1 /* 2 * Copyright (c) 2005, 2021, 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 "classfile/vmIntrinsics.hpp" 27 #include "ci/bcEscapeAnalyzer.hpp" 28 #include "ci/ciConstant.hpp" 29 #include "ci/ciField.hpp" 30 #include "ci/ciMethodBlocks.hpp" 31 #include "ci/ciStreams.hpp" 32 #include "compiler/compiler_globals.hpp" 33 #include "interpreter/bytecode.hpp" 34 #include "oops/oop.inline.hpp" 35 #include "utilities/align.hpp" 36 #include "utilities/bitMap.inline.hpp" 37 #include "utilities/copy.hpp" 38 39 #ifndef PRODUCT 40 #define TRACE_BCEA(level, code) \ 41 if (EstimateArgEscape && BCEATraceLevel >= level) { \ 42 code; \ 43 } 44 #else 45 #define TRACE_BCEA(level, code) 46 #endif 47 48 // Maintain a map of which arguments a local variable or 49 // stack slot may contain. In addition to tracking 50 // arguments, it tracks two special values, "allocated" 51 // which represents any object allocated in the current 52 // method, and "unknown" which is any other object. 53 // Up to 30 arguments are handled, with the last one 54 // representing summary information for any extra arguments 55 class BCEscapeAnalyzer::ArgumentMap { 56 uint _bits; 57 enum {MAXBIT = 29, 58 ALLOCATED = 1, 59 UNKNOWN = 2}; 60 61 uint int_to_bit(uint e) const { 62 if (e > MAXBIT) 63 e = MAXBIT; 64 return (1 << (e + 2)); 65 } 66 67 public: 68 ArgumentMap() { _bits = 0;} 69 void set_bits(uint bits) { _bits = bits;} 70 uint get_bits() const { return _bits;} 71 void clear() { _bits = 0;} 72 void set_all() { _bits = ~0u; } 73 bool is_empty() const { return _bits == 0; } 74 bool contains(uint var) const { return (_bits & int_to_bit(var)) != 0; } 75 bool is_singleton(uint var) const { return (_bits == int_to_bit(var)); } 76 bool contains_unknown() const { return (_bits & UNKNOWN) != 0; } 77 bool contains_allocated() const { return (_bits & ALLOCATED) != 0; } 78 bool contains_vars() const { return (_bits & (((1 << MAXBIT) -1) << 2)) != 0; } 79 void set(uint var) { _bits = int_to_bit(var); } 80 void add(uint var) { _bits |= int_to_bit(var); } 81 void add_unknown() { _bits = UNKNOWN; } 82 void add_allocated() { _bits = ALLOCATED; } 83 void set_union(const ArgumentMap &am) { _bits |= am._bits; } 84 void set_difference(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.remove(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_modified(ArgumentMap vars, int offs, int size) { 192 193 for (int i = 0; i < _arg_size; i++) { 194 if (vars.contains(i)) { 195 set_arg_modified(i, offs, size); 196 } 197 } 198 if (vars.contains_unknown()) 199 _unknown_modified = true; 200 } 201 202 bool BCEscapeAnalyzer::is_recursive_call(ciMethod* callee) { 203 for (BCEscapeAnalyzer* scope = this; scope != NULL; scope = scope->_parent) { 204 if (scope->method() == callee) { 205 return true; 206 } 207 } 208 return false; 209 } 210 211 bool BCEscapeAnalyzer::is_arg_modified(int arg, int offset, int size_in_bytes) { 212 if (offset == OFFSET_ANY) 213 return _arg_modified[arg] != 0; 214 assert(arg >= 0 && arg < _arg_size, "must be an argument."); 215 bool modified = false; 216 int l = offset / HeapWordSize; 217 int h = align_up(offset + size_in_bytes, HeapWordSize) / HeapWordSize; 218 if (l > ARG_OFFSET_MAX) 219 l = ARG_OFFSET_MAX; 220 if (h > ARG_OFFSET_MAX+1) 221 h = ARG_OFFSET_MAX + 1; 222 for (int i = l; i < h; i++) { 223 modified = modified || (_arg_modified[arg] & (1 << i)) != 0; 224 } 225 return modified; 226 } 227 228 void BCEscapeAnalyzer::set_arg_modified(int