ArgTypes);
1024  Struct = new AllocaInst(StructArgTy, DL.getAllocaAddrSpace(), nullptr,
1025  "structArg",
1026  &codeReplacer->getParent()->front().front());
1027  params.push_back(Struct);
1028 
1029  for (unsigned i = 0, e = inputs.size(); i != e; ++i) {
1030  Value *Idx[2];
1031  Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
1032  Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), i);
1034  StructArgTy, Struct, Idx, "gep_" + StructValues[i]->getName());
1035  codeReplacer->getInstList().push_back(GEP);
1036  StoreInst *SI = new StoreInst(StructValues[i], GEP);
1037  codeReplacer->getInstList().push_back(SI);
1038  }
1039  }
1040 
1041  // Emit the call to the function
1042  call = CallInst::Create(newFunction, params,
1043  NumExitBlocks > 1 ? "targetBlock" : "");
1044  // Add debug location to the new call, if the original function has debug
1045  // info. In that case, the terminator of the entry block of the extracted
1046  // function contains the first debug location of the extracted function,
1047  // set in extractCodeRegion.
1048  if (codeReplacer->getParent()->getSubprogram()) {
1049  if (auto DL = newFunction->getEntryBlock().getTerminator()->getDebugLoc())
1050  call->setDebugLoc(DL);
1051  }
1052  codeReplacer->getInstList().push_back(call);
1053 
1054  // Set swifterror parameter attributes.
1055  for (unsigned SwiftErrArgNo : SwiftErrorArgs) {
1056  call->addParamAttr(SwiftErrArgNo, Attribute::SwiftError);
1057  newFunction->addParamAttr(SwiftErrArgNo, Attribute::SwiftError);
1058  }
1059 
1060  Function::arg_iterator OutputArgBegin = newFunction->arg_begin();
1061  unsigned FirstOut = inputs.size();
1062  if (!AggregateArgs)
1063  std::advance(OutputArgBegin, inputs.size());
1064 
1065  // Reload the outputs passed in by reference.
1066  for (unsigned i = 0, e = outputs.size(); i != e; ++i) {
1067  Value *Output = nullptr;
1068  if (AggregateArgs) {
1069  Value *Idx[2];
1070  Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
1071  Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), FirstOut + i);
1073  StructArgTy, Struct, Idx, "gep_reload_" + outputs[i]->getName());
1074  codeReplacer->getInstList().push_back(GEP);
1075  Output = GEP;
1076  } else {
1077  Output = ReloadOutputs[i];
1078  }
1079  LoadInst *load = new LoadInst(outputs[i]->getType(), Output,
1080  outputs[i]->getName() + ".reload");
1081  Reloads.push_back(load);
1082  codeReplacer->getInstList().push_back(load);
1083  std::vector<User *> Users(outputs[i]->user_begin(), outputs[i]->user_end());
1084  for (unsigned u = 0, e = Users.size(); u != e; ++u) {
1085  Instruction *inst = cast<Instruction>(Users[u]);
1086  if (!Blocks.count(inst->getParent()))
1087  inst->replaceUsesOfWith(outputs[i], load);
1088  }
1089  }
1090 
1091  // Now we can emit a switch statement using the call as a value.
1092  SwitchInst *TheSwitch =
1094  codeReplacer, 0, codeReplacer);
1095 
1096  // Since there may be multiple exits from the original region, make the new
1097  // function return an unsigned, switch on that number. This loop iterates
1098  // over all of the blocks in the extracted region, updating any terminator
1099  // instructions in the to-be-extracted region that branch to blocks that are
1100  // not in the region to be extracted.
1101  std::map<BasicBlock *, BasicBlock *> ExitBlockMap;
1102 
1103  unsigned switchVal = 0;
1104  for (BasicBlock *Block : Blocks) {
1105  Instruction *TI = Block->getTerminator();
1106  for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
1107  if (!Blocks.count(TI->getSuccessor(i))) {
1108  BasicBlock *OldTarget = TI->getSuccessor(i);
1109  // add a new basic block which returns the appropriate value
1110  BasicBlock *&NewTarget = ExitBlockMap[OldTarget];
1111  if (!NewTarget) {
1112  // If we don't already have an exit stub for this non-extracted
1113  // destination, create one now!
1114  NewTarget = BasicBlock::Create(Context,
1115  OldTarget->getName() + ".exitStub",
1116  newFunction);
1117  unsigned SuccNum = switchVal++;
1118 
1119  Value *brVal = nullptr;
1120  switch (NumExitBlocks) {
1121  case 0:
1122  case 1: break; // No value needed.
1123  case 2: // Conditional branch, return a bool
1124  brVal = ConstantInt::get(Type::getInt1Ty(Context), !SuccNum);
1125  break;
1126  default:
1127  brVal = ConstantInt::get(Type::getInt16Ty(Context), SuccNum);
1128  break;
1129  }
1130 
1131  ReturnInst::Create(Context, brVal, NewTarget);
1132 
1133  // Update the switch instruction.
1134  TheSwitch->addCase(ConstantInt::get(Type::getInt16Ty(Context),
1135  SuccNum),
1136  OldTarget);
1137  }
1138 
1139  // rewrite the original branch instruction with this new target
1140  TI->setSuccessor(i, NewTarget);
1141  }
1142  }
1143 
1144  // Store the arguments right after the definition of output value.
1145  // This should be proceeded after creating exit stubs to be ensure that invoke
1146  // result restore will be placed in the outlined function.
