1//===-- Function.cpp - Implement the Global object classes ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the Function class for the IR library.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/IR/Function.h"
15#include "LLVMContextImpl.h"
16#include "SymbolTableListTraitsImpl.h"
17#include "llvm/ADT/DenseMap.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/StringExtras.h"
20#include "llvm/CodeGen/ValueTypes.h"
21#include "llvm/IR/CallSite.h"
22#include "llvm/IR/DerivedTypes.h"
23#include "llvm/IR/InstIterator.h"
24#include "llvm/IR/IntrinsicInst.h"
25#include "llvm/IR/LLVMContext.h"
26#include "llvm/IR/Module.h"
27#include "llvm/Support/ManagedStatic.h"
28#include "llvm/Support/RWMutex.h"
29#include "llvm/Support/StringPool.h"
30#include "llvm/Support/Threading.h"
31using namespace llvm;
32
33// Explicit instantiations of SymbolTableListTraits since some of the methods
34// are not in the public header file...
35template class llvm::SymbolTableListTraits<Argument, Function>;
36template class llvm::SymbolTableListTraits<BasicBlock, Function>;
37
38//===----------------------------------------------------------------------===//
39// Argument Implementation
40//===----------------------------------------------------------------------===//
41
42void Argument::anchor() { }
43
44Argument::Argument(Type *Ty, const Twine &Name, Function *Par)
45  : Value(Ty, Value::ArgumentVal) {
46  Parent = nullptr;
47
48  if (Par)
49    Par->getArgumentList().push_back(this);
50  setName(Name);
51}
52
53void Argument::setParent(Function *parent) {
54  Parent = parent;
55}
56
57/// getArgNo - Return the index of this formal argument in its containing
58/// function.  For example in "void foo(int a, float b)" a is 0 and b is 1.
59unsigned Argument::getArgNo() const {
60  const Function *F = getParent();
61  assert(F && "Argument is not in a function");
62
63  Function::const_arg_iterator AI = F->arg_begin();
64  unsigned ArgIdx = 0;
65  for (; &*AI != this; ++AI)
66    ++ArgIdx;
67
68  return ArgIdx;
69}
70
71/// hasNonNullAttr - Return true if this argument has the nonnull attribute on
72/// it in its containing function. Also returns true if at least one byte is
73/// known to be dereferenceable and the pointer is in addrspace(0).
74bool Argument::hasNonNullAttr() const {
75  if (!getType()->isPointerTy()) return false;
76  if (getParent()->getAttributes().
77        hasAttribute(getArgNo()+1, Attribute::NonNull))
78    return true;
79  else if (getDereferenceableBytes() > 0 &&
80           getType()->getPointerAddressSpace() == 0)
81    return true;
82  return false;
83}
84
85/// hasByValAttr - Return true if this argument has the byval attribute on it
86/// in its containing function.
87bool Argument::hasByValAttr() const {
88  if (!getType()->isPointerTy()) return false;
89  return getParent()->getAttributes().
90    hasAttribute(getArgNo()+1, Attribute::ByVal);
91}
92
93/// \brief Return true if this argument has the inalloca attribute on it in
94/// its containing function.
95bool Argument::hasInAllocaAttr() const {
96  if (!getType()->isPointerTy()) return false;
97  return getParent()->getAttributes().
98    hasAttribute(getArgNo()+1, Attribute::InAlloca);
99}
100
101bool Argument::hasByValOrInAllocaAttr() const {
102  if (!getType()->isPointerTy()) return false;
103  AttributeSet Attrs = getParent()->getAttributes();
104  return Attrs.hasAttribute(getArgNo() + 1, Attribute::ByVal) ||
105         Attrs.hasAttribute(getArgNo() + 1, Attribute::InAlloca);
106}
107
108unsigned Argument::getParamAlignment() const {
109  assert(getType()->isPointerTy() && "Only pointers have alignments");
110  return getParent()->getParamAlignment(getArgNo()+1);
111
112}
113
114uint64_t Argument::getDereferenceableBytes() const {
115  assert(getType()->isPointerTy() &&
116         "Only pointers have dereferenceable bytes");
117  return getParent()->getDereferenceableBytes(getArgNo()+1);
118}
119
120/// hasNestAttr - Return true if this argument has the nest attribute on
121/// it in its containing function.
122bool Argument::hasNestAttr() const {
123  if (!getType()->isPointerTy()) return false;
124  return getParent()->getAttributes().
125    hasAttribute(getArgNo()+1, Attribute::Nest);
126}
127
128/// hasNoAliasAttr - Return true if this argument has the noalias attribute on
129/// it in its containing function.
130bool Argument::hasNoAliasAttr() const {
131  if (!getType()->isPointerTy()) return false;
132  return getParent()->getAttributes().
