LLVM  9.0.0svn
InferAddressSpaces.cpp
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1 //===- InferAddressSpace.cpp - --------------------------------------------===//
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 // CUDA C/C++ includes memory space designation as variable type qualifers (such
10 // as __global__ and __shared__). Knowing the space of a memory access allows
11 // CUDA compilers to emit faster PTX loads and stores. For example, a load from
12 // shared memory can be translated to `ld.shared` which is roughly 10% faster
13 // than a generic `ld` on an NVIDIA Tesla K40c.
14 //
15 // Unfortunately, type qualifiers only apply to variable declarations, so CUDA
16 // compilers must infer the memory space of an address expression from
17 // type-qualified variables.
18 //
19 // LLVM IR uses non-zero (so-called) specific address spaces to represent memory
20 // spaces (e.g. addrspace(3) means shared memory). The Clang frontend
21 // places only type-qualified variables in specific address spaces, and then
22 // conservatively `addrspacecast`s each type-qualified variable to addrspace(0)
23 // (so-called the generic address space) for other instructions to use.
24 //
25 // For example, the Clang translates the following CUDA code
26 // __shared__ float a[10];
27 // float v = a[i];
28 // to
29 // %0 = addrspacecast [10 x float] addrspace(3)* @a to [10 x float]*
30 // %1 = gep [10 x float], [10 x float]* %0, i64 0, i64 %i
31 // %v = load float, float* %1 ; emits ld.f32
32 // @a is in addrspace(3) since it's type-qualified, but its use from %1 is
33 // redirected to %0 (the generic version of @a).
34 //
35 // The optimization implemented in this file propagates specific address spaces
36 // from type-qualified variable declarations to its users. For example, it
37 // optimizes the above IR to
38 // %1 = gep [10 x float] addrspace(3)* @a, i64 0, i64 %i
39 // %v = load float addrspace(3)* %1 ; emits ld.shared.f32
40 // propagating the addrspace(3) from @a to %1. As the result, the NVPTX
41 // codegen is able to emit ld.shared.f32 for %v.
42 //
43 // Address space inference works in two steps. First, it uses a data-flow
44 // analysis to infer as many generic pointers as possible to point to only one
45 // specific address space. In the above example, it can prove that %1 only
46 // points to addrspace(3). This algorithm was published in
47 // CUDA: Compiling and optimizing for a GPU platform
48 // Chakrabarti, Grover, Aarts, Kong, Kudlur, Lin, Marathe, Murphy, Wang
49 // ICCS 2012
50 //
51 // Then, address space inference replaces all refinable generic pointers with
52 // equivalent specific pointers.
53 //
54 // The major challenge of implementing this optimization is handling PHINodes,
55 // which may create loops in the data flow graph. This brings two complications.
56 //
57 // First, the data flow analysis in Step 1 needs to be circular. For example,
58 // %generic.input = addrspacecast float addrspace(3)* %input to float*
59 // loop:
60 // %y = phi [ %generic.input, %y2 ]
61 // %y2 = getelementptr %y, 1
62 // %v = load %y2
63 // br ..., label %loop, ...
64 // proving %y specific requires proving both %generic.input and %y2 specific,
65 // but proving %y2 specific circles back to %y. To address this complication,
66 // the data flow analysis operates on a lattice:
67 // uninitialized > specific address spaces > generic.
68 // All address expressions (our implementation only considers phi, bitcast,
69 // addrspacecast, and getelementptr) start with the uninitialized address space.
70 // The monotone transfer function moves the address space of a pointer down a
71 // lattice path from uninitialized to specific and then to generic. A join
72 // operation of two different specific address spaces pushes the expression down
73 // to the generic address space. The analysis completes once it reaches a fixed
74 // point.
75 //
76 // Second, IR rewriting in Step 2 also needs to be circular. For example,
77 // converting %y to addrspace(3) requires the compiler to know the converted
78 // %y2, but converting %y2 needs the converted %y. To address this complication,
79 // we break these cycles using "undef" placeholders. When converting an
80 // instruction `I` to a new address space, if its operand `Op` is not converted
81 // yet, we let `I` temporarily use `undef` and fix all the uses of undef later.
82 // For instance, our algorithm first converts %y to
83 // %y' = phi float addrspace(3)* [ %input, undef ]
84 // Then, it converts %y2 to
85 // %y2' = getelementptr %y', 1
86 // Finally, it fixes the undef in %y' so that
87 // %y' = phi float addrspace(3)* [ %input, %y2' ]
88 //
89 //===----------------------------------------------------------------------===//
90 
91 #include "llvm/ADT/ArrayRef.h"
92 #include "llvm/ADT/DenseMap.h"
93 #include "llvm/ADT/DenseSet.h"
94 #include "llvm/ADT/None.h"
95 #include "llvm/ADT/Optional.h"
96 #include "llvm/ADT/SetVector.h"
97 #include "llvm/ADT/SmallVector.h"
100 #include "llvm/IR/BasicBlock.h"
101 #include "llvm/IR/Constant.h"
102 #include "llvm/IR/Constants.h"
103 #include "llvm/IR/Function.h"
104 #include "llvm/IR/IRBuilder.h"
105 #include "llvm/IR/InstIterator.h"
106 #include "llvm/IR/Instruction.h"
107 #include "llvm/IR/Instructions.h"
108 #include "llvm/IR/IntrinsicInst.h"
109 #include "llvm/IR/Intrinsics.h"
110 #include "llvm/IR/LLVMContext.h"
111 #include "llvm/IR/Operator.h"
112 #include "llvm/IR/Type.h"
113 #include "llvm/IR/Use.h"
114 #include "llvm/IR/User.h"
115 #include "llvm/IR/Value.h"
116 #include "llvm/IR/ValueHandle.h"
117 #include "llvm/Pass.h"
118 #include "llvm/Support/Casting.h"
119 #include "llvm/Support/Compiler.h"
120 #include "llvm/Support/Debug.h"
123 #include "llvm/Transforms/Scalar.h"
125 #include <cassert>
126 #include <iterator>
127 #include <limits>
128 #include <utility>
129 #include <vector>
130 
131 #define DEBUG_TYPE "infer-address-spaces"
132 
133 using namespace llvm;
134 
135 static const unsigned UninitializedAddressSpace =
137 
138 namespace {
139 
140 using ValueToAddrSpaceMapTy = DenseMap<const Value *, unsigned>;
141 
142 /// InferAddressSpaces
143 class InferAddressSpaces : public FunctionPass {
144  /// Target specific address space which uses of should be replaced if
145  /// possible.
146  unsigned FlatAddrSpace;
147 
148 public:
149  static char ID;
150 
151  InferAddressSpaces() : FunctionPass(ID) {}
152 
153  void getAnalysisUsage(AnalysisUsage &AU) const override {
154  AU.setPreservesCFG();
156  }
157 
158  bool runOnFunction(Function &F) override;
159 
160 private:
161  // Returns the new address space of V if updated; otherwise, returns None.
