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/Constants.h"
23 #include "llvm/IR/DerivedTypes.h"
24 #include "llvm/IR/InstIterator.h"
25 #include "llvm/IR/IntrinsicInst.h"
26 #include "llvm/IR/LLVMContext.h"
27 #include "llvm/IR/MDBuilder.h"
28 #include "llvm/IR/Metadata.h"
29 #include "llvm/IR/Module.h"
30 #include "llvm/Support/ManagedStatic.h"
31 #include "llvm/Support/RWMutex.h"
32 #include "llvm/Support/StringPool.h"
33 #include "llvm/Support/Threading.h"
34 using namespace llvm;
35 
36 // Explicit instantiations of SymbolTableListTraits since some of the methods
37 // are not in the public header file...
38 template class llvm::SymbolTableListTraits<Argument>;
39 template class llvm::SymbolTableListTraits<BasicBlock>;
40 
41 //===----------------------------------------------------------------------===//
42 // Argument Implementation
43 //===----------------------------------------------------------------------===//
44 
anchor()45 void Argument::anchor() { }
46 
Argument(Type * Ty,const Twine & Name,Function * Par)47 Argument::Argument(Type *Ty, const Twine &Name, Function *Par)
48   : Value(Ty, Value::ArgumentVal) {
49   Parent = nullptr;
50 
51   if (Par)
52     Par->getArgumentList().push_back(this);
53   setName(Name);
54 }
55 
setParent(Function * parent)56 void Argument::setParent(Function *parent) {
57   Parent = parent;
58 }
59 
60 /// getArgNo - Return the index of this formal argument in its containing
61 /// function.  For example in "void foo(int a, float b)" a is 0 and b is 1.
getArgNo() const62 unsigned Argument::getArgNo() const {
63   const Function *F = getParent();
64   assert(F && "Argument is not in a function");
65 
66   Function::const_arg_iterator AI = F->arg_begin();
67   unsigned ArgIdx = 0;
68   for (; &*AI != this; ++AI)
69     ++ArgIdx;
70 
71   return ArgIdx;
72 }
73 
74 /// hasNonNullAttr - Return true if this argument has the nonnull attribute on
75 /// it in its containing function. Also returns true if at least one byte is
76 /// known to be dereferenceable and the pointer is in addrspace(0).
hasNonNullAttr() const77 bool Argument::hasNonNullAttr() const {
78   if (!getType()->isPointerTy()) return false;
79   if (getParent()->getAttributes().
80         hasAttribute(getArgNo()+1, Attribute::NonNull))
81     return true;
82   else if (getDereferenceableBytes() > 0 &&
83            getType()->getPointerAddressSpace() == 0)
84     return true;
85   return false;
86 }
87 
88 /// hasByValAttr - Return true if this argument has the byval attribute on it
89 /// in its containing function.
hasByValAttr() const90 bool Argument::hasByValAttr() const {
91   if (!getType()->isPointerTy()) return false;
92   return getParent()->getAttributes().
93     hasAttribute(getArgNo()+1, Attribute::ByVal);
94 }
95 
96 /// \brief Return true if this argument has the inalloca attribute on it in
97 /// its containing function.
hasInAllocaAttr() const98 bool Argument::hasInAllocaAttr() const {
99   if (!getType()->isPointerTy()) return false;
100   return getParent()->getAttributes().
101     hasAttribute(getArgNo()+1, Attribute::InAlloca);
102 }
103 
hasByValOrInAllocaAttr() const104 bool Argument::hasByValOrInAllocaAttr() const {
105   if (!getType()->isPointerTy()) return false;
106   AttributeSet Attrs = getParent()->getAttributes();
107   return Attrs.hasAttribute(getArgNo() + 1, Attribute::ByVal) ||
108          Attrs.hasAttribute(getArgNo() + 1, Attribute::InAlloca);
109 }
110 
getParamAlignment() const111 unsigned Argument::getParamAlignment() const {
112   assert(getType()->isPointerTy() && "Only pointers have alignments");
113   return getParent()->getParamAlignment(getArgNo()+1);
114 
115 }
116 
getDereferenceableBytes() const117 uint64_t Argument::getDereferenceableBytes() const {
118   assert(getType()->isPointerTy() &&
119          "Only pointers have dereferenceable bytes");
120   return getParent()->getDereferenceableBytes(getArgNo()+1);
121 }
122 
getDereferenceableOrNullBytes() const123 uint64_t Argument::getDereferenceableOrNullBytes() const {
124   assert(getType()->isPointerTy() &&
125          "Only pointers have dereferenceable bytes");
126   return getParent()->getDereferenceableOrNullBytes(getArgNo()+1);
127 }
128 
129 /// hasNestAttr - Return true if this argument has the nest attribute on
130 /// it in its containing function.
hasNestAttr() const131 bool Argument::hasNestAttr() const {
132   if (!getType()->isPointerTy()) return false;
133   return getParent()->getAttributes().
134     hasAttribute(getArgNo()+1, Attribute::Nest);
135 }
136 
137 /// hasNoAliasAttr - Return true if this argument has the noalias attribute on
138 /// it in its containing function.
hasNoAliasAttr() const139 bool Argument::hasNoAliasAttr() const {
140   if (!getType()->isPointerTy()) return false;
141   return getParent()->getAttributes().
