Mercurial > hg > truffle
annotate src/share/vm/interpreter/oopMapCache.hpp @ 3109:3664989976e2
Merge
author | Gilles Duboscq <gilles.duboscq@oracle.com> |
---|---|
date | Fri, 01 Jul 2011 12:57:10 +0200 |
parents | c760f78e0a53 |
children | d2a62e0f25eb |
rev | line source |
---|---|
0 | 1 /* |
1972 | 2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #ifndef SHARE_VM_INTERPRETER_OOPMAPCACHE_HPP |
26 #define SHARE_VM_INTERPRETER_OOPMAPCACHE_HPP | |
27 | |
28 #include "oops/generateOopMap.hpp" | |
1983
c760f78e0a53
7003125: precompiled.hpp is included when precompiled headers are not used
stefank
parents:
1972
diff
changeset
|
29 #include "runtime/mutex.hpp" |
1972 | 30 |
0 | 31 // A Cache for storing (method, bci) -> oopMap. |
32 // The memory management system uses the cache when locating object | |
33 // references in an interpreted frame. | |
34 // | |
35 // OopMapCache's are allocated lazily per instanceKlass. | |
36 | |
37 // The oopMap (InterpreterOopMap) is stored as a bit mask. If the | |
38 // bit_mask can fit into two words it is stored in | |
39 // the _bit_mask array, otherwise it is allocated on the heap. | |
40 // For OopMapCacheEntry the bit_mask is allocated in the C heap | |
41 // because these entries persist between garbage collections. | |
42 // For InterpreterOopMap the bit_mask is allocated in | |
43 // a resource area for better performance. InterpreterOopMap | |
44 // should only be created and deleted during same garbage collection. | |
45 // | |
46 // If ENABBLE_ZAP_DEAD_LOCALS is defined, two bits are used | |
47 // per entry instead of one. In all cases, | |
48 // the first bit is set to indicate oops as opposed to other | |
49 // values. If the second bit is available, | |
50 // it is set for dead values. We get the following encoding: | |
51 // | |
52 // 00 live value | |
53 // 01 live oop | |
54 // 10 dead value | |
55 // 11 <unused> (we cannot distinguish between dead oops or values with the current oop map generator) | |
56 | |
57 | |
58 class OffsetClosure { | |
59 public: | |
60 virtual void offset_do(int offset) = 0; | |
61 }; | |
62 | |
63 | |
64 class InterpreterOopMap: ResourceObj { | |
65 friend class OopMapCache; | |
66 | |
67 public: | |
68 enum { | |
69 N = 2, // the number of words reserved | |
70 // for inlined mask storage | |
71 small_mask_limit = N * BitsPerWord, // the maximum number of bits | |
72 // available for small masks, | |
73 // small_mask_limit can be set to 0 | |
74 // for testing bit_mask allocation | |
75 | |
76 #ifdef ENABLE_ZAP_DEAD_LOCALS | |
77 bits_per_entry = 2, | |
78 dead_bit_number = 1, | |
79 #else | |
80 bits_per_entry = 1, | |
81 #endif | |
82 oop_bit_number = 0 | |
83 }; | |
84 | |
85 private: | |
86 methodOop _method; // the method for which the mask is valid | |
87 unsigned short _bci; // the bci for which the mask is valid | |
88 int _mask_size; // the mask size in bits | |
89 int _expression_stack_size; // the size of the expression stack in slots | |
90 | |
91 protected: | |
92 intptr_t _bit_mask[N]; // the bit mask if | |
93 // mask_size <= small_mask_limit, | |
94 // ptr to bit mask otherwise | |
95 // "protected" so that sub classes can | |
96 // access it without using trickery in | |
97 // methd bit_mask(). | |
98 #ifdef ASSERT | |
99 bool _resource_allocate_bit_mask; | |
100 #endif | |
101 | |
102 // access methods | |
103 methodOop method() const { return _method; } | |
104 void set_method(methodOop v) { _method = v; } | |
105 int bci() const { return _bci; } | |
106 void set_bci(int v) { _bci = v; } | |
107 int mask_size() const { return _mask_size; } | |
