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/// hasReturnedAttr - Return true if this argument has the returned attribute on
128/// it in its containing function.
129bool Argument::hasReturnedAttr() const {
130  return getParent()->getAttributes().
131    hasAttribute(getArgNo()+1, Attribute::Returned);
132}
133
134/// Return true if this argument has the readonly or readnone attribute on it
135/// in its containing function.
136bool Argument::onlyReadsMemory() const {
137  return getParent()->getAttributes().
138      hasAttribute(getArgNo()+1, Attribute::ReadOnly) ||
139      getParent()->getAttributes().
140      hasAttribute(getArgNo()+1, Attribute::ReadNone);
141}
142
143/// addAttr - Add attributes to an argument.
144void Argument::addAttr(AttributeSet AS) {
145  assert(AS.getNumSlots() <= 1 &&
146         "Trying to add more than one attribute set to an argument!");
147  AttrBuilder B(AS, AS.getSlotIndex(0));
148  getParent()->addAttributes(getArgNo() + 1,
149                             AttributeSet::get(Parent->getContext(),
150                                               getArgNo() + 1, B));
151}
152
153/// removeAttr - Remove attributes from an argument.
154void Argument::removeAttr(AttributeSet AS) {
155  assert(AS.getNumSlots() <= 1 &&
156         "Trying to remove more than one attribute set from an argument!");
157  AttrBuilder B(AS, AS.getSlotIndex(0));
158  getParent()->removeAttributes(getArgNo() + 1,
159                                AttributeSet::get(Parent->getContext(),
160                                                  getArgNo() + 1, B));
161}
162
163//===----------------------------------------------------------------------===//
164// Helper Methods in Function
165//===----------------------------------------------------------------------===//
166
167LLVMContext &Function::getContext() const {
168  return getType()->getContext();
169}
170
171FunctionType *Function::getFunctionType() const {
172  return cast<FunctionType>(getType()->getElementType());
173}
174
175bool Function::isVarArg() const {
176  return getFunctionType()->isVarArg();
177}
178
179Type *Function::getReturnType() const {
180  return getFunctionType()->getReturnType();
181}
182
183void Function::removeFromParent() {
184  getParent()->getFunctionList().remove(this);
185}
186
187void Function::eraseFromParent() {
188  getParent()->getFunctionList().erase(this);
189}
190
191//===----------------------------------------------------------------------===//
192// Function Implementation
193//===----------------------------------------------------------------------===//
194
195Function::Function(FunctionType *Ty, LinkageTypes Linkage,
196                   const Twine &name, Module *ParentModule)
197  : GlobalValue(PointerType::getUnqual(Ty),
198                Value::FunctionVal, 0, 0, Linkage, name) {
199  assert(FunctionType::isValidReturnType(getReturnType()) &&
200         "invalid return type");
201  SymTab = new ValueSymbolTable();
202
203  // If the function has arguments, mark them as lazily built.
204  if (Ty->getNumParams())
205    setValueSubclassData(1);   // Set the "has lazy arguments" bit.
206
207  // Make sure that we get added to a function
208  LeakDetector::addGarbageObject(this);
209
210  if (ParentModule)
211    ParentModule->getFunctionList().push_back(this);
212
213  // Ensure intrinsics have the right parameter attributes.
214  if (unsigned IID = getIntrinsicID())
215    setAttributes(Intrinsic::getAttributes(getContext(), Intrinsic::ID(IID)));
216
217}
218
219Function::~Function() {
220  dropAllReferences();    // After this it is safe to delete instructions.
221
222  // Delete all of the method arguments and unlink from symbol table...
223  ArgumentList.clear();
224  delete SymTab;
225
226  // Remove the function from the on-the-side GC table.
227  clearGC();
228
229  // Remove the intrinsicID from the Cache.
230  if (getValueName() && isIntrinsic())
231    getContext().pImpl->IntrinsicIDCache.erase(this);
232}
233
234void Function::BuildLazyArguments() const {
235  // Create the arguments vector, all arguments start out unnamed.
236  FunctionType *FT = getFunctionType();
237  for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
238    assert(!FT->getParamType(i)->isVoidTy() &&
239           "Cannot have void typed arguments!");
240    ArgumentList.push_back(new Argument(FT->getParamType(i)));
241  }
242
243  // Clear the lazy arguments bit.
