LLVM  6.0.0svn
PHITransAddr.cpp
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1 //===- PHITransAddr.cpp - PHI Translation for Addresses -------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the PHITransAddr class.
11 //
12 //===----------------------------------------------------------------------===//
13 
17 #include "llvm/IR/Constants.h"
18 #include "llvm/IR/Dominators.h"
19 #include "llvm/IR/Instructions.h"
20 #include "llvm/Support/Debug.h"
23 using namespace llvm;
24 
25 static bool CanPHITrans(Instruction *Inst) {
26  if (isa<PHINode>(Inst) ||
27  isa<GetElementPtrInst>(Inst))
28  return true;
29 
30  if (isa<CastInst>(Inst) &&
32  return true;
33 
34  if (Inst->getOpcode() == Instruction::Add &&
35  isa<ConstantInt>(Inst->getOperand(1)))
36  return true;
37 
38  // cerr << "MEMDEP: Could not PHI translate: " << *Pointer;
39  // if (isa<BitCastInst>(PtrInst) || isa<GetElementPtrInst>(PtrInst))
40  // cerr << "OP:\t\t\t\t" << *PtrInst->getOperand(0);
41  return false;
42 }
43 
44 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
46  if (!Addr) {
47  dbgs() << "PHITransAddr: null\n";
48  return;
49  }
50  dbgs() << "PHITransAddr: " << *Addr << "\n";
51  for (unsigned i = 0, e = InstInputs.size(); i != e; ++i)
52  dbgs() << " Input #" << i << " is " << *InstInputs[i] << "\n";
53 }
54 #endif
55 
56 
57 static bool VerifySubExpr(Value *Expr,
58  SmallVectorImpl<Instruction*> &InstInputs) {
59  // If this is a non-instruction value, there is nothing to do.
61  if (!I) return true;
62 
63  // If it's an instruction, it is either in Tmp or its operands recursively
64  // are.
65  SmallVectorImpl<Instruction *>::iterator Entry = find(InstInputs, I);
66  if (Entry != InstInputs.end()) {
67  InstInputs.erase(Entry);
68  return true;
69  }
70 
71  // If it isn't in the InstInputs list it is a subexpr incorporated into the
72  // address. Sanity check that it is phi translatable.
73  if (!CanPHITrans(I)) {
74  errs() << "Instruction in PHITransAddr is not phi-translatable:\n";
75  errs() << *I << '\n';
76  llvm_unreachable("Either something is missing from InstInputs or "
77  "CanPHITrans is wrong.");
78  }
79 
80  // Validate the operands of the instruction.
81  for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
82  if (!VerifySubExpr(I->getOperand(i), InstInputs))
83  return false;
84 
85  return true;
86 }
87 
88 /// Verify - Check internal consistency of this data structure. If the
89 /// structure is valid, it returns true. If invalid, it prints errors and
90 /// returns false.
91 bool PHITransAddr::Verify() const {
92  if (!Addr) return true;
93 
94  SmallVector<Instruction*, 8> Tmp(InstInputs.begin(), InstInputs.end());
95 
96  if (!VerifySubExpr(Addr, Tmp))
97  return false;
98 
99  if (!Tmp.empty()) {
100  errs() << "PHITransAddr contains extra instructions:\n";
101  for (unsigned i = 0, e = InstInputs.size(); i != e; ++i)
102  errs() << " InstInput #" << i << " is " << *InstInputs[i] << "\n";
103  llvm_unreachable("This is unexpected.");
104  }
105 
106  // a-ok.
107  return true;
108 }
109 
110 
111 /// IsPotentiallyPHITranslatable - If this needs PHI translation, return true
112 /// if we have some hope of doing it. This should be used as a filter to
113 /// avoid calling PHITranslateValue in hopeless situations.
115  // If the input value is not an instruction, or if it is not defined in CurBB,
116  // then we don't need to phi translate it.