142     hasAttribute(getArgNo()+1, Attribute::NoAlias);
143 }
144 
145 /// hasNoCaptureAttr - Return true if this argument has the nocapture attribute
146 /// on it in its containing function.
hasNoCaptureAttr() const147 bool Argument::hasNoCaptureAttr() const {
148   if (!getType()->isPointerTy()) return false;
149   return getParent()->getAttributes().
150     hasAttribute(getArgNo()+1, Attribute::NoCapture);
151 }
152 
153 /// hasSRetAttr - Return true if this argument has the sret attribute on
154 /// it in its containing function.
hasStructRetAttr() const155 bool Argument::hasStructRetAttr() const {
156   if (!getType()->isPointerTy()) return false;
157   return getParent()->getAttributes().
158     hasAttribute(getArgNo()+1, Attribute::StructRet);
159 }
160 
161 /// hasReturnedAttr - Return true if this argument has the returned attribute on
162 /// it in its containing function.
hasReturnedAttr() const163 bool Argument::hasReturnedAttr() const {
164   return getParent()->getAttributes().
165     hasAttribute(getArgNo()+1, Attribute::Returned);
166 }
167 
168 /// hasZExtAttr - Return true if this argument has the zext attribute on it in
169 /// its containing function.
hasZExtAttr() const170 bool Argument::hasZExtAttr() const {
171   return getParent()->getAttributes().
172     hasAttribute(getArgNo()+1, Attribute::ZExt);
173 }
174 
175 /// hasSExtAttr Return true if this argument has the sext attribute on it in its
176 /// containing function.
hasSExtAttr() const177 bool Argument::hasSExtAttr() const {
178   return getParent()->getAttributes().
179     hasAttribute(getArgNo()+1, Attribute::SExt);
180 }
181 
182 /// Return true if this argument has the readonly or readnone attribute on it
183 /// in its containing function.
onlyReadsMemory() const184 bool Argument::onlyReadsMemory() const {
185   return getParent()->getAttributes().
186       hasAttribute(getArgNo()+1, Attribute::ReadOnly) ||
187       getParent()->getAttributes().
188       hasAttribute(getArgNo()+1, Attribute::ReadNone);
189 }
190 
191 /// addAttr - Add attributes to an argument.
addAttr(AttributeSet AS)192 void Argument::addAttr(AttributeSet AS) {
193   assert(AS.getNumSlots() <= 1 &&
194          "Trying to add more than one attribute set to an argument!");
195   AttrBuilder B(AS, AS.getSlotIndex(0));
196   getParent()->addAttributes(getArgNo() + 1,
197                              AttributeSet::get(Parent->getContext(),
198                                                getArgNo() + 1, B));
199 }
200 
201 /// removeAttr - Remove attributes from an argument.
removeAttr(AttributeSet AS)202 void Argument::removeAttr(AttributeSet AS) {
203   assert(AS.getNumSlots() <= 1 &&
204          "Trying to remove more than one attribute set from an argument!");
205   AttrBuilder B(AS, AS.getSlotIndex(0));
206   getParent()->removeAttributes(getArgNo() + 1,
207                                 AttributeSet::get(Parent->getContext(),
208                                                   getArgNo() + 1, B));
209 }
210 
211 //===----------------------------------------------------------------------===//
212 // Helper Methods in Function
213 //===----------------------------------------------------------------------===//
214 
isMaterializable() const215 bool Function::isMaterializable() const {
216   return getGlobalObjectSubClassData() & IsMaterializableBit;
217 }
218 
setIsMaterializable(bool V)219 void Function::setIsMaterializable(bool V) {
220   setGlobalObjectBit(IsMaterializableBit, V);
221 }
222 
getContext() const223 LLVMContext &Function::getContext() const {
224   return getType()->getContext();
225 }
226 
getFunctionType() const227 FunctionType *Function::getFunctionType() const { return Ty; }
228 
isVarArg() const229 bool Function::isVarArg() const {
230   return getFunctionType()->isVarArg();
231 }
232 
getReturnType() const233 Type *Function::getReturnType() const {
234   return getFunctionType()->getReturnType();
235 }
236 
removeFromParent()237 void Function::removeFromParent() {
238   getParent()->getFunctionList().remove(getIterator());
239 }
240 
eraseFromParent()241 void Function::eraseFromParent() {
242   getParent()->getFunctionList().erase(getIterator());
243 }
244 
245 //===----------------------------------------------------------------------===//
246 // Function Implementation
247 //===----------------------------------------------------------------------===//
248 
Function(FunctionType * Ty,LinkageTypes Linkage,const Twine & name,Module * ParentModule)249 Function::Function(FunctionType *Ty, LinkageTypes Linkage, const Twine &name,
250                    Module *ParentModule)
251     : GlobalObject(Ty, Value::FunctionVal,
252                    OperandTraits<Function>::op_begin(this), 0, Linkage, name),
253       Ty(Ty) {
254   assert(FunctionType::isValidReturnType(getReturnType()) &&
255          "invalid return type");
256   setGlobalObjectSubClassData(0);
257   SymTab = new ValueSymbolTable();
258 
259   // If the function has arguments, mark them as lazily built.
260   if (Ty->getNumParams())
261     setValueSubclassData(1);   // Set the "has lazy arguments" bit.
262 
263   if (ParentModule)
264     ParentModule->getFunctionList().push_back(this);
265 
266   // Ensure intrinsics have the right parameter attributes.