1147  Function::arg_iterator OAI = OutputArgBegin;
1148  for (unsigned i = 0, e = outputs.size(); i != e; ++i) {
1149  auto *OutI = dyn_cast<Instruction>(outputs[i]);
1150  if (!OutI)
1151  continue;
1152 
1153  // Find proper insertion point.
1154  BasicBlock::iterator InsertPt;
1155  // In case OutI is an invoke, we insert the store at the beginning in the
1156  // 'normal destination' BB. Otherwise we insert the store right after OutI.
1157  if (auto *InvokeI = dyn_cast<InvokeInst>(OutI))
1158  InsertPt = InvokeI->getNormalDest()->getFirstInsertionPt();
1159  else if (auto *Phi = dyn_cast<PHINode>(OutI))
1160  InsertPt = Phi->getParent()->getFirstInsertionPt();
1161  else
1162  InsertPt = std::next(OutI->getIterator());
1163 
1164  Instruction *InsertBefore = &*InsertPt;
1165  assert((InsertBefore->getFunction() == newFunction ||
1166  Blocks.count(InsertBefore->getParent())) &&
1167  "InsertPt should be in new function");
1168  assert(OAI != newFunction->arg_end() &&
1169  "Number of output arguments should match "
1170  "the amount of defined values");
1171  if (AggregateArgs) {
1172  Value *Idx[2];
1173  Idx[0] = Constant::getNullValue(Type::getInt32Ty(Context));
1174  Idx[1] = ConstantInt::get(Type::getInt32Ty(Context), FirstOut + i);
1176  StructArgTy, &*OAI, Idx, "gep_" + outputs[i]->getName(),
1177  InsertBefore);
1178  new StoreInst(outputs[i], GEP, InsertBefore);
1179  // Since there should be only one struct argument aggregating
1180  // all the output values, we shouldn't increment OAI, which always
1181  // points to the struct argument, in this case.
1182  } else {
1183  new StoreInst(outputs[i], &*OAI, InsertBefore);
1184  ++OAI;
1185  }
1186  }
1187 
1188  // Now that we've done the deed, simplify the switch instruction.
1189  Type *OldFnRetTy = TheSwitch->getParent()->getParent()->getReturnType();
1190  switch (NumExitBlocks) {
1191  case 0:
1192  // There are no successors (the block containing the switch itself), which
1193  // means that previously this was the last part of the function, and hence
1194  // this should be rewritten as a `ret'
1195 
1196  // Check if the function should return a value
1197  if (OldFnRetTy->isVoidTy()) {
1198  ReturnInst::Create(Context, nullptr, TheSwitch); // Return void
1199  } else if (OldFnRetTy == TheSwitch->getCondition()->getType()) {
1200  // return what we have
1201  ReturnInst::Create(Context, TheSwitch->getCondition(), TheSwitch);
1202  } else {
1203  // Otherwise we must have code extracted an unwind or something, just
1204  // return whatever we want.
1205  ReturnInst::Create(Context,
1206  Constant::getNullValue(OldFnRetTy), TheSwitch);
1207  }
1208 
1209  TheSwitch->eraseFromParent();
1210  break;
1211  case 1:
1212  // Only a single destination, change the switch into an unconditional
1213  // branch.
1214  BranchInst::Create(TheSwitch->getSuccessor(1), TheSwitch);
1215  TheSwitch->eraseFromParent();
1216  break;
1217  case 2:
1218  BranchInst::Create(TheSwitch->getSuccessor(1), TheSwitch->getSuccessor(2),
1219  call, TheSwitch);
1220  TheSwitch->eraseFromParent();
1221  break;
1222  default:
1223  // Otherwise, make the default destination of the switch instruction be one
1224  // of the other successors.
1225  TheSwitch->setCondition(call);
1226  TheSwitch->setDefaultDest(TheSwitch->getSuccessor(NumExitBlocks));
1227  // Remove redundant case
1228  TheSwitch->removeCase(SwitchInst::CaseIt(TheSwitch, NumExitBlocks-1));
1229  break;
1230  }
1231 
1232  // Insert lifetime markers around the reloads of any output values. The
1233  // allocas output values are stored in are only in-use in the codeRepl block.
1234  insertLifetimeMarkersSurroundingCall(M, ReloadOutputs, ReloadOutputs, call);
1235 
1236  return call;
1237 }
1238 
1239 void CodeExtractor::moveCodeToFunction(Function *newFunction) {
1240  Function *oldFunc = (*Blocks.begin())->getParent();
1241  Function::BasicBlockListType &oldBlocks = oldFunc->getBasicBlockList();
1242  Function::BasicBlockListType &newBlocks = newFunction->getBasicBlockList();
1243 
1244  for (BasicBlock *Block : Blocks) {
1245  // Delete the basic block from the old function, and the list of blocks
1246  oldBlocks.remove(Block);
1247 
1248  // Insert this basic block into the new function
1249  newBlocks.push_back(Block);
1250 
1251  // Remove @llvm.assume calls that were moved to the new function from the
1252  // old function's assumption cache.
1253  if (AC)
1254  for (auto &I : *Block)
1255  if (match(&I, m_Intrinsic<Intrinsic::assume>()))
1256  AC->unregisterAssumption(cast<CallInst>(&I));
1257  }
1258 }
1259 
1260 void CodeExtractor::calculateNewCallTerminatorWeights(
1261  BasicBlock *CodeReplacer,
1263  BranchProbabilityInfo *BPI) {
1264  using Distribution = BlockFrequencyInfoImplBase::Distribution;
1265  using BlockNode = BlockFrequencyInfoImplBase::BlockNode;
1266 
1267  // Update the branch weights for the exit block.