117  Instruction *Inst = dyn_cast<Instruction>(Addr);
118  return !Inst || CanPHITrans(Inst);
119 }
120 
121 
122 static void RemoveInstInputs(Value *V,
123  SmallVectorImpl<Instruction*> &InstInputs) {
125  if (!I) return;
126 
127  // If the instruction is in the InstInputs list, remove it.
128  SmallVectorImpl<Instruction *>::iterator Entry = find(InstInputs, I);
129  if (Entry != InstInputs.end()) {
130  InstInputs.erase(Entry);
131  return;
132  }
133 
134  assert(!isa<PHINode>(I) && "Error, removing something that isn't an input");
135 
136  // Otherwise, it must have instruction inputs itself. Zap them recursively.
137  for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
138  if (Instruction *Op = dyn_cast<Instruction>(I->getOperand(i)))
139  RemoveInstInputs(Op, InstInputs);
140  }
141 }
142 
143 Value *PHITransAddr::PHITranslateSubExpr(Value *V, BasicBlock *CurBB,
144  BasicBlock *PredBB,
145  const DominatorTree *DT) {
146  // If this is a non-instruction value, it can't require PHI translation.
147  Instruction *Inst = dyn_cast<Instruction>(V);
148  if (!Inst) return V;
149 
150  // Determine whether 'Inst' is an input to our PHI translatable expression.
151  bool isInput = is_contained(InstInputs, Inst);
152 
153  // Handle inputs instructions if needed.
154  if (isInput) {
155  if (Inst->getParent() != CurBB) {
156  // If it is an input defined in a different block, then it remains an
157  // input.
158  return Inst;
159  }
160 
161  // If 'Inst' is defined in this block and is an input that needs to be phi
162  // translated, we need to incorporate the value into the expression or fail.
163 
164  // In either case, the instruction itself isn't an input any longer.
165  InstInputs.erase(find(InstInputs, Inst));
166 
167  // If this is a PHI, go ahead and translate it.
168  if (PHINode *PN = dyn_cast<PHINode>(Inst))
169  return AddAsInput(PN->getIncomingValueForBlock(PredBB));
170 
171  // If this is a non-phi value, and it is analyzable, we can incorporate it
172  // into the expression by making all instruction operands be inputs.
173  if (!CanPHITrans(Inst))
174  return nullptr;
175 
176  // All instruction operands are now inputs (and of course, they may also be
177  // defined in this block, so they may need to be phi translated themselves.
178  for (unsigned i = 0, e = Inst->getNumOperands(); i != e; ++i)
179  if (Instruction *Op = dyn_cast<Instruction>(Inst->getOperand(i)))
180  InstInputs.push_back(Op);
181  }
182 
183  // Ok, it must be an intermediate result (either because it started that way
184  // or because we just incorporated it into the expression). See if its
185  // operands need to be phi translated, and if so, reconstruct it.
186 
187  if (CastInst *Cast = dyn_cast<CastInst>(Inst)) {
188  if (!isSafeToSpeculativelyExecute(Cast)) return nullptr;
189  Value *PHIIn = PHITranslateSubExpr(Cast->getOperand(0), CurBB, PredBB, DT);
190  if (!PHIIn) return nullptr;
191  if (PHIIn == Cast->getOperand(0))
192  return Cast;
193 
194  // Find an available version of this cast.
195 
196  // Constants are trivial to find.
197  if (Constant *C = dyn_cast<Constant>(PHIIn))
198  return AddAsInput(ConstantExpr::getCast(Cast->getOpcode(),
199  C, Cast->getType()));
200 
201  // Otherwise we have to see if a casted version of the incoming pointer
202  // is available. If so, we can use it, otherwise we have to fail.
203  for (User *U : PHIIn->users()) {
204  if (CastInst *CastI = dyn_cast<CastInst>(U))
205  if (CastI->getOpcode() == Cast->getOpcode() &&
206  CastI->getType() == Cast->getType() &&
207  (!DT || DT->dominates(CastI->getParent(), PredBB)))
208  return CastI;
209  }
210  return nullptr;
211  }
212 
213  // Handle getelementptr with at least one PHI translatable operand.
