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/DerivedTypes.h"
22#include "llvm/IR/IntrinsicInst.h"
23#include "llvm/IR/LLVMContext.h"
24#include "llvm/IR/Module.h"
25#include "llvm/Support/CallSite.h"
26#include "llvm/Support/InstIterator.h"
27#include "llvm/Support/LeakDetector.h"
28#include "llvm/Support/ManagedStatic.h"
29#include "llvm/Support/RWMutex.h"
30#include "llvm/Support/StringPool.h"
31#include "llvm/Support/Threading.h"
32using namespace llvm;
33
34// Explicit instantiations of SymbolTableListTraits since some of the methods
35// are not in the public header file...
36template class llvm::SymbolTableListTraits<Argument, Function>;
37template class llvm::SymbolTableListTraits<BasicBlock, Function>;
38
39//===----------------------------------------------------------------------===//
40// Argument Implementation
41//===----------------------------------------------------------------------===//
42
43void Argument::anchor() { }
44
45Argument::Argument(Type *Ty, const Twine &Name, Function *Par)
46  : Value(Ty, Value::ArgumentVal) {
47  Parent = 0;
48
49  // Make sure that we get added to a function
50  LeakDetector::addGarbageObject(this);
51
52  if (Par)
53    Par->getArgumentList().push_back(this);
54  setName(Name);
55}
56
57void Argument::setParent(Function *parent) {
58  if (getParent())
59    LeakDetector::addGarbageObject(this);
60  Parent = parent;
61  if (getParent())
62    LeakDetector::removeGarbageObject(this);
63}
64
65/// getArgNo - Return the index of this formal argument in its containing
66/// function.  For example in "void foo(int a, float b)" a is 0 and b is 1.
67unsigned Argument::getArgNo() const {
68  const Function *F = getParent();
69  assert(F && "Argument is not in a function");
70
71  Function::const_arg_iterator AI = F->arg_begin();
72  unsigned ArgIdx = 0;
73  for (; &*AI != this; ++AI)
74    ++ArgIdx;
75
76  return ArgIdx;
77}
78
79/// hasByValAttr - Return true if this argument has the byval attribute on it
80/// in its containing function.
81bool Argument::hasByValAttr() const {
82  if (!getType()->isPointerTy()) return false;
83  return getParent()->getAttributes().
84    hasAttribute(getArgNo()+1, Attribute::ByVal);
85}
86
87unsigned Argument::getParamAlignment() const {
88  assert(getType()->isPointerTy() && "Only pointers have alignments");
89  return getParent()->getParamAlignment(getArgNo()+1);
90
91}
92
93/// hasNestAttr - Return true if this argument has the nest attribute on
94/// it in its containing function.
95bool Argument::hasNestAttr() const {
96  if (!getType()->isPointerTy()) return false;
97  return getParent()->getAttributes().
98    hasAttribute(getArgNo()+1, Attribute::Nest);
99}
100
101/// hasNoAliasAttr - Return true if this argument has the noalias attribute on
102/// it in its containing function.
103bool Argument::hasNoAliasAttr() const {
104  if (!getType()->isPointerTy()) return false;
105  return getParent()->getAttributes().
106    hasAttribute(getArgNo()+1, Attribute::NoAlias);
107}
108
109/// hasNoCaptureAttr - Return true if this argument has the nocapture attribute
110/// on it in its containing function.
111bool Argument::hasNoCaptureAttr() const {
112  if (!getType()->isPointerTy()) return false;
113  return getParent()->getAttributes().
114    hasAttribute(getArgNo()+1, Attribute::NoCapture);
115}
116
117/// hasSRetAttr - Return true if this argument has the sret attribute on
118/// it in its containing function.
119bool Argument::hasStructRetAttr() const {
120  if (!getType()->isPointerTy()) return false;
121  if (this != getParent()->arg_begin())
122    return false; // StructRet param must be first param
123  return getParent()->getAttributes().
124    hasAttribute(1, Attribute::StructRet);
125}
126
127/// addAttr - Add attributes to an argument.
128void Argument::addAttr(AttributeSet AS) {
129  assert(AS.getNumSlots() <= 1 &&
130         "Trying to add more than one attribute set to an argument!");
131  AttrBuilder B(AS, AS.getSlotIndex(0));
132  getParent()->addAttributes(getArgNo() + 1,
133                             AttributeSet::get(Parent->getContext(),
134                                               getArgNo() + 1, B));
135}
136
137/// removeAttr - Remove attributes from an argument.