163  updateAddressSpace(const Value &V,
164  const ValueToAddrSpaceMapTy &InferredAddrSpace) const;
165 
166  // Tries to infer the specific address space of each address expression in
167  // Postorder.
168  void inferAddressSpaces(ArrayRef<WeakTrackingVH> Postorder,
169  ValueToAddrSpaceMapTy *InferredAddrSpace) const;
170 
171  bool isSafeToCastConstAddrSpace(Constant *C, unsigned NewAS) const;
172 
173  // Changes the flat address expressions in function F to point to specific
174  // address spaces if InferredAddrSpace says so. Postorder is the postorder of
175  // all flat expressions in the use-def graph of function F.
176  bool rewriteWithNewAddressSpaces(
177  const TargetTransformInfo &TTI, ArrayRef<WeakTrackingVH> Postorder,
178  const ValueToAddrSpaceMapTy &InferredAddrSpace, Function *F) const;
179 
180  void appendsFlatAddressExpressionToPostorderStack(
181  Value *V, std::vector<std::pair<Value *, bool>> &PostorderStack,
182  DenseSet<Value *> &Visited) const;
183 
184  bool rewriteIntrinsicOperands(IntrinsicInst *II,
185  Value *OldV, Value *NewV) const;
186  void collectRewritableIntrinsicOperands(
187  IntrinsicInst *II,
188  std::vector<std::pair<Value *, bool>> &PostorderStack,
189  DenseSet<Value *> &Visited) const;
190 
191  std::vector<WeakTrackingVH> collectFlatAddressExpressions(Function &F) const;
192 
193  Value *cloneValueWithNewAddressSpace(
194  Value *V, unsigned NewAddrSpace,
195  const ValueToValueMapTy &ValueWithNewAddrSpace,
196  SmallVectorImpl<const Use *> *UndefUsesToFix) const;
197  unsigned joinAddressSpaces(unsigned AS1, unsigned AS2) const;
198 };
199 
200 } // end anonymous namespace
201 
202 char InferAddressSpaces::ID = 0;
203 
204 namespace llvm {
205 
207 
208 } // end namespace llvm
209 
210 INITIALIZE_PASS(InferAddressSpaces, DEBUG_TYPE, "Infer address spaces",
211  false, false)
212 
213 // Returns true if V is an address expression.
214 // TODO: Currently, we consider only phi, bitcast, addrspacecast, and
215 // getelementptr operators.
216 static bool isAddressExpression(const Value &V) {
217  if (!isa<Operator>(V))
218  return false;
219 
220  switch (cast<Operator>(V).getOpcode()) {
221  case Instruction::PHI:
222  case Instruction::BitCast:
223  case Instruction::AddrSpaceCast:
224  case Instruction::GetElementPtr:
225  case Instruction::Select:
226  return true;
227  default:
228  return false;
229  }
230 }
231 
232 // Returns the pointer operands of V.
233 //
234 // Precondition: V is an address expression.
236  const Operator &Op = cast<Operator>(V);
237  switch (Op.getOpcode()) {
238  case Instruction::PHI: {
239  auto IncomingValues = cast<PHINode>(Op).incoming_values();
240  return SmallVector<Value *, 2>(IncomingValues.begin(),
241  IncomingValues.end());
242  }
243  case Instruction::BitCast:
244  case Instruction::AddrSpaceCast:
245  case Instruction::GetElementPtr:
246  return {Op.getOperand(0)};
247  case Instruction::Select:
248  return {Op.getOperand(1), Op.getOperand(2)};
249  default:
250  llvm_unreachable("Unexpected instruction type.");
251  }
252 }
253 
254 // TODO: Move logic to TTI?
255 bool InferAddressSpaces::rewriteIntrinsicOperands(IntrinsicInst *II,
256  Value *OldV,
257  Value *NewV) const {
258  Module *M = II->getParent()->getParent()->getParent();
259 
260  switch (II->getIntrinsicID()) {
261  case Intrinsic::amdgcn_atomic_inc:
262  case Intrinsic::amdgcn_atomic_dec:
263  case Intrinsic::amdgcn_ds_fadd:
264  case Intrinsic::amdgcn_ds_fmin:
265  case Intrinsic::amdgcn_ds_fmax: {
267  if (!IsVolatile || !IsVolatile->isZero())
268  return false;
269 
271  }
272  case Intrinsic::objectsize: {
273  Type *DestTy = II->getType();
274  Type *SrcTy = NewV->getType();
275  Function *NewDecl =
276  Intrinsic::getDeclaration(M, II->getIntrinsicID(), {DestTy, SrcTy});
277  II->setArgOperand(0, NewV);
278  II->setCalledFunction(NewDecl);
279  return true;
280  }
281  default:
282  return false;
283  }
284 }
285 
286 // TODO: Move logic to TTI?
287 void InferAddressSpaces::collectRewritableIntrinsicOperands(
288  IntrinsicInst *II, std::vector<std::pair<Value *, bool>> &PostorderStack,
289  DenseSet<Value *> &Visited) const {
290  switch (II->getIntrinsicID()) {
291  case Intrinsic::objectsize:
292  case Intrinsic::amdgcn_atomic_inc:
293  case Intrinsic::amdgcn_atomic_dec:
294  case Intrinsic::amdgcn_ds_fadd:
295  case Intrinsic::amdgcn_ds_fmin:
296  case Intrinsic::amdgcn_ds_fmax:
297  appendsFlatAddressExpressionToPostorderStack(II->getArgOperand(0),
298  PostorderStack, Visited);
299  break;
300  default:
301  break;
302  }
303 }
304 
305 // Returns all flat address expressions in function F. The elements are
306 // If V is an unvisited flat address expression, appends V to PostorderStack
307 // and marks it as visited.
308 void InferAddressSpaces::appendsFlatAddressExpressionToPostorderStack(
309  Value *V, std::vector<std::pair<Value *, bool>> &PostorderStack,
310  DenseSet<Value *> &Visited) const {
311  assert(V->getType()->isPointerTy());
312 
313  // Generic addressing expressions may be hidden in nested constant
314  // expressions.
315  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
316  // TODO: Look in non-address parts, like icmp operands.
317  if (isAddressExpression(*CE) && Visited.insert(CE).second)
318  PostorderStack.push_back(std::make_pair(CE, false));
319 
320  return;
321  }
322 
323  if (isAddressExpression(*V) &&
324  V->getType()->getPointerAddressSpace() == FlatAddrSpace) {
325  if (Visited.insert(V).second) {
326  PostorderStack.push_back(std::make_pair(V, false));
327 
328  Operator *Op = cast<Operator>(V);
329  for (unsigned I = 0, E = Op->getNumOperands(); I != E; ++I) {
330  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Op->getOperand(I))) {
331  if (isAddressExpression(*CE) && Visited.insert(CE).second)
332  PostorderStack.emplace_back(CE, false);
333  }
334  }
335  }
336  }
337 }
338 
339 // Returns all flat address expressions in function F. The elements are ordered
340 // ordered in postorder.
