LLVM  6.0.0svn
MemoryBuiltins.cpp
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1 //===- MemoryBuiltins.cpp - Identify calls to memory builtins -------------===//
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 family of functions identifies calls to builtin functions that allocate
11 // or free memory.
12 //
13 //===----------------------------------------------------------------------===//
14 
16 #include "llvm/ADT/APInt.h"
17 #include "llvm/ADT/None.h"
18 #include "llvm/ADT/Optional.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/ADT/StringRef.h"
25 #include "llvm/IR/Argument.h"
26 #include "llvm/IR/Attributes.h"
27 #include "llvm/IR/Constants.h"
28 #include "llvm/IR/DataLayout.h"
29 #include "llvm/IR/DerivedTypes.h"
30 #include "llvm/IR/Function.h"
31 #include "llvm/IR/GlobalAlias.h"
32 #include "llvm/IR/GlobalVariable.h"
33 #include "llvm/IR/Instruction.h"
34 #include "llvm/IR/Instructions.h"
35 #include "llvm/IR/IntrinsicInst.h"
36 #include "llvm/IR/Operator.h"
37 #include "llvm/IR/Type.h"
38 #include "llvm/IR/Value.h"
39 #include "llvm/Support/Casting.h"
40 #include "llvm/Support/Debug.h"
44 #include <cassert>
45 #include <cstdint>
46 #include <iterator>
47 #include <utility>
48 
49 using namespace llvm;
50 
51 #define DEBUG_TYPE "memory-builtins"
52 
53 enum AllocType : uint8_t {
54  OpNewLike = 1<<0, // allocates; never returns null
55  MallocLike = 1<<1 | OpNewLike, // allocates; may return null
56  CallocLike = 1<<2, // allocates + bzero
57  ReallocLike = 1<<3, // reallocates
58  StrDupLike = 1<<4,
62 };
63 
64 struct AllocFnsTy {
66  unsigned NumParams;
67  // First and Second size parameters (or -1 if unused)
68  int FstParam, SndParam;
69 };
70 
71 // FIXME: certain users need more information. E.g., SimplifyLibCalls needs to
72 // know which functions are nounwind, noalias, nocapture parameters, etc.
73 static const std::pair<LibFunc, AllocFnsTy> AllocationFnData[] = {
74  {LibFunc_malloc, {MallocLike, 1, 0, -1}},
75  {LibFunc_valloc, {MallocLike, 1, 0, -1}},
76  {LibFunc_Znwj, {OpNewLike, 1, 0, -1}}, // new(unsigned int)
77  {LibFunc_ZnwjRKSt9nothrow_t, {MallocLike, 2, 0, -1}}, // new(unsigned int, nothrow)
78  {LibFunc_Znwm, {OpNewLike, 1, 0, -1}}, // new(unsigned long)
79  {LibFunc_ZnwmRKSt9nothrow_t, {MallocLike, 2, 0, -1}}, // new(unsigned long, nothrow)
80  {LibFunc_Znaj, {OpNewLike, 1, 0, -1}}, // new[](unsigned int)
81  {LibFunc_ZnajRKSt9nothrow_t, {MallocLike, 2, 0, -1}}, // new[](unsigned int, nothrow)
82  {LibFunc_Znam, {OpNewLike, 1, 0, -1}}, // new[](unsigned long)
83  {LibFunc_ZnamRKSt9nothrow_t, {MallocLike, 2, 0, -1}}, // new[](unsigned long, nothrow)
84  {LibFunc_msvc_new_int, {OpNewLike, 1, 0, -1}}, // new(unsigned int)
85  {LibFunc_msvc_new_int_nothrow, {MallocLike, 2, 0, -1}}, // new(unsigned int, nothrow)
86  {LibFunc_msvc_new_longlong, {OpNewLike, 1, 0, -1}}, // new(unsigned long long)
87  {LibFunc_msvc_new_longlong_nothrow, {MallocLike, 2, 0, -1}}, // new(unsigned long long, nothrow)
88  {LibFunc_msvc_new_array_int, {OpNewLike, 1, 0, -1}}, // new[](unsigned int)
89  {LibFunc_msvc_new_array_int_nothrow, {MallocLike, 2, 0, -1}}, // new[](unsigned int, nothrow)
90  {LibFunc_msvc_new_array_longlong, {OpNewLike, 1, 0, -1}}, // new[](unsigned long long)
91  {LibFunc_msvc_new_array_longlong_nothrow, {MallocLike, 2, 0, -1}}, // new[](unsigned long long, nothrow)
92  {LibFunc_calloc, {CallocLike, 2, 0, 1}},
93  {LibFunc_realloc, {ReallocLike, 2, 1, -1}},
94  {LibFunc_reallocf, {ReallocLike, 2, 1, -1}},
95  {LibFunc_strdup, {StrDupLike, 1, -1, -1}},
96  {LibFunc_strndup, {StrDupLike, 2, 1, -1}}
97  // TODO: Handle "int posix_memalign(void **, size_t, size_t)"
98 };
99 
100 static const Function *getCalledFunction(const Value *V, bool LookThroughBitCast,
101  bool &IsNoBuiltin) {
102  // Don't care about intrinsics in this case.
103  if (isa<IntrinsicInst>(V))
104  return nullptr;
105 
106  if (LookThroughBitCast)
107  V = V->stripPointerCasts();
108 
109  ImmutableCallSite CS(V);
110  if (!CS.getInstruction())
111  return nullptr;
112 
113  IsNoBuiltin = CS.isNoBuiltin();
114 
115  const Function *Callee = CS.getCalledFunction();
116  if (!Callee || !Callee->isDeclaration())
117  return nullptr;
118  return Callee;
119 }
120 
121 /// Returns the allocation data for the given value if it's either a call to a
122 /// known allocation function, or a call to a function with the allocsize
123 /// attribute.
126  const TargetLibraryInfo *TLI) {
127  // Make sure that the function is available.
128  StringRef FnName = Callee->getName();
129  LibFunc TLIFn;
130  if (!TLI || !TLI->getLibFunc(FnName, TLIFn) || !TLI->has(TLIFn))
131  return None;
132 
133  const auto *Iter = find_if(
134  AllocationFnData, [TLIFn](const std::pair<LibFunc, AllocFnsTy> &P) {
135  return P.first == TLIFn;
136  });
137 
138  if (Iter == std::end(AllocationFnData))
139  return None;
140 
141  const AllocFnsTy *FnData = &Iter->second;
142  if ((FnData->AllocTy & AllocTy) != FnData->AllocTy)
143  return None;
144 
145  // Check function prototype.
