51 private:
52 // Least significant bits of _handle are always 0, so we use these as
53 // the indicator that the _handle is valid. Otherwise, the _data field
54 // contains encoded data (as specified below). Should the VM change
55 // and the lower bits on oops aren't 0, the assert in the constructor
56 // will catch this and we'll have to add a descriminator tag to this
57 // structure.
58 union {
59 Symbol* _sym;
60 uintptr_t _data;
61 } _u;
62
63 enum {
64 // These rest are not found in classfiles, but used by the verifier
65 ITEM_Boolean = 9, ITEM_Byte, ITEM_Short, ITEM_Char,
66 ITEM_Long_2nd, ITEM_Double_2nd
67 };
68
69 // Enum for the _data field
70 enum : uint {
71 // Bottom two bits determine if the type is a reference, primitive,
72 // uninitialized or a query-type.
73 TypeMask = 0x00000003,
74
75 // Topmost types encoding
76 Reference = 0x0, // _sym contains the name
77 Primitive = 0x1, // see below for primitive list
78 Uninitialized = 0x2, // 0x00ffff00 contains bci
79 TypeQuery = 0x3, // Meta-types used for category testing
80
81 // Utility flags
82 ReferenceFlag = 0x00, // For reference query types
83 Category1Flag = 0x01, // One-word values
84 Category2Flag = 0x02, // First word of a two-word value
85 Category2_2ndFlag = 0x04, // Second word of a two-word value
86
87 // special reference values
88 Null = 0x00000000, // A reference with a 0 sym is null
89
90 // Primitives categories (the second byte determines the category)
91 Category1 = (Category1Flag << 1 * BitsPerByte) | Primitive,
92 Category2 = (Category2Flag << 1 * BitsPerByte) | Primitive,
93 Category2_2nd = (Category2_2ndFlag << 1 * BitsPerByte) | Primitive,
94
95 // Primitive values (type descriminator stored in most-signifcant bytes)
96 // Bogus needs the " | Primitive". Else, is_reference(Bogus) returns TRUE.
97 Bogus = (ITEM_Bogus << 2 * BitsPerByte) | Primitive,
98 Boolean = (ITEM_Boolean << 2 * BitsPerByte) | Category1,
99 Byte = (ITEM_Byte << 2 * BitsPerByte) | Category1,
100 Short = (ITEM_Short << 2 * BitsPerByte) | Category1,
101 Char = (ITEM_Char << 2 * BitsPerByte) | Category1,
102 Integer = (ITEM_Integer << 2 * BitsPerByte) | Category1,
103 Float = (ITEM_Float << 2 * BitsPerByte) | Category1,
104 Long = (ITEM_Long << 2 * BitsPerByte) | Category2,
105 Double = (ITEM_Double << 2 * BitsPerByte) | Category2,
106 Long_2nd = (ITEM_Long_2nd << 2 * BitsPerByte) | Category2_2nd,
107 Double_2nd = (ITEM_Double_2nd << 2 * BitsPerByte) | Category2_2nd,
108
109 // Used by Uninitialized (second and third bytes hold the bci)
110 BciMask = 0xffff << 1 * BitsPerByte,
111 BciForThis = ((u2)-1), // A bci of -1 is an Unintialized-This
112
113 // Query values
114 ReferenceQuery = (ReferenceFlag << 1 * BitsPerByte) | TypeQuery,
115 Category1Query = (Category1Flag << 1 * BitsPerByte) | TypeQuery,
116 Category2Query = (Category2Flag << 1 * BitsPerByte) | TypeQuery,
117 Category2_2ndQuery = (Category2_2ndFlag << 1 * BitsPerByte) | TypeQuery
118 };
119
120 VerificationType(uintptr_t raw_data) {
121 _u._data = raw_data;
122 }
123
124 public:
125
126 VerificationType() { *this = bogus_type(); }
127
128 // Create verification types
129 static VerificationType bogus_type() { return VerificationType(Bogus); }
130 static VerificationType top_type() { return bogus_type(); } // alias
131 static VerificationType null_type() { return VerificationType(Null); }
132 static VerificationType integer_type() { return VerificationType(Integer); }
133 static VerificationType float_type() { return VerificationType(Float); }
134 static VerificationType long_type() { return VerificationType(Long); }
135 static VerificationType long2_type() { return VerificationType(Long_2nd); }
136 static VerificationType double_type() { return VerificationType(Double); }
137 static VerificationType boolean_type() { return VerificationType(Boolean); }
138 static VerificationType byte_type() { return VerificationType(Byte); }
139 static VerificationType char_type() { return VerificationType(Char); }
140 static VerificationType short_type() { return VerificationType(Short); }
141 static VerificationType double2_type()
142 { return VerificationType(Double_2nd); }
143
144 // "check" types are used for queries. A "check" type is not assignable
145 // to anything, but the specified types are assignable to a "check". For
146 // example, any category1 primitive is assignable to category1_check and
147 // any reference is assignable to reference_check.
