1 /* 2 * Copyright (c) 2005, 2017, 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 */ 24 25 #include "precompiled.hpp" 26 #include "ci/bcEscapeAnalyzer.hpp" 27 #include "ci/ciConstant.hpp" 28 #include "ci/ciField.hpp" 29 #include "ci/ciMethodBlocks.hpp" 30 #include "ci/ciStreams.hpp" 31 #include "interpreter/bytecode.hpp" 32 #include "oops/oop.inline.hpp" 33 #include "utilities/bitMap.inline.hpp" 34 35 36 37 #ifndef PRODUCT 38 #define TRACE_BCEA(level, code) \ 39 if (EstimateArgEscape && BCEATraceLevel >= level) { \ 40 code; \ 41 } 42 #else 43 #define TRACE_BCEA(level, code) 44 #endif 45 46 // Maintain a map of which arguments a local variable or 47 // stack slot may contain. In addition to tracking 48 // arguments, it tracks two special values, "allocated" 49 // which represents any object allocated in the current 50 // method, and "unknown" which is any other object. 51 // Up to 30 arguments are handled, with the last one 52 // representing summary information for any extra arguments 53 class BCEscapeAnalyzer::ArgumentMap { 54 uint _bits; 55 enum {MAXBIT = 29, 56 ALLOCATED = 1, 57 UNKNOWN = 2}; 58 59 uint int_to_bit(uint e) const { 60 if (e > MAXBIT) 61 e = MAXBIT; 62 return (1 << (e + 2)); 63 } 64 65 public: 66 ArgumentMap() { _bits = 0;} 67 void set_bits(uint bits) { _bits = bits;} 68 uint get_bits() const { return _bits;} 69 void clear() { _bits = 0;} 70 void set_all() { _bits = ~0u; } 71 bool is_empty() const { return _bits == 0; } 72 bool contains(uint var) const { return (_bits & int_to_bit(var)) != 0; } 73 bool is_singleton(uint var) const { return (_bits == int_to_bit(var)); } 74 bool contains_unknown() const { return (_bits & UNKNOWN) != 0; } 75 bool contains_allocated() const { return (_bits & ALLOCATED) != 0; } 76 bool contains_vars() const { return (_bits & (((1 << MAXBIT) -1) << 2)) != 0; } 77 void set(uint var) { _bits = int_to_bit(var); } 78 void add(uint var) { _bits |= int_to_bit(var); } 79 void add_unknown() { _bits = UNKNOWN; } 80 void add_allocated() { _bits = ALLOCATED; } 81 void set_union(const ArgumentMap &am) { _bits |= am._bits; } 82 void set_intersect(const ArgumentMap &am) { _bits |= am._bits; } 83 void set_difference(const ArgumentMap &am) { _bits &= ~am._bits; } 84 void operator=(const ArgumentMap &am) { _bits = am._bits; } 85 bool operator==(const ArgumentMap &am) { return _bits == am._bits; } 86 bool operator!=(const ArgumentMap &am) { return _bits != am._bits; } 87 }; 88 89 class BCEscapeAnalyzer::StateInfo { 90 public: 91 ArgumentMap *_vars; 92 ArgumentMap *_stack; 93 int _stack_height; 94 int _max_stack; 95 bool _initialized; 96 ArgumentMap empty_map; 97 98 StateInfo() { 99 empty_map.clear(); 100 } 101 102 ArgumentMap raw_pop() { guarantee(_stack_height > 0, "stack underflow"); return _stack[--_stack_height]; } 103 ArgumentMap apop() { return raw_pop(); } 104 void spop() { raw_pop(); } 105 void lpop() { spop(); spop(); } 106 void raw_push(ArgumentMap i) { guarantee(_stack_height < _max_stack, "stack overflow"); _stack[_stack_height++] = i; } 107 void apush(ArgumentMap i) { raw_push(i); } 108 void spush() { raw_push(empty_map); } 109 void lpush() { spush(); spush(); } 110 111 }; 112 113 void BCEscapeAnalyzer::set_returned(ArgumentMap vars) { 114 for (int i = 0; i < _arg_size; i++) { 115 if (vars.contains(i)) 116 _arg_returned.set(i); 117 } 118 _return_local = _return_local && !(vars.contains_unknown() || vars.contains_allocated()); 119 _return_allocated = _return_allocated && vars.contains_allocated() && !(vars.contains_unknown() || vars.contains_vars()); 120 } 121 122 // return true if any element of vars is an argument 123 bool BCEscapeAnalyzer::is_argument(ArgumentMap vars) { 124 for (int i = 0; i < _arg_size; i++) { 125 if (vars.contains(i)) 126 return true; 127 } 128 return false; 129 } 130 131 // return true if any element of vars is an arg_stack argument 132 bool BCEscapeAnalyzer::is_arg_stack(ArgumentMap vars){ 133 if (_conservative) 134 return true; 135 for (int i = 0; i < _arg_size; i++) { 136 if (vars.contains(i) && _arg_stack.test(i)) 137 return true; 138 } 139 return false; 140 } 141 142 // return true if all argument elements of vars are returned 143 bool BCEscapeAnalyzer::returns_all(ArgumentMap vars) { 144 for (int i = 0; i < _arg_size; i++) { 145 if (vars.contains(i) && !_arg_returned.test(i)) { 146 return false; 147 } 148 } 149 return true; 150 } 151 152 void BCEscapeAnalyzer::clear_bits(ArgumentMap vars, VectorSet &bm) { 153 for (int i = 0; i < _arg_size; i++) { 154 if (vars.contains(i)) { 155 bm >>= i; 156 } 157 } 158 } 159 160 void BCEscapeAnalyzer::set_method_escape(ArgumentMap vars) { 161 clear_bits(vars, _arg_local); 162 if (vars.contains_allocated()) { 163 _allocated_escapes = true; 164 } 165 } 166 167 void BCEscapeAnalyzer::set_global_escape(ArgumentMap vars, bool merge) { 168 clear_bits(vars, _arg_local); 169 clear_bits(vars, _arg_stack); 170 if (vars.contains_allocated()) 171 _allocated_escapes = true; 172 173 if (merge && !vars.is_empty()) { 174 // Merge new state into already processed block. 175 // New state is not taken into account and 176 // it may invalidate set_returned() result. 177 if (vars.contains_unknown() || vars.contains_allocated()) { 178 _return_local = false; 179 } 180 if (vars.contains_unknown() || vars.contains_vars()) { 181 _return_allocated = false; 182 } 183 if (_return_local && vars.contains_vars() && !returns_all(vars)) { 184 // Return result should be invalidated if args in new 185 // state are not recorded in return state. 