1 //===-- Constants.cpp - Implement Constant nodes --------------------------===//
3 // This file implements the Constant* classes...
5 //===----------------------------------------------------------------------===//
7 #include "llvm/Constants.h"
8 #include "llvm/ConstantHandling.h"
9 #include "llvm/DerivedTypes.h"
10 #include "llvm/iMemory.h"
11 #include "llvm/SymbolTable.h"
12 #include "llvm/Module.h"
13 #include "Support/StringExtras.h"
16 ConstantBool *ConstantBool::True = new ConstantBool(true);
17 ConstantBool *ConstantBool::False = new ConstantBool(false);
20 //===----------------------------------------------------------------------===//
22 //===----------------------------------------------------------------------===//
24 // Specialize setName to take care of symbol table majik
25 void Constant::setName(const std::string &Name, SymbolTable *ST) {
26 assert(ST && "Type::setName - Must provide symbol table argument!");
28 if (Name.size()) ST->insert(Name, this);
31 void Constant::destroyConstantImpl() {
32 // When a Constant is destroyed, there may be lingering
33 // references to the constant by other constants in the constant pool. These
34 // constants are implicitly dependant on the module that is being deleted,
35 // but they don't know that. Because we only find out when the CPV is
36 // deleted, we must now notify all of our users (that should only be
37 // Constants) that they are, in fact, invalid now and should be deleted.
39 while (!use_empty()) {
40 Value *V = use_back();
41 #ifndef NDEBUG // Only in -g mode...
42 if (!isa<Constant>(V))
43 std::cerr << "While deleting: " << *this
44 << "\n\nUse still stuck around after Def is destroyed: "
47 assert(isa<Constant>(V) && "References remain to Constant being destroyed");
48 Constant *CPV = cast<Constant>(V);
49 CPV->destroyConstant();
51 // The constant should remove itself from our use list...
52 assert((use_empty() || use_back() != V) && "Constant not removed!");
55 // Value has no outstanding references it is safe to delete it now...
59 // Static constructor to create a '0' constant of arbitrary type...
60 Constant *Constant::getNullValue(const Type *Ty) {
61 switch (Ty->getPrimitiveID()) {
62 case Type::BoolTyID: return ConstantBool::get(false);
66 case Type::LongTyID: return ConstantSInt::get(Ty, 0);
69 case Type::UShortTyID:
71 case Type::ULongTyID: return ConstantUInt::get(Ty, 0);
74 case Type::DoubleTyID: return ConstantFP::get(Ty, 0);
76 case Type::PointerTyID:
77 return ConstantPointerNull::get(cast<PointerType>(Ty));
78 case Type::StructTyID: {
79 const StructType *ST = cast<StructType>(Ty);
81 const StructType::ElementTypes &ETs = ST->getElementTypes();
82 std::vector<Constant*> Elements;
83 Elements.resize(ETs.size());
84 for (unsigned i = 0, e = ETs.size(); i != e; ++i)
85 Elements[i] = Constant::getNullValue(ETs[i]);
86 return ConstantStruct::get(ST, Elements);
88 case Type::ArrayTyID: {
89 const ArrayType *AT = cast<ArrayType>(Ty);
90 Constant *El = Constant::getNullValue(AT->getElementType());
91 unsigned NumElements = AT->getNumElements();
92 return ConstantArray::get(AT, std::vector<Constant*>(NumElements, El));
95 // Function, Type, Label, or Opaque type?
96 assert(0 && "Cannot create a null constant of that type!");
101 // Static constructor to create the maximum constant of an integral type...
102 ConstantIntegral *ConstantIntegral::getMaxValue(const Type *Ty) {
103 switch (Ty->getPrimitiveID()) {
104 case Type::BoolTyID: return ConstantBool::True;
105 case Type::SByteTyID:
106 case Type::ShortTyID:
108 case Type::LongTyID: {
109 // Calculate 011111111111111...