138void Argument::removeAttr(AttributeSet AS) {
139  assert(AS.getNumSlots() <= 1 &&
140         "Trying to remove more than one attribute set from an argument!");
141  AttrBuilder B(AS, AS.getSlotIndex(0));
142  getParent()->removeAttributes(getArgNo() + 1,
143                                AttributeSet::get(Parent->getContext(),
144                                                  getArgNo() + 1, B));
145}
146
147//===----------------------------------------------------------------------===//
148// Helper Methods in Function
149//===----------------------------------------------------------------------===//
150
151LLVMContext &Function::getContext() const {
152  return getType()->getContext();
153}
154
155FunctionType *Function::getFunctionType() const {
156  return cast<FunctionType>(getType()->getElementType());
157}
158
159bool Function::isVarArg() const {
160  return getFunctionType()->isVarArg();
161}
162
163Type *Function::getReturnType() const {
164  return getFunctionType()->getReturnType();
165}
166
167void Function::removeFromParent() {
168  getParent()->getFunctionList().remove(this);
169}
170
171void Function::eraseFromParent() {
172  getParent()->getFunctionList().erase(this);
173}
174
175//===----------------------------------------------------------------------===//
176// Function Implementation
177//===----------------------------------------------------------------------===//
178
179Function::Function(FunctionType *Ty, LinkageTypes Linkage,
180                   const Twine &name, Module *ParentModule)
181  : GlobalValue(PointerType::getUnqual(Ty),
182                Value::FunctionVal, 0, 0, Linkage, name) {
183  assert(FunctionType::isValidReturnType(getReturnType()) &&
184         "invalid return type");
185  SymTab = new ValueSymbolTable();
186
187  // If the function has arguments, mark them as lazily built.
188  if (Ty->getNumParams())
189    setValueSubclassData(1);   // Set the "has lazy arguments" bit.
190
191  // Make sure that we get added to a function
192  LeakDetector::addGarbageObject(this);
193
194  if (ParentModule)
195    ParentModule->getFunctionList().push_back(this);
196
197  // Ensure intrinsics have the right parameter attributes.
198  if (unsigned IID = getIntrinsicID())
199    setAttributes(Intrinsic::getAttributes(getContext(), Intrinsic::ID(IID)));
200
201}
202
203Function::~Function() {
204  dropAllReferences();    // After this it is safe to delete instructions.
205
206  // Delete all of the method arguments and unlink from symbol table...
207  ArgumentList.clear();
208  delete SymTab;
209
210  // Remove the function from the on-the-side GC table.
211  clearGC();
212
213  // Remove the intrinsicID from the Cache.
214  if(getValueName() && isIntrinsic())
215    getContext().pImpl->IntrinsicIDCache.erase(this);
216}
217
218void Function::BuildLazyArguments() const {
219  // Create the arguments vector, all arguments start out unnamed.
220  FunctionType *FT = getFunctionType();
221  for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
222    assert(!FT->getParamType(i)->isVoidTy() &&
223           "Cannot have void typed arguments!");
224    ArgumentList.push_back(new Argument(FT->getParamType(i)));
225  }
226
227  // Clear the lazy arguments bit.
228  unsigned SDC = getSubclassDataFromValue();
229  const_cast<Function*>(this)->setValueSubclassData(SDC &= ~1);
230}
231
232size_t Function::arg_size() const {
233  return getFunctionType()->getNumParams();
234}
235bool Function::arg_empty() const {
236  return getFunctionType()->getNumParams() == 0;
237}
238
239void Function::setParent(Module *parent) {
240  if (getParent())
241    LeakDetector::addGarbageObject(this);
242  Parent = parent;
243  if (getParent())
244    LeakDetector::removeGarbageObject(this);
245}
246
247// dropAllReferences() - This function causes all the subinstructions to "let
248// go" of all references that they are maintaining.  This allows one to
249// 'delete' a whole class at a time, even though there may be circular
250// references... first all references are dropped, and all use counts go to
251// zero.  Then everything is deleted for real.  Note that no operations are
252// valid on an object that has "dropped all references", except operator
253// delete.
254//
255void Function::dropAllReferences() {
256  for (iterator I = begin(), E = end(); I != E; ++I)
257    I->dropAllReferences();
258
259  // Delete all basic blocks. They are now unused, except possibly by
260  // blockaddresses, but BasicBlock's destructor takes care of those.