148 static VerificationType reference_check()
149 { return VerificationType(ReferenceQuery); }
150 static VerificationType category1_check()
151 { return VerificationType(Category1Query); }
152 static VerificationType category2_check()
153 { return VerificationType(Category2Query); }
154 static VerificationType category2_2nd_check()
155 { return VerificationType(Category2_2ndQuery); }
156
157 // For reference types, store the actual Symbol
158 static VerificationType reference_type(Symbol* sh) {
159 assert(((uintptr_t)sh & 0x3) == 0, "Symbols must be aligned");
160 // If the above assert fails in the future because oop* isn't aligned,
161 // then this type encoding system will have to change to have a tag value
162 // to discriminate between oops and primitives.
163 return VerificationType((uintptr_t)sh);
164 }
165 static VerificationType uninitialized_type(u2 bci)
166 { return VerificationType(bci << 1 * BitsPerByte | Uninitialized); }
167 static VerificationType uninitialized_this_type()
168 { return uninitialized_type(BciForThis); }
169
170 // Create based on u1 read from classfile
171 static VerificationType from_tag(u1 tag);
172
173 bool is_bogus() const { return (_u._data == Bogus); }
174 bool is_null() const { return (_u._data == Null); }
175 bool is_boolean() const { return (_u._data == Boolean); }
176 bool is_byte() const { return (_u._data == Byte); }
177 bool is_char() const { return (_u._data == Char); }
178 bool is_short() const { return (_u._data == Short); }
179 bool is_integer() const { return (_u._data == Integer); }
180 bool is_long() const { return (_u._data == Long); }
181 bool is_float() const { return (_u._data == Float); }
182 bool is_double() const { return (_u._data == Double); }
183 bool is_long2() const { return (_u._data == Long_2nd); }
184 bool is_double2() const { return (_u._data == Double_2nd); }
185 bool is_reference() const { return ((_u._data & TypeMask) == Reference); }
186 bool is_category1() const {
187 // This should return true for all one-word types, which are category1
188 // primitives, and references (including uninitialized refs). Though
189 // the 'query' types should technically return 'false' here, if we
190 // allow this to return true, we can perform the test using only
191 // 2 operations rather than 8 (3 masks, 3 compares and 2 logical 'ands').
192 // Since no one should call this on a query type anyway, this is ok.
193 assert(!is_check(), "Must not be a check type (wrong value returned)");
194 return ((_u._data & Category1) != Primitive);
195 // should only return false if it's a primitive, and the category1 flag
196 // is not set.
