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/DerivedTypes.h"
15 #include "llvm/SymbolTable.h"
16 #include "llvm/Constants.h"
17 #include "Support/DepthFirstIterator.h"
18 #include "Support/StringExtras.h"
19 #include "Support/STLExtras.h"
23 // DEBUG_MERGE_TYPES - Enable this #define to see how and when derived types are
24 // created and later destroyed, all in an effort to make sure that there is only
25 // a single canonical version of a type.
27 //#define DEBUG_MERGE_TYPES 1
29 AbstractTypeUser::~AbstractTypeUser() {}
31 //===----------------------------------------------------------------------===//
32 // Type Class Implementation
33 //===----------------------------------------------------------------------===//
35 static unsigned CurUID = 0;
36 static std::vector<const Type *> UIDMappings;
38 // Concrete/Abstract TypeDescriptions - We lazily calculate type descriptions
39 // for types as they are needed. Because resolution of types must invalidate
40 // all of the abstract type descriptions, we keep them in a seperate map to make
42 static std::map<const Type*, std::string> ConcreteTypeDescriptions;
43 static std::map<const Type*, std::string> AbstractTypeDescriptions;
45 Type::Type(const std::string &name, PrimitiveID id)
46 : Value(Type::TypeTy, Value::TypeVal), RefCount(0), ForwardType(0) {
48 ConcreteTypeDescriptions[this] = name;
51 UID = CurUID++; // Assign types UID's as they are created
52 UIDMappings.push_back(this);
55 void Type::setName(const std::string &Name, SymbolTable *ST) {
56 assert(ST && "Type::setName - Must provide symbol table argument!");
58 if (Name.size()) ST->insert(Name, this);
62 const Type *Type::getUniqueIDType(unsigned UID) {
63 assert(UID < UIDMappings.size() &&
64 "Type::getPrimitiveType: UID out of range!");
65 return UIDMappings[UID];
68 const Type *Type::getPrimitiveType(PrimitiveID IDNumber) {
70 case VoidTyID : return VoidTy;
71 case BoolTyID : return BoolTy;
72 case UByteTyID : return UByteTy;
73 case SByteTyID : return SByteTy;
74 case UShortTyID: return UShortTy;
75 case ShortTyID : return ShortTy;
76 case UIntTyID : return UIntTy;
77 case IntTyID : return IntTy;
78 case ULongTyID : return ULongTy;
79 case LongTyID : return LongTy;
80 case FloatTyID : return FloatTy;
81 case DoubleTyID: return DoubleTy;
82 case TypeTyID : return TypeTy;
83 case LabelTyID : return LabelTy;
89 // isLosslesslyConvertibleTo - Return true if this type can be converted to
90 // 'Ty' without any reinterpretation of bits. For example, uint to int.
92 bool Type::isLosslesslyConvertibleTo(const Type *Ty) const {
93 if (this == Ty) return true;
94 if ((!isPrimitiveType() && !isa<PointerType>(this)) ||
95 (!isa<PointerType>(Ty) && !Ty->isPrimitiveType())) return false;
97 if (getPrimitiveID() == Ty->getPrimitiveID())
98 return true; // Handles identity cast, and cast of differing pointer types
100 // Now we know that they are two differing primitive or pointer types
101 switch (getPrimitiveID()) {
102 case Type::UByteTyID: return Ty == Type::SByteTy;
103 case Type::SByteTyID: return Ty == Type::UByteTy;
104 case Type::UShortTyID: return Ty == Type::ShortTy;
105 case Type::ShortTyID: return Ty == Type::UShortTy;
106 case Type::UIntTyID: return Ty == Type::IntTy;
107 case Type::IntTyID: return Ty == Type::UIntTy;
108 case Type::ULongTyID: return Ty == Type::LongTy;
109 case Type::LongTyID: return Ty == Type::ULongTy;
110 case Type::PointerTyID: return isa<PointerType>(Ty);
112 return false; // Other types have no identity values
116 // getPrimitiveSize - Return the basic size of this type if it is a primitive
117 // type. These are fixed by LLVM and are not target dependent. This will
118 // return zero if the type does not have a size or is not a primitive type.
120 unsigned Type::getPrimitiveSize() const {
121 switch (getPrimitiveID()) {
122 #define HANDLE_PRIM_TYPE(TY,SIZE) case TY##TyID: return SIZE;
123 #include "llvm/Type.def"
129 /// getForwardedTypeInternal - This method is used to implement the union-find
130 /// algorithm for when a type is being forwarded to another type.
131 const Type *Type::getForwardedTypeInternal() const {
132 assert(ForwardType && "This type is not being forwarded to another type!");
134 // Check to see if the forwarded type has been forwarded on. If so, collapse
135 // the forwarding links.
136 const Type *RealForwardedType = ForwardType->getForwardedType();
137 if (!RealForwardedType)
138 return ForwardType; // No it's not forwarded again
140 // Yes, it is forwarded again. First thing, add the reference to the new
142 if (RealForwardedType->isAbstract())
143 cast<DerivedType>(RealForwardedType)->addRef();
145 // Now drop the old reference. This could cause ForwardType to get deleted.
