1 //===-- Type.cpp - Implement the Type class -------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Type class for the VMCore library.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/AbstractTypeUser.h"
15 #include "llvm/DerivedTypes.h"
16 #include "llvm/SymbolTable.h"
17 #include "llvm/Constants.h"
18 #include "Support/DepthFirstIterator.h"
19 #include "Support/StringExtras.h"
20 #include "Support/STLExtras.h"
25 // DEBUG_MERGE_TYPES - Enable this #define to see how and when derived types are
26 // created and later destroyed, all in an effort to make sure that there is only
27 // a single canonical version of a type.
29 //#define DEBUG_MERGE_TYPES 1
31 AbstractTypeUser::~AbstractTypeUser() {}
33 //===----------------------------------------------------------------------===//
34 // Type Class Implementation
35 //===----------------------------------------------------------------------===//
37 // Concrete/Abstract TypeDescriptions - We lazily calculate type descriptions
38 // for types as they are needed. Because resolution of types must invalidate
39 // all of the abstract type descriptions, we keep them in a seperate map to make
41 static std::map<const Type*, std::string> ConcreteTypeDescriptions;
42 static std::map<const Type*, std::string> AbstractTypeDescriptions;
44 Type::Type( const std::string& name, TypeID id )
45 : RefCount(0), ForwardType(0) {
47 ConcreteTypeDescriptions[this] = name;
52 const Type *Type::getPrimitiveType(TypeID IDNumber) {
54 case VoidTyID : return VoidTy;
55 case BoolTyID : return BoolTy;
56 case UByteTyID : return UByteTy;
57 case SByteTyID : return SByteTy;
58 case UShortTyID: return UShortTy;
59 case ShortTyID : return ShortTy;
60 case UIntTyID : return UIntTy;
61 case IntTyID : return IntTy;
62 case ULongTyID : return ULongTy;
63 case LongTyID : return LongTy;
64 case FloatTyID : return FloatTy;
65 case DoubleTyID: return DoubleTy;
66 case LabelTyID : return LabelTy;
72 // isLosslesslyConvertibleTo - Return true if this type can be converted to
73 // 'Ty' without any reinterpretation of bits. For example, uint to int.
75 bool Type::isLosslesslyConvertibleTo(const Type *Ty) const {
76 if (this == Ty) return true;
77 if ((!isPrimitiveType() && !isa<PointerType>(this)) ||
78 (!isa<PointerType>(Ty) && !Ty->isPrimitiveType())) return false;
80 if (getTypeID() == Ty->getTypeID())
81 return true; // Handles identity cast, and cast of differing pointer types
83 // Now we know that they are two differing primitive or pointer types
84 switch (getTypeID()) {
85 case Type::UByteTyID: return Ty == Type::SByteTy;
86 case Type::SByteTyID: return Ty == Type::UByteTy;
87 case Type::UShortTyID: return Ty == Type::ShortTy;
88 case Type::ShortTyID: return Ty == Type::UShortTy;
89 case Type::UIntTyID: return Ty == Type::IntTy;
90 case Type::IntTyID: return Ty == Type::UIntTy;
91 case Type::ULongTyID: return Ty == Type::LongTy;
92 case Type::LongTyID: return Ty == Type::ULongTy;
93 case Type::PointerTyID: return isa<PointerType>(Ty);
95 return false; // Other types have no identity values
99 /// getUnsignedVersion - If this is an integer type, return the unsigned
100 /// variant of this type. For example int -> uint.
101 const Type *Type::getUnsignedVersion() const {
102 switch (getTypeID()) {
104 assert(isInteger()&&"Type::getUnsignedVersion is only valid for integers!");
105 case Type::UByteTyID:
106 case Type::SByteTyID: return Type::UByteTy;
107 case Type::UShortTyID:
108 case Type::ShortTyID: return Type::UShortTy;
110 case Type::IntTyID: return Type::UIntTy;
111 case Type::ULongTyID:
112 case Type::LongTyID: return Type::ULongTy;
116 /// getSignedVersion - If this is an integer type, return the signed variant
117 /// of this type. For example uint -> int.
118 const Type *Type::getSignedVersion() const {
119 switch (getTypeID()) {
121 assert(isInteger() && "Type::getSignedVersion is only valid for integers!");
122 case Type::UByteTyID:
123 case Type::SByteTyID: return Type::SByteTy;
124 case Type::UShortTyID:
125 case Type::ShortTyID: return Type::ShortTy;
127 case Type::IntTyID: return Type::IntTy;
128 case Type::ULongTyID:
129 case Type::LongTyID: return Type::LongTy;
134 // getPrimitiveSize - Return the basic size of this type if it is a primitive
135 // type. These are fixed by LLVM and are not target dependent. This will
136 // return zero if the type does not have a size or is not a primitive type.
138 unsigned Type::getPrimitiveSize() const {
139 switch (getTypeID()) {
140 #define HANDLE_PRIM_TYPE(TY,SIZE) case TY##TyID: return SIZE;
141 #include "llvm/Type.def"
146 /// isSizedDerivedType - Derived types like structures and arrays are sized
147 /// iff all of the members of the type are sized as well. Since asking for
148 /// their size is relatively uncommon, move this operation out of line.