214  if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Inst)) {
215  SmallVector<Value*, 8> GEPOps;
216  bool AnyChanged = false;
217  for (unsigned i = 0, e = GEP->getNumOperands(); i != e; ++i) {
218  Value *GEPOp = PHITranslateSubExpr(GEP->getOperand(i), CurBB, PredBB, DT);
219  if (!GEPOp) return nullptr;
220 
221  AnyChanged |= GEPOp != GEP->getOperand(i);
222  GEPOps.push_back(GEPOp);
223  }
224 
225  if (!AnyChanged)
226  return GEP;
227 
228  // Simplify the GEP to handle 'gep x, 0' -> x etc.
229  if (Value *V = SimplifyGEPInst(GEP->getSourceElementType(),
230  GEPOps, {DL, TLI, DT, AC})) {
231  for (unsigned i = 0, e = GEPOps.size(); i != e; ++i)
232  RemoveInstInputs(GEPOps[i], InstInputs);
233 
234  return AddAsInput(V);
235  }
236 
237  // Scan to see if we have this GEP available.
238  Value *APHIOp = GEPOps[0];
239  for (User *U : APHIOp->users()) {
240  if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(U))
241  if (GEPI->getType() == GEP->getType() &&
242  GEPI->getNumOperands() == GEPOps.size() &&
243  GEPI->getParent()->getParent() == CurBB->getParent() &&
244  (!DT || DT->dominates(GEPI->getParent(), PredBB))) {
245  if (std::equal(GEPOps.begin(), GEPOps.end(), GEPI->op_begin()))
246  return GEPI;
247  }
248  }
249  return nullptr;
250  }
251 
252  // Handle add with a constant RHS.
253  if (Inst->getOpcode() == Instruction::Add &&
254  isa<ConstantInt>(Inst->getOperand(1))) {
255  // PHI translate the LHS.
256  Constant *RHS = cast<ConstantInt>(Inst->getOperand(1));
257  bool isNSW = cast<BinaryOperator>(Inst)->hasNoSignedWrap();
258  bool isNUW = cast<BinaryOperator>(Inst)->hasNoUnsignedWrap();
259 
260  Value *LHS = PHITranslateSubExpr(Inst->getOperand(0), CurBB, PredBB, DT);
261  if (!LHS) return nullptr;
262 
263  // If the PHI translated LHS is an add of a constant, fold the immediates.
264  if (BinaryOperator *BOp = dyn_cast<BinaryOperator>(LHS))
265  if (BOp->getOpcode() == Instruction::Add)
266  if (ConstantInt *CI = dyn_cast<ConstantInt>(BOp->getOperand(1))) {
267  LHS = BOp->getOperand(0);
268  RHS = ConstantExpr::getAdd(RHS, CI);
269  isNSW = isNUW = false;
270 
271  // If the old 'LHS' was an input, add the new 'LHS' as an input.
272  if (is_contained(InstInputs, BOp)) {
273  RemoveInstInputs(BOp, InstInputs);
274  AddAsInput(LHS);
275  }
276  }
277 
278  // See if the add simplifies away.
279  if (Value *Res = SimplifyAddInst(LHS, RHS, isNSW, isNUW, {DL, TLI, DT, AC})) {
280  // If we simplified the operands, the LHS is no longer an input, but Res
281  // is.
282  RemoveInstInputs(LHS, InstInputs);
283  return AddAsInput(Res);
284  }
285 
286  // If we didn't modify the add, just return it.
287  if (LHS == Inst->getOperand(0) && RHS == Inst->getOperand(1))
288  return Inst;
289 
290  // Otherwise, see if we have this add available somewhere.
291  for (User *U : LHS->users()) {
292  if (BinaryOperator *BO = dyn_cast<BinaryOperator>(U))
293  if (BO->getOpcode() == Instruction::Add &&
294  BO->getOperand(0) == LHS && BO->getOperand(1) == RHS &&
295  BO->getParent()->getParent() == CurBB->getParent() &&
296  (!DT || DT->dominates(BO->getParent(), PredBB)))
297  return BO;
298  }
299 
300  return nullptr;
301  }
302 
303  // Otherwise, we failed.
