Mon, 25 Jun 2012 21:33:35 -0400
7178670: runtime/7158800/BadUtf8.java fails in SymbolTable::rehash_table
Summary: Cannot delete _buckets and HashtableEntries in shared space (CDS)
Reviewed-by: acorn, kvn, dlong, dcubed, kamg
1 /*
2 * Copyright (c) 2003, 2012, 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_CONSTMETHODOOP_HPP
26 #define SHARE_VM_OOPS_CONSTMETHODOOP_HPP
28 #include "oops/oop.hpp"
29 #include "oops/typeArrayOop.hpp"
31 // An constMethodOop represents portions of a Java method which
32 // do not vary.
33 //
34 // Memory layout (each line represents a word). Note that most
35 // applications load thousands of methods, so keeping the size of this
36 // structure small has a big impact on footprint.
37 //
38 // |------------------------------------------------------|
39 // | header |
40 // | klass |
41 // |------------------------------------------------------|
42 // | fingerprint 1 |
43 // | fingerprint 2 |
44 // | constants (oop) |
45 // | stackmap_data (oop) |
46 // | exception_table (oop) |
47 // | constMethod_size |
48 // | interp_kind | flags | code_size |
49 // | name index | signature index |
50 // | method_idnum | generic_signature_index |
51 // |------------------------------------------------------|
52 // | |
53 // | byte codes |
54 // | |
55 // |------------------------------------------------------|
56 // | compressed linenumber table |
57 // | (see class CompressedLineNumberReadStream) |
58 // | (note that length is unknown until decompressed) |
59 // | (access flags bit tells whether table is present) |
60 // | (indexed from start of constMethodOop) |
61 // | (elements not necessarily sorted!) |
62 // |------------------------------------------------------|
63 // | localvariable table elements + length (length last) |
64 // | (length is u2, elements are 6-tuples of u2) |
65 // | (see class LocalVariableTableElement) |
66 // | (access flags bit tells whether table is present) |
67 // | (indexed from end of contMethodOop) |
68 // |------------------------------------------------------|
69 // | checked exceptions elements + length (length last) |
70 // | (length is u2, elements are u2) |
71 // | (see class CheckedExceptionElement) |
72 // | (access flags bit tells whether table is present) |
73 // | (indexed from end of constMethodOop) |
74 // |------------------------------------------------------|
77 // Utitily class decribing elements in checked exceptions table inlined in methodOop.
78 class CheckedExceptionElement VALUE_OBJ_CLASS_SPEC {
79 public:
80 u2 class_cp_index;
81 };
84 // Utitily class decribing elements in local variable table inlined in methodOop.
85 class LocalVariableTableElement VALUE_OBJ_CLASS_SPEC {
86 public:
87 u2 start_bci;
88 u2 length;
89 u2 name_cp_index;
90 u2 descriptor_cp_index;
91 u2 signature_cp_index;
92 u2 slot;
93 };
96 class constMethodOopDesc : public oopDesc {
97 friend class constMethodKlass;
98 friend class VMStructs;
99 private:
100 enum {
101 _has_linenumber_table = 1,
102 _has_checked_exceptions = 2,
103 _has_localvariable_table = 4
104 };
106 // Bit vector of signature
107 // Callers interpret 0=not initialized yet and
108 // -1=too many args to fix, must parse the slow way.
109 // The real initial value is special to account for nonatomicity of 64 bit
110 // loads and stores. This value may updated and read without a lock by
111 // multiple threads, so is volatile.
112 volatile uint64_t _fingerprint;
113 volatile bool _is_conc_safe; // if true, safe for concurrent GC processing
115 public:
116 oop* oop_block_beg() const { return adr_constants(); }
117 oop* oop_block_end() const { return adr_exception_table() + 1; }
119 private:
120 //
121 // The oop block. See comment in klass.hpp before making changes.
122 //
124 constantPoolOop _constants; // Constant pool
126 // Raw stackmap data for the method
127 typeArrayOop _stackmap_data;
129 // The exception handler table. 4-tuples of ints [start_pc, end_pc,
130 // handler_pc, catch_type index] For methods with no exceptions the
131 // table is pointing to Universe::the_empty_int_array
132 typeArrayOop _exception_table;
134 //
135 // End of the oop block.
136 //
138 int _constMethod_size;
139 jbyte _interpreter_kind;
140 jbyte _flags;
142 // Size of Java bytecodes allocated immediately after methodOop.
143 u2 _code_size;
144 u2 _name_index; // Method name (index in constant pool)
145 u2 _signature_index; // Method signature (index in constant pool)
146 u2 _method_idnum; // unique identification number for the method within the class
147 // initially corresponds to the index into the methods array.