146  int FstParam = FnData->FstParam;
147  int SndParam = FnData->SndParam;
148  FunctionType *FTy = Callee->getFunctionType();
149 
150  if (FTy->getReturnType() == Type::getInt8PtrTy(FTy->getContext()) &&
151  FTy->getNumParams() == FnData->NumParams &&
152  (FstParam < 0 ||
153  (FTy->getParamType(FstParam)->isIntegerTy(32) ||
154  FTy->getParamType(FstParam)->isIntegerTy(64))) &&
155  (SndParam < 0 ||
156  FTy->getParamType(SndParam)->isIntegerTy(32) ||
157  FTy->getParamType(SndParam)->isIntegerTy(64)))
158  return *FnData;
159  return None;
160 }
161 
163  const TargetLibraryInfo *TLI,
164  bool LookThroughBitCast = false) {
165  bool IsNoBuiltinCall;
166  if (const Function *Callee =
167  getCalledFunction(V, LookThroughBitCast, IsNoBuiltinCall))
168  if (!IsNoBuiltinCall)
169  return getAllocationDataForFunction(Callee, AllocTy, TLI);
170  return None;
171 }
172 
174  const TargetLibraryInfo *TLI) {
175  bool IsNoBuiltinCall;
176  const Function *Callee =
177  getCalledFunction(V, /*LookThroughBitCast=*/false, IsNoBuiltinCall);
178  if (!Callee)
179  return None;
180 
181  // Prefer to use existing information over allocsize. This will give us an
182  // accurate AllocTy.
183  if (!IsNoBuiltinCall)
186  return Data;
187 
188  Attribute Attr = Callee->getFnAttribute(Attribute::AllocSize);
189  if (Attr == Attribute())
190  return None;
191 
192  std::pair<unsigned, Optional<unsigned>> Args = Attr.getAllocSizeArgs();
193 
194  AllocFnsTy Result;
195  // Because allocsize only tells us how many bytes are allocated, we're not
196  // really allowed to assume anything, so we use MallocLike.
197  Result.AllocTy = MallocLike;
198  Result.NumParams = Callee->getNumOperands();
199  Result.FstParam = Args.first;
200  Result.SndParam = Args.second.getValueOr(-1);
201  return Result;
202 }
203 
204 static bool hasNoAliasAttr(const Value *V, bool LookThroughBitCast) {
205  ImmutableCallSite CS(LookThroughBitCast ? V->stripPointerCasts() : V);
206  return CS && CS.hasRetAttr(Attribute::NoAlias);
207 }
208 
209 /// \brief Tests if a value is a call or invoke to a library function that
210 /// allocates or reallocates memory (either malloc, calloc, realloc, or strdup
211 /// like).
212 bool llvm::isAllocationFn(const Value *V, const TargetLibraryInfo *TLI,
213  bool LookThroughBitCast) {
214  return getAllocationData(V, AnyAlloc, TLI, LookThroughBitCast).hasValue();
215 }
216 
217 /// \brief Tests if a value is a call or invoke to a function that returns a
218 /// NoAlias pointer (including malloc/calloc/realloc/strdup-like functions).
219 bool llvm::isNoAliasFn(const Value *V, const TargetLibraryInfo *TLI,
220  bool LookThroughBitCast) {
221  // it's safe to consider realloc as noalias since accessing the original
222  // pointer is undefined behavior
223  return isAllocationFn(V, TLI, LookThroughBitCast) ||
224  hasNoAliasAttr(V, LookThroughBitCast);
225 }
226 
227 /// \brief Tests if a value is a call or invoke to a library function that
228 /// allocates uninitialized memory (such as malloc).
229 bool llvm::isMallocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
230  bool LookThroughBitCast) {
231  return getAllocationData(V, MallocLike, TLI, LookThroughBitCast).hasValue();
232 }
233 
234 /// \brief Tests if a value is a call or invoke to a library function that
235 /// allocates zero-filled memory (such as calloc).
236 bool llvm::isCallocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
237  bool LookThroughBitCast) {
238  return getAllocationData(V, CallocLike, TLI, LookThroughBitCast).hasValue();
239 }
240 
241 /// \brief Tests if a value is a call or invoke to a library function that
242 /// allocates memory similiar to malloc or calloc.
244  bool LookThroughBitCast) {
245  return getAllocationData(V, MallocOrCallocLike, TLI,
246  LookThroughBitCast).hasValue();
247 }
248 
249 /// \brief Tests if a value is a call or invoke to a library function that
250 /// allocates memory (either malloc, calloc, or strdup like).
251 bool llvm::isAllocLikeFn(const Value *V, const TargetLibraryInfo *TLI,
252  bool LookThroughBitCast) {
253  return getAllocationData(V, AllocLike, TLI, LookThroughBitCast).hasValue();
254 }
255 
256 /// extractMallocCall - Returns the corresponding CallInst if the instruction
257 /// is a malloc call. Since CallInst::CreateMalloc() only creates calls, we
258 /// ignore InvokeInst here.
260  const TargetLibraryInfo *TLI) {
261  return isMallocLikeFn(I, TLI) ? dyn_cast<CallInst>(I) : nullptr;
262 }
263 
264 static Value *computeArraySize(const CallInst *CI, const DataLayout &DL,
265  const TargetLibraryInfo *TLI,
266  bool LookThroughSExt = false) {
267  if (!CI)
268  return nullptr;
269 
270  // The size of the malloc's result type must be known to determine array size.
271  Type *T = getMallocAllocatedType(CI, TLI);
272  if (!T || !T->isSized())
273  return nullptr;
274 
275  unsigned ElementSize = DL.getTypeAllocSize(T);
276  if (StructType *ST = dyn_cast<StructType>(T))
277  ElementSize = DL.getStructLayout(ST)->getSizeInBytes();
278 
279  // If malloc call's arg can be determined to be a multiple of ElementSize,
280  // return the multiple. Otherwise, return NULL.
281  Value *MallocArg = CI->getArgOperand(0);
282  Value *Multiple = nullptr;
283  if (ComputeMultiple(MallocArg, ElementSize, Multiple, LookThroughSExt))
284  return Multiple;
285 
286  return nullptr;
287 }
288 
289 /// getMallocType - Returns the PointerType resulting from the malloc call.
290 /// The PointerType depends on the number of bitcast uses of the malloc call:
291 /// 0: PointerType is the calls' return type.
292 /// 1: PointerType is the bitcast's result type.
293 /// >1: Unique PointerType cannot be determined, return NULL.
295  const TargetLibraryInfo *TLI) {
296  assert(isMallocLikeFn(CI, TLI) && "getMallocType and not malloc call");
297 
298  PointerType *MallocType = nullptr;
299  unsigned NumOfBitCastUses = 0;
300 
301  // Determine if CallInst has a bitcast use.
302  for (Value::const_user_iterator UI = CI->user_begin(), E = CI->user_end();
303  UI != E;)
304  if (const BitCastInst *BCI = dyn_cast<BitCastInst>(*UI++)) {
305  MallocType = cast<PointerType>(BCI->getDestTy());
306  NumOfBitCastUses++;
307  }
308 
309  // Malloc call has 1 bitcast use, so type is the bitcast's destination type.
310  if (NumOfBitCastUses == 1)
311  return MallocType;
312 
313  // Malloc call was not bitcast, so type is the malloc function's return type.