244  unsigned SDC = getSubclassDataFromValue();
245  const_cast<Function*>(this)->setValueSubclassData(SDC &= ~1);
246}
247
248size_t Function::arg_size() const {
249  return getFunctionType()->getNumParams();
250}
251bool Function::arg_empty() const {
252  return getFunctionType()->getNumParams() == 0;
253}
254
255void Function::setParent(Module *parent) {
256  if (getParent())
257    LeakDetector::addGarbageObject(this);
258  Parent = parent;
259  if (getParent())
260    LeakDetector::removeGarbageObject(this);
261}
262
263// dropAllReferences() - This function causes all the subinstructions to "let
264// go" of all references that they are maintaining.  This allows one to
265// 'delete' a whole class at a time, even though there may be circular
266// references... first all references are dropped, and all use counts go to
267// zero.  Then everything is deleted for real.  Note that no operations are
268// valid on an object that has "dropped all references", except operator
269// delete.
270//
271void Function::dropAllReferences() {
272  for (iterator I = begin(), E = end(); I != E; ++I)
273    I->dropAllReferences();
274
275  // Delete all basic blocks. They are now unused, except possibly by
276  // blockaddresses, but BasicBlock's destructor takes care of those.
277  while (!BasicBlocks.empty())
278    BasicBlocks.begin()->eraseFromParent();
279}
280
281void Function::addAttribute(unsigned i, Attribute::AttrKind attr) {
282  AttributeSet PAL = getAttributes();
283  PAL = PAL.addAttribute(getContext(), i, attr);
284  setAttributes(PAL);
285}
286
287void Function::addAttributes(unsigned i, AttributeSet attrs) {
288  AttributeSet PAL = getAttributes();
289  PAL = PAL.addAttributes(getContext(), i, attrs);
290  setAttributes(PAL);
291}
292
293void Function::removeAttributes(unsigned i, AttributeSet attrs) {
294  AttributeSet PAL = getAttributes();
295  PAL = PAL.removeAttributes(getContext(), i, attrs);
296  setAttributes(PAL);
297}
298
299// Maintain the GC name for each function in an on-the-side table. This saves
300// allocating an additional word in Function for programs which do not use GC
301// (i.e., most programs) at the cost of increased overhead for clients which do
302// use GC.
303static DenseMap<const Function*,PooledStringPtr> *GCNames;
304static StringPool *GCNamePool;
305static ManagedStatic<sys::SmartRWMutex<true> > GCLock;
306
307bool Function::hasGC() const {
308  sys::SmartScopedReader<true> Reader(*GCLock);
309  return GCNames && GCNames->count(this);
310}
311
312const char *Function::getGC() const {
313  assert(hasGC() && "Function has no collector");
314  sys::SmartScopedReader<true> Reader(*GCLock);
315  return *(*GCNames)[this];
316}
317
318void Function::setGC(const char *Str) {
319  sys::SmartScopedWriter<true> Writer(*GCLock);
320  if (!GCNamePool)
321    GCNamePool = new StringPool();
322  if (!GCNames)
323    GCNames = new DenseMap<const Function*,PooledStringPtr>();
324  (*GCNames)[this] = GCNamePool->intern(Str);
325}
326
327void Function::clearGC() {
328  sys::SmartScopedWriter<true> Writer(*GCLock);
329  if (GCNames) {
330    GCNames->erase(this);
331    if (GCNames->empty()) {
332      delete GCNames;
333      GCNames = 0;
334      if (GCNamePool->empty()) {
335        delete GCNamePool;
336        GCNamePool = 0;
337      }
338    }
339  }
340}
341
342/// copyAttributesFrom - copy all additional attributes (those not needed to
343/// create a Function) from the Function Src to this one.
344void Function::copyAttributesFrom(const GlobalValue *Src) {
345  assert(isa<Function>(Src) && "Expected a Function!");
346  GlobalValue::copyAttributesFrom(Src);
347  const Function *SrcF = cast<Function>(Src);
348  setCallingConv(SrcF->getCallingConv());
349  setAttributes(SrcF->getAttributes());
350  if (SrcF->hasGC())
351    setGC(SrcF->getGC());
352  else
353    clearGC();
354}
355
356/// getIntrinsicID - This method returns the ID number of the specified
357/// function, or Intrinsic::not_intrinsic if the function is not an
358/// intrinsic, or if the pointer is null.  This value is always defined to be
359/// zero to allow easy checking for whether a function is intrinsic or not.  The
360/// particular intrinsic functions which correspond to this value are defined in
361/// llvm/Intrinsics.h.  Results are cached in the LLVM context, subsequent
362/// requests for the same ID return results much faster from the cache.
