Thu, 07 Apr 2011 17:02:30 -0700
6981791: remove experimental code for JSR 292
Reviewed-by: twisti
1 /*
2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #ifndef SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
26 #define SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
28 #include "oops/arrayOop.hpp"
29 #include "oops/cpCacheOop.hpp"
30 #include "oops/symbol.hpp"
31 #include "oops/typeArrayOop.hpp"
32 #include "utilities/constantTag.hpp"
33 #ifdef TARGET_ARCH_x86
34 # include "bytes_x86.hpp"
35 #endif
36 #ifdef TARGET_ARCH_sparc
37 # include "bytes_sparc.hpp"
38 #endif
39 #ifdef TARGET_ARCH_zero
40 # include "bytes_zero.hpp"
41 #endif
42 #ifdef TARGET_ARCH_arm
43 # include "bytes_arm.hpp"
44 #endif
45 #ifdef TARGET_ARCH_ppc
46 # include "bytes_ppc.hpp"
47 #endif
49 // A constantPool is an array containing class constants as described in the
50 // class file.
51 //
52 // Most of the constant pool entries are written during class parsing, which
53 // is safe. For klass and string types, the constant pool entry is
54 // modified when the entry is resolved. If a klass or string constant pool
55 // entry is read without a lock, only the resolved state guarantees that
56 // the entry in the constant pool is a klass or String object and
57 // not a Symbol*.
59 class SymbolHashMap;
61 class CPSlot VALUE_OBJ_CLASS_SPEC {
62 intptr_t _ptr;
63 public:
64 CPSlot(intptr_t ptr): _ptr(ptr) {}
65 CPSlot(void* ptr): _ptr((intptr_t)ptr) {}
66 CPSlot(oop ptr): _ptr((intptr_t)ptr) {}
67 CPSlot(Symbol* ptr): _ptr((intptr_t)ptr | 1) {}
69 intptr_t value() { return _ptr; }
70 bool is_oop() { return (_ptr & 1) == 0; }
71 bool is_metadata() { return (_ptr & 1) == 1; }
73 oop get_oop() {
74 assert(is_oop(), "bad call");
75 return oop(_ptr);
76 }
77 Symbol* get_symbol() {
78 assert(is_metadata(), "bad call");
79 return (Symbol*)(_ptr & ~1);
80 }
81 };
83 class constantPoolOopDesc : public oopDesc {
84 friend class VMStructs;
85 friend class BytecodeInterpreter; // Directly extracts an oop in the pool for fast instanceof/checkcast
86 private:
87 typeArrayOop _tags; // the tag array describing the constant pool's contents
88 constantPoolCacheOop _cache; // the cache holding interpreter runtime information
89 klassOop _pool_holder; // the corresponding class
90 typeArrayOop _operands; // for variable-sized (InvokeDynamic) nodes, usually empty
91 int _flags; // a few header bits to describe contents for GC
92 int _length; // number of elements in the array
93 volatile bool _is_conc_safe; // if true, safe for concurrent
94 // GC processing
95 // only set to non-zero if constant pool is merged by RedefineClasses
96 int _orig_length;
98 void set_tags(typeArrayOop tags) { oop_store_without_check((oop*)&_tags, tags); }
99 void tag_at_put(int which, jbyte t) { tags()->byte_at_put(which, t); }
100 void release_tag_at_put(int which, jbyte t) { tags()->release_byte_at_put(which, t); }
102 void set_operands(typeArrayOop operands) { oop_store_without_check((oop*)&_operands, operands); }
104 enum FlagBit {
105 FB_has_invokedynamic = 1,
106 FB_has_pseudo_string = 2
107 };
109 int flags() const { return _flags; }
110 void set_flags(int f) { _flags = f; }
111 bool flag_at(FlagBit fb) const { return (_flags & (1 << (int)fb)) != 0; }
112 void set_flag_at(FlagBit fb);
113 // no clear_flag_at function; they only increase
115 private:
116 intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(constantPoolOopDesc)); }
117 oop* tags_addr() { return (oop*)&_tags; }
118 oop* cache_addr() { return (oop*)&_cache; }
119 oop* operands_addr() { return (oop*)&_operands; }
121 CPSlot slot_at(int which) {
122 assert(is_within_bounds(which), "index out of bounds");
123 // There's a transitional value of zero when converting from
124 // Symbol->0->Klass for G1 when resolving classes and strings.