186 _return_local = false; 187 } 188 } 189 } 190 191 void BCEscapeAnalyzer::set_dirty(ArgumentMap vars) { 192 clear_bits(vars, _dirty); 193 } 194 195 void BCEscapeAnalyzer::set_modified(ArgumentMap vars, int offs, int size) { 196 197 for (int i = 0; i < _arg_size; i++) { 198 if (vars.contains(i)) { 199 set_arg_modified(i, offs, size); 200 } 201 } 202 if (vars.contains_unknown()) 203 _unknown_modified = true; 204 } 205 206 bool BCEscapeAnalyzer::is_recursive_call(ciMethod* callee) { 207 for (BCEscapeAnalyzer* scope = this; scope != NULL; scope = scope->_parent) { 208 if (scope->method() == callee) { 209 return true; 210 } 211 } 212 return false; 213 } 214 215 bool BCEscapeAnalyzer::is_arg_modified(int arg, int offset, int size_in_bytes) { 216 if (offset == OFFSET_ANY) 217 return _arg_modified[arg] != 0; 218 assert(arg >= 0 && arg < _arg_size, "must be an argument."); 219 bool modified = false; 220 int l = offset / HeapWordSize; 221 int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize; 222 if (l > ARG_OFFSET_MAX) 223 l = ARG_OFFSET_MAX; 224 if (h > ARG_OFFSET_MAX+1) 225 h = ARG_OFFSET_MAX + 1; 226 for (int i = l; i < h; i++) { 227 modified = modified || (_arg_modified[arg] & (1 << i)) != 0; 228 } 229 return modified; 230 } 231 232 void BCEscapeAnalyzer::set_arg_modified(int arg, int offset, int size_in_bytes) { 233 if (offset == OFFSET_ANY) { 234 _arg_modified[arg] = (uint) -1; 235 return; 236 } 237 assert(arg >= 0 && arg < _arg_size, "must be an argument."); 238 int l = offset / HeapWordSize; 239 int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize; 240 if (l > ARG_OFFSET_MAX) 241 l = ARG_OFFSET_MAX; 242 if (h > ARG_OFFSET_MAX+1) 243 h = ARG_OFFSET_MAX + 1; 244 for (int i = l; i < h; i++) { 245 _arg_modified[arg] |= (1 << i); 246 } 247 } 248 249 void BCEscapeAnalyzer::invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder) { 250 int i; 251 252 // retrieve information about the callee 253 ciInstanceKlass* klass = target->holder(); 254 ciInstanceKlass* calling_klass = method()->holder(); 255 ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder); 256 ciInstanceKlass* actual_recv = callee_holder; 257 258 // Some methods are obviously bindable without any type checks so 259 // convert them directly to an invokespecial or invokestatic. 260 if (target->is_loaded() && !target->is_abstract() && target->can_be_statically_bound()) { 261 switch (code) { 262 case Bytecodes::_invokevirtual: 263 code = Bytecodes::_invokespecial; 264 break; 265 case Bytecodes::_invokehandle: 266 code = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokespecial; 267 break; 268 default: 269 break; 270 } 271 } 272 273 // compute size of arguments 274 int arg_size = target->invoke_arg_size(code); 275 int arg_base = MAX2(state._stack_height - arg_size, 0); 276 277 // direct recursive calls are skipped if they can be bound statically without introducing 278 // dependencies and if parameters are passed at the same position as in the current method 279 // other calls are skipped if there are no unescaped arguments passed to them 280 bool directly_recursive = (method() == target) && 281 (code != Bytecodes::_invokevirtual || target->is_final_method() || state._stack[arg_base] .is_empty()); 282 283 // check if analysis of callee can safely be skipped 284 bool skip_callee = true; 285 for (i = state._stack_height - 1; i >= arg_base && skip_callee; i--) { 286 ArgumentMap arg = state._stack[i]; 287 skip_callee = !is_argument(arg) || !is_arg_stack(arg) || (directly_recursive && arg.is_singleton(i - arg_base)); 288 } 289 // For now we conservatively skip invokedynamic. 290 if (code == Bytecodes::_invokedynamic) { 291 skip_callee = true; 292 } 293 if (skip_callee) { 294 TRACE_BCEA(3, tty->print_cr("[EA] skipping method %s::%s", holder->name()->as_utf8(), target->name()->as_utf8())); 295 for (i = 0; i < arg_size; i++) { 296 set_method_escape(state.raw_pop()); 297 } 298 _unknown_modified = true; // assume the worst since we don't analyze the called method 299 return; 300 } 301 302 // determine actual method (use CHA if necessary) 303 ciMethod* inline_target = NULL; 304 if (target->is_loaded() && klass->is_loaded() 305 && (klass->is_initialized() || (klass->is_interface() && target->holder()->is_initialized())) 306 && target->is_loaded()) { 307 if (code == Bytecodes::_invokestatic 308 || code == Bytecodes::_invokespecial 309 || (code == Bytecodes::_invokevirtual && target->is_final_method())) { 310 inline_target = target; 311 } else { 312 inline_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv); 313 } 314 } 315 316 if (inline_target != NULL && !is_recursive_call(inline_target)) { 317 // analyze callee 318 BCEscapeAnalyzer analyzer(inline_target, this); 319 320 // adjust escape state of actual parameters 321 bool must_record_dependencies = false; 322 for (i = arg_size - 1; i >= 0; i--) { 323 ArgumentMap arg = state.raw_pop(); 324 // Check if callee arg is a caller arg or an allocated object 325 bool allocated = arg.contains_allocated(); 326 if (!(is_argument(arg) || allocated)) 327 continue; 328 for (int j = 0; j < _arg_size; j++) { 329 if (arg.contains(j)) { 330 _arg_modified[j] |= analyzer._arg_modified[i]; 331 } 332 } 333 if (!(is_arg_stack(arg) || allocated)) { 334 // arguments have already been recognized as escaping 335 } else if (analyzer.is_arg_stack(i) && !analyzer.is_arg_returned(i)) { 336 set_method_escape(arg); 337 must_record_dependencies = true; 338 } else { 339 set_global_escape(arg); 340 } 341 } 342 _unknown_modified = _unknown_modified || analyzer.has_non_arg_side_affects(); 343 344 // record dependencies if at least one parameter retained stack-allocatable 345 if (must_record_dependencies) { 346 if (code == Bytecodes::_invokeinterface || 347 (code == Bytecodes::_invokevirtual && !target->is_final_method())) { 348 _dependencies.append(actual_recv); 349 _dependencies.append(inline_target); 350 } 351 _dependencies.appendAll(analyzer.dependencies()); 352 } 353 } else { 354 TRACE_BCEA(1, tty->print_cr("[EA] virtual method %s is not monomorphic.", 355 target->name()->as_utf8())); 356 // conservatively mark all actual parameters as escaping globally 357 for (i = 0; i < arg_size; i++) { 358 ArgumentMap arg = state.raw_pop(); 359 if (!is_argument(arg)) 360 continue; 361 set_modified(arg, OFFSET_ANY, type2size[T_INT]*HeapWordSize); 