148 // but this may change with redefinition
149 u2 _generic_signature_index; // Generic signature (index in constant pool, 0 if absent)
151 public:
152 // Inlined tables
153 void set_inlined_tables_length(int checked_exceptions_len,
154 int compressed_line_number_size,
155 int localvariable_table_len);
157 bool has_linenumber_table() const
158 { return (_flags & _has_linenumber_table) != 0; }
160 bool has_checked_exceptions() const
161 { return (_flags & _has_checked_exceptions) != 0; }
163 bool has_localvariable_table() const
164 { return (_flags & _has_localvariable_table) != 0; }
166 void set_interpreter_kind(int kind) { _interpreter_kind = kind; }
167 int interpreter_kind(void) const { return _interpreter_kind; }
169 // constant pool
170 constantPoolOop constants() const { return _constants; }
171 void set_constants(constantPoolOop c) {
172 oop_store_without_check((oop*)&_constants, (oop)c);
173 }
175 methodOop method() const;
177 // stackmap table data
178 typeArrayOop stackmap_data() const { return _stackmap_data; }
179 void set_stackmap_data(typeArrayOop sd) {
180 oop_store_without_check((oop*)&_stackmap_data, (oop)sd);
181 }
182 bool has_stackmap_table() const { return _stackmap_data != NULL; }
184 // exception handler table
185 typeArrayOop exception_table() const { return _exception_table; }
186 void set_exception_table(typeArrayOop e) { oop_store_without_check((oop*) &_exception_table, (oop) e); }
187 bool has_exception_handler() const { return exception_table() != NULL && exception_table()->length() > 0; }
189 void init_fingerprint() {
190 const uint64_t initval = CONST64(0x8000000000000000);
191 _fingerprint = initval;
192 }
194 uint64_t fingerprint() const {
195 // Since reads aren't atomic for 64 bits, if any of the high or low order
196 // word is the initial value, return 0. See init_fingerprint for initval.
197 uint high_fp = (uint)(_fingerprint >> 32);
198 if ((int) _fingerprint == 0 || high_fp == 0x80000000) {
199 return 0L;
200 } else {
201 return _fingerprint;
202 }
203 }
205 uint64_t set_fingerprint(uint64_t new_fingerprint) {
206 #ifdef ASSERT
207 // Assert only valid if complete/valid 64 bit _fingerprint value is read.
208 uint64_t oldfp = fingerprint();
209 #endif // ASSERT
210 _fingerprint = new_fingerprint;
211 assert(oldfp == 0L || new_fingerprint == oldfp,
212 "fingerprint cannot change");
213 assert(((new_fingerprint >> 32) != 0x80000000) && (int)new_fingerprint !=0,
214 "fingerprint should call init to set initial value");
215 return new_fingerprint;
216 }
218 // name
219 int name_index() const { return _name_index; }
220 void set_name_index(int index) { _name_index = index; }
222 // signature
223 int signature_index() const { return _signature_index; }
224 void set_signature_index(int index) { _signature_index = index; }
226 // generics support
227 int generic_signature_index() const { return _generic_signature_index; }
228 void set_generic_signature_index(int index) { _generic_signature_index = index; }
230 // Sizing
231 static int header_size() {
232 return sizeof(constMethodOopDesc)/HeapWordSize;
233 }
235 // Object size needed
236 static int object_size(int code_size, int compressed_line_number_size,
237 int local_variable_table_length,
238 int checked_exceptions_length);
240 int object_size() const { return _constMethod_size; }
241 void set_constMethod_size(int size) { _constMethod_size = size; }
242 // Is object parsable by gc
243 bool object_is_parsable() { return object_size() > 0; }
245 // code size
246 int code_size() const { return _code_size; }
247 void set_code_size(int size) {
248 assert(max_method_code_size < (1 << 16),
249 "u2 is too small to hold method code size in general");
250 assert(0 <= size && size <= max_method_code_size, "invalid code size");
251 _code_size = size;
252 }
254 // linenumber table - note that length is unknown until decompression,
255 // see class CompressedLineNumberReadStream.
256 u_char* compressed_linenumber_table() const; // not preserved by gc
257 u2* checked_exceptions_length_addr() const;
258 u2* localvariable_table_length_addr() const;
260 // checked exceptions
261 int checked_exceptions_length() const;
262 CheckedExceptionElement* checked_exceptions_start() const;
264 // localvariable table
265 int localvariable_table_length() const;
266 LocalVariableTableElement* localvariable_table_start() const;
268 // byte codes
269 void set_code(address code) {
270 if (code_size() > 0) {
271 memcpy(code_base(), code, code_size());
272 }
273 }
274 address code_base() const { return (address) (this+1); }
275 address code_end() const { return code_base() + code_size(); }
276 bool contains(address bcp) const { return code_base() <= bcp
277 && bcp < code_end(); }
278 // Offset to bytecodes
279 static ByteSize codes_offset()
280 { return in_ByteSize(sizeof(constMethodOopDesc)); }
282 // interpreter support
283 static ByteSize constants_offset()
284 { return byte_offset_of(constMethodOopDesc, _constants); }
285 static ByteSize exception_table_offset()
286 { return byte_offset_of(constMethodOopDesc, _exception_table); }
288 // Garbage collection support
289 oop* adr_constants() const { return (oop*)&_constants; }
290 oop* adr_stackmap_data() const { return (oop*)&_stackmap_data; }
291 oop* adr_exception_table() const { return (oop*)&_exception_table; }
292 bool is_conc_safe() { return _is_conc_safe; }
293 void set_is_conc_safe(bool v) { _is_conc_safe = v; }
295 // Unique id for the method
296 static const u2 MAX_IDNUM;
297 static const u2 UNSET_IDNUM;
298 u2 method_idnum() const { return _method_idnum; }
299 void set_method_idnum(u2 idnum) { _method_idnum = idnum; }
301 private:
302 // Since the size of the compressed line number table is unknown, the
303 // offsets of the other variable sized sections are computed backwards
304 // from the end of the constMethodOop.
306 // First byte after constMethodOop
307 address constMethod_end() const
308 { return (address)((oop*)this + _constMethod_size); }
310 // Last short in constMethodOop
311 u2* last_u2_element() const
312 { return (u2*)constMethod_end() - 1; }
313 };
315 #endif // SHARE_VM_OOPS_CONSTMETHODOOP_HPP