1268  Instruction *TI = CodeReplacer->getTerminator();
1269  SmallVector<unsigned, 8> BranchWeights(TI->getNumSuccessors(), 0);
1270 
1271  // Block Frequency distribution with dummy node.
1272  Distribution BranchDist;
1273 
1274  // Add each of the frequencies of the successors.
1275  for (unsigned i = 0, e = TI->getNumSuccessors(); i < e; ++i) {
1276  BlockNode ExitNode(i);
1277  uint64_t ExitFreq = ExitWeights[TI->getSuccessor(i)].getFrequency();
1278  if (ExitFreq != 0)
1279  BranchDist.addExit(ExitNode, ExitFreq);
1280  else
1281  BPI->setEdgeProbability(CodeReplacer, i, BranchProbability::getZero());
1282  }
1283 
1284  // Check for no total weight.
1285  if (BranchDist.Total == 0)
1286  return;
1287 
1288  // Normalize the distribution so that they can fit in unsigned.
1289  BranchDist.normalize();
1290 
1291  // Create normalized branch weights and set the metadata.
1292  for (unsigned I = 0, E = BranchDist.Weights.size(); I < E; ++I) {
1293  const auto &Weight = BranchDist.Weights[I];
1294 
1295  // Get the weight and update the current BFI.
1296  BranchWeights[Weight.TargetNode.Index] = Weight.Amount;
1297  BranchProbability BP(Weight.Amount, BranchDist.Total);
1298  BPI->setEdgeProbability(CodeReplacer, Weight.TargetNode.Index, BP);
1299  }
1300  TI->setMetadata(
1302  MDBuilder(TI->getContext()).createBranchWeights(BranchWeights));
1303 }
1304 
1306  if (!isEligible())
1307  return nullptr;
1308 
1309  // Assumption: this is a single-entry code region, and the header is the first
1310  // block in the region.
1311  BasicBlock *header = *Blocks.begin();
1312  Function *oldFunction = header->getParent();
1313 
1314  // For functions with varargs, check that varargs handling is only done in the
1315  // outlined function, i.e vastart and vaend are only used in outlined blocks.
1316  if (AllowVarArgs && oldFunction->getFunctionType()->isVarArg()) {
1317  auto containsVarArgIntrinsic = [](Instruction &I) {
1318  if (const CallInst *CI = dyn_cast<CallInst>(&I))
1319  if (const Function *F = CI->getCalledFunction())
1320  return F->getIntrinsicID() == Intrinsic::vastart ||
1321  F->getIntrinsicID() == Intrinsic::vaend;
1322  return false;
1323  };
1324 
1325  for (auto &BB : *oldFunction) {
1326  if (Blocks.count(&BB))
1327  continue;
1328  if (llvm::any_of(BB, containsVarArgIntrinsic))
1329  return nullptr;
1330  }
1331  }
1332  ValueSet inputs, outputs, SinkingCands, HoistingCands;
1333  BasicBlock *CommonExit = nullptr;
1334 
1335  // Calculate the entry frequency of the new function before we change the root
1336  // block.
1337  BlockFrequency EntryFreq;
1338  if (BFI) {
1339  assert(BPI && "Both BPI and BFI are required to preserve profile info");
1340  for (BasicBlock *Pred : predecessors(header)) {
1341  if (Blocks.count(Pred))
1342  continue;
1343  EntryFreq +=
1344  BFI->getBlockFreq(Pred) * BPI->getEdgeProbability(Pred, header);
1345  }
1346  }
1347 
1348  // If we have any return instructions in the region, split those blocks so
1349  // that the return is not in the region.
1350  splitReturnBlocks();
1351 
1352  // Calculate the exit blocks for the extracted region and the total exit
1353  // weights for each of those blocks.
1355  SmallPtrSet<BasicBlock *, 1> ExitBlocks;
1356  for (BasicBlock *Block : Blocks) {
1357  for (succ_iterator SI = succ_begin(Block), SE = succ_end(Block); SI != SE;
1358  ++SI) {
1359  if (!Blocks.count(*SI)) {
1360  // Update the branch weight for this successor.
1361  if (BFI) {
1362  BlockFrequency &BF = ExitWeights[*SI];
1363  BF += BFI->getBlockFreq(Block) * BPI->getEdgeProbability(Block, *SI);
1364  }
1365  ExitBlocks.insert(*SI);
1366  }
1367  }
1368  }
1369  NumExitBlocks = ExitBlocks.size();
1370 
1371  // If we have to split PHI nodes of the entry or exit blocks, do so now.
1372  severSplitPHINodesOfEntry(header);
1373  severSplitPHINodesOfExits(ExitBlocks);
1374 
1375  // This takes place of the original loop
1376  BasicBlock *codeReplacer = BasicBlock::Create(header->getContext(),
1377  "codeRepl", oldFunction,
1378  header);
1379 
1380  // The new function needs a root node because other nodes can branch to the
1381  // head of the region, but the entry node of a function cannot have preds.
1382  BasicBlock *newFuncRoot = BasicBlock::Create(header->getContext(),
1383  "newFuncRoot");
1384  auto *BranchI = BranchInst::Create(header);
1385  // If the original function has debug info, we have to add a debug location
1386  // to the new branch instruction from the artificial entry block.