363///
364unsigned Function::getIntrinsicID() const {
365  const ValueName *ValName = this->getValueName();
366  if (!ValName || !isIntrinsic())
367    return 0;
368
369  LLVMContextImpl::IntrinsicIDCacheTy &IntrinsicIDCache =
370    getContext().pImpl->IntrinsicIDCache;
371  if (!IntrinsicIDCache.count(this)) {
372    unsigned Id = lookupIntrinsicID();
373    IntrinsicIDCache[this]=Id;
374    return Id;
375  }
376  return IntrinsicIDCache[this];
377}
378
379/// This private method does the actual lookup of an intrinsic ID when the query
380/// could not be answered from the cache.
381unsigned Function::lookupIntrinsicID() const {
382  const ValueName *ValName = this->getValueName();
383  unsigned Len = ValName->getKeyLength();
384  const char *Name = ValName->getKeyData();
385
386#define GET_FUNCTION_RECOGNIZER
387#include "llvm/IR/Intrinsics.gen"
388#undef GET_FUNCTION_RECOGNIZER
389
390  return 0;
391}
392
393std::string Intrinsic::getName(ID id, ArrayRef<Type*> Tys) {
394  assert(id < num_intrinsics && "Invalid intrinsic ID!");
395  static const char * const Table[] = {
396    "not_intrinsic",
397#define GET_INTRINSIC_NAME_TABLE
398#include "llvm/IR/Intrinsics.gen"
399#undef GET_INTRINSIC_NAME_TABLE
400  };
401  if (Tys.empty())
402    return Table[id];
403  std::string Result(Table[id]);
404  for (unsigned i = 0; i < Tys.size(); ++i) {
405    if (PointerType* PTyp = dyn_cast<PointerType>(Tys[i])) {
406      Result += ".p" + llvm::utostr(PTyp->getAddressSpace()) +
407                EVT::getEVT(PTyp->getElementType()).getEVTString();
408    }
409    else if (Tys[i])
410      Result += "." + EVT::getEVT(Tys[i]).getEVTString();
411  }
412  return Result;
413}
414
415
416/// IIT_Info - These are enumerators that describe the entries returned by the
417/// getIntrinsicInfoTableEntries function.
418///
419/// NOTE: This must be kept in synch with the copy in TblGen/IntrinsicEmitter!
420enum IIT_Info {
421  // Common values should be encoded with 0-15.
422  IIT_Done = 0,
423  IIT_I1   = 1,
424  IIT_I8   = 2,
425  IIT_I16  = 3,
426  IIT_I32  = 4,
427  IIT_I64  = 5,
428  IIT_F16  = 6,
429  IIT_F32  = 7,
430  IIT_F64  = 8,
431  IIT_V2   = 9,
432  IIT_V4   = 10,
433  IIT_V8   = 11,
434  IIT_V16  = 12,
435  IIT_V32  = 13,
436  IIT_PTR  = 14,
437  IIT_ARG  = 15,
438
439  // Values from 16+ are only encodable with the inefficient encoding.
440  IIT_MMX  = 16,
441  IIT_METADATA = 17,
442  IIT_EMPTYSTRUCT = 18,
443  IIT_STRUCT2 = 19,
444  IIT_STRUCT3 = 20,
445  IIT_STRUCT4 = 21,
446  IIT_STRUCT5 = 22,
447  IIT_EXTEND_VEC_ARG = 23,
448  IIT_TRUNC_VEC_ARG = 24,
449  IIT_ANYPTR = 25
450};
451
452
453static void DecodeIITType(unsigned &NextElt, ArrayRef<unsigned char> Infos,
454                      SmallVectorImpl<Intrinsic::IITDescriptor> &OutputTable) {
455  IIT_Info Info = IIT_Info(Infos[NextElt++]);
456  unsigned StructElts = 2;
457  using namespace Intrinsic;
458
459  switch (Info) {
460  case IIT_Done:
461    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Void, 0));
462    return;
463  case IIT_MMX:
464    OutputTable.push_back(IITDescriptor::get(IITDescriptor::MMX, 0));
465    return;
466  case IIT_METADATA:
467    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Metadata, 0));
468    return;
469  case IIT_F16:
470    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Half, 0));
471    return;
472  case IIT_F32:
473    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Float, 0));
474    return;
475  case IIT_F64:
476    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Double, 0));
477    return;
478  case IIT_I1:
479    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 1));
480    return;
481  case IIT_I8:
482    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 8));
483    return;
484  case IIT_I16:
485    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer,16));