149 bool Type::isSizedDerivedType() const {
150 if (const ArrayType *ATy = dyn_cast<ArrayType>(this))
151 return ATy->getElementType()->isSized();
153 if (!isa<StructType>(this)) return false;
155 // Okay, our struct is sized if all of the elements are...
156 for (subtype_iterator I = subtype_begin(), E = subtype_end(); I != E; ++I)
157 if (!(*I)->isSized()) return false;
162 /// getForwardedTypeInternal - This method is used to implement the union-find
163 /// algorithm for when a type is being forwarded to another type.
164 const Type *Type::getForwardedTypeInternal() const {
165 assert(ForwardType && "This type is not being forwarded to another type!");
167 // Check to see if the forwarded type has been forwarded on. If so, collapse
168 // the forwarding links.
169 const Type *RealForwardedType = ForwardType->getForwardedType();
170 if (!RealForwardedType)
171 return ForwardType; // No it's not forwarded again
173 // Yes, it is forwarded again. First thing, add the reference to the new
175 if (RealForwardedType->isAbstract())
176 cast<DerivedType>(RealForwardedType)->addRef();
178 // Now drop the old reference. This could cause ForwardType to get deleted.
179 cast<DerivedType>(ForwardType)->dropRef();
181 // Return the updated type.
182 ForwardType = RealForwardedType;
186 // getTypeDescription - This is a recursive function that walks a type hierarchy
187 // calculating the description for a type.
189 static std::string getTypeDescription(const Type *Ty,
190 std::vector<const Type *> &TypeStack) {
191 if (isa<OpaqueType>(Ty)) { // Base case for the recursion
192 std::map<const Type*, std::string>::iterator I =
193 AbstractTypeDescriptions.lower_bound(Ty);
194 if (I != AbstractTypeDescriptions.end() && I->first == Ty)
196 std::string Desc = "opaque";
197 AbstractTypeDescriptions.insert(std::make_pair(Ty, Desc));
201 if (!Ty->isAbstract()) { // Base case for the recursion
202 std::map<const Type*, std::string>::iterator I =
203 ConcreteTypeDescriptions.find(Ty);
204 if (I != ConcreteTypeDescriptions.end()) return I->second;
207 // Check to see if the Type is already on the stack...
208 unsigned Slot = 0, CurSize = TypeStack.size();
209 while (Slot < CurSize && TypeStack[Slot] != Ty) ++Slot; // Scan for type
211 // This is another base case for the recursion. In this case, we know
212 // that we have looped back to a type that we have previously visited.
213 // Generate the appropriate upreference to handle this.
216 return "\\" + utostr(CurSize-Slot); // Here's the upreference
218 // Recursive case: derived types...
220 TypeStack.push_back(Ty); // Add us to the stack..
222 switch (Ty->getTypeID()) {
223 case Type::FunctionTyID: {
224 const FunctionType *FTy = cast<FunctionType>(Ty);
225 Result = getTypeDescription(FTy->getReturnType(), TypeStack) + " (";
226 for (FunctionType::param_iterator I = FTy->param_begin(),
227 E = FTy->param_end(); I != E; ++I) {
228 if (I != FTy->param_begin())
230 Result += getTypeDescription(*I, TypeStack);
232 if (FTy->isVarArg()) {
233 if (FTy->getNumParams()) Result += ", ";
239 case Type::StructTyID: {
240 const StructType *STy = cast<StructType>(Ty);
242 for (StructType::element_iterator I = STy->element_begin(),
243 E = STy->element_end(); I != E; ++I) {
244 if (I != STy->element_begin())
246 Result += getTypeDescription(*I, TypeStack);
251 case Type::PointerTyID: {
252 const PointerType *PTy = cast<PointerType>(Ty);
253 Result = getTypeDescription(PTy->getElementType(), TypeStack) + " *";
256 case Type::ArrayTyID: {
257 const ArrayType *ATy = cast<ArrayType>(Ty);
258 unsigned NumElements = ATy->getNumElements();
260 Result += utostr(NumElements) + " x ";
261 Result += getTypeDescription(ATy->getElementType(), TypeStack) + "]";
266 assert(0 && "Unhandled type in getTypeDescription!");
269 TypeStack.pop_back(); // Remove self from stack...
276 static const std::string &getOrCreateDesc(std::map<const Type*,std::string>&Map,
278 std::map<const Type*, std::string>::iterator I = Map.find(Ty);
279 if (I != Map.end()) return I->second;
281 std::vector<const Type *> TypeStack;
282 return Map[Ty] = getTypeDescription(Ty, TypeStack);
286 const std::string &Type::getDescription() const {
288 return getOrCreateDesc(AbstractTypeDescriptions, this);
290 return getOrCreateDesc(ConcreteTypeDescriptions, this);
294 bool StructType::indexValid(const Value *V) const {
295 // Structure indexes require unsigned integer constants.
296 if (V->getType() == Type::UIntTy)
297 if (const ConstantUInt *CU = dyn_cast<ConstantUInt>(V))
298 return CU->getValue() < ContainedTys.size();
302 // getTypeAtIndex - Given an index value into the type, return the type of the
303 // element. For a structure type, this must be a constant value...