146 cast<DerivedType>(ForwardType)->dropRef();
148 // Return the updated type.
149 ForwardType = RealForwardedType;
153 // getTypeDescription - This is a recursive function that walks a type hierarchy
154 // calculating the description for a type.
156 static std::string getTypeDescription(const Type *Ty,
157 std::vector<const Type *> &TypeStack) {
158 if (isa<OpaqueType>(Ty)) { // Base case for the recursion
159 std::map<const Type*, std::string>::iterator I =
160 AbstractTypeDescriptions.lower_bound(Ty);
161 if (I != AbstractTypeDescriptions.end() && I->first == Ty)
163 std::string Desc = "opaque"+utostr(Ty->getUniqueID());
164 AbstractTypeDescriptions.insert(std::make_pair(Ty, Desc));
168 if (!Ty->isAbstract()) { // Base case for the recursion
169 std::map<const Type*, std::string>::iterator I =
170 ConcreteTypeDescriptions.find(Ty);
171 if (I != ConcreteTypeDescriptions.end()) return I->second;
174 // Check to see if the Type is already on the stack...
175 unsigned Slot = 0, CurSize = TypeStack.size();
176 while (Slot < CurSize && TypeStack[Slot] != Ty) ++Slot; // Scan for type
178 // This is another base case for the recursion. In this case, we know
179 // that we have looped back to a type that we have previously visited.
180 // Generate the appropriate upreference to handle this.
183 return "\\" + utostr(CurSize-Slot); // Here's the upreference
185 // Recursive case: derived types...
187 TypeStack.push_back(Ty); // Add us to the stack..
189 switch (Ty->getPrimitiveID()) {
190 case Type::FunctionTyID: {
191 const FunctionType *FTy = cast<FunctionType>(Ty);
192 Result = getTypeDescription(FTy->getReturnType(), TypeStack) + " (";
193 for (FunctionType::param_iterator I = FTy->param_begin(),
194 E = FTy->param_end(); I != E; ++I) {
195 if (I != FTy->param_begin())
197 Result += getTypeDescription(*I, TypeStack);
199 if (FTy->isVarArg()) {
200 if (FTy->getNumParams()) Result += ", ";
206 case Type::StructTyID: {
207 const StructType *STy = cast<StructType>(Ty);
209 for (StructType::element_iterator I = STy->element_begin(),
210 E = STy->element_end(); I != E; ++I) {
211 if (I != STy->element_begin())
213 Result += getTypeDescription(*I, TypeStack);
218 case Type::PointerTyID: {
219 const PointerType *PTy = cast<PointerType>(Ty);
220 Result = getTypeDescription(PTy->getElementType(), TypeStack) + " *";
223 case Type::ArrayTyID: {
224 const ArrayType *ATy = cast<ArrayType>(Ty);
225 unsigned NumElements = ATy->getNumElements();
227 Result += utostr(NumElements) + " x ";
228 Result += getTypeDescription(ATy->getElementType(), TypeStack) + "]";
233 assert(0 && "Unhandled type in getTypeDescription!");
236 TypeStack.pop_back(); // Remove self from stack...
243 static const std::string &getOrCreateDesc(std::map<const Type*,std::string>&Map,
245 std::map<const Type*, std::string>::iterator I = Map.find(Ty);
246 if (I != Map.end()) return I->second;
248 std::vector<const Type *> TypeStack;
249 return Map[Ty] = getTypeDescription(Ty, TypeStack);
253 const std::string &Type::getDescription() const {
255 return getOrCreateDesc(AbstractTypeDescriptions, this);
257 return getOrCreateDesc(ConcreteTypeDescriptions, this);
261 bool StructType::indexValid(const Value *V) const {
262 // Structure indexes require unsigned integer constants.
263 if (const ConstantUInt *CU = dyn_cast<ConstantUInt>(V))
264 return CU->getValue() < ContainedTys.size();
268 // getTypeAtIndex - Given an index value into the type, return the type of the
269 // element. For a structure type, this must be a constant value...
271 const Type *StructType::getTypeAtIndex(const Value *V) const {
272 assert(isa<Constant>(V) && "Structure index must be a constant!!");
273 unsigned Idx = cast<ConstantUInt>(V)->getValue();
274 assert(Idx < ContainedTys.size() && "Structure index out of range!");
275 assert(indexValid(V) && "Invalid structure index!"); // Duplicate check
276 return ContainedTys[Idx];
280 //===----------------------------------------------------------------------===//
282 //===----------------------------------------------------------------------===//
284 // These classes are used to implement specialized behavior for each different
287 struct SignedIntType : public Type {
288 SignedIntType(const std::string &Name, PrimitiveID id) : Type(Name, id) {}
290 // isSigned - Return whether a numeric type is signed.
291 virtual bool isSigned() const { return 1; }
293 // isInteger - Equivalent to isSigned() || isUnsigned, but with only a single
294 // virtual function invocation.