341 std::vector<WeakTrackingVH>
342 InferAddressSpaces::collectFlatAddressExpressions(Function &F) const {
343  // This function implements a non-recursive postorder traversal of a partial
344  // use-def graph of function F.
345  std::vector<std::pair<Value *, bool>> PostorderStack;
346  // The set of visited expressions.
347  DenseSet<Value *> Visited;
348 
349  auto PushPtrOperand = [&](Value *Ptr) {
350  appendsFlatAddressExpressionToPostorderStack(Ptr, PostorderStack,
351  Visited);
352  };
353 
354  // Look at operations that may be interesting accelerate by moving to a known
355  // address space. We aim at generating after loads and stores, but pure
356  // addressing calculations may also be faster.
357  for (Instruction &I : instructions(F)) {
358  if (auto *GEP = dyn_cast<GetElementPtrInst>(&I)) {
359  if (!GEP->getType()->isVectorTy())
360  PushPtrOperand(GEP->getPointerOperand());
361  } else if (auto *LI = dyn_cast<LoadInst>(&I))
362  PushPtrOperand(LI->getPointerOperand());
363  else if (auto *SI = dyn_cast<StoreInst>(&I))
364  PushPtrOperand(SI->getPointerOperand());
365  else if (auto *RMW = dyn_cast<AtomicRMWInst>(&I))
366  PushPtrOperand(RMW->getPointerOperand());
367  else if (auto *CmpX = dyn_cast<AtomicCmpXchgInst>(&I))
368  PushPtrOperand(CmpX->getPointerOperand());
369  else if (auto *MI = dyn_cast<MemIntrinsic>(&I)) {
370  // For memset/memcpy/memmove, any pointer operand can be replaced.
371  PushPtrOperand(MI->getRawDest());
372 
373  // Handle 2nd operand for memcpy/memmove.
374  if (auto *MTI = dyn_cast<MemTransferInst>(MI))
375  PushPtrOperand(MTI->getRawSource());
376  } else if (auto *II = dyn_cast<IntrinsicInst>(&I))
377  collectRewritableIntrinsicOperands(II, PostorderStack, Visited);
378  else if (ICmpInst *Cmp = dyn_cast<ICmpInst>(&I)) {
379  // FIXME: Handle vectors of pointers
380  if (Cmp->getOperand(0)->getType()->isPointerTy()) {
381  PushPtrOperand(Cmp->getOperand(0));
382  PushPtrOperand(Cmp->getOperand(1));
383  }
384  } else if (auto *ASC = dyn_cast<AddrSpaceCastInst>(&I)) {
385  if (!ASC->getType()->isVectorTy())
386  PushPtrOperand(ASC->getPointerOperand());
387  }
388  }
389 
390  std::vector<WeakTrackingVH> Postorder; // The resultant postorder.
391  while (!PostorderStack.empty()) {
392  Value *TopVal = PostorderStack.back().first;
393  // If the operands of the expression on the top are already explored,
394  // adds that expression to the resultant postorder.
395  if (PostorderStack.back().second) {
396  if (TopVal->getType()->getPointerAddressSpace() == FlatAddrSpace)
397  Postorder.push_back(TopVal);
398  PostorderStack.pop_back();
399  continue;
400  }
401  // Otherwise, adds its operands to the stack and explores them.
402  PostorderStack.back().second = true;
403  for (Value *PtrOperand : getPointerOperands(*TopVal)) {
404  appendsFlatAddressExpressionToPostorderStack(PtrOperand, PostorderStack,
405  Visited);
406  }
407  }
408  return Postorder;
409 }
410 
411 // A helper function for cloneInstructionWithNewAddressSpace. Returns the clone
412 // of OperandUse.get() in the new address space. If the clone is not ready yet,
413 // returns an undef in the new address space as a placeholder.
415  const Use &OperandUse, unsigned NewAddrSpace,
416  const ValueToValueMapTy &ValueWithNewAddrSpace,
417  SmallVectorImpl<const Use *> *UndefUsesToFix) {
418  Value *Operand = OperandUse.get();
419 
420  Type *NewPtrTy =
421  Operand->getType()->getPointerElementType()->getPointerTo(NewAddrSpace);
422 
423  if (Constant *C = dyn_cast<Constant>(Operand))
424  return ConstantExpr::getAddrSpaceCast(C, NewPtrTy);
425 
426  if (Value *NewOperand = ValueWithNewAddrSpace.lookup(Operand))
427  return NewOperand;
428 
429  UndefUsesToFix->push_back(&OperandUse);
430  return UndefValue::get(NewPtrTy);
431 }
432 
433 // Returns a clone of `I` with its operands converted to those specified in
434 // ValueWithNewAddrSpace. Due to potential cycles in the data flow graph, an
435 // operand whose address space needs to be modified might not exist in
436 // ValueWithNewAddrSpace. In that case, uses undef as a placeholder operand and
437 // adds that operand use to UndefUsesToFix so that caller can fix them later.
438 //
439 // Note that we do not necessarily clone `I`, e.g., if it is an addrspacecast
440 // from a pointer whose type already matches. Therefore, this function returns a
441 // Value* instead of an Instruction*.
443  Instruction *I, unsigned NewAddrSpace,
444  const ValueToValueMapTy &ValueWithNewAddrSpace,
445  SmallVectorImpl<const Use *> *UndefUsesToFix) {
446  Type *NewPtrType =
447  I->getType()->getPointerElementType()->getPointerTo(NewAddrSpace);
448 
449  if (I->getOpcode() == Instruction::AddrSpaceCast) {
450  Value *Src = I->getOperand(0);
451  // Because `I` is flat, the source address space must be specific.
452  // Therefore, the inferred address space must be the source space, according
453  // to our algorithm.
454  assert(Src->getType()->getPointerAddressSpace() == NewAddrSpace);
455  if (Src->getType() != NewPtrType)
456  return new BitCastInst(Src, NewPtrType);
457  return Src;
458  }
459 
460  // Computes the converted pointer operands.