1387  // We use the debug location of the first instruction in the extracted
1388  // blocks, as there is no other equivalent line in the source code.
1389  if (oldFunction->getSubprogram()) {
1390  any_of(Blocks, [&BranchI](const BasicBlock *BB) {
1391  return any_of(*BB, [&BranchI](const Instruction &I) {
1392  if (!I.getDebugLoc())
1393  return false;
1394  BranchI->setDebugLoc(I.getDebugLoc());
1395  return true;
1396  });
1397  });
1398  }
1399  newFuncRoot->getInstList().push_back(BranchI);
1400 
1401  findAllocas(SinkingCands, HoistingCands, CommonExit);
1402  assert(HoistingCands.empty() || CommonExit);
1403 
1404  // Find inputs to, outputs from the code region.
1405  findInputsOutputs(inputs, outputs, SinkingCands);
1406 
1407  // Now sink all instructions which only have non-phi uses inside the region
1408  for (auto *II : SinkingCands)
1409  cast<Instruction>(II)->moveBefore(*newFuncRoot,
1410  newFuncRoot->getFirstInsertionPt());
1411 
1412  if (!HoistingCands.empty()) {
1413  auto *HoistToBlock = findOrCreateBlockForHoisting(CommonExit);
1414  Instruction *TI = HoistToBlock->getTerminator();
1415  for (auto *II : HoistingCands)
1416  cast<Instruction>(II)->moveBefore(TI);
1417  }
1418 
1419  // Collect objects which are inputs to the extraction region and also
1420  // referenced by lifetime start markers within it. The effects of these
1421  // markers must be replicated in the calling function to prevent the stack
1422  // coloring pass from merging slots which store input objects.
1423  ValueSet LifetimesStart;
1424  eraseLifetimeMarkersOnInputs(Blocks, SinkingCands, LifetimesStart);
1425 
1426  // Construct new function based on inputs/outputs & add allocas for all defs.
1427  Function *newFunction =
1428  constructFunction(inputs, outputs, header, newFuncRoot, codeReplacer,
1429  oldFunction, oldFunction->getParent());
1430 
1431  // Update the entry count of the function.
1432  if (BFI) {
1433  auto Count = BFI->getProfileCountFromFreq(EntryFreq.getFrequency());
1434  if (Count.hasValue())
1435  newFunction->setEntryCount(
1436  ProfileCount(Count.getValue(), Function::PCT_Real)); // FIXME
1437  BFI->setBlockFreq(codeReplacer, EntryFreq.getFrequency());
1438  }
1439 
1440  CallInst *TheCall =
1441  emitCallAndSwitchStatement(newFunction, codeReplacer, inputs, outputs);
1442 
1443  moveCodeToFunction(newFunction);
1444 
1445  // Replicate the effects of any lifetime start/end markers which referenced
1446  // input objects in the extraction region by placing markers around the call.
1448  oldFunction->getParent(), LifetimesStart.getArrayRef(), {}, TheCall);
1449 
1450  // Propagate personality info to the new function if there is one.
1451  if (oldFunction->hasPersonalityFn())
1452  newFunction->setPersonalityFn(oldFunction->getPersonalityFn());
1453 
1454  // Update the branch weights for the exit block.
1455  if (BFI && NumExitBlocks > 1)
1456  calculateNewCallTerminatorWeights(codeReplacer, ExitWeights, BPI);
1457 
1458  // Loop over all of the PHI nodes in the header and exit blocks, and change
1459  // any references to the old incoming edge to be the new incoming edge.
1460  for (BasicBlock::iterator I = header->begin(); isa<PHINode>(I); ++I) {
1461  PHINode *PN = cast<PHINode>(I);
1462  for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
1463  if (!Blocks.count(PN->getIncomingBlock(i)))
1464  PN->setIncomingBlock(i, newFuncRoot);
1465  }
1466 
1467  for (BasicBlock *ExitBB : ExitBlocks)
1468  for (PHINode &PN : ExitBB->phis()) {
1469  Value *IncomingCodeReplacerVal = nullptr;
1470  for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1471  // Ignore incoming values from outside of the extracted region.
1472  if (!Blocks.count(PN.getIncomingBlock(i)))
1473  continue;
1474 
1475  // Ensure that there is only one incoming value from codeReplacer.
1476  if (!IncomingCodeReplacerVal) {
1477  PN.setIncomingBlock(i, codeReplacer);
1478  IncomingCodeReplacerVal = PN.getIncomingValue(i);
1479  } else
1480  assert(IncomingCodeReplacerVal == PN.getIncomingValue(i) &&
1481  "PHI has two incompatbile incoming values from codeRepl");
1482  }
1483  }
1484 
1485  // Erase debug info intrinsics. Variable updates within the new function are
1486  // invisible to debuggers. This could be improved by defining a DISubprogram
1487  // for the new function.
1488  for (BasicBlock &BB : *newFunction) {
1489  auto BlockIt = BB.begin();
1490  // Remove debug info intrinsics from the new function.
1491  while (BlockIt != BB.end()) {
1492  Instruction *Inst = &*BlockIt;
1493  ++BlockIt;
1494  if (isa<DbgInfoIntrinsic>(Inst))
1495  Inst->eraseFromParent();
1496  }
1497  // Remove debug info intrinsics which refer to values in the new function
1498  // from the old function.