125 // wait for the value to be non-zero (this is temporary)
126 volatile intptr_t adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which));
127 if (adr == 0 && which != 0) {
128 constantTag t = tag_at(which);
129 if (t.is_unresolved_klass() || t.is_klass() ||
130 t.is_unresolved_string() || t.is_string()) {
131 while ((adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))) == 0);
132 }
133 }
134 return CPSlot(adr);
135 }
137 void slot_at_put(int which, CPSlot s) const {
138 assert(is_within_bounds(which), "index out of bounds");
139 *(intptr_t*)&base()[which] = s.value();
140 }
141 oop* obj_at_addr_raw(int which) const {
142 assert(is_within_bounds(which), "index out of bounds");
143 return (oop*) &base()[which];
144 }
146 void obj_at_put_without_check(int which, oop o) {
147 assert(is_within_bounds(which), "index out of bounds");
148 oop_store_without_check((volatile oop *)obj_at_addr_raw(which), o);
149 }
151 void obj_at_put(int which, oop o) const {
152 assert(is_within_bounds(which), "index out of bounds");
153 oop_store((volatile oop*)obj_at_addr_raw(which), o);
154 }
156 jint* int_at_addr(int which) const {
157 assert(is_within_bounds(which), "index out of bounds");
158 return (jint*) &base()[which];
159 }
161 jlong* long_at_addr(int which) const {
162 assert(is_within_bounds(which), "index out of bounds");
163 return (jlong*) &base()[which];
164 }
166 jfloat* float_at_addr(int which) const {
167 assert(is_within_bounds(which), "index out of bounds");
168 return (jfloat*) &base()[which];
169 }
171 jdouble* double_at_addr(int which) const {
172 assert(is_within_bounds(which), "index out of bounds");
173 return (jdouble*) &base()[which];
174 }
176 public:
177 typeArrayOop tags() const { return _tags; }
178 typeArrayOop operands() const { return _operands; }
180 bool has_pseudo_string() const { return flag_at(FB_has_pseudo_string); }
181 bool has_invokedynamic() const { return flag_at(FB_has_invokedynamic); }
182 void set_pseudo_string() { set_flag_at(FB_has_pseudo_string); }
183 void set_invokedynamic() { set_flag_at(FB_has_invokedynamic); }
185 // Klass holding pool
186 klassOop pool_holder() const { return _pool_holder; }
187 void set_pool_holder(klassOop k) { oop_store_without_check((oop*)&_pool_holder, (oop) k); }
188 oop* pool_holder_addr() { return (oop*)&_pool_holder; }
190 // Interpreter runtime support
191 constantPoolCacheOop cache() const { return _cache; }
192 void set_cache(constantPoolCacheOop cache){ oop_store((oop*)&_cache, cache); }
194 // Assembly code support
195 static int tags_offset_in_bytes() { return offset_of(constantPoolOopDesc, _tags); }
196 static int cache_offset_in_bytes() { return offset_of(constantPoolOopDesc, _cache); }
197 static int operands_offset_in_bytes() { return offset_of(constantPoolOopDesc, _operands); }
198 static int pool_holder_offset_in_bytes() { return offset_of(constantPoolOopDesc, _pool_holder); }
200 // Storing constants
202 void klass_at_put(int which, klassOop k) {
203 // Overwrite the old index with a GC friendly value so
204 // that if G1 looks during the transition during oop_store it won't
205 // assert the symbol is not an oop.
206 *obj_at_addr_raw(which) = NULL;
207 assert(k != NULL, "resolved class shouldn't be null");
208 obj_at_put_without_check(which, k);
209 // The interpreter assumes when the tag is stored, the klass is resolved
210 // and the klassOop is a klass rather than a Symbol*, so we need
211 // hardware store ordering here.