110 unsigned TypeBits = Ty->getPrimitiveSize()*8;
111 int64_t Val = INT64_MAX; // All ones
112 Val >>= 64-TypeBits; // Shift out unwanted 1 bits...
113 return ConstantSInt::get(Ty, Val);
116 case Type::UByteTyID:
117 case Type::UShortTyID:
119 case Type::ULongTyID: return getAllOnesValue(Ty);
125 // Static constructor to create the minimum constant for an integral type...
126 ConstantIntegral *ConstantIntegral::getMinValue(const Type *Ty) {
127 switch (Ty->getPrimitiveID()) {
128 case Type::BoolTyID: return ConstantBool::False;
129 case Type::SByteTyID:
130 case Type::ShortTyID:
132 case Type::LongTyID: {
133 // Calculate 1111111111000000000000
134 unsigned TypeBits = Ty->getPrimitiveSize()*8;
135 int64_t Val = -1; // All ones
136 Val <<= TypeBits-1; // Shift over to the right spot
137 return ConstantSInt::get(Ty, Val);
140 case Type::UByteTyID:
141 case Type::UShortTyID:
143 case Type::ULongTyID: return ConstantUInt::get(Ty, 0);
149 // Static constructor to create an integral constant with all bits set
150 ConstantIntegral *ConstantIntegral::getAllOnesValue(const Type *Ty) {
151 switch (Ty->getPrimitiveID()) {
152 case Type::BoolTyID: return ConstantBool::True;
153 case Type::SByteTyID:
154 case Type::ShortTyID:
156 case Type::LongTyID: return ConstantSInt::get(Ty, -1);
158 case Type::UByteTyID:
159 case Type::UShortTyID:
161 case Type::ULongTyID: {
162 // Calculate ~0 of the right type...
163 unsigned TypeBits = Ty->getPrimitiveSize()*8;
164 uint64_t Val = ~0ULL; // All ones
165 Val >>= 64-TypeBits; // Shift out unwanted 1 bits...
166 return ConstantUInt::get(Ty, Val);
172 bool ConstantUInt::isAllOnesValue() const {
173 unsigned TypeBits = getType()->getPrimitiveSize()*8;
174 uint64_t Val = ~0ULL; // All ones
175 Val >>= 64-TypeBits; // Shift out inappropriate bits
176 return getValue() == Val;
180 //===----------------------------------------------------------------------===//
181 // ConstantXXX Classes
182 //===----------------------------------------------------------------------===//
184 //===----------------------------------------------------------------------===//
185 // Normal Constructors
187 ConstantBool::ConstantBool(bool V) : ConstantIntegral(Type::BoolTy) {
191 ConstantInt::ConstantInt(const Type *Ty, uint64_t V) : ConstantIntegral(Ty) {
195 ConstantSInt::ConstantSInt(const Type *Ty, int64_t V) : ConstantInt(Ty, V) {
196 assert(Ty->isInteger() && Ty->isSigned() &&
197 "Illegal type for unsigned integer constant!");
198 assert(isValueValidForType(Ty, V) && "Value too large for type!");
201 ConstantUInt::ConstantUInt(const Type *Ty, uint64_t V) : ConstantInt(Ty, V) {
202 assert(Ty->isInteger() && Ty->isUnsigned() &&
203 "Illegal type for unsigned integer constant!");
204 assert(isValueValidForType(Ty, V) && "Value too large for type!");
207 ConstantFP::ConstantFP(const Type *Ty, double V) : Constant(Ty) {
208 assert(isValueValidForType(Ty, V) && "Value too large for type!");
212 ConstantArray::ConstantArray(const ArrayType *T,
213 const std::vector<Constant*> &V) : Constant(T) {
214 Operands.reserve(V.size());
215 for (unsigned i = 0, e = V.size(); i != e; ++i) {
216 assert(V[i]->getType() == T->getElementType());
217 Operands.push_back(Use(V[i], this));
221 ConstantStruct::ConstantStruct(const StructType *T,
222 const std::vector<Constant*> &V) : Constant(T) {