314  if (NumOfBitCastUses == 0)
315  return cast<PointerType>(CI->getType());
316 
317  // Type could not be determined.
318  return nullptr;
319 }
320 
321 /// getMallocAllocatedType - Returns the Type allocated by malloc call.
322 /// The Type depends on the number of bitcast uses of the malloc call:
323 /// 0: PointerType is the malloc calls' return type.
324 /// 1: PointerType is the bitcast's result type.
325 /// >1: Unique PointerType cannot be determined, return NULL.
327  const TargetLibraryInfo *TLI) {
328  PointerType *PT = getMallocType(CI, TLI);
329  return PT ? PT->getElementType() : nullptr;
330 }
331 
332 /// getMallocArraySize - Returns the array size of a malloc call. If the
333 /// argument passed to malloc is a multiple of the size of the malloced type,
334 /// then return that multiple. For non-array mallocs, the multiple is
335 /// constant 1. Otherwise, return NULL for mallocs whose array size cannot be
336 /// determined.
338  const TargetLibraryInfo *TLI,
339  bool LookThroughSExt) {
340  assert(isMallocLikeFn(CI, TLI) && "getMallocArraySize and not malloc call");
341  return computeArraySize(CI, DL, TLI, LookThroughSExt);
342 }
343 
344 /// extractCallocCall - Returns the corresponding CallInst if the instruction
345 /// is a calloc call.
347  const TargetLibraryInfo *TLI) {
348  return isCallocLikeFn(I, TLI) ? cast<CallInst>(I) : nullptr;
349 }
350 
351 /// isFreeCall - Returns non-null if the value is a call to the builtin free()
352 const CallInst *llvm::isFreeCall(const Value *I, const TargetLibraryInfo *TLI) {
353  const CallInst *CI = dyn_cast<CallInst>(I);
354  if (!CI || isa<IntrinsicInst>(CI))
355  return nullptr;
357  if (Callee == nullptr)
358  return nullptr;
359 
360  StringRef FnName = Callee->getName();
361  LibFunc TLIFn;
362  if (!TLI || !TLI->getLibFunc(FnName, TLIFn) || !TLI->has(TLIFn))
363  return nullptr;
364 
365  unsigned ExpectedNumParams;
366  if (TLIFn == LibFunc_free ||
367  TLIFn == LibFunc_ZdlPv || // operator delete(void*)
368  TLIFn == LibFunc_ZdaPv || // operator delete[](void*)
369  TLIFn == LibFunc_msvc_delete_ptr32 || // operator delete(void*)
370  TLIFn == LibFunc_msvc_delete_ptr64 || // operator delete(void*)
371  TLIFn == LibFunc_msvc_delete_array_ptr32 || // operator delete[](void*)
372  TLIFn == LibFunc_msvc_delete_array_ptr64) // operator delete[](void*)
373  ExpectedNumParams = 1;
374  else if (TLIFn == LibFunc_ZdlPvj || // delete(void*, uint)
375  TLIFn == LibFunc_ZdlPvm || // delete(void*, ulong)
376  TLIFn == LibFunc_ZdlPvRKSt9nothrow_t || // delete(void*, nothrow)
377  TLIFn == LibFunc_ZdaPvj || // delete[](void*, uint)
378  TLIFn == LibFunc_ZdaPvm || // delete[](void*, ulong)
379  TLIFn == LibFunc_ZdaPvRKSt9nothrow_t || // delete[](void*, nothrow)
380  TLIFn == LibFunc_msvc_delete_ptr32_int || // delete(void*, uint)
381  TLIFn == LibFunc_msvc_delete_ptr64_longlong || // delete(void*, ulonglong)
382  TLIFn == LibFunc_msvc_delete_ptr32_nothrow || // delete(void*, nothrow)
383  TLIFn == LibFunc_msvc_delete_ptr64_nothrow || // delete(void*, nothrow)
384  TLIFn == LibFunc_msvc_delete_array_ptr32_int || // delete[](void*, uint)
385  TLIFn == LibFunc_msvc_delete_array_ptr64_longlong || // delete[](void*, ulonglong)
386  TLIFn == LibFunc_msvc_delete_array_ptr32_nothrow || // delete[](void*, nothrow)
387  TLIFn == LibFunc_msvc_delete_array_ptr64_nothrow) // delete[](void*, nothrow)
388  ExpectedNumParams = 2;
389  else
390  return nullptr;
391 
392  // Check free prototype.
393  // FIXME: workaround for PR5130, this will be obsolete when a nobuiltin
394  // attribute will exist.
395  FunctionType *FTy = Callee->getFunctionType();
396  if (!FTy->getReturnType()->isVoidTy())
397  return nullptr;
398  if (FTy->getNumParams() != ExpectedNumParams)
399  return nullptr;
400  if (FTy->getParamType(0) != Type::getInt8PtrTy(Callee->getContext()))
401  return nullptr;
402 
403  return CI;
404 }
405 
406 //===----------------------------------------------------------------------===//
407 // Utility functions to compute size of objects.
408 //
410  if (Data.second.isNegative() || Data.first.ult(Data.second))
411  return APInt(Data.first.getBitWidth(), 0);
412  return Data.first - Data.second;
413 }
414 
415 /// \brief Compute the size of the object pointed by Ptr. Returns true and the
416 /// object size in Size if successful, and false otherwise.
417 /// If RoundToAlign is true, then Size is rounded up to the alignment of
418 /// allocas, byval arguments, and global variables.
419 bool llvm::getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout &DL,
420  const TargetLibraryInfo *TLI, ObjectSizeOpts Opts) {
421  ObjectSizeOffsetVisitor Visitor(DL, TLI, Ptr->getContext(), Opts);
422  SizeOffsetType Data = Visitor.compute(const_cast<Value*>(Ptr));
423  if (!Visitor.bothKnown(Data))
424  return false;
425 
426  Size = getSizeWithOverflow(Data).getZExtValue();
427  return true;
428 }
429 
431  const DataLayout &DL,
432  const TargetLibraryInfo *TLI,
433  bool MustSucceed) {
434  assert(ObjectSize->getIntrinsicID() == Intrinsic::objectsize &&
435  "ObjectSize must be a call to llvm.objectsize!");
436 
437  bool MaxVal = cast<ConstantInt>(ObjectSize->getArgOperand(1))->isZero();
438  ObjectSizeOpts EvalOptions;
439  // Unless we have to fold this to something, try to be as accurate as
440  // possible.
441  if (MustSucceed)
442  EvalOptions.EvalMode =
444  else
446 
447  EvalOptions.NullIsUnknownSize =
448  cast<ConstantInt>(ObjectSize->getArgOperand(2))->isOne();
449 
450  // FIXME: Does it make sense to just return a failure value if the size won't
451  // fit in the output and `!MustSucceed`?