212 release_tag_at_put(which, JVM_CONSTANT_Class);
213 if (UseConcMarkSweepGC) {
214 // In case the earlier card-mark was consumed by a concurrent
215 // marking thread before the tag was updated, redirty the card.
216 obj_at_put_without_check(which, k);
217 }
218 }
220 // For temporary use while constructing constant pool
221 void klass_index_at_put(int which, int name_index) {
222 tag_at_put(which, JVM_CONSTANT_ClassIndex);
223 *int_at_addr(which) = name_index;
224 }
226 // Temporary until actual use
227 void unresolved_klass_at_put(int which, Symbol* s) {
228 release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass);
229 slot_at_put(which, s);
230 }
232 void method_handle_index_at_put(int which, int ref_kind, int ref_index) {
233 tag_at_put(which, JVM_CONSTANT_MethodHandle);
234 *int_at_addr(which) = ((jint) ref_index<<16) | ref_kind;
235 }
237 void method_type_index_at_put(int which, int ref_index) {
238 tag_at_put(which, JVM_CONSTANT_MethodType);
239 *int_at_addr(which) = ref_index;
240 }
242 void invoke_dynamic_at_put(int which, int bootstrap_specifier_index, int name_and_type_index) {
243 tag_at_put(which, JVM_CONSTANT_InvokeDynamic);
244 *int_at_addr(which) = ((jint) name_and_type_index<<16) | bootstrap_specifier_index;
245 }
247 // Temporary until actual use
248 void unresolved_string_at_put(int which, Symbol* s) {
249 release_tag_at_put(which, JVM_CONSTANT_UnresolvedString);
250 slot_at_put(which, s);
251 }
253 void int_at_put(int which, jint i) {
254 tag_at_put(which, JVM_CONSTANT_Integer);
255 *int_at_addr(which) = i;
256 }
258 void long_at_put(int which, jlong l) {
259 tag_at_put(which, JVM_CONSTANT_Long);
260 // *long_at_addr(which) = l;
261 Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l));
262 }
264 void float_at_put(int which, jfloat f) {
265 tag_at_put(which, JVM_CONSTANT_Float);
266 *float_at_addr(which) = f;
267 }
269 void double_at_put(int which, jdouble d) {
270 tag_at_put(which, JVM_CONSTANT_Double);
271 // *double_at_addr(which) = d;
272 // u8 temp = *(u8*) &d;
273 Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d));
274 }
276 Symbol** symbol_at_addr(int which) const {
277 assert(is_within_bounds(which), "index out of bounds");
278 return (Symbol**) &base()[which];
279 }
281 void symbol_at_put(int which, Symbol* s) {
282 assert(s->refcount() != 0, "should have nonzero refcount");
283 tag_at_put(which, JVM_CONSTANT_Utf8);
284 slot_at_put(which, s);
285 }
287 void string_at_put(int which, oop str) {
288 // Overwrite the old index with a GC friendly value so
289 // that if G1 looks during the transition during oop_store it won't
290 // assert the symbol is not an oop.
291 *obj_at_addr_raw(which) = NULL;
292 assert(str != NULL, "resolved string shouldn't be null");
293 obj_at_put(which, str);
294 release_tag_at_put(which, JVM_CONSTANT_String);
295 if (UseConcMarkSweepGC) {
296 // In case the earlier card-mark was consumed by a concurrent
297 // marking thread before the tag was updated, redirty the card.
298 obj_at_put_without_check(which, str);
299 }
300 }
302 void object_at_put(int which, oop str) {
303 obj_at_put(which, str);
304 release_tag_at_put(which, JVM_CONSTANT_Object);
305 if (UseConcMarkSweepGC) {
306 // In case the earlier card-mark was consumed by a concurrent
307 // marking thread before the tag was updated, redirty the card.