305 const Type *StructType::getTypeAtIndex(const Value *V) const {
306 assert(indexValid(V) && "Invalid structure index!");
307 unsigned Idx = (unsigned)cast<ConstantUInt>(V)->getValue();
308 return ContainedTys[Idx];
312 //===----------------------------------------------------------------------===//
313 // Static 'Type' data
314 //===----------------------------------------------------------------------===//
317 struct PrimType : public Type {
318 PrimType(const char *S, TypeID ID) : Type(S, ID) {}
322 static PrimType TheVoidTy ("void" , Type::VoidTyID);
323 static PrimType TheBoolTy ("bool" , Type::BoolTyID);
324 static PrimType TheSByteTy ("sbyte" , Type::SByteTyID);
325 static PrimType TheUByteTy ("ubyte" , Type::UByteTyID);
326 static PrimType TheShortTy ("short" , Type::ShortTyID);
327 static PrimType TheUShortTy("ushort", Type::UShortTyID);
328 static PrimType TheIntTy ("int" , Type::IntTyID);
329 static PrimType TheUIntTy ("uint" , Type::UIntTyID);
330 static PrimType TheLongTy ("long" , Type::LongTyID);
331 static PrimType TheULongTy ("ulong" , Type::ULongTyID);
332 static PrimType TheFloatTy ("float" , Type::FloatTyID);
333 static PrimType TheDoubleTy("double", Type::DoubleTyID);
334 static PrimType TheLabelTy ("label" , Type::LabelTyID);
336 Type *Type::VoidTy = &TheVoidTy;
337 Type *Type::BoolTy = &TheBoolTy;
338 Type *Type::SByteTy = &TheSByteTy;
339 Type *Type::UByteTy = &TheUByteTy;
340 Type *Type::ShortTy = &TheShortTy;
341 Type *Type::UShortTy = &TheUShortTy;
342 Type *Type::IntTy = &TheIntTy;
343 Type *Type::UIntTy = &TheUIntTy;
344 Type *Type::LongTy = &TheLongTy;
345 Type *Type::ULongTy = &TheULongTy;
346 Type *Type::FloatTy = &TheFloatTy;
347 Type *Type::DoubleTy = &TheDoubleTy;
348 Type *Type::LabelTy = &TheLabelTy;
351 //===----------------------------------------------------------------------===//
352 // Derived Type Constructors
353 //===----------------------------------------------------------------------===//
355 FunctionType::FunctionType(const Type *Result,
356 const std::vector<const Type*> &Params,
357 bool IsVarArgs) : DerivedType(FunctionTyID),
358 isVarArgs(IsVarArgs) {
359 assert((Result->isFirstClassType() || Result == Type::VoidTy ||
360 isa<OpaqueType>(Result)) &&
361 "LLVM functions cannot return aggregates");
362 bool isAbstract = Result->isAbstract();
363 ContainedTys.reserve(Params.size()+1);
364 ContainedTys.push_back(PATypeHandle(Result, this));
366 for (unsigned i = 0; i != Params.size(); ++i) {
367 assert((Params[i]->isFirstClassType() || isa<OpaqueType>(Params[i])) &&
368 "Function arguments must be value types!");
370 ContainedTys.push_back(PATypeHandle(Params[i], this));
371 isAbstract |= Params[i]->isAbstract();
374 // Calculate whether or not this type is abstract
375 setAbstract(isAbstract);
378 StructType::StructType(const std::vector<const Type*> &Types)
379 : CompositeType(StructTyID) {
380 ContainedTys.reserve(Types.size());
381 bool isAbstract = false;
382 for (unsigned i = 0; i < Types.size(); ++i) {
383 assert(Types[i] != Type::VoidTy && "Void type for structure field!!");
384 ContainedTys.push_back(PATypeHandle(Types[i], this));
385 isAbstract |= Types[i]->isAbstract();
388 // Calculate whether or not this type is abstract
389 setAbstract(isAbstract);
392 ArrayType::ArrayType(const Type *ElType, unsigned NumEl)
393 : SequentialType(ArrayTyID, ElType) {
396 // Calculate whether or not this type is abstract
397 setAbstract(ElType->isAbstract());
400 PointerType::PointerType(const Type *E) : SequentialType(PointerTyID, E) {
401 // Calculate whether or not this type is abstract
402 setAbstract(E->isAbstract());
405 OpaqueType::OpaqueType() : DerivedType(OpaqueTyID) {
407 #ifdef DEBUG_MERGE_TYPES
408 std::cerr << "Derived new type: " << *this << "\n";
412 // dropAllTypeUses - When this (abstract) type is resolved to be equal to
413 // another (more concrete) type, we must eliminate all references to other
414 // types, to avoid some circular reference problems.
415 void DerivedType::dropAllTypeUses() {
416 if (!ContainedTys.empty()) {
417 while (ContainedTys.size() > 1)
418 ContainedTys.pop_back();
420 // The type must stay abstract. To do this, we insert a pointer to a type
421 // that will never get resolved, thus will always be abstract.