261  while (!BasicBlocks.empty())
262    BasicBlocks.begin()->eraseFromParent();
263}
264
265void Function::addAttribute(unsigned i, Attribute::AttrKind attr) {
266  AttributeSet PAL = getAttributes();
267  PAL = PAL.addAttribute(getContext(), i, attr);
268  setAttributes(PAL);
269}
270
271void Function::addAttributes(unsigned i, AttributeSet attrs) {
272  AttributeSet PAL = getAttributes();
273  PAL = PAL.addAttributes(getContext(), i, attrs);
274  setAttributes(PAL);
275}
276
277void Function::removeAttributes(unsigned i, AttributeSet attrs) {
278  AttributeSet PAL = getAttributes();
279  PAL = PAL.removeAttributes(getContext(), i, attrs);
280  setAttributes(PAL);
281}
282
283// Maintain the GC name for each function in an on-the-side table. This saves
284// allocating an additional word in Function for programs which do not use GC
285// (i.e., most programs) at the cost of increased overhead for clients which do
286// use GC.
287static DenseMap<const Function*,PooledStringPtr> *GCNames;
288static StringPool *GCNamePool;
289static ManagedStatic<sys::SmartRWMutex<true> > GCLock;
290
291bool Function::hasGC() const {
292  sys::SmartScopedReader<true> Reader(*GCLock);
293  return GCNames && GCNames->count(this);
294}
295
296const char *Function::getGC() const {
297  assert(hasGC() && "Function has no collector");
298  sys::SmartScopedReader<true> Reader(*GCLock);
299  return *(*GCNames)[this];
300}
301
302void Function::setGC(const char *Str) {
303  sys::SmartScopedWriter<true> Writer(*GCLock);
304  if (!GCNamePool)
305    GCNamePool = new StringPool();
306  if (!GCNames)
307    GCNames = new DenseMap<const Function*,PooledStringPtr>();
308  (*GCNames)[this] = GCNamePool->intern(Str);
309}
310
311void Function::clearGC() {
312  sys::SmartScopedWriter<true> Writer(*GCLock);
313  if (GCNames) {
314    GCNames->erase(this);
315    if (GCNames->empty()) {
316      delete GCNames;
317      GCNames = 0;
318      if (GCNamePool->empty()) {
319        delete GCNamePool;
320        GCNamePool = 0;
321      }
322    }
323  }
324}
325
326/// copyAttributesFrom - copy all additional attributes (those not needed to
327/// create a Function) from the Function Src to this one.
328void Function::copyAttributesFrom(const GlobalValue *Src) {
329  assert(isa<Function>(Src) && "Expected a Function!");
330  GlobalValue::copyAttributesFrom(Src);
331  const Function *SrcF = cast<Function>(Src);
332  setCallingConv(SrcF->getCallingConv());
333  setAttributes(SrcF->getAttributes());
334  if (SrcF->hasGC())
335    setGC(SrcF->getGC());
336  else
337    clearGC();
338}
339
340/// getIntrinsicID - This method returns the ID number of the specified
341/// function, or Intrinsic::not_intrinsic if the function is not an
342/// intrinsic, or if the pointer is null.  This value is always defined to be
343/// zero to allow easy checking for whether a function is intrinsic or not.  The
344/// particular intrinsic functions which correspond to this value are defined in
345/// llvm/Intrinsics.h.  Results are cached in the LLVM context, subsequent
346/// requests for the same ID return results much faster from the cache.
347///
348unsigned Function::getIntrinsicID() const {
349  const ValueName *ValName = this->getValueName();
350  if (!ValName || !isIntrinsic())
351    return 0;
352
353  LLVMContextImpl::IntrinsicIDCacheTy &IntrinsicIDCache =
354    getContext().pImpl->IntrinsicIDCache;
355  if(!IntrinsicIDCache.count(this)) {
356    unsigned Id = lookupIntrinsicID();
357    IntrinsicIDCache[this]=Id;
358    return Id;
359  }
360  return IntrinsicIDCache[this];
361}
362
363/// This private method does the actual lookup of an intrinsic ID when the query
364/// could not be answered from the cache.