452  uint64_t Size;
453  auto *ResultType = cast<IntegerType>(ObjectSize->getType());
454  if (getObjectSize(ObjectSize->getArgOperand(0), Size, DL, TLI, EvalOptions) &&
455  isUIntN(ResultType->getBitWidth(), Size))
456  return ConstantInt::get(ResultType, Size);
457 
458  if (!MustSucceed)
459  return nullptr;
460 
461  return ConstantInt::get(ResultType, MaxVal ? -1ULL : 0);
462 }
463 
464 STATISTIC(ObjectVisitorArgument,
465  "Number of arguments with unsolved size and offset");
466 STATISTIC(ObjectVisitorLoad,
467  "Number of load instructions with unsolved size and offset");
468 
469 APInt ObjectSizeOffsetVisitor::align(APInt Size, uint64_t Align) {
470  if (Options.RoundToAlign && Align)
471  return APInt(IntTyBits, alignTo(Size.getZExtValue(), Align));
472  return Size;
473 }
474 
476  const TargetLibraryInfo *TLI,
478  ObjectSizeOpts Options)
479  : DL(DL), TLI(TLI), Options(Options) {
480  // Pointer size must be rechecked for each object visited since it could have
481  // a different address space.
482 }
483 
485  IntTyBits = DL.getPointerTypeSizeInBits(V->getType());
486  Zero = APInt::getNullValue(IntTyBits);
487 
488  V = V->stripPointerCasts();
489  if (Instruction *I = dyn_cast<Instruction>(V)) {
490  // If we have already seen this instruction, bail out. Cycles can happen in
491  // unreachable code after constant propagation.
492  if (!SeenInsts.insert(I).second)
493  return unknown();
494 
495  if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
496  return visitGEPOperator(*GEP);
497  return visit(*I);
498  }
499  if (Argument *A = dyn_cast<Argument>(V))
500  return visitArgument(*A);
501  if (ConstantPointerNull *P = dyn_cast<ConstantPointerNull>(V))
502  return visitConstantPointerNull(*P);
503  if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V))
504  return visitGlobalAlias(*GA);
505  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
506  return visitGlobalVariable(*GV);
507  if (UndefValue *UV = dyn_cast<UndefValue>(V))
508  return visitUndefValue(*UV);
509  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
510  if (CE->getOpcode() == Instruction::IntToPtr)
511  return unknown(); // clueless
512  if (CE->getOpcode() == Instruction::GetElementPtr)
513  return visitGEPOperator(cast<GEPOperator>(*CE));
514  }
515 
516  DEBUG(dbgs() << "ObjectSizeOffsetVisitor::compute() unhandled value: " << *V
517  << '\n');
518  return unknown();
519 }
520 
521 /// When we're compiling N-bit code, and the user uses parameters that are
522 /// greater than N bits (e.g. uint64_t on a 32-bit build), we can run into
523 /// trouble with APInt size issues. This function handles resizing + overflow
524 /// checks for us. Check and zext or trunc \p I depending on IntTyBits and
525 /// I's value.
526 bool ObjectSizeOffsetVisitor::CheckedZextOrTrunc(APInt &I) {
527  // More bits than we can handle. Checking the bit width isn't necessary, but
528  // it's faster than checking active bits, and should give `false` in the
529  // vast majority of cases.
530  if (I.getBitWidth() > IntTyBits && I.getActiveBits() > IntTyBits)
531  return false;
532  if (I.getBitWidth() != IntTyBits)
533  I = I.zextOrTrunc(IntTyBits);
534  return true;
535 }
536 
538  if (!I.getAllocatedType()->isSized())
539  return unknown();
540 
541  APInt Size(IntTyBits, DL.getTypeAllocSize(I.getAllocatedType()));
542  if (!I.isArrayAllocation())
543  return std::make_pair(align(Size, I.getAlignment()), Zero);
544 
545  Value *ArraySize = I.getArraySize();
546  if (const ConstantInt *C = dyn_cast<ConstantInt>(ArraySize)) {
547  APInt NumElems = C->getValue();
548  if (!CheckedZextOrTrunc(NumElems))
549  return unknown();
550 
551  bool Overflow;
552  Size = Size.umul_ov(NumElems, Overflow);
553  return Overflow ? unknown() : std::make_pair(align(Size, I.getAlignment()),
554  Zero);
555  }
556  return unknown();
557 }
558 
560  // No interprocedural analysis is done at the moment.
561  if (!A.hasByValOrInAllocaAttr()) {
562  ++ObjectVisitorArgument;
563  return unknown();
564  }
565  PointerType *PT = cast<PointerType>(A.getType());
566  APInt Size(IntTyBits, DL.getTypeAllocSize(PT->getElementType()));
567  return std::make_pair(align(Size, A.getParamAlignment()), Zero);
568 }
569 
572  if (!FnData)
573  return unknown();
574 
575  // Handle strdup-like functions separately.
576  if (FnData->AllocTy == StrDupLike) {
577  APInt Size(IntTyBits, GetStringLength(CS.getArgument(0)));
578  if (!Size)
579  return unknown();
580 
581  // Strndup limits strlen.
582  if (FnData->FstParam > 0) {
583  ConstantInt *Arg =
585  if (!Arg)
586  return unknown();
587 
588  APInt MaxSize = Arg->getValue().zextOrSelf(IntTyBits);
589  if (Size.ugt(MaxSize))
590  Size = MaxSize + 1;
591  }
592  return std::make_pair(Size, Zero);
593  }
594 
596  if (!Arg)
597  return unknown();
598 
599  APInt Size = Arg->getValue();
600  if (!CheckedZextOrTrunc(Size))
601  return unknown();
602 
603  // Size is determined by just 1 parameter.
604  if (FnData->SndParam < 0)
605  return std::make_pair(Size, Zero);
606 
607  Arg = dyn_cast<ConstantInt>(CS.getArgument(FnData->SndParam));
608  if (!Arg)
609  return unknown();
610 
611  APInt NumElems = Arg->getValue();
612  if (!CheckedZextOrTrunc(NumElems))
613  return unknown();
614 
615  bool Overflow;
616  Size = Size.umul_ov(NumElems, Overflow);
617  return Overflow ? unknown() : std::make_pair(Size, Zero);
618 
619  // TODO: handle more standard functions (+ wchar cousins):
620  // - strdup / strndup
621  // - strcpy / strncpy
622  // - strcat / strncat
623  // - memcpy / memmove
624  // - strcat / strncat
625  // - memset
626 }
627 
630  if (Options.NullIsUnknownSize && CPN.getType()->getAddressSpace() == 0)
631  return unknown();
632  return std::make_pair(Zero, Zero);
633 }
634 
637  return unknown();
638 }
639 
642  // Easy cases were already folded by previous passes.