461  SmallVector<Value *, 4> NewPointerOperands;
462  for (const Use &OperandUse : I->operands()) {
463  if (!OperandUse.get()->getType()->isPointerTy())
464  NewPointerOperands.push_back(nullptr);
465  else
467  OperandUse, NewAddrSpace, ValueWithNewAddrSpace, UndefUsesToFix));
468  }
469 
470  switch (I->getOpcode()) {
471  case Instruction::BitCast:
472  return new BitCastInst(NewPointerOperands[0], NewPtrType);
473  case Instruction::PHI: {
474  assert(I->getType()->isPointerTy());
475  PHINode *PHI = cast<PHINode>(I);
476  PHINode *NewPHI = PHINode::Create(NewPtrType, PHI->getNumIncomingValues());
477  for (unsigned Index = 0; Index < PHI->getNumIncomingValues(); ++Index) {
478  unsigned OperandNo = PHINode::getOperandNumForIncomingValue(Index);
479  NewPHI->addIncoming(NewPointerOperands[OperandNo],
480  PHI->getIncomingBlock(Index));
481  }
482  return NewPHI;
483  }
484  case Instruction::GetElementPtr: {
485  GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
487  GEP->getSourceElementType(), NewPointerOperands[0],
488  SmallVector<Value *, 4>(GEP->idx_begin(), GEP->idx_end()));
489  NewGEP->setIsInBounds(GEP->isInBounds());
490  return NewGEP;
491  }
492  case Instruction::Select:
493  assert(I->getType()->isPointerTy());
494  return SelectInst::Create(I->getOperand(0), NewPointerOperands[1],
495  NewPointerOperands[2], "", nullptr, I);
496  default:
497  llvm_unreachable("Unexpected opcode");
498  }
499 }
500 
501 // Similar to cloneInstructionWithNewAddressSpace, returns a clone of the
502 // constant expression `CE` with its operands replaced as specified in
503 // ValueWithNewAddrSpace.
505  ConstantExpr *CE, unsigned NewAddrSpace,
506  const ValueToValueMapTy &ValueWithNewAddrSpace) {
507  Type *TargetType =
508  CE->getType()->getPointerElementType()->getPointerTo(NewAddrSpace);
509 
510  if (CE->getOpcode() == Instruction::AddrSpaceCast) {
511  // Because CE is flat, the source address space must be specific.
512  // Therefore, the inferred address space must be the source space according
513  // to our algorithm.
515  NewAddrSpace);
516  return ConstantExpr::getBitCast(CE->getOperand(0), TargetType);
517  }
518 
519  if (CE->getOpcode() == Instruction::BitCast) {
520  if (Value *NewOperand = ValueWithNewAddrSpace.lookup(CE->getOperand(0)))
521  return ConstantExpr::getBitCast(cast<Constant>(NewOperand), TargetType);
522  return ConstantExpr::getAddrSpaceCast(CE, TargetType);
523  }
524 
525  if (CE->getOpcode() == Instruction::Select) {
526  Constant *Src0 = CE->getOperand(1);
527  Constant *Src1 = CE->getOperand(2);
528  if (Src0->getType()->getPointerAddressSpace() ==
529  Src1->getType()->getPointerAddressSpace()) {
530 
532  CE->getOperand(0), ConstantExpr::getAddrSpaceCast(Src0, TargetType),
533  ConstantExpr::getAddrSpaceCast(Src1, TargetType));
534  }
535  }
536 
537  // Computes the operands of the new constant expression.
538  bool IsNew = false;
539  SmallVector<Constant *, 4> NewOperands;
540  for (unsigned Index = 0; Index < CE->getNumOperands(); ++Index) {
541  Constant *Operand = CE->getOperand(Index);
542  // If the address space of `Operand` needs to be modified, the new operand
543  // with the new address space should already be in ValueWithNewAddrSpace
544  // because (1) the constant expressions we consider (i.e. addrspacecast,
545  // bitcast, and getelementptr) do not incur cycles in the data flow graph
546  // and (2) this function is called on constant expressions in postorder.
547  if (Value *NewOperand = ValueWithNewAddrSpace.lookup(Operand)) {
548  IsNew = true;
549  NewOperands.push_back(cast<Constant>(NewOperand));
550  } else {
551  // Otherwise, reuses the old operand.
552  NewOperands.push_back(Operand);
553  }
554  }
555 
556  // If !IsNew, we will replace the Value with itself. However, replaced values
557  // are assumed to wrapped in a addrspace cast later so drop it now.
558  if (!IsNew)
559  return nullptr;
560 
561  if (CE->getOpcode() == Instruction::GetElementPtr) {
562  // Needs to specify the source type while constructing a getelementptr
563  // constant expression.
564  return CE->getWithOperands(
565  NewOperands, TargetType, /*OnlyIfReduced=*/false,
566  NewOperands[0]->getType()->getPointerElementType());
567  }
568 
569  return CE->getWithOperands(NewOperands, TargetType);
570 }
571 
572 // Returns a clone of the value `V`, with its operands replaced as specified in
573 // ValueWithNewAddrSpace. This function is called on every flat address
574 // expression whose address space needs to be modified, in postorder.
575 //
576 // See cloneInstructionWithNewAddressSpace for the meaning of UndefUsesToFix.
577 Value *InferAddressSpaces::cloneValueWithNewAddressSpace(
578  Value *V, unsigned NewAddrSpace,
579  const ValueToValueMapTy &ValueWithNewAddrSpace,
580  SmallVectorImpl<const Use *> *UndefUsesToFix) const {
581  // All values in Postorder are flat address expressions.
582  assert(isAddressExpression(*V) &&
583  V->getType()->getPointerAddressSpace() == FlatAddrSpace);
584 
585  if (Instruction *I = dyn_cast<Instruction>(V)) {
587  I, NewAddrSpace, ValueWithNewAddrSpace, UndefUsesToFix);
588  if (Instruction *NewI = dyn_cast<Instruction>(NewV)) {
589  if (NewI->getParent() == nullptr) {
590  NewI->insertBefore(I);
591  NewI->takeName(I);
592  }
593  }
594  return NewV;
595  }
596 
598  cast<ConstantExpr>(V), NewAddrSpace, ValueWithNewAddrSpace);
599 }
600 
601 // Defines the join operation on the address space lattice (see the file header
602 // comments).
603 unsigned InferAddressSpaces::joinAddressSpaces(unsigned AS1,
604  unsigned AS2) const {
605  if (AS1 == FlatAddrSpace || AS2 == FlatAddrSpace)
606  return FlatAddrSpace;
607 
608  if (AS1 == UninitializedAddressSpace)
609  return AS2;
610  if (AS2 == UninitializedAddressSpace)
611  return AS1;
612 
613  // The join of two different specific address spaces is flat.
614  return (AS1 == AS2) ? AS1 : FlatAddrSpace;
615 }
616 
618  if (skipFunction(F))
619  return false;
620 
621  const TargetTransformInfo &TTI =
622  getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
623  FlatAddrSpace = TTI.getFlatAddressSpace();
624  if (FlatAddrSpace == UninitializedAddressSpace)
625  return false;
626 
627  // Collects all flat address expressions in postorder.
628  std::vector<WeakTrackingVH> Postorder = collectFlatAddressExpressions(F);
629 
630  // Runs a data-flow analysis to refine the address spaces of every expression
631  // in Postorder.