1500  for (Instruction &I : BB)
1501  findDbgUsers(DbgUsers, &I);
1502  for (DbgVariableIntrinsic *DVI : DbgUsers)
1503  DVI->eraseFromParent();
1504  }
1505 
1506  // Mark the new function `noreturn` if applicable. Terminators which resume
1507  // exception propagation are treated as returning instructions. This is to
1508  // avoid inserting traps after calls to outlined functions which unwind.
1509  bool doesNotReturn = none_of(*newFunction, [](const BasicBlock &BB) {
1510  const Instruction *Term = BB.getTerminator();
1511  return isa<ReturnInst>(Term) || isa<ResumeInst>(Term);
1512  });
1513  if (doesNotReturn)
1514  newFunction->setDoesNotReturn();
1515 
1516  LLVM_DEBUG(if (verifyFunction(*newFunction, &errs())) {
1517  newFunction->dump();
1518  report_fatal_error("verification of newFunction failed!");
1519  });
1520  LLVM_DEBUG(if (verifyFunction(*oldFunction))
1521  report_fatal_error("verification of oldFunction failed!"));
1522  return newFunction;
1523 }
bool isVarArg() const
isVarArg - Return true if this function takes a variable number of arguments.
Definition: Function.h:176
static BasicBlock * getCommonExitBlock(const SetVector< BasicBlock *> &Blocks)
Return a value (possibly void), from a function.
SymbolTableList< Instruction >::iterator eraseFromParent()
This method unlinks &#39;this&#39; from the containing basic block and deletes it.
Definition: Instruction.cpp:67
A parsed version of the target data layout string in and methods for querying it. ...
Definition: DataLayout.h:110
raw_ostream & errs()
This returns a reference to a raw_ostream for standard error.
static IntegerType * getInt1Ty(LLVMContext &C)
Definition: Type.cpp:172
void addIncoming(Value *V, BasicBlock *BB)
Add an incoming value to the end of the PHI list.
This class represents an incoming formal argument to a Function.
Definition: Argument.h:29
LLVM_NODISCARD std::string str() const
str - Get the contents as an std::string.
Definition: StringRef.h:218
LLVMContext & Context
const Value * stripInBoundsOffsets() const
Strip off pointer casts and inbounds GEPs.
Definition: Value.cpp:589
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:139
This class represents lattice values for constants.
Definition: AllocatorList.h:23
ArrayRef< T > getArrayRef() const
Definition: SetVector.h:63
size_type size() const
Determine the number of elements in the SetVector.
Definition: SetVector.h:77
void addParamAttr(unsigned ArgNo, Attribute::AttrKind Kind)
adds the attribute to the list of attributes for the given arg.
Definition: Function.cpp:385
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:64
void findInputsOutputs(ValueSet &Inputs, ValueSet &Outputs, const ValueSet &Allocas) const
Compute the set of input values and output values for the code.
BasicBlock * getSuccessor(unsigned Idx) const
Return the specified successor. This instruction must be a terminator.
static CallInst * Create(FunctionType *Ty, Value *F, const Twine &NameStr="", Instruction *InsertBefore=nullptr)
static cl::opt< bool > AggregateArgsOpt("aggregate-extracted-args", cl::Hidden, cl::desc("Aggregate arguments to code-extracted functions"))
void addCase(ConstantInt *OnVal, BasicBlock *Dest)
Add an entry to the switch instruction.
static GetElementPtrInst * Create(Type *PointeeType, Value *Ptr, ArrayRef< Value *> IdxList, const Twine &NameStr="", Instruction *InsertBefore=nullptr)
Definition: Instructions.h:899
void findDbgUsers(SmallVectorImpl< DbgVariableIntrinsic *> &DbgInsts, Value *V)
Finds the debug info intrinsics describing a value.
Definition: Local.cpp:1519
This class represents a function call, abstracting a target machine&#39;s calling convention.
Value * getCondition() const
The two locations do not alias at all.
Definition: AliasAnalysis.h:83
A cache of @llvm.assume calls within a function.
uint64_t getFrequency() const
Returns the frequency as a fixpoint number scaled by the entry frequency.
Function * extractCodeRegion()
Perform the extraction, returning the new function.
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:705
arg_iterator arg_end()
Definition: Function.h:679
F(f)
An instruction for reading from memory.
Definition: Instructions.h:167
static IntegerType * getInt64Ty(LLVMContext &C)
Definition: Type.cpp:176
Hexagon Common GEP
const Instruction * 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:137
void setSuccessor(unsigned Idx, BasicBlock *BB)
Update the specified successor to point at the provided block.
iv Induction Variable Users
Definition: IVUsers.cpp:51
static IntegerType * getInt16Ty(LLVMContext &C)
Definition: Type.cpp:174
LLVMContext & getContext() const
Get the context in which this basic block lives.
Definition: BasicBlock.cpp:32
bool isReachableFromEntry(const Use &U) const
Provide an overload for a Use.
Definition: Dominators.cpp:299
static Constant * getNullValue(Type *Ty)
Constructor to create a &#39;0&#39; constant of arbitrary type.
Definition: Constants.cpp:264
A templated base class for SmallPtrSet which provides the typesafe interface that is common across al...
Definition: SmallPtrSet.h:343
iterator begin()
Instruction iterator methods.
