src/share/vm/interpreter/oopMapCache.cpp

Sat, 01 Sep 2012 13:25:18 -0400

author
coleenp
date
Sat, 01 Sep 2012 13:25:18 -0400
changeset 4037
da91efe96a93
parent 3900
d2a62e0f25eb
child 6680
78bbf4d43a14
permissions
-rw-r--r--

6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>

duke@435 1 /*
coleenp@4037 2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. 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 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #include "precompiled.hpp"
stefank@2314 26 #include "interpreter/oopMapCache.hpp"
stefank@2314 27 #include "memory/allocation.inline.hpp"
stefank@2314 28 #include "memory/resourceArea.hpp"
stefank@2314 29 #include "oops/oop.inline.hpp"
stefank@2314 30 #include "prims/jvmtiRedefineClassesTrace.hpp"
stefank@2314 31 #include "runtime/handles.inline.hpp"
stefank@2314 32 #include "runtime/signature.hpp"
duke@435 33
duke@435 34 class OopMapCacheEntry: private InterpreterOopMap {
duke@435 35 friend class InterpreterOopMap;
duke@435 36 friend class OopMapForCacheEntry;
duke@435 37 friend class OopMapCache;
duke@435 38 friend class VerifyClosure;
duke@435 39
duke@435 40 protected:
duke@435 41 // Initialization
duke@435 42 void fill(methodHandle method, int bci);
duke@435 43 // fills the bit mask for native calls
duke@435 44 void fill_for_native(methodHandle method);
duke@435 45 void set_mask(CellTypeState* vars, CellTypeState* stack, int stack_top);
duke@435 46
duke@435 47 // Deallocate bit masks and initialize fields
duke@435 48 void flush();
duke@435 49
duke@435 50 private:
duke@435 51 void allocate_bit_mask(); // allocates the bit mask on C heap f necessary
duke@435 52 void deallocate_bit_mask(); // allocates the bit mask on C heap f necessary
duke@435 53 bool verify_mask(CellTypeState *vars, CellTypeState *stack, int max_locals, int stack_top);
duke@435 54
duke@435 55 public:
duke@435 56 OopMapCacheEntry() : InterpreterOopMap() {
duke@435 57 #ifdef ASSERT
duke@435 58 _resource_allocate_bit_mask = false;
duke@435 59 #endif
duke@435 60 }
duke@435 61 };
duke@435 62
duke@435 63
duke@435 64 // Implementation of OopMapForCacheEntry
duke@435 65 // (subclass of GenerateOopMap, initializes an OopMapCacheEntry for a given method and bci)
duke@435 66
duke@435 67 class OopMapForCacheEntry: public GenerateOopMap {
duke@435 68 OopMapCacheEntry *_entry;
duke@435 69 int _bci;
duke@435 70 int _stack_top;
duke@435 71
duke@435 72 virtual bool report_results() const { return false; }
duke@435 73 virtual bool possible_gc_point (BytecodeStream *bcs);
duke@435 74 virtual void fill_stackmap_prolog (int nof_gc_points);
duke@435 75 virtual void fill_stackmap_epilog ();
duke@435 76 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
duke@435 77 CellTypeState* vars,
duke@435 78 CellTypeState* stack,
duke@435 79 int stack_top);
duke@435 80 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars);
duke@435 81
duke@435 82 public:
duke@435 83 OopMapForCacheEntry(methodHandle method, int bci, OopMapCacheEntry *entry);
duke@435 84
duke@435 85 // Computes stack map for (method,bci) and initialize entry
duke@435 86 void compute_map(TRAPS);
duke@435 87 int size();
duke@435 88 };
duke@435 89
duke@435 90