296 virtual bool isInteger() const { return 1; }
299 struct UnsignedIntType : public Type {
300 UnsignedIntType(const std::string &N, PrimitiveID id) : Type(N, id) {}
302 // isUnsigned - Return whether a numeric type is signed.
303 virtual bool isUnsigned() const { return 1; }
305 // isInteger - Equivalent to isSigned() || isUnsigned, but with only a single
306 // virtual function invocation.
308 virtual bool isInteger() const { return 1; }
311 struct OtherType : public Type {
312 OtherType(const std::string &N, PrimitiveID id) : Type(N, id) {}
315 static struct TypeType : public Type {
316 TypeType() : Type("type", TypeTyID) {}
317 } TheTypeTy; // Implement the type that is global.
320 //===----------------------------------------------------------------------===//
321 // Static 'Type' data
322 //===----------------------------------------------------------------------===//
324 static OtherType TheVoidTy ("void" , Type::VoidTyID);
325 static OtherType TheBoolTy ("bool" , Type::BoolTyID);
326 static SignedIntType TheSByteTy ("sbyte" , Type::SByteTyID);
327 static UnsignedIntType TheUByteTy ("ubyte" , Type::UByteTyID);
328 static SignedIntType TheShortTy ("short" , Type::ShortTyID);
329 static UnsignedIntType TheUShortTy("ushort", Type::UShortTyID);
330 static SignedIntType TheIntTy ("int" , Type::IntTyID);
331 static UnsignedIntType TheUIntTy ("uint" , Type::UIntTyID);
332 static SignedIntType TheLongTy ("long" , Type::LongTyID);
333 static UnsignedIntType TheULongTy ("ulong" , Type::ULongTyID);
334 static OtherType TheFloatTy ("float" , Type::FloatTyID);
335 static OtherType TheDoubleTy("double", Type::DoubleTyID);
336 static OtherType TheLabelTy ("label" , Type::LabelTyID);
338 Type *Type::VoidTy = &TheVoidTy;
339 Type *Type::BoolTy = &TheBoolTy;
340 Type *Type::SByteTy = &TheSByteTy;
341 Type *Type::UByteTy = &TheUByteTy;
342 Type *Type::ShortTy = &TheShortTy;
343 Type *Type::UShortTy = &TheUShortTy;
344 Type *Type::IntTy = &TheIntTy;
345 Type *Type::UIntTy = &TheUIntTy;
346 Type *Type::LongTy = &TheLongTy;
347 Type *Type::ULongTy = &TheULongTy;
348 Type *Type::FloatTy = &TheFloatTy;
349 Type *Type::DoubleTy = &TheDoubleTy;
350 Type *Type::TypeTy = &TheTypeTy;
351 Type *Type::LabelTy = &TheLabelTy;
354 //===----------------------------------------------------------------------===//
355 // Derived Type Constructors
356 //===----------------------------------------------------------------------===//
358 FunctionType::FunctionType(const Type *Result,
359 const std::vector<const Type*> &Params,
360 bool IsVarArgs) : DerivedType(FunctionTyID),
361 isVarArgs(IsVarArgs) {
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 ContainedTys.push_back(PATypeHandle(Params[i], this));
368 isAbstract |= Params[i]->isAbstract();
371 // Calculate whether or not this type is abstract
372 setAbstract(isAbstract);
375 StructType::StructType(const std::vector<const Type*> &Types)
376 : CompositeType(StructTyID) {
377 ContainedTys.reserve(Types.size());
378 bool isAbstract = false;
379 for (unsigned i = 0; i < Types.size(); ++i) {
380 assert(Types[i] != Type::VoidTy && "Void type in method prototype!!");
381 ContainedTys.push_back(PATypeHandle(Types[i], this));
382 isAbstract |= Types[i]->isAbstract();
385 // Calculate whether or not this type is abstract
386 setAbstract(isAbstract);
389 ArrayType::ArrayType(const Type *ElType, unsigned NumEl)
390 : SequentialType(ArrayTyID, ElType) {
393 // Calculate whether or not this type is abstract
394 setAbstract(ElType->isAbstract());
397 PointerType::PointerType(const Type *E) : SequentialType(PointerTyID, E) {
398 // Calculate whether or not this type is abstract
399 setAbstract(E->isAbstract());
402 OpaqueType::OpaqueType() : DerivedType(OpaqueTyID) {
404 #ifdef DEBUG_MERGE_TYPES
405 std::cerr << "Derived new type: " << *this << "\n";
409 // dropAllTypeUses - When this (abstract) type is resolved to be equal to
410 // another (more concrete) type, we must eliminate all references to other
411 // types, to avoid some circular reference problems.
412 void DerivedType::dropAllTypeUses() {
413 if (!ContainedTys.empty()) {
414 while (ContainedTys.size() > 1)
415 ContainedTys.pop_back();
417 // The type must stay abstract. To do this, we insert a pointer to a type
418 // that will never get resolved, thus will always be abstract.