632  ValueToAddrSpaceMapTy InferredAddrSpace;
633  inferAddressSpaces(Postorder, &InferredAddrSpace);
634 
635  // Changes the address spaces of the flat address expressions who are inferred
636  // to point to a specific address space.
637  return rewriteWithNewAddressSpaces(TTI, Postorder, InferredAddrSpace, &F);
638 }
639 
640 // Constants need to be tracked through RAUW to handle cases with nested
641 // constant expressions, so wrap values in WeakTrackingVH.
642 void InferAddressSpaces::inferAddressSpaces(
643  ArrayRef<WeakTrackingVH> Postorder,
644  ValueToAddrSpaceMapTy *InferredAddrSpace) const {
645  SetVector<Value *> Worklist(Postorder.begin(), Postorder.end());
646  // Initially, all expressions are in the uninitialized address space.
647  for (Value *V : Postorder)
648  (*InferredAddrSpace)[V] = UninitializedAddressSpace;
649 
650  while (!Worklist.empty()) {
651  Value *V = Worklist.pop_back_val();
652 
653  // Tries to update the address space of the stack top according to the
654  // address spaces of its operands.
655  LLVM_DEBUG(dbgs() << "Updating the address space of\n " << *V << '\n');
656  Optional<unsigned> NewAS = updateAddressSpace(*V, *InferredAddrSpace);
657  if (!NewAS.hasValue())
658  continue;
659  // If any updates are made, grabs its users to the worklist because
660  // their address spaces can also be possibly updated.
661  LLVM_DEBUG(dbgs() << " to " << NewAS.getValue() << '\n');
662  (*InferredAddrSpace)[V] = NewAS.getValue();
663 
664  for (Value *User : V->users()) {
665  // Skip if User is already in the worklist.
666  if (Worklist.count(User))
667  continue;
668 
669  auto Pos = InferredAddrSpace->find(User);
670  // Our algorithm only updates the address spaces of flat address
671  // expressions, which are those in InferredAddrSpace.
672  if (Pos == InferredAddrSpace->end())
673  continue;
674 
675  // Function updateAddressSpace moves the address space down a lattice
676  // path. Therefore, nothing to do if User is already inferred as flat (the
677  // bottom element in the lattice).
678  if (Pos->second == FlatAddrSpace)
679  continue;
680 
681  Worklist.insert(User);
682  }
683  }
684 }
685 
686 Optional<unsigned> InferAddressSpaces::updateAddressSpace(
687  const Value &V, const ValueToAddrSpaceMapTy &InferredAddrSpace) const {
688  assert(InferredAddrSpace.count(&V));
689 
690  // The new inferred address space equals the join of the address spaces
691  // of all its pointer operands.
692  unsigned NewAS = UninitializedAddressSpace;
693 
694  const Operator &Op = cast<Operator>(V);
695  if (Op.getOpcode() == Instruction::Select) {
696  Value *Src0 = Op.getOperand(1);
697  Value *Src1 = Op.getOperand(2);
698 
699  auto I = InferredAddrSpace.find(Src0);
700  unsigned Src0AS = (I != InferredAddrSpace.end()) ?
701  I->second : Src0->getType()->getPointerAddressSpace();
702 
703  auto J = InferredAddrSpace.find(Src1);
704  unsigned Src1AS = (J != InferredAddrSpace.end()) ?
705  J->second : Src1->getType()->getPointerAddressSpace();
706 
707  auto *C0 = dyn_cast<Constant>(Src0);
708  auto *C1 = dyn_cast<Constant>(Src1);
709 
710  // If one of the inputs is a constant, we may be able to do a constant
711  // addrspacecast of it. Defer inferring the address space until the input
712  // address space is known.
713  if ((C1 && Src0AS == UninitializedAddressSpace) ||
714  (C0 && Src1AS == UninitializedAddressSpace))
715  return None;
716 
717  if (C0 && isSafeToCastConstAddrSpace(C0, Src1AS))
718  NewAS = Src1AS;
719  else if (C1 && isSafeToCastConstAddrSpace(C1, Src0AS))
720  NewAS = Src0AS;
721  else
722  NewAS = joinAddressSpaces(Src0AS, Src1AS);
723  } else {
724  for (Value *PtrOperand : getPointerOperands(V)) {
725  auto I = InferredAddrSpace.find(PtrOperand);
726  unsigned OperandAS = I != InferredAddrSpace.end() ?
727  I->second : PtrOperand->getType()->getPointerAddressSpace();
728 
729  // join(flat, *) = flat. So we can break if NewAS is already flat.
730  NewAS = joinAddressSpaces(NewAS, OperandAS);
731  if (NewAS == FlatAddrSpace)
732  break;
733  }
734  }
735 
736  unsigned OldAS = InferredAddrSpace.lookup(&V);
737  assert(OldAS != FlatAddrSpace);
738  if (OldAS == NewAS)
739  return None;
740  return NewAS;
741 }
742 
743 /// \p returns true if \p U is the pointer operand of a memory instruction with
744 /// a single pointer operand that can have its address space changed by simply
745 /// mutating the use to a new value. If the memory instruction is volatile,
746 /// return true only if the target allows the memory instruction to be volatile
747 /// in the new address space.
749  Use &U, unsigned AddrSpace) {
750  User *Inst = U.getUser();
751  unsigned OpNo = U.getOperandNo();
752  bool VolatileIsAllowed = false;
753  if (auto *I = dyn_cast<Instruction>(Inst))
754  VolatileIsAllowed = TTI.hasVolatileVariant(I, AddrSpace);
755 
756  if (auto *LI = dyn_cast<LoadInst>(Inst))
757  return OpNo == LoadInst::getPointerOperandIndex() &&
758  (VolatileIsAllowed || !LI->isVolatile());
759 
760  if (auto *SI = dyn_cast<StoreInst>(Inst))
761  return OpNo == StoreInst::getPointerOperandIndex() &&
762  (VolatileIsAllowed || !SI->isVolatile());
763 
764  if (auto *RMW = dyn_cast<AtomicRMWInst>(Inst))
765  return OpNo == AtomicRMWInst::getPointerOperandIndex() &&
766  (VolatileIsAllowed || !RMW->isVolatile());
767 
768  if (auto *CmpX = dyn_cast<AtomicCmpXchgInst>(Inst))
770  (VolatileIsAllowed || !CmpX->isVolatile());
771 
772  return false;
773 }
774 
775 /// Update memory intrinsic uses that require more complex processing than
776 /// simple memory instructions. Thse require re-mangling and may have multiple
777 /// pointer operands.