duke@435 91 OopMapForCacheEntry::OopMapForCacheEntry(methodHandle method, int bci, OopMapCacheEntry* entry) : GenerateOopMap(method) {
duke@435 92 _bci = bci;
duke@435 93 _entry = entry;
duke@435 94 _stack_top = -1;
duke@435 95 }
duke@435 96
duke@435 97
duke@435 98 void OopMapForCacheEntry::compute_map(TRAPS) {
duke@435 99 assert(!method()->is_native(), "cannot compute oop map for native methods");
duke@435 100 // First check if it is a method where the stackmap is always empty
duke@435 101 if (method()->code_size() == 0 || method()->max_locals() + method()->max_stack() == 0) {
duke@435 102 _entry->set_mask_size(0);
duke@435 103 } else {
duke@435 104 ResourceMark rm;
duke@435 105 GenerateOopMap::compute_map(CATCH);
duke@435 106 result_for_basicblock(_bci);
duke@435 107 }
duke@435 108 }
duke@435 109
duke@435 110
duke@435 111 bool OopMapForCacheEntry::possible_gc_point(BytecodeStream *bcs) {
duke@435 112 return false; // We are not reporting any result. We call result_for_basicblock directly
duke@435 113 }
duke@435 114
duke@435 115
duke@435 116 void OopMapForCacheEntry::fill_stackmap_prolog(int nof_gc_points) {
duke@435 117 // Do nothing
duke@435 118 }
duke@435 119
duke@435 120
duke@435 121 void OopMapForCacheEntry::fill_stackmap_epilog() {
duke@435 122 // Do nothing
duke@435 123 }
duke@435 124
duke@435 125
duke@435 126 void OopMapForCacheEntry::fill_init_vars(GrowableArray<intptr_t> *init_vars) {
duke@435 127 // Do nothing
duke@435 128 }
duke@435 129
duke@435 130
duke@435 131 void OopMapForCacheEntry::fill_stackmap_for_opcodes(BytecodeStream *bcs,
duke@435 132 CellTypeState* vars,
duke@435 133 CellTypeState* stack,
duke@435 134 int stack_top) {
duke@435 135 // Only interested in one specific bci
duke@435 136 if (bcs->bci() == _bci) {
duke@435 137 _entry->set_mask(vars, stack, stack_top);
duke@435 138 _stack_top = stack_top;
duke@435 139 }
duke@435 140 }
duke@435 141
duke@435 142
duke@435 143 int OopMapForCacheEntry::size() {
duke@435 144 assert(_stack_top != -1, "compute_map must be called first");
duke@435 145 return ((method()->is_static()) ? 0 : 1) + method()->max_locals() + _stack_top;
duke@435 146 }
duke@435 147
duke@435 148
duke@435 149 // Implementation of InterpreterOopMap and OopMapCacheEntry
duke@435 150
duke@435 151 class VerifyClosure : public OffsetClosure {
duke@435 152 private:
duke@435 153 OopMapCacheEntry* _entry;
duke@435 154 bool _failed;
duke@435 155
duke@435 156 public:
duke@435 157 VerifyClosure(OopMapCacheEntry* entry) { _entry = entry; _failed = false; }
duke@435 158 void offset_do(int offset) { if (!_entry->is_oop(offset)) _failed = true; }
duke@435 159 bool failed() const { return _failed; }
duke@435 160 };
duke@435 161
duke@435 162 InterpreterOopMap::InterpreterOopMap() {
duke@435 163 initialize();
duke@435 164 #ifdef ASSERT
duke@435 165 _resource_allocate_bit_mask = true;
duke@435 166 #endif
duke@435 167 }
duke@435 168
duke@435 169 InterpreterOopMap::~InterpreterOopMap() {
duke@435 170 // The expection is that the bit mask was allocated
duke@435 171 // last in this resource area. That would make the free of the
duke@435 172 // bit_mask effective (see how FREE_RESOURCE_ARRAY does a free).
duke@435 173 // If it was not allocated last, there is not a correctness problem
duke@435 174 // but the space for the bit_mask is not freed.