267   // Note, the IntID field will have been set in Value::setName if this function
268   // name is a valid intrinsic ID.
269   if (IntID)
270     setAttributes(Intrinsic::getAttributes(getContext(), IntID));
271 }
272 
~Function()273 Function::~Function() {
274   dropAllReferences();    // After this it is safe to delete instructions.
275 
276   // Delete all of the method arguments and unlink from symbol table...
277   ArgumentList.clear();
278   delete SymTab;
279 
280   // Remove the function from the on-the-side GC table.
281   clearGC();
282 }
283 
BuildLazyArguments() const284 void Function::BuildLazyArguments() const {
285   // Create the arguments vector, all arguments start out unnamed.
286   FunctionType *FT = getFunctionType();
287   for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
288     assert(!FT->getParamType(i)->isVoidTy() &&
289            "Cannot have void typed arguments!");
290     ArgumentList.push_back(new Argument(FT->getParamType(i)));
291   }
292 
293   // Clear the lazy arguments bit.
294   unsigned SDC = getSubclassDataFromValue();
295   const_cast<Function*>(this)->setValueSubclassData(SDC &= ~(1<<0));
296 }
297 
arg_size() const298 size_t Function::arg_size() const {
299   return getFunctionType()->getNumParams();
300 }
arg_empty() const301 bool Function::arg_empty() const {
302   return getFunctionType()->getNumParams() == 0;
303 }
304 
setParent(Module * parent)305 void Function::setParent(Module *parent) {
306   Parent = parent;
307 }
308 
309 // dropAllReferences() - This function causes all the subinstructions to "let
310 // go" of all references that they are maintaining.  This allows one to
311 // 'delete' a whole class at a time, even though there may be circular
312 // references... first all references are dropped, and all use counts go to
313 // zero.  Then everything is deleted for real.  Note that no operations are
314 // valid on an object that has "dropped all references", except operator
315 // delete.
316 //
dropAllReferences()317 void Function::dropAllReferences() {
318   setIsMaterializable(false);
319 
320   for (iterator I = begin(), E = end(); I != E; ++I)
321     I->dropAllReferences();
322 
323   // Delete all basic blocks. They are now unused, except possibly by
324   // blockaddresses, but BasicBlock's destructor takes care of those.
325   while (!BasicBlocks.empty())
326     BasicBlocks.begin()->eraseFromParent();
327 
328   // Drop uses of any optional data (real or placeholder).
329   if (getNumOperands()) {
330     User::dropAllReferences();
331     setNumHungOffUseOperands(0);
332     setValueSubclassData(getSubclassDataFromValue() & ~0xe);
333   }
334 
335   // Metadata is stored in a side-table.
336   clearMetadata();
337 }
338 
addAttribute(unsigned i,Attribute::AttrKind attr)339 void Function::addAttribute(unsigned i, Attribute::AttrKind attr) {
340   AttributeSet PAL = getAttributes();
341   PAL = PAL.addAttribute(getContext(), i, attr);
342   setAttributes(PAL);
343 }
344 
addAttributes(unsigned i,AttributeSet attrs)345 void Function::addAttributes(unsigned i, AttributeSet attrs) {
346   AttributeSet PAL = getAttributes();
347   PAL = PAL.addAttributes(getContext(), i, attrs);
348   setAttributes(PAL);
349 }
350 
removeAttributes(unsigned i,AttributeSet attrs)351 void Function::removeAttributes(unsigned i, AttributeSet attrs) {
352   AttributeSet PAL = getAttributes();
353   PAL = PAL.removeAttributes(getContext(), i, attrs);
354   setAttributes(PAL);
355 }
356 
addDereferenceableAttr(unsigned i,uint64_t Bytes)357 void Function::addDereferenceableAttr(unsigned i, uint64_t Bytes) {
358   AttributeSet PAL = getAttributes();
359   PAL = PAL.addDereferenceableAttr(getContext(), i, Bytes);
360   setAttributes(PAL);
361 }
362 
addDereferenceableOrNullAttr(unsigned i,uint64_t Bytes)363 void Function::addDereferenceableOrNullAttr(unsigned i, uint64_t Bytes) {
364   AttributeSet PAL = getAttributes();
365   PAL = PAL.addDereferenceableOrNullAttr(getContext(), i, Bytes);
366   setAttributes(PAL);
367 }
368 
369 // Maintain the GC name for each function in an on-the-side table. This saves
370 // allocating an additional word in Function for programs which do not use GC
371 // (i.e., most programs) at the cost of increased overhead for clients which do
372 // use GC.
373 static DenseMap<const Function*,PooledStringPtr> *GCNames;
374 static StringPool *GCNamePool;
375 static ManagedStatic<sys::SmartRWMutex<true> > GCLock;
376 
hasGC() const377 bool Function::hasGC() const {
378   sys::SmartScopedReader<true> Reader(*GCLock);
379   return GCNames && GCNames->count(this);
380 }
381 
getGC() const382 const char *Function::getGC() const {
383   assert(hasGC() && "Function has no collector");
384   sys::SmartScopedReader<true> Reader(*GCLock);
385   return *(*GCNames)[this];
386 }
387 
setGC(const char * Str)388 void Function::setGC(const char *Str) {
389   sys::SmartScopedWriter<true> Writer(*GCLock);
390   if (!GCNamePool)
391     GCNamePool = new StringPool();
392   if (!GCNames)
393     GCNames = new DenseMap<const Function*,PooledStringPtr>();
394   (*GCNames)[this] = GCNamePool->intern(Str);
395 }
396 
clearGC()397 void Function::clearGC() {
398   sys::SmartScopedWriter<true> Writer(*GCLock);
399   if (GCNames) {
400     GCNames->erase(this);
401     if (GCNames->empty()) {
402       delete GCNames;
403       GCNames = nullptr;
404       if (GCNamePool->empty()) {
405         delete GCNamePool;
406         GCNamePool = nullptr;
407       }
408     }
409   }
410 }
411 
412 /// Copy all additional attributes (those not needed to create a Function) from
413 /// the Function Src to this one.