133    hasAttribute(getArgNo()+1, Attribute::NoAlias);
134}
135
136/// hasNoCaptureAttr - Return true if this argument has the nocapture attribute
137/// on it in its containing function.
138bool Argument::hasNoCaptureAttr() const {
139  if (!getType()->isPointerTy()) return false;
140  return getParent()->getAttributes().
141    hasAttribute(getArgNo()+1, Attribute::NoCapture);
142}
143
144/// hasSRetAttr - Return true if this argument has the sret attribute on
145/// it in its containing function.
146bool Argument::hasStructRetAttr() const {
147  if (!getType()->isPointerTy()) return false;
148  if (this != getParent()->arg_begin())
149    return false; // StructRet param must be first param
150  return getParent()->getAttributes().
151    hasAttribute(1, Attribute::StructRet);
152}
153
154/// hasReturnedAttr - Return true if this argument has the returned attribute on
155/// it in its containing function.
156bool Argument::hasReturnedAttr() const {
157  return getParent()->getAttributes().
158    hasAttribute(getArgNo()+1, Attribute::Returned);
159}
160
161/// hasZExtAttr - Return true if this argument has the zext attribute on it in
162/// its containing function.
163bool Argument::hasZExtAttr() const {
164  return getParent()->getAttributes().
165    hasAttribute(getArgNo()+1, Attribute::ZExt);
166}
167
168/// hasSExtAttr Return true if this argument has the sext attribute on it in its
169/// containing function.
170bool Argument::hasSExtAttr() const {
171  return getParent()->getAttributes().
172    hasAttribute(getArgNo()+1, Attribute::SExt);
173}
174
175/// Return true if this argument has the readonly or readnone attribute on it
176/// in its containing function.
177bool Argument::onlyReadsMemory() const {
178  return getParent()->getAttributes().
179      hasAttribute(getArgNo()+1, Attribute::ReadOnly) ||
180      getParent()->getAttributes().
181      hasAttribute(getArgNo()+1, Attribute::ReadNone);
182}
183
184/// addAttr - Add attributes to an argument.
185void Argument::addAttr(AttributeSet AS) {
186  assert(AS.getNumSlots() <= 1 &&
187         "Trying to add more than one attribute set to an argument!");
188  AttrBuilder B(AS, AS.getSlotIndex(0));
189  getParent()->addAttributes(getArgNo() + 1,
190                             AttributeSet::get(Parent->getContext(),
191                                               getArgNo() + 1, B));
192}
193
194/// removeAttr - Remove attributes from an argument.
195void Argument::removeAttr(AttributeSet AS) {
196  assert(AS.getNumSlots() <= 1 &&
197         "Trying to remove more than one attribute set from an argument!");
198  AttrBuilder B(AS, AS.getSlotIndex(0));
199  getParent()->removeAttributes(getArgNo() + 1,
200                                AttributeSet::get(Parent->getContext(),
201                                                  getArgNo() + 1, B));
202}
203
204//===----------------------------------------------------------------------===//
205// Helper Methods in Function
206//===----------------------------------------------------------------------===//
207
208bool Function::isMaterializable() const {
209  return getGlobalObjectSubClassData();
210}
211
212void Function::setIsMaterializable(bool V) { setGlobalObjectSubClassData(V); }
213
214LLVMContext &Function::getContext() const {
215  return getType()->getContext();
216}
217
218FunctionType *Function::getFunctionType() const { return Ty; }
219
220bool Function::isVarArg() const {
221  return getFunctionType()->isVarArg();
222}
223
224Type *Function::getReturnType() const {
225  return getFunctionType()->getReturnType();
226}
227
228void Function::removeFromParent() {
229  getParent()->getFunctionList().remove(this);
230}
231
232void Function::eraseFromParent() {
233  getParent()->getFunctionList().erase(this);
234}
235
236//===----------------------------------------------------------------------===//
237// Function Implementation
238//===----------------------------------------------------------------------===//
239
240Function::Function(FunctionType *Ty, LinkageTypes Linkage, const Twine &name,
241                   Module *ParentModule)
242    : GlobalObject(PointerType::getUnqual(Ty), Value::FunctionVal, nullptr, 0,
243                   Linkage, name),
244      Ty(Ty) {
245  assert(FunctionType::isValidReturnType(getReturnType()) &&
246         "invalid return type");
247  setIsMaterializable(false);
248  SymTab = new ValueSymbolTable();
249
250  // If the function has arguments, mark them as lazily built.
251  if (Ty->getNumParams())
252    setValueSubclassData(1);   // Set the "has lazy arguments" bit.
253
254  if (ParentModule)
255    ParentModule->getFunctionList().push_back(this);
256
257  // Ensure intrinsics have the right parameter attributes.