108 void set_mask_size(int v) { _mask_size = v; } | |
109 int number_of_entries() const { return mask_size() / bits_per_entry; } | |
110 // Test bit mask size and return either the in-line bit mask or allocated | |
111 // bit mask. | |
112 uintptr_t* bit_mask() { return (uintptr_t*)(mask_size() <= small_mask_limit ? (intptr_t)_bit_mask : _bit_mask[0]); } | |
113 | |
114 // return the word size of_bit_mask. mask_size() <= 4 * MAX_USHORT | |
115 size_t mask_word_size() { | |
116 return (mask_size() + BitsPerWord - 1) / BitsPerWord; | |
117 } | |
118 | |
119 uintptr_t entry_at(int offset) { int i = offset * bits_per_entry; return bit_mask()[i / BitsPerWord] >> (i % BitsPerWord); } | |
120 | |
121 void set_expression_stack_size(int sz) { _expression_stack_size = sz; } | |
122 | |
123 #ifdef ENABLE_ZAP_DEAD_LOCALS | |
124 bool is_dead(int offset) { return (entry_at(offset) & (1 << dead_bit_number)) != 0; } | |
125 #endif | |
126 | |
127 // Lookup | |
128 bool match(methodHandle method, int bci) { return _method == method() && _bci == bci; } | |
129 bool is_empty(); | |
130 | |
131 // Initialization | |
132 void initialize(); | |
133 | |
134 public: | |
135 InterpreterOopMap(); | |
136 ~InterpreterOopMap(); | |
137 | |
138 // Copy the OopMapCacheEntry in parameter "from" into this | |
139 // InterpreterOopMap. If the _bit_mask[0] in "from" points to | |
140 // allocated space (i.e., the bit mask was to large to hold | |
141 // in-line), allocate the space from a Resource area. | |
142 void resource_copy(OopMapCacheEntry* from); | |
143 | |
144 void iterate_oop(OffsetClosure* oop_closure); | |
145 void oop_iterate(OopClosure * blk); | |
146 void oop_iterate(OopClosure * blk, MemRegion mr); | |
147 void verify(); | |
148 void print(); | |
149 | |
150 bool is_oop (int offset) { return (entry_at(offset) & (1 << oop_bit_number )) != 0; } | |
151 | |
152 int expression_stack_size() { return _expression_stack_size; } | |
153 | |
154 #ifdef ENABLE_ZAP_DEAD_LOCALS | |
155 void iterate_all(OffsetClosure* oop_closure, OffsetClosure* value_closure, OffsetClosure* dead_closure); | |
156 #endif | |
157 }; | |
158 | |
159 class OopMapCache : public CHeapObj { | |
160 private: | |
161 enum { _size = 32, // Use fixed size for now | |
162 _probe_depth = 3 // probe depth in case of collisions | |
163 }; | |
164 | |
165 OopMapCacheEntry* _array; | |
166 | |
167 unsigned int hash_value_for(methodHandle method, int bci); | |
168 OopMapCacheEntry* entry_at(int i) const; | |
169 | |
170 Mutex _mut; | |
171 | |
172 void flush(); | |
173 | |
174 public: | |
175 OopMapCache(); | |
176 ~OopMapCache(); // free up memory | |
177 | |
178 // flush cache entry is occupied by an obsolete method | |
179 void flush_obsolete_entries(); | |
180 | |
181 // Returns the oopMap for (method, bci) in parameter "entry". | |
182 // Returns false if an oop map was not found. | |
183 void lookup(methodHandle method, int bci, InterpreterOopMap* entry); | |
184 | |
185 // Compute an oop map without updating the cache or grabbing any locks (for debugging) | |
186 static void compute_one_oop_map(methodHandle method, int bci, InterpreterOopMap* entry); | |
187 | |
188 // Helpers | |
189 // Iterate over the entries in the cached OopMapCacheEntry's | |
190 void oop_iterate(OopClosure *blk); | |
191 void oop_iterate(OopClosure *blk, MemRegion mr); | |
192 void verify(); | |
193 | |
194 // Returns total no. of bytes allocated as part of OopMapCache's | |
195 static long memory_usage() PRODUCT_RETURN0; | |
196 }; | |
1972 | 197 |
198 #endif // SHARE_VM_INTERPRETER_OOPMAPCACHE_HPP |