src/share/vm/oops/constantPoolOop.hpp

Tue, 14 Oct 2008 10:15:33 -0400

author
coleenp
date
Tue, 14 Oct 2008 10:15:33 -0400
changeset 833
443791f333a2
parent 631
d1605aabd0a1
child 866
a45484ea312d
permissions
-rw-r--r--

6700107: java/lang/Class/forName/TooManyDimensions.java crashes with SIGSEGV in c2 compiler with fastdebug
Summary: objArrayKlass::compute_modifier_flags was unnecessarily recursive
Reviewed-by: kamg

duke@435 1 /*
xdono@631 2 * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
duke@435 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435 20 * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435 21 * have any questions.
duke@435 22 *
duke@435 23 */
duke@435 24
duke@435 25 // A constantPool is an array containing class constants as described in the
duke@435 26 // class file.
duke@435 27 //
duke@435 28 // Most of the constant pool entries are written during class parsing, which
duke@435 29 // is safe. For klass and string types, the constant pool entry is
duke@435 30 // modified when the entry is resolved. If a klass or string constant pool
duke@435 31 // entry is read without a lock, only the resolved state guarantees that
duke@435 32 // the entry in the constant pool is a klass or String object and
duke@435 33 // not a symbolOop.
duke@435 34
duke@435 35 class SymbolHashMap;
duke@435 36
coleenp@548 37 class constantPoolOopDesc : public oopDesc {
duke@435 38 friend class VMStructs;
duke@435 39 friend class BytecodeInterpreter; // Directly extracts an oop in the pool for fast instanceof/checkcast
duke@435 40 private:
duke@435 41 typeArrayOop _tags; // the tag array describing the constant pool's contents
duke@435 42 constantPoolCacheOop _cache; // the cache holding interpreter runtime information
duke@435 43 klassOop _pool_holder; // the corresponding class
coleenp@548 44 int _length; // number of elements in the array
duke@435 45 // only set to non-zero if constant pool is merged by RedefineClasses
duke@435 46 int _orig_length;
duke@435 47
duke@435 48 void set_tags(typeArrayOop tags) { oop_store_without_check((oop*)&_tags, tags); }
duke@435 49 void tag_at_put(int which, jbyte t) { tags()->byte_at_put(which, t); }
duke@435 50 void release_tag_at_put(int which, jbyte t) { tags()->release_byte_at_put(which, t); }
duke@435 51
duke@435 52 private:
duke@435 53 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(constantPoolOopDesc)); }
duke@435 54 oop* tags_addr() { return (oop*)&_tags; }
duke@435 55 oop* cache_addr() { return (oop*)&_cache; }
duke@435 56
duke@435 57 oop* obj_at_addr(int which) const {
duke@435 58 assert(is_within_bounds(which), "index out of bounds");
duke@435 59 return (oop*) &base()[which];
duke@435 60 }
duke@435 61
duke@435 62 jint* int_at_addr(int which) const {
duke@435 63 assert(is_within_bounds(which), "index out of bounds");
duke@435 64 return (jint*) &base()[which];
duke@435 65 }
duke@435 66
duke@435 67 jlong* long_at_addr(int which) const {
duke@435 68 assert(is_within_bounds(which), "index out of bounds");
duke@435 69 return (jlong*) &base()[which];
duke@435 70 }
duke@435 71
duke@435 72 jfloat* float_at_addr(int which) const {
duke@435 73 assert(is_within_bounds(which), "index out of bounds");
duke@435 74 return (jfloat*) &base()[which];
duke@435 75 }
duke@435 76
duke@435 77 jdouble* double_at_addr(int which) const {
duke@435 78 assert(is_within_bounds(which), "index out of bounds");
duke@435 79 return (jdouble*) &base()[which];
duke@435 80 }
duke@435 81
duke@435 82 public:
duke@435 83 typeArrayOop tags() const { return _tags; }
duke@435 84
duke@435 85 // Klass holding pool
duke@435 86 klassOop pool_holder() const { return _pool_holder; }
duke@435 87 void set_pool_holder(klassOop k) { oop_store_without_check((oop*)&_pool_holder, (oop) k); }
duke@435 88 oop* pool_holder_addr() { return (oop*)&_pool_holder; }
duke@435 89
duke@435 90 // Interpreter runtime support
duke@435 91 constantPoolCacheOop cache() const { return _cache; }
duke@435 92 void set_cache(constantPoolCacheOop cache){ oop_store((oop*)&_cache, cache); }
duke@435 93
duke@435 94 // Assembly code support
duke@435 95 static int tags_offset_in_bytes() { return offset_of(constantPoolOopDesc, _tags); }
duke@435 96 static int cache_offset_in_bytes() { return offset_of(constantPoolOopDesc, _cache); }
duke@435 97 static int pool_holder_offset_in_bytes() { return offset_of(constantPoolOopDesc, _pool_holder); }
duke@435 98
duke@435 99 // Storing constants
duke@435 100
duke@435 101 void klass_at_put(int which, klassOop k) {
duke@435 102 oop_store_without_check((volatile oop *)obj_at_addr(which), oop(k));
duke@435 103 // The interpreter assumes when the tag is stored, the klass is resolved
duke@435 104 // and the klassOop is a klass rather than a symbolOop, so we need
duke@435 105 // hardware store ordering here.
