Fri, 05 Oct 2012 18:57:10 -0700
7177003: C1: LogCompilation support
Summary: add LogCompilation support in C1 - both client and tiered mode.
Reviewed-by: twisti, kvn
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.
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23 */
25 #include "precompiled.hpp"
26 #include "classfile/altHashing.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "memory/filemap.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "oops/oop.inline.hpp"
32 #include "runtime/safepoint.hpp"
33 #include "utilities/dtrace.hpp"
34 #include "utilities/hashtable.hpp"
35 #include "utilities/hashtable.inline.hpp"
38 // This is a generic hashtable, designed to be used for the symbol
39 // and string tables.
40 //
41 // It is implemented as an open hash table with a fixed number of buckets.
42 //
43 // %note:
44 // - HashtableEntrys are allocated in blocks to reduce the space overhead.
46 template <MEMFLAGS F> BasicHashtableEntry<F>* BasicHashtable<F>::new_entry(unsigned int hashValue) {
47 BasicHashtableEntry<F>* entry;
49 if (_free_list) {
50 entry = _free_list;
51 _free_list = _free_list->next();
52 } else {
53 if (_first_free_entry + _entry_size >= _end_block) {
54 int block_size = MIN2(512, MAX2((int)_table_size / 2, (int)_number_of_entries));
55 int len = _entry_size * block_size;
56 len = 1 << log2_intptr(len); // round down to power of 2
57 assert(len >= _entry_size, "");
58 _first_free_entry = NEW_C_HEAP_ARRAY2(char, len, F, CURRENT_PC);
59 _end_block = _first_free_entry + len;
60 }
61 entry = (BasicHashtableEntry<F>*)_first_free_entry;
62 _first_free_entry += _entry_size;
63 }
65 assert(_entry_size % HeapWordSize == 0, "");
66 entry->set_hash(hashValue);
67 return entry;
68 }
71 template <class T, MEMFLAGS F> HashtableEntry<T, F>* Hashtable<T, F>::new_entry(unsigned int hashValue, T obj) {
72 HashtableEntry<T, F>* entry;
74 entry = (HashtableEntry<T, F>*)BasicHashtable<F>::new_entry(hashValue);
75 entry->set_literal(obj);
76 return entry;
77 }
79 // Check to see if the hashtable is unbalanced. The caller set a flag to
80 // rehash at the next safepoint. If this bucket is 60 times greater than the
81 // expected average bucket length, it's an unbalanced hashtable.
82 // This is somewhat an arbitrary heuristic but if one bucket gets to
83 // rehash_count which is currently 100, there's probably something wrong.
85 template <MEMFLAGS F> bool BasicHashtable<F>::check_rehash_table(int count) {
86 assert(table_size() != 0, "underflow");
87 if (count > (((double)number_of_entries()/(double)table_size())*rehash_multiple)) {
88 // Set a flag for the next safepoint, which should be at some guaranteed
89 // safepoint interval.
90 return true;
91 }
92 return false;
93 }
95 template <class T, MEMFLAGS F> jint Hashtable<T, F>::_seed = 0;
97 // Create a new table and using alternate hash code, populate the new table
98 // with the existing elements. This can be used to change the hash code
99 // and could in the future change the size of the table.
101 template <class T, MEMFLAGS F> void Hashtable<T, F>::move_to(Hashtable<T, F>* new_table) {
103 // Initialize the global seed for hashing.
104 _seed = AltHashing::compute_seed();
105 assert(seed() != 0, "shouldn't be zero");
107 int saved_entry_count = this->number_of_entries();
109 // Iterate through the table and create a new entry for the new table
110 for (int i = 0; i < new_table->table_size(); ++i) {
111 for (HashtableEntry<T, F>* p = bucket(i); p != NULL; ) {
112 HashtableEntry<T, F>* next = p->next();
113 T string = p->literal();
114 // Use alternate hashing algorithm on the symbol in the first table
115 unsigned int hashValue = string->new_hash(seed());
116 // Get a new index relative to the new table (can also change size)
117 int index = new_table->hash_to_index(hashValue);
118 p->set_hash(hashValue);
119 // Keep the shared bit in the Hashtable entry to indicate that this entry
120 // can't be deleted. The shared bit is the LSB in the _next field so
121 // walking the hashtable past these entries requires
122 // BasicHashtableEntry::make_ptr() call.
123 bool keep_shared = p->is_shared();
124 this->unlink_entry(p);
125 new_table->add_entry(index, p);
126 if (keep_shared) {
127 p->set_shared();
128 }
129 p = next;
130 }
131 }
132 // give the new table the free list as well
133 new_table->copy_freelist(this);
134 assert(new_table->number_of_entries() == saved_entry_count, "lost entry on dictionary copy?");
136 // Destroy memory used by the buckets in the hashtable. The memory
137 // for the elements has been used in a new table and is not
138 // destroyed. The memory reuse will benefit resizing the SystemDictionary
139 // to avoid a memory allocation spike at safepoint.
140 BasicHashtable<F>::free_buckets();
141 }
143 template <MEMFLAGS F> void BasicHashtable<F>::free_buckets() {
144 if (NULL != _buckets) {
145 // Don't delete the buckets in the shared space. They aren't
146 // allocated by os::malloc
147 if (!UseSharedSpaces ||
148 !FileMapInfo::current_info()->is_in_shared_space(_buckets)) {
149 FREE_C_HEAP_ARRAY(HashtableBucket, _buckets, F);
150 }
151 _buckets = NULL;
152 }
153 }
156 // Reverse the order of elements in the hash buckets.