308 obj_at_put_without_check(which, str);
309 }
310 }
312 // For temporary use while constructing constant pool
313 void string_index_at_put(int which, int string_index) {
314 tag_at_put(which, JVM_CONSTANT_StringIndex);
315 *int_at_addr(which) = string_index;
316 }
318 void field_at_put(int which, int class_index, int name_and_type_index) {
319 tag_at_put(which, JVM_CONSTANT_Fieldref);
320 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
321 }
323 void method_at_put(int which, int class_index, int name_and_type_index) {
324 tag_at_put(which, JVM_CONSTANT_Methodref);
325 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
326 }
328 void interface_method_at_put(int which, int class_index, int name_and_type_index) {
329 tag_at_put(which, JVM_CONSTANT_InterfaceMethodref);
330 *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice
331 }
333 void name_and_type_at_put(int which, int name_index, int signature_index) {
334 tag_at_put(which, JVM_CONSTANT_NameAndType);
335 *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice
336 }
338 // Tag query
340 constantTag tag_at(int which) const { return (constantTag)tags()->byte_at_acquire(which); }
342 // Whether the entry is a pointer that must be GC'd.
343 bool is_pointer_entry(int which) {
344 constantTag tag = tag_at(which);
345 return tag.is_klass() ||
346 tag.is_string() ||
347 tag.is_object();
348 }
350 // Whether the entry points to an object for ldc (resolved or not)
351 bool is_object_entry(int which) {
352 constantTag tag = tag_at(which);
353 return is_pointer_entry(which) ||
354 tag.is_unresolved_klass() ||
355 tag.is_unresolved_string() ||
356 tag.is_symbol();
357 }
359 // Fetching constants
361 klassOop klass_at(int which, TRAPS) {
362 constantPoolHandle h_this(THREAD, this);
363 return klass_at_impl(h_this, which, CHECK_NULL);
364 }
366 Symbol* klass_name_at(int which); // Returns the name, w/o resolving.
368 klassOop resolved_klass_at(int which) { // Used by Compiler
369 guarantee(tag_at(which).is_klass(), "Corrupted constant pool");
370 // Must do an acquire here in case another thread resolved the klass
371 // behind our back, lest we later load stale values thru the oop.
372 return klassOop(CPSlot(OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_oop());
373 }
375 // This method should only be used with a cpool lock or during parsing or gc
376 Symbol* unresolved_klass_at(int which) { // Temporary until actual use
377 Symbol* s = CPSlot(OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_symbol();
378 // check that the klass is still unresolved.
379 assert(tag_at(which).is_unresolved_klass(), "Corrupted constant pool");
380 return s;
381 }
383 // RedefineClasses() API support:
384 Symbol* klass_at_noresolve(int which) { return klass_name_at(which); }
386 jint int_at(int which) {
387 assert(tag_at(which).is_int(), "Corrupted constant pool");
388 return *int_at_addr(which);
389 }
391 jlong long_at(int which) {
392 assert(tag_at(which).is_long(), "Corrupted constant pool");
393 // return *long_at_addr(which);
394 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
395 return *((jlong*)&tmp);
396 }
398 jfloat float_at(int which) {
399 assert(tag_at(which).is_float(), "Corrupted constant pool");
400 return *float_at_addr(which);
401 }
403 jdouble double_at(int which) {
404 assert(tag_at(which).is_double(), "Corrupted constant pool");
405 u8 tmp = Bytes::get_native_u8((address)&base()[which]);
406 return *((jdouble*)&tmp);
407 }
409 Symbol* symbol_at(int which) {
410 assert(tag_at(which).is_utf8(), "Corrupted constant pool");
411 return slot_at(which).get_symbol();
412 }
414 oop string_at(int which, TRAPS) {
415 constantPoolHandle h_this(THREAD, this);
416 return string_at_impl(h_this, which, CHECK_NULL);
417 }
419 oop object_at(int which) {
420 assert(tag_at(which).is_object(), "Corrupted constant pool");
421 return slot_at(which).get_oop();
422 }
424 // A "pseudo-string" is an non-string oop that has found is way into
425 // a String entry.