779  Value *NewV) {
780  IRBuilder<> B(MI);
783  MDNode *NoAliasMD = MI->getMetadata(LLVMContext::MD_noalias);
784 
785  if (auto *MSI = dyn_cast<MemSetInst>(MI)) {
786  B.CreateMemSet(NewV, MSI->getValue(),
787  MSI->getLength(), MSI->getDestAlignment(),
788  false, // isVolatile
789  TBAA, ScopeMD, NoAliasMD);
790  } else if (auto *MTI = dyn_cast<MemTransferInst>(MI)) {
791  Value *Src = MTI->getRawSource();
792  Value *Dest = MTI->getRawDest();
793 
794  // Be careful in case this is a self-to-self copy.
795  if (Src == OldV)
796  Src = NewV;
797 
798  if (Dest == OldV)
799  Dest = NewV;
800 
801  if (isa<MemCpyInst>(MTI)) {
802  MDNode *TBAAStruct = MTI->getMetadata(LLVMContext::MD_tbaa_struct);
803  B.CreateMemCpy(Dest, MTI->getDestAlignment(),
804  Src, MTI->getSourceAlignment(),
805  MTI->getLength(),
806  false, // isVolatile
807  TBAA, TBAAStruct, ScopeMD, NoAliasMD);
808  } else {
809  assert(isa<MemMoveInst>(MTI));
810  B.CreateMemMove(Dest, MTI->getDestAlignment(),
811  Src, MTI->getSourceAlignment(),
812  MTI->getLength(),
813  false, // isVolatile
814  TBAA, ScopeMD, NoAliasMD);
815  }
816  } else
817  llvm_unreachable("unhandled MemIntrinsic");
818 
819  MI->eraseFromParent();
820  return true;
821 }
822 
823 // \p returns true if it is OK to change the address space of constant \p C with
824 // a ConstantExpr addrspacecast.
825 bool InferAddressSpaces::isSafeToCastConstAddrSpace(Constant *C, unsigned NewAS) const {
826  assert(NewAS != UninitializedAddressSpace);
827 
828  unsigned SrcAS = C->getType()->getPointerAddressSpace();
829  if (SrcAS == NewAS || isa<UndefValue>(C))
830  return true;
831 
832  // Prevent illegal casts between different non-flat address spaces.
833  if (SrcAS != FlatAddrSpace && NewAS != FlatAddrSpace)
834  return false;
835 
836  if (isa<ConstantPointerNull>(C))
837  return true;
838 
839  if (auto *Op = dyn_cast<Operator>(C)) {
840  // If we already have a constant addrspacecast, it should be safe to cast it
841  // off.
842  if (Op->getOpcode() == Instruction::AddrSpaceCast)
843  return isSafeToCastConstAddrSpace(cast<Constant>(Op->getOperand(0)), NewAS);
844 
845  if (Op->getOpcode() == Instruction::IntToPtr &&
846  Op->getType()->getPointerAddressSpace() == FlatAddrSpace)
847  return true;
848  }
849 
850  return false;
851 }
852 
854  Value::use_iterator End) {
855  User *CurUser = I->getUser();
856  ++I;
857 
858  while (I != End && I->getUser() == CurUser)
859  ++I;
860 
861  return I;
862 }
863 
864 bool InferAddressSpaces::rewriteWithNewAddressSpaces(
865  const TargetTransformInfo &TTI, ArrayRef<WeakTrackingVH> Postorder,
866  const ValueToAddrSpaceMapTy &InferredAddrSpace, Function *F) const {
867  // For each address expression to be modified, creates a clone of it with its
868  // pointer operands converted to the new address space. Since the pointer
869  // operands are converted, the clone is naturally in the new address space by
870  // construction.
871  ValueToValueMapTy ValueWithNewAddrSpace;
872  SmallVector<const Use *, 32> UndefUsesToFix;
873  for (Value* V : Postorder) {
874  unsigned NewAddrSpace = InferredAddrSpace.lookup(V);
875  if (V->getType()->getPointerAddressSpace() != NewAddrSpace) {
876  ValueWithNewAddrSpace[V] = cloneValueWithNewAddressSpace(
877  V, NewAddrSpace, ValueWithNewAddrSpace, &UndefUsesToFix);
878  }
879  }
880 
881  if (ValueWithNewAddrSpace.empty())
882  return false;
883 
884  // Fixes all the undef uses generated by cloneInstructionWithNewAddressSpace.
885  for (const Use *UndefUse : UndefUsesToFix) {
886  User *V = UndefUse->getUser();
887  User *NewV = cast<User>(ValueWithNewAddrSpace.lookup(V));
888  unsigned OperandNo = UndefUse->getOperandNo();
889  assert(isa<UndefValue>(NewV->getOperand(OperandNo)));
890  NewV->setOperand(OperandNo, ValueWithNewAddrSpace.lookup(UndefUse->get()));
891  }
892 
893  SmallVector<Instruction *, 16> DeadInstructions;
894 
895  // Replaces the uses of the old address expressions with the new ones.
896  for (const WeakTrackingVH &WVH : Postorder) {
897  assert(WVH && "value was unexpectedly deleted");
898  Value *V = WVH;
899  Value *NewV = ValueWithNewAddrSpace.lookup(V);
900  if (NewV == nullptr)
901  continue;
902 
903  LLVM_DEBUG(dbgs() << "Replacing the uses of " << *V << "\n with\n "
904  << *NewV << '\n');
905 
906  if (Constant *C = dyn_cast<Constant>(V)) {
907  Constant *Replace = ConstantExpr::getAddrSpaceCast(cast<Constant>(NewV),
908  C->getType());
909  if (C != Replace) {
910  LLVM_DEBUG(dbgs() << "Inserting replacement const cast: " << Replace
911  << ": " << *Replace << '\n');
912  C->replaceAllUsesWith(Replace);
913  V = Replace;
914  }
915  }
916 
917  Value::use_iterator I, E, Next;
918  for (I = V->use_begin(), E = V->use_end(); I != E; ) {
919  Use &U = *I;
920 
921  // Some users may see the same pointer operand in multiple operands. Skip
922  // to the next instruction.
923  I = skipToNextUser(I, E);
924 
926  TTI, U, V->getType()->getPointerAddressSpace())) {
927  // If V is used as the pointer operand of a compatible memory operation,
928  // sets the pointer operand to NewV. This replacement does not change
929  // the element type, so the resultant load/store is still valid.
930  U.set(NewV);
931  continue;
932  }
933 
934  User *CurUser = U.getUser();
935  // Handle more complex cases like intrinsic that need to be remangled.
936  if (auto *MI = dyn_cast<MemIntrinsic>(CurUser)) {
937  if (!MI->isVolatile() && handleMemIntrinsicPtrUse(MI, V, NewV))
938  continue;
939  }
940 
941  if (auto *II = dyn_cast<IntrinsicInst>(CurUser)) {
942  if (rewriteIntrinsicOperands(II, V, NewV))
943  continue;
944  }
945 
946  if (isa<Instruction>(CurUser)) {
947  if (ICmpInst *Cmp = dyn_cast<ICmpInst>(CurUser)) {
948  // If we can infer that both pointers are in the same addrspace,
949  // transform e.g.