422 static Type *AlwaysOpaqueTy = OpaqueType::get();
423 static PATypeHolder Holder(AlwaysOpaqueTy);
424 ContainedTys[0] = AlwaysOpaqueTy;
428 // isTypeAbstract - This is a recursive function that walks a type hierarchy
429 // calculating whether or not a type is abstract. Worst case it will have to do
430 // a lot of traversing if you have some whacko opaque types, but in most cases,
431 // it will do some simple stuff when it hits non-abstract types that aren't
434 bool Type::isTypeAbstract() {
435 if (!isAbstract()) // Base case for the recursion
436 return false; // Primitive = leaf type
438 if (isa<OpaqueType>(this)) // Base case for the recursion
439 return true; // This whole type is abstract!
441 // We have to guard against recursion. To do this, we temporarily mark this
442 // type as concrete, so that if we get back to here recursively we will think
443 // it's not abstract, and thus not scan it again.
446 // Scan all of the sub-types. If any of them are abstract, than so is this
448 for (Type::subtype_iterator I = subtype_begin(), E = subtype_end();
450 if (const_cast<Type*>(I->get())->isTypeAbstract()) {
451 setAbstract(true); // Restore the abstract bit.
452 return true; // This type is abstract if subtype is abstract!
455 // Restore the abstract bit.
458 // Nothing looks abstract here...
463 //===----------------------------------------------------------------------===//
464 // Type Structural Equality Testing
465 //===----------------------------------------------------------------------===//
467 // TypesEqual - Two types are considered structurally equal if they have the
468 // same "shape": Every level and element of the types have identical primitive
469 // ID's, and the graphs have the same edges/nodes in them. Nodes do not have to
470 // be pointer equals to be equivalent though. This uses an optimistic algorithm
471 // that assumes that two graphs are the same until proven otherwise.
473 static bool TypesEqual(const Type *Ty, const Type *Ty2,
474 std::map<const Type *, const Type *> &EqTypes) {
475 if (Ty == Ty2) return true;
476 if (Ty->getTypeID() != Ty2->getTypeID()) return false;
477 if (isa<OpaqueType>(Ty))
478 return false; // Two unequal opaque types are never equal
480 std::map<const Type*, const Type*>::iterator It = EqTypes.lower_bound(Ty);
481 if (It != EqTypes.end() && It->first == Ty)
482 return It->second == Ty2; // Looping back on a type, check for equality
484 // Otherwise, add the mapping to the table to make sure we don't get
485 // recursion on the types...
486 EqTypes.insert(It, std::make_pair(Ty, Ty2));
488 // Two really annoying special cases that breaks an otherwise nice simple
489 // algorithm is the fact that arraytypes have sizes that differentiates types,
490 // and that function types can be varargs or not. Consider this now.
492 if (const PointerType *PTy = dyn_cast<PointerType>(Ty)) {
493 return TypesEqual(PTy->getElementType(),
494 cast<PointerType>(Ty2)->getElementType(), EqTypes);
495 } else if (const StructType *STy = dyn_cast<StructType>(Ty)) {
496 const StructType *STy2 = cast<StructType>(Ty2);
497 if (STy->getNumElements() != STy2->getNumElements()) return false;
498 for (unsigned i = 0, e = STy2->getNumElements(); i != e; ++i)
499 if (!TypesEqual(STy->getElementType(i), STy2->getElementType(i), EqTypes))
502 } else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
503 const ArrayType *ATy2 = cast<ArrayType>(Ty2);
504 return ATy->getNumElements() == ATy2->getNumElements() &&
505 TypesEqual(ATy->getElementType(), ATy2->getElementType(), EqTypes);
506 } else if (const FunctionType *FTy = dyn_cast<FunctionType>(Ty)) {
507 const FunctionType *FTy2 = cast<FunctionType>(Ty2);
508 if (FTy->isVarArg() != FTy2->isVarArg() ||
509 FTy->getNumParams() != FTy2->getNumParams() ||
510 !TypesEqual(FTy->getReturnType(), FTy2->getReturnType(), EqTypes))
512 for (unsigned i = 0, e = FTy2->getNumParams(); i != e; ++i)
513 if (!TypesEqual(FTy->getParamType(i), FTy2->getParamType(i), EqTypes))
517 assert(0 && "Unknown derived type!");
522 static bool TypesEqual(const Type *Ty, const Type *Ty2) {
523 std::map<const Type *, const Type *> EqTypes;
524 return TypesEqual(Ty, Ty2, EqTypes);
527 // TypeHasCycleThrough - Return true there is a path from CurTy to TargetTy in
528 // the type graph. We know that Ty is an abstract type, so if we ever reach a
529 // non-abstract type, we know that we don't need to search the subgraph.