Definition: BasicBlock.h:268
static void insertLifetimeMarkersSurroundingCall(Module *M, ArrayRef< Value *> LifetimesStart, ArrayRef< Value *> LifetimesEnd, CallInst *TheCall)
Insert lifetime start/end markers surrounding the call to the new function for objects defined in the...
void setDoesNotThrow()
Definition: Function.h:522
static ReturnInst * Create(LLVMContext &C, Value *retVal=nullptr, Instruction *InsertBefore=nullptr)
static bool isBlockValidForExtraction(const BasicBlock &BB, const SetVector< BasicBlock *> &Result, bool AllowVarArgs, bool AllowAlloca)
Test whether a block is valid for extraction.
bool match(Val *V, const Pattern &P)
Definition: PatternMatch.h:47
unsigned getAllocaAddrSpace() const
Definition: DataLayout.h:257
static void eraseLifetimeMarkersOnInputs(const SetVector< BasicBlock *> &Blocks, const SetVector< Value *> &SunkAllocas, SetVector< Value *> &LifetimesStart)
Erase lifetime.start markers which reference inputs to the extraction region, and insert the referenc...
Value * removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty=true)
Remove an incoming value.
const DataLayout & getDataLayout() const
Get the data layout for the module&#39;s target platform.
Definition: Module.cpp:369
void setEntryCount(ProfileCount Count, const DenseSet< GlobalValue::GUID > *Imports=nullptr)
Set the entry count for this function.
Definition: Function.cpp:1366
static bool definedInCaller(const SetVector< BasicBlock *> &Blocks, Value *V)
definedInCaller - Return true if the specified value is defined in the function being code extracted...
Class to represent struct types.
Definition: DerivedTypes.h:232
LLVMContext & getContext() const
Get the global data context.
Definition: Module.h:243
A Use represents the edge between a Value definition and its users.
Definition: Use.h:55
bool hasUWTable() const
True if the ABI mandates (or the user requested) that this function be in a unwind table...
Definition: Function.h:564
bool none_of(R &&Range, UnaryPredicate P)
Provide wrappers to std::none_of which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1199
static StringRef getName(Value *V)
This file contains the simple types necessary to represent the attributes associated with functions a...
No attributes have been set.
Definition: Attributes.h:71
static SetVector< BasicBlock * > buildExtractionBlockSet(ArrayRef< BasicBlock *> BBs, DominatorTree *DT, bool AllowVarArgs, bool AllowAlloca)
Build a set of blocks to extract if the input blocks are viable.
void setName(const Twine &Name)
Change the name of the value.
Definition: Value.cpp:285
void unregisterAssumption(CallInst *CI)
Remove an @llvm.assume intrinsic from this function&#39;s cache if it has been added to the cache earlier...
LLVM_NODISCARD bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:126
static StructType * get(LLVMContext &Context, ArrayRef< Type *> Elements, bool isPacked=false)
This static method is the primary way to create a literal StructType.
Definition: Type.cpp:341
Interval::succ_iterator succ_begin(Interval *I)
succ_begin/succ_end - define methods so that Intervals may be used just like BasicBlocks can with the...
Definition: Interval.h:102
auto reverse(ContainerTy &&C, typename std::enable_if< has_rbegin< ContainerTy >::value >::type *=nullptr) -> decltype(make_range(C.rbegin(), C.rend()))
Definition: STLExtras.h:266
Class to represent function types.
Definition: DerivedTypes.h:102
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:244
bool insert(const value_type &X)
Insert a new element into the SetVector.
Definition: SetVector.h:141
This is the common base class for debug info intrinsics for variables.
Definition: IntrinsicInst.h:87
bool isVarArg() const
Definition: DerivedTypes.h:122
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
AttributeList getAttributes() const
Return the attribute list for this Function.
Definition: Function.h:223
An instruction for storing to memory.
Definition: Instructions.h:320
bool hasPersonalityFn() const
Check whether this function has a personality function.
Definition: Function.h:701
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:429
BasicBlock * getSuccessor(unsigned idx) const
static Function * getFunction(Constant *C)
Definition: Evaluator.cpp:220
iterator begin()
Definition: Function.h:655
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree...
Definition: Dominators.h:144
Function * getDeclaration(Module *M, ID id, ArrayRef< Type *> Tys=None)
Create or insert an LLVM Function declaration for an intrinsic, and return it.
Definition: Function.cpp:1018
unsigned getNumSuccessors() const
Return the number of successors that this instruction has.
size_type count(const key_type &key) const
Count the number of elements of a given key in the SetVector.
Definition: SetVector.h:210
Interval::succ_iterator succ_end(Interval *I)
Definition: Interval.h:105
void replaceUsesOfWith(Value *From, Value *To)
Replace uses of one Value with another.
Definition: User.cpp:20
static bool definedInRegion(const SetVector< BasicBlock *> &Blocks, Value *V)
definedInRegion - Return true if the specified value is defined in the extracted region.
bool isVoidTy() const
Return true if this is &#39;void&#39;.
Definition: Type.h:140
const BasicBlock & getEntryBlock() const
Definition: Function.h:639
an instruction for type-safe pointer arithmetic to access elements of arrays and structs ...
Definition: Instructions.h:873
BlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation to estimate IR basic block frequen...
Type * getReturnType() const
Returns the type of the ret val.
Definition: Function.h:168
static Function * Create(FunctionType *Ty, LinkageTypes Linkage, unsigned AddrSpace, const Twine &N="", Module *M=nullptr)
Definition: Function.h:135
const Instruction * getFirstNonPHI() const
Returns a pointer to the first instruction in this block that is not a PHINode instruction.