486    return;
487  case IIT_I32:
488    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 32));
489    return;
490  case IIT_I64:
491    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 64));
492    return;
493  case IIT_V2:
494    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 2));
495    DecodeIITType(NextElt, Infos, OutputTable);
496    return;
497  case IIT_V4:
498    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 4));
499    DecodeIITType(NextElt, Infos, OutputTable);
500    return;
501  case IIT_V8:
502    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 8));
503    DecodeIITType(NextElt, Infos, OutputTable);
504    return;
505  case IIT_V16:
506    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 16));
507    DecodeIITType(NextElt, Infos, OutputTable);
508    return;
509  case IIT_V32:
510    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 32));
511    DecodeIITType(NextElt, Infos, OutputTable);
512    return;
513  case IIT_PTR:
514    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer, 0));
515    DecodeIITType(NextElt, Infos, OutputTable);
516    return;
517  case IIT_ANYPTR: {  // [ANYPTR addrspace, subtype]
518    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer,
519                                             Infos[NextElt++]));
520    DecodeIITType(NextElt, Infos, OutputTable);
521    return;
522  }
523  case IIT_ARG: {
524    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
525    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Argument, ArgInfo));
526    return;
527  }
528  case IIT_EXTEND_VEC_ARG: {
529    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
530    OutputTable.push_back(IITDescriptor::get(IITDescriptor::ExtendVecArgument,
531                                             ArgInfo));
532    return;
533  }
534  case IIT_TRUNC_VEC_ARG: {
535    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
536    OutputTable.push_back(IITDescriptor::get(IITDescriptor::TruncVecArgument,
537                                             ArgInfo));
538    return;
539  }
540  case IIT_EMPTYSTRUCT:
541    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct, 0));
542    return;
543  case IIT_STRUCT5: ++StructElts; // FALL THROUGH.
544  case IIT_STRUCT4: ++StructElts; // FALL THROUGH.
545  case IIT_STRUCT3: ++StructElts; // FALL THROUGH.
546  case IIT_STRUCT2: {
547    OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct,StructElts));
548
549    for (unsigned i = 0; i != StructElts; ++i)
550      DecodeIITType(NextElt, Infos, OutputTable);
551    return;
552  }
553  }
554  llvm_unreachable("unhandled");
555}
556
557
558#define GET_INTRINSIC_GENERATOR_GLOBAL
559#include "llvm/IR/Intrinsics.gen"
560#undef GET_INTRINSIC_GENERATOR_GLOBAL
561
562void Intrinsic::getIntrinsicInfoTableEntries(ID id,
563                                             SmallVectorImpl<IITDescriptor> &T){
564  // Check to see if the intrinsic's type was expressible by the table.
565  unsigned TableVal = IIT_Table[id-1];
566
567  // Decode the TableVal into an array of IITValues.
568  SmallVector<unsigned char, 8> IITValues;
569  ArrayRef<unsigned char> IITEntries;
570  unsigned NextElt = 0;
571  if ((TableVal >> 31) != 0) {
572    // This is an offset into the IIT_LongEncodingTable.
573    IITEntries = IIT_LongEncodingTable;
574
575    // Strip sentinel bit.
576    NextElt = (TableVal << 1) >> 1;
577  } else {
578    // Decode the TableVal into an array of IITValues.  If the entry was encoded
579    // into a single word in the table itself, decode it now.
580    do {
581      IITValues.push_back(TableVal & 0xF);
582      TableVal >>= 4;
583    } while (TableVal);
584
585    IITEntries = IITValues;
586    NextElt = 0;
587  }
588
589  // Okay, decode the table into the output vector of IITDescriptors.