arg, int offset, int size_in_bytes) { 229 if (offset == OFFSET_ANY) { 230 _arg_modified[arg] = (uint) -1; 231 return; 232 } 233 assert(arg >= 0 && arg < _arg_size, "must be an argument."); 234 int l = offset / HeapWordSize; 235 int h = align_up(offset + size_in_bytes, HeapWordSize) / HeapWordSize; 236 if (l > ARG_OFFSET_MAX) 237 l = ARG_OFFSET_MAX; 238 if (h > ARG_OFFSET_MAX+1) 239 h = ARG_OFFSET_MAX + 1; 240 for (int i = l; i < h; i++) { 241 _arg_modified[arg] |= (1 << i); 242 } 243 } 244 245 void BCEscapeAnalyzer::invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder) { 246 int i; 247 248 // retrieve information about the callee 249 ciInstanceKlass* klass = target->holder(); 250 ciInstanceKlass* calling_klass = method()->holder(); 251 ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder); 252 ciInstanceKlass* actual_recv = callee_holder; 253 254 // Some methods are obviously bindable without any type checks so 255 // convert them directly to an invokespecial or invokestatic. 256 if (target->is_loaded() && !target->is_abstract() && target->can_be_statically_bound()) { 257 switch (code) { 258 case Bytecodes::_invokevirtual: 259 code = Bytecodes::_invokespecial; 260 break; 261 case Bytecodes::_invokehandle: 262 code = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokespecial; 263 break; 264 default: 265 break; 266 } 267 } 268 269 // compute size of arguments 270 int arg_size = target->invoke_arg_size(code); 271 int arg_base = MAX2(state._stack_height - arg_size, 0); 272 273 // direct recursive calls are skipped if they can be bound statically without introducing 274 // dependencies and if parameters are passed at the same position as in the current method 275 // other calls are skipped if there are no non-escaped arguments passed to them 276 bool directly_recursive = (method() == target) && 277 (code != Bytecodes::_invokevirtual || target->is_final_method() || state._stack[arg_base] .is_empty()); 278 279 // check if analysis of callee can safely be skipped 280 bool skip_callee = true; 281 for (i = state._stack_height - 1; i >= arg_base && skip_callee; i--) { 282 ArgumentMap arg = state._stack[i]; 283 skip_callee = !is_argument(arg) || !is_arg_stack(arg) || (directly_recursive && arg.is_singleton(i - arg_base)); 284 } 285 // For now we conservatively skip invokedynamic. 286 if (code == Bytecodes::_invokedynamic) { 287 skip_callee = true; 288 } 289 if (skip_callee) { 290 TRACE_BCEA(3, tty->print_cr("[EA] skipping method %s::%s", holder->name()->as_utf8(), target->name()->as_utf8())); 291 for (i = 0; i < arg_size; i++) { 292 set_method_escape(state.raw_pop()); 293 } 294 _unknown_modified = true; // assume the worst since we don't analyze the called method 295 return; 296 } 297 298 // determine actual method (use CHA if necessary) 299 ciMethod* inline_target = NULL; 300 if (target->is_loaded() && klass->is_loaded() 301 && (klass->is_initialized() || (klass->is_interface() && target->holder()->is_initialized()))) { 302 if (code == Bytecodes::_invokestatic 303 || code == Bytecodes::_invokespecial 304 || (code == Bytecodes::_invokevirtual && target->is_final_method())) { 305 inline_target = target; 306 } else { 307 inline_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv); 308 } 309 } 310 311 if (inline_target != NULL && !is_recursive_call(inline_target)) { 312 // analyze callee 313 BCEscapeAnalyzer analyzer(inline_target, this); 314 315 // adjust escape state of actual parameters 316 bool must_record_dependencies = false; 317 for (i = arg_size - 1; i >= 0; i--) { 318 ArgumentMap arg = state.raw_pop(); 319 // Check if callee arg is a caller arg or an allocated object 320 bool allocated = arg.contains_allocated(); 321 if (!