419 static Type *AlwaysOpaqueTy = OpaqueType::get();
420 static PATypeHolder Holder(AlwaysOpaqueTy);
421 ContainedTys[0] = AlwaysOpaqueTy;
425 // isTypeAbstract - This is a recursive function that walks a type hierarchy
426 // calculating whether or not a type is abstract. Worst case it will have to do
427 // a lot of traversing if you have some whacko opaque types, but in most cases,
428 // it will do some simple stuff when it hits non-abstract types that aren't
431 bool Type::isTypeAbstract() {
432 if (!isAbstract()) // Base case for the recursion
433 return false; // Primitive = leaf type
435 if (isa<OpaqueType>(this)) // Base case for the recursion
436 return true; // This whole type is abstract!
438 // We have to guard against recursion. To do this, we temporarily mark this
439 // type as concrete, so that if we get back to here recursively we will think
440 // it's not abstract, and thus not scan it again.
443 // Scan all of the sub-types. If any of them are abstract, than so is this
445 for (Type::subtype_iterator I = subtype_begin(), E = subtype_end();
447 if (const_cast<Type*>(I->get())->isTypeAbstract()) {
448 setAbstract(true); // Restore the abstract bit.
449 return true; // This type is abstract if subtype is abstract!
452 // Restore the abstract bit.
455 // Nothing looks abstract here...
460 //===----------------------------------------------------------------------===//
461 // Type Structural Equality Testing
462 //===----------------------------------------------------------------------===//
464 // TypesEqual - Two types are considered structurally equal if they have the
465 // same "shape": Every level and element of the types have identical primitive
466 // ID's, and the graphs have the same edges/nodes in them. Nodes do not have to
467 // be pointer equals to be equivalent though. This uses an optimistic algorithm
468 // that assumes that two graphs are the same until proven otherwise.
470 static bool TypesEqual(const Type *Ty, const Type *Ty2,
471 std::map<const Type *, const Type *> &EqTypes) {
472 if (Ty == Ty2) return true;
473 if (Ty->getPrimitiveID() != Ty2->getPrimitiveID()) return false;
474 if (isa<OpaqueType>(Ty))
475 return false; // Two unequal opaque types are never equal
477 std::map<const Type*, const Type*>::iterator It = EqTypes.lower_bound(Ty);
478 if (It != EqTypes.end() && It->first == Ty)
479 return It->second == Ty2; // Looping back on a type, check for equality
481 // Otherwise, add the mapping to the table to make sure we don't get
482 // recursion on the types...
483 EqTypes.insert(It, std::make_pair(Ty, Ty2));
485 // Two really annoying special cases that breaks an otherwise nice simple
486 // algorithm is the fact that arraytypes have sizes that differentiates types,
487 // and that function types can be varargs or not. Consider this now.
489 if (const PointerType *PTy = dyn_cast<PointerType>(Ty)) {
490 return TypesEqual(PTy->getElementType(),
491 cast<PointerType>(Ty2)->getElementType(), EqTypes);
492 } else if (const StructType *STy = dyn_cast<StructType>(Ty)) {
493 const StructType *STy2 = cast<StructType>(Ty2);
494 if (STy->getNumElements() != STy2->getNumElements()) return false;
495 for (unsigned i = 0, e = STy2->getNumElements(); i != e; ++i)
496 if (!TypesEqual(STy->getElementType(i), STy2->getElementType(i), EqTypes))
499 } else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
500 const ArrayType *ATy2 = cast<ArrayType>(Ty2);
501 return ATy->getNumElements() == ATy2->getNumElements() &&
502 TypesEqual(ATy->getElementType(), ATy2->getElementType(), EqTypes);
503 } else if (const FunctionType *FTy = dyn_cast<FunctionType>(Ty)) {
504 const FunctionType *FTy2 = cast<FunctionType>(Ty2);
505 if (FTy->isVarArg() != FTy2->isVarArg() ||
506 FTy->getNumParams() != FTy2->getNumParams() ||
507 !TypesEqual(FTy->getReturnType(), FTy2->getReturnType(), EqTypes))
509 for (unsigned i = 0, e = FTy2->getNumParams(); i != e; ++i)
510 if (!TypesEqual(FTy->getParamType(i), FTy2->getParamType(i), EqTypes))
514 assert(0 && "Unknown derived type!");
519 static bool TypesEqual(const Type *Ty, const Type *Ty2) {
520 std::map<const Type *, const Type *> EqTypes;
521 return TypesEqual(Ty, Ty2, EqTypes);
524 // TypeHasCycleThrough - Return true there is a path from CurTy to TargetTy in
525 // the type graph. We know that Ty is an abstract type, so if we ever reach a
526 // non-abstract type, we know that we don't need to search the subgraph.