590  DecodeIITType(NextElt, IITEntries, T);
591  while (NextElt != IITEntries.size() && IITEntries[NextElt] != 0)
592    DecodeIITType(NextElt, IITEntries, T);
593}
594
595
596static Type *DecodeFixedType(ArrayRef<Intrinsic::IITDescriptor> &Infos,
597                             ArrayRef<Type*> Tys, LLVMContext &Context) {
598  using namespace Intrinsic;
599  IITDescriptor D = Infos.front();
600  Infos = Infos.slice(1);
601
602  switch (D.Kind) {
603  case IITDescriptor::Void: return Type::getVoidTy(Context);
604  case IITDescriptor::MMX: return Type::getX86_MMXTy(Context);
605  case IITDescriptor::Metadata: return Type::getMetadataTy(Context);
606  case IITDescriptor::Half: return Type::getHalfTy(Context);
607  case IITDescriptor::Float: return Type::getFloatTy(Context);
608  case IITDescriptor::Double: return Type::getDoubleTy(Context);
609
610  case IITDescriptor::Integer:
611    return IntegerType::get(Context, D.Integer_Width);
612  case IITDescriptor::Vector:
613    return VectorType::get(DecodeFixedType(Infos, Tys, Context),D.Vector_Width);
614  case IITDescriptor::Pointer:
615    return PointerType::get(DecodeFixedType(Infos, Tys, Context),
616                            D.Pointer_AddressSpace);
617  case IITDescriptor::Struct: {
618    Type *Elts[5];
619    assert(D.Struct_NumElements <= 5 && "Can't handle this yet");
620    for (unsigned i = 0, e = D.Struct_NumElements; i != e; ++i)
621      Elts[i] = DecodeFixedType(Infos, Tys, Context);
622    return StructType::get(Context, ArrayRef<Type*>(Elts,D.Struct_NumElements));
623  }
624
625  case IITDescriptor::Argument:
626    return Tys[D.getArgumentNumber()];
627  case IITDescriptor::ExtendVecArgument:
628    return VectorType::getExtendedElementVectorType(cast<VectorType>(
629                                                  Tys[D.getArgumentNumber()]));
630
631  case IITDescriptor::TruncVecArgument:
632    return VectorType::getTruncatedElementVectorType(cast<VectorType>(
633                                                  Tys[D.getArgumentNumber()]));
634  }
635  llvm_unreachable("unhandled");
636}
637
638
639
640FunctionType *Intrinsic::getType(LLVMContext &Context,
641                                 ID id, ArrayRef<Type*> Tys) {
642  SmallVector<IITDescriptor, 8> Table;
643  getIntrinsicInfoTableEntries(id, Table);
644
645  ArrayRef<IITDescriptor> TableRef = Table;
646  Type *ResultTy = DecodeFixedType(TableRef, Tys, Context);
647
648  SmallVector<Type*, 8> ArgTys;
649  while (!TableRef.empty())
650    ArgTys.push_back(DecodeFixedType(TableRef, Tys, Context));
651
652  return FunctionType::get(ResultTy, ArgTys, false);
653}
654
655bool Intrinsic::isOverloaded(ID id) {
656#define GET_INTRINSIC_OVERLOAD_TABLE
657#include "llvm/IR/Intrinsics.gen"
658#undef GET_INTRINSIC_OVERLOAD_TABLE
659}
660
661/// This defines the "Intrinsic::getAttributes(ID id)" method.
662#define GET_INTRINSIC_ATTRIBUTES
663#include "llvm/IR/Intrinsics.gen"
664#undef GET_INTRINSIC_ATTRIBUTES
665
666Function *Intrinsic::getDeclaration(Module *M, ID id, ArrayRef<Type*> Tys) {
667  // There can never be multiple globals with the same name of different types,
668  // because intrinsics must be a specific type.
669  return
670    cast<Function>(M->getOrInsertFunction(getName(id, Tys),
671                                          getType(M->getContext(), id, Tys)));
672}
673
674// This defines the "Intrinsic::getIntrinsicForGCCBuiltin()" method.
675#define GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
676#include "llvm/IR/Intrinsics.gen"
677#undef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
678
679/// hasAddressTaken - returns true if there are any uses of this function
680/// other than direct calls or invokes to it.
681bool Function::hasAddressTaken(const User* *PutOffender) const {
682  for (Value::const_use_iterator I = use_begin(), E = use_end(); I != E; ++I) {
683    const User *U = *I;
684    if (isa<BlockAddress>(U))
685      continue;
686    if (!isa<CallInst>(U) && !isa<InvokeInst>(U))
687      return PutOffender ? (*PutOffender = U, true) : true;
688    ImmutableCallSite CS(cast<Instruction>(U));
689    if (!CS.isCallee(I))
690      return PutOffender ? (*PutOffender = U, true) : true;
691  }
692  return false;
693}
694
695bool Function::isDefTriviallyDead() const {
696  // Check the linkage
697  if (!hasLinkOnceLinkage() && !hasLocalLinkage() &&
698      !hasAvailableExternallyLinkage())
699    return false;
700
701  // Check if the function is used by anything other than a blockaddress.
702  for (Value::const_use_iterator I = use_begin(), E = use_end(); I != E; ++I)
703    if (!isa<BlockAddress>(*I))
704      return false;
705
706  return true;
707}
708
709/// callsFunctionThatReturnsTwice - Return true if the function has a call to
710/// setjmp or other function that gcc recognizes as "returning twice".
711bool Function::callsFunctionThatReturnsTwice() const {
712  for (const_inst_iterator
713         I = inst_begin(this), E = inst_end(this); I != E; ++I) {
714    const CallInst* callInst = dyn_cast<CallInst>(&*I);
715    if (!callInst)
716      continue;
717    if (callInst->canReturnTwice())
718      return true;
719  }
720
721  return false;
722}
723