Definition: BasicBlock.cpp:189
void setDebugLoc(DebugLoc Loc)
Set the debug location information for this instruction.
Definition: Instruction.h:321
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:57
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:68
DISubprogram * getSubprogram() const
Get the attached subprogram.
Definition: Metadata.cpp:1507
void changeImmediateDominator(DomTreeNodeBase< NodeT > *N, DomTreeNodeBase< NodeT > *NewIDom)
changeImmediateDominator - This method is used to update the dominator tree information when a node&#39;s...
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This file contains the declarations for the subclasses of Constant, which represent the different fla...
const Instruction & front() const
Definition: BasicBlock.h:280
Distribution of unscaled probability weight.
std::pair< iterator, bool > insert(PtrType Ptr)
Inserts Ptr if and only if there is no element in the container equal to Ptr.
Definition: SmallPtrSet.h:370
Interval::pred_iterator pred_begin(Interval *I)
pred_begin/pred_end - define methods so that Intervals may be used just like BasicBlocks can with the...
Definition: Interval.h:112
bool isLifetimeStartOrEnd() const
Return true if the instruction is a llvm.lifetime.start or llvm.lifetime.end marker.
static Type * getVoidTy(LLVMContext &C)
Definition: Type.cpp:160
bool any_of(R &&range, UnaryPredicate P)
Provide wrappers to std::any_of which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1192
unsigned getAddressSpace() const
Definition: Globals.cpp:110
static FunctionType * get(Type *Result, ArrayRef< Type *> Params, bool isVarArg)
This static method is the primary way of constructing a FunctionType.
Definition: Type.cpp:296
Interval::pred_iterator pred_end(Interval *I)
Definition: Interval.h:115
op_range operands()
Definition: User.h:237
Value * getPointerOperand()
Definition: Instructions.h:284
static BasicBlock * Create(LLVMContext &Context, const Twine &Name="", Function *Parent=nullptr, BasicBlock *InsertBefore=nullptr)
Creates a new BasicBlock.
Definition: BasicBlock.h:99
arg_iterator arg_begin()
Definition: Function.h:670
self_iterator getIterator()
Definition: ilist_node.h:81
void setHasUWTable()
Definition: Function.h:567
static CastInst * CreatePointerCast(Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd)
Create a BitCast AddrSpaceCast, or a PtrToInt cast instruction.
const Function * getFunction() const
Return the function this instruction belongs to.
Definition: Instruction.cpp:59
CaseIt removeCase(CaseIt I)
This method removes the specified case and its successor from the switch instruction.
Sentinal value useful for loops.
Definition: Attributes.h:74
LLVMContext & getContext() const
getContext - Return a reference to the LLVMContext associated with this function. ...
Definition: Function.cpp:192
Class to represent profile counts.
Definition: Function.h:260
size_t size() const
Definition: SmallVector.h:52
static wasm::ValType getType(const TargetRegisterClass *RC)
Value * getIncomingValue(unsigned i) const
Return incoming value number x.
DomTreeNodeBase< NodeT > * getNode(const NodeT *BB) const
getNode - return the (Post)DominatorTree node for the specified basic block.
static PointerType * getInt8PtrTy(LLVMContext &C, unsigned AS=0)
Definition: Type.cpp:219
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void setMetadata(unsigned KindID, MDNode *Node)
Set the metadata of the specified kind to the specified node.
Definition: Metadata.cpp:1225
BranchProbability getEdgeProbability(const BasicBlock *Src, unsigned IndexInSuccessors) const
Get an edge&#39;s probability, relative to other out-edges of the Src.
Intrinsic::ID getIntrinsicID() const
Return the intrinsic ID of this intrinsic.
Definition: IntrinsicInst.h:50
bool doesNotThrow() const
Determine if the function cannot unwind.
Definition: Function.h:519
size_type size() const
Definition: SmallPtrSet.h:92
bool hasAddressTaken() const
Returns true if there are any uses of this basic block other than direct branches, switches, etc.
Definition: BasicBlock.h:391
const InstListType & getInstList() const
Return the underlying instruction list container.
Definition: BasicBlock.h:333
typename vector_type::const_iterator iterator
Definition: SetVector.h:48
void addParamAttr(unsigned ArgNo, Attribute::AttrKind Kind)
Adds the attribute to the indicated argument.
Definition: InstrTypes.h:1311
Iterator for intrusive lists based on ilist_node.
SmallPtrSet - This class implements a set which is optimized for holding SmallSize or less elements...
Definition: SmallPtrSet.h:417
static PointerType * getUnqual(Type *ElementType)
This constructs a pointer to an object of the specified type in the generic address space (address sp...
Definition: DerivedTypes.h:513
void setIncomingBlock(unsigned i, BasicBlock *BB)
static SwitchInst * Create(Value *Value, BasicBlock *Default, unsigned NumCases, Instruction *InsertBefore=nullptr)
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:839
Module.h This file contains the declarations for the Module class.
CodeExtractor(ArrayRef< BasicBlock *> BBs, DominatorTree *DT=nullptr, bool AggregateArgs=false, BlockFrequencyInfo *BFI=nullptr, BranchProbabilityInfo *BPI=nullptr, AssumptionCache *AC=nullptr, bool AllowVarArgs=false, bool AllowAlloca=false, std::string Suffix="")
Create a code extractor for a sequence of blocks.
void setEdgeProbability(const BasicBlock *Src, unsigned IndexInSuccessors, BranchProbability Prob)
Set the raw edge probability for the given edge.
void setBlockFreq(const BasicBlock *BB, uint64_t Freq)
LLVM_NODISCARD T pop_back_val()
Definition: SmallVector.h:373
bool isEligible() const
Test whether this code extractor is eligible.
static Constant * get(Type *Ty, uint64_t V, bool isSigned=false)
If Ty is a vector type, return a Constant with a splat of the given value.
Definition: Constants.cpp:621
static ConstantInt * getSigned(IntegerType *Ty, int64_t V)
Return a ConstantInt with the specified value for the specified type.
Definition: Constants.cpp:635
static BranchInst * Create(BasicBlock *IfTrue, Instruction *InsertBefore=nullptr)
static PHINode * Create(Type *Ty, unsigned NumReservedValues, const Twine &NameStr="", Instruction *InsertBefore=nullptr)
Constructors - NumReservedValues is a hint for the number of incoming edges that this phi node will h...
pred_range predecessors(BasicBlock *BB)
Definition: CFG.h:124
unsigned getNumIncomingValues() const
Return the number of incoming edges.
BlockFrequency getBlockFreq(const BasicBlock *BB) const
getblockFreq - Return block frequency.
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
FunctionType * getFunctionType() const
Returns the FunctionType for me.
Definition: Function.h:163
bool isLegalToShrinkwrapLifetimeMarkers(Instruction *AllocaAddr) const
Check if life time marker nodes can be hoisted/sunk into the outline region.
BasicBlock * findOrCreateBlockForHoisting(BasicBlock *CommonExitBlock)
Find or create a block within the outline region for placing hoisted code.
void push_back(pointer val)
Definition: ilist.h:311
iterator_range< user_iterator > users()
Definition: Value.h:399
Function::ProfileCount ProfileCount
This file provides various utilities for inspecting and working with the control flow graph in LLVM I...
pointer remove(iterator &IT)
Definition: ilist.h:249
Analysis providing branch probability information.
const DebugLoc & getDebugLoc() const
Return the debug location for this node as a DebugLoc.
Definition: Instruction.h:324
static IntegerType * getInt32Ty(LLVMContext &C)
Definition: Type.cpp:175
void setCondition(Value *V)
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:55
Represents a single loop in the control flow graph.
Definition: LoopInfo.h:464
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:214
BasicBlock * getIncomingBlock(unsigned i) const
Return incoming basic block number i.
const Function * getParent() const
Return the enclosing method, or null if none.
Definition: BasicBlock.h:106
#define I(x, y, z)
Definition: MD5.cpp:58
DomTreeNodeBase< NodeT > * addNewBlock(NodeT *BB, NodeT *DomBB)
Add a new node to the dominator tree information.
bool empty() const
Determine if the SetVector is empty or not.
Definition: SetVector.h:72
bool verifyFunction(const Function &F, raw_ostream *OS=nullptr)
Check a function for errors, useful for use when debugging a pass.
Definition: Verifier.cpp:4850
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:322
const BasicBlockListType & getBasicBlockList() const
Get the underlying elements of the Function...
Definition: Function.h:632
Rename collisions when linking (static functions).
Definition: GlobalValue.h:55
BasicBlock * splitBasicBlock(iterator I, const Twine &BBName="")
Split the basic block into two basic blocks at the specified instruction.
Definition: BasicBlock.cpp:407
pgo instr use
Multiway switch.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
user_iterator user_begin()
Definition: Value.h:375
const BasicBlock & front() const
Definition: Function.h:662
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:565
LLVM Value Representation.
Definition: Value.h:72
Constant * getPersonalityFn() const
Get the personality function associated with this function.
Definition: Function.cpp:1302
void setDefaultDest(BasicBlock *DefaultCase)
A vector that has set insertion semantics.
Definition: SetVector.h:40
succ_range successors(Instruction *I)
Definition: CFG.h:259
void findAllocas(ValueSet &SinkCands, ValueSet &HoistCands, BasicBlock *&ExitBlock) const
Find the set of allocas whose life ranges are contained within the outlined region.
static const Function * getParent(const Value *V)
AttributeSet getFnAttributes() const
The function attributes are returned.
BasicBlock * SplitBlock(BasicBlock *Old, Instruction *SplitPt, DominatorTree *DT=nullptr, LoopInfo *LI=nullptr, MemorySSAUpdater *MSSAU=nullptr)
Split the specified block at the specified instruction - everything before SplitPt stays in Old and e...
void addFnAttr(Attribute::AttrKind Kind)
Add function attributes to this function.
Definition: Function.h:229
void setPersonalityFn(Constant *Fn)
Definition: Function.cpp:1307
static BranchProbability getZero()
const Value * stripInBoundsConstantOffsets() const
Strip off pointer casts and all-constant inbounds GEPs.
Definition: Value.cpp:537
#define LLVM_DEBUG(X)
Definition: Debug.h:122
Value * getPointerOperand()
Definition: Instructions.h:412
Optional< uint64_t > getProfileCountFromFreq(uint64_t Freq) const
Returns the estimated profile count of Freq.
bool empty() const
empty - Check if the array is empty.
Definition: ArrayRef.h:143
A wrapper class for inspecting calls to intrinsic functions.
Definition: IntrinsicInst.h:43
const BasicBlock * getParent() const
Definition: Instruction.h:66
an instruction to allocate memory on the stack
Definition: Instructions.h:59
user_iterator user_end()
Definition: Value.h:383