158 template <MEMFLAGS F> void BasicHashtable<F>::reverse() {
160 for (int i = 0; i < _table_size; ++i) {
161 BasicHashtableEntry<F>* new_list = NULL;
162 BasicHashtableEntry<F>* p = bucket(i);
163 while (p != NULL) {
164 BasicHashtableEntry<F>* next = p->next();
165 p->set_next(new_list);
166 new_list = p;
167 p = next;
168 }
169 *bucket_addr(i) = new_list;
170 }
171 }
174 // Copy the table to the shared space.
176 template <MEMFLAGS F> void BasicHashtable<F>::copy_table(char** top, char* end) {
178 // Dump the hash table entries.
180 intptr_t *plen = (intptr_t*)(*top);
181 *top += sizeof(*plen);
183 int i;
184 for (i = 0; i < _table_size; ++i) {
185 for (BasicHashtableEntry<F>** p = _buckets[i].entry_addr();
186 *p != NULL;
187 p = (*p)->next_addr()) {
188 if (*top + entry_size() > end) {
189 report_out_of_shared_space(SharedMiscData);
190 }
191 *p = (BasicHashtableEntry<F>*)memcpy(*top, *p, entry_size());
192 *top += entry_size();
193 }
194 }
195 *plen = (char*)(*top) - (char*)plen - sizeof(*plen);
197 // Set the shared bit.
199 for (i = 0; i < _table_size; ++i) {
200 for (BasicHashtableEntry<F>* p = bucket(i); p != NULL; p = p->next()) {
201 p->set_shared();
202 }
203 }
204 }
208 // Reverse the order of elements in the hash buckets.
210 template <class T, MEMFLAGS F> void Hashtable<T, F>::reverse(void* boundary) {
212 for (int i = 0; i < this->table_size(); ++i) {
213 HashtableEntry<T, F>* high_list = NULL;
214 HashtableEntry<T, F>* low_list = NULL;
215 HashtableEntry<T, F>* last_low_entry = NULL;
216 HashtableEntry<T, F>* p = bucket(i);
217 while (p != NULL) {
218 HashtableEntry<T, F>* next = p->next();
219 if ((void*)p->literal() >= boundary) {
220 p->set_next(high_list);
221 high_list = p;
222 } else {
223 p->set_next(low_list);
224 low_list = p;
225 if (last_low_entry == NULL) {
226 last_low_entry = p;
227 }
228 }
229 p = next;
230 }
231 if (low_list != NULL) {
232 *bucket_addr(i) = low_list;
233 last_low_entry->set_next(high_list);
234 } else {
235 *bucket_addr(i) = high_list;
236 }
237 }
238 }
241 // Dump the hash table buckets.
243 template <MEMFLAGS F> void BasicHashtable<F>::copy_buckets(char** top, char* end) {
244 intptr_t len = _table_size * sizeof(HashtableBucket<F>);
245 *(intptr_t*)(*top) = len;
246 *top += sizeof(intptr_t);
248 *(intptr_t*)(*top) = _number_of_entries;
249 *top += sizeof(intptr_t);
251 if (*top + len > end) {
252 report_out_of_shared_space(SharedMiscData);
253 }
254 _buckets = (HashtableBucket<F>*)memcpy(*top, _buckets, len);
255 *top += len;
256 }
259 #ifndef PRODUCT
261 template <class T, MEMFLAGS F> void Hashtable<T, F>::print() {
262 ResourceMark rm;
264 for (int i = 0; i < BasicHashtable<F>::table_size(); i++) {
265 HashtableEntry<T, F>* entry = bucket(i);
266 while(entry != NULL) {
267 tty->print("%d : ", i);
268 entry->literal()->print();
269 tty->cr();
270 entry = entry->next();
271 }
272 }
273 }
276 template <MEMFLAGS F> void BasicHashtable<F>::verify() {
277 int count = 0;
278 for (int i = 0; i < table_size(); i++) {
279 for (BasicHashtableEntry<F>* p = bucket(i); p != NULL; p = p->next()) {
280 ++count;
281 }
282 }
283 assert(count == number_of_entries(), "number of hashtable entries incorrect");
284 }
287 #endif // PRODUCT
290 #ifdef ASSERT
292 template <MEMFLAGS F> void BasicHashtable<F>::verify_lookup_length(double load) {
293 if ((double)_lookup_length / (double)_lookup_count > load * 2.0) {
294 warning("Performance bug: SystemDictionary lookup_count=%d "
295 "lookup_length=%d average=%lf load=%f",
296 _lookup_count, _lookup_length,
297 (double) _lookup_length / _lookup_count, load);
298 }
299 }
301 #endif
302 // Explicitly instantiate these types
303 template class Hashtable<ConstantPool*, mtClass>;
304 template class Hashtable<Symbol*, mtSymbol>;
305 template class Hashtable<Klass*, mtClass>;
306 template class Hashtable<oop, mtClass>;
307 #ifdef SOLARIS
308 template class Hashtable<oop, mtSymbol>;
309 #endif
310 template class Hashtable<oopDesc*, mtSymbol>;
311 template class Hashtable<Symbol*, mtClass>;
312 template class HashtableEntry<Symbol*, mtSymbol>;
313 template class HashtableEntry<Symbol*, mtClass>;
314 template class HashtableEntry<oop, mtSymbol>;
315 template class BasicHashtableEntry<mtSymbol>;
316 template class BasicHashtableEntry<mtCode>;
317 template class BasicHashtable<mtClass>;
318 template class BasicHashtable<mtSymbol>;
319 template class BasicHashtable<mtCode>;
320 template class BasicHashtable<mtInternal>;