duke@435 106 release_tag_at_put(which, JVM_CONSTANT_Class);
duke@435 107 if (UseConcMarkSweepGC) {
duke@435 108 // In case the earlier card-mark was consumed by a concurrent
duke@435 109 // marking thread before the tag was updated, redirty the card.
duke@435 110 oop_store_without_check((volatile oop *)obj_at_addr(which), oop(k));
duke@435 111 }
duke@435 112 }
duke@435 113
duke@435 114 // For temporary use while constructing constant pool
duke@435 115 void klass_index_at_put(int which, int name_index) {
duke@435 116 tag_at_put(which, JVM_CONSTANT_ClassIndex);
duke@435 117 *int_at_addr(which) = name_index;
duke@435 118 }
duke@435 119
duke@435 120 // Temporary until actual use
duke@435 121 void unresolved_klass_at_put(int which, symbolOop s) {
duke@435 122 // Overwrite the old index with a GC friendly value so
duke@435 123 // that if GC looks during the transition it won't try
duke@435 124 // to treat a small integer as oop.
duke@435 125 *obj_at_addr(which) = NULL;
duke@435 126 release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass);
duke@435 127 oop_store_without_check(obj_at_addr(which), oop(s));
duke@435 128 }
duke@435 129
duke@435 130 // Temporary until actual use
duke@435 131 void unresolved_string_at_put(int which, symbolOop s) {
duke@435 132 *obj_at_addr(which) = NULL;
duke@435 133 release_tag_at_put(which, JVM_CONSTANT_UnresolvedString);
duke@435 134 oop_store_without_check(obj_at_addr(which), oop(s));
duke@435 135 }
duke@435 136
duke@435 137 void int_at_put(int which, jint i) {
duke@435 138 tag_at_put(which, JVM_CONSTANT_Integer);
duke@435 139 *int_at_addr(which) = i;
duke@435 140 }
duke@435 141
duke@435 142 void long_at_put(int which, jlong l) {
duke@435 143 tag_at_put(which, JVM_CONSTANT_Long);
duke@435 144 // *long_at_addr(which) = l;
duke@435 145 Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l));
duke@435 146 }
duke@435 147
duke@435 148 void float_at_put(int which, jfloat f) {
duke@435 149 tag_at_put(which, JVM_CONSTANT_Float);
duke@435 150 *float_at_addr(which) = f;
duke@435 151 }
duke@435 152
duke@435 153 void double_at_put(int which, jdouble d) {
duke@435 154 tag_at_put(which, JVM_CONSTANT_Double);
duke@435 155 // *double_at_addr(which) = d;
duke@435 156 // u8 temp = *(u8*) &d;
duke@435 157 Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d));
duke@435 158 }
duke@435 159
duke@435 160 void symbol_at_put(int which, symbolOop s) {
duke@435 161 tag_at_put(which, JVM_CONSTANT_Utf8);
duke@435 162 oop_store_without_check(obj_at_addr(which), oop(s));
duke@435 163 }
duke@435 164
duke@435 165 void string_at_put(int which, oop str) {
duke@435 166 oop_store((volatile oop*)obj_at_addr(which), str);
duke@435 167 release_tag_at_put(which, JVM_CONSTANT_String);
duke@435 168 if (UseConcMarkSweepGC) {
duke@435 169 // In case the earlier card-mark was consumed by a concurrent
duke@435 170 // marking thread before the tag was updated, redirty the card.