530 static bool TypeHasCycleThrough(const Type *TargetTy, const Type *CurTy,
531 std::set<const Type*> &VisitedTypes) {
532 if (TargetTy == CurTy) return true;
533 if (!CurTy->isAbstract()) return false;
535 std::set<const Type*>::iterator VTI = VisitedTypes.lower_bound(CurTy);
536 if (VTI != VisitedTypes.end() && *VTI == CurTy)
538 VisitedTypes.insert(VTI, CurTy);
540 for (Type::subtype_iterator I = CurTy->subtype_begin(),
541 E = CurTy->subtype_end(); I != E; ++I)
542 if (TypeHasCycleThrough(TargetTy, *I, VisitedTypes))
548 /// TypeHasCycleThroughItself - Return true if the specified type has a cycle
550 static bool TypeHasCycleThroughItself(const Type *Ty) {
551 assert(Ty->isAbstract() && "This code assumes that Ty was abstract!");
552 std::set<const Type*> VisitedTypes;
553 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end();
555 if (TypeHasCycleThrough(Ty, *I, VisitedTypes))
561 //===----------------------------------------------------------------------===//
562 // Derived Type Factory Functions
563 //===----------------------------------------------------------------------===//
565 // TypeMap - Make sure that only one instance of a particular type may be
566 // created on any given run of the compiler... note that this involves updating
567 // our map if an abstract type gets refined somehow.
570 template<class ValType, class TypeClass>
572 std::map<ValType, PATypeHolder> Map;
574 /// TypesByHash - Keep track of each type by its structure hash value.
576 std::multimap<unsigned, PATypeHolder> TypesByHash;
578 typedef typename std::map<ValType, PATypeHolder>::iterator iterator;
579 ~TypeMap() { print("ON EXIT"); }
581 inline TypeClass *get(const ValType &V) {
582 iterator I = Map.find(V);
583 return I != Map.end() ? cast<TypeClass>((Type*)I->second.get()) : 0;
586 inline void add(const ValType &V, TypeClass *Ty) {
587 Map.insert(std::make_pair(V, Ty));
589 // If this type has a cycle, remember it.
590 TypesByHash.insert(std::make_pair(ValType::hashTypeStructure(Ty), Ty));
594 void RemoveFromTypesByHash(unsigned Hash, const Type *Ty) {
595 std::multimap<unsigned, PATypeHolder>::iterator I =
596 TypesByHash.lower_bound(Hash);
597 while (I->second != Ty) {
599 assert(I != TypesByHash.end() && I->first == Hash);
601 TypesByHash.erase(I);
604 /// finishRefinement - This method is called after we have updated an existing
605 /// type with its new components. We must now either merge the type away with
606 /// some other type or reinstall it in the map with it's new configuration.
607 /// The specified iterator tells us what the type USED to look like.
608 void finishRefinement(TypeClass *Ty, const DerivedType *OldType,
609 const Type *NewType) {
610 assert((Ty->isAbstract() || !OldType->isAbstract()) &&
611 "Refining a non-abstract type!");
612 #ifdef DEBUG_MERGE_TYPES
613 std::cerr << "refineAbstractTy(" << (void*)OldType << "[" << *OldType
614 << "], " << (void*)NewType << " [" << *NewType << "])\n";
617 // Make a temporary type holder for the type so that it doesn't disappear on
618 // us when we erase the entry from the map.
619 PATypeHolder TyHolder = Ty;
621 // The old record is now out-of-date, because one of the children has been
622 // updated. Remove the obsolete entry from the map.
623 Map.erase(ValType::get(Ty));
625 // Remember the structural hash for the type before we start hacking on it,
626 // in case we need it later. Also, check to see if the type HAD a cycle
627 // through it, if so, we know it will when we hack on it.
628 unsigned OldTypeHash = ValType::hashTypeStructure(Ty);
630 // Find the type element we are refining... and change it now!
631 for (unsigned i = 0, e = Ty->ContainedTys.size(); i != e; ++i)
632 if (Ty->ContainedTys[i] == OldType) {
633 Ty->ContainedTys[i].removeUserFromConcrete();
634 Ty->ContainedTys[i] = NewType;
637 unsigned TypeHash = ValType::hashTypeStructure(Ty);
639 // If there are no cycles going through this node, we can do a simple,
640 // efficient lookup in the map, instead of an inefficient nasty linear
642 bool TypeHasCycle = Ty->isAbstract() && TypeHasCycleThroughItself(Ty);
644 iterator I = Map.find(ValType::get(Ty));
645 if (I != Map.end()) {
646 // We already have this type in the table. Get rid of the newly refined
648 assert(Ty->isAbstract() && "Replacing a non-abstract type?");
649 TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get());
651 // Refined to a different type altogether?
652 RemoveFromTypesByHash(TypeHash, Ty);
653 Ty->refineAbstractTypeTo(NewTy);
658 // Now we check to see if there is an existing entry in the table which is
659 // structurally identical to the newly refined type. If so, this type
660 // gets refined to the pre-existing type.
662 std::multimap<unsigned, PATypeHolder>::iterator I,E, Entry;
663 tie(I, E) = TypesByHash.equal_range(TypeHash);
665 for (; I != E; ++I) {
666 if (I->second != Ty) {
667 if (TypesEqual(Ty, I->second)) {
668 assert(Ty->isAbstract() && "Replacing a non-abstract type?");
669 TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get());
672 // Find the location of Ty in the TypesByHash structure.