258  if (unsigned IID = getIntrinsicID())
259    setAttributes(Intrinsic::getAttributes(getContext(), Intrinsic::ID(IID)));
260
261}
262
263Function::~Function() {
264  dropAllReferences();    // After this it is safe to delete instructions.
265
266  // Delete all of the method arguments and unlink from symbol table...
267  ArgumentList.clear();
268  delete SymTab;
269
270  // Remove the function from the on-the-side GC table.
271  clearGC();
272
273  // Remove the intrinsicID from the Cache.
274  if (getValueName() && isIntrinsic())
275    getContext().pImpl->IntrinsicIDCache.erase(this);
276}
277
278void Function::BuildLazyArguments() const {
279  // Create the arguments vector, all arguments start out unnamed.
280  FunctionType *FT = getFunctionType();
281  for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
282    assert(!FT->getParamType(i)->isVoidTy() &&
283           "Cannot have void typed arguments!");
284    ArgumentList.push_back(new Argument(FT->getParamType(i)));
285  }
286
287  // Clear the lazy arguments bit.
288  unsigned SDC = getSubclassDataFromValue();
289  const_cast<Function*>(this)->setValueSubclassData(SDC &= ~(1<<0));
290}
291
292size_t Function::arg_size() const {
293  return getFunctionType()->getNumParams();
294}
295bool Function::arg_empty() const {
296  return getFunctionType()->getNumParams() == 0;
297}
298
299void Function::setParent(Module *parent) {
300  Parent = parent;
301}
302
303// dropAllReferences() - This function causes all the subinstructions to "let
304// go" of all references that they are maintaining.  This allows one to
305// 'delete' a whole class at a time, even though there may be circular
306// references... first all references are dropped, and all use counts go to
307// zero.  Then everything is deleted for real.  Note that no operations are
308// valid on an object that has "dropped all references", except operator
309// delete.
310//
311void Function::dropAllReferences() {
312  setIsMaterializable(false);
313
314  for (iterator I = begin(), E = end(); I != E; ++I)
315    I->dropAllReferences();
316
317  // Delete all basic blocks. They are now unused, except possibly by
318  // blockaddresses, but BasicBlock's destructor takes care of those.
319  while (!BasicBlocks.empty())
320    BasicBlocks.begin()->eraseFromParent();
321
322  // Prefix and prologue data are stored in a side table.
323  setPrefixData(nullptr);
324  setPrologueData(nullptr);
325}
326
327void Function::addAttribute(unsigned i, Attribute::AttrKind attr) {
328  AttributeSet PAL = getAttributes();
329  PAL = PAL.addAttribute(getContext(), i, attr);
330  setAttributes(PAL);
331}
332
333void Function::addAttributes(unsigned i, AttributeSet attrs) {
334  AttributeSet PAL = getAttributes();
335  PAL = PAL.addAttributes(getContext(), i, attrs);
336  setAttributes(PAL);
337}
338
339void Function::removeAttributes(unsigned i, AttributeSet attrs) {
340  AttributeSet PAL = getAttributes();
341  PAL = PAL.removeAttributes(getContext(), i, attrs);
342  setAttributes(PAL);
343}
344
345void Function::addDereferenceableAttr(unsigned i, uint64_t Bytes) {
346  AttributeSet PAL = getAttributes();
347  PAL = PAL.addDereferenceableAttr(getContext(), i, Bytes);
348  setAttributes(PAL);
349}
350
351void Function::addDereferenceableOrNullAttr(unsigned i, uint64_t Bytes) {
352  AttributeSet PAL = getAttributes();
353  PAL = PAL.addDereferenceableOrNullAttr(getContext(), i, Bytes);
354  setAttributes(PAL);
355}
356
357// Maintain the GC name for each function in an on-the-side table. This saves
358// allocating an additional word in Function for programs which do not use GC
359// (i.e., most programs) at the cost of increased overhead for clients which do
360// use GC.
361static DenseMap<const Function*,PooledStringPtr> *GCNames;
362static StringPool *GCNamePool;
363static ManagedStatic<sys::SmartRWMutex<true> > GCLock;
364
365bool Function::hasGC() const {
366  sys::SmartScopedReader<true> Reader(*GCLock);
367  return GCNames && GCNames->count(this);
368}
369
370const char *Function::getGC() const {
371  assert(hasGC() && "Function has no collector");
372  sys::SmartScopedReader<true> Reader(*GCLock);
373  return *(*GCNames)[this];
374}
375
376void Function::setGC(const char *Str) {
377  sys::SmartScopedWriter<true> Writer(*GCLock);
378  if (!GCNamePool)
379    GCNamePool = new StringPool();
380  if (!GCNames)
381    GCNames = new DenseMap<const Function*,PooledStringPtr>();
382  (*GCNames)[this] = GCNamePool->intern(Str);
383}
384
385void Function::clearGC() {
386  sys::SmartScopedWriter<true> Writer(*GCLock);
387  if (GCNames) {
388    GCNames->erase(this);
389    if (GCNames->empty()) {
390      delete GCNames;
391      GCNames = nullptr;
392      if (GCNamePool->empty()) {
393        delete GCNamePool;
394        GCNamePool = nullptr;
395      }
396    }
397  }
398}
399
400/// copyAttributesFrom - copy all additional attributes (those not needed to
401/// create a Function) from the Function Src to this one.