197 }
198 bool is_category2() const { return ((_u._data & Category2) == Category2); }
199 bool is_category2_2nd() const {
200 return ((_u._data & Category2_2nd) == Category2_2nd);
201 }
202 bool is_reference_check() const { return _u._data == ReferenceQuery; }
203 bool is_category1_check() const { return _u._data == Category1Query; }
204 bool is_category2_check() const { return _u._data == Category2Query; }
205 bool is_category2_2nd_check() const { return _u._data == Category2_2ndQuery; }
206 bool is_check() const { return (_u._data & TypeQuery) == TypeQuery; }
207
208 bool is_x_array(char sig) const {
209 return is_null() || (is_array() && (name()->char_at(1) == sig));
210 }
211 bool is_int_array() const { return is_x_array(JVM_SIGNATURE_INT); }
212 bool is_byte_array() const { return is_x_array(JVM_SIGNATURE_BYTE); }
213 bool is_bool_array() const { return is_x_array(JVM_SIGNATURE_BOOLEAN); }
214 bool is_char_array() const { return is_x_array(JVM_SIGNATURE_CHAR); }
215 bool is_short_array() const { return is_x_array(JVM_SIGNATURE_SHORT); }
216 bool is_long_array() const { return is_x_array(JVM_SIGNATURE_LONG); }
217 bool is_float_array() const { return is_x_array(JVM_SIGNATURE_FLOAT); }
218 bool is_double_array() const { return is_x_array(JVM_SIGNATURE_DOUBLE); }
219 bool is_object_array() const { return is_x_array(JVM_SIGNATURE_CLASS); }
220 bool is_array_array() const { return is_x_array(JVM_SIGNATURE_ARRAY); }
221 bool is_reference_array() const
222 { return is_object_array() || is_array_array(); }
223 bool is_object() const
224 { return (is_reference() && !is_null() && name()->utf8_length() >= 1 &&
225 name()->char_at(0) != JVM_SIGNATURE_ARRAY); }
226 bool is_array() const
227 { return (is_reference() && !is_null() && name()->utf8_length() >= 2 &&
228 name()->char_at(0) == JVM_SIGNATURE_ARRAY); }
229 bool is_uninitialized() const
230 { return ((_u._data & Uninitialized) == Uninitialized); }
231 bool is_uninitialized_this() const
232 { return is_uninitialized() && bci() == BciForThis; }
233
234 VerificationType to_category2_2nd() const {
235 assert(is_category2(), "Must be a double word");
236 return VerificationType(is_long() ? Long_2nd : Double_2nd);
237 }
238
239 u2 bci() const {
240 assert(is_uninitialized(), "Must be uninitialized type");
241 return ((_u._data & BciMask) >> 1 * BitsPerByte);
242 }
243
244 Symbol* name() const {
245 assert(is_reference() && !is_null(), "Must be a non-null reference");
246 return _u._sym;
247 }
248
249 bool equals(const VerificationType& t) const {
250 return (_u._data == t._u._data ||
251 (is_reference() && t.is_reference() && !is_null() && !t.is_null() &&
252 name() == t.name()));
253 }
254
255 bool operator ==(const VerificationType& t) const {
256 return equals(t);
257 }
258
259 bool operator !=(const VerificationType& t) const {
260 return !equals(t);
261 }
262
263 // The whole point of this type system - check to see if one type
264 // is assignable to another. Returns true if one can assign 'from' to
265 // this.
266 bool is_assignable_from(
267 const VerificationType& from, ClassVerifier* context,
268 bool from_field_is_protected, TRAPS) const {
269 if (equals(from) || is_bogus()) {
270 return true;
271 } else {
272 switch(_u._data) {
273 case Category1Query:
274 return from.is_category1();
275 case Category2Query:
276 return from.is_category2();
277 case Category2_2ndQuery:
278 return from.is_category2_2nd();
279 case ReferenceQuery:
280 return from.is_reference() || from.is_uninitialized();
281 case Boolean:
282 case Byte:
283 case Char:
284 case Short:
285 // An int can be assigned to boolean, byte, char or short values.
286 return from.is_integer();
287 default:
288 if (is_reference() && from.is_reference()) {
289 return is_reference_assignable_from(from, context,
290 from_field_is_protected,
291 THREAD);
292 } else {
293 return false;
294 }
295 }
296 }
297 }
298
299 // Check to see if one array component type is assignable to another.
300 // Same as is_assignable_from() except int primitives must be identical.