copyAttributesFrom(const GlobalValue * Src)414 void Function::copyAttributesFrom(const GlobalValue *Src) {
415   GlobalObject::copyAttributesFrom(Src);
416   const Function *SrcF = dyn_cast<Function>(Src);
417   if (!SrcF)
418     return;
419 
420   setCallingConv(SrcF->getCallingConv());
421   setAttributes(SrcF->getAttributes());
422   if (SrcF->hasGC())
423     setGC(SrcF->getGC());
424   else
425     clearGC();
426   if (SrcF->hasPersonalityFn())
427     setPersonalityFn(SrcF->getPersonalityFn());
428   if (SrcF->hasPrefixData())
429     setPrefixData(SrcF->getPrefixData());
430   if (SrcF->hasPrologueData())
431     setPrologueData(SrcF->getPrologueData());
432 }
433 
434 /// \brief This does the actual lookup of an intrinsic ID which
435 /// matches the given function name.
lookupIntrinsicID(const ValueName * ValName)436 static Intrinsic::ID lookupIntrinsicID(const ValueName *ValName) {
437   unsigned Len = ValName->getKeyLength();
438   const char *Name = ValName->getKeyData();
439 
440 #define GET_FUNCTION_RECOGNIZER
441 #include "llvm/IR/Intrinsics.gen"
442 #undef GET_FUNCTION_RECOGNIZER
443 
444   return Intrinsic::not_intrinsic;
445 }
446 
recalculateIntrinsicID()447 void Function::recalculateIntrinsicID() {
448   const ValueName *ValName = this->getValueName();
449   if (!ValName || !isIntrinsic()) {
450     IntID = Intrinsic::not_intrinsic;
451     return;
452   }
453   IntID = lookupIntrinsicID(ValName);
454 }
455 
456 /// Returns a stable mangling for the type specified for use in the name
457 /// mangling scheme used by 'any' types in intrinsic signatures.  The mangling
458 /// of named types is simply their name.  Manglings for unnamed types consist
459 /// of a prefix ('p' for pointers, 'a' for arrays, 'f_' for functions)
460 /// combined with the mangling of their component types.  A vararg function
461 /// type will have a suffix of 'vararg'.  Since function types can contain
462 /// other function types, we close a function type mangling with suffix 'f'
463 /// which can't be confused with it's prefix.  This ensures we don't have
464 /// collisions between two unrelated function types. Otherwise, you might
465 /// parse ffXX as f(fXX) or f(fX)X.  (X is a placeholder for any other type.)
466 /// Manglings of integers, floats, and vectors ('i', 'f', and 'v' prefix in most
467 /// cases) fall back to the MVT codepath, where they could be mangled to
468 /// 'x86mmx', for example; matching on derived types is not sufficient to mangle
469 /// everything.
getMangledTypeStr(Type * Ty)470 static std::string getMangledTypeStr(Type* Ty) {
471   std::string Result;
472   if (PointerType* PTyp = dyn_cast<PointerType>(Ty)) {
473     Result += "p" + llvm::utostr(PTyp->getAddressSpace()) +
474       getMangledTypeStr(PTyp->getElementType());
475   } else if (ArrayType* ATyp = dyn_cast<ArrayType>(Ty)) {
476     Result += "a" + llvm::utostr(ATyp->getNumElements()) +
477       getMangledTypeStr(ATyp->getElementType());
478   } else if (StructType* STyp = dyn_cast<StructType>(Ty)) {
479     assert(!STyp->isLiteral() && "TODO: implement literal types");
480     Result += STyp->getName();
481   } else if (FunctionType* FT = dyn_cast<FunctionType>(Ty)) {
482     Result += "f_" + getMangledTypeStr(FT->getReturnType());
483     for (size_t i = 0; i < FT->getNumParams(); i++)
484       Result += getMangledTypeStr(FT->getParamType(i));
485     if (FT->isVarArg())
486       Result += "vararg";
487     // Ensure nested function types are distinguishable.
488     Result += "f";
489   } else if (isa<VectorType>(Ty))
490     Result += "v" + utostr(Ty->getVectorNumElements()) +
491       getMangledTypeStr(Ty->getVectorElementType());
492   else if (Ty)
493     Result += EVT::getEVT(Ty).getEVTString();
494   return Result;
495 }
496 
getName(ID id,ArrayRef<Type * > Tys)497 std::string Intrinsic::getName(ID id, ArrayRef<Type*> Tys) {
498   assert(id < num_intrinsics && "Invalid intrinsic ID!");
499   static const char * const Table[] = {
500     "not_intrinsic",
501 #define GET_INTRINSIC_NAME_TABLE
502 #include "llvm/IR/Intrinsics.gen"
503 #undef GET_INTRINSIC_NAME_TABLE
504   };
505   if (Tys.empty())
506     return Table[id];
507   std::string Result(Table[id]);
508   for (unsigned i = 0; i < Tys.size(); ++i) {
509     Result += "." + getMangledTypeStr(Tys[i]);
510   }
511   return Result;
512 }
513 
514 
515 /// IIT_Info - These are enumerators that describe the entries returned by the
516 /// getIntrinsicInfoTableEntries function.