362 set_global_escape(arg); 363 } 364 _unknown_modified = true; // assume the worst since we don't know the called method 365 } 366 } 367 368 bool BCEscapeAnalyzer::contains(uint arg_set1, uint arg_set2) { 369 return ((~arg_set1) | arg_set2) == 0; 370 } 371 372 373 void BCEscapeAnalyzer::iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors) { 374 375 blk->set_processed(); 376 ciBytecodeStream s(method()); 377 int limit_bci = blk->limit_bci(); 378 bool fall_through = false; 379 ArgumentMap allocated_obj; 380 allocated_obj.add_allocated(); 381 ArgumentMap unknown_obj; 382 unknown_obj.add_unknown(); 383 ArgumentMap empty_map; 384 385 s.reset_to_bci(blk->start_bci()); 386 while (s.next() != ciBytecodeStream::EOBC() && s.cur_bci() < limit_bci) { 387 fall_through = true; 388 switch (s.cur_bc()) { 389 case Bytecodes::_nop: 390 break; 391 case Bytecodes::_aconst_null: 392 state.apush(unknown_obj); 393 break; 394 case Bytecodes::_iconst_m1: 395 case Bytecodes::_iconst_0: 396 case Bytecodes::_iconst_1: 397 case Bytecodes::_iconst_2: 398 case Bytecodes::_iconst_3: 399 case Bytecodes::_iconst_4: 400 case Bytecodes::_iconst_5: 401 case Bytecodes::_fconst_0: 402 case Bytecodes::_fconst_1: 403 case Bytecodes::_fconst_2: 404 case Bytecodes::_bipush: 405 case Bytecodes::_sipush: 406 state.spush(); 407 break; 408 case Bytecodes::_lconst_0: 409 case Bytecodes::_lconst_1: 410 case Bytecodes::_dconst_0: 411 case Bytecodes::_dconst_1: 412 state.lpush(); 413 break; 414 case Bytecodes::_ldc: 415 case Bytecodes::_ldc_w: 416 case Bytecodes::_ldc2_w: 417 { 418 // Avoid calling get_constant() which will try to allocate 419 // unloaded constant. We need only constant's type. 420 int index = s.get_constant_pool_index(); 421 constantTag tag = s.get_constant_pool_tag(index); 422 if (tag.is_long() || tag.is_double()) { 423 // Only longs and doubles use 2 stack slots. 424 state.lpush(); 425 } else if (tag.basic_type() == T_OBJECT) { 426 state.apush(unknown_obj); 427 } else { 428 state.spush(); 429 } 430 break; 431 } 432 case Bytecodes::_aload: 433 state.apush(state._vars[s.get_index()]); 434 break; 435 case Bytecodes::_iload: 436 case Bytecodes::_fload: 437 case Bytecodes::_iload_0: 438 case Bytecodes::_iload_1: 439 case Bytecodes::_iload_2: 440 case Bytecodes::_iload_3: 441 case Bytecodes::_fload_0: 442 case Bytecodes::_fload_1: 443 case Bytecodes::_fload_2: 444 case Bytecodes::_fload_3: 445 state.spush(); 446 break; 447 case Bytecodes::_lload: 448 case Bytecodes::_dload: 449 case Bytecodes::_lload_0: 450 case Bytecodes::_lload_1: 451 case Bytecodes::_lload_2: 452 case Bytecodes::_lload_3: 453 case Bytecodes::_dload_0: 454 case Bytecodes::_dload_1: 455 case Bytecodes::_dload_2: 456 case Bytecodes::_dload_3: 457 state.lpush(); 458 break; 459 case Bytecodes::_aload_0: 460 state.apush(state._vars[0]); 461 break; 462 case Bytecodes::_aload_1: 463 state.apush(state._vars[1]); 464 break; 465 case Bytecodes::_aload_2: 466 state.apush(state._vars[2]); 467 break; 468 case Bytecodes::_aload_3: 469 state.apush(state._vars[3]); 470 break; 471 case Bytecodes::_iaload: 472 case Bytecodes::_faload: 473 case Bytecodes::_baload: 474 case Bytecodes::_caload: 475 case Bytecodes::_saload: 476 state.spop(); 477 set_method_escape(state.apop()); 478 state.spush(); 479 break; 480 case Bytecodes::_laload: 481 case Bytecodes::_daload: 482 state.spop(); 483 set_method_escape(state.apop()); 484 state.lpush(); 485 break; 486 case Bytecodes::_aaload: 487 { state.spop(); 488 ArgumentMap array = state.apop(); 489 set_method_escape(array); 490 state.apush(unknown_obj); 491 set_dirty(array); 492 } 493 break; 494 case Bytecodes::_istore: 495 case Bytecodes::_fstore: 496 case Bytecodes::_istore_0: 497 case Bytecodes::_istore_1: 498 case Bytecodes::_istore_2: 499 case Bytecodes::_istore_3: 500 case Bytecodes::_fstore_0: 501 case Bytecodes::_fstore_1: 502 case Bytecodes::_fstore_2: 503 case Bytecodes::_fstore_3: 504 state.spop(); 505 break; 506 case Bytecodes::_lstore: 507 case Bytecodes::_dstore: 508 case Bytecodes::_lstore_0: 509 case Bytecodes::_lstore_1: 510 case Bytecodes::_lstore_2: 511 case Bytecodes::_lstore_3: 512 case Bytecodes::_dstore_0: 513 case Bytecodes::_dstore_1: 514 case Bytecodes::_dstore_2: 515 case Bytecodes::_dstore_3: 516 state.lpop(); 517 break; 518 case Bytecodes::_astore: 519 state._vars[s.get_index()] = state.apop(); 520 break; 521 case Bytecodes::_astore_0: 522 state._vars[0] = state.apop(); 523 break; 524 case Bytecodes::_astore_1: 525 state._vars[1] = state.apop(); 526 break; 527 case Bytecodes::_astore_2: 528 state._vars[2] = state.apop(); 529 break; 530 case Bytecodes::_astore_3: 531 state._vars[3] = state.apop(); 532 break; 533 case Bytecodes::_iastore: 534 case Bytecodes::_fastore: 535 case Bytecodes::_bastore: 536 case Bytecodes::_castore: 537 case Bytecodes::_sastore: 538 { 539 state.spop(); 540 state.spop(); 541 ArgumentMap arr = state.apop(); 542 set_method_escape(arr); 543 set_modified(arr, OFFSET_ANY, type2size[T_INT]*HeapWordSize); 544 break; 545 } 546 case Bytecodes::_lastore: 547 case Bytecodes::_dastore: 548 { 549 state.lpop(); 550 state.spop(); 551 ArgumentMap arr = state.apop(); 552 set_method_escape(arr); 553 set_modified(arr, OFFSET_ANY, type2size[T_LONG]*HeapWordSize); 554 break; 555 } 556 case Bytecodes::_aastore: 557 { 558 set_global_escape(state.apop()); 559 state.spop(); 560 ArgumentMap arr = state.apop(); 561 set_modified(arr, OFFSET_ANY, type2size[T_OBJECT]*HeapWordSize); 562 break; 563 } 564 case Bytecodes::_pop: 565 state.raw_pop(); 566 break; 567 case Bytecodes::_pop2: 568 state.raw_pop(); 569 state.raw_pop(); 570 break; 571 case Bytecodes::_dup: 572 { ArgumentMap w1 = state.raw_pop(); 573 state.raw_push(w1); 574 state.raw_push(w1); 575 } 576 break; 577 case Bytecodes::_dup_x1: 578 { ArgumentMap w1 = state.raw_pop(); 579 ArgumentMap w2 = state.raw_pop(); 580 state.raw_push(w1); 581 