643  return unknown();
644 }
645 
647  SizeOffsetType PtrData = compute(GEP.getPointerOperand());
648  APInt Offset(IntTyBits, 0);
649  if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(DL, Offset))
650  return unknown();
651 
652  return std::make_pair(PtrData.first, PtrData.second + Offset);
653 }
654 
656  if (GA.isInterposable())
657  return unknown();
658  return compute(GA.getAliasee());
659 }
660 
662  if (!GV.hasDefinitiveInitializer())
663  return unknown();
664 
665  APInt Size(IntTyBits, DL.getTypeAllocSize(GV.getType()->getElementType()));
666  return std::make_pair(align(Size, GV.getAlignment()), Zero);
667 }
668 
670  // clueless
671  return unknown();
672 }
673 
675  ++ObjectVisitorLoad;
676  return unknown();
677 }
678 
680  // too complex to analyze statically.
681  return unknown();
682 }
683 
685  SizeOffsetType TrueSide = compute(I.getTrueValue());
686  SizeOffsetType FalseSide = compute(I.getFalseValue());
687  if (bothKnown(TrueSide) && bothKnown(FalseSide)) {
688  if (TrueSide == FalseSide) {
689  return TrueSide;
690  }
691 
692  APInt TrueResult = getSizeWithOverflow(TrueSide);
693  APInt FalseResult = getSizeWithOverflow(FalseSide);
694 
695  if (TrueResult == FalseResult) {
696  return TrueSide;
697  }
698  if (Options.EvalMode == ObjectSizeOpts::Mode::Min) {
699  if (TrueResult.slt(FalseResult))
700  return TrueSide;
701  return FalseSide;
702  }
703  if (Options.EvalMode == ObjectSizeOpts::Mode::Max) {
704  if (TrueResult.sgt(FalseResult))
705  return TrueSide;
706  return FalseSide;
707  }
708  }
709  return unknown();
710 }
711 
713  return std::make_pair(Zero, Zero);
714 }
715 
717  DEBUG(dbgs() << "ObjectSizeOffsetVisitor unknown instruction:" << I << '\n');
718  return unknown();
719 }
720 
722  const DataLayout &DL, const TargetLibraryInfo *TLI, LLVMContext &Context,
723  bool RoundToAlign)
724  : DL(DL), TLI(TLI), Context(Context), Builder(Context, TargetFolder(DL)),
725  RoundToAlign(RoundToAlign) {
726  // IntTy and Zero must be set for each compute() since the address space may
727  // be different for later objects.
728 }
729 
731  // XXX - Are vectors of pointers possible here?
732  IntTy = cast<IntegerType>(DL.getIntPtrType(V->getType()));
733  Zero = ConstantInt::get(IntTy, 0);
734 
735  SizeOffsetEvalType Result = compute_(V);
736 
737  if (!bothKnown(Result)) {
738  // Erase everything that was computed in this iteration from the cache, so
739  // that no dangling references are left behind. We could be a bit smarter if
740  // we kept a dependency graph. It's probably not worth the complexity.
741  for (const Value *SeenVal : SeenVals) {
742  CacheMapTy::iterator CacheIt = CacheMap.find(SeenVal);
743  // non-computable results can be safely cached
744  if (CacheIt != CacheMap.end() && anyKnown(CacheIt->second))
745  CacheMap.erase(CacheIt);
746  }
747  }
748 
749  SeenVals.clear();
750  return Result;
751 }
752 
753 SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute_(Value *V) {
754  ObjectSizeOpts ObjSizeOptions;
755  ObjSizeOptions.RoundToAlign = RoundToAlign;
756 
757  ObjectSizeOffsetVisitor Visitor(DL, TLI, Context, ObjSizeOptions);
758  SizeOffsetType Const = Visitor.compute(V);
759  if (Visitor.bothKnown(Const))
760  return std::make_pair(ConstantInt::get(Context, Const.first),
761  ConstantInt::get(Context, Const.second));
762 
763  V = V->stripPointerCasts();
764 
765  // Check cache.
766  CacheMapTy::iterator CacheIt = CacheMap.find(V);
767  if (CacheIt != CacheMap.end())
768  return CacheIt->second;
769 
770  // Always generate code immediately before the instruction being
771  // processed, so that the generated code dominates the same BBs.
772  BuilderTy::InsertPointGuard Guard(Builder);
773  if (Instruction *I = dyn_cast<Instruction>(V))
774  Builder.SetInsertPoint(I);
775 
776  // Now compute the size and offset.
777  SizeOffsetEvalType Result;
778 
779  // Record the pointers that were handled in this run, so that they can be
780  // cleaned later if something fails. We also use this set to break cycles that
781  // can occur in dead code.
782  if (!SeenVals.insert(V).second) {
783  Result = unknown();
784  } else if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
785  Result = visitGEPOperator(*GEP);
786  } else if (Instruction *I = dyn_cast<Instruction>(V)) {
787  Result = visit(*I);
788  } else if (isa<Argument>(V) ||
789  (isa<ConstantExpr>(V) &&
790  cast<ConstantExpr>(V)->getOpcode() == Instruction::IntToPtr) ||
791  isa<GlobalAlias>(V) ||
792  isa<GlobalVariable>(V)) {
793  // Ignore values where we cannot do more than ObjectSizeVisitor.
794  Result = unknown();
795  } else {
796  DEBUG(dbgs() << "ObjectSizeOffsetEvaluator::compute() unhandled value: "
797  << *V << '\n');
798  Result = unknown();
799  }
800 
801  // Don't reuse CacheIt since it may be invalid at this point.
802  CacheMap[V] = Result;
803  return Result;
804 }
805 
807  if (!I.getAllocatedType()->isSized())
808  return unknown();
809 
810  // must be a VLA
812  Value *ArraySize = I.getArraySize();
813  Value *Size = ConstantInt::get(ArraySize->getType(),
815  Size = Builder.CreateMul(Size, ArraySize);
816  return std::make_pair(Size, Zero);
817 }
818 
821  if (!FnData)
822  return unknown();
823 
824  // Handle strdup-like functions separately.
825  if (FnData->AllocTy == StrDupLike) {
826  // TODO
827  return unknown();
828  }
829 
830  Value *FirstArg = CS.getArgument(FnData->FstParam);
831  FirstArg = Builder.CreateZExt(FirstArg, IntTy);
832  if (FnData->SndParam < 0)
833  return std::make_pair(FirstArg, Zero);
834 
835  Value *SecondArg = CS.getArgument(FnData->SndParam);
836  SecondArg = Builder.CreateZExt(SecondArg, IntTy);
837  Value *Size = Builder.CreateMul(FirstArg, SecondArg);
838  return std::make_pair(Size, Zero);
839 
840  // TODO: handle more standard functions (+ wchar cousins):
841  // - strdup / strndup
842  // - strcpy / strncpy
843  // - strcat / strncat
844  // - memcpy / memmove
845  // - strcat / strncat
846  // - memset
847 }
848 
851  return unknown();
852 }
853 
856  return unknown();
857 }
858 
861  SizeOffsetEvalType PtrData = compute_(GEP.getPointerOperand());
862  if (!bothKnown(PtrData))
863  return unknown();
864 
865  Value *Offset = EmitGEPOffset(&Builder, DL, &GEP, /*NoAssumptions=*/true);
866  Offset = Builder.CreateAdd(PtrData.second, Offset);
867  return std::make_pair(PtrData.first, Offset);
868 }
869 
871  // clueless
872  return unknown();
873 }
874 
876  return unknown();
877 }
878 
880  // Create 2 PHIs: one for size and another for offset.