(is_argument(arg) || allocated)) 322 continue; 323 for (int j = 0; j < _arg_size; j++) { 324 if (arg.contains(j)) { 325 _arg_modified[j] |= analyzer._arg_modified[i]; 326 } 327 } 328 if (!(is_arg_stack(arg) || allocated)) { 329 // arguments have already been recognized as escaping 330 } else if (analyzer.is_arg_stack(i) && !analyzer.is_arg_returned(i)) { 331 set_method_escape(arg); 332 must_record_dependencies = true; 333 } else { 334 set_global_escape(arg); 335 } 336 } 337 _unknown_modified = _unknown_modified || analyzer.has_non_arg_side_affects(); 338 339 // record dependencies if at least one parameter retained stack-allocatable 340 if (must_record_dependencies) { 341 if (code == Bytecodes::_invokeinterface || 342 (code == Bytecodes::_invokevirtual && !target->is_final_method())) { 343 _dependencies.append(actual_recv); 344 _dependencies.append(inline_target); 345 _dependencies.append(callee_holder); 346 _dependencies.append(target); 347 assert(callee_holder->is_interface() == (code == Bytecodes::_invokeinterface), "sanity"); 348 } 349 _dependencies.appendAll(analyzer.dependencies()); 350 } 351 } else { 352 TRACE_BCEA(1, tty->print_cr("[EA] virtual method %s is not monomorphic.", 353 target->name()->as_utf8())); 354 // conservatively mark all actual parameters as escaping globally 355 for (i = 0; i < arg_size; i++) { 356 ArgumentMap arg = state.raw_pop(); 357 if (!is_argument(arg)) 358 continue; 359 set_modified(arg, OFFSET_ANY, type2size[T_INT]*HeapWordSize); 360 set_global_escape(arg); 361 } 362 _unknown_modified = true; // assume the worst since we don't know the called method 363 } 364 } 365 366 bool BCEscapeAnalyzer::contains(uint arg_set1, uint arg_set2) { 367 return ((~arg_set1) | arg_set2) == 0; 368 } 369 370 371 void BCEscapeAnalyzer::iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors) { 372 373 blk->set_processed(); 374 ciBytecodeStream s(method()); 375 int limit_bci = blk->limit_bci(); 376 bool fall_through = false; 377 ArgumentMap allocated_obj; 378 allocated_obj.add_allocated(); 379 ArgumentMap unknown_obj; 380 unknown_obj.add_unknown(); 381 ArgumentMap empty_map; 382 383 s.reset_to_bci(blk->start_bci()); 384 while (s.next() != ciBytecodeStream::EOBC() && s.cur_bci() < limit_bci) { 385 fall_through = true; 386 switch (s.cur_bc()) { 387 case Bytecodes::_nop: 388 break; 389 case Bytecodes::_aconst_null: 390 state.apush(unknown_obj); 391 break; 392 case Bytecodes::_iconst_m1: 393 case Bytecodes::_iconst_0: 394 case Bytecodes::_iconst_1: 395 case Bytecodes::_iconst_2: 396 case Bytecodes::_iconst_3: 397 case Bytecodes::_iconst_4: 398 case Bytecodes::_iconst_5: 399 case Bytecodes::_fconst_0: 400 case Bytecodes::_fconst_1: 401 case Bytecodes::_fconst_2: 402 case Bytecodes::_bipush: 403 case Bytecodes::_sipush: 404 state.spush(); 405 break; 406 case Bytecodes::_lconst_0: 407 case Bytecodes::_lconst_1: 408 case Bytecodes::_dconst_0: 409 case Bytecodes::_dconst_1: 410 state.lpush(); 411 break; 412 case Bytecodes::_ldc: 413 case Bytecodes::_ldc_w: 414 case Bytecodes::_ldc2_w: 415 { 416 // Avoid calling get_constant() which will try to allocate 417 // unloaded constant. We need only constant's type. 418 int index = s.get_constant_