301 bool is_component_assignable_from(
302 const VerificationType& from, ClassVerifier* context,
303 bool from_field_is_protected, TRAPS) const {
304 if (equals(from) || is_bogus()) {
305 return true;
306 } else {
307 switch(_u._data) {
308 case Boolean:
316 }
317 }
318
319 VerificationType get_component(ClassVerifier* context) const;
320
321 int dimensions() const {
322 assert(is_array(), "Must be an array");
323 int index = 0;
324 while (name()->char_at(index) == JVM_SIGNATURE_ARRAY) index++;
325 return index;
326 }
327
328 void print_on(outputStream* st) const;
329
330 private:
331
332 bool is_reference_assignable_from(
333 const VerificationType&, ClassVerifier*, bool from_field_is_protected,
334 TRAPS) const;
335
336 public:
337 static bool resolve_and_check_assignability(InstanceKlass* klass, Symbol* name,
338 Symbol* from_name, bool from_field_is_protected,
339 bool from_is_array, bool from_is_object,
340 TRAPS);
341 };
342
343 #endif // SHARE_CLASSFILE_VERIFICATIONTYPE_HPP
|
51 private:
52 // Least significant bits of _handle are always 0, so we use these as
53 // the indicator that the _handle is valid. Otherwise, the _data field
54 // contains encoded data (as specified below). Should the VM change
55 // and the lower bits on oops aren't 0, the assert in the constructor
56 // will catch this and we'll have to add a descriminator tag to this
57 // structure.
58 union {
59 Symbol* _sym;
60 uintptr_t _data;
61 } _u;
62
63 enum {
64 // These rest are not found in classfiles, but used by the verifier
65 ITEM_Boolean = 9, ITEM_Byte, ITEM_Short, ITEM_Char,
66 ITEM_Long_2nd, ITEM_Double_2nd
67 };
68
69 // Enum for the _data field
70 enum : uint {
71 // Bottom three bits determine if the type is a reference, inline type,
72 // primitive, uninitialized or a query-type.
73 TypeMask = 0x00000007,
74
75 // Topmost types encoding
76 Reference = 0x0, // _sym contains the name of an object
77 Primitive = 0x1, // see below for primitive list
78 Uninitialized = 0x2, // 0x00ffff00 contains bci
79 TypeQuery = 0x3, // Meta-types used for category testing
80 InlineType = 0x4, // _sym contains the name of an inline type
81
82 // Utility flags
83 ReferenceFlag = 0x00, // For reference query types
84 Category1Flag = 0x01, // One-word values
85 Category2Flag = 0x02, // First word of a two-word value
86 Category2_2ndFlag = 0x04, // Second word of a two-word value
87 InlineTypeFlag = 0x08, // For inline type query types
88 NonScalarFlag = 0x10, // For either inline type or reference queries
89
90 // special reference values
91 Null = 0x00000000, // A reference with a 0 sym is null
92
93 // Primitives categories (the second byte determines the category)
94 Category1 = (Category1Flag << 1 * BitsPerByte) | Primitive,
95 Category2 = (Category2Flag << 1 * BitsPerByte) | Primitive,
96 Category2_2nd = (Category2_2ndFlag << 1 * BitsPerByte) | Primitive,
97
98 // Primitive values (type descriminator stored in most-signifcant bytes)
99 // Bogus needs the " | Primitive". Else, is_reference(Bogus) returns TRUE.