527 static bool TypeHasCycleThrough(const Type *TargetTy, const Type *CurTy,
528 std::set<const Type*> &VisitedTypes) {
529 if (TargetTy == CurTy) return true;
530 if (!CurTy->isAbstract()) return false;
532 std::set<const Type*>::iterator VTI = VisitedTypes.lower_bound(CurTy);
533 if (VTI != VisitedTypes.end() && *VTI == CurTy)
535 VisitedTypes.insert(VTI, CurTy);
537 for (Type::subtype_iterator I = CurTy->subtype_begin(),
538 E = CurTy->subtype_end(); I != E; ++I)
539 if (TypeHasCycleThrough(TargetTy, *I, VisitedTypes))
545 /// TypeHasCycleThroughItself - Return true if the specified type has a cycle
547 static bool TypeHasCycleThroughItself(const Type *Ty) {
548 assert(Ty->isAbstract() && "This code assumes that Ty was abstract!");
549 std::set<const Type*> VisitedTypes;
550 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end();
552 if (TypeHasCycleThrough(Ty, *I, VisitedTypes))
558 //===----------------------------------------------------------------------===//
559 // Derived Type Factory Functions
560 //===----------------------------------------------------------------------===//
562 // TypeMap - Make sure that only one instance of a particular type may be
563 // created on any given run of the compiler... note that this involves updating
564 // our map if an abstract type gets refined somehow.
567 template<class ValType, class TypeClass>
569 std::map<ValType, PATypeHolder> Map;
571 /// TypesByHash - Keep track of each type by its structure hash value.
573 std::multimap<unsigned, PATypeHolder> TypesByHash;
575 typedef typename std::map<ValType, PATypeHolder>::iterator iterator;
576 ~TypeMap() { print("ON EXIT"); }
578 inline TypeClass *get(const ValType &V) {
579 iterator I = Map.find(V);
580 return I != Map.end() ? cast<TypeClass>((Type*)I->second.get()) : 0;
583 inline void add(const ValType &V, TypeClass *Ty) {
584 Map.insert(std::make_pair(V, Ty));
586 // If this type has a cycle, remember it.
587 TypesByHash.insert(std::make_pair(ValType::hashTypeStructure(Ty), Ty));
591 void RemoveFromTypesByHash(unsigned Hash, const Type *Ty) {
592 std::multimap<unsigned, PATypeHolder>::iterator I =
593 TypesByHash.lower_bound(Hash);
594 while (I->second != Ty) {
596 assert(I != TypesByHash.end() && I->first == Hash);
598 TypesByHash.erase(I);
601 /// finishRefinement - This method is called after we have updated an existing
602 /// type with its new components. We must now either merge the type away with
603 /// some other type or reinstall it in the map with it's new configuration.
604 /// The specified iterator tells us what the type USED to look like.
605 void finishRefinement(TypeClass *Ty, const DerivedType *OldType,
606 const Type *NewType) {
607 assert((Ty->isAbstract() || !OldType->isAbstract()) &&
608 "Refining a non-abstract type!");
609 #ifdef DEBUG_MERGE_TYPES
610 std::cerr << "refineAbstractTy(" << (void*)OldType << "[" << *OldType
611 << "], " << (void*)NewType << " [" << *NewType << "])\n";
614 // Make a temporary type holder for the type so that it doesn't disappear on
615 // us when we erase the entry from the map.
616 PATypeHolder TyHolder = Ty;
618 // The old record is now out-of-date, because one of the children has been
619 // updated. Remove the obsolete entry from the map.
620 Map.erase(ValType::get(Ty));
622 // Remember the structural hash for the type before we start hacking on it,
623 // in case we need it later. Also, check to see if the type HAD a cycle
624 // through it, if so, we know it will when we hack on it.
625 unsigned OldTypeHash = ValType::hashTypeStructure(Ty);
627 // Find the type element we are refining... and change it now!
628 for (unsigned i = 0, e = Ty->ContainedTys.size(); i != e; ++i)
629 if (Ty->ContainedTys[i] == OldType) {
630 Ty->ContainedTys[i].removeUserFromConcrete();
631 Ty->ContainedTys[i] = NewType;
634 unsigned TypeHash = ValType::hashTypeStructure(Ty);
636 // If there are no cycles going through this node, we can do a simple,
637 // efficient lookup in the map, instead of an inefficient nasty linear
639 bool TypeHasCycle = Ty->isAbstract() && TypeHasCycleThroughItself(Ty);
641 iterator I = Map.find(ValType::get(Ty));
642 if (I != Map.end()) {
643 // We already have this type in the table. Get rid of the newly refined
645 assert(Ty->isAbstract() && "Replacing a non-abstract type?");
646 TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get());
648 // Refined to a different type altogether?
649 RemoveFromTypesByHash(TypeHash, Ty);
650 Ty->refineAbstractTypeTo(NewTy);
655 // Now we check to see if there is an existing entry in the table which is
656 // structurally identical to the newly refined type. If so, this type
657 // gets refined to the pre-existing type.
659 std::multimap<unsigned, PATypeHolder>::iterator I,E, Entry;
660 tie(I, E) = TypesByHash.equal_range(TypeHash);
662 for (; I != E; ++I) {
663 if (I->second != Ty) {
664 if (TypesEqual(Ty, I->second)) {
665 assert(Ty->isAbstract() && "Replacing a non-abstract type?");
666 TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get());
669 // Find the location of Ty in the TypesByHash structure.