304  return nullptr;
305 }
306 
307 
308 /// PHITranslateValue - PHI translate the current address up the CFG from
309 /// CurBB to Pred, updating our state to reflect any needed changes. If
310 /// 'MustDominate' is true, the translated value must dominate
311 /// PredBB. This returns true on failure and sets Addr to null.
313  const DominatorTree *DT,
314  bool MustDominate) {
315  assert(DT || !MustDominate);
316  assert(Verify() && "Invalid PHITransAddr!");
317  if (DT && DT->isReachableFromEntry(PredBB))
318  Addr =
319  PHITranslateSubExpr(Addr, CurBB, PredBB, MustDominate ? DT : nullptr);
320  else
321  Addr = nullptr;
322  assert(Verify() && "Invalid PHITransAddr!");
323 
324  if (MustDominate)
325  // Make sure the value is live in the predecessor.
326  if (Instruction *Inst = dyn_cast_or_null<Instruction>(Addr))
327  if (!DT->dominates(Inst->getParent(), PredBB))
328  Addr = nullptr;
329 
330  return Addr == nullptr;
331 }
332 
333 /// PHITranslateWithInsertion - PHI translate this value into the specified
334 /// predecessor block, inserting a computation of the value if it is
335 /// unavailable.
336 ///
337 /// All newly created instructions are added to the NewInsts list. This
338 /// returns null on failure.
339 ///
342  const DominatorTree &DT,
343  SmallVectorImpl<Instruction*> &NewInsts) {
344  unsigned NISize = NewInsts.size();
345 
346  // Attempt to PHI translate with insertion.
347  Addr = InsertPHITranslatedSubExpr(Addr, CurBB, PredBB, DT, NewInsts);
348 
349  // If successful, return the new value.
350  if (Addr) return Addr;
351 
352  // If not, destroy any intermediate instructions inserted.
353  while (NewInsts.size() != NISize)
354  NewInsts.pop_back_val()->eraseFromParent();
355  return nullptr;
356 }
357 
358 
359 /// InsertPHITranslatedPointer - Insert a computation of the PHI translated
360 /// version of 'V' for the edge PredBB->CurBB into the end of the PredBB
361 /// block. All newly created instructions are added to the NewInsts list.
362 /// This returns null on failure.
363 ///
364 Value *PHITransAddr::
365 InsertPHITranslatedSubExpr(Value *InVal, BasicBlock *CurBB,
366  BasicBlock *PredBB, const DominatorTree &DT,
367  SmallVectorImpl<Instruction*> &NewInsts) {
368  // See if we have a version of this value already available and dominating
369  // PredBB. If so, there is no need to insert a new instance of it.
370  PHITransAddr Tmp(InVal, DL, AC);
371  if (!Tmp.PHITranslateValue(CurBB, PredBB, &DT, /*MustDominate=*/true))
372  return Tmp.getAddr();
373 
374  // We don't need to PHI translate values which aren't instructions.
375  auto *Inst = dyn_cast<Instruction>(InVal);
376  if (!Inst)
377  return nullptr;
378 
379  // Handle cast of PHI translatable value.
380  if (CastInst *Cast = dyn_cast<CastInst>(Inst)) {
381  if (!isSafeToSpeculativelyExecute(Cast)) return nullptr;
382  Value *OpVal = InsertPHITranslatedSubExpr(Cast->getOperand(0),
383  CurBB, PredBB, DT, NewInsts);
384  if (!OpVal) return nullptr;
385 
386  // Otherwise insert a cast at the end of PredBB.
387  CastInst *New = CastInst::Create(Cast->getOpcode(), OpVal, InVal->getType(),
388  InVal->getName() + ".phi.trans.insert",
389  PredBB->getTerminator());
390  New->setDebugLoc(Inst->getDebugLoc());
391  NewInsts.push_back(New);
392  return New;
393  }
394 
395  // Handle getelementptr with at least one PHI operand.
