1 //===-- ConstantHandling.h - Stuff for manipulating constants ---*- C++ -*-===//
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 contains the declarations of some cool operators that allow you
11 // to do natural things with constant pool values.
13 // Unfortunately we can't overload operators on pointer types (like this:)
15 // inline bool operator==(const Constant *V1, const Constant *V2)
17 // so we must make due with references, even though it leads to some butt ugly
18 // looking code downstream. *sigh* (ex: Constant *Result = *V1 + *v2; )
20 //===----------------------------------------------------------------------===//
22 // WARNING: These operators may return a null object if I don't know how to
23 // perform the specified operation on the specified constant types.
25 //===----------------------------------------------------------------------===//
27 // Implementation notes:
28 // This library is implemented this way for a reason: In most cases, we do
29 // not want to have to link the constant mucking code into an executable.
30 // We do, however want to tie some of this into the main type system, as an
31 // optional component. By using a mutable cache member in the Type class, we
32 // get exactly the kind of behavior we want.
34 // In the end, we get performance almost exactly the same as having a virtual
35 // function dispatch, but we don't have to put our virtual functions into the
36 // "Type" class, and we can implement functionality with templates. Good deal.
38 //===----------------------------------------------------------------------===//
40 #ifndef LLVM_CONSTANTHANDLING_H
41 #define LLVM_CONSTANTHANDLING_H
43 #include "llvm/Constants.h"
44 #include "llvm/Type.h"
50 //===----------------------------------------------------------------------===//
51 // Implement all other operators indirectly through TypeRules system
52 //===----------------------------------------------------------------------===//
57 // Binary Operators...
58 virtual Constant *add(const Constant *V1, const Constant *V2) const = 0;
59 virtual Constant *sub(const Constant *V1, const Constant *V2) const = 0;
60 virtual Constant *mul(const Constant *V1, const Constant *V2) const = 0;
61 virtual Constant *div(const Constant *V1, const Constant *V2) const = 0;
62 virtual Constant *rem(const Constant *V1, const Constant *V2) const = 0;
63 virtual Constant *op_and(const Constant *V1, const Constant *V2) const = 0;
64 virtual Constant *op_or (const Constant *V1, const Constant *V2) const = 0;
65 virtual Constant *op_xor(const Constant *V1, const Constant *V2) const = 0;
66 virtual Constant *shl(const Constant *V1, const Constant *V2) const = 0;
67 virtual Constant *shr(const Constant *V1, const Constant *V2) const = 0;
69 virtual ConstantBool *lessthan(const Constant *V1,
70 const Constant *V2) const = 0;
71 virtual ConstantBool *equalto(const Constant *V1,
72 const Constant *V2) const = 0;
74 // Casting operators. ick
75 virtual ConstantBool *castToBool (const Constant *V) const = 0;
76 virtual ConstantSInt *castToSByte (const Constant *V) const = 0;
77 virtual ConstantUInt *castToUByte (const Constant *V) const = 0;
78 virtual ConstantSInt *castToShort (const Constant *V) const = 0;
79 virtual ConstantUInt *castToUShort(const Constant *V) const = 0;
80 virtual ConstantSInt *castToInt (const Constant *V) const = 0;
81 virtual ConstantUInt *castToUInt (const Constant *V) const = 0;
82 virtual ConstantSInt *castToLong (const Constant *V) const = 0;
83 virtual ConstantUInt *castToULong (const Constant *V) const = 0;
84 virtual ConstantFP *castToFloat (const Constant *V) const = 0;
85 virtual ConstantFP *castToDouble(const Constant *V) const = 0;
86 virtual Constant *castToPointer(const Constant *V,
87 const PointerType *Ty) const = 0;
89 inline Constant *castTo(const Constant *V, const Type *Ty) const {
90 switch (Ty->getPrimitiveID()) {
91 case Type::BoolTyID: return castToBool(V);
92 case Type::UByteTyID: return castToUByte(V);
93 case Type::SByteTyID: return castToSByte(V);
94 case Type::UShortTyID: return castToUShort(V);
95 case Type::ShortTyID: return castToShort(V);
96 case Type::UIntTyID: return castToUInt(V);
97 case Type::IntTyID: return castToInt(V);
98 case Type::ULongTyID: return castToULong(V);
99 case Type::LongTyID: return castToLong(V);
100 case Type::FloatTyID: return castToFloat(V);
101 case Type::DoubleTyID: return castToDouble(V);
102 case Type::PointerTyID:
103 return castToPointer(V, reinterpret_cast<const PointerType*>(Ty));
108 // ConstRules::get - Return an instance of ConstRules for the specified
109 // constant operands.
111 static ConstRules &get(const Constant &V1, const Constant &V2);
113 ConstRules(const ConstRules &); // Do not implement
114 ConstRules &operator=(const ConstRules &); // Do not implement
117 // Unary operators...
118 inline Constant *operator~(const Constant &V) {
119 assert(V.getType()->isIntegral() && "Cannot invert non-integral constant!");
120 return ConstRules::get(V, V).op_xor(&V,
121 ConstantInt::getAllOnesValue(V.getType()));
124 inline Constant *operator-(const Constant &V) {
125 return ConstRules::get(V, V).sub(Constant::getNullValue(V.getType()), &V);
128 // Standard binary operators...
129 inline Constant *operator+(const Constant &V1, const Constant &V2) {
130 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
131 return ConstRules::get(V1, V2).add(&V1, &V2);
134 inline Constant *operator-(const Constant &V1, const Constant &V2) {
135 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
136 return ConstRules::get(V1, V2).sub(&V1, &V2);
139 inline Constant *operator*(const Constant &V1, const Constant &V2) {
140 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
141 return ConstRules::get(V1, V2).mul(&V1, &V2);
144 inline Constant *operator/(const Constant &V1, const Constant &V2) {
145 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
146 return ConstRules::get(V1, V2).div(&V1, &V2);
149 inline Constant *operator%(const Constant &V1, const Constant &V2) {
150 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
151 return ConstRules::get(V1, V2).rem(&V1, &V2);
154 // Logical Operators...
155 inline Constant *operator&(const Constant &V1, const Constant &V2) {
156 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
157 return ConstRules::get(V1, V2).op_and(&V1, &V2);
160 inline Constant *operator|(const Constant &V1, const Constant &V2) {
161 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
162 return ConstRules::get(V1, V2).op_or(&V1, &V2);
165 inline Constant *operator^(const Constant &V1, const Constant &V2) {
166 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
167 return ConstRules::get(V1, V2).op_xor(&V1, &V2);
170 // Shift Instructions...
171 inline Constant *operator<<(const Constant &V1, const Constant &V2) {
172 assert(V1.getType()->isInteger() && V2.getType() == Type::UByteTy);
173 return ConstRules::get(V1, V2).shl(&V1, &V2);
176 inline Constant *operator>>(const Constant &V1, const Constant &V2) {
177 assert(V1.getType()->isInteger() && V2.getType() == Type::UByteTy);
178 return ConstRules::get(V1, V2).shr(&V1, &V2);
181 inline ConstantBool *operator<(const Constant &V1,
182 const Constant &V2) {
183 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
184 return ConstRules::get(V1, V2).lessthan(&V1, &V2);
187 inline ConstantBool *operator==(const Constant &V1, const Constant &V2) {
188 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
189 return ConstRules::get(V1, V2).equalto(&V1, &V2);
192 //===----------------------------------------------------------------------===//
193 // Implement 'derived' operators based on what we already have...
194 //===----------------------------------------------------------------------===//
196 inline ConstantBool *operator!=(const Constant &V1, const Constant &V2) {
197 if (ConstantBool *V = (V1 == V2))
198 return V->inverted(); // !(V1 == V2)
202 inline ConstantBool *operator>(const Constant &V1,
203 const Constant &V2) {
207 inline ConstantBool *operator>=(const Constant &V1,
208 const Constant &V2) {
209 if (ConstantBool *V = (V1 < V2))
210 return V->inverted(); // !(V1 < V2)
214 inline ConstantBool *operator<=(const Constant &V1,
215 const Constant &V2) {
216 if (ConstantBool *V = (V1 > V2))
217 return V->inverted(); // !(V1 > V2)
222 //===----------------------------------------------------------------------===//
223 // Implement higher level instruction folding type instructions
224 //===----------------------------------------------------------------------===//
226 // ConstantFoldInstruction - Attempt to constant fold the specified instruction.
227 // If successful, the constant result is returned, if not, null is returned.
229 Constant *ConstantFoldInstruction(Instruction *I);
231 // Constant fold various types of instruction...
232 Constant *ConstantFoldCastInstruction(const Constant *V, const Type *DestTy);
233 Constant *ConstantFoldBinaryInstruction(unsigned Opcode, const Constant *V1,
235 Constant *ConstantFoldShiftInstruction(unsigned Opcode, const Constant *V1,
237 Constant *ConstantFoldGetElementPtr(const Constant *C,
238 const std::vector<Constant*> &IdxList);
240 } // End llvm namespace