state.raw_push(w2); 582 state.raw_push(w1); 583 } 584 break; 585 case Bytecodes::_dup_x2: 586 { ArgumentMap w1 = state.raw_pop(); 587 ArgumentMap w2 = state.raw_pop(); 588 ArgumentMap w3 = state.raw_pop(); 589 state.raw_push(w1); 590 state.raw_push(w3); 591 state.raw_push(w2); 592 state.raw_push(w1); 593 } 594 break; 595 case Bytecodes::_dup2: 596 { ArgumentMap w1 = state.raw_pop(); 597 ArgumentMap w2 = state.raw_pop(); 598 state.raw_push(w2); 599 state.raw_push(w1); 600 state.raw_push(w2); 601 state.raw_push(w1); 602 } 603 break; 604 case Bytecodes::_dup2_x1: 605 { ArgumentMap w1 = state.raw_pop(); 606 ArgumentMap w2 = state.raw_pop(); 607 ArgumentMap w3 = state.raw_pop(); 608 state.raw_push(w2); 609 state.raw_push(w1); 610 state.raw_push(w3); 611 state.raw_push(w2); 612 state.raw_push(w1); 613 } 614 break; 615 case Bytecodes::_dup2_x2: 616 { ArgumentMap w1 = state.raw_pop(); 617 ArgumentMap w2 = state.raw_pop(); 618 ArgumentMap w3 = state.raw_pop(); 619 ArgumentMap w4 = state.raw_pop(); 620 state.raw_push(w2); 621 state.raw_push(w1); 622 state.raw_push(w4); 623 state.raw_push(w3); 624 state.raw_push(w2); 625 state.raw_push(w1); 626 } 627 break; 628 case Bytecodes::_swap: 629 { ArgumentMap w1 = state.raw_pop(); 630 ArgumentMap w2 = state.raw_pop(); 631 state.raw_push(w1); 632 state.raw_push(w2); 633 } 634 break; 635 case Bytecodes::_iadd: 636 case Bytecodes::_fadd: 637 case Bytecodes::_isub: 638 case Bytecodes::_fsub: 639 case Bytecodes::_imul: 640 case Bytecodes::_fmul: 641 case Bytecodes::_idiv: 642 case Bytecodes::_fdiv: 643 case Bytecodes::_irem: 644 case Bytecodes::_frem: 645 case Bytecodes::_iand: 646 case Bytecodes::_ior: 647 case Bytecodes::_ixor: 648 state.spop(); 649 state.spop(); 650 state.spush(); 651 break; 652 case Bytecodes::_ladd: 653 case Bytecodes::_dadd: 654 case Bytecodes::_lsub: 655 case Bytecodes::_dsub: 656 case Bytecodes::_lmul: 657 case Bytecodes::_dmul: 658 case Bytecodes::_ldiv: 659 case Bytecodes::_ddiv: 660 case Bytecodes::_lrem: 661 case Bytecodes::_drem: 662 case Bytecodes::_land: 663 case Bytecodes::_lor: 664 case Bytecodes::_lxor: 665 state.lpop(); 666 state.lpop(); 667 state.lpush(); 668 break; 669 case Bytecodes::_ishl: 670 case Bytecodes::_ishr: 671 case Bytecodes::_iushr: 672 state.spop(); 673 state.spop(); 674 state.spush(); 675 break; 676 case Bytecodes::_lshl: 677 case Bytecodes::_lshr: 678 case Bytecodes::_lushr: 679 state.spop(); 680 state.lpop(); 681 state.lpush(); 682 break; 683 case Bytecodes::_ineg: 684 case Bytecodes::_fneg: 685 state.spop(); 686 state.spush(); 687 break; 688 case Bytecodes::_lneg: 689 case Bytecodes::_dneg: 690 state.lpop(); 691 state.lpush(); 692 break; 693 case Bytecodes::_iinc: 694 break; 695 case Bytecodes::_i2l: 696 case Bytecodes::_i2d: 697 case Bytecodes::_f2l: 698 case Bytecodes::_f2d: 699 state.spop(); 700 state.lpush(); 701 break; 702 case Bytecodes::_i2f: 703 case Bytecodes::_f2i: 704 state.spop(); 705 state.spush(); 706 break; 707 case Bytecodes::_l2i: 708 case Bytecodes::_l2f: 709 case Bytecodes::_d2i: 710 case Bytecodes::_d2f: 711 state.lpop(); 712 state.spush(); 713 break; 714 case Bytecodes::_l2d: 715 case Bytecodes::_d2l: 716 state.lpop(); 717 state.lpush(); 718 break; 719 case Bytecodes::_i2b: 720 case Bytecodes::_i2c: 721 case Bytecodes::_i2s: 722 state.spop(); 723 state.spush(); 724 break; 725 case Bytecodes::_lcmp: 726 case Bytecodes::_dcmpl: 727 case Bytecodes::_dcmpg: 728 state.lpop(); 729 state.lpop(); 730 state.spush(); 731 break; 732 case Bytecodes::_fcmpl: 733 case Bytecodes::_fcmpg: 734 state.spop(); 735 state.spop(); 736 state.spush(); 737 break; 738 case Bytecodes::_ifeq: 739 case Bytecodes::_ifne: 740 case Bytecodes::_iflt: 741 case Bytecodes::_ifge: 742 case Bytecodes::_ifgt: 743 case Bytecodes::_ifle: 744 { 745 state.spop(); 746 int dest_bci = s.get_dest(); 747 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 748 assert(s.next_bci() == limit_bci, "branch must end block"); 749 successors.push(_methodBlocks->block_containing(dest_bci)); 750 break; 751 } 752 case Bytecodes::_if_icmpeq: 753 case Bytecodes::_if_icmpne: 754 case Bytecodes::_if_icmplt: 755 case Bytecodes::_if_icmpge: 756 case Bytecodes::_if_icmpgt: 757 case Bytecodes::_if_icmple: 758 { 759 state.spop(); 760 state.spop(); 761 int dest_bci = s.get_dest(); 762 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 763 assert(s.next_bci() == limit_bci, "branch must end block"); 764 successors.push(_methodBlocks->block_containing(dest_bci)); 765 break; 766 } 767 case Bytecodes::_if_acmpeq: 768 case Bytecodes::_if_acmpne: 769 { 770 set_method_escape(state.apop()); 771 set_method_escape(state.apop()); 772 int dest_bci = s.get_dest(); 773 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 774 assert(s.next_bci() == limit_bci, "branch must end block"); 775 successors.push(_methodBlocks->block_containing(dest_bci)); 776 break; 777 } 778 case Bytecodes::_goto: 779 { 780 int dest_bci = s.get_dest(); 781 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 782 assert(s.next_bci() == limit_bci, "branch must end block"); 783 successors.push(_methodBlocks->block_containing(dest_bci)); 784 fall_through = false; 785 break; 786 } 787 case Bytecodes::_jsr: 788 { 789 int dest_bci = s.get_dest(); 790 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 791 assert(s.next_bci() == limit_bci, "branch must end block"); 792 state.apush(empty_map); 793 successors.push(_methodBlocks->block_containing(dest_bci)); 794 fall_through = false; 795 break; 796 } 797 case Bytecodes::_ret: 798 // we don't track the destination of a "ret" instruction 799 assert(s.next_bci() == limit_bci, "branch must end block"); 800 fall_through = false; 801 break; 802 case Bytecodes::_return: 803 assert(s.next_bci() == limit_bci, "return must end block"); 804 fall_through = false; 805 break; 806 case Bytecodes::_tableswitch: 807 { 808 state.spop(); 809 Bytecode_tableswitch sw(&s); 810 int len = sw.length(); 