100 Bogus = (ITEM_Bogus << 2 * BitsPerByte) | Primitive,
101 Boolean = (ITEM_Boolean << 2 * BitsPerByte) | Category1,
102 Byte = (ITEM_Byte << 2 * BitsPerByte) | Category1,
103 Short = (ITEM_Short << 2 * BitsPerByte) | Category1,
104 Char = (ITEM_Char << 2 * BitsPerByte) | Category1,
105 Integer = (ITEM_Integer << 2 * BitsPerByte) | Category1,
106 Float = (ITEM_Float << 2 * BitsPerByte) | Category1,
107 Long = (ITEM_Long << 2 * BitsPerByte) | Category2,
108 Double = (ITEM_Double << 2 * BitsPerByte) | Category2,
109 Long_2nd = (ITEM_Long_2nd << 2 * BitsPerByte) | Category2_2nd,
110 Double_2nd = (ITEM_Double_2nd << 2 * BitsPerByte) | Category2_2nd,
111
112 // Used by Uninitialized (second and third bytes hold the bci)
113 BciMask = 0xffff << 1 * BitsPerByte,
114 BciForThis = ((u2)-1), // A bci of -1 is an Unintialized-This
115
116 // Query values
117 ReferenceQuery = (ReferenceFlag << 1 * BitsPerByte) | TypeQuery,
118 Category1Query = (Category1Flag << 1 * BitsPerByte) | TypeQuery,
119 Category2Query = (Category2Flag << 1 * BitsPerByte) | TypeQuery,
120 Category2_2ndQuery = (Category2_2ndFlag << 1 * BitsPerByte) | TypeQuery,
121 InlineTypeQuery = (InlineTypeFlag << 1 * BitsPerByte) | TypeQuery,
122 NonScalarQuery = (NonScalarFlag << 1 * BitsPerByte) | TypeQuery
123 };
124
125 VerificationType(uintptr_t raw_data) {
126 _u._data = raw_data;
127 }
128
129 public:
130
131 VerificationType() { *this = bogus_type(); }
132
133 // Create verification types
134 static VerificationType bogus_type() { return VerificationType(Bogus); }
135 static VerificationType top_type() { return bogus_type(); } // alias
136 static VerificationType null_type() { return VerificationType(Null); }
137 static VerificationType integer_type() { return VerificationType(Integer); }
138 static VerificationType float_type() { return VerificationType(Float); }
139 static VerificationType long_type() { return VerificationType(Long); }
140 static VerificationType long2_type() { return VerificationType(Long_2nd); }
141 static VerificationType double_type() { return VerificationType(Double); }
142 static VerificationType boolean_type() { return VerificationType(Boolean); }
143 static VerificationType byte_type() { return VerificationType(Byte); }
144 static VerificationType char_type() { return VerificationType(Char); }
145 static VerificationType short_type() { return VerificationType(Short); }
146 static VerificationType double2_type()
147 { return VerificationType(Double_2nd); }
148
149 // "check" types are used for queries. A "check" type is not assignable
150 // to anything, but the specified types are assignable to a "check". For
151 // example, any category1 primitive is assignable to category1_check and
152 // any reference is assignable to reference_check.
153 static VerificationType reference_check()
154 { return VerificationType(ReferenceQuery); }
155 static VerificationType inline_type_check()
156 { return VerificationType(InlineTypeQuery); }
157 static VerificationType category1_check()
158 { return VerificationType(Category1Query); }
159 static VerificationType category2_check()
160 { return VerificationType(Category2Query); }
161 static VerificationType category2_2nd_check()
162 { return VerificationType(Category2_2ndQuery); }
163 static VerificationType nonscalar_check()
164 { return VerificationType(NonScalarQuery); }
165
166 // For reference types, store the actual Symbol
167 static VerificationType reference_type(Symbol* sh) {
168 assert(((uintptr_t)sh & TypeMask) == 0, "Symbols must be aligned");
169 // If the above assert fails in the future because oop* isn't aligned,
170 // then this type encoding system will have to change to have a tag value
171 // to discriminate between oops and primitives.
172 return VerificationType((uintptr_t)sh);
173 }
174 static VerificationType uninitialized_type(u2 bci)
175 { return VerificationType(bci << 1 * BitsPerByte | Uninitialized); }
176 static VerificationType uninitialized_this_type()
177 { return uninitialized_type(BciForThis); }
178
179 // For inline types, store the actual Symbol* and set the 3rd bit.
180 // Provides a way for an inline type to be distinguished from a reference type.
181 static VerificationType inline_type(Symbol* sh) {
182 assert(((uintptr_t)sh & TypeMask) == 0, "Symbols must be aligned");
183 assert((uintptr_t)sh != 0, "Null is not a valid inline type");
184 // If the above assert fails in the future because oop* isn't aligned,
185 // then this type encoding system will have to change to have a tag value
186 // to discriminate between oops and primitives.