517 ///
518 /// NOTE: This must be kept in synch with the copy in TblGen/IntrinsicEmitter!
519 enum IIT_Info {
520   // Common values should be encoded with 0-15.
521   IIT_Done = 0,
522   IIT_I1   = 1,
523   IIT_I8   = 2,
524   IIT_I16  = 3,
525   IIT_I32  = 4,
526   IIT_I64  = 5,
527   IIT_F16  = 6,
528   IIT_F32  = 7,
529   IIT_F64  = 8,
530   IIT_V2   = 9,
531   IIT_V4   = 10,
532   IIT_V8   = 11,
533   IIT_V16  = 12,
534   IIT_V32  = 13,
535   IIT_PTR  = 14,
536   IIT_ARG  = 15,
537 
538   // Values from 16+ are only encodable with the inefficient encoding.
539   IIT_V64  = 16,
540   IIT_MMX  = 17,
541   IIT_TOKEN = 18,
542   IIT_METADATA = 19,
543   IIT_EMPTYSTRUCT = 20,
544   IIT_STRUCT2 = 21,
545   IIT_STRUCT3 = 22,
546   IIT_STRUCT4 = 23,
547   IIT_STRUCT5 = 24,
548   IIT_EXTEND_ARG = 25,
549   IIT_TRUNC_ARG = 26,
550   IIT_ANYPTR = 27,
551   IIT_V1   = 28,
552   IIT_VARARG = 29,
553   IIT_HALF_VEC_ARG = 30,
554   IIT_SAME_VEC_WIDTH_ARG = 31,
555   IIT_PTR_TO_ARG = 32,
556   IIT_VEC_OF_PTRS_TO_ELT = 33,
557   IIT_I128 = 34,
558   IIT_V512 = 35,
559   IIT_V1024 = 36
560 };
561 
562 
DecodeIITType(unsigned & NextElt,ArrayRef<unsigned char> Infos,SmallVectorImpl<Intrinsic::IITDescriptor> & OutputTable)563 static void DecodeIITType(unsigned &NextElt, ArrayRef<unsigned char> Infos,
564                       SmallVectorImpl<Intrinsic::IITDescriptor> &OutputTable) {
565   IIT_Info Info = IIT_Info(Infos[NextElt++]);
566   unsigned StructElts = 2;
567   using namespace Intrinsic;
568 
569   switch (Info) {
570   case IIT_Done:
571     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Void, 0));
572     return;
573   case IIT_VARARG:
574     OutputTable.push_back(IITDescriptor::get(IITDescriptor::VarArg, 0));
575     return;
576   case IIT_MMX:
577     OutputTable.push_back(IITDescriptor::get(IITDescriptor::MMX, 0));
578     return;
579   case IIT_TOKEN:
580     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Token, 0));
581     return;
582   case IIT_METADATA:
583     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Metadata, 0));
584     return;
585   case IIT_F16:
586     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Half, 0));
587     return;
588   case IIT_F32:
589     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Float, 0));
590     return;
591   case IIT_F64:
592     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Double, 0));
593     return;
594   case IIT_I1:
595     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 1));
596     return;
597   case IIT_I8:
598     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 8));
599     return;
600   case IIT_I16:
601     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer,16));
602     return;
603   case IIT_I32:
604     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 32));
605     return;
606   case IIT_I64:
607     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 64));
608     return;
609   case IIT_I128:
610     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Integer, 128));
611     return;
612   case IIT_V1:
613     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 1));
614     DecodeIITType(NextElt, Infos, OutputTable);
615     return;
616   case IIT_V2:
617     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 2));
618     DecodeIITType(NextElt, Infos, OutputTable);
619     return;
620   case IIT_V4:
621     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 4));
622     DecodeIITType(NextElt, Infos, OutputTable);
623     return;
624   case IIT_V8:
625     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 8));
626     DecodeIITType(NextElt, Infos, OutputTable);
627     return;
628   case IIT_V16:
629     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 16));
630     DecodeIITType(NextElt, Infos, OutputTable);
631     return;
632   case IIT_V32:
633     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 32));
634     DecodeIITType(NextElt, Infos, OutputTable);
635     return;
636   case IIT_V64:
637     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 64));
638     DecodeIITType(NextElt, Infos, OutputTable);
639     return;
640   case IIT_V512:
641     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 512));
642     DecodeIITType(NextElt, Infos, OutputTable);
643     return;
644   case IIT_V1024:
645     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Vector, 1024));
646     DecodeIITType(NextElt, Infos, OutputTable);
647     return;
648   case IIT_PTR:
649     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer, 0));
650     DecodeIITType(NextElt, Infos, OutputTable);
651     return;
652   case IIT_ANYPTR: {  // [ANYPTR addrspace, subtype]
653     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Pointer,
654                                              Infos[NextElt++]));
655     DecodeIITType(NextElt, Infos, OutputTable);
656     return;
657   }
658   case IIT_ARG: {
659     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
660     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Argument, ArgInfo));
661     return;
662   }
663   case IIT_EXTEND_ARG: {
664     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
665     OutputTable.push_back(IITDescriptor::get(IITDescriptor::ExtendArgument,
666                                              ArgInfo));
667     return;
668   }
669   case IIT_TRUNC_ARG: {
670     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
671     OutputTable.push_back(IITDescriptor::get(IITDescriptor::TruncArgument,
672                                              ArgInfo));
673     return;
674   }
675   case IIT_HALF_VEC_ARG: {
676     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
677     OutputTable.push_back(IITDescriptor::get(IITDescriptor::HalfVecArgument,
678                                              ArgInfo));
679     return;
680   }
681   case IIT_SAME_VEC_WIDTH_ARG: {
682     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
683     OutputTable.push_back(IITDescriptor::get(IITDescriptor::SameVecWidthArgument,
684                                              ArgInfo));
685     return;
686   }
687   case IIT_PTR_TO_ARG: {
688     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
689     OutputTable.push_back(IITDescriptor::get(IITDescriptor::PtrToArgument,
690                                              ArgInfo));
691     return;
692   }
693   case IIT_VEC_OF_PTRS_TO_ELT: {
694     unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
695     OutputTable.push_back(IITDescriptor::get(IITDescriptor::VecOfPtrsToElt,
696                                              ArgInfo));
697     return;
698   }
699   case IIT_EMPTYSTRUCT:
700     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct, 0));
701     return;
702   case IIT_STRUCT5: ++StructElts; // FALL THROUGH.