811 int dest_bci; 812 for (int i = 0; i < len; i++) { 813 dest_bci = s.cur_bci() + sw.dest_offset_at(i); 814 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 815 successors.push(_methodBlocks->block_containing(dest_bci)); 816 } 817 dest_bci = s.cur_bci() + sw.default_offset(); 818 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 819 successors.push(_methodBlocks->block_containing(dest_bci)); 820 assert(s.next_bci() == limit_bci, "branch must end block"); 821 fall_through = false; 822 break; 823 } 824 case Bytecodes::_lookupswitch: 825 { 826 state.spop(); 827 Bytecode_lookupswitch sw(&s); 828 int len = sw.number_of_pairs(); 829 int dest_bci; 830 for (int i = 0; i < len; i++) { 831 dest_bci = s.cur_bci() + sw.pair_at(i).offset(); 832 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 833 successors.push(_methodBlocks->block_containing(dest_bci)); 834 } 835 dest_bci = s.cur_bci() + sw.default_offset(); 836 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 837 successors.push(_methodBlocks->block_containing(dest_bci)); 838 fall_through = false; 839 break; 840 } 841 case Bytecodes::_ireturn: 842 case Bytecodes::_freturn: 843 state.spop(); 844 fall_through = false; 845 break; 846 case Bytecodes::_lreturn: 847 case Bytecodes::_dreturn: 848 state.lpop(); 849 fall_through = false; 850 break; 851 case Bytecodes::_areturn: 852 set_returned(state.apop()); 853 fall_through = false; 854 break; 855 case Bytecodes::_getstatic: 856 case Bytecodes::_getfield: 857 { bool ignored_will_link; 858 ciField* field = s.get_field(ignored_will_link); 859 BasicType field_type = field->type()->basic_type(); 860 if (s.cur_bc() != Bytecodes::_getstatic) { 861 set_method_escape(state.apop()); 862 } 863 if (field_type == T_OBJECT || field_type == T_ARRAY) { 864 state.apush(unknown_obj); 865 } else if (type2size[field_type] == 1) { 866 state.spush(); 867 } else { 868 state.lpush(); 869 } 870 } 871 break; 872 case Bytecodes::_putstatic: 873 case Bytecodes::_putfield: 874 { bool will_link; 875 ciField* field = s.get_field(will_link); 876 BasicType field_type = field->type()->basic_type(); 877 if (field_type == T_OBJECT || field_type == T_ARRAY) { 878 set_global_escape(state.apop()); 879 } else if (type2size[field_type] == 1) { 880 state.spop(); 881 } else { 882 state.lpop(); 883 } 884 if (s.cur_bc() != Bytecodes::_putstatic) { 885 ArgumentMap p = state.apop(); 886 set_method_escape(p); 887 set_modified(p, will_link ? field->offset() : OFFSET_ANY, type2size[field_type]*HeapWordSize); 888 } 889 } 890 break; 891 case Bytecodes::_invokevirtual: 892 case Bytecodes::_invokespecial: 893 case Bytecodes::_invokestatic: 894 case Bytecodes::_invokedynamic: 895 case Bytecodes::_invokeinterface: 896 { bool ignored_will_link; 897 ciSignature* declared_signature = NULL; 898 ciMethod* target = s.get_method(ignored_will_link, &declared_signature); 899 ciKlass* holder = s.get_declared_method_holder(); 900 assert(declared_signature != NULL, "cannot be null"); 901 // If the current bytecode has an attached appendix argument, 902 // push an unknown object to represent that argument. (Analysis 903 // of dynamic call sites, especially invokehandle calls, needs 904 // the appendix argument on the stack, in addition to "regular" arguments 905 // pushed onto the stack by bytecode instructions preceding the call.) 906 // 907 // The escape analyzer does _not_ use the ciBytecodeStream::has_appendix(s) 908 // method to determine whether the current bytecode has an appendix argument. 909 // The has_appendix() method obtains the appendix from the 910 // ConstantPoolCacheEntry::_f1 field, which can happen concurrently with 911 // resolution of dynamic call sites. Callees in the 912 // ciBytecodeStream::get_method() call above also access the _f1 field; 913 // interleaving the get_method() and has_appendix() calls in the current 914 // method with call site resolution can lead to an inconsistent view of 915 // the current method's argument count. In particular, some interleaving(s) 916 // can cause the method's argument count to not include the appendix, which 917 // then leads to stack over-/underflow in the escape analyzer. 918 // 919 // Instead of pushing the argument if has_appendix() is true, the escape analyzer 920 // pushes an appendix for all call sites targeted by invokedynamic and invokehandle 921 // instructions, except if the call site is the _invokeBasic intrinsic 922 // (that intrinsic is always targeted by an invokehandle instruction but does 923 // not have an appendix argument). 924 if (target->is_loaded() && 925 Bytecodes::has_optional_appendix(s.cur_bc_raw()) && 926 target->intrinsic_id() != vmIntrinsics::_invokeBasic) { 927 state.apush(unknown_obj); 928 } 929 // Pass in raw bytecode because we need to see invokehandle instructions. 930 invoke(state, s.cur_bc_raw(), target, holder); 931 // We are using the return type of the declared signature here because 932 // it might be a more concrete type than the one from the target (for 933 // e.g. invokedynamic and invokehandle). 