950  // %cmp = icmp eq float* %p, %q
951  // into
952  // %cmp = icmp eq float addrspace(3)* %new_p, %new_q
953 
954  unsigned NewAS = NewV->getType()->getPointerAddressSpace();
955  int SrcIdx = U.getOperandNo();
956  int OtherIdx = (SrcIdx == 0) ? 1 : 0;
957  Value *OtherSrc = Cmp->getOperand(OtherIdx);
958 
959  if (Value *OtherNewV = ValueWithNewAddrSpace.lookup(OtherSrc)) {
960  if (OtherNewV->getType()->getPointerAddressSpace() == NewAS) {
961  Cmp->setOperand(OtherIdx, OtherNewV);
962  Cmp->setOperand(SrcIdx, NewV);
963  continue;
964  }
965  }
966 
967  // Even if the type mismatches, we can cast the constant.
968  if (auto *KOtherSrc = dyn_cast<Constant>(OtherSrc)) {
969  if (isSafeToCastConstAddrSpace(KOtherSrc, NewAS)) {
970  Cmp->setOperand(SrcIdx, NewV);
971  Cmp->setOperand(OtherIdx,
972  ConstantExpr::getAddrSpaceCast(KOtherSrc, NewV->getType()));
973  continue;
974  }
975  }
976  }
977 
978  if (AddrSpaceCastInst *ASC = dyn_cast<AddrSpaceCastInst>(CurUser)) {
979  unsigned NewAS = NewV->getType()->getPointerAddressSpace();
980  if (ASC->getDestAddressSpace() == NewAS) {
981  if (ASC->getType()->getPointerElementType() !=
982  NewV->getType()->getPointerElementType()) {
983  NewV = CastInst::Create(Instruction::BitCast, NewV,
984  ASC->getType(), "", ASC);
985  }
986  ASC->replaceAllUsesWith(NewV);
987  DeadInstructions.push_back(ASC);
988  continue;
989  }
990  }
991 
992  // Otherwise, replaces the use with flat(NewV).
993  if (Instruction *I = dyn_cast<Instruction>(V)) {
994  BasicBlock::iterator InsertPos = std::next(I->getIterator());
995  while (isa<PHINode>(InsertPos))
996  ++InsertPos;
997  U.set(new AddrSpaceCastInst(NewV, V->getType(), "", &*InsertPos));
998  } else {
999  U.set(ConstantExpr::getAddrSpaceCast(cast<Constant>(NewV),
1000  V->getType()));
1001  }
1002  }
1003  }
1004 
1005  if (V->use_empty()) {
1006  if (Instruction *I = dyn_cast<Instruction>(V))
1007  DeadInstructions.push_back(I);
1008  }
1009  }
1010 
1011  for (Instruction *I : DeadInstructions)
1013 
1014  return true;
1015 }
1016 
1018  return new InferAddressSpaces();
1019 }
uint64_t CallInst * C
static bool handleMemIntrinsicPtrUse(MemIntrinsic *MI, Value *OldV, Value *NewV)
Update memory intrinsic uses that require more complex processing than simple memory instructions...
SymbolTableList< Instruction >::iterator eraseFromParent()
This method unlinks &#39;this&#39; from the containing basic block and deletes it.
Definition: Instruction.cpp:67
use_iterator use_end()
Definition: Value.h:346
unsigned getOpcode() const
Return the opcode at the root of this constant expression.
Definition: Constants.h:1209
GCNRegPressure max(const GCNRegPressure &P1, const GCNRegPressure &P2)
This class represents lattice values for constants.
Definition: AllocatorList.h:23
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:64
iterator begin() const
Definition: ArrayRef.h:136
constexpr char IsVolatile[]
Key for Kernel::Arg::Metadata::mIsVolatile.
static Constant * getAddrSpaceCast(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1784
static GetElementPtrInst * Create(Type *PointeeType, Value *Ptr, ArrayRef< Value *> IdxList, const Twine &NameStr="", Instruction *InsertBefore=nullptr)
Definition: Instructions.h:899
static SelectInst * Create(Value *C, Value *S1, Value *S2, const Twine &NameStr="", Instruction *InsertBefore=nullptr, Instruction *MDFrom=nullptr)
void setArgOperand(unsigned i, Value *v)
Definition: InstrTypes.h:1160
Metadata node.
Definition: Metadata.h:863
F(f)
unsigned getPointerAddressSpace() const
Get the address space of this pointer or pointer vector type.
Definition: DerivedTypes.h:534
CallInst * CreateMemSet(Value *Ptr, Value *Val, uint64_t Size, unsigned Align, bool isVolatile=false, MDNode *TBAATag=nullptr, MDNode *ScopeTag=nullptr, MDNode *NoAliasTag=nullptr)
Create and insert a memset to the specified pointer and the specified value.
Definition: IRBuilder.h:403
Hexagon Common GEP
This defines the Use class.
Value * get() const
Definition: Use.h:107
Value * getArgOperand(unsigned i) const
Definition: InstrTypes.h:1155
static unsigned getOperandNumForIncomingValue(unsigned i)
AnalysisUsage & addRequired()
This class represents a conversion between pointers from one address space to another.
Type * getPointerElementType() const
Definition: Type.h:375
A Use represents the edge between a Value definition and its users.
Definition: Use.h:55
PointerType * getPointerTo(unsigned AddrSpace=0) const
Return a pointer to the current type.
Definition: Type.cpp:651
static Optional< unsigned > getOpcode(ArrayRef< VPValue *> Values)
Returns the opcode of Values or ~0 if they do not all agree.
Definition: VPlanSLP.cpp:196
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:41
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:742
CallInst * CreateMemMove(Value *Dst, unsigned DstAlign, Value *Src, unsigned SrcAlign, uint64_t Size, bool isVolatile=false, MDNode *TBAATag=nullptr, MDNode *ScopeTag=nullptr, MDNode *NoAliasTag=nullptr)
Create and insert a memmove between the specified pointers.
Definition: IRBuilder.h:493
Type * getSourceElementType() const
Definition: Instructions.h:970
User * getUser() const LLVM_READONLY
Returns the User that contains this Use.
Definition: Use.cpp:40
A constant value that is initialized with an expression using other constant values.
Definition: Constants.h:888
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:244
Value handle that is nullable, but tries to track the Value.
Definition: ValueHandle.h:181
bool isInBounds() const
Determine whether the GEP has the inbounds flag.
void setCalledFunction(Function *Fn)
Sets the function called, including updating the function type.
Definition: InstrTypes.h:1237
const T & getValue() const LLVM_LVALUE_FUNCTION
Definition: Optional.h:255
static Constant * getSelect(Constant *C, Constant *V1, Constant *V2, Type *OnlyIfReducedTy=nullptr)
Select constant expr.