223 const StructType::ElementTypes &ETypes = T->getElementTypes();
224 assert(V.size() == ETypes.size() &&
225 "Invalid initializer vector for constant structure");
226 Operands.reserve(V.size());
227 for (unsigned i = 0, e = V.size(); i != e; ++i) {
228 assert((V[i]->getType() == ETypes[i] ||
229 (ETypes[i]->isAbstract() &&
230 ETypes[i]->getPrimitiveID()==V[i]->getType()->getPrimitiveID())) &&
231 "Initializer for struct element doesn't match struct element type!");
232 Operands.push_back(Use(V[i], this));
236 ConstantPointerRef::ConstantPointerRef(GlobalValue *GV)
237 : ConstantPointer(GV->getType()) {
238 Operands.push_back(Use(GV, this));
241 ConstantExpr::ConstantExpr(unsigned Opcode, Constant *C, const Type *Ty)
242 : Constant(Ty), iType(Opcode) {
243 Operands.push_back(Use(C, this));
246 static bool isSetCC(unsigned Opcode) {
247 return Opcode == Instruction::SetEQ || Opcode == Instruction::SetNE ||
248 Opcode == Instruction::SetLT || Opcode == Instruction::SetGT ||
249 Opcode == Instruction::SetLE || Opcode == Instruction::SetGE;
252 ConstantExpr::ConstantExpr(unsigned Opcode, Constant *C1, Constant *C2)
253 : Constant(isSetCC(Opcode) ? Type::BoolTy : C1->getType()), iType(Opcode) {
254 Operands.push_back(Use(C1, this));
255 Operands.push_back(Use(C2, this));
258 ConstantExpr::ConstantExpr(Constant *C, const std::vector<Constant*> &IdxList,
260 : Constant(DestTy), iType(Instruction::GetElementPtr) {
261 Operands.reserve(1+IdxList.size());
262 Operands.push_back(Use(C, this));
263 for (unsigned i = 0, E = IdxList.size(); i != E; ++i)
264 Operands.push_back(Use(IdxList[i], this));
269 //===----------------------------------------------------------------------===//
270 // classof implementations
272 bool ConstantIntegral::classof(const Constant *CPV) {
273 return CPV->getType()->isIntegral() && !isa<ConstantExpr>(CPV);
276 bool ConstantInt::classof(const Constant *CPV) {
277 return CPV->getType()->isInteger() && !isa<ConstantExpr>(CPV);
279 bool ConstantSInt::classof(const Constant *CPV) {
280 return CPV->getType()->isSigned() && !isa<ConstantExpr>(CPV);
282 bool ConstantUInt::classof(const Constant *CPV) {
283 return CPV->getType()->isUnsigned() && !isa<ConstantExpr>(CPV);
285 bool ConstantFP::classof(const Constant *CPV) {
286 const Type *Ty = CPV->getType();
287 return ((Ty == Type::FloatTy || Ty == Type::DoubleTy) &&
288 !isa<ConstantExpr>(CPV));
290 bool ConstantArray::classof(const Constant *CPV) {
291 return isa<ArrayType>(CPV->getType()) && !isa<ConstantExpr>(CPV);
293 bool ConstantStruct::classof(const Constant *CPV) {
294 return isa<StructType>(CPV->getType()) && !isa<ConstantExpr>(CPV);
296 bool ConstantPointer::classof(const Constant *CPV) {
297 return (isa<PointerType>(CPV->getType()) && !isa<ConstantExpr>(CPV));
302 //===----------------------------------------------------------------------===//
303 // isValueValidForType implementations
305 bool ConstantSInt::isValueValidForType(const Type *Ty, int64_t Val) {
306 switch (Ty->getPrimitiveID()) {
308 return false; // These can't be represented as integers!!!
311 case Type::SByteTyID:
312 return (Val <= INT8_MAX && Val >= INT8_MIN);
313 case Type::ShortTyID:
314 return (Val <= INT16_MAX && Val >= INT16_MIN);
316 return (Val <= INT32_MAX && Val >= INT32_MIN);
318 return true; // This is the largest type...
324 bool ConstantUInt::isValueValidForType(const Type *Ty, uint64_t Val) {
325 switch (Ty->getPrimitiveID()) {
327 return false; // These can't be represented as integers!!!
330 case Type::UByteTyID:
331 return (Val <= UINT8_MAX);
332 case Type::UShortTyID:
333 return (Val <= UINT16_MAX);
335 return (Val <= UINT32_MAX);
336 case Type::ULongTyID:
337 return true; // This is the largest type...
343 bool ConstantFP::isValueValidForType(const Type *Ty, double Val) {
344 switch (Ty->getPrimitiveID()) {
346 return false; // These can't be represented as floating point!
348 // TODO: Figure out how to test if a double can be cast to a float!
349 case Type::FloatTyID:
351 return (Val <= UINT8_MAX);
353 case Type::DoubleTyID:
354 return true; // This is the largest type...
358 //===----------------------------------------------------------------------===//
359 // replaceUsesOfWithOnConstant implementations
361 void ConstantArray::replaceUsesOfWithOnConstant(Value *From, Value *To) {
362 assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!");
364 std::vector<Constant*> Values;
365 Values.reserve(getValues().size()); // Build replacement array...
366 for (unsigned i = 0, e = getValues().size(); i != e; ++i) {
367 Constant *Val = cast<Constant>(getValues()[i]);
368 if (Val == From) Val = cast<Constant>(To);
369 Values.push_back(Val);
372 ConstantArray *Replacement = ConstantArray::get(getType(), Values);
373 assert(Replacement != this && "I didn't contain From!");
375 // Everyone using this now uses the replacement...
376 replaceAllUsesWith(Replacement);
378 // Delete the old constant!
382 void ConstantStruct::replaceUsesOfWithOnConstant(Value *From, Value *To) {
383 assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!");
385 std::vector<Constant*> Values;
386 Values.reserve(getValues().size());
387 for (unsigned i = 0, e = getValues().size(); i != e; ++i) {
388 Constant *Val = cast<Constant>(getValues()[i]);
389 if (Val == From) Val = cast<Constant>(To);
390 Values.push_back(Val);
393 ConstantStruct *Replacement = ConstantStruct::get(getType(), Values);
394 assert(Replacement != this && "I didn't contain From!");
396 // Everyone using this now uses the replacement...
397 replaceAllUsesWith(Replacement);
399 // Delete the old constant!
403 void ConstantPointerRef::replaceUsesOfWithOnConstant(Value *From, Value *To) {
404 if (isa<GlobalValue>(To)) {
405 assert(From == getOperand(0) && "Doesn't contain from!");
406 ConstantPointerRef *Replacement =
407 ConstantPointerRef::get(cast<GlobalValue>(To));
409 // Everyone using this now uses the replacement...
410 replaceAllUsesWith(Replacement);
412 // Delete the old constant!
415 // Just replace ourselves with the To value specified.
416 replaceAllUsesWith(To);
418 // Delete the old constant!
423 void ConstantExpr::replaceUsesOfWithOnConstant(Value *From, Value *ToV) {
424 assert(isa<Constant>(ToV) && "Cannot make Constant refer to non-constant!");
425 Constant *To = cast<Constant>(ToV);
427 Constant *Replacement = 0;
428 if (getOpcode() == Instruction::GetElementPtr) {
429 std::vector<Constant*> Indices;
430 Constant *Pointer = getOperand(0);
431 Indices.reserve(getNumOperands()-1);
432 if (Pointer == From) Pointer = To;
434 for (unsigned i = 1, e = getNumOperands(); i != e; ++i) {
435 Constant *Val = getOperand(i);
436 if (Val == From) Val = To;
437 Indices.push_back(Val);
439 Replacement = ConstantExpr::getGetElementPtr(Pointer, Indices);
440 } else if (getOpcode() == Instruction::Cast) {
441 assert(getOperand(0) == From && "Cast only has one use!");
442 Replacement = ConstantExpr::getCast(To, getType());
443 } else if (getNumOperands() == 2) {
444 Constant *C1 = getOperand(0);
445 Constant *C2 = getOperand(1);
446 if (C1 == From) C1 = To;
447 if (C2 == From) C2 = To;
448 Replacement = ConstantExpr::get(getOpcode(), C1, C2);
450 assert(0 && "Unknown ConstantExpr type!");
454 assert(Replacement != this && "I didn't contain From!");
456 // Everyone using this now uses the replacement...
457 replaceAllUsesWith(Replacement);
459 // Delete the old constant!
463 //===----------------------------------------------------------------------===//
464 // Factory Function Implementation
466 // ConstantCreator - A class that is used to create constants by
467 // ValueMap*. This class should be partially specialized if there is
468 // something strange that needs to be done to interface to the ctor for the
471 template<class ConstantClass, class TypeClass, class ValType>
472 struct ConstantCreator {
473 static ConstantClass *create(const TypeClass *Ty, const ValType &V) {
474 return new ConstantClass(Ty, V);
479 template<class ValType, class TypeClass, class ConstantClass>
482 typedef std::pair<const TypeClass*, ValType> ConstHashKey;
483 std::map<ConstHashKey, ConstantClass *> Map;
485 // getOrCreate - Return the specified constant from the map, creating it if
487 ConstantClass *getOrCreate(const TypeClass *Ty, const ValType &V) {
488 ConstHashKey Lookup(Ty, V);
489 typename std::map<ConstHashKey,ConstantClass *>::iterator I =
490 Map.lower_bound(Lookup);
491 if (I != Map.end() && I->first == Lookup)
492 return I->second; // Is it in the map?
494 // If no preexisting value, create one now...
495 ConstantClass *Result =
496 ConstantCreator<ConstantClass,TypeClass,ValType>::create(Ty, V);
498 Map.insert(I, std::make_pair(ConstHashKey(Ty, V), Result));
502 void remove(ConstantClass *CP) {
503 // FIXME: This could be sped up a LOT. If this gets to be a performance
504 // problem, someone should look at this.
505 for (typename std::map<ConstHashKey, ConstantClass*>::iterator
506 I = Map.begin(), E = Map.end(); I != E; ++I)
507 if (I->second == CP) {
511 assert(0 && "Constant not found in constant table!");
518 //---- ConstantUInt::get() and ConstantSInt::get() implementations...
520 static ValueMap< int64_t, Type, ConstantSInt> SIntConstants;
521 static ValueMap<uint64_t, Type, ConstantUInt> UIntConstants;
523 ConstantSInt *ConstantSInt::get(const Type *Ty, int64_t V) {
524 return SIntConstants.getOrCreate(Ty, V);
527 ConstantUInt *ConstantUInt::get(const Type *Ty, uint64_t V) {
528 return UIntConstants.getOrCreate(Ty, V);
531 ConstantInt *ConstantInt::get(const Type *Ty, unsigned char V) {
532 assert(V <= 127 && "Can only be used with very small positive constants!");
533 if (Ty->isSigned()) return ConstantSInt::get(Ty, V);
534 return ConstantUInt::get(Ty, V);
537 //---- ConstantFP::get() implementation...
539 static ValueMap<double, Type, ConstantFP> FPConstants;
541 ConstantFP *ConstantFP::get(const Type *Ty, double V) {
542 return FPConstants.getOrCreate(Ty, V);
545 //---- ConstantArray::get() implementation...
547 static ValueMap<std::vector<Constant*>, ArrayType,
548 ConstantArray> ArrayConstants;
550 ConstantArray *ConstantArray::get(const ArrayType *Ty,
551 const std::vector<Constant*> &V) {
552 return ArrayConstants.getOrCreate(Ty, V);
555 // destroyConstant - Remove the constant from the constant table...
557 void ConstantArray::destroyConstant() {
558 ArrayConstants.remove(this);
559 destroyConstantImpl();
562 /// refineAbstractType - If this callback is invoked, then this constant is of a
563 /// derived type, change all users to use a concrete constant of the new type.
565 void ConstantArray::refineAbstractType(const DerivedType *OldTy,
567 Value::refineAbstractType(OldTy, NewTy);
568 if (OldTy == NewTy) return;
570 // Make everyone now use a constant of the new type...
571 std::vector<Constant*> C;
572 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
573 C.push_back(cast<Constant>(getOperand(i)));
574 Constant *New = ConstantArray::get(cast<ArrayType>(NewTy), C);
576 replaceAllUsesWith(New);
577 destroyConstant(); // This constant is now dead, destroy it.
582 // ConstantArray::get(const string&) - Return an array that is initialized to
583 // contain the specified string. A null terminator is added to the specified
584 // string so that it may be used in a natural way...
586 ConstantArray *ConstantArray::get(const std::string &Str) {
587 std::vector<Constant*> ElementVals;
589 for (unsigned i = 0; i < Str.length(); ++i)
590 ElementVals.push_back(ConstantSInt::get(Type::SByteTy, Str[i]));
592 // Add a null terminator to the string...
593 ElementVals.push_back(ConstantSInt::get(Type::SByteTy, 0));
595 ArrayType *ATy = ArrayType::get(Type::SByteTy, Str.length()+1);
596 return ConstantArray::get(ATy, ElementVals);
599 // getAsString - If the sub-element type of this array is either sbyte or ubyte,
600 // then this method converts the array to an std::string and returns it.
601 // Otherwise, it asserts out.
603 std::string ConstantArray::getAsString() const {
604 assert((getType()->getElementType() == Type::UByteTy ||
605 getType()->getElementType() == Type::SByteTy) && "Not a string!");
608 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
609 Result += (char)cast<ConstantInt>(getOperand(i))->getRawValue();
614 //---- ConstantStruct::get() implementation...
616 static ValueMap<std::vector<Constant*>, StructType,
617 ConstantStruct> StructConstants;
619 ConstantStruct *ConstantStruct::get(const StructType *Ty,
620 const std::vector<Constant*> &V) {
621 return StructConstants.getOrCreate(Ty, V);
624 // destroyConstant - Remove the constant from the constant table...
626 void ConstantStruct::destroyConstant() {
627 StructConstants.remove(this);
628 destroyConstantImpl();
631 /// refineAbstractType - If this callback is invoked, then this constant is of a
632 /// derived type, change all users to use a concrete constant of the new type.
634 void ConstantStruct::refineAbstractType(const DerivedType *OldTy,
636 Value::refineAbstractType(OldTy, NewTy);
637 if (OldTy == NewTy) return;
639 // Make everyone now use a constant of the new type...
640 std::vector<Constant*> C;
641 for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
642 C.push_back(cast<Constant>(getOperand(i)));
643 Constant *New = ConstantStruct::get(cast<StructType>(NewTy), C);
645 replaceAllUsesWith(New);
646 destroyConstant(); // This constant is now dead, destroy it.
651 //---- ConstantPointerNull::get() implementation...
654 // ConstantPointerNull does not take extra "value" argument...
655 template<class ValType>
656 struct ConstantCreator<ConstantPointerNull, PointerType, ValType> {
657 static ConstantPointerNull *create(const PointerType *Ty, const ValType &V){
658 return new ConstantPointerNull(Ty);
662 static ValueMap<char, PointerType, ConstantPointerNull> NullPtrConstants;
664 ConstantPointerNull *ConstantPointerNull::get(const PointerType *Ty) {
665 return NullPtrConstants.getOrCreate(Ty, 0);
668 // destroyConstant - Remove the constant from the constant table...
670 void ConstantPointerNull::destroyConstant() {
671 NullPtrConstants.remove(this);
672 destroyConstantImpl();
675 /// refineAbstractType - If this callback is invoked, then this constant is of a
676 /// derived type, change all users to use a concrete constant of the new type.
678 void ConstantPointerNull::refineAbstractType(const DerivedType *OldTy,
680 Value::refineAbstractType(OldTy, NewTy);
681 if (OldTy == NewTy) return;
683 // Make everyone now use a constant of the new type...
684 Constant *New = ConstantPointerNull::get(cast<PointerType>(NewTy));
686 replaceAllUsesWith(New);
688 // This constant is now dead, destroy it.
695 //---- ConstantPointerRef::get() implementation...
697 ConstantPointerRef *ConstantPointerRef::get(GlobalValue *GV) {
698 assert(GV->getParent() && "Global Value must be attached to a module!");
700 // The Module handles the pointer reference sharing...
701 return GV->getParent()->getConstantPointerRef(GV);
704 // destroyConstant - Remove the constant from the constant table...
706 void ConstantPointerRef::destroyConstant() {
707 getValue()->getParent()->destroyConstantPointerRef(this);
708 destroyConstantImpl();
712 //---- ConstantExpr::get() implementations...
714 typedef std::pair<unsigned, std::vector<Constant*> > ExprMapKeyType;
717 struct ConstantCreator<ConstantExpr, Type, ExprMapKeyType> {
718 static ConstantExpr *create(const Type *Ty, const ExprMapKeyType &V) {
719 if (V.first == Instruction::Cast)
720 return new ConstantExpr(Instruction::Cast, V.second[0], Ty);
721 if ((V.first >= Instruction::BinaryOpsBegin &&
722 V.first < Instruction::BinaryOpsEnd) ||
723 V.first == Instruction::Shl || V.first == Instruction::Shr)
724 return new ConstantExpr(V.first, V.second[0], V.second[1]);
726 assert(V.first == Instruction::GetElementPtr && "Invalid ConstantExpr!");
728 // Check that the indices list is valid...
729 std::vector<Value*> ValIdxList(V.second.begin()+1, V.second.end());
730 const Type *DestTy = GetElementPtrInst::getIndexedType(Ty, ValIdxList,
732 assert(DestTy && "Invalid index list for GetElementPtr expression");
734 std::vector<Constant*> IdxList(V.second.begin()+1, V.second.end());
735 return new ConstantExpr(V.second[0], IdxList, PointerType::get(DestTy));
739 static ValueMap<ExprMapKeyType, Type, ConstantExpr> ExprConstants;
741 Constant *ConstantExpr::getCast(Constant *C, const Type *Ty) {
742 if (Constant *FC = ConstantFoldCastInstruction(C, Ty))
743 return FC; // Fold a few common cases...
745 // Look up the constant in the table first to ensure uniqueness
746 std::vector<Constant*> argVec(1, C);
747 ExprMapKeyType Key = std::make_pair(Instruction::Cast, argVec);
748 return ExprConstants.getOrCreate(Ty, Key);
751 Constant *ConstantExpr::get(unsigned Opcode, Constant *C1, Constant *C2) {
752 // Check the operands for consistency first
753 assert((Opcode >= Instruction::BinaryOpsBegin &&
754 Opcode < Instruction::BinaryOpsEnd) &&
755 "Invalid opcode in binary constant expression");
756 assert(C1->getType() == C2->getType() &&
757 "Operand types in binary constant expression should match");
759 if (Constant *FC = ConstantFoldBinaryInstruction(Opcode, C1, C2))
760 return FC; // Fold a few common cases...
762 std::vector<Constant*> argVec(1, C1); argVec.push_back(C2);
763 ExprMapKeyType Key = std::make_pair(Opcode, argVec);
764 return ExprConstants.getOrCreate(C1->getType(), Key);
767 /// getShift - Return a shift left or shift right constant expr
768 Constant *ConstantExpr::getShift(unsigned Opcode, Constant *C1, Constant *C2) {
769 // Check the operands for consistency first
770 assert((Opcode == Instruction::Shl ||
771 Opcode == Instruction::Shr) &&
772 "Invalid opcode in binary constant expression");
773 assert(C1->getType()->isIntegral() && C2->getType() == Type::UByteTy &&
774 "Invalid operand types for Shift constant expr!");
776 if (Constant *FC = ConstantFoldShiftInstruction(Opcode, C1, C2))
777 return FC; // Fold a few common cases...
779 // Look up the constant in the table first to ensure uniqueness
780 std::vector<Constant*> argVec(1, C1); argVec.push_back(C2);
781 ExprMapKeyType Key = std::make_pair(Opcode, argVec);
782 return ExprConstants.getOrCreate(C1->getType(), Key);
786 Constant *ConstantExpr::getGetElementPtr(Constant *C,
787 const std::vector<Constant*> &IdxList){
788 if (Constant *FC = ConstantFoldGetElementPtr(C, IdxList))
789 return FC; // Fold a few common cases...
790 const Type *Ty = C->getType();
791 assert(isa<PointerType>(Ty) &&
792 "Non-pointer type for constant GetElementPtr expression");
794 // Look up the constant in the table first to ensure uniqueness
795 std::vector<Constant*> argVec(1, C);
796 argVec.insert(argVec.end(), IdxList.begin(), IdxList.end());
798 const ExprMapKeyType &Key = std::make_pair(Instruction::GetElementPtr,argVec);
799 return ExprConstants.getOrCreate(Ty, Key);
802 // destroyConstant - Remove the constant from the constant table...
804 void ConstantExpr::destroyConstant() {
805 ExprConstants.remove(this);
806 destroyConstantImpl();
809 /// refineAbstractType - If this callback is invoked, then this constant is of a
810 /// derived type, change all users to use a concrete constant of the new type.
812 void ConstantExpr::refineAbstractType(const DerivedType *OldTy,
814 Value::refineAbstractType(OldTy, NewTy);
815 if (OldTy == NewTy) return;
817 // FIXME: These need to use a lower-level implementation method, because the
818 // ::get methods intuit the type of the result based on the types of the
819 // operands. The operand types may not have had their types resolved yet.
822 if (getOpcode() == Instruction::Cast) {
823 New = getCast(getOperand(0), NewTy);
824 } else if (getOpcode() >= Instruction::BinaryOpsBegin &&
825 getOpcode() < Instruction::BinaryOpsEnd) {
826 New = get(getOpcode(), getOperand(0), getOperand(0));
827 } else if (getOpcode() == Instruction::Shl || getOpcode() ==Instruction::Shr){
828 New = getShift(getOpcode(), getOperand(0), getOperand(0));
830 assert(getOpcode() == Instruction::GetElementPtr);
832 // Make everyone now use a constant of the new type...
833 std::vector<Constant*> C;
834 for (unsigned i = 1, e = getNumOperands(); i != e; ++i)
835 C.push_back(cast<Constant>(getOperand(i)));
836 New = ConstantExpr::getGetElementPtr(getOperand(0), C);
839 replaceAllUsesWith(New);
840 destroyConstant(); // This constant is now dead, destroy it.
847 const char *ConstantExpr::getOpcodeName() const {
848 return Instruction::getOpcodeName(getOpcode());
851 unsigned Constant::mutateReferences(Value *OldV, Value *NewV) {
852 // Uses of constant pointer refs are global values, not constants!
853 if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(this)) {
854 GlobalValue *NewGV = cast<GlobalValue>(NewV);
855 GlobalValue *OldGV = CPR->getValue();
857 assert(OldGV == OldV && "Cannot mutate old value if I'm not using it!");
859 OldGV->getParent()->mutateConstantPointerRef(OldGV, NewGV);
862 Constant *NewC = cast<Constant>(NewV);
863 unsigned NumReplaced = 0;
864 for (unsigned i = 0, N = getNumOperands(); i != N; ++i)
865 if (Operands[i] == OldV) {