934 ciType* return_type = declared_signature->return_type(); 935 if (!return_type->is_primitive_type()) { 936 state.apush(unknown_obj); 937 } else if (return_type->is_one_word()) { 938 state.spush(); 939 } else if (return_type->is_two_word()) { 940 state.lpush(); 941 } 942 } 943 break; 944 case Bytecodes::_new: 945 state.apush(allocated_obj); 946 break; 947 case Bytecodes::_newarray: 948 case Bytecodes::_anewarray: 949 state.spop(); 950 state.apush(allocated_obj); 951 break; 952 case Bytecodes::_multianewarray: 953 { int i = s.cur_bcp()[3]; 954 while (i-- > 0) state.spop(); 955 state.apush(allocated_obj); 956 } 957 break; 958 case Bytecodes::_arraylength: 959 set_method_escape(state.apop()); 960 state.spush(); 961 break; 962 case Bytecodes::_athrow: 963 set_global_escape(state.apop()); 964 fall_through = false; 965 break; 966 case Bytecodes::_checkcast: 967 { ArgumentMap obj = state.apop(); 968 set_method_escape(obj); 969 state.apush(obj); 970 } 971 break; 972 case Bytecodes::_instanceof: 973 set_method_escape(state.apop()); 974 state.spush(); 975 break; 976 case Bytecodes::_monitorenter: 977 case Bytecodes::_monitorexit: 978 state.apop(); 979 break; 980 case Bytecodes::_wide: 981 ShouldNotReachHere(); 982 break; 983 case Bytecodes::_ifnull: 984 case Bytecodes::_ifnonnull: 985 { 986 set_method_escape(state.apop()); 987 int dest_bci = s.get_dest(); 988 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 989 assert(s.next_bci() == limit_bci, "branch must end block"); 990 successors.push(_methodBlocks->block_containing(dest_bci)); 991 break; 992 } 993 case Bytecodes::_goto_w: 994 { 995 int dest_bci = s.get_far_dest(); 996 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 997 assert(s.next_bci() == limit_bci, "branch must end block"); 998 successors.push(_methodBlocks->block_containing(dest_bci)); 999 fall_through = false; 1000 break; 1001 } 1002 case Bytecodes::_jsr_w: 1003 { 1004 int dest_bci = s.get_far_dest(); 1005 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 1006 assert(s.next_bci() == limit_bci, "branch must end block"); 1007 state.apush(empty_map); 1008 successors.push(_methodBlocks->block_containing(dest_bci)); 1009 fall_through = false; 1010 break; 1011 } 1012 case Bytecodes::_breakpoint: 1013 break; 1014 default: 1015 ShouldNotReachHere(); 1016 break; 1017 } 1018 1019 } 1020 if (fall_through) { 1021 int fall_through_bci = s.cur_bci(); 1022 if (fall_through_bci < _method->code_size()) { 1023 assert(_methodBlocks->is_block_start(fall_through_bci), "must fall through to block start."); 1024 successors.push(_methodBlocks->block_containing(fall_through_bci)); 1025 } 1026 } 1027 } 1028 1029 void BCEscapeAnalyzer::merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state) { 1030 StateInfo *d_state = blockstates + dest->index(); 1031 int nlocals = _method->max_locals(); 1032 1033 // exceptions may cause transfer of control to handlers in the middle of a 1034 // block, so we don't merge the incoming state of exception handlers 1035 if (dest->is_handler()) 1036 return; 1037 if (!d_state->_initialized ) { 1038 // destination not initialized, just copy 1039 for (int i = 0; i < nlocals; i++) { 1040 d_state->_vars[i] = s_state->_vars[i]; 1041 } 1042 for (int i = 0; i < s_state->_stack_height; i++) { 1043 d_state->_stack[i] = s_state->_stack[i]; 1044 } 1045 d_state->_stack_height = s_state->_stack_height; 1046 d_state->_max_stack = s_state->_max_stack; 1047 d_state->_initialized = true; 1048 } else if (!dest->processed()) { 1049 // we have not yet walked the bytecodes of dest, we can merge 1050 // the states 1051 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match"); 1052 for (int i = 0; i < nlocals; i++) { 1053 d_state->_vars[i].set_union(s_state->_vars[i]); 1054 } 1055 for (int i = 0; i < s_state->_stack_height; i++) { 1056 d_state->_stack[i].set_union(s_state->_stack[i]); 1057 } 1058 } else { 1059 // the bytecodes of dest have already been processed, mark any 1060 // arguments in the source state which are not in the dest state 1061 // as global escape. 1062 // Future refinement: we only need to mark these variable to the 1063 // maximum escape of any variables in dest state 1064 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match"); 1065 ArgumentMap extra_vars; 1066 for (int i = 0; i < nlocals; i++) { 1067 ArgumentMap t; 1068 t = s_state->_vars[i]; 1069 t.set_difference(d_state->_vars[i]); 1070 extra_vars.set_union(t); 1071 } 1072 for (int i = 0; i < s_state->_stack_height; i++) { 1073 ArgumentMap t; 1074 //extra_vars |= !d_state->_vars[i] & s_state->_vars[i]; 1075 t.clear(); 1076 t = s_state->_stack[i]; 1077 t.set_difference(d_state->_stack[i]); 1078 extra_vars.set_union(t); 1079 } 1080 set_global_escape(extra_vars, true); 1081 } 1082 } 1083 1084 void BCEscapeAnalyzer::iterate_blocks(Arena *arena) { 1085 int numblocks = _methodBlocks->num_blocks(); 1086 int stkSize = _method->max_stack(); 1087 int numLocals = _method->max_locals(); 1088 StateInfo state; 1089 1090 int datacount = (numblocks + 1) * (stkSize + numLocals); 1091 int datasize = datacount * sizeof(ArgumentMap); 1092 StateInfo *blockstates = (StateInfo *) arena->Amalloc(numblocks * sizeof(StateInfo)); 1093 ArgumentMap *statedata = (ArgumentMap *) arena->Amalloc(datasize); 1094 for (int i = 0; i < datacount; i++) ::new ((void*)&statedata[i]) ArgumentMap(); 1095 ArgumentMap *dp = statedata; 1096 state._vars = dp; 1097 dp += numLocals; 1098 state._stack = dp; 1099 dp += stkSize; 1100 state._initialized = false; 1101 state._max_stack = stkSize; 1102 for (int i = 0; i < numblocks; i++) { 1103 blockstates[i]._vars = dp; 1104 dp += numLocals; 1105 blockstates[i]._stack = dp; 1106 dp += stkSize; 1107 blockstates[i]._initialized = false; 1108 blockstates[i]._stack_height = 0; 1109 blockstates[i]._max_stack = stkSize; 1110 } 1111 GrowableArray<ciBlock *> worklist(arena, numblocks / 4, 0, NULL); 1112 GrowableArray<ciBlock *> successors(arena, 4, 0, NULL); 1113 1114 _methodBlocks->clear_processed(); 1115 1116 // initialize block 0 state from method signature 1117 ArgumentMap allVars; // all oop arguments to method 1118 ciSignature* sig = method()->signature(); 1119 int j = 0; 1120 ciBlock* first_blk = _methodBlocks->block_containing(0); 1121 int fb_i = first_blk->index(); 1122 if (!method()->is_static()) { 1123 // record information for "this" 1124 blockstates[fb_i]._vars[j].set(j); 1125 allVars.add(j); 1126 j++; 1127 } 1128 for (int i = 0; i < sig->count(); i++) { 1129 ciType* t = sig->type_at(i); 1130 if (!t->is_primitive_type()) { 1131 blockstates[fb_i]._vars[j].set(j); 1132 allVars.add(j); 1133 } 1134 j += t->size(); 1135 } 1136 blockstates[fb_i]._initialized = true; 1137 assert(j == _arg_size, "just checking"); 1138 1139 ArgumentMap unknown_map; 1140 unknown_map.add_unknown(); 1141 1142 worklist.push(first_blk); 1143 while(worklist.length() > 0) { 1144 ciBlock *blk = worklist.pop(); 1145 StateInfo *blkState = blockstates + blk->index(); 1146 if (blk->is_handler() || blk->is_ret_target()) { 1147 // for an exception handler or a target of a ret instruction, we assume the worst case, 1148 // that any variable could contain any argument 1149 for (int i = 0; i < numLocals; i++) { 1150 state._vars[i] = allVars; 1151 } 1152 if (blk->is_handler()) { 1153 state._stack_height = 1; 1154 } else { 1155 state._stack_height = blkState->_stack_height; 1156 } 1157 for (int i = 0; i < state._stack_height; i++) { 1158 // ??? should this be unknown_map ??? 