881  PHINode *SizePHI = Builder.CreatePHI(IntTy, PHI.getNumIncomingValues());
882  PHINode *OffsetPHI = Builder.CreatePHI(IntTy, PHI.getNumIncomingValues());
883 
884  // Insert right away in the cache to handle recursive PHIs.
885  CacheMap[&PHI] = std::make_pair(SizePHI, OffsetPHI);
886 
887  // Compute offset/size for each PHI incoming pointer.
888  for (unsigned i = 0, e = PHI.getNumIncomingValues(); i != e; ++i) {
890  SizeOffsetEvalType EdgeData = compute_(PHI.getIncomingValue(i));
891 
892  if (!bothKnown(EdgeData)) {
893  OffsetPHI->replaceAllUsesWith(UndefValue::get(IntTy));
894  OffsetPHI->eraseFromParent();
895  SizePHI->replaceAllUsesWith(UndefValue::get(IntTy));
896  SizePHI->eraseFromParent();
897  return unknown();
898  }
899  SizePHI->addIncoming(EdgeData.first, PHI.getIncomingBlock(i));
900  OffsetPHI->addIncoming(EdgeData.second, PHI.getIncomingBlock(i));
901  }
902 
903  Value *Size = SizePHI, *Offset = OffsetPHI, *Tmp;
904  if ((Tmp = SizePHI->hasConstantValue())) {
905  Size = Tmp;
906  SizePHI->replaceAllUsesWith(Size);
907  SizePHI->eraseFromParent();
908  }
909  if ((Tmp = OffsetPHI->hasConstantValue())) {
910  Offset = Tmp;
911  OffsetPHI->replaceAllUsesWith(Offset);
912  OffsetPHI->eraseFromParent();
913  }
914  return std::make_pair(Size, Offset);
915 }
916 
918  SizeOffsetEvalType TrueSide = compute_(I.getTrueValue());
919  SizeOffsetEvalType FalseSide = compute_(I.getFalseValue());
920 
921  if (!bothKnown(TrueSide) || !bothKnown(FalseSide))
922  return unknown();
923  if (TrueSide == FalseSide)
924  return TrueSide;
925 
926  Value *Size = Builder.CreateSelect(I.getCondition(), TrueSide.first,
927  FalseSide.first);
928  Value *Offset = Builder.CreateSelect(I.getCondition(), TrueSide.second,
929  FalseSide.second);
930  return std::make_pair(Size, Offset);
931 }
932 
934  DEBUG(dbgs() << "ObjectSizeOffsetEvaluator unknown instruction:" << I <<'\n');
935  return unknown();
936 }
bool getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout &DL, const TargetLibraryInfo *TLI, ObjectSizeOpts Opts={})
Compute the size of the object pointed by Ptr.
Value * EmitGEPOffset(IRBuilderTy *Builder, const DataLayout &DL, User *GEP, bool NoAssumptions=false)
Given a getelementptr instruction/constantexpr, emit the code necessary to compute the offset from th...
Definition: Local.h:203
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
unsigned getAlignment() const
Definition: GlobalObject.h:59
bool isAllocationFn(const Value *V, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
Tests if a value is a call or invoke to a library function that allocates or reallocates memory (eith...
A parsed version of the target data layout string in and methods for querying it. ...
Definition: DataLayout.h:109
const_iterator end(StringRef path)
Get end iterator over path.
Definition: Path.cpp:243
bool hasDefinitiveInitializer() const
hasDefinitiveInitializer - Whether the global variable has an initializer, and any other instances of...
static const std::pair< LibFunc, AllocFnsTy > AllocationFnData[]
void addIncoming(Value *V, BasicBlock *BB)
Add an incoming value to the end of the PHI list.
This instruction extracts a struct member or array element value from an aggregate value...
uint64_t getZExtValue() const
Get zero extended value.
Definition: APInt.h:1542
This class represents an incoming formal argument to a Function.
Definition: Argument.h:30
LLVMContext & Context
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
Type * getParamType(unsigned i) const
Parameter type accessors.
Definition: DerivedTypes.h:135
bool isSized(SmallPtrSetImpl< Type *> *Visited=nullptr) const
Return true if it makes sense to take the size of this type.
Definition: Type.h:262
unsigned NumParams
const CallInst * extractCallocCall(const Value *I, const TargetLibraryInfo *TLI)
extractCallocCall - Returns the corresponding CallInst if the instruction is a calloc call...
const StructLayout * getStructLayout(StructType *Ty) const
Returns a StructLayout object, indicating the alignment of the struct, its size, and the offsets of i...
Definition: DataLayout.cpp:562
Attribute
Attributes.
Definition: Dwarf.h:105
bool hasByValOrInAllocaAttr() const
Return true if this argument has the byval attribute or inalloca attribute.
Definition: Function.cpp:106
std::pair< Value *, Value * > SizeOffsetEvalType
bool NullIsUnknownSize
If this is true, null pointers in address space 0 will be treated as though they can&#39;t be evaluated...
bool slt(const APInt &RHS) const
Signed less than comparison.
Definition: APInt.h:1183
This class represents a function call, abstracting a target machine&#39;s calling convention.
static Optional< AllocFnsTy > getAllocationDataForFunction(const Function *Callee, AllocType AllocTy, const TargetLibraryInfo *TLI)
Returns the allocation data for the given value if it&#39;s either a call to a known allocation function...
const Value * getTrueValue() const
bool RoundToAlign
Whether to round the result up to the alignment of allocas, byval arguments, and global variables...
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:697
SizeOffsetType visitAllocaInst(AllocaInst &I)
bool isInterposable() const
Return true if this global&#39;s definition can be substituted with an arbitrary definition at link time...
Definition: GlobalValue.h:400
bool sgt(const APInt &RHS) const
Signed greather than comparison.
Definition: APInt.h:1253
AllocType
STATISTIC(NumFunctions, "Total number of functions")
The two locations do not alias at all.
Definition: AliasAnalysis.h:85
uint64_t alignTo(uint64_t Value, uint64_t Align, uint64_t Skew=0)
Returns the next integer (mod 2**64) that is greater than or equal to Value and is a multiple of Alig...
Definition: MathExtras.h:677
An instruction for reading from memory.
Definition: Instructions.h:164
APInt zextOrTrunc(unsigned width) const
Zero extend or truncate to width.
Definition: APInt.cpp:883
SizeOffsetType visitArgument(Argument &A)
Hexagon Common GEP
unsigned getBitWidth() const
Return the number of bits in the APInt.
Definition: APInt.h:1488
bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const
Accumulate the constant address offset of this GEP if possible.
Definition: Operator.cpp:35
LLVMContext & getContext() const
Return the LLVMContext in which this type was uniqued.