Definition: Constants.cpp:1977
This class represents a no-op cast from one type to another.
op_iterator idx_begin()
Definition: Instructions.h:998
MDNode * getMetadata(unsigned KindID) const
Get the metadata of given kind attached to this Instruction.
Definition: Instruction.h:234
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
unsigned getOpcode() const
Returns a member of one of the enums like Instruction::Add.
Definition: Instruction.h:125
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:429
unsigned getOperandNo() const
Return the operand # of this use in its User.
Definition: Use.cpp:47
bool hasVolatileVariant(Instruction *I, unsigned AddrSpace) const
Return true if the given instruction (assumed to be a memory access instruction) has a volatile varia...
ValueT lookup(const KeyT &Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: ValueMap.h:170
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
Value * getOperand(unsigned i) const
Definition: User.h:169
use_iterator_impl< Use > use_iterator
Definition: Value.h:331
static Constant * getBitCast(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1772
an instruction for type-safe pointer arithmetic to access elements of arrays and structs ...
Definition: Instructions.h:873
static bool runOnFunction(Function &F, bool PostInlining)
static unsigned getPointerOperandIndex()
Definition: Instructions.h:619
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
Wrapper pass for TargetTransformInfo.
void set(Value *Val)
Definition: Value.h:670
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
static unsigned getPointerOperandIndex()
Definition: Instructions.h:414
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This is an important base class in LLVM.
Definition: Constant.h:41
This file contains the declarations for the subclasses of Constant, which represent the different fla...
bool isPointerTy() const
True if this is an instance of PointerType.
Definition: Type.h:223
std::pair< iterator, bool > insert(const ValueT &V)
Definition: DenseSet.h:187
Represent the analysis usage information of a pass.
This instruction compares its operands according to the predicate given to the constructor.
FunctionPass class - This class is used to implement most global optimizations.
Definition: Pass.h:284
op_range operands()
Definition: User.h:237
void initializeInferAddressSpacesPass(PassRegistry &)
bool RecursivelyDeleteTriviallyDeadInstructions(Value *V, const TargetLibraryInfo *TLI=nullptr, MemorySSAUpdater *MSSAU=nullptr)
If the specified value is a trivially dead instruction, delete it.
Definition: Local.cpp:429
static UndefValue * get(Type *T)
Static factory methods - Return an &#39;undef&#39; object of the specified type.
Definition: Constants.cpp:1414
static wasm::ValType getType(const TargetRegisterClass *RC)
Constant * getWithOperands(ArrayRef< Constant *> Ops) const
This returns the current constant expression with the operands replaced with the specified values...
Definition: Constants.h:1229
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Intrinsic::ID getIntrinsicID() const
Return the intrinsic ID of this intrinsic.
Definition: IntrinsicInst.h:50
static Value * cloneConstantExprWithNewAddressSpace(ConstantExpr *CE, unsigned NewAddrSpace, const ValueToValueMapTy &ValueWithNewAddrSpace)
This is the common base class for memset/memcpy/memmove.
#define DEBUG_TYPE
Iterator for intrusive lists based on ilist_node.
unsigned getNumOperands() const
Definition: User.h:191
This is the shared class of boolean and integer constants.
Definition: Constants.h:83
This pass provides access to the codegen interfaces that are needed for IR-level transformations.
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:839
This is a utility class that provides an abstraction for the common functionality between Instruction...
Definition: Operator.h:30
static Value * cloneInstructionWithNewAddressSpace(Instruction *I, unsigned NewAddrSpace, const ValueToValueMapTy &ValueWithNewAddrSpace, SmallVectorImpl< const Use *> *UndefUsesToFix)
iterator end() const
Definition: ArrayRef.h:137
bool empty() const
Definition: ValueMap.h:145
CallInst * CreateMemCpy(Value *Dst, unsigned DstAlign, Value *Src, unsigned SrcAlign, uint64_t Size, bool isVolatile=false, MDNode *TBAATag=nullptr, MDNode *TBAAStructTag=nullptr, MDNode *ScopeTag=nullptr, MDNode *NoAliasTag=nullptr)
Create and insert a memcpy between the specified pointers.
Definition: IRBuilder.h:445
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...
void setPreservesCFG()
This function should be called by the pass, iff they do not:
Definition: Pass.cpp:285
static const unsigned UninitializedAddressSpace
void setOperand(unsigned i, Value *Val)
Definition: User.h:174
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
iterator_range< user_iterator > users()
Definition: Value.h:399
INITIALIZE_PASS(InferAddressSpaces, DEBUG_TYPE, "Infer address spaces", false, false) static bool isAddressExpression(const Value &V)
use_iterator use_begin()
Definition: Value.h:338
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 ...
bool hasValue() const
Definition: Optional.h:259
FunctionPass * createInferAddressSpacesPass()
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
bool isZero() const
This is just a convenience method to make client code smaller for a common code.
Definition: Constants.h:192
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
static unsigned getPointerOperandIndex()
Definition: Instructions.h:813
static unsigned getPointerOperandIndex()
Definition: Instructions.h:286
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
aarch64 promote const
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:565
LLVM Value Representation.
Definition: Value.h:72
unsigned getOpcode() const
Return the opcode for this Instruction or ConstantExpr.
Definition: Operator.h:40
#define LLVM_FALLTHROUGH
LLVM_FALLTHROUGH - Mark fallthrough cases in switch statements.
Definition: Compiler.h:250
static SmallVector< Value *, 2 > getPointerOperands(const Value &V)
static Value::use_iterator skipToNextUser(Value::use_iterator I, Value::use_iterator End)
IRTranslator LLVM IR MI
inst_range instructions(Function *F)
Definition: InstIterator.h:133
PassRegistry - This class manages the registration and intitialization of the pass subsystem as appli...
Definition: PassRegistry.h:38
This pass exposes codegen information to IR-level passes.
#define LLVM_DEBUG(X)
Definition: Debug.h:122
unsigned getFlatAddressSpace() const
Returns the address space ID for a target&#39;s &#39;flat&#39; address space.
static bool isSimplePointerUseValidToReplace(const TargetTransformInfo &TTI, Use &U, unsigned AddrSpace)
returns true if U is the pointer operand of a memory instruction with a single pointer operand that c...
bool use_empty() const
Definition: Value.h:322
A wrapper class for inspecting calls to intrinsic functions.
Definition: IntrinsicInst.h:43
const BasicBlock * getParent() const
Definition: Instruction.h:66
static Value * operandWithNewAddressSpaceOrCreateUndef(const Use &OperandUse, unsigned NewAddrSpace, const ValueToValueMapTy &ValueWithNewAddrSpace, SmallVectorImpl< const Use *> *UndefUsesToFix)