402void Function::copyAttributesFrom(const GlobalValue *Src) {
403  assert(isa<Function>(Src) && "Expected a Function!");
404  GlobalObject::copyAttributesFrom(Src);
405  const Function *SrcF = cast<Function>(Src);
406  setCallingConv(SrcF->getCallingConv());
407  setAttributes(SrcF->getAttributes());
408  if (SrcF->hasGC())
409    setGC(SrcF->getGC());
410  else
411    clearGC();
412  if (SrcF->hasPrefixData())
413    setPrefixData(SrcF->getPrefixData());
414  else
415    setPrefixData(nullptr);
416  if (SrcF->hasPrologueData())
417    setPrologueData(SrcF->getPrologueData());
418  else
419    setPrologueData(nullptr);
420}
421
422/// getIntrinsicID - This method returns the ID number of the specified
423/// function, or Intrinsic::not_intrinsic if the function is not an
424/// intrinsic, or if the pointer is null.  This value is always defined to be
425/// zero to allow easy checking for whether a function is intrinsic or not.  The
426/// particular intrinsic functions which correspond to this value are defined in
427/// llvm/Intrinsics.h.  Results are cached in the LLVM context, subsequent
428/// requests for the same ID return results much faster from the cache.
429///
430unsigned Function::getIntrinsicID() const {
431  const ValueName *ValName = this->getValueName();
432  if (!ValName || !isIntrinsic())
433    return 0;
434
435  LLVMContextImpl::IntrinsicIDCacheTy &IntrinsicIDCache =
436    getContext().pImpl->IntrinsicIDCache;
437  if (!IntrinsicIDCache.count(this)) {
438    unsigned Id = lookupIntrinsicID();
439    IntrinsicIDCache[this]=Id;
440    return Id;
441  }
442  return IntrinsicIDCache[this];
443}
444
445/// This private method does the actual lookup of an intrinsic ID when the query
446/// could not be answered from the cache.
447unsigned Function::lookupIntrinsicID() const {
448  const ValueName *ValName = this->getValueName();
449  unsigned Len = ValName->getKeyLength();
450  const char *Name = ValName->getKeyData();
451
452#define GET_FUNCTION_RECOGNIZER
453#include "llvm/IR/Intrinsics.gen"
454#undef GET_FUNCTION_RECOGNIZER
455
456  return 0;
457}
458
459/// Returns a stable mangling for the type specified for use in the name
460/// mangling scheme used by 'any' types in intrinsic signatures.  The mangling
461/// of named types is simply their name.  Manglings for unnamed types consist
462/// of a prefix ('p' for pointers, 'a' for arrays, 'f_' for functions)
463/// combined with the mangling of their component types.  A vararg function
464/// type will have a suffix of 'vararg'.  Since function types can contain
465/// other function types, we close a function type mangling with suffix 'f'
466/// which can't be confused with it's prefix.  This ensures we don't have
467/// collisions between two unrelated function types. Otherwise, you might
468/// parse ffXX as f(fXX) or f(fX)X.  (X is a placeholder for any other type.)
469/// Manglings of integers, floats, and vectors ('i', 'f', and 'v' prefix in most
470/// cases) fall back to the MVT codepath, where they could be mangled to
471/// 'x86mmx', for example; matching on derived types is not sufficient to mangle
472/// everything.
473static std::string getMangledTypeStr(Type* Ty) {
474  std::string Result;
475  if (PointerType* PTyp = dyn_cast<PointerType>(Ty)) {
476    Result += "p" + llvm::utostr(PTyp->getAddressSpace()) +
477      getMangledTypeStr(PTyp->getElementType());
478  } else if (ArrayType* ATyp = dyn_cast<ArrayType>(Ty)) {
479    Result += "a" + llvm::utostr(ATyp->getNumElements()) +
480      getMangledTypeStr(ATyp->getElementType());
481  } else if (StructType* STyp = dyn_cast<StructType>(Ty)) {
482    if (!STyp->isLiteral())
483      Result += STyp->getName();
484    else
485      llvm_unreachable("TODO: implement literal types");
486  } else if (FunctionType* FT = dyn_cast<FunctionType>(Ty)) {
487    Result += "f_" + getMangledTypeStr(FT->getReturnType());
488    for (size_t i = 0; i < FT->getNumParams(); i++)
489      Result += getMangledTypeStr(FT->getParamType(i));
490    if (FT->isVarArg())
491      Result += "vararg";
492    // Ensure nested function types are distinguishable.