365unsigned Function::lookupIntrinsicID() const {
366  const ValueName *ValName = this->getValueName();
367  unsigned Len = ValName->getKeyLength();
368  const char *Name = ValName->getKeyData();
369
370#define GET_FUNCTION_RECOGNIZER
371#include "llvm/IR/Intrinsics.gen"
372#undef GET_FUNCTION_RECOGNIZER
373
374  return 0;
375}
376
377std::string Intrinsic::getName(ID id, ArrayRef<Type*> Tys) {
378  assert(id < num_intrinsics && "Invalid intrinsic ID!");
379  static const char * const Table[] = {
380    "not_intrinsic",
381#define GET_INTRINSIC_NAME_TABLE
382#include "llvm/IR/Intrinsics.gen"
383#undef GET_INTRINSIC_NAME_TABLE
384  };
385  if (Tys.empty())
386    return Table[id];
387  std::string Result(Table[id]);
388  for (unsigned i = 0; i < Tys.size(); ++i) {
389    if (PointerType* PTyp = dyn_cast<PointerType>(Tys[i])) {
390      Result += ".p" + llvm::utostr(PTyp->getAddressSpace()) +
391                EVT::getEVT(PTyp->getElementType()).getEVTString();
392    }
393    else if (Tys[i])
394      Result += "." + EVT::getEVT(Tys[i]).getEVTString();
395  }
396  return Result;
397}
398
399
400/// IIT_Info - These are enumerators that describe the entries returned by the
401/// getIntrinsicInfoTableEntries function.
402///
403/// NOTE: This must be kept in synch with the copy in TblGen/IntrinsicEmitter!
404enum IIT_Info {
405  // Common values should be encoded with 0-15.
406  IIT_Done = 0,
407  IIT_I1   = 1,
408  IIT_I8   = 2,
409  IIT_I16  = 3,
410  IIT_I32  = 4,
411  IIT_I64  = 5,
412  IIT_F16  = 6,
413  IIT_F32  = 7,
414  IIT_F64  = 8,
415  IIT_V2   = 9,
416  IIT_V4   = 10,
417  IIT_V8   = 11,
418  IIT_V16  = 12,
419  IIT_V32  = 13,
420  IIT_PTR  = 14,
421  IIT_ARG  = 15,
422
423  // Values from 16+ are only encodable with the inefficient encoding.
424  IIT_MMX  = 16,
425  IIT_METADATA = 17,
426  IIT_EMPTYSTRUCT = 18,
427  IIT_STRUCT2 = 19,
428  IIT_STRUCT3 = 20,
429  IIT_STRUCT4 = 21,
430  IIT_STRUCT5 = 22,
431  IIT_EXTEND_VEC_ARG = 23,
432  IIT_TRUNC_VEC_ARG = 24,
433  IIT_ANYPTR = 25
434};
435
436
437static void DecodeIITType(unsigned &NextElt, ArrayRef<unsigned char> Infos,
438                      SmallVectorImpl<Intrinsic::IITDescriptor> &OutputTable) {
439  IIT_Info Info = IIT_Info(Infos[NextElt++]);
440  unsigned StructElts = 2;
441  using namespace Intrinsic;
442
443  switch (Info) {
444  case IIT_Done:
445    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Void, 0));
446    return;
447  case IIT_MMX:
448    OutputTable.push_back(IITDescriptor::get(IITDescriptor::MMX, 0));
449    return;
450  case IIT_METADATA:
451    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Metadata, 0));
452    return;
453  case IIT_F16:
454    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Half, 0));
455    return;
456  case IIT_F32:
457    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Float, 0));
458    return;
459  case IIT_F64:
460    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Double, 0));
461    return;
462  case IIT_I1:
463    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 1));
464    return;
465  case IIT_I8:
466    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 8));
467    return;
468  case IIT_I16:
469    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer,16));
470    return;
471  case IIT_I32:
472    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 32));
473    return;
474  case IIT_I64:
475    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 64));
476    return;
477  case IIT_V2:
478    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 2));
479    DecodeIITType(NextElt, Infos, OutputTable);
480    return;
481  case IIT_V4:
482    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 4));
483    DecodeIITType(NextElt, Infos, OutputTable);
484    return;
485  case IIT_V8:
486    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 8));
487    DecodeIITType(NextElt, Infos, OutputTable);
488    return;
489  case IIT_V16:
490    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 16));
491    DecodeIITType(NextElt, Infos, OutputTable);
492    return;
493  case IIT_V32:
494    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 32));
495    DecodeIITType(NextElt, Infos, OutputTable);
496    return;
497  case IIT_PTR:
498    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer, 0));
499    DecodeIITType(NextElt, Infos, OutputTable);
500    return;
501  case IIT_ANYPTR: {  // [ANYPTR addrspace, subtype]
502    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer,
503                                             Infos[NextElt++]));
504    DecodeIITType(NextElt, Infos, OutputTable);
505    return;
506  }
507  case IIT_ARG: {
508    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
509    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Argument, ArgInfo));
510    return;
511  }
512  case IIT_EXTEND_VEC_ARG: {
513    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
514    OutputTable.push_back(IITDescriptor::get(IITDescriptor::ExtendVecArgument,
515                                             ArgInfo));
516    return;
517  }
518  case IIT_TRUNC_VEC_ARG: {
519    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
520    OutputTable.push_back(IITDescriptor::get(IITDescriptor::TruncVecArgument,
521                                             ArgInfo));
522    return;
523  }
524  case IIT_EMPTYSTRUCT:
525    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct, 0));
526    return;
527  case IIT_STRUCT5: ++StructElts; // FALL THROUGH.