670 while (I->second != Ty) {
672 assert(I != E && "Structure doesn't contain type??");
677 TypesByHash.erase(Entry);
678 Ty->refineAbstractTypeTo(NewTy);
682 // Remember the position of
688 // If we succeeded, we need to insert the type into the cycletypes table.
689 // There are several cases here, depending on whether the original type
690 // had the same hash code and was itself cyclic.
691 if (TypeHash != OldTypeHash) {
692 RemoveFromTypesByHash(OldTypeHash, Ty);
693 TypesByHash.insert(std::make_pair(TypeHash, Ty));
696 // If there is no existing type of the same structure, we reinsert an
697 // updated record into the map.
698 Map.insert(std::make_pair(ValType::get(Ty), Ty));
700 // If the type is currently thought to be abstract, rescan all of our
701 // subtypes to see if the type has just become concrete!
702 if (Ty->isAbstract()) {
703 Ty->setAbstract(Ty->isTypeAbstract());
705 // If the type just became concrete, notify all users!
706 if (!Ty->isAbstract())
707 Ty->notifyUsesThatTypeBecameConcrete();
711 void print(const char *Arg) const {
712 #ifdef DEBUG_MERGE_TYPES
713 std::cerr << "TypeMap<>::" << Arg << " table contents:\n";
715 for (typename std::map<ValType, PATypeHolder>::const_iterator I
716 = Map.begin(), E = Map.end(); I != E; ++I)
717 std::cerr << " " << (++i) << ". " << (void*)I->second.get() << " "
718 << *I->second.get() << "\n";
722 void dump() const { print("dump output"); }
727 //===----------------------------------------------------------------------===//
728 // Function Type Factory and Value Class...
731 // FunctionValType - Define a class to hold the key that goes into the TypeMap
734 class FunctionValType {
736 std::vector<const Type*> ArgTypes;
739 FunctionValType(const Type *ret, const std::vector<const Type*> &args,
740 bool IVA) : RetTy(ret), isVarArg(IVA) {
741 for (unsigned i = 0; i < args.size(); ++i)
742 ArgTypes.push_back(args[i]);
745 static FunctionValType get(const FunctionType *FT);
747 static unsigned hashTypeStructure(const FunctionType *FT) {
748 return FT->getNumParams()*2+FT->isVarArg();
751 // Subclass should override this... to update self as usual
752 void doRefinement(const DerivedType *OldType, const Type *NewType) {
753 if (RetTy == OldType) RetTy = NewType;
754 for (unsigned i = 0, e = ArgTypes.size(); i != e; ++i)
755 if (ArgTypes[i] == OldType) ArgTypes[i] = NewType;
758 inline bool operator<(const FunctionValType &MTV) const {
759 if (RetTy < MTV.RetTy) return true;
760 if (RetTy > MTV.RetTy) return false;
762 if (ArgTypes < MTV.ArgTypes) return true;
763 return ArgTypes == MTV.ArgTypes && isVarArg < MTV.isVarArg;
768 // Define the actual map itself now...
769 static TypeMap<FunctionValType, FunctionType> FunctionTypes;
771 FunctionValType FunctionValType::get(const FunctionType *FT) {
772 // Build up a FunctionValType
773 std::vector<const Type *> ParamTypes;
774 ParamTypes.reserve(FT->getNumParams());
775 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
776 ParamTypes.push_back(FT->getParamType(i));
777 return FunctionValType(FT->getReturnType(), ParamTypes, FT->isVarArg());
781 // FunctionType::get - The factory function for the FunctionType class...
782 FunctionType *FunctionType::get(const Type *ReturnType,
783 const std::vector<const Type*> &Params,
785 FunctionValType VT(ReturnType, Params, isVarArg);
786 FunctionType *MT = FunctionTypes.get(VT);
789 FunctionTypes.add(VT, MT = new FunctionType(ReturnType, Params, isVarArg));
791 #ifdef DEBUG_MERGE_TYPES
792 std::cerr << "Derived new type: " << MT << "\n";
797 //===----------------------------------------------------------------------===//
798 // Array Type Factory...
805 ArrayValType(const Type *val, int sz) : ValTy(val), Size(sz) {}
807 static ArrayValType get(const ArrayType *AT) {
808 return ArrayValType(AT->getElementType(), AT->getNumElements());
811 static unsigned hashTypeStructure(const ArrayType *AT) {
812 return AT->getNumElements();
815 // Subclass should override this... to update self as usual
816 void doRefinement(const DerivedType *OldType, const Type *NewType) {
817 assert(ValTy == OldType);
821 inline bool operator<(const ArrayValType &MTV) const {
822 if (Size < MTV.Size) return true;
823 return Size == MTV.Size && ValTy < MTV.ValTy;
827 static TypeMap<ArrayValType, ArrayType> ArrayTypes;
830 ArrayType *ArrayType::get(const Type *ElementType, unsigned NumElements) {
831 assert(ElementType && "Can't get array of null types!");
833 ArrayValType AVT(ElementType, NumElements);
834 ArrayType *AT = ArrayTypes.get(AVT);
835 if (AT) return AT; // Found a match, return it!