426 // Under EnableInvokeDynamic this can happen if the user patches a live
427 // object into a CONSTANT_String entry of an anonymous class.
428 // Method oops internally created for method handles may also
429 // use pseudo-strings to link themselves to related metaobjects.
431 bool is_pseudo_string_at(int which);
433 oop pseudo_string_at(int which) {
434 assert(tag_at(which).is_string(), "Corrupted constant pool");
435 return slot_at(which).get_oop();
436 }
438 void pseudo_string_at_put(int which, oop x) {
439 assert(EnableInvokeDynamic, "");
440 set_pseudo_string(); // mark header
441 assert(tag_at(which).is_string() || tag_at(which).is_unresolved_string(), "Corrupted constant pool");
442 string_at_put(which, x); // this works just fine
443 }
445 // only called when we are sure a string entry is already resolved (via an
446 // earlier string_at call.
447 oop resolved_string_at(int which) {
448 assert(tag_at(which).is_string(), "Corrupted constant pool");
449 // Must do an acquire here in case another thread resolved the klass
450 // behind our back, lest we later load stale values thru the oop.
451 return CPSlot(OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_oop();
452 }
454 // This method should only be used with a cpool lock or during parsing or gc
455 Symbol* unresolved_string_at(int which) { // Temporary until actual use
456 Symbol* s = CPSlot(OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_symbol();
457 // check that the string is still unresolved.
458 assert(tag_at(which).is_unresolved_string(), "Corrupted constant pool");
459 return s;
460 }
462 // Returns an UTF8 for a CONSTANT_String entry at a given index.
463 // UTF8 char* representation was chosen to avoid conversion of
464 // java_lang_Strings at resolved entries into Symbol*s
465 // or vice versa.
466 // Caller is responsible for checking for pseudo-strings.
467 char* string_at_noresolve(int which);
469 jint name_and_type_at(int which) {
470 assert(tag_at(which).is_name_and_type(), "Corrupted constant pool");
471 return *int_at_addr(which);
472 }
474 int method_handle_ref_kind_at(int which) {
475 assert(tag_at(which).is_method_handle(), "Corrupted constant pool");
476 return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits
477 }
478 int method_handle_index_at(int which) {
479 assert(tag_at(which).is_method_handle(), "Corrupted constant pool");
480 return extract_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits
481 }
482 int method_type_index_at(int which) {
483 assert(tag_at(which).is_method_type(), "Corrupted constant pool");
484 return *int_at_addr(which);
485 }
486 // Derived queries:
487 Symbol* method_handle_name_ref_at(int which) {
488 int member = method_handle_index_at(which);
489 return impl_name_ref_at(member, true);
490 }
491 Symbol* method_handle_signature_ref_at(int which) {
492 int member = method_handle_index_at(which);
493 return impl_signature_ref_at(member, true);
494 }
495 int method_handle_klass_index_at(int which) {
496 int member = method_handle_index_at(which);
497 return impl_klass_ref_index_at(member, true);
498 }
499 Symbol* method_type_signature_at(int which) {
500 int sym = method_type_index_at(which);
501 return symbol_at(sym);
502 }
504 int invoke_dynamic_name_and_type_ref_index_at(int which) {
505 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
506 return extract_high_short_from_int(*int_at_addr(which));
507 }
508 int invoke_dynamic_bootstrap_specifier_index(int which) {
509 assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool");
510 return extract_low_short_from_int(*int_at_addr(which));
511 }
512 int invoke_dynamic_operand_base(int which) {
513 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
514 return operand_offset_at(operands(), bootstrap_specifier_index);
515 }
516 // The first part of the operands array consists of an index into the second part.
517 // Extract a 32-bit index value from the first part.
518 static int operand_offset_at(typeArrayOop operands, int bootstrap_specifier_index) {
519 int n = (bootstrap_specifier_index * 2);
520 assert(n >= 0 && n+2 <= operands->length(), "oob");
521 // The first 32-bit index points to the beginning of the second part
522 // of the operands array. Make sure this index is in the first part.