493    Result += "f";
494  } else if (Ty)
495    Result += EVT::getEVT(Ty).getEVTString();
496  return Result;
497}
498
499std::string Intrinsic::getName(ID id, ArrayRef<Type*> Tys) {
500  assert(id < num_intrinsics && "Invalid intrinsic ID!");
501  static const char * const Table[] = {
502    "not_intrinsic",
503#define GET_INTRINSIC_NAME_TABLE
504#include "llvm/IR/Intrinsics.gen"
505#undef GET_INTRINSIC_NAME_TABLE
506  };
507  if (Tys.empty())
508    return Table[id];
509  std::string Result(Table[id]);
510  for (unsigned i = 0; i < Tys.size(); ++i) {
511    Result += "." + getMangledTypeStr(Tys[i]);
512  }
513  return Result;
514}
515
516
517/// IIT_Info - These are enumerators that describe the entries returned by the
518/// getIntrinsicInfoTableEntries function.
519///
520/// NOTE: This must be kept in synch with the copy in TblGen/IntrinsicEmitter!
521enum IIT_Info {
522  // Common values should be encoded with 0-15.
523  IIT_Done = 0,
524  IIT_I1   = 1,
525  IIT_I8   = 2,
526  IIT_I16  = 3,
527  IIT_I32  = 4,
528  IIT_I64  = 5,
529  IIT_F16  = 6,
530  IIT_F32  = 7,
531  IIT_F64  = 8,
532  IIT_V2   = 9,
533  IIT_V4   = 10,
534  IIT_V8   = 11,
535  IIT_V16  = 12,
536  IIT_V32  = 13,
537  IIT_PTR  = 14,
538  IIT_ARG  = 15,
539
540  // Values from 16+ are only encodable with the inefficient encoding.
541  IIT_V64  = 16,
542  IIT_MMX  = 17,
543  IIT_METADATA = 18,
544  IIT_EMPTYSTRUCT = 19,
545  IIT_STRUCT2 = 20,
546  IIT_STRUCT3 = 21,
547  IIT_STRUCT4 = 22,
548  IIT_STRUCT5 = 23,
549  IIT_EXTEND_ARG = 24,
550  IIT_TRUNC_ARG = 25,
551  IIT_ANYPTR = 26,
552  IIT_V1   = 27,
553  IIT_VARARG = 28,
554  IIT_HALF_VEC_ARG = 29,
555  IIT_SAME_VEC_WIDTH_ARG = 30,
556  IIT_PTR_TO_ARG = 31,
557  IIT_VEC_OF_PTRS_TO_ELT = 32
558};
559
560
561static void DecodeIITType(unsigned &NextElt, ArrayRef<unsigned char> Infos,
562                      SmallVectorImpl<Intrinsic::IITDescriptor> &OutputTable) {
563  IIT_Info Info = IIT_Info(Infos[NextElt++]);
564  unsigned StructElts = 2;
565  using namespace Intrinsic;
566
567  switch (Info) {
568  case IIT_Done:
569    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Void, 0));
570    return;
571  case IIT_VARARG:
572    OutputTable.push_back(IITDescriptor::get(IITDescriptor::VarArg, 0));
573    return;
574  case IIT_MMX:
575    OutputTable.push_back(IITDescriptor::get(IITDescriptor::MMX, 0));
576    return;
577  case IIT_METADATA:
578    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Metadata, 0));
579    return;
580  case IIT_F16:
581    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Half, 0));
582    return;
583  case IIT_F32:
584    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Float, 0));
585    return;
586  case IIT_F64:
587    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Double, 0));
588    return;
589  case IIT_I1:
590    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 1));
591    return;
592  case IIT_I8:
593    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 8));
594    return;
595  case IIT_I16:
596    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer,16));
597    return;
598  case IIT_I32:
599    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 32));
600    return;
601  case IIT_I64:
602    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 64));
603    return;
604  case IIT_V1:
605    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 1));
606    DecodeIITType(NextElt, Infos, OutputTable);
607    return;
608  case IIT_V2:
609    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 2));
610    DecodeIITType(NextElt, Infos, OutputTable);
611    return;
612  case IIT_V4:
613    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 4));
614    DecodeIITType(NextElt, Infos, OutputTable);
615    return;
616  case IIT_V8:
617    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 8));
618    DecodeIITType(NextElt, Infos, OutputTable);
619    return;
620  case IIT_V16:
621    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 16));
622    DecodeIITType(NextElt, Infos, OutputTable);
623    return;
624  case IIT_V32:
625    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 32));
626    DecodeIITType(NextElt, Infos, OutputTable);
627    return;
628  case IIT_V64:
629    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 64));
630    DecodeIITType(NextElt, Infos, OutputTable);
631    return;
632  case IIT_PTR:
633    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer, 0));
634    DecodeIITType(NextElt, Infos, OutputTable);
635    return;
636  case IIT_ANYPTR: {  // [ANYPTR addrspace, subtype]
637    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer,
638                                             Infos[NextElt++]));
639    DecodeIITType(NextElt, Infos, OutputTable);
640    return;
641  }
642  case IIT_ARG: {
643    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
644    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Argument, ArgInfo));
645    return;
646  }
647  case IIT_EXTEND_ARG: {
648    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
649    OutputTable.push_back(IITDescriptor::get(IITDescriptor::ExtendArgument,
650                                             ArgInfo));
651    return;
652  }
653  case IIT_TRUNC_ARG: {
654    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
655    OutputTable.push_back(IITDescriptor::get(IITDescriptor::TruncArgument,
656                                             ArgInfo));
657    return;
658  }
659  case IIT_HALF_VEC_ARG: {
660    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
661    OutputTable.push_back(IITDescriptor::get(IITDescriptor::HalfVecArgument,
662                                             ArgInfo));
663    return;
664  }
665  case IIT_SAME_VEC_WIDTH_ARG: {
666    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
667    OutputTable.push_back(IITDescriptor::get(IITDescriptor::SameVecWidthArgument,
668                                             ArgInfo));
669    return;
670  }
671  case IIT_PTR_TO_ARG: {
672    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
673    OutputTable.push_back(IITDescriptor::get(IITDescriptor::PtrToArgument,
674                                             ArgInfo));
675    return;
676  }
677  case IIT_VEC_OF_PTRS_TO_ELT: {
678    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
679    OutputTable.push_back(IITDescriptor::get(IITDescriptor::VecOfPtrsToElt,
680                                             ArgInfo));
681    return;
682  }
683  case IIT_EMPTYSTRUCT:
684    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct, 0));
685    return;
686  case IIT_STRUCT5: ++StructElts; // FALL THROUGH.
687  case IIT_STRUCT4: ++StructElts; // FALL THROUGH.
688  case IIT_STRUCT3: ++StructElts; // FALL THROUGH.
689  case IIT_STRUCT2: {
690    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct,StructElts));
691
692    for (unsigned i = 0; i != StructElts; ++i)
693      DecodeIITType(NextElt, Infos, OutputTable);
694    return;
695  }
696  }
697  llvm_unreachable("unhandled");
698}
699
700
701#define GET_INTRINSIC_GENERATOR_GLOBAL
702#include "llvm/IR/Intrinsics.gen"
703#undef GET_INTRINSIC_GENERATOR_GLOBAL
704
705void Intrinsic::getIntrinsicInfoTableEntries(ID id,
706                                             SmallVectorImpl<IITDescriptor> &T){
707  // Check to see if the intrinsic's type was expressible by the table.
708  unsigned TableVal = IIT_Table[id-1];
709
710  // Decode the TableVal into an array of IITValues.
711  SmallVector<unsigned char, 8> IITValues;
712  ArrayRef<unsigned char> IITEntries;
713  unsigned NextElt = 0;
714  if ((TableVal >> 31) != 0) {
715    // This is an offset into the IIT_LongEncodingTable.
716    IITEntries = IIT_LongEncodingTable;
717
718    // Strip sentinel bit.
719    NextElt = (TableVal << 1) >> 1;
720  } else {
721    // Decode the TableVal into an array of IITValues.  If the entry was encoded
722    // into a single word in the table itself, decode it now.
723    do {
724      IITValues.push_back(TableVal & 0xF);
725      TableVal >>= 4;
726    } while (TableVal);
727
728    IITEntries = IITValues;
729    NextElt = 0;
730  }
731
732  // Okay, decode the table into the output vector of IITDescriptors.
733  DecodeIITType(NextElt, IITEntries, T);
734  while (NextElt != IITEntries.size() && IITEntries[NextElt] != 0)
735    DecodeIITType(NextElt, IITEntries, T);
736}
737
738
739static Type *DecodeFixedType(ArrayRef<Intrinsic::IITDescriptor> &Infos,
740                             ArrayRef<Type*> Tys, LLVMContext &Context) {
741  using namespace Intrinsic;
742  IITDescriptor D = Infos.front();
743  Infos = Infos.slice(1);
744
745  switch (D.Kind) {
746  case IITDescriptor::Void: return Type::getVoidTy(Context);
747  case IITDescriptor::VarArg: return Type::getVoidTy(Context);
748  case IITDescriptor::MMX: return Type::getX86_MMXTy(Context);
749  case IITDescriptor::Metadata: return Type::getMetadataTy(Context);
750  case IITDescriptor::Half: return Type::getHalfTy(Context);
751  case IITDescriptor::Float: return Type::getFloatTy(Context);
752  case IITDescriptor::Double: return Type::getDoubleTy(Context);
753
754  case IITDescriptor::Integer:
755    return IntegerType::get(Context, D.Integer_Width);
756  case IITDescriptor::Vector:
757    return VectorType::get(DecodeFixedType(Infos, Tys, Context),D.Vector_Width);
758  case IITDescriptor::Pointer:
759    return PointerType::get(DecodeFixedType(Infos, Tys, Context),
760                            D.Pointer_AddressSpace);
761  case IITDescriptor::Struct: {
762    Type *Elts[5];
763    assert(D.Struct_NumElements <= 5 && "Can't handle this yet");
764    for (unsigned i = 0, e = D.Struct_NumElements; i != e; ++i)
765      Elts[i] = DecodeFixedType(Infos, Tys, Context);
766    return StructType::get(Context, makeArrayRef(Elts,D.Struct_NumElements));
767  }
768
769  case IITDescriptor::Argument:
770    return Tys[D.getArgumentNumber()];
771  case IITDescriptor::ExtendArgument: {
772    Type *Ty = Tys[D.getArgumentNumber()];
773    if (VectorType *VTy = dyn_cast<VectorType>(Ty))
774      return VectorType::getExtendedElementVectorType(VTy);
775
776    return IntegerType::get(Context, 2 * cast<IntegerType>(Ty)->getBitWidth());
777  }
778  case IITDescriptor::TruncArgument: {
779    Type *Ty = Tys[D.getArgumentNumber()];
780    if (VectorType *VTy = dyn_cast<VectorType>(Ty))
781      return VectorType::getTruncatedElementVectorType(VTy);
782
783    IntegerType *ITy = cast<IntegerType>(Ty);
784    assert(ITy->getBitWidth() % 2 == 0);
785    return IntegerType::get(Context, ITy->getBitWidth() / 2);
786  }
787  case IITDescriptor::HalfVecArgument:
788    return VectorType::getHalfElementsVectorType(cast<VectorType>(
789                                                  Tys[D.getArgumentNumber()]));
790  case IITDescriptor::SameVecWidthArgument: {
791    Type *EltTy = DecodeFixedType(Infos, Tys, Context);
792    Type *Ty = Tys[D.getArgumentNumber()];
793    if (VectorType *VTy = dyn_cast<VectorType>(Ty)) {
794      return VectorType::get(EltTy, VTy->getNumElements());
795    }
796    llvm_unreachable("unhandled");
797  }
798  case IITDescriptor::PtrToArgument: {
799    Type *Ty = Tys[D.getArgumentNumber()];
800    return PointerType::getUnqual(Ty);
801  }
802  case IITDescriptor::VecOfPtrsToElt: {
803    Type *Ty = Tys[D.getArgumentNumber()];
804    VectorType *VTy = dyn_cast<VectorType>(Ty);
805    if (!VTy)
806      llvm_unreachable("Expected an argument of Vector Type");
807    Type *EltTy = VTy->getVectorElementType();
808    return VectorType::get(PointerType::getUnqual(EltTy),
809                           VTy->getNumElements());
810  }
811 }
812  llvm_unreachable("unhandled");
813}
814
815
816
817FunctionType *Intrinsic::getType(LLVMContext &Context,
818                                 ID id, ArrayRef<Type*> Tys) {
819  SmallVector<IITDescriptor, 8> Table;
820  getIntrinsicInfoTableEntries(id, Table);
821
822  ArrayRef<IITDescriptor> TableRef = Table;
823  Type *ResultTy = DecodeFixedType(TableRef, Tys, Context);
824
825  SmallVector<Type*, 8> ArgTys;
826  while (!TableRef.empty())
827    ArgTys.push_back(DecodeFixedType(TableRef, Tys, Context));
828
829  // DecodeFixedType returns Void for IITDescriptor::Void and IITDescriptor::VarArg
830  // If we see void type as the type of the last argument, it is vararg intrinsic
831  if (!ArgTys.empty() && ArgTys.back()->isVoidTy()) {
832    ArgTys.pop_back();
833    return FunctionType::get(ResultTy, ArgTys, true);
834  }
835  return FunctionType::get(ResultTy, ArgTys, false);
836}
837
838bool Intrinsic::isOverloaded(ID id) {
839#define GET_INTRINSIC_OVERLOAD_TABLE
840#include "llvm/IR/Intrinsics.gen"
841#undef GET_INTRINSIC_OVERLOAD_TABLE
842}
843
844/// This defines the "Intrinsic::getAttributes(ID id)" method.
845#define GET_INTRINSIC_ATTRIBUTES
846#include "llvm/IR/Intrinsics.gen"
847#undef GET_INTRINSIC_ATTRIBUTES
848
849Function *Intrinsic::getDeclaration(Module *M, ID id, ArrayRef<Type*> Tys) {
850  // There can never be multiple globals with the same name of different types,
851  // because intrinsics must be a specific type.
852  return
853    cast<Function>(M->getOrInsertFunction(getName(id, Tys),
854                                          getType(M->getContext(), id, Tys)));
855}
856
857// This defines the "Intrinsic::getIntrinsicForGCCBuiltin()" method.
858#define GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
859#include "llvm/IR/Intrinsics.gen"
860#undef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
861
862// This defines the "Intrinsic::getIntrinsicForMSBuiltin()" method.
863#define GET_LLVM_INTRINSIC_FOR_MS_BUILTIN
864#include "llvm/IR/Intrinsics.gen"
865#undef GET_LLVM_INTRINSIC_FOR_MS_BUILTIN
866
867/// hasAddressTaken - returns true if there are any uses of this function
868/// other than direct calls or invokes to it.
869bool Function::hasAddressTaken(const User* *PutOffender) const {
870  for (const Use &U : uses()) {
871    const User *FU = U.getUser();
872    if (isa<BlockAddress>(FU))
873      continue;
874    if (!isa<CallInst>(FU) && !isa<InvokeInst>(FU))
875      return PutOffender ? (*PutOffender = FU, true) : true;
876    ImmutableCallSite CS(cast<Instruction>(FU));
877    if (!CS.isCallee(&U))
878      return PutOffender ? (*PutOffender = FU, true) : true;
879  }
880  return false;
881}
882
883bool Function::isDefTriviallyDead() const {
884  // Check the linkage
885  if (!hasLinkOnceLinkage() && !hasLocalLinkage() &&
886      !hasAvailableExternallyLinkage())
887    return false;
888
889  // Check if the function is used by anything other than a blockaddress.
890  for (const User *U : users())
891    if (!isa<BlockAddress>(U))
892      return false;
893
894  return true;
895}
896
897/// callsFunctionThatReturnsTwice - Return true if the function has a call to
898/// setjmp or other function that gcc recognizes as "returning twice".
899bool Function::callsFunctionThatReturnsTwice() const {
900  for (const_inst_iterator
901         I = inst_begin(this), E = inst_end(this); I != E; ++I) {
902    ImmutableCallSite CS(&*I);
903    if (CS && CS.hasFnAttr(Attribute::ReturnsTwice))
904      return true;
905  }
906
907  return false;
908}
909
910Constant *Function::getPrefixData() const {
911  assert(hasPrefixData());
912  const LLVMContextImpl::PrefixDataMapTy &PDMap =
913      getContext().pImpl->PrefixDataMap;
914  assert(PDMap.find(this) != PDMap.end());
915  return cast<Constant>(PDMap.find(this)->second->getReturnValue());
916}
917
918void Function::setPrefixData(Constant *PrefixData) {
919  if (!PrefixData && !hasPrefixData())
920    return;
921
922  unsigned SCData = getSubclassDataFromValue();
923  LLVMContextImpl::PrefixDataMapTy &PDMap = getContext().pImpl->PrefixDataMap;
924  ReturnInst *&PDHolder = PDMap[this];
925  if (PrefixData) {
926    if (PDHolder)
927      PDHolder->setOperand(0, PrefixData);
928    else
929      PDHolder = ReturnInst::Create(getContext(), PrefixData);
930    SCData |= (1<<1);
931  } else {
932    delete PDHolder;
933    PDMap.erase(this);
934    SCData &= ~(1<<1);
935  }
936  setValueSubclassData(SCData);
937}
938
939Constant *Function::getPrologueData() const {
940  assert(hasPrologueData());
941  const LLVMContextImpl::PrologueDataMapTy &SOMap =
942      getContext().pImpl->PrologueDataMap;
943  assert(SOMap.find(this) != SOMap.end());
944  return cast<Constant>(SOMap.find(this)->second->getReturnValue());
945}
946
947void Function::setPrologueData(Constant *PrologueData) {
948  if (!PrologueData && !hasPrologueData())
949    return;
950
951  unsigned PDData = getSubclassDataFromValue();
952  LLVMContextImpl::PrologueDataMapTy &PDMap = getContext().pImpl->PrologueDataMap;
953  ReturnInst *&PDHolder = PDMap[this];
954  if (PrologueData) {
955    if (PDHolder)
956      PDHolder->setOperand(0, PrologueData);
957    else
958      PDHolder = ReturnInst::Create(getContext(), PrologueData);
959    PDData |= (1<<2);
960  } else {
961    delete PDHolder;
962    PDMap.erase(this);
963    PDData &= ~(1<<2);
964  }
965  setValueSubclassData(PDData);
966}
967