837 // Value not found. Derive a new type!
838 ArrayTypes.add(AVT, AT = new ArrayType(ElementType, NumElements));
840 #ifdef DEBUG_MERGE_TYPES
841 std::cerr << "Derived new type: " << *AT << "\n";
846 //===----------------------------------------------------------------------===//
847 // Struct Type Factory...
851 // StructValType - Define a class to hold the key that goes into the TypeMap
853 class StructValType {
854 std::vector<const Type*> ElTypes;
856 StructValType(const std::vector<const Type*> &args) : ElTypes(args) {}
858 static StructValType get(const StructType *ST) {
859 std::vector<const Type *> ElTypes;
860 ElTypes.reserve(ST->getNumElements());
861 for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i)
862 ElTypes.push_back(ST->getElementType(i));
864 return StructValType(ElTypes);
867 static unsigned hashTypeStructure(const StructType *ST) {
868 return ST->getNumElements();
871 // Subclass should override this... to update self as usual
872 void doRefinement(const DerivedType *OldType, const Type *NewType) {
873 for (unsigned i = 0; i < ElTypes.size(); ++i)
874 if (ElTypes[i] == OldType) ElTypes[i] = NewType;
877 inline bool operator<(const StructValType &STV) const {
878 return ElTypes < STV.ElTypes;
883 static TypeMap<StructValType, StructType> StructTypes;
885 StructType *StructType::get(const std::vector<const Type*> &ETypes) {
886 StructValType STV(ETypes);
887 StructType *ST = StructTypes.get(STV);
890 // Value not found. Derive a new type!
891 StructTypes.add(STV, ST = new StructType(ETypes));
893 #ifdef DEBUG_MERGE_TYPES
894 std::cerr << "Derived new type: " << *ST << "\n";
901 //===----------------------------------------------------------------------===//
902 // Pointer Type Factory...
905 // PointerValType - Define a class to hold the key that goes into the TypeMap
908 class PointerValType {
911 PointerValType(const Type *val) : ValTy(val) {}
913 static PointerValType get(const PointerType *PT) {
914 return PointerValType(PT->getElementType());
917 static unsigned hashTypeStructure(const PointerType *PT) {
921 // Subclass should override this... to update self as usual
922 void doRefinement(const DerivedType *OldType, const Type *NewType) {
923 assert(ValTy == OldType);
927 bool operator<(const PointerValType &MTV) const {
928 return ValTy < MTV.ValTy;
933 static TypeMap<PointerValType, PointerType> PointerTypes;
935 PointerType *PointerType::get(const Type *ValueType) {
936 assert(ValueType && "Can't get a pointer to <null> type!");
937 PointerValType PVT(ValueType);
939 PointerType *PT = PointerTypes.get(PVT);
942 // Value not found. Derive a new type!
943 PointerTypes.add(PVT, PT = new PointerType(ValueType));
945 #ifdef DEBUG_MERGE_TYPES
946 std::cerr << "Derived new type: " << *PT << "\n";
952 //===----------------------------------------------------------------------===//
953 // Derived Type Refinement Functions
954 //===----------------------------------------------------------------------===//
956 // removeAbstractTypeUser - Notify an abstract type that a user of the class
957 // no longer has a handle to the type. This function is called primarily by
958 // the PATypeHandle class. When there are no users of the abstract type, it
959 // is annihilated, because there is no way to get a reference to it ever again.
961 void DerivedType::removeAbstractTypeUser(AbstractTypeUser *U) const {
962 // Search from back to front because we will notify users from back to
963 // front. Also, it is likely that there will be a stack like behavior to
964 // users that register and unregister users.
967 for (i = AbstractTypeUsers.size(); AbstractTypeUsers[i-1] != U; --i)
968 assert(i != 0 && "AbstractTypeUser not in user list!");
970 --i; // Convert to be in range 0 <= i < size()
971 assert(i < AbstractTypeUsers.size() && "Index out of range!"); // Wraparound?
973 AbstractTypeUsers.erase(AbstractTypeUsers.begin()+i);
975 #ifdef DEBUG_MERGE_TYPES
976 std::cerr << " remAbstractTypeUser[" << (void*)this << ", "
977 << *this << "][" << i << "] User = " << U << "\n";
980 if (AbstractTypeUsers.empty() && getRefCount() == 0 && isAbstract()) {
981 #ifdef DEBUG_MERGE_TYPES
982 std::cerr << "DELETEing unused abstract type: <" << *this
983 << ">[" << (void*)this << "]" << "\n";
985 delete this; // No users of this abstract type!
990 // refineAbstractTypeTo - This function is used to when it is discovered that
991 // the 'this' abstract type is actually equivalent to the NewType specified.
992 // This causes all users of 'this' to switch to reference the more concrete type
993 // NewType and for 'this' to be deleted.