523 DEBUG_ONLY(int second_part = build_int_from_shorts(operands->short_at(0),
524 operands->short_at(1)));
525 assert(second_part == 0 || n+2 <= second_part, "oob (2)");
526 int offset = build_int_from_shorts(operands->short_at(n+0),
527 operands->short_at(n+1));
528 // The offset itself must point into the second part of the array.
529 assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)");
530 return offset;
531 }
532 static void operand_offset_at_put(typeArrayOop operands, int bootstrap_specifier_index, int offset) {
533 int n = bootstrap_specifier_index * 2;
534 assert(n >= 0 && n+2 <= operands->length(), "oob");
535 operands->short_at_put(n+0, extract_low_short_from_int(offset));
536 operands->short_at_put(n+1, extract_high_short_from_int(offset));
537 }
538 static int operand_array_length(typeArrayOop operands) {
539 if (operands == NULL || operands->length() == 0) return 0;
540 int second_part = operand_offset_at(operands, 0);
541 return (second_part / 2);
542 }
544 #ifdef ASSERT
545 // operand tuples fit together exactly, end to end
546 static int operand_limit_at(typeArrayOop operands, int bootstrap_specifier_index) {
547 int nextidx = bootstrap_specifier_index + 1;
548 if (nextidx == operand_array_length(operands))
549 return operands->length();
550 else
551 return operand_offset_at(operands, nextidx);
552 }
553 int invoke_dynamic_operand_limit(int which) {
554 int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
555 return operand_limit_at(operands(), bootstrap_specifier_index);
556 }
557 #endif //ASSERT
559 // layout of InvokeDynamic bootstrap method specifier (in second part of operands array):
560 enum {
561 _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm
562 _indy_argc_offset = 1, // u2 argc
563 _indy_argv_offset = 2 // u2 argv[argc]
564 };
565 int invoke_dynamic_bootstrap_method_ref_index_at(int which) {
566 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
567 int op_base = invoke_dynamic_operand_base(which);
568 return operands()->short_at(op_base + _indy_bsm_offset);
569 }
570 int invoke_dynamic_argument_count_at(int which) {
571 assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
572 int op_base = invoke_dynamic_operand_base(which);
573 int argc = operands()->short_at(op_base + _indy_argc_offset);
574 DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc;
575 int next_offset = invoke_dynamic_operand_limit(which));
576 assert(end_offset == next_offset, "matched ending");
577 return argc;
578 }
579 int invoke_dynamic_argument_index_at(int which, int j) {
580 int op_base = invoke_dynamic_operand_base(which);
581 DEBUG_ONLY(int argc = operands()->short_at(op_base + _indy_argc_offset));
582 assert((uint)j < (uint)argc, "oob");
583 return operands()->short_at(op_base + _indy_argv_offset + j);
584 }
586 // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve,
587 // name_and_type_ref_index_at) all expect to be passed indices obtained
588 // directly from the bytecode.
589 // If the indices are meant to refer to fields or methods, they are
590 // actually rewritten constant pool cache indices.
591 // The routine remap_instruction_operand_from_cache manages the adjustment
592 // of these values back to constant pool indices.
594 // There are also "uncached" versions which do not adjust the operand index; see below.
596 // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear.
597 // In a few cases (the verifier) there are uses before a cpcache has been built,
598 // which are handled by a dynamic check in remap_instruction_operand_from_cache.
599 // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode.
601 // Lookup for entries consisting of (klass_index, name_and_type index)
602 klassOop klass_ref_at(int which, TRAPS);
603 Symbol* klass_ref_at_noresolve(int which);
604 Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); }
605 Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); }
607 int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); }
608 int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); }
610 // Lookup for entries consisting of (name_index, signature_index)
611 int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt)
612 int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt)
614 BasicType basic_type_for_signature_at(int which);
616 // Resolve string constants (to prevent allocation during compilation)
617 void resolve_string_constants(TRAPS) {
618 constantPoolHandle h_this(THREAD, this);
619 resolve_string_constants_impl(h_this, CHECK);
620 }
622 private:
623 enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 };
624 public:
626 // Resolve late bound constants.