673 while (I->second != Ty) {
675 assert(I != E && "Structure doesn't contain type??");
680 TypesByHash.erase(Entry);
681 Ty->refineAbstractTypeTo(NewTy);
685 // Remember the position of
691 // If we succeeded, we need to insert the type into the cycletypes table.
692 // There are several cases here, depending on whether the original type
693 // had the same hash code and was itself cyclic.
694 if (TypeHash != OldTypeHash) {
695 RemoveFromTypesByHash(OldTypeHash, Ty);
696 TypesByHash.insert(std::make_pair(TypeHash, Ty));
699 // If there is no existing type of the same structure, we reinsert an
700 // updated record into the map.
701 Map.insert(std::make_pair(ValType::get(Ty), Ty));
703 // If the type is currently thought to be abstract, rescan all of our
704 // subtypes to see if the type has just become concrete!
705 if (Ty->isAbstract()) {
706 Ty->setAbstract(Ty->isTypeAbstract());
708 // If the type just became concrete, notify all users!
709 if (!Ty->isAbstract())
710 Ty->notifyUsesThatTypeBecameConcrete();
714 void print(const char *Arg) const {
715 #ifdef DEBUG_MERGE_TYPES
716 std::cerr << "TypeMap<>::" << Arg << " table contents:\n";
718 for (typename std::map<ValType, PATypeHolder>::const_iterator I
719 = Map.begin(), E = Map.end(); I != E; ++I)
720 std::cerr << " " << (++i) << ". " << (void*)I->second.get() << " "
721 << *I->second.get() << "\n";
725 void dump() const { print("dump output"); }
730 //===----------------------------------------------------------------------===//
731 // Function Type Factory and Value Class...
734 // FunctionValType - Define a class to hold the key that goes into the TypeMap
737 class FunctionValType {
739 std::vector<const Type*> ArgTypes;
742 FunctionValType(const Type *ret, const std::vector<const Type*> &args,
743 bool IVA) : RetTy(ret), isVarArg(IVA) {
744 for (unsigned i = 0; i < args.size(); ++i)
745 ArgTypes.push_back(args[i]);
748 static FunctionValType get(const FunctionType *FT);
750 static unsigned hashTypeStructure(const FunctionType *FT) {
751 return FT->getNumParams()*2+FT->isVarArg();
754 // Subclass should override this... to update self as usual
755 void doRefinement(const DerivedType *OldType, const Type *NewType) {
756 if (RetTy == OldType) RetTy = NewType;
757 for (unsigned i = 0, e = ArgTypes.size(); i != e; ++i)
758 if (ArgTypes[i] == OldType) ArgTypes[i] = NewType;
761 inline bool operator<(const FunctionValType &MTV) const {
762 if (RetTy < MTV.RetTy) return true;
763 if (RetTy > MTV.RetTy) return false;
765 if (ArgTypes < MTV.ArgTypes) return true;
766 return ArgTypes == MTV.ArgTypes && isVarArg < MTV.isVarArg;
771 // Define the actual map itself now...
772 static TypeMap<FunctionValType, FunctionType> FunctionTypes;
774 FunctionValType FunctionValType::get(const FunctionType *FT) {
775 // Build up a FunctionValType
776 std::vector<const Type *> ParamTypes;
777 ParamTypes.reserve(FT->getNumParams());
778 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
779 ParamTypes.push_back(FT->getParamType(i));
780 return FunctionValType(FT->getReturnType(), ParamTypes, FT->isVarArg());
784 // FunctionType::get - The factory function for the FunctionType class...
785 FunctionType *FunctionType::get(const Type *ReturnType,
786 const std::vector<const Type*> &Params,
788 FunctionValType VT(ReturnType, Params, isVarArg);
789 FunctionType *MT = FunctionTypes.get(VT);
792 FunctionTypes.add(VT, MT = new FunctionType(ReturnType, Params, isVarArg));
794 #ifdef DEBUG_MERGE_TYPES
795 std::cerr << "Derived new type: " << MT << "\n";
800 //===----------------------------------------------------------------------===//
801 // Array Type Factory...
808 ArrayValType(const Type *val, int sz) : ValTy(val), Size(sz) {}
810 static ArrayValType get(const ArrayType *AT) {
811 return ArrayValType(AT->getElementType(), AT->getNumElements());
814 static unsigned hashTypeStructure(const ArrayType *AT) {
815 return AT->getNumElements();
818 // Subclass should override this... to update self as usual
819 void doRefinement(const DerivedType *OldType, const Type *NewType) {
820 assert(ValTy == OldType);
824 inline bool operator<(const ArrayValType &MTV) const {
825 if (Size < MTV.Size) return true;
826 return Size == MTV.Size && ValTy < MTV.ValTy;
830 static TypeMap<ArrayValType, ArrayType> ArrayTypes;
833 ArrayType *ArrayType::get(const Type *ElementType, unsigned NumElements) {
834 assert(ElementType && "Can't get array of null types!");
836 ArrayValType AVT(ElementType, NumElements);
837 ArrayType *AT = ArrayTypes.get(AVT);
838 if (AT) return AT; // Found a match, return it!
840 // Value not found. Derive a new type!
841 ArrayTypes.add(AVT, AT = new ArrayType(ElementType, NumElements));
843 #ifdef DEBUG_MERGE_TYPES
844 std::cerr << "Derived new type: " << *AT << "\n";
849 //===----------------------------------------------------------------------===//
850 // Struct Type Factory...
854 // StructValType - Define a class to hold the key that goes into the TypeMap
856 class StructValType {
857 std::vector<const Type*> ElTypes;
859 StructValType(const std::vector<const Type*> &args) : ElTypes(args) {}
861 static StructValType get(const StructType *ST) {
862 std::vector<const Type *> ElTypes;
863 ElTypes.reserve(ST->getNumElements());
864 for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i)
865 ElTypes.push_back(ST->getElementType(i));
867 return StructValType(ElTypes);
870 static unsigned hashTypeStructure(const StructType *ST) {
871 return ST->getNumElements();
874 // Subclass should override this... to update self as usual
875 void doRefinement(const DerivedType *OldType, const Type *NewType) {
876 for (unsigned i = 0; i < ElTypes.size(); ++i)
877 if (ElTypes[i] == OldType) ElTypes[i] = NewType;
880 inline bool operator<(const StructValType &STV) const {
881 return ElTypes < STV.ElTypes;
886 static TypeMap<StructValType, StructType> StructTypes;
888 StructType *StructType::get(const std::vector<const Type*> &ETypes) {
889 StructValType STV(ETypes);
890 StructType *ST = StructTypes.get(STV);
893 // Value not found. Derive a new type!
894 StructTypes.add(STV, ST = new StructType(ETypes));
896 #ifdef DEBUG_MERGE_TYPES
897 std::cerr << "Derived new type: " << *ST << "\n";
904 //===----------------------------------------------------------------------===//
905 // Pointer Type Factory...
908 // PointerValType - Define a class to hold the key that goes into the TypeMap
911 class PointerValType {
914 PointerValType(const Type *val) : ValTy(val) {}
916 static PointerValType get(const PointerType *PT) {
917 return PointerValType(PT->getElementType());
920 static unsigned hashTypeStructure(const PointerType *PT) {
924 // Subclass should override this... to update self as usual
925 void doRefinement(const DerivedType *OldType, const Type *NewType) {
926 assert(ValTy == OldType);
930 bool operator<(const PointerValType &MTV) const {
931 return ValTy < MTV.ValTy;
936 static TypeMap<PointerValType, PointerType> PointerTypes;
938 PointerType *PointerType::get(const Type *ValueType) {
939 assert(ValueType && "Can't get a pointer to <null> type!");
940 PointerValType PVT(ValueType);
942 PointerType *PT = PointerTypes.get(PVT);
945 // Value not found. Derive a new type!
946 PointerTypes.add(PVT, PT = new PointerType(ValueType));
948 #ifdef DEBUG_MERGE_TYPES
949 std::cerr << "Derived new type: " << *PT << "\n";
955 //===----------------------------------------------------------------------===//
956 // Derived Type Refinement Functions
957 //===----------------------------------------------------------------------===//
959 // removeAbstractTypeUser - Notify an abstract type that a user of the class
960 // no longer has a handle to the type. This function is called primarily by
961 // the PATypeHandle class. When there are no users of the abstract type, it
962 // is annihilated, because there is no way to get a reference to it ever again.
964 void DerivedType::removeAbstractTypeUser(AbstractTypeUser *U) const {
965 // Search from back to front because we will notify users from back to
966 // front. Also, it is likely that there will be a stack like behavior to
967 // users that register and unregister users.
970 for (i = AbstractTypeUsers.size(); AbstractTypeUsers[i-1] != U; --i)
971 assert(i != 0 && "AbstractTypeUser not in user list!");
973 --i; // Convert to be in range 0 <= i < size()
974 assert(i < AbstractTypeUsers.size() && "Index out of range!"); // Wraparound?
976 AbstractTypeUsers.erase(AbstractTypeUsers.begin()+i);
978 #ifdef DEBUG_MERGE_TYPES
979 std::cerr << " remAbstractTypeUser[" << (void*)this << ", "
980 << *this << "][" << i << "] User = " << U << "\n";
983 if (AbstractTypeUsers.empty() && getRefCount() == 0 && isAbstract()) {
984 #ifdef DEBUG_MERGE_TYPES
985 std::cerr << "DELETEing unused abstract type: <" << *this
986 << ">[" << (void*)this << "]" << "\n";
988 delete this; // No users of this abstract type!
993 // refineAbstractTypeTo - This function is used to when it is discovered that
994 // the 'this' abstract type is actually equivalent to the NewType specified.
995 // This causes all users of 'this' to switch to reference the more concrete type
996 // NewType and for 'this' to be deleted.
998 void DerivedType::refineAbstractTypeTo(const Type *NewType) {
999 assert(isAbstract() && "refineAbstractTypeTo: Current type is not abstract!");
1000 assert(this != NewType && "Can't refine to myself!");
1001 assert(ForwardType == 0 && "This type has already been refined!");
1003 // The descriptions may be out of date. Conservatively clear them all!
1004 AbstractTypeDescriptions.clear();
1006 #ifdef DEBUG_MERGE_TYPES
1007 std::cerr << "REFINING abstract type [" << (void*)this << " "
1008 << *this << "] to [" << (void*)NewType << " "
1009 << *NewType << "]!\n";
1012 // Make sure to put the type to be refined to into a holder so that if IT gets
1013 // refined, that we will not continue using a dead reference...
1015 PATypeHolder NewTy(NewType);
1017 // Any PATypeHolders referring to this type will now automatically forward to
1018 // the type we are resolved to.
1019 ForwardType = NewType;
1020 if (NewType->isAbstract())
1021 cast<DerivedType>(NewType)->addRef();
1023 // Add a self use of the current type so that we don't delete ourself until
1024 // after the function exits.
1026 PATypeHolder CurrentTy(this);
1028 // To make the situation simpler, we ask the subclass to remove this type from
1029 // the type map, and to replace any type uses with uses of non-abstract types.
1030 // This dramatically limits the amount of recursive type trouble we can find
1034 // Iterate over all of the uses of this type, invoking callback. Each user
1035 // should remove itself from our use list automatically. We have to check to
1036 // make sure that NewTy doesn't _become_ 'this'. If it does, resolving types
1037 // will not cause users to drop off of the use list. If we resolve to ourself
1040 while (!AbstractTypeUsers.empty() && NewTy != this) {
1041 AbstractTypeUser *User = AbstractTypeUsers.back();
1043 unsigned OldSize = AbstractTypeUsers.size();
1044 #ifdef DEBUG_MERGE_TYPES
1045 std::cerr << " REFINING user " << OldSize-1 << "[" << (void*)User
1046 << "] of abstract type [" << (void*)this << " "
1047 << *this << "] to [" << (void*)NewTy.get() << " "
1048 << *NewTy << "]!\n";
1050 User->refineAbstractType(this, NewTy);
1052 assert(AbstractTypeUsers.size() != OldSize &&
1053 "AbsTyUser did not remove self from user list!");
1056 // If we were successful removing all users from the type, 'this' will be
1057 // deleted when the last PATypeHolder is destroyed or updated from this type.
1058 // This may occur on exit of this function, as the CurrentTy object is
1062 // notifyUsesThatTypeBecameConcrete - Notify AbstractTypeUsers of this type that
1063 // the current type has transitioned from being abstract to being concrete.
1065 void DerivedType::notifyUsesThatTypeBecameConcrete() {
1066 #ifdef DEBUG_MERGE_TYPES
1067 std::cerr << "typeIsREFINED type: " << (void*)this << " " << *this << "\n";
1070 unsigned OldSize = AbstractTypeUsers.size();
1071 while (!AbstractTypeUsers.empty()) {
1072 AbstractTypeUser *ATU = AbstractTypeUsers.back();
1073 ATU->typeBecameConcrete(this);
1075 assert(AbstractTypeUsers.size() < OldSize-- &&
1076 "AbstractTypeUser did not remove itself from the use list!");
1083 // refineAbstractType - Called when a contained type is found to be more
1084 // concrete - this could potentially change us from an abstract type to a
1087 void FunctionType::refineAbstractType(const DerivedType *OldType,
1088 const Type *NewType) {
1089 FunctionTypes.finishRefinement(this, OldType, NewType);
1092 void FunctionType::typeBecameConcrete(const DerivedType *AbsTy) {
1093 refineAbstractType(AbsTy, AbsTy);
1097 // refineAbstractType - Called when a contained type is found to be more
1098 // concrete - this could potentially change us from an abstract type to a
1101 void ArrayType::refineAbstractType(const DerivedType *OldType,
1102 const Type *NewType) {
1103 ArrayTypes.finishRefinement(this, OldType, NewType);
1106 void ArrayType::typeBecameConcrete(const DerivedType *AbsTy) {
1107 refineAbstractType(AbsTy, AbsTy);
1111 // refineAbstractType - Called when a contained type is found to be more
1112 // concrete - this could potentially change us from an abstract type to a
1115 void StructType::refineAbstractType(const DerivedType *OldType,
1116 const Type *NewType) {
1117 StructTypes.finishRefinement(this, OldType, NewType);
1120 void StructType::typeBecameConcrete(const DerivedType *AbsTy) {
1121 refineAbstractType(AbsTy, AbsTy);
1124 // refineAbstractType - Called when a contained type is found to be more
1125 // concrete - this could potentially change us from an abstract type to a
1128 void PointerType::refineAbstractType(const DerivedType *OldType,
1129 const Type *NewType) {
1130 PointerTypes.finishRefinement(this, OldType, NewType);
1133 void PointerType::typeBecameConcrete(const DerivedType *AbsTy) {
1134 refineAbstractType(AbsTy, AbsTy);
1137 bool SequentialType::indexValid(const Value *V) const {
1138 const Type *Ty = V->getType();
1139 switch (Ty->getTypeID()) {
1141 case Type::UIntTyID:
1142 case Type::LongTyID:
1143 case Type::ULongTyID:
1151 std::ostream &operator<<(std::ostream &OS, const Type *T) {
1153 OS << "<null> value!\n";
1159 std::ostream &operator<<(std::ostream &OS, const Type &T) {