396  if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Inst)) {
397  SmallVector<Value*, 8> GEPOps;
398  BasicBlock *CurBB = GEP->getParent();
399  for (unsigned i = 0, e = GEP->getNumOperands(); i != e; ++i) {
400  Value *OpVal = InsertPHITranslatedSubExpr(GEP->getOperand(i),
401  CurBB, PredBB, DT, NewInsts);
402  if (!OpVal) return nullptr;
403  GEPOps.push_back(OpVal);
404  }
405 
407  GEP->getSourceElementType(), GEPOps[0], makeArrayRef(GEPOps).slice(1),
408  InVal->getName() + ".phi.trans.insert", PredBB->getTerminator());
409  Result->setDebugLoc(Inst->getDebugLoc());
410  Result->setIsInBounds(GEP->isInBounds());
411  NewInsts.push_back(Result);
412  return Result;
413  }
414 
415 #if 0
416  // FIXME: This code works, but it is unclear that we actually want to insert
417  // a big chain of computation in order to make a value available in a block.
418  // This needs to be evaluated carefully to consider its cost trade offs.
419 
420  // Handle add with a constant RHS.
421  if (Inst->getOpcode() == Instruction::Add &&
422  isa<ConstantInt>(Inst->getOperand(1))) {
423  // PHI translate the LHS.
424  Value *OpVal = InsertPHITranslatedSubExpr(Inst->getOperand(0),
425  CurBB, PredBB, DT, NewInsts);
426  if (OpVal == 0) return 0;
427 
428  BinaryOperator *Res = BinaryOperator::CreateAdd(OpVal, Inst->getOperand(1),
429  InVal->getName()+".phi.trans.insert",
430  PredBB->getTerminator());
431  Res->setHasNoSignedWrap(cast<BinaryOperator>(Inst)->hasNoSignedWrap());
432  Res->setHasNoUnsignedWrap(cast<BinaryOperator>(Inst)->hasNoUnsignedWrap());
433  NewInsts.push_back(Res);
434  return Res;
435  }
436 #endif
437 
438  return nullptr;
439 }
uint64_t CallInst * C
SymbolTableList< Instruction >::iterator eraseFromParent()
This method unlinks &#39;this&#39; from the containing basic block and deletes it.
Definition: Instruction.cpp:69
void push_back(const T &Elt)
Definition: SmallVector.h:212
raw_ostream & errs()
This returns a reference to a raw_ostream for standard error.
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
#define LLVM_DUMP_METHOD
Mark debug helper function definitions like dump() that should not be stripped from debug builds...
Definition: Compiler.h:449
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:136
static GetElementPtrInst * Create(Type *PointeeType, Value *Ptr, ArrayRef< Value *> IdxList, const Twine &NameStr="", Instruction *InsertBefore=nullptr)
Definition: Instructions.h:863
static void RemoveInstInputs(Value *V, SmallVectorImpl< Instruction *> &InstInputs)
Hexagon Common GEP
bool isReachableFromEntry(const Use &U) const
Provide an overload for a Use.
Definition: Dominators.cpp:290
static Constant * getAdd(Constant *C1, Constant *C2, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2115
This is the base class for all instructions that perform data casts.
Definition: InstrTypes.h:560
ArrayRef< T > makeArrayRef(const T &OneElt)
Construct an ArrayRef from a single element.
Definition: ArrayRef.h:451
Value * SimplifyGEPInst(Type *SrcTy, ArrayRef< Value *> Ops, const SimplifyQuery &Q)
Given operands for a GetElementPtrInst, fold the result or return null.
void setIsInBounds(bool b=true)
Set or clear the inbounds flag on this GEP instruction.
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:42
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
unsigned getOpcode() const
Returns a member of one of the enums like Instruction::Add.
Definition: Instruction.h:125
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree...