187 return VerificationType((uintptr_t)sh | InlineType);
188 }
189
190 // Create based on u1 read from classfile
191 static VerificationType from_tag(u1 tag);
192
193 bool is_bogus() const { return (_u._data == Bogus); }
194 bool is_null() const { return (_u._data == Null); }
195 bool is_boolean() const { return (_u._data == Boolean); }
196 bool is_byte() const { return (_u._data == Byte); }
197 bool is_char() const { return (_u._data == Char); }
198 bool is_short() const { return (_u._data == Short); }
199 bool is_integer() const { return (_u._data == Integer); }
200 bool is_long() const { return (_u._data == Long); }
201 bool is_float() const { return (_u._data == Float); }
202 bool is_double() const { return (_u._data == Double); }
203 bool is_long2() const { return (_u._data == Long_2nd); }
204 bool is_double2() const { return (_u._data == Double_2nd); }
205 bool is_reference() const { return (((_u._data & TypeMask) == Reference) && !is_inline_type_check()); }
206 bool is_inline_type() const { return ((_u._data & TypeMask) == InlineType); }
207 bool is_category1() const {
208 // This should return true for all one-word types, which are category1
209 // primitives, references (including uninitialized refs) and inline types.
210 // Though the 'query' types should technically return 'false' here, if we
211 // allow this to return true, we can perform the test using only
212 // 2 operations rather than 8 (3 masks, 3 compares and 2 logical 'ands').
213 // Since no one should call this on a query type anyway, this is ok.
214 assert(!is_check(), "Must not be a check type (wrong value returned)");
215 return ((_u._data & Category1) != Primitive);
216 // should only return false if it's a primitive, and the category1 flag
217 // is not set.
218 }
219 bool is_category2() const { return ((_u._data & Category2) == Category2); }
220 bool is_category2_2nd() const {
221 return ((_u._data & Category2_2nd) == Category2_2nd);
222 }
223 bool is_reference_check() const { return _u._data == ReferenceQuery; }
224 bool is_inline_type_check() const { return _u._data == InlineTypeQuery; }
225 bool is_nonscalar_check() const { return _u._data == NonScalarQuery; }
226 bool is_category1_check() const { return _u._data == Category1Query; }
227 bool is_category2_check() const { return _u._data == Category2Query; }
228 bool is_category2_2nd_check() const { return _u._data == Category2_2ndQuery; }
229 bool is_check() const { return (_u._data & TypeQuery) == TypeQuery; }
230
231 bool is_x_array(char sig) const {
232 return is_null() || (is_array() && (name()->char_at(1) == sig));
233 }
234 bool is_int_array() const { return is_x_array(JVM_SIGNATURE_INT); }
235 bool is_byte_array() const { return is_x_array(JVM_SIGNATURE_BYTE); }
236 bool is_bool_array() const { return is_x_array(JVM_SIGNATURE_BOOLEAN); }
237 bool is_char_array() const { return is_x_array(JVM_SIGNATURE_CHAR); }
238 bool is_short_array() const { return is_x_array(JVM_SIGNATURE_SHORT); }
239 bool is_long_array() const { return is_x_array(JVM_SIGNATURE_LONG); }
240 bool is_float_array() const { return is_x_array(JVM_SIGNATURE_FLOAT); }
241 bool is_double_array() const { return is_x_array(JVM_SIGNATURE_DOUBLE); }
242 bool is_object_array() const { return is_x_array(JVM_SIGNATURE_CLASS); }
243 bool is_array_array() const { return is_x_array(JVM_SIGNATURE_ARRAY); }
244 bool is_reference_array() const
245 { return is_object_array() || is_array_array(); }
246 bool is_nonscalar_array() const
247 { return is_object_array() || is_array_array(); }
248 bool is_object() const
249 { return (is_reference() && !is_null() && name()->utf8_length() >= 1 &&
250 name()->char_at(0) != JVM_SIGNATURE_ARRAY); }
251 bool is_array() const
252 { return (is_reference() && !is_null() && name()->utf8_length() >= 2 &&
253 name()->char_at(0) == JVM_SIGNATURE_ARRAY); }
254 bool is_uninitialized() const
255 { return ((_u._data & Uninitialized) == Uninitialized); }
256 bool is_uninitialized_this() const
257 { return is_uninitialized() && bci() == BciForThis; }