duke@435 175 assert(_resource_allocate_bit_mask, "Trying to free C heap space");
duke@435 176 if (mask_size() > small_mask_limit) {
duke@435 177 FREE_RESOURCE_ARRAY(uintptr_t, _bit_mask[0], mask_word_size());
duke@435 178 }
duke@435 179 }
duke@435 180
duke@435 181 bool InterpreterOopMap::is_empty() {
duke@435 182 bool result = _method == NULL;
duke@435 183 assert(_method != NULL || (_bci == 0 &&
duke@435 184 (_mask_size == 0 || _mask_size == USHRT_MAX) &&
duke@435 185 _bit_mask[0] == 0), "Should be completely empty");
duke@435 186 return result;
duke@435 187 }
duke@435 188
duke@435 189 void InterpreterOopMap::initialize() {
duke@435 190 _method = NULL;
duke@435 191 _mask_size = USHRT_MAX; // This value should cause a failure quickly
duke@435 192 _bci = 0;
duke@435 193 _expression_stack_size = 0;
duke@435 194 for (int i = 0; i < N; i++) _bit_mask[i] = 0;
duke@435 195 }
duke@435 196
duke@435 197 void InterpreterOopMap::iterate_oop(OffsetClosure* oop_closure) {
duke@435 198 int n = number_of_entries();
duke@435 199 int word_index = 0;
duke@435 200 uintptr_t value = 0;
duke@435 201 uintptr_t mask = 0;
duke@435 202 // iterate over entries
duke@435 203 for (int i = 0; i < n; i++, mask <<= bits_per_entry) {
duke@435 204 // get current word
duke@435 205 if (mask == 0) {
duke@435 206 value = bit_mask()[word_index++];
duke@435 207 mask = 1;
duke@435 208 }
duke@435 209 // test for oop
duke@435 210 if ((value & (mask << oop_bit_number)) != 0) oop_closure->offset_do(i);
duke@435 211 }
duke@435 212 }
duke@435 213
duke@435 214
duke@435 215 #ifdef ENABLE_ZAP_DEAD_LOCALS
duke@435 216
duke@435 217 void InterpreterOopMap::iterate_all(OffsetClosure* oop_closure, OffsetClosure* value_closure, OffsetClosure* dead_closure) {
duke@435 218 int n = number_of_entries();
duke@435 219 int word_index = 0;
duke@435 220 uintptr_t value = 0;
duke@435 221 uintptr_t mask = 0;
duke@435 222 // iterate over entries
duke@435 223 for (int i = 0; i < n; i++, mask <<= bits_per_entry) {
duke@435 224 // get current word
duke@435 225 if (mask == 0) {
duke@435 226 value = bit_mask()[word_index++];
duke@435 227 mask = 1;
duke@435 228 }
duke@435 229 // test for dead values & oops, and for live values
duke@435 230 if ((value & (mask << dead_bit_number)) != 0) dead_closure->offset_do(i); // call this for all dead values or oops
duke@435 231 else if ((value & (mask << oop_bit_number)) != 0) oop_closure->offset_do(i); // call this for all live oops
duke@435 232 else value_closure->offset_do(i); // call this for all live values
duke@435 233 }
duke@435 234 }
duke@435 235
duke@435 236 #endif
duke@435 237
duke@435 238
duke@435 239 void InterpreterOopMap::print() {
duke@435 240 int n = number_of_entries();
duke@435 241 tty->print("oop map for ");
duke@435 242 method()->print_value();
duke@435 243 tty->print(" @ %d = [%d] { ", bci(), n);
duke@435 244 for (int i = 0; i < n; i++) {
duke@435 245 #ifdef ENABLE_ZAP_DEAD_LOCALS
duke@435 246 if (is_dead(i)) tty->print("%d+ ", i);
duke@435 247 else
duke@435 248 #endif
duke@435 249 if (is_oop(i)) tty->print("%d ", i);
duke@435 250 }
duke@435 251 tty->print_cr("}");
duke@435 252 }
duke@435 253
duke@435 254 class MaskFillerForNative: public NativeSignatureIterator {
duke@435 255 private:
duke@435 256 uintptr_t * _mask; // the bit mask to be filled
duke@435 257 int _size; // the mask size in bits
duke@435 258
duke@435 259 void set_one(int i) {
duke@435 260 i *= InterpreterOopMap::bits_per_entry;
duke@435 261 assert(0 <= i && i < _size, "offset out of bounds");
duke@435 262 _mask[i / BitsPerWord] |= (((uintptr_t) 1 << InterpreterOopMap::oop_bit_number) << (i % BitsPerWord));
duke@435 263 }
duke@435 264
duke@435 265 public:
duke@435 266 void pass_int() { /* ignore */ }
duke@435 267 void pass_long() { /* ignore */ }
duke@435 268 void pass_float() { /* ignore */ }
duke@435 269 void pass_double() { /* ignore */ }
duke@435 270 void pass_object() { set_one(offset()); }
duke@435 271
duke@435 272 MaskFillerForNative(methodHandle method, uintptr_t* mask, int size) : NativeSignatureIterator(method) {
duke@435 273 _mask = mask;