1159 state._stack[i] = allVars; 1160 } 1161 } else { 1162 for (int i = 0; i < numLocals; i++) { 1163 state._vars[i] = blkState->_vars[i]; 1164 } 1165 for (int i = 0; i < blkState->_stack_height; i++) { 1166 state._stack[i] = blkState->_stack[i]; 1167 } 1168 state._stack_height = blkState->_stack_height; 1169 } 1170 iterate_one_block(blk, state, successors); 1171 // if this block has any exception handlers, push them 1172 // onto successor list 1173 if (blk->has_handler()) { 1174 DEBUG_ONLY(int handler_count = 0;) 1175 int blk_start = blk->start_bci(); 1176 int blk_end = blk->limit_bci(); 1177 for (int i = 0; i < numblocks; i++) { 1178 ciBlock *b = _methodBlocks->block(i); 1179 if (b->is_handler()) { 1180 int ex_start = b->ex_start_bci(); 1181 int ex_end = b->ex_limit_bci(); 1182 if ((ex_start >= blk_start && ex_start < blk_end) || 1183 (ex_end > blk_start && ex_end <= blk_end)) { 1184 successors.push(b); 1185 } 1186 DEBUG_ONLY(handler_count++;) 1187 } 1188 } 1189 assert(handler_count > 0, "must find at least one handler"); 1190 } 1191 // merge computed variable state with successors 1192 while(successors.length() > 0) { 1193 ciBlock *succ = successors.pop(); 1194 merge_block_states(blockstates, succ, &state); 1195 if (!succ->processed()) 1196 worklist.push(succ); 1197 } 1198 } 1199 } 1200 1201 bool BCEscapeAnalyzer::do_analysis() { 1202 Arena* arena = CURRENT_ENV->arena(); 1203 // identify basic blocks 1204 _methodBlocks = _method->get_method_blocks(); 1205 1206 iterate_blocks(arena); 1207 // TEMPORARY 1208 return true; 1209 } 1210 1211 vmIntrinsics::ID BCEscapeAnalyzer::known_intrinsic() { 1212 vmIntrinsics::ID iid = method()->intrinsic_id(); 1213 1214 if (iid == vmIntrinsics::_getClass || 1215 iid == vmIntrinsics::_hashCode) 1216 return iid; 1217 else 1218 return vmIntrinsics::_none; 1219 } 1220 1221 bool BCEscapeAnalyzer::compute_escape_for_intrinsic(vmIntrinsics::ID iid) { 1222 ArgumentMap arg; 1223 arg.clear(); 1224 switch (iid) { 1225 case vmIntrinsics::_getClass: 1226 _return_local = false; 1227 break; 1228 case vmIntrinsics::_hashCode: 1229 // initialized state is correct 1230 break; 1231 default: 1232 assert(false, "unexpected intrinsic"); 1233 } 1234 return true; 1235 } 1236 1237 void BCEscapeAnalyzer::initialize() { 1238 int i; 1239 1240 // clear escape information (method may have been deoptimized) 1241 methodData()->clear_escape_info(); 1242 1243 // initialize escape state of object parameters 1244 ciSignature* sig = method()->signature(); 1245 int j = 0; 1246 if (!method()->is_static()) { 1247 _arg_local.set(0); 1248 _arg_stack.set(0); 1249 j++; 1250 } 1251 for (i = 0; i < sig->count(); i++) { 1252 ciType* t = sig->type_at(i); 1253 if (!t->is_primitive_type()) { 1254 _arg_local.set(j); 1255 _arg_stack.set(j); 1256 } 1257 j += t->size(); 1258 } 1259 assert(j == _arg_size, "just checking"); 1260 1261 // start with optimistic assumption 1262 ciType *rt = _method->return_type(); 1263 if (rt->is_primitive_type()) { 1264 _return_local = false; 1265 _return_allocated = false; 1266 } else { 1267 _return_local = true; 1268 _return_allocated = true; 1269 } 1270 _allocated_escapes = false; 1271 _unknown_modified = false; 1272 } 1273 1274 void BCEscapeAnalyzer::clear_escape_info() { 1275 ciSignature* sig = method()->signature(); 1276 int arg_count = sig->count(); 1277 ArgumentMap var; 1278 if (!method()->is_static()) { 1279 arg_count++; // allow for "this" 1280 } 1281 for (int i = 0; i < arg_count; i++) { 1282 set_arg_modified(i, OFFSET_ANY, 4); 1283 var.clear(); 1284 var.set(i); 1285 set_modified(var, OFFSET_ANY, 4); 1286 set_global_escape(var); 1287 } 1288 _arg_local.Clear(); 1289 _arg_stack.Clear(); 1290 _arg_returned.Clear(); 1291 _return_local = false; 1292 _return_allocated = false; 1293 _allocated_escapes = true; 1294 _unknown_modified = true; 1295 } 1296 1297 1298 void BCEscapeAnalyzer::compute_escape_info() { 1299 int i; 1300 assert(!methodData()->has_escape_info(), "do not overwrite escape info"); 1301 1302 vmIntrinsics::ID iid = known_intrinsic(); 1303 1304 // check if method can be analyzed 1305 if (iid == vmIntrinsics::_none && (method()->is_abstract() || method()->is_native() || !method()->holder()->is_initialized() 1306 || _level > MaxBCEAEstimateLevel 1307 || method()->code_size() > MaxBCEAEstimateSize)) { 1308 if (BCEATraceLevel >= 1) { 1309 tty->print("Skipping method because: "); 1310 if (method()->is_abstract()) 1311 tty->print_cr("method is abstract."); 1312 else if (method()->is_native()) 1313 tty->print_cr("method is native."); 1314 else if (!method()->holder()->is_initialized()) 1315 tty->print_cr("class of method is not initialized."); 1316 else if (_level > MaxBCEAEstimateLevel) 1317 tty->print_cr("level (%d) exceeds MaxBCEAEstimateLevel (%d).", 1318 _level, (int) MaxBCEAEstimateLevel); 1319 else if (method()->code_size() > MaxBCEAEstimateSize) 1320 tty->print_cr("code size (%d) exceeds MaxBCEAEstimateSize (%d).", 1321 method()->code_size(), (int) MaxBCEAEstimateSize); 1322 else 1323 ShouldNotReachHere(); 1324 } 1325 clear_escape_info(); 1326 1327 return; 1328 } 1329 1330 if (BCEATraceLevel >= 1) { 1331 tty->print("[EA] estimating escape information for"); 1332 if (iid != vmIntrinsics::_none) 1333 tty->print(" intrinsic"); 1334 method()->print_short_name(); 1335 tty->print_cr(" (%d bytes)", method()->code_size()); 1336 } 1337 1338 bool success; 1339 1340 initialize(); 1341 1342 // Do not scan method if it has no object parameters and 1343 // does not returns an object (_return_allocated is set in initialize()). 