528  case IIT_STRUCT4: ++StructElts; // FALL THROUGH.
529  case IIT_STRUCT3: ++StructElts; // FALL THROUGH.
530  case IIT_STRUCT2: {
531    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct,StructElts));
532
533    for (unsigned i = 0; i != StructElts; ++i)
534      DecodeIITType(NextElt, Infos, OutputTable);
535    return;
536  }
537  }
538  llvm_unreachable("unhandled");
539}
540
541
542#define GET_INTRINSIC_GENERATOR_GLOBAL
543#include "llvm/IR/Intrinsics.gen"
544#undef GET_INTRINSIC_GENERATOR_GLOBAL
545
546void Intrinsic::getIntrinsicInfoTableEntries(ID id,
547                                             SmallVectorImpl<IITDescriptor> &T){
548  // Check to see if the intrinsic's type was expressible by the table.
549  unsigned TableVal = IIT_Table[id-1];
550
551  // Decode the TableVal into an array of IITValues.
552  SmallVector<unsigned char, 8> IITValues;
553  ArrayRef<unsigned char> IITEntries;
554  unsigned NextElt = 0;
555  if ((TableVal >> 31) != 0) {
556    // This is an offset into the IIT_LongEncodingTable.
557    IITEntries = IIT_LongEncodingTable;
558
559    // Strip sentinel bit.
560    NextElt = (TableVal << 1) >> 1;
561  } else {
562    // Decode the TableVal into an array of IITValues.  If the entry was encoded
563    // into a single word in the table itself, decode it now.
564    do {
565      IITValues.push_back(TableVal & 0xF);
566      TableVal >>= 4;
567    } while (TableVal);
568
569    IITEntries = IITValues;
570    NextElt = 0;
571  }
572
573  // Okay, decode the table into the output vector of IITDescriptors.
574  DecodeIITType(NextElt, IITEntries, T);
575  while (NextElt != IITEntries.size() && IITEntries[NextElt] != 0)
576    DecodeIITType(NextElt, IITEntries, T);
577}
578
579
580static Type *DecodeFixedType(ArrayRef<Intrinsic::IITDescriptor> &Infos,
581                             ArrayRef<Type*> Tys, LLVMContext &Context) {
582  using namespace Intrinsic;
583  IITDescriptor D = Infos.front();
584  Infos = Infos.slice(1);
585
586  switch (D.Kind) {
587  case IITDescriptor::Void: return Type::getVoidTy(Context);
588  case IITDescriptor::MMX: return Type::getX86_MMXTy(Context);
589  case IITDescriptor::Metadata: return Type::getMetadataTy(Context);
590  case IITDescriptor::Half: return Type::getHalfTy(Context);
591  case IITDescriptor::Float: return Type::getFloatTy(Context);
592  case IITDescriptor::Double: return Type::getDoubleTy(Context);
593
594  case IITDescriptor::Integer:
595    return IntegerType::get(Context, D.Integer_Width);
596  case IITDescriptor::Vector:
597    return VectorType::get(DecodeFixedType(Infos, Tys, Context),D.Vector_Width);
598  case IITDescriptor::Pointer:
599    return PointerType::get(DecodeFixedType(Infos, Tys, Context),
600                            D.Pointer_AddressSpace);
601  case IITDescriptor::Struct: {
602    Type *Elts[5];
603    assert(D.Struct_NumElements <= 5 && "Can't handle this yet");
604    for (unsigned i = 0, e = D.Struct_NumElements; i != e; ++i)
605      Elts[i] = DecodeFixedType(Infos, Tys, Context);
606    return StructType::get(Context, ArrayRef<Type*>(Elts,D.Struct_NumElements));
607  }
608
609  case IITDescriptor::Argument:
610    return Tys[D.getArgumentNumber()];
611  case IITDescriptor::ExtendVecArgument:
612    return VectorType::getExtendedElementVectorType(cast<VectorType>(
613                                                  Tys[D.getArgumentNumber()]));