duke@435 274 _size = size;
duke@435 275 // initialize with 0
duke@435 276 int i = (size + BitsPerWord - 1) / BitsPerWord;
duke@435 277 while (i-- > 0) _mask[i] = 0;
duke@435 278 }
duke@435 279
duke@435 280 void generate() {
duke@435 281 NativeSignatureIterator::iterate();
duke@435 282 }
duke@435 283 };
duke@435 284
duke@435 285 bool OopMapCacheEntry::verify_mask(CellTypeState* vars, CellTypeState* stack, int max_locals, int stack_top) {
duke@435 286 // Check mask includes map
duke@435 287 VerifyClosure blk(this);
duke@435 288 iterate_oop(&blk);
duke@435 289 if (blk.failed()) return false;
duke@435 290
duke@435 291 // Check if map is generated correctly
duke@435 292 // (Use ?: operator to make sure all 'true' & 'false' are represented exactly the same so we can use == afterwards)
duke@435 293 if (TraceOopMapGeneration && Verbose) tty->print("Locals (%d): ", max_locals);
duke@435 294
duke@435 295 for(int i = 0; i < max_locals; i++) {
duke@435 296 bool v1 = is_oop(i) ? true : false;
duke@435 297 bool v2 = vars[i].is_reference() ? true : false;
duke@435 298 assert(v1 == v2, "locals oop mask generation error");
duke@435 299 if (TraceOopMapGeneration && Verbose) tty->print("%d", v1 ? 1 : 0);
duke@435 300 #ifdef ENABLE_ZAP_DEAD_LOCALS
duke@435 301 bool v3 = is_dead(i) ? true : false;
duke@435 302 bool v4 = !vars[i].is_live() ? true : false;
duke@435 303 assert(v3 == v4, "locals live mask generation error");
duke@435 304 assert(!(v1 && v3), "dead value marked as oop");
duke@435 305 #endif
duke@435 306 }
duke@435 307
duke@435 308 if (TraceOopMapGeneration && Verbose) { tty->cr(); tty->print("Stack (%d): ", stack_top); }
duke@435 309 for(int j = 0; j < stack_top; j++) {
duke@435 310 bool v1 = is_oop(max_locals + j) ? true : false;
duke@435 311 bool v2 = stack[j].is_reference() ? true : false;
duke@435 312 assert(v1 == v2, "stack oop mask generation error");
duke@435 313 if (TraceOopMapGeneration && Verbose) tty->print("%d", v1 ? 1 : 0);
duke@435 314 #ifdef ENABLE_ZAP_DEAD_LOCALS
duke@435 315 bool v3 = is_dead(max_locals + j) ? true : false;
duke@435 316 bool v4 = !stack[j].is_live() ? true : false;
duke@435 317 assert(v3 == v4, "stack live mask generation error");
duke@435 318 assert(!(v1 && v3), "dead value marked as oop");
duke@435 319 #endif
duke@435 320 }
duke@435 321 if (TraceOopMapGeneration && Verbose) tty->cr();
duke@435 322 return true;
duke@435 323 }
duke@435 324
duke@435 325 void OopMapCacheEntry::allocate_bit_mask() {
duke@435 326 if (mask_size() > small_mask_limit) {
duke@435 327 assert(_bit_mask[0] == 0, "bit mask should be new or just flushed");
duke@435 328 _bit_mask[0] = (intptr_t)
zgu@3900 329 NEW_C_HEAP_ARRAY(uintptr_t, mask_word_size(), mtClass);
duke@435 330 }
duke@435 331 }
duke@435 332
duke@435 333 void OopMapCacheEntry::deallocate_bit_mask() {
duke@435 334 if (mask_size() > small_mask_limit && _bit_mask[0] != 0) {
duke@435 335 assert(!Thread::current()->resource_area()->contains((void*)_bit_mask[0]),
duke@435 336 "This bit mask should not be in the resource area");
zgu@3900 337 FREE_C_HEAP_ARRAY(uintptr_t, _bit_mask[0], mtClass);
duke@435 338 debug_only(_bit_mask[0] = 0;)
duke@435 339 }
duke@435 340 }
duke@435 341
duke@435 342
duke@435 343 void OopMapCacheEntry::fill_for_native(methodHandle mh) {
duke@435 344 assert(mh->is_native(), "method must be native method");
duke@435 345 set_mask_size(mh->size_of_parameters() * bits_per_entry);
duke@435 346 allocate_bit_mask();
duke@435 347 // fill mask for parameters
duke@435 348 MaskFillerForNative mf(mh, bit_mask(), mask_size());
duke@435 349 mf.generate();
duke@435 350 }
duke@435 351
duke@435 352
duke@435 353 void OopMapCacheEntry::fill(methodHandle method, int bci) {
duke@435 354 HandleMark hm;
duke@435 355 // Flush entry to deallocate an existing entry
duke@435 356 flush();
duke@435 357 set_method(method());
duke@435 358 set_bci(bci);
duke@435 359 if (method->is_native()) {
duke@435 360 // Native method activations have oops only among the parameters and one
duke@435 361 // extra oop following the parameters (the mirror for static native methods).