Definition: Type.h:130
const CallInst * isFreeCall(const Value *I, const TargetLibraryInfo *TLI)
isFreeCall - Returns non-null if the value is a call to the builtin free()
This class represents the LLVM &#39;select&#39; instruction.
unsigned getAlignment() const
Return the alignment of the memory that is being allocated by the instruction.
Definition: Instructions.h:109
SizeOffsetEvalType visitGEPOperator(GEPOperator &GEP)
SizeOffsetType visitExtractValueInst(ExtractValueInst &I)
SizeOffsetType visitGEPOperator(GEPOperator &GEP)
unsigned getPointerTypeSizeInBits(Type *) const
Layout pointer size, in bits, based on the type.
Definition: DataLayout.cpp:614
&#39;undef&#39; values are things that do not have specified contents.
Definition: Constants.h:1247
static Optional< AllocFnsTy > getAllocationSize(const Value *V, const TargetLibraryInfo *TLI)
Class to represent struct types.
Definition: DerivedTypes.h:201
APInt zextOrSelf(unsigned width) const
Zero extend or truncate to width.
Definition: APInt.cpp:899
bool isIntegerTy() const
True if this is an instance of IntegerType.
Definition: Type.h:197
SizeOffsetEvalType visitCallSite(CallSite CS)
SizeOffsetType visitIntToPtrInst(IntToPtrInst &)
This file contains the simple types necessary to represent the attributes associated with functions a...
InstrTy * getInstruction() const
Definition: CallSite.h:92
Value * CreateAdd(Value *LHS, Value *RHS, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:889
This file implements a class to represent arbitrary precision integral constant values and operations...
ObjectSizeOffsetEvaluator(const DataLayout &DL, const TargetLibraryInfo *TLI, LLVMContext &Context, bool RoundToAlign=false)
unsigned getActiveBits() const
Compute the number of active bits in the value.
Definition: APInt.h:1512
bool isNoAliasFn(const Value *V, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
Tests if a value is a call or invoke to a function that returns a NoAlias pointer (including malloc/c...
Same as Min, except we pick the maximum size of all of the branches.
A constant value that is initialized with an expression using other constant values.
Definition: Constants.h:862
Class to represent function types.
Definition: DerivedTypes.h:103
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
Evaluate all branches of an unknown condition.
bool isNoBuiltin() const
Return true if the call should not be treated as a call to a builtin.
Definition: CallSite.h:428
bool has(LibFunc F) const
Tests whether a library function is available.
This class represents a no-op cast from one type to another.
const APInt & getValue() const
Return the constant as an APInt value reference.
Definition: Constants.h:138
TargetFolder - Create constants with target dependent folding.
Definition: TargetFolder.h:32
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:428
std::pair< unsigned, Optional< unsigned > > getAllocSizeArgs() const
Returns the argument numbers for the allocsize attribute (or pair(0, 0) if not known).
Definition: Attributes.cpp:237
Value * CreateZExt(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1383
uint64_t GetStringLength(const Value *V, unsigned CharSize=8)
If we can compute the length of the string pointed to by the specified pointer, return &#39;len+1&#39;...
SizeOffsetType visitInstruction(Instruction &I)
amdgpu Simplify well known AMD library false Value * Callee
void SetInsertPoint(BasicBlock *TheBB)
This specifies that created instructions should be appended to the end of the specified block...
Definition: IRBuilder.h:128
Class to represent pointers.
Definition: DerivedTypes.h:467
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:146
Value * getMallocArraySize(CallInst *CI, const DataLayout &DL, const TargetLibraryInfo *TLI, bool LookThroughSExt=false)
getMallocArraySize - Returns the array size of a malloc call.
SizeOffsetType visitGlobalVariable(GlobalVariable &GV)
bool isVoidTy() const
Return true if this is &#39;void&#39;.
Definition: Type.h:141
IntegerType * getIntPtrType(LLVMContext &C, unsigned AddressSpace=0) const
Returns an integer type with size at least as big as that of a pointer in the given address space...
Definition: DataLayout.cpp:702
#define P(N)
bool erase(const KeyT &Val)
Definition: DenseMap.h:268
SizeOffsetEvalType visitSelectInst(SelectInst &I)
const_iterator getFirstInsertionPt() const
Returns an iterator to the first instruction in this block that is suitable for inserting a non-PHI i...
Definition: BasicBlock.cpp:200
ConstantInt * lowerObjectSizeCall(IntrinsicInst *ObjectSize, const DataLayout &DL, const TargetLibraryInfo *TLI, bool MustSucceed)
Try to turn a call to .objectsize into an integer value of the given Type.
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:69
const CallInst * extractMallocCall(const Value *I, const TargetLibraryInfo *TLI)
extractMallocCall - Returns the corresponding CallInst if the instruction is a malloc call...
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
constexpr char Args[]
Key for Kernel::Metadata::mArgs.
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Value * CreateSelect(Value *C, Value *True, Value *False, const Twine &Name="", Instruction *MDFrom=nullptr)
Definition: IRBuilder.h:1689
unsigned getNumParams() const
Return the number of fixed parameters this function type requires.
Definition: DerivedTypes.h:139
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:363
static Value * computeArraySize(const CallInst *CI, const DataLayout &DL, const TargetLibraryInfo *TLI, bool LookThroughSExt=false)
static APInt getSizeWithOverflow(const SizeOffsetType &Data)
Value * getPointerOperand()
Definition: Operator.h:420
static bool hasNoAliasAttr(const Value *V, bool LookThroughBitCast)
unsigned getAddressSpace() const
Return the address space of the Pointer type.
Definition: DerivedTypes.h:495
static Optional< AllocFnsTy > getAllocationData(const Value *V, AllocType AllocTy, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
This class represents a cast from an integer to a pointer.
const Value * getCondition() const
LLVMContext & getContext() const
getContext - Return a reference to the LLVMContext associated with this function. ...
Definition: Function.cpp:194
static UndefValue * get(Type *T)
Static factory methods - Return an &#39;undef&#39; object of the specified type.
Definition: Constants.cpp:1320
const Value * stripPointerCasts() const
Strip off pointer casts, all-zero GEPs, and aliases.
Definition: Value.cpp:527
SizeOffsetType visitCallSite(CallSite CS)
const Value * getArraySize() const
Get the number of elements allocated.
Definition: Instructions.h:93
std::pair< APInt, APInt > SizeOffsetType
Value * getIncomingValue(unsigned i) const
Return incoming value number x.
static PointerType * getInt8PtrTy(LLVMContext &C, unsigned AS=0)
Definition: Type.cpp:220
PointerType * getMallocType(const CallInst *CI, const TargetLibraryInfo *TLI)
getMallocType - Returns the PointerType resulting from the malloc call.
Value * CreateMul(Value *LHS, Value *RHS, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:933
Type * getAllocatedType() const
Return the type that is being allocated by the instruction.