614
615  case IITDescriptor::TruncVecArgument:
616    return VectorType::getTruncatedElementVectorType(cast<VectorType>(
617                                                  Tys[D.getArgumentNumber()]));
618  }
619  llvm_unreachable("unhandled");
620}
621
622
623
624FunctionType *Intrinsic::getType(LLVMContext &Context,
625                                 ID id, ArrayRef<Type*> Tys) {
626  SmallVector<IITDescriptor, 8> Table;
627  getIntrinsicInfoTableEntries(id, Table);
628
629  ArrayRef<IITDescriptor> TableRef = Table;
630  Type *ResultTy = DecodeFixedType(TableRef, Tys, Context);
631
632  SmallVector<Type*, 8> ArgTys;
633  while (!TableRef.empty())
634    ArgTys.push_back(DecodeFixedType(TableRef, Tys, Context));
635
636  return FunctionType::get(ResultTy, ArgTys, false);
637}
638
639bool Intrinsic::isOverloaded(ID id) {
640#define GET_INTRINSIC_OVERLOAD_TABLE
641#include "llvm/IR/Intrinsics.gen"
642#undef GET_INTRINSIC_OVERLOAD_TABLE
643}
644
645/// This defines the "Intrinsic::getAttributes(ID id)" method.
646#define GET_INTRINSIC_ATTRIBUTES
647#include "llvm/IR/Intrinsics.gen"
648#undef GET_INTRINSIC_ATTRIBUTES
649
650Function *Intrinsic::getDeclaration(Module *M, ID id, ArrayRef<Type*> Tys) {
651  // There can never be multiple globals with the same name of different types,
652  // because intrinsics must be a specific type.
653  return
654    cast<Function>(M->getOrInsertFunction(getName(id, Tys),
655                                          getType(M->getContext(), id, Tys)));
656}
657
658// This defines the "Intrinsic::getIntrinsicForGCCBuiltin()" method.
659#define GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
660#include "llvm/IR/Intrinsics.gen"
661#undef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
662
663/// hasAddressTaken - returns true if there are any uses of this function
664/// other than direct calls or invokes to it.
665bool Function::hasAddressTaken(const User* *PutOffender) const {
666  for (Value::const_use_iterator I = use_begin(), E = use_end(); I != E; ++I) {
667    const User *U = *I;
668    if (isa<BlockAddress>(U))
669      continue;
670    if (!isa<CallInst>(U) && !isa<InvokeInst>(U))
671      return PutOffender ? (*PutOffender = U, true) : true;
672    ImmutableCallSite CS(cast<Instruction>(U));
673    if (!CS.isCallee(I))
674      return PutOffender ? (*PutOffender = U, true) : true;
675  }
676  return false;
677}
678
679bool Function::isDefTriviallyDead() const {
680  // Check the linkage
681  if (!hasLinkOnceLinkage() && !hasLocalLinkage() &&
682      !hasAvailableExternallyLinkage())
683    return false;
684
685  // Check if the function is used by anything other than a blockaddress.
686  for (Value::const_use_iterator I = use_begin(), E = use_end(); I != E; ++I)
687    if (!isa<BlockAddress>(*I))
688      return false;
689
690  return true;
691}
692
693/// callsFunctionThatReturnsTwice - Return true if the function has a call to
694/// setjmp or other function that gcc recognizes as "returning twice".
695bool Function::callsFunctionThatReturnsTwice() const {
696  for (const_inst_iterator
697         I = inst_begin(this), E = inst_end(this); I != E; ++I) {
698    const CallInst* callInst = dyn_cast<CallInst>(&*I);
699    if (!callInst)
700      continue;
701    if (callInst->canReturnTwice())
702      return true;
703  }
704
705  return false;
706}
707
708