1 //===-- ConstantHandling.h - Stuff for manipulating constants ----*- C++ -*--=//
3 // This file contains the declarations of some cool operators that allow you
4 // to do natural things with constant pool values.
6 // Unfortunately we can't overload operators on pointer types (like this:)
8 // inline bool operator==(const ConstPoolVal *V1, const ConstPoolVal *V2)
10 // so we must make due with references, even though it leads to some butt ugly
11 // looking code downstream. *sigh* (ex: ConstPoolVal *Result = *V1 + *v2; )
13 //===----------------------------------------------------------------------===//
15 // WARNING: These operators return pointers to newly 'new'd objects. You MUST
16 // make sure to free them if you don't want them hanging around. Also,
17 // note that these may return a null object if I don't know how to
18 // perform those operations on the specified constant types.
20 //===----------------------------------------------------------------------===//
22 // Implementation notes:
23 // This library is implemented this way for a reason: In most cases, we do
24 // not want to have to link the constant mucking code into an executable.
25 // We do, however want to tie some of this into the main type system, as an
26 // optional component. By using a mutable cache member in the Type class, we
27 // get exactly the kind of behavior we want.
29 // In the end, we get performance almost exactly the same as having a virtual
30 // function dispatch, but we don't have to put our virtual functions into the
31 // "Type" class, and we can implement functionality with templates. Good deal.
33 //===----------------------------------------------------------------------===//
35 #ifndef LLVM_OPT_CONSTANTHANDLING_H
36 #define LLVM_OPT_CONSTANTHANDLING_H
38 #include "llvm/ConstPoolVals.h"
39 #include "llvm/Type.h"
41 //===----------------------------------------------------------------------===//
42 // Implement == directly...
43 //===----------------------------------------------------------------------===//
45 inline ConstPoolBool *operator==(const ConstPoolVal &V1,
46 const ConstPoolVal &V2) {
47 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
48 return new ConstPoolBool(V1.equals(&V2));
51 //===----------------------------------------------------------------------===//
52 // Implement all other operators indirectly through TypeRules system
53 //===----------------------------------------------------------------------===//
57 inline ConstRules() {} // Can only be subclassed...
60 virtual ConstPoolVal *neg(const ConstPoolVal *V) const = 0;
61 virtual ConstPoolVal *not(const ConstPoolVal *V) const = 0;
63 // Binary Operators...
64 virtual ConstPoolVal *add(const ConstPoolVal *V1,
65 const ConstPoolVal *V2) const = 0;
66 virtual ConstPoolVal *sub(const ConstPoolVal *V1,
67 const ConstPoolVal *V2) const = 0;
69 virtual ConstPoolBool *lessthan(const ConstPoolVal *V1,
70 const ConstPoolVal *V2) const = 0;
72 // ConstRules::get - A type will cache its own type rules if one is needed...
73 // we just want to make sure to hit the cache instead of doing it indirectly,
76 static inline const ConstRules *get(const ConstPoolVal &V) {
77 const ConstRules *Result = V.getType()->getConstRules();
78 return Result ? Result : find(V.getType());
81 static const ConstRules *find(const Type *Ty);
83 ConstRules(const ConstRules &); // Do not implement
84 ConstRules &operator=(const ConstRules &); // Do not implement
88 inline ConstPoolVal *operator-(const ConstPoolVal &V) {
89 return ConstRules::get(V)->neg(&V);
92 inline ConstPoolVal *operator!(const ConstPoolVal &V) {
93 return ConstRules::get(V)->not(&V);
98 inline ConstPoolVal *operator+(const ConstPoolVal &V1, const ConstPoolVal &V2) {
99 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
100 return ConstRules::get(V1)->add(&V1, &V2);
103 inline ConstPoolVal *operator-(const ConstPoolVal &V1, const ConstPoolVal &V2) {
104 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
105 return ConstRules::get(V1)->sub(&V1, &V2);
108 inline ConstPoolBool *operator<(const ConstPoolVal &V1,
109 const ConstPoolVal &V2) {
110 assert(V1.getType() == V2.getType() && "Constant types must be identical!");
111 return ConstRules::get(V1)->lessthan(&V1, &V2);
115 //===----------------------------------------------------------------------===//
116 // Implement 'derived' operators based on what we already have...
117 //===----------------------------------------------------------------------===//
119 inline ConstPoolBool *operator>(const ConstPoolVal &V1,
120 const ConstPoolVal &V2) {
124 inline ConstPoolBool *operator!=(const ConstPoolVal &V1,
125 const ConstPoolVal &V2) {
126 ConstPoolBool *Result = V1 == V2;
127 Result->setValue(!Result->getValue()); // Invert value
128 return Result; // !(V1 == V2)
131 inline ConstPoolBool *operator>=(const ConstPoolVal &V1,
132 const ConstPoolVal &V2) {
133 ConstPoolBool *Result = V1 < V2;
134 Result->setValue(!Result->getValue()); // Invert value
135 return Result; // !(V1 < V2)
138 inline ConstPoolBool *operator<=(const ConstPoolVal &V1,
139 const ConstPoolVal &V2) {
140 ConstPoolBool *Result = V1 > V2;
141 Result->setValue(!Result->getValue()); // Invert value
142 return Result; // !(V1 > V2)