1344 if (_arg_local.Size() == 0 && !_return_allocated) { 1345 // Clear all info since method's bytecode was not analysed and 1346 // set pessimistic escape information. 1347 clear_escape_info(); 1348 methodData()->set_eflag(MethodData::allocated_escapes); 1349 methodData()->set_eflag(MethodData::unknown_modified); 1350 methodData()->set_eflag(MethodData::estimated); 1351 return; 1352 } 1353 1354 if (iid != vmIntrinsics::_none) 1355 success = compute_escape_for_intrinsic(iid); 1356 else { 1357 success = do_analysis(); 1358 } 1359 1360 // don't store interprocedural escape information if it introduces 1361 // dependencies or if method data is empty 1362 // 1363 if (!has_dependencies() && !methodData()->is_empty()) { 1364 for (i = 0; i < _arg_size; i++) { 1365 if (_arg_local.test(i)) { 1366 assert(_arg_stack.test(i), "inconsistent escape info"); 1367 methodData()->set_arg_local(i); 1368 methodData()->set_arg_stack(i); 1369 } else if (_arg_stack.test(i)) { 1370 methodData()->set_arg_stack(i); 1371 } 1372 if (_arg_returned.test(i)) { 1373 methodData()->set_arg_returned(i); 1374 } 1375 methodData()->set_arg_modified(i, _arg_modified[i]); 1376 } 1377 if (_return_local) { 1378 methodData()->set_eflag(MethodData::return_local); 1379 } 1380 if (_return_allocated) { 1381 methodData()->set_eflag(MethodData::return_allocated); 1382 } 1383 if (_allocated_escapes) { 1384 methodData()->set_eflag(MethodData::allocated_escapes); 1385 } 1386 if (_unknown_modified) { 1387 methodData()->set_eflag(MethodData::unknown_modified); 1388 } 1389 methodData()->set_eflag(MethodData::estimated); 1390 } 1391 } 1392 1393 void BCEscapeAnalyzer::read_escape_info() { 1394 assert(methodData()->has_escape_info(), "no escape info available"); 1395 1396 // read escape information from method descriptor 1397 for (int i = 0; i < _arg_size; i++) { 1398 if (methodData()->is_arg_local(i)) 1399 _arg_local.set(i); 1400 if (methodData()->is_arg_stack(i)) 1401 _arg_stack.set(i); 1402 if (methodData()->is_arg_returned(i)) 1403 _arg_returned.set(i); 1404 _arg_modified[i] = methodData()->arg_modified(i); 1405 } 1406 _return_local = methodData()->eflag_set(MethodData::return_local); 1407 _return_allocated = methodData()->eflag_set(MethodData::return_allocated); 1408 _allocated_escapes = methodData()->eflag_set(MethodData::allocated_escapes); 1409 _unknown_modified = methodData()->eflag_set(MethodData::unknown_modified); 1410 1411 } 1412 1413 #ifndef PRODUCT 1414 void BCEscapeAnalyzer::dump() { 1415 tty->print("[EA] estimated escape information for"); 1416 method()->print_short_name(); 1417 tty->print_cr(has_dependencies() ? " (not stored)" : ""); 1418 tty->print(" non-escaping args: "); 1419 _arg_local.print(); 1420 tty->print(" stack-allocatable args: "); 1421 _arg_stack.print(); 1422 if (_return_local) { 1423 tty->print(" returned args: "); 1424 _arg_returned.print(); 1425 } else if (is_return_allocated()) { 1426 tty->print_cr(" return allocated value"); 1427 } else { 1428 tty->print_cr(" return non-local value"); 1429 } 1430 tty->print(" modified args: "); 1431 for (int i = 0; i < _arg_size; i++) { 1432 if (_arg_modified[i] == 0) 1433 tty->print(" 0"); 1434 else 1435 tty->print(" 0x%x", _arg_modified[i]); 1436 } 1437 tty->cr(); 1438 tty->print(" flags: "); 1439 if (_return_allocated) 1440 tty->print(" return_allocated"); 1441 if (_allocated_escapes) 1442 tty->print(" allocated_escapes"); 1443 if (_unknown_modified) 1444 tty->print(" unknown_modified"); 1445 tty->cr(); 1446 } 1447 #endif 1448 1449 BCEscapeAnalyzer::BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent) 1450 : _conservative(method == NULL || !EstimateArgEscape) 1451 , _arena(CURRENT_ENV->arena()) 1452 , _method(method) 1453 , _methodData(method ? method->method_data() : NULL) 1454 , _arg_size(method ? method->arg_size() : 0) 1455 , _arg_local(_arena) 1456 , _arg_stack(_arena) 1457 , _arg_returned(_arena) 1458 , _dirty(_arena) 1459 , _return_local(false) 1460 , _return_allocated(false) 1461 , _allocated_escapes(false) 1462 , _unknown_modified(false) 1463 , _dependencies(_arena, 4, 0, NULL) 1464 , _parent(parent) 1465 , _level(parent == NULL ? 0 : parent->level() + 1) { 1466 if (!_conservative) { 1467 _arg_local.Clear(); 1468 _arg_stack.Clear(); 1469 _arg_returned.Clear(); 1470 _dirty.Clear(); 1471 Arena* arena = CURRENT_ENV->arena(); 1472 _arg_modified = (uint *) arena->Amalloc(_arg_size * sizeof(uint)); 1473 Copy::zero_to_bytes(_arg_modified, _arg_size * sizeof(uint)); 1474 1475 if (methodData() == NULL) 1476 return; 1477 if (methodData()->has_escape_info()) { 1478 TRACE_BCEA(2, tty->print_cr("[EA] Reading previous results for %s.%s", 1479 method->holder()->name()->as_utf8(), 1480 method->name()->as_utf8())); 1481 read_escape_info(); 1482 } else { 1483 TRACE_BCEA(2, tty->print_cr("[EA] computing results for %s.%s", 1484 method->holder()->name()->as_utf8(), 1485 method->name()->as_utf8())); 1486 1487 compute_escape_info(); 1488 methodData()->update_escape_info(); 1489 } 1490 #ifndef PRODUCT 1491 if (BCEATraceLevel >= 3) { 1492 // dump escape information 1493 dump(); 1494 } 1495 #endif 1496 } 1497 } 1498 1499 void BCEscapeAnalyzer::copy_dependencies(Dependencies *deps) { 1500 if (ciEnv::current()->jvmti_can_hotswap_or_post_breakpoint()) { 1501 // Also record evol dependencies so redefinition of the 1502 // callee will trigger recompilation. 1503 deps->assert_evol_method(method()); 1504 } 1505 for (int i = 0; i < _dependencies.length(); i+=2) { 1506 ciKlass *k = _dependencies.at(i)->as_klass(); 1507 ciMethod *m = _dependencies.at(i+1)->as_method(); 1508 deps->assert_unique_concrete_method(k, m); 1509 } 1510 }