duke@435 362 fill_for_native(method);
duke@435 363 } else {
duke@435 364 EXCEPTION_MARK;
duke@435 365 OopMapForCacheEntry gen(method, bci, this);
duke@435 366 gen.compute_map(CATCH);
duke@435 367 }
duke@435 368 }
duke@435 369
duke@435 370
duke@435 371 void OopMapCacheEntry::set_mask(CellTypeState *vars, CellTypeState *stack, int stack_top) {
duke@435 372 // compute bit mask size
duke@435 373 int max_locals = method()->max_locals();
duke@435 374 int n_entries = max_locals + stack_top;
duke@435 375 set_mask_size(n_entries * bits_per_entry);
duke@435 376 allocate_bit_mask();
duke@435 377 set_expression_stack_size(stack_top);
duke@435 378
duke@435 379 // compute bits
duke@435 380 int word_index = 0;
duke@435 381 uintptr_t value = 0;
duke@435 382 uintptr_t mask = 1;
duke@435 383
duke@435 384 CellTypeState* cell = vars;
duke@435 385 for (int entry_index = 0; entry_index < n_entries; entry_index++, mask <<= bits_per_entry, cell++) {
duke@435 386 // store last word
duke@435 387 if (mask == 0) {
duke@435 388 bit_mask()[word_index++] = value;
duke@435 389 value = 0;
duke@435 390 mask = 1;
duke@435 391 }
duke@435 392
duke@435 393 // switch to stack when done with locals
duke@435 394 if (entry_index == max_locals) {
duke@435 395 cell = stack;
duke@435 396 }
duke@435 397
duke@435 398 // set oop bit
duke@435 399 if ( cell->is_reference()) {
duke@435 400 value |= (mask << oop_bit_number );
duke@435 401 }
duke@435 402
duke@435 403 #ifdef ENABLE_ZAP_DEAD_LOCALS
duke@435 404 // set dead bit
duke@435 405 if (!cell->is_live()) {
duke@435 406 value |= (mask << dead_bit_number);
duke@435 407 assert(!cell->is_reference(), "dead value marked as oop");
duke@435 408 }
duke@435 409 #endif
duke@435 410 }
duke@435 411
duke@435 412 // make sure last word is stored
duke@435 413 bit_mask()[word_index] = value;
duke@435 414
duke@435 415 // verify bit mask
duke@435 416 assert(verify_mask(vars, stack, max_locals, stack_top), "mask could not be verified");
duke@435 417
duke@435 418
duke@435 419 }
duke@435 420
duke@435 421 void OopMapCacheEntry::flush() {
duke@435 422 deallocate_bit_mask();
duke@435 423 initialize();
duke@435 424 }
duke@435 425
duke@435 426
duke@435 427 // Implementation of OopMapCache
duke@435 428
duke@435 429 #ifndef PRODUCT
duke@435 430
duke@435 431 static long _total_memory_usage = 0;
duke@435 432
duke@435 433 long OopMapCache::memory_usage() {
duke@435 434 return _total_memory_usage;
duke@435 435 }
duke@435 436
duke@435 437 #endif
duke@435 438
duke@435 439 void InterpreterOopMap::resource_copy(OopMapCacheEntry* from) {
duke@435 440 assert(_resource_allocate_bit_mask,
duke@435 441 "Should not resource allocate the _bit_mask");
duke@435 442
duke@435 443 set_method(from->method());
duke@435 444 set_bci(from->bci());
duke@435 445 set_mask_size(from->mask_size());
duke@435 446 set_expression_stack_size(from->expression_stack_size());
duke@435 447
duke@435 448 // Is the bit mask contained in the entry?
