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24 
25 #ifndef SHARE_CI_CICONSTANT_HPP
26 #define SHARE_CI_CICONSTANT_HPP
27 
28 #include "ci/ciClassList.hpp"
29 #include "ci/ciNullObject.hpp"
30 
31 // ciConstant
32 //
33 // This class represents a constant value.
34 class ciConstant {
35   friend class VMStructs;
36 private:
37   friend class ciEnv;
38   friend class ciField;
39 
40   BasicType _type;
41   union {
42     jint      _int;
43     jlong     _long;
44     jfloat    _float;
45     jdouble   _double;
46     ciObject* _object;
47   } _value;
48 
49 public:
50 
ciConstant()51   ciConstant() {
52     _type = T_ILLEGAL; _value._long = -1;
53   }
ciConstant(BasicType type,jint value)54   ciConstant(BasicType type, jint value) {
55     assert(type != T_LONG && type != T_DOUBLE && type != T_FLOAT,
56            "using the wrong ciConstant constructor");
57     _type = type; _value._int = value;
58   }
ciConstant(jlong value)59   ciConstant(jlong value) {
60     _type = T_LONG; _value._long = value;
61   }
ciConstant(jfloat value)62   ciConstant(jfloat value) {
63     _type = T_FLOAT; _value._float = value;
64   }
ciConstant(jdouble value)65   ciConstant(jdouble value) {
66     _type = T_DOUBLE; _value._double = value;
67   }
ciConstant(BasicType type,ciObject * p)68   ciConstant(BasicType type, ciObject* p) {
69     _type = type; _value._object = p;
70   }
71 
basic_type() const72   BasicType basic_type() const { return _type; }
73 
as_boolean()74   jboolean  as_boolean() {
75     assert(basic_type() == T_BOOLEAN, "wrong type");
76     return (jboolean)_value._int;
77   }
as_char()78   jchar     as_char() {
79     assert(basic_type() == T_CHAR, "wrong type");
80     return (jchar)_value._int;
81   }
as_byte()82   jbyte     as_byte() {
83     assert(basic_type() == T_BYTE, "wrong type");
84     return (jbyte)_value._int;
85   }
as_short()86   jshort    as_short() {
87     assert(basic_type() == T_SHORT, "wrong type");
88     return (jshort)_value._int;
89   }
as_int()90   jint      as_int() {
91     assert(basic_type() == T_BOOLEAN || basic_type() == T_CHAR  ||
92            basic_type() == T_BYTE    || basic_type() == T_SHORT ||
93            basic_type() == T_INT, "wrong type");
94     return _value._int;
95   }
as_long()96   jlong     as_long() {
97     assert(basic_type() == T_LONG, "wrong type");
98     return _value._long;
99   }
as_float()100   jfloat    as_float() {
101     assert(basic_type() == T_FLOAT, "wrong type");
102     return _value._float;
103   }
as_double()104   jdouble   as_double() {
105     assert(basic_type() == T_DOUBLE, "wrong type");
106     return _value._double;
107   }
as_object() const108   ciObject* as_object() const {
109     assert(basic_type() == T_OBJECT || basic_type() == T_ARRAY, "wrong type");
110     return _value._object;
111   }
112 
is_null_or_zero() const113   bool      is_null_or_zero() const {
114     if (!is_java_primitive(basic_type())) {
115       return as_object()->is_null_object();
116     } else if (type2size[basic_type()] == 1) {
117       // treat float bits as int, to avoid comparison with -0 and NaN
118       return (_value._int == 0);
119     } else if (type2size[basic_type()] == 2) {
120       // treat double bits as long, to avoid comparison with -0 and NaN
121       return (_value._long == 0);
122     } else {
123       return false;
124     }
125   }
126 
is_valid() const127   bool is_valid() const {
128     return basic_type() != T_ILLEGAL;
129   }
130   // Debugging output
131   void print();
132 };
133 
134 #endif // SHARE_CI_CICONSTANT_HPP
135