Definition: Dominators.h:140
static BinaryOperator * CreateAdd(Value *S1, Value *S2, const Twine &Name, Instruction *InsertBefore, Value *FlagsOp)
Value * getOperand(unsigned i) const
Definition: User.h:154
an instruction for type-safe pointer arithmetic to access elements of arrays and structs ...
Definition: Instructions.h:837
void setDebugLoc(DebugLoc Loc)
Set the debug location information for this instruction.
Definition: Instruction.h:281
LLVM Basic Block Representation.
Definition: BasicBlock.h:59
PHITransAddr - An address value which tracks and handles phi translation.
Definition: PHITransAddr.h:36
This is an important base class in LLVM.
Definition: Constant.h:42
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:116
This file contains the declarations for the subclasses of Constant, which represent the different fla...
void dump() const
Value * SimplifyAddInst(Value *LHS, Value *RHS, bool isNSW, bool isNUW, const SimplifyQuery &Q)
Given operands for an Add, fold the result or return null.
iterator erase(const_iterator CI)
Definition: SmallVector.h:449
auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range))
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Definition: STLExtras.h:834
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void setHasNoSignedWrap(bool b=true)
Set or clear the nsw flag on this instruction, which must be an operator which supports this flag...
unsigned getNumOperands() const
Definition: User.h:176
Value * PHITranslateWithInsertion(BasicBlock *CurBB, BasicBlock *PredBB, const DominatorTree &DT, SmallVectorImpl< Instruction *> &NewInsts)
PHITranslateWithInsertion - PHI translate this value into the specified predecessor block...
This is the shared class of boolean and integer constants.
Definition: Constants.h:84
bool PHITranslateValue(BasicBlock *CurBB, BasicBlock *PredBB, const DominatorTree *DT, bool MustDominate)
PHITranslateValue - PHI translate the current address up the CFG from CurBB to Pred, updating our state to reflect any needed changes.
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:864
bool dominates(const Instruction *Def, const Use &U) const
Return true if Def dominates a use in User.
Definition: Dominators.cpp:239
LLVM_NODISCARD T pop_back_val()
Definition: SmallVector.h:385
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
typename SuperClass::iterator iterator
Definition: SmallVector.h:328
iterator_range< user_iterator > users()
Definition: Value.h:401
static Constant * getCast(unsigned ops, Constant *C, Type *Ty, bool OnlyIfReduced=false)
Convenience function for getting a Cast operation.
Definition: Constants.cpp:1435
static bool CanPHITrans(Instruction *Inst)
static CastInst * Create(Instruction::CastOps, Value *S, Type *Ty, const Twine &Name="", Instruction *InsertBefore=nullptr)
Provides a way to construct any of the CastInst subclasses using an opcode instead of the subclass&#39;s ...
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:120
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:220
const Function * getParent() const
Return the enclosing method, or null if none.
Definition: BasicBlock.h:108
bool Verify() const
Verify - Check internal consistency of this data structure.
#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
bool IsPotentiallyPHITranslatable() const
IsPotentiallyPHITranslatable - If this needs PHI translation, return true if we have some hope of doi...
Value * getAddr() const
Definition: PHITransAddr.h:60
static bool VerifySubExpr(Value *Expr, SmallVectorImpl< Instruction *> &InstInputs)
void setHasNoUnsignedWrap(bool b=true)
Set or clear the nsw flag on this instruction, which must be an operator which supports this flag...
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bool isSafeToSpeculativelyExecute(const Value *V, const Instruction *CtxI=nullptr, const DominatorTree *DT=nullptr)
Return true if the instruction does not have any effects besides calculating the result and does not ...
static bool isInput(const StringSet<> &Prefixes, StringRef Arg)
Definition: OptTable.cpp:170
LLVM Value Representation.
Definition: Value.h:73
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
const BasicBlock * getParent() const
Definition: Instruction.h:66
bool is_contained(R &&Range, const E &Element)
Wrapper function around std::find to detect if an element exists in a container.
Definition: STLExtras.h:867