duke@435 449 if (from->mask_size() <= small_mask_limit) {
duke@435 450 memcpy((void *)_bit_mask, (void *)from->_bit_mask,
duke@435 451 mask_word_size() * BytesPerWord);
duke@435 452 } else {
duke@435 453 // The expectation is that this InterpreterOopMap is a recently created
duke@435 454 // and empty. It is used to get a copy of a cached entry.
duke@435 455 // If the bit mask has a value, it should be in the
duke@435 456 // resource area.
duke@435 457 assert(_bit_mask[0] == 0 ||
duke@435 458 Thread::current()->resource_area()->contains((void*)_bit_mask[0]),
duke@435 459 "The bit mask should have been allocated from a resource area");
duke@435 460 // Allocate the bit_mask from a Resource area for performance. Allocating
duke@435 461 // from the C heap as is done for OopMapCache has a significant
duke@435 462 // performance impact.
duke@435 463 _bit_mask[0] = (uintptr_t) NEW_RESOURCE_ARRAY(uintptr_t, mask_word_size());
duke@435 464 assert(_bit_mask[0] != 0, "bit mask was not allocated");
duke@435 465 memcpy((void*) _bit_mask[0], (void*) from->_bit_mask[0],
duke@435 466 mask_word_size() * BytesPerWord);
duke@435 467 }
duke@435 468 }
duke@435 469
duke@435 470 inline unsigned int OopMapCache::hash_value_for(methodHandle method, int bci) {
duke@435 471 // We use method->code_size() rather than method->identity_hash() below since
duke@435 472 // the mark may not be present if a pointer to the method is already reversed.
duke@435 473 return ((unsigned int) bci)
duke@435 474 ^ ((unsigned int) method->max_locals() << 2)
duke@435 475 ^ ((unsigned int) method->code_size() << 4)
duke@435 476 ^ ((unsigned int) method->size_of_parameters() << 6);
duke@435 477 }
duke@435 478
duke@435 479
duke@435 480 OopMapCache::OopMapCache() :
duke@435 481 _mut(Mutex::leaf, "An OopMapCache lock", true)
duke@435 482 {
zgu@3900 483 _array = NEW_C_HEAP_ARRAY(OopMapCacheEntry, _size, mtClass);
duke@435 484 // Cannot call flush for initialization, since flush
duke@435 485 // will check if memory should be deallocated
duke@435 486 for(int i = 0; i < _size; i++) _array[i].initialize();
duke@435 487 NOT_PRODUCT(_total_memory_usage += sizeof(OopMapCache) + (sizeof(OopMapCacheEntry) * _size);)
duke@435 488 }
duke@435 489
duke@435 490
duke@435 491 OopMapCache::~OopMapCache() {
duke@435 492 assert(_array != NULL, "sanity check");
duke@435 493 // Deallocate oop maps that are allocated out-of-line
duke@435 494 flush();
duke@435 495 // Deallocate array
duke@435 496 NOT_PRODUCT(_total_memory_usage -= sizeof(OopMapCache) + (sizeof(OopMapCacheEntry) * _size);)
zgu@3900 497 FREE_C_HEAP_ARRAY(OopMapCacheEntry, _array, mtClass);
duke@435 498 }
duke@435 499
duke@435 500 OopMapCacheEntry* OopMapCache::entry_at(int i) const {
duke@435 501 return &_array[i % _size];
duke@435 502 }
duke@435 503
duke@435 504 void OopMapCache::flush() {
duke@435 505 for (int i = 0; i < _size; i++) _array[i].flush();
duke@435 506 }
duke@435 507
duke@435 508 void OopMapCache::flush_obsolete_entries() {
duke@435 509 for (int i = 0; i < _size; i++)
duke@435 510 if (!_array[i].is_empty() && _array[i].method()->is_old()) {
duke@435 511 // Cache entry is occupied by an old redefined method and we don't want
duke@435 512 // to pin it down so flush the entry.