995 void DerivedType::refineAbstractTypeTo(const Type *NewType) {
996 assert(isAbstract() && "refineAbstractTypeTo: Current type is not abstract!");
997 assert(this != NewType && "Can't refine to myself!");
998 assert(ForwardType == 0 && "This type has already been refined!");
1000 // The descriptions may be out of date. Conservatively clear them all!
1001 AbstractTypeDescriptions.clear();
1003 #ifdef DEBUG_MERGE_TYPES
1004 std::cerr << "REFINING abstract type [" << (void*)this << " "
1005 << *this << "] to [" << (void*)NewType << " "
1006 << *NewType << "]!\n";
1009 // Make sure to put the type to be refined to into a holder so that if IT gets
1010 // refined, that we will not continue using a dead reference...
1012 PATypeHolder NewTy(NewType);
1014 // Any PATypeHolders referring to this type will now automatically forward to
1015 // the type we are resolved to.
1016 ForwardType = NewType;
1017 if (NewType->isAbstract())
1018 cast<DerivedType>(NewType)->addRef();
1020 // Add a self use of the current type so that we don't delete ourself until
1021 // after the function exits.
1023 PATypeHolder CurrentTy(this);
1025 // To make the situation simpler, we ask the subclass to remove this type from
1026 // the type map, and to replace any type uses with uses of non-abstract types.
1027 // This dramatically limits the amount of recursive type trouble we can find
1031 // Iterate over all of the uses of this type, invoking callback. Each user
1032 // should remove itself from our use list automatically. We have to check to
1033 // make sure that NewTy doesn't _become_ 'this'. If it does, resolving types
1034 // will not cause users to drop off of the use list. If we resolve to ourself
1037 while (!AbstractTypeUsers.empty() && NewTy != this) {
1038 AbstractTypeUser *User = AbstractTypeUsers.back();
1040 unsigned OldSize = AbstractTypeUsers.size();
1041 #ifdef DEBUG_MERGE_TYPES
1042 std::cerr << " REFINING user " << OldSize-1 << "[" << (void*)User
1043 << "] of abstract type [" << (void*)this << " "
1044 << *this << "] to [" << (void*)NewTy.get() << " "
1045 << *NewTy << "]!\n";
1047 User->refineAbstractType(this, NewTy);
1049 assert(AbstractTypeUsers.size() != OldSize &&
1050 "AbsTyUser did not remove self from user list!");
1053 // If we were successful removing all users from the type, 'this' will be
1054 // deleted when the last PATypeHolder is destroyed or updated from this type.
1055 // This may occur on exit of this function, as the CurrentTy object is
1059 // notifyUsesThatTypeBecameConcrete - Notify AbstractTypeUsers of this type that
1060 // the current type has transitioned from being abstract to being concrete.
1062 void DerivedType::notifyUsesThatTypeBecameConcrete() {
1063 #ifdef DEBUG_MERGE_TYPES
1064 std::cerr << "typeIsREFINED type: " << (void*)this << " " << *this << "\n";
1067 unsigned OldSize = AbstractTypeUsers.size();
1068 while (!AbstractTypeUsers.empty()) {
1069 AbstractTypeUser *ATU = AbstractTypeUsers.back();
1070 ATU->typeBecameConcrete(this);
1072 assert(AbstractTypeUsers.size() < OldSize-- &&
1073 "AbstractTypeUser did not remove itself from the use list!");
1080 // refineAbstractType - Called when a contained type is found to be more
1081 // concrete - this could potentially change us from an abstract type to a
1084 void FunctionType::refineAbstractType(const DerivedType *OldType,
1085 const Type *NewType) {
1086 FunctionTypes.finishRefinement(this, OldType, NewType);
1089 void FunctionType::typeBecameConcrete(const DerivedType *AbsTy) {
1090 refineAbstractType(AbsTy, AbsTy);
1094 // refineAbstractType - Called when a contained type is found to be more
1095 // concrete - this could potentially change us from an abstract type to a
1098 void ArrayType::refineAbstractType(const DerivedType *OldType,
1099 const Type *NewType) {
1100 ArrayTypes.finishRefinement(this, OldType, NewType);
1103 void ArrayType::typeBecameConcrete(const DerivedType *AbsTy) {
1104 refineAbstractType(AbsTy, AbsTy);
1108 // refineAbstractType - Called when a contained type is found to be more
1109 // concrete - this could potentially change us from an abstract type to a
1112 void StructType::refineAbstractType(const DerivedType *OldType,
1113 const Type *NewType) {
1114 StructTypes.finishRefinement(this, OldType, NewType);
1117 void StructType::typeBecameConcrete(const DerivedType *AbsTy) {
1118 refineAbstractType(AbsTy, AbsTy);
1121 // refineAbstractType - Called when a contained type is found to be more
1122 // concrete - this could potentially change us from an abstract type to a
1125 void PointerType::refineAbstractType(const DerivedType *OldType,
1126 const Type *NewType) {
1127 PointerTypes.finishRefinement(this, OldType, NewType);
1130 void PointerType::typeBecameConcrete(const DerivedType *AbsTy) {
1131 refineAbstractType(AbsTy, AbsTy);