duke@435 171 oop_store_without_check((volatile oop *)obj_at_addr(which), str);
duke@435 172 }
duke@435 173 }
duke@435 174
duke@435 175 // For temporary use while constructing constant pool
duke@435 176 void string_index_at_put(int which, int string_index) {
duke@435 177 tag_at_put(which, JVM_CONSTANT_StringIndex);
duke@435 178 *int_at_addr(which) = string_index;
duke@435 179 }
duke@435 180
duke@435 181 void field_at_put(int which, int class_index, int name_and_type_index) {
duke@435 182 tag_at_put(which, JVM_CONSTANT_Fieldref);
duke@435 183 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
duke@435 184 }
duke@435 185
duke@435 186 void method_at_put(int which, int class_index, int name_and_type_index) {
duke@435 187 tag_at_put(which, JVM_CONSTANT_Methodref);
duke@435 188 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
duke@435 189 }
duke@435 190
duke@435 191 void interface_method_at_put(int which, int class_index, int name_and_type_index) {
duke@435 192 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref);
duke@435 193 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice
duke@435 194 }
duke@435 195
duke@435 196 void name_and_type_at_put(int which, int name_index, int signature_index) {
duke@435 197 tag_at_put(which, JVM_CONSTANT_NameAndType);
duke@435 198 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice
duke@435 199 }
duke@435 200
duke@435 201 // Tag query
duke@435 202
duke@435 203 constantTag tag_at(int which) const { return (constantTag)tags()->byte_at_acquire(which); }
duke@435 204
duke@435 205 // Whether the entry is a pointer that must be GC'd.
duke@435 206 bool is_pointer_entry(int which) {
duke@435 207 constantTag tag = tag_at(which);
duke@435 208 return tag.is_klass() ||
duke@435 209 tag.is_unresolved_klass() ||
duke@435 210 tag.is_symbol() ||
duke@435 211 tag.is_unresolved_string() ||
duke@435 212 tag.is_string();
duke@435 213 }
duke@435 214
duke@435 215 // Fetching constants
duke@435 216
duke@435 217 klassOop klass_at(int which, TRAPS) {
duke@435 218 constantPoolHandle h_this(THREAD, this);
duke@435 219 return klass_at_impl(h_this, which, CHECK_NULL);
duke@435 220 }
duke@435 221
duke@435 222 symbolOop klass_name_at(int which); // Returns the name, w/o resolving.
duke@435 223
duke@435 224 klassOop resolved_klass_at(int which) { // Used by Compiler
duke@435 225 guarantee(tag_at(which).is_klass(), "Corrupted constant pool");
duke@435 226 // Must do an acquire here in case another thread resolved the klass
duke@435 227 // behind our back, lest we later load stale values thru the oop.
duke@435 228 return klassOop((oop)OrderAccess::load_ptr_acquire(obj_at_addr(which)));
duke@435 229 }
duke@435 230
duke@435 231 // This method should only be used with a cpool lock or during parsing or gc
duke@435 232 symbolOop unresolved_klass_at(int which) { // Temporary until actual use
duke@435 233 symbolOop s = symbolOop((oop)OrderAccess::load_ptr_acquire(obj_at_addr(which)));
duke@435 234 // check that the klass is still unresolved.
duke@435 235 assert(tag_at(which).is_unresolved_klass(), "Corrupted constant pool");
duke@435 236 return s;
duke@435 237 }
duke@435 238
duke@435 239 // RedefineClasses() API support:
duke@435 240 symbolOop klass_at_noresolve(int which) { return klass_name_at(which); }
duke@435 241
duke@435 242 jint int_at(int which) {
duke@435 243 assert(tag_at(which).is_int(), "Corrupted constant pool");
duke@435 244 return *int_at_addr(which);
duke@435 245 }
duke@435 246
duke@435 247 jlong long_at(int which) {
duke@435 248 assert(tag_at(which).is_long(), "Corrupted constant pool");
duke@435 249 // return *long_at_addr(which);
duke@435 250 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
duke@435 251 return *((jlong*)&tmp);
duke@435 252 }
duke@435 253
duke@435 254 jfloat float_at(int which) {
duke@435 255 assert(tag_at(which).is_float(), "Corrupted constant pool");
duke@435 256 return *float_at_addr(which);
duke@435 257 }
duke@435 258
duke@435 259 jdouble double_at(int which) {
duke@435 260 assert(tag_at(which).is_double(), "Corrupted constant pool");
duke@435 261 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
duke@435 262 return *((jdouble*)&tmp);
duke@435 263 }
duke@435 264
duke@435 265 symbolOop symbol_at(int which) {
duke@435 266 assert(tag_at(which).is_utf8(), "Corrupted constant pool");
duke@435 267 return symbolOop(*obj_at_addr(which));
duke@435 268 }
duke@435 269
duke@435 270 oop string_at(int which, TRAPS) {
duke@435 271 constantPoolHandle h_this(THREAD, this);
duke@435 272 return string_at_impl(h_this, which, CHECK_NULL);
duke@435 273 }
duke@435 274
duke@435 275 // only called when we are sure a string entry is already resolved (via an
duke@435 276 // earlier string_at call.
duke@435 277 oop resolved_string_at(int which) {
duke@435 278 assert(tag_at(which).is_string(), "Corrupted constant pool");
duke@435 279 // Must do an acquire here in case another thread resolved the klass
duke@435 280 // behind our back, lest we later load stale values thru the oop.
duke@435 281 return (oop)OrderAccess::load_ptr_acquire(obj_at_addr(which));
duke@435 282 }
duke@435 283
duke@435 284 // This method should only be used with a cpool lock or during parsing or gc
duke@435 285 symbolOop unresolved_string_at(int which) { // Temporary until actual use
duke@435 286 symbolOop s = symbolOop((oop)OrderAccess::load_ptr_acquire(obj_at_addr(which)));
duke@435 287 // check that the string is still unresolved.
duke@435 288 assert(tag_at(which).is_unresolved_string(), "Corrupted constant pool");
duke@435 289 return s;
duke@435 290 }
duke@435 291
duke@435 292 // Returns an UTF8 for a CONSTANT_String entry at a given index.
duke@435 293 // UTF8 char* representation was chosen to avoid conversion of
duke@435 294 // java_lang_Strings at resolved entries into symbolOops
duke@435 295 // or vice versa.
duke@435 296 char* string_at_noresolve(int which);
duke@435 297
duke@435 298 jint name_and_type_at(int which) {
duke@435 299 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool");
duke@435 300 return *int_at_addr(which);
duke@435 301 }
duke@435 302
duke@435 303 // The following methods (klass_ref_at, klass_ref_at_noresolve, name_ref_at,
duke@435 304 // signature_ref_at, klass_ref_index_at, name_and_type_ref_index_at,
duke@435 305 // name_ref_index_at, signature_ref_index_at) all expect constant pool indices
duke@435 306 // from the bytecodes to be passed in, which are actually potentially byte-swapped
duke@435 307 // contstant pool cache indices. See field_or_method_at.
duke@435 308
duke@435 309 // Lookup for entries consisting of (klass_index, name_and_type index)
duke@435 310 klassOop klass_ref_at(int which, TRAPS);
duke@435 311 symbolOop klass_ref_at_noresolve(int which);
duke@435 312 symbolOop name_ref_at(int which);
duke@435 313 symbolOop signature_ref_at(int which); // the type descriptor
duke@435 314
duke@435 315 int klass_ref_index_at(int which);
duke@435 316 int name_and_type_ref_index_at(int which);
duke@435 317
duke@435 318 // Lookup for entries consisting of (name_index, signature_index)
duke@435 319 int name_ref_index_at(int which);
duke@435 320 int signature_ref_index_at(int which);
duke@435 321
duke@435 322 BasicType basic_type_for_signature_at(int which);
duke@435 323
duke@435 324 // Resolve string constants (to prevent allocation during compilation)
duke@435 325 void resolve_string_constants(TRAPS) {
duke@435 326 constantPoolHandle h_this(THREAD, this);
duke@435 327 resolve_string_constants_impl(h_this, CHECK);
duke@435 328 }
duke@435 329
duke@435 330 // Klass name matches name at offset
duke@435 331 bool klass_name_at_matches(instanceKlassHandle k, int which);
duke@435 332
duke@435 333 // Sizing
coleenp@548 334 int length() const { return _length; }
coleenp@548 335 void set_length(int length) { _length = length; }
coleenp@548 336
coleenp@548 337 // Tells whether index is within bounds.
coleenp@548 338 bool is_within_bounds(int index) const {
coleenp@548 339 return 0 <= index && index < length();
coleenp@548 340 }
coleenp@548 341
duke@435 342 static int header_size() { return sizeof(constantPoolOopDesc)/HeapWordSize; }
duke@435 343 static int object_size(int length) { return align_object_size(header_size() + length); }
duke@435 344 int object_size() { return object_size(length()); }
duke@435 345
duke@435 346 friend class constantPoolKlass;
duke@435 347 friend class ClassFileParser;
duke@435 348 friend class SystemDictionary;
duke@435 349
duke@435 350 // Used by compiler to prevent classloading.