dcubed@483 513 RC_TRACE(0x08000000, ("flush: %s(%s): cached entry @%d",
dcubed@483 514 _array[i].method()->name()->as_C_string(),
dcubed@483 515 _array[i].method()->signature()->as_C_string(), i));
dcubed@483 516
duke@435 517 _array[i].flush();
duke@435 518 }
duke@435 519 }
duke@435 520
duke@435 521 void OopMapCache::lookup(methodHandle method,
duke@435 522 int bci,
duke@435 523 InterpreterOopMap* entry_for) {
duke@435 524 MutexLocker x(&_mut);
duke@435 525
duke@435 526 OopMapCacheEntry* entry = NULL;
duke@435 527 int probe = hash_value_for(method, bci);
duke@435 528
duke@435 529 // Search hashtable for match
duke@435 530 int i;
duke@435 531 for(i = 0; i < _probe_depth; i++) {
duke@435 532 entry = entry_at(probe + i);
duke@435 533 if (entry->match(method, bci)) {
duke@435 534 entry_for->resource_copy(entry);
duke@435 535 assert(!entry_for->is_empty(), "A non-empty oop map should be returned");
duke@435 536 return;
duke@435 537 }
duke@435 538 }
duke@435 539
duke@435 540 if (TraceOopMapGeneration) {
duke@435 541 static int count = 0;
duke@435 542 ResourceMark rm;
duke@435 543 tty->print("%d - Computing oopmap at bci %d for ", ++count, bci);
duke@435 544 method->print_value(); tty->cr();
duke@435 545 }
duke@435 546
duke@435 547 // Entry is not in hashtable.
duke@435 548 // Compute entry and return it
duke@435 549
dcubed@483 550 if (method->should_not_be_cached()) {
coleenp@4037 551 // It is either not safe or not a good idea to cache this Method*
dcubed@483 552 // at this time. We give the caller of lookup() a copy of the
dcubed@483 553 // interesting info via parameter entry_for, but we don't add it to
coleenp@4037 554 // the cache. See the gory details in Method*.cpp.
dcubed@483 555 compute_one_oop_map(method, bci, entry_for);
dcubed@483 556 return;
dcubed@483 557 }
dcubed@483 558
duke@435 559 // First search for an empty slot
duke@435 560 for(i = 0; i < _probe_depth; i++) {
duke@435 561 entry = entry_at(probe + i);
duke@435 562 if (entry->is_empty()) {
duke@435 563 entry->fill(method, bci);
duke@435 564 entry_for->resource_copy(entry);
duke@435 565 assert(!entry_for->is_empty(), "A non-empty oop map should be returned");
duke@435 566 return;
duke@435 567 }
duke@435 568 }
duke@435 569
duke@435 570 if (TraceOopMapGeneration) {
duke@435 571 ResourceMark rm;
duke@435 572 tty->print_cr("*** collision in oopmap cache - flushing item ***");
duke@435 573 }
duke@435 574
duke@435 575 // No empty slot (uncommon case). Use (some approximation of a) LRU algorithm
duke@435 576 //entry_at(probe + _probe_depth - 1)->flush();
duke@435 577 //for(i = _probe_depth - 1; i > 0; i--) {
duke@435 578 // // Coping entry[i] = entry[i-1];
duke@435 579 // OopMapCacheEntry *to = entry_at(probe + i);
duke@435 580 // OopMapCacheEntry *from = entry_at(probe + i - 1);
duke@435 581 // to->copy(from);
duke@435 582 // }
duke@435 583
duke@435 584 assert(method->is_method(), "gaga");
duke@435 585
duke@435 586 entry = entry_at(probe + 0);
duke@435 587 entry->fill(method, bci);
duke@435 588
duke@435 589 // Copy the newly cached entry to input parameter
duke@435 590 entry_for->resource_copy(entry);
duke@435 591
duke@435 592 if (TraceOopMapGeneration) {
duke@435 593 ResourceMark rm;
duke@435 594 tty->print("Done with ");
duke@435 595 method->print_value(); tty->cr();
duke@435 596 }
duke@435 597 assert(!entry_for->is_empty(), "A non-empty oop map should be returned");
duke@435 598
duke@435 599 return;
duke@435 600 }
duke@435 601
duke@435 602 void OopMapCache::compute_one_oop_map(methodHandle method, int bci, InterpreterOopMap* entry) {
duke@435 603 // Due to the invariants above it's tricky to allocate a temporary OopMapCacheEntry on the stack
zgu@3900 604 OopMapCacheEntry* tmp = NEW_C_HEAP_ARRAY(OopMapCacheEntry, 1, mtClass);
duke@435 605 tmp->initialize();
duke@435 606 tmp->fill(method, bci);
duke@435 607 entry->resource_copy(tmp);
zgu@3900 608 FREE_C_HEAP_ARRAY(OopMapCacheEntry, tmp, mtInternal);
duke@435 609 }

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