258
259 VerificationType to_category2_2nd() const {
260 assert(is_category2(), "Must be a double word");
261 return VerificationType(is_long() ? Long_2nd : Double_2nd);
262 }
263
264 static VerificationType change_ref_to_inline_type(VerificationType ref) {
265 assert(ref.is_reference(), "Bad arg");
266 assert(!ref.is_null(), "Unexpected nullptr");
267 return inline_type(ref.name());
268 }
269
270 u2 bci() const {
271 assert(is_uninitialized(), "Must be uninitialized type");
272 return ((_u._data & BciMask) >> 1 * BitsPerByte);
273 }
274
275 Symbol* name() const {
276 assert(!is_null() && (is_reference() || is_inline_type()), "Must be a non-null reference or an inline type");
277 return (is_reference() ? _u._sym : ((Symbol*)(_u._data & ~(uintptr_t)InlineType)));
278 }
279
280 bool equals(const VerificationType& t) const {
281 return (_u._data == t._u._data ||
282 (((is_reference() && t.is_reference()) ||
283 (is_inline_type() && t.is_inline_type())) &&
284 !is_null() && !t.is_null() && name() == t.name()));
285
286 }
287
288 bool operator ==(const VerificationType& t) const {
289 return equals(t);
290 }
291
292 bool operator !=(const VerificationType& t) const {
293 return !equals(t);
294 }
295
296 // The whole point of this type system - check to see if one type
297 // is assignable to another. Returns true if one can assign 'from' to
298 // this.
299 bool is_assignable_from(
300 const VerificationType& from, ClassVerifier* context,
301 bool from_field_is_protected, TRAPS) const {
302 if (equals(from) || is_bogus()) {
303 return true;
304 } else {
305 switch(_u._data) {
306 case Category1Query:
307 return from.is_category1();
308 case Category2Query:
309 return from.is_category2();
310 case Category2_2ndQuery:
311 return from.is_category2_2nd();
312 case ReferenceQuery:
313 return from.is_reference() || from.is_uninitialized();
314 case NonScalarQuery:
315 return from.is_reference() || from.is_uninitialized() ||
316 from.is_inline_type();
317 case InlineTypeQuery:
318 return from.is_inline_type();
319 case Boolean:
320 case Byte:
321 case Char:
322 case Short:
323 // An int can be assigned to boolean, byte, char or short values.
324 return from.is_integer();
325 default:
326 if (is_inline_type()) {
327 return is_inline_type_assignable_from(from);
328 } else if (is_reference() && from.is_inline_type()) {
329 return is_ref_assignable_from_inline_type(from, context, THREAD);
330 } else if (is_reference() && from.is_reference()) {
331 return is_reference_assignable_from(from, context,
332 from_field_is_protected,
333 THREAD);
334 } else {
335 return false;
336 }
337 }
338 }
339 }
340
341 // Check to see if one array component type is assignable to another.
342 // Same as is_assignable_from() except int primitives must be identical.
343 bool is_component_assignable_from(
344 const VerificationType& from, ClassVerifier* context,
345 bool from_field_is_protected, TRAPS) const {
346 if (equals(from) || is_bogus()) {
347 return true;
348 } else {
349 switch(_u._data) {
350 case Boolean:
358 }
359 }
360
361 VerificationType get_component(ClassVerifier* context) const;
362
363 int dimensions() const {
364 assert(is_array(), "Must be an array");
365 int index = 0;
366 while (name()->char_at(index) == JVM_SIGNATURE_ARRAY) index++;
367 return index;
368 }
369
370 void print_on(outputStream* st) const;
371
372 private:
373
374 bool is_reference_assignable_from(
375 const VerificationType&, ClassVerifier*, bool from_field_is_protected,
376 TRAPS) const;
377
378 bool is_inline_type_assignable_from(const VerificationType& from) const;
379
380 bool is_ref_assignable_from_inline_type(const VerificationType& from, ClassVerifier* context, TRAPS) const;
381
382
383 public:
384 static bool resolve_and_check_assignability(InstanceKlass* klass, Symbol* name,
385 Symbol* from_name, bool from_field_is_protected,
386 bool from_is_array, bool from_is_object,
387 TRAPS);
388 };
389
390 #endif // SHARE_CLASSFILE_VERIFICATIONTYPE_HPP
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