703   case IIT_STRUCT4: ++StructElts; // FALL THROUGH.
704   case IIT_STRUCT3: ++StructElts; // FALL THROUGH.
705   case IIT_STRUCT2: {
706     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct,StructElts));
707 
708     for (unsigned i = 0; i != StructElts; ++i)
709       DecodeIITType(NextElt, Infos, OutputTable);
710     return;
711   }
712   }
713   llvm_unreachable("unhandled");
714 }
715 
716 
717 #define GET_INTRINSIC_GENERATOR_GLOBAL
718 #include "llvm/IR/Intrinsics.gen"
719 #undef GET_INTRINSIC_GENERATOR_GLOBAL
720 
getIntrinsicInfoTableEntries(ID id,SmallVectorImpl<IITDescriptor> & T)721 void Intrinsic::getIntrinsicInfoTableEntries(ID id,
722                                              SmallVectorImpl<IITDescriptor> &T){
723   // Check to see if the intrinsic's type was expressible by the table.
724   unsigned TableVal = IIT_Table[id-1];
725 
726   // Decode the TableVal into an array of IITValues.
727   SmallVector<unsigned char, 8> IITValues;
728   ArrayRef<unsigned char> IITEntries;
729   unsigned NextElt = 0;
730   if ((TableVal >> 31) != 0) {
731     // This is an offset into the IIT_LongEncodingTable.
732     IITEntries = IIT_LongEncodingTable;
733 
734     // Strip sentinel bit.
735     NextElt = (TableVal << 1) >> 1;
736   } else {
737     // Decode the TableVal into an array of IITValues.  If the entry was encoded
738     // into a single word in the table itself, decode it now.
739     do {
740       IITValues.push_back(TableVal & 0xF);
741       TableVal >>= 4;
742     } while (TableVal);
743 
744     IITEntries = IITValues;
745     NextElt = 0;
746   }
747 
748   // Okay, decode the table into the output vector of IITDescriptors.
749   DecodeIITType(NextElt, IITEntries, T);
750   while (NextElt != IITEntries.size() && IITEntries[NextElt] != 0)
751     DecodeIITType(NextElt, IITEntries, T);
752 }
753 
754 
DecodeFixedType(ArrayRef<Intrinsic::IITDescriptor> & Infos,ArrayRef<Type * > Tys,LLVMContext & Context)755 static Type *DecodeFixedType(ArrayRef<Intrinsic::IITDescriptor> &Infos,
756                              ArrayRef<Type*> Tys, LLVMContext &Context) {
757   using namespace Intrinsic;
758   IITDescriptor D = Infos.front();
759   Infos = Infos.slice(1);
760 
761   switch (D.Kind) {
762   case IITDescriptor::Void: return Type::getVoidTy(Context);
763   case IITDescriptor::VarArg: return Type::getVoidTy(Context);
764   case IITDescriptor::MMX: return Type::getX86_MMXTy(Context);
765   case IITDescriptor::Token: return Type::getTokenTy(Context);
766   case IITDescriptor::Metadata: return Type::getMetadataTy(Context);
767   case IITDescriptor::Half: return Type::getHalfTy(Context);
768   case IITDescriptor::Float: return Type::getFloatTy(Context);
769   case IITDescriptor::Double: return Type::getDoubleTy(Context);
770 
771   case IITDescriptor::Integer:
772     return IntegerType::get(Context, D.Integer_Width);
773   case IITDescriptor::Vector:
774     return VectorType::get(DecodeFixedType(Infos, Tys, Context),D.Vector_Width);
775   case IITDescriptor::Pointer:
776     return PointerType::get(DecodeFixedType(Infos, Tys, Context),
777                             D.Pointer_AddressSpace);
778   case IITDescriptor::Struct: {
779     Type *Elts[5];
780     assert(D.Struct_NumElements <= 5 && "Can't handle this yet");
781     for (unsigned i = 0, e = D.Struct_NumElements; i != e; ++i)
782       Elts[i] = DecodeFixedType(Infos, Tys, Context);
783     return StructType::get(Context, makeArrayRef(Elts,D.Struct_NumElements));
784   }
785 
786   case IITDescriptor::Argument:
787     return Tys[D.getArgumentNumber()];
788   case IITDescriptor::ExtendArgument: {
789     Type *Ty = Tys[D.getArgumentNumber()];
790     if (VectorType *VTy = dyn_cast<VectorType>(Ty))
791       return VectorType::getExtendedElementVectorType(VTy);
792 
793     return IntegerType::get(Context, 2 * cast<IntegerType>(Ty)->getBitWidth());