627 oop resolve_constant_at(int index, TRAPS) {
628 constantPoolHandle h_this(THREAD, this);
629 return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD);
630 }
632 oop resolve_cached_constant_at(int cache_index, TRAPS) {
633 constantPoolHandle h_this(THREAD, this);
634 return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD);
635 }
637 oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) {
638 constantPoolHandle h_this(THREAD, this);
639 return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD);
640 }
642 // Klass name matches name at offset
643 bool klass_name_at_matches(instanceKlassHandle k, int which);
645 // Sizing
646 int length() const { return _length; }
647 void set_length(int length) { _length = length; }
649 // Tells whether index is within bounds.
650 bool is_within_bounds(int index) const {
651 return 0 <= index && index < length();
652 }
654 static int header_size() { return sizeof(constantPoolOopDesc)/HeapWordSize; }
655 static int object_size(int length) { return align_object_size(header_size() + length); }
656 int object_size() { return object_size(length()); }
658 bool is_conc_safe() { return _is_conc_safe; }
659 void set_is_conc_safe(bool v) { _is_conc_safe = v; }
661 friend class constantPoolKlass;
662 friend class ClassFileParser;
663 friend class SystemDictionary;
665 // Used by compiler to prevent classloading.
666 static klassOop klass_at_if_loaded (constantPoolHandle this_oop, int which);
667 static klassOop klass_ref_at_if_loaded (constantPoolHandle this_oop, int which);
668 // Same as above - but does LinkResolving.
669 static klassOop klass_ref_at_if_loaded_check(constantPoolHandle this_oop, int which, TRAPS);
671 // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the
672 // future by other Java code. These take constant pool indices rather than
673 // constant pool cache indices as do the peer methods above.
674 Symbol* uncached_klass_ref_at_noresolve(int which);
675 Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); }
676 Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); }
677 int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); }
678 int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); }
680 // Sharing
681 int pre_resolve_shared_klasses(TRAPS);
682 void shared_symbols_iterate(SymbolClosure* closure0);
683 void shared_tags_iterate(OopClosure* closure0);
684 void shared_strings_iterate(OopClosure* closure0);
686 // Debugging
687 const char* printable_name_at(int which) PRODUCT_RETURN0;
689 #ifdef ASSERT
690 enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices
691 #else
692 enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op
693 #endif //ASSERT
695 private:
697 Symbol* impl_name_ref_at(int which, bool uncached);
698 Symbol* impl_signature_ref_at(int which, bool uncached);
699 int impl_klass_ref_index_at(int which, bool uncached);
700 int impl_name_and_type_ref_index_at(int which, bool uncached);
702 int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG
704 // Used while constructing constant pool (only by ClassFileParser)
705 jint klass_index_at(int which) {
706 assert(tag_at(which).is_klass_index(), "Corrupted constant pool");
707 return *int_at_addr(which);
708 }
710 jint string_index_at(int which) {
711 assert(tag_at(which).is_string_index(), "Corrupted constant pool");
712 return *int_at_addr(which);
713 }
715 // Performs the LinkResolver checks
716 static void verify_constant_pool_resolve(constantPoolHandle this_oop, KlassHandle klass, TRAPS);
718 // Implementation of methods that needs an exposed 'this' pointer, in order to
719 // handle GC while executing the method
720 static klassOop klass_at_impl(constantPoolHandle this_oop, int which, TRAPS);
721 static oop string_at_impl(constantPoolHandle this_oop, int which, TRAPS);
723 // Resolve string constants (to prevent allocation during compilation)
724 static void resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS);
726 static oop resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS);
728 public:
729 // Merging constantPoolOop support:
730 bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS);
731 void copy_cp_to(int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS) {
732 constantPoolHandle h_this(THREAD, this);
733 copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD);
734 }
735 static void copy_cp_to_impl(constantPoolHandle from_cp, int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS);
736 static void copy_entry_to(constantPoolHandle from_cp, int from_i, constantPoolHandle to_cp, int to_i, TRAPS);
737 int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS);
738 int orig_length() const { return _orig_length; }
739 void set_orig_length(int orig_length) { _orig_length = orig_length; }
741 // Decrease ref counts of symbols that are in the constant pool
742 // when the holder class is unloaded
743 void unreference_symbols();
745 // JVMTI accesss - GetConstantPool, RetransformClasses, ...