duke@435 351 static klassOop klass_at_if_loaded (constantPoolHandle this_oop, int which);
duke@435 352 static klassOop klass_ref_at_if_loaded (constantPoolHandle this_oop, int which);
duke@435 353 // Same as above - but does LinkResolving.
duke@435 354 static klassOop klass_ref_at_if_loaded_check(constantPoolHandle this_oop, int which, TRAPS);
duke@435 355
duke@435 356 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the
duke@435 357 // future by other Java code. These take constant pool indices rather than possibly-byte-swapped
duke@435 358 // constant pool cache indices as do the peer methods above.
duke@435 359 symbolOop uncached_name_ref_at(int which);
duke@435 360 symbolOop uncached_signature_ref_at(int which);
duke@435 361 int uncached_klass_ref_index_at(int which);
duke@435 362 int uncached_name_and_type_ref_index_at(int which);
duke@435 363
duke@435 364 // Sharing
duke@435 365 int pre_resolve_shared_klasses(TRAPS);
duke@435 366 void shared_symbols_iterate(OopClosure* closure0);
duke@435 367 void shared_tags_iterate(OopClosure* closure0);
duke@435 368 void shared_strings_iterate(OopClosure* closure0);
duke@435 369
duke@435 370 // Debugging
duke@435 371 const char* printable_name_at(int which) PRODUCT_RETURN0;
duke@435 372
duke@435 373 private:
duke@435 374
duke@435 375 // Takes either a constant pool cache index in possibly byte-swapped
duke@435 376 // byte order (which comes from the bytecodes after rewriting) or,
duke@435 377 // if "uncached" is true, a vanilla constant pool index
duke@435 378 jint field_or_method_at(int which, bool uncached) {
duke@435 379 int i = -1;
duke@435 380 if (uncached || cache() == NULL) {
duke@435 381 i = which;
duke@435 382 } else {
duke@435 383 // change byte-ordering and go via cache
duke@435 384 i = cache()->entry_at(Bytes::swap_u2(which))->constant_pool_index();
duke@435 385 }
duke@435 386 assert(tag_at(i).is_field_or_method(), "Corrupted constant pool");
duke@435 387 return *int_at_addr(i);
duke@435 388 }
duke@435 389
duke@435 390 // Used while constructing constant pool (only by ClassFileParser)
duke@435 391 jint klass_index_at(int which) {
duke@435 392 assert(tag_at(which).is_klass_index(), "Corrupted constant pool");
duke@435 393 return *int_at_addr(which);
duke@435 394 }
duke@435 395
duke@435 396 jint string_index_at(int which) {
duke@435 397 assert(tag_at(which).is_string_index(), "Corrupted constant pool");
duke@435 398 return *int_at_addr(which);
duke@435 399 }
duke@435 400
duke@435 401 // Performs the LinkResolver checks
duke@435 402 static void verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle klass, TRAPS);
duke@435 403
duke@435 404 // Implementation of methods that needs an exposed 'this' pointer, in order to
duke@435 405 // handle GC while executing the method
duke@435 406 static klassOop klass_at_impl(constantPoolHandle this_oop, int which, TRAPS);
duke@435 407 static oop string_at_impl(constantPoolHandle this_oop, int which, TRAPS);
duke@435 408
duke@435 409 // Resolve string constants (to prevent allocation during compilation)
duke@435 410 static void resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS);
duke@435 411
duke@435 412 public:
duke@435 413 // Merging constantPoolOop support:
duke@435 414 bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS);
duke@435 415 void copy_cp_to(int start_i, int end_i, constantPoolHandle to_cp, int to_i,
duke@435 416 TRAPS);
duke@435 417 void copy_entry_to(int from_i, constantPoolHandle to_cp, int to_i, TRAPS);
duke@435 418 int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS);
duke@435 419 int orig_length() const { return _orig_length; }
duke@435 420 void set_orig_length(int orig_length) { _orig_length = orig_length; }
duke@435 421
duke@435 422
duke@435 423 // JVMTI accesss - GetConstantPool, RetransformClasses, ...
duke@435 424 friend class JvmtiConstantPoolReconstituter;
duke@435 425
duke@435 426 private:
duke@435 427 jint cpool_entry_size(jint idx);
duke@435 428 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap);
duke@435 429
duke@435 430 // Copy cpool bytes into byte array.
duke@435 431 // Returns:
duke@435 432 // int > 0, count of the raw cpool bytes that have been copied
duke@435 433 // 0, OutOfMemory error
duke@435 434 // -1, Internal error
duke@435 435 int copy_cpool_bytes(int cpool_size,
duke@435 436 SymbolHashMap* tbl,
duke@435 437 unsigned char *bytes);
duke@435 438 };
duke@435 439
duke@435 440 class SymbolHashMapEntry : public CHeapObj {
duke@435 441 private:
duke@435 442 unsigned int _hash; // 32-bit hash for item
duke@435 443 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket
duke@435 444 symbolOop _symbol; // 1-st part of the mapping: symbol => value
duke@435 445 u2 _value; // 2-nd part of the mapping: symbol => value
duke@435 446
duke@435 447 public:
duke@435 448 unsigned int hash() const { return _hash; }
duke@435 449 void set_hash(unsigned int hash) { _hash = hash; }
duke@435 450
duke@435 451 SymbolHashMapEntry* next() const { return _next; }
duke@435 452 void set_next(SymbolHashMapEntry* next) { _next = next; }
duke@435 453
duke@435 454 symbolOop symbol() const { return _symbol; }
duke@435 455 void set_symbol(symbolOop sym) { _symbol = sym; }
duke@435 456
duke@435 457 u2 value() const { return _value; }
duke@435 458 void set_value(u2 value) { _value = value; }
duke@435 459
duke@435 460 SymbolHashMapEntry(unsigned int hash, symbolOop symbol, u2 value)
duke@435 461 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {}
duke@435 462
duke@435 463 }; // End SymbolHashMapEntry class
duke@435 464
duke@435 465
duke@435 466 class SymbolHashMapBucket : public CHeapObj {
duke@435 467
duke@435 468 private:
duke@435 469 SymbolHashMapEntry* _entry;
duke@435 470
duke@435 471 public:
duke@435 472 SymbolHashMapEntry* entry() const { return _entry; }
duke@435 473 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; }
duke@435 474 void clear() { _entry = NULL; }
duke@435 475
duke@435 476 }; // End SymbolHashMapBucket class
duke@435 477
duke@435 478
duke@435 479 class SymbolHashMap: public CHeapObj {
duke@435 480
duke@435 481 private:
duke@435 482 // Default number of entries in the table
duke@435 483 enum SymbolHashMap_Constants {
duke@435 484 _Def_HashMap_Size = 256
duke@435 485 };
duke@435 486
duke@435 487 int _table_size;
duke@435 488 SymbolHashMapBucket* _buckets;
duke@435 489
duke@435 490 void initialize_table(int table_size) {
duke@435 491 _table_size = table_size;
duke@435 492 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size);
duke@435 493 for (int index = 0; index < table_size; index++) {
duke@435 494 _buckets[index].clear();
duke@435 495 }
duke@435 496 }
duke@435 497
duke@435 498 public:
duke@435 499
duke@435 500 int table_size() const { return _table_size; }
duke@435 501
duke@435 502 SymbolHashMap() { initialize_table(_Def_HashMap_Size); }
duke@435 503 SymbolHashMap(int table_size) { initialize_table(table_size); }
duke@435 504
duke@435 505 // hash P(31) from Kernighan & Ritchie
duke@435 506 static unsigned int compute_hash(const char* str, int len) {
duke@435 507 unsigned int hash = 0;
duke@435 508 while (len-- > 0) {
duke@435 509 hash = 31*hash + (unsigned) *str;
duke@435 510 str++;
duke@435 511 }
duke@435 512 return hash;
duke@435 513 }
duke@435 514
duke@435 515 SymbolHashMapEntry* bucket(int i) {
duke@435 516 return _buckets[i].entry();
duke@435 517 }
duke@435 518
duke@435 519 void add_entry(symbolOop sym, u2 value);
duke@435 520 SymbolHashMapEntry* find_entry(symbolOop sym);
duke@435 521
duke@435 522 u2 symbol_to_value(symbolOop sym) {
duke@435 523 SymbolHashMapEntry *entry = find_entry(sym);
duke@435 524 return (entry == NULL) ? 0 : entry->value();
duke@435 525 }
duke@435 526
duke@435 527 ~SymbolHashMap() {
duke@435 528 SymbolHashMapEntry* next;
duke@435 529 for (int i = 0; i < _table_size; i++) {
duke@435 530 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
duke@435 531 next = cur->next();
duke@435 532 delete(cur);
duke@435 533 }
duke@435 534 }
duke@435 535 delete _buckets;
duke@435 536 }
duke@435 537 }; // End SymbolHashMap class

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