Definition: Instructions.h:102
SizeOffsetType visitSelectInst(SelectInst &I)
Intrinsic::ID getIntrinsicID() const
Return the intrinsic ID of this intrinsic.
Definition: IntrinsicInst.h:51
SizeOffsetType visitExtractElementInst(ExtractElementInst &I)
SizeOffsetType visitGlobalAlias(GlobalAlias &GA)
PHINode * CreatePHI(Type *Ty, unsigned NumReservedValues, const Twine &Name="")
Definition: IRBuilder.h:1654
SizeOffsetEvalType visitInstruction(Instruction &I)
Value * hasConstantValue() const
If the specified PHI node always merges together the same value, return the value, otherwise return null.
unsigned getNumOperands() const
Definition: User.h:176
Mode EvalMode
How we want to evaluate this object&#39;s size.
This is the shared class of boolean and integer constants.
Definition: Constants.h:84
ValTy * getArgument(unsigned ArgNo) const
Definition: CallSite.h:186
Evaluate the size and offset of an object pointed to by a Value* statically.
unsigned getParamAlignment() const
If this is a byval or inalloca argument, return its alignment.
Definition: Function.cpp:113
Provides information about what library functions are available for the current target.
SizeOffsetType visitPHINode(PHINode &)
A constant pointer value that points to null.
Definition: Constants.h:530
Type * getReturnType() const
Definition: DerivedTypes.h:124
uint64_t getSizeInBytes() const
Definition: DataLayout.h:501
SizeOffsetType visitUndefValue(UndefValue &)
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:560
unsigned getNumIncomingValues() const
Return the number of incoming edges.
static const Function * getCalledFunction(const Value *V, bool LookThroughBitCast, bool &IsNoBuiltin)
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
SizeOffsetType compute(Value *V)
FunctionType * getFunctionType() const
Returns the FunctionType for me.
Definition: Function.h:145
Class for arbitrary precision integers.
Definition: APInt.h:69
SizeOffsetEvalType visitIntToPtrInst(IntToPtrInst &)
Type * getMallocAllocatedType(const CallInst *CI, const TargetLibraryInfo *TLI)
getMallocAllocatedType - Returns the Type allocated by malloc call.
SizeOffsetEvalType visitPHINode(PHINode &PHI)
bool getLibFunc(StringRef funcName, LibFunc &F) const
Searches for a particular function name.
bool isMallocLikeFn(const Value *V, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
Tests if a value is a call or invoke to a library function that allocates uninitialized memory (such ...
const Value * getFalseValue() const
user_iterator_impl< const User > const_user_iterator
Definition: Value.h:365
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
amdgpu Simplify well known AMD library false Value Value * Arg
Fail to evaluate an unknown condition.
SizeOffsetEvalType compute(Value *V)
uint64_t getTypeAllocSize(Type *Ty) const
Returns the offset in bytes between successive objects of the specified type, including alignment pad...
Definition: DataLayout.h:405
Function * getCalledFunction() const
Return the function called, or null if this is an indirect function invocation.
bool ugt(const APInt &RHS) const
Unsigned greather than comparison.
Definition: APInt.h:1234
static bool isZero(Value *V, const DataLayout &DL, DominatorTree *DT, AssumptionCache *AC)
Definition: Lint.cpp:529
ObjectSizeOffsetVisitor(const DataLayout &DL, const TargetLibraryInfo *TLI, LLVMContext &Context, ObjectSizeOpts Options={})
SizeOffsetEvalType visitLoadInst(LoadInst &I)
bool isMallocOrCallocLikeFn(const Value *V, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
Tests if a value is a call or invoke to a library function that allocates memory similar to malloc or...
Value * getArgOperand(unsigned i) const
getArgOperand/setArgOperand - Return/set the i-th call argument.
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:218
Establish a view to a call site for examination.
Definition: CallSite.h:695
BasicBlock * getIncomingBlock(unsigned i) const
Return incoming basic block number i.
bool isCallocLikeFn(const Value *V, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
Tests if a value is a call or invoke to a library function that allocates zero-filled memory (such as...
#define I(x, y, z)
Definition: MD5.cpp:58
PointerType * getType() const
Specialize the getType() method to always return an PointerType, which reduces the amount of casting ...
Definition: Constants.h:546
bool isAllocLikeFn(const Value *V, const TargetLibraryInfo *TLI, bool LookThroughBitCast=false)
Tests if a value is a call or invoke to a library function that allocates memory (either malloc...
constexpr char Align[]
Key for Kernel::Arg::Metadata::mAlign.
iterator end()
Definition: DenseMap.h:79
bool ComputeMultiple(Value *V, unsigned Base, Value *&Multiple, bool LookThroughSExt=false, unsigned Depth=0)
This function computes the integer multiple of Base that equals V.
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
This instruction extracts a single (scalar) element from a VectorType value.
bool anyKnown(SizeOffsetEvalType SizeOffset)
APInt umul_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1915
bool isDeclaration() const
Return true if the primary definition of this global value is outside of the current translation unit...
Definition: Globals.cpp:200
FunTy * getCalledFunction() const
Return the function being called if this is a direct call, otherwise return null (if it&#39;s an indirect...
Definition: CallSite.h:107
bool isArrayAllocation() const
Return true if there is an allocation size parameter to the allocation instruction that is not 1...
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
user_iterator user_begin()
Definition: Value.h:371
static bool bothKnown(const SizeOffsetType &SizeOffset)
LLVM Value Representation.
Definition: Value.h:73
SizeOffsetEvalType visitExtractElementInst(ExtractElementInst &I)
Attribute getFnAttribute(Attribute::AttrKind Kind) const
Return the attribute for the given attribute kind.
Definition: Function.h:270
AllocType AllocTy
#define DEBUG(X)
Definition: Debug.h:118
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
Various options to control the behavior of getObjectSize.
static APInt getNullValue(unsigned numBits)
Get the &#39;0&#39; value.
Definition: APInt.h:562
auto find_if(R &&Range, UnaryPredicate P) -> decltype(std::begin(Range))
Provide wrappers to std::find_if which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:844
bool isUIntN(unsigned N, uint64_t x)
Checks if an unsigned integer fits into the given (dynamic) bit width.
Definition: MathExtras.h:385
SizeOffsetType visitLoadInst(LoadInst &I)
SizeOffsetEvalType visitAllocaInst(AllocaInst &I)
bool bothKnown(SizeOffsetEvalType SizeOffset)
SizeOffsetType visitConstantPointerNull(ConstantPointerNull &)
SizeOffsetEvalType visitExtractValueInst(ExtractValueInst &I)
Type * getElementType() const
Definition: DerivedTypes.h:486
PointerType * getType() const
Global values are always pointers.
Definition: GlobalValue.h:260
A wrapper class for inspecting calls to intrinsic functions.
Definition: IntrinsicInst.h:44
an instruction to allocate memory on the stack
Definition: Instructions.h:60
user_iterator user_end()
Definition: Value.h:379
const Constant * getAliasee() const
Definition: GlobalAlias.h:78