794   }
795   case IITDescriptor::TruncArgument: {
796     Type *Ty = Tys[D.getArgumentNumber()];
797     if (VectorType *VTy = dyn_cast<VectorType>(Ty))
798       return VectorType::getTruncatedElementVectorType(VTy);
799 
800     IntegerType *ITy = cast<IntegerType>(Ty);
801     assert(ITy->getBitWidth() % 2 == 0);
802     return IntegerType::get(Context, ITy->getBitWidth() / 2);
803   }
804   case IITDescriptor::HalfVecArgument:
805     return VectorType::getHalfElementsVectorType(cast<VectorType>(
806                                                   Tys[D.getArgumentNumber()]));
807   case IITDescriptor::SameVecWidthArgument: {
808     Type *EltTy = DecodeFixedType(Infos, Tys, Context);
809     Type *Ty = Tys[D.getArgumentNumber()];
810     if (VectorType *VTy = dyn_cast<VectorType>(Ty)) {
811       return VectorType::get(EltTy, VTy->getNumElements());
812     }
813     llvm_unreachable("unhandled");
814   }
815   case IITDescriptor::PtrToArgument: {
816     Type *Ty = Tys[D.getArgumentNumber()];
817     return PointerType::getUnqual(Ty);
818   }
819   case IITDescriptor::VecOfPtrsToElt: {
820     Type *Ty = Tys[D.getArgumentNumber()];
821     VectorType *VTy = dyn_cast<VectorType>(Ty);
822     if (!VTy)
823       llvm_unreachable("Expected an argument of Vector Type");
824     Type *EltTy = VTy->getVectorElementType();
825     return VectorType::get(PointerType::getUnqual(EltTy),
826                            VTy->getNumElements());
827   }
828  }
829   llvm_unreachable("unhandled");
830 }
831 
832 
833 
getType(LLVMContext & Context,ID id,ArrayRef<Type * > Tys)834 FunctionType *Intrinsic::getType(LLVMContext &Context,
835                                  ID id, ArrayRef<Type*> Tys) {
836   SmallVector<IITDescriptor, 8> Table;
837   getIntrinsicInfoTableEntries(id, Table);
838 
839   ArrayRef<IITDescriptor> TableRef = Table;
840   Type *ResultTy = DecodeFixedType(TableRef, Tys, Context);
841 
842   SmallVector<Type*, 8> ArgTys;
843   while (!TableRef.empty())
844     ArgTys.push_back(DecodeFixedType(TableRef, Tys, Context));
845 
846   // DecodeFixedType returns Void for IITDescriptor::Void and IITDescriptor::VarArg
847   // If we see void type as the type of the last argument, it is vararg intrinsic
848   if (!ArgTys.empty() && ArgTys.back()->isVoidTy()) {
849     ArgTys.pop_back();
850     return FunctionType::get(ResultTy, ArgTys, true);
851   }
852   return FunctionType::get(ResultTy, ArgTys, false);
853 }
854 
isOverloaded(ID id)855 bool Intrinsic::isOverloaded(ID id) {
856 #define GET_INTRINSIC_OVERLOAD_TABLE
857 #include "llvm/IR/Intrinsics.gen"
858 #undef GET_INTRINSIC_OVERLOAD_TABLE
859 }
860 
isLeaf(ID id)861 bool Intrinsic::isLeaf(ID id) {
862   switch (id) {
863   default:
864     return true;
865 
866   case Intrinsic::experimental_gc_statepoint:
867   case Intrinsic::experimental_patchpoint_void:
868   case Intrinsic::experimental_patchpoint_i64:
869     return false;
870   }
871 }
872 
873 /// This defines the "Intrinsic::getAttributes(ID id)" method.
874 #define GET_INTRINSIC_ATTRIBUTES
875 #include "llvm/IR/Intrinsics.gen"
876 #undef GET_INTRINSIC_ATTRIBUTES
877 
getDeclaration(Module * M,ID id,ArrayRef<Type * > Tys)878 Function *Intrinsic::getDeclaration(Module *M, ID id, ArrayRef<Type*> Tys) {
879   // There can never be multiple globals with the same name of different types,
880   // because intrinsics must be a specific type.
881   return
882     cast<Function>(M->getOrInsertFunction(getName(id, Tys),
883                                           getType(M->getContext(), id, Tys)));
884 }
885 
886 // This defines the "Intrinsic::getIntrinsicForGCCBuiltin()" method.
887 #define GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
888 #include "llvm/IR/Intrinsics.gen"
889 #undef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
890 
891 // This defines the "Intrinsic::getIntrinsicForMSBuiltin()" method.
892 #define GET_LLVM_INTRINSIC_FOR_MS_BUILTIN
893 #include "llvm/IR/Intrinsics.gen"
894 #undef GET_LLVM_INTRINSIC_FOR_MS_BUILTIN
895 
896 /// hasAddressTaken - returns true if there are any uses of this function
897 /// other than direct calls or invokes to it.
hasAddressTaken(const User ** PutOffender) const898 bool Function::hasAddressTaken(const User* *PutOffender) const {
899   for (const Use &U : uses()) {
900     const User *FU = U.getUser();
901     if (isa<BlockAddress>(FU))
902       continue;
903     if (!isa<CallInst>(FU) && !isa<InvokeInst>(FU))
904       return PutOffender ? (*PutOffender = FU, true) : true;
905     ImmutableCallSite CS(cast<Instruction>(FU));
906     if (!CS.isCallee(&U))
907       return PutOffender ? (*PutOffender = FU, true) : true;
908   }
909   return false;
910 }
911 
isDefTriviallyDead() const912 bool Function::isDefTriviallyDead() const {
913   // Check the linkage
914   if (!hasLinkOnceLinkage() && !hasLocalLinkage() &&
915       !hasAvailableExternallyLinkage())
916     return false;
917 
918   // Check if the function is used by anything other than a blockaddress.
919   for (const User *U : users())
920     if (!isa<BlockAddress>(U))
921       return false;
922 
923   return true;
924 }
925 
926 /// callsFunctionThatReturnsTwice - Return true if the function has a call to
927 /// setjmp or other function that gcc recognizes as "returning twice".
callsFunctionThatReturnsTwice() const928 bool Function::callsFunctionThatReturnsTwice() const {
929   for (const_inst_iterator
930          I = inst_begin(this), E = inst_end(this); I != E; ++I) {
931     ImmutableCallSite CS(&*I);
932     if (CS && CS.hasFnAttr(Attribute::ReturnsTwice))
933       return true;
934   }
935 
936   return false;
937 }
938 
getPersonalityFn() const939 Constant *Function::getPersonalityFn() const {
940   assert(hasPersonalityFn() && getNumOperands());
941   return cast<Constant>(Op<0>());
942 }
943 
setPersonalityFn(Constant * Fn)944 void Function::setPersonalityFn(Constant *Fn) {
945   if (Fn)
946     setHungoffOperand<0>(Fn);
947   setValueSubclassDataBit(3, Fn != nullptr);
948 }
949 
getPrefixData() const950 Constant *Function::getPrefixData() const {
951   assert(hasPrefixData() && getNumOperands());
952   return cast<Constant>(Op<1>());
953 }
954 
setPrefixData(Constant * PrefixData)955 void Function::setPrefixData(Constant *PrefixData) {
956   if (PrefixData)
957     setHungoffOperand<1>(PrefixData);
958   setValueSubclassDataBit(1, PrefixData != nullptr);
959 }
960 
getPrologueData() const961 Constant *Function::getPrologueData() const {
962   assert(hasPrologueData() && getNumOperands());
963   return cast<Constant>(Op<2>());
964 }
965 
setPrologueData(Constant * PrologueData)966 void Function::setPrologueData(Constant *PrologueData) {
967   if (PrologueData)
968     setHungoffOperand<2>(PrologueData);
969   setValueSubclassDataBit(2, PrologueData != nullptr);
970 }
971 
allocHungoffUselist()972 void Function::allocHungoffUselist() {
973   // If we've already allocated a uselist, stop here.
974   if (getNumOperands())
975     return;
976 
977   allocHungoffUses(3, /*IsPhi=*/ false);
978   setNumHungOffUseOperands(3);
979 
980   // Initialize the uselist with placeholder operands to allow traversal.
981   auto *CPN = ConstantPointerNull::get(Type::getInt1PtrTy(getContext(), 0));
982   Op<0>().set(CPN);
983   Op<1>().set(CPN);
984   Op<2>().set(CPN);
985 }
986 
987 template <int Idx>
setHungoffOperand(Constant * C)988 void Function::setHungoffOperand(Constant *C) {
989   assert(C && "Cannot set hungoff operand to nullptr");
990   allocHungoffUselist();
991   Op<Idx>().set(C);
992 }
993 
setValueSubclassDataBit(unsigned Bit,bool On)994 void Function::setValueSubclassDataBit(unsigned Bit, bool On) {
995   assert(Bit < 16 && "SubclassData contains only 16 bits");
996   if (On)
997     setValueSubclassData(getSubclassDataFromValue() | (1 << Bit));
998   else
999     setValueSubclassData(getSubclassDataFromValue() & ~(1 << Bit));
1000 }
1001 
setEntryCount(uint64_t Count)1002 void Function::setEntryCount(uint64_t Count) {
1003   MDBuilder MDB(getContext());
1004   setMetadata(LLVMContext::MD_prof, MDB.createFunctionEntryCount(Count));
1005 }
1006 
getEntryCount() const1007 Optional<uint64_t> Function::getEntryCount() const {
1008   MDNode *MD = getMetadata(LLVMContext::MD_prof);
1009   if (MD && MD->getOperand(0))
1010     if (MDString *MDS = dyn_cast<MDString>(MD->getOperand(0)))
1011       if (MDS->getString().equals("function_entry_count")) {
1012         ConstantInt *CI = mdconst::extract<ConstantInt>(MD->getOperand(1));
1013         return CI->getValue().getZExtValue();
1014       }
1015   return None;
1016 }
1017