746 friend class JvmtiConstantPoolReconstituter;
748 private:
749 jint cpool_entry_size(jint idx);
750 jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap);
752 // Copy cpool bytes into byte array.
753 // Returns:
754 // int > 0, count of the raw cpool bytes that have been copied
755 // 0, OutOfMemory error
756 // -1, Internal error
757 int copy_cpool_bytes(int cpool_size,
758 SymbolHashMap* tbl,
759 unsigned char *bytes);
760 };
762 class SymbolHashMapEntry : public CHeapObj {
763 private:
764 unsigned int _hash; // 32-bit hash for item
765 SymbolHashMapEntry* _next; // Next element in the linked list for this bucket
766 Symbol* _symbol; // 1-st part of the mapping: symbol => value
767 u2 _value; // 2-nd part of the mapping: symbol => value
769 public:
770 unsigned int hash() const { return _hash; }
771 void set_hash(unsigned int hash) { _hash = hash; }
773 SymbolHashMapEntry* next() const { return _next; }
774 void set_next(SymbolHashMapEntry* next) { _next = next; }
776 Symbol* symbol() const { return _symbol; }
777 void set_symbol(Symbol* sym) { _symbol = sym; }
779 u2 value() const { return _value; }
780 void set_value(u2 value) { _value = value; }
782 SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value)
783 : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {}
785 }; // End SymbolHashMapEntry class
788 class SymbolHashMapBucket : public CHeapObj {
790 private:
791 SymbolHashMapEntry* _entry;
793 public:
794 SymbolHashMapEntry* entry() const { return _entry; }
795 void set_entry(SymbolHashMapEntry* entry) { _entry = entry; }
796 void clear() { _entry = NULL; }
798 }; // End SymbolHashMapBucket class
801 class SymbolHashMap: public CHeapObj {
803 private:
804 // Default number of entries in the table
805 enum SymbolHashMap_Constants {
806 _Def_HashMap_Size = 256
807 };
809 int _table_size;
810 SymbolHashMapBucket* _buckets;
812 void initialize_table(int table_size) {
813 _table_size = table_size;
814 _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size);
815 for (int index = 0; index < table_size; index++) {
816 _buckets[index].clear();
817 }
818 }
820 public:
822 int table_size() const { return _table_size; }
824 SymbolHashMap() { initialize_table(_Def_HashMap_Size); }
825 SymbolHashMap(int table_size) { initialize_table(table_size); }
827 // hash P(31) from Kernighan & Ritchie
828 static unsigned int compute_hash(const char* str, int len) {
829 unsigned int hash = 0;
830 while (len-- > 0) {
831 hash = 31*hash + (unsigned) *str;
832 str++;
833 }
834 return hash;
835 }
837 SymbolHashMapEntry* bucket(int i) {
838 return _buckets[i].entry();
839 }
841 void add_entry(Symbol* sym, u2 value);
842 SymbolHashMapEntry* find_entry(Symbol* sym);
844 u2 symbol_to_value(Symbol* sym) {
845 SymbolHashMapEntry *entry = find_entry(sym);
846 return (entry == NULL) ? 0 : entry->value();
847 }
849 ~SymbolHashMap() {
850 SymbolHashMapEntry* next;
851 for (int i = 0; i < _table_size; i++) {
852 for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
853 next = cur->next();
854 delete(cur);
855 }
856 }
857 delete _buckets;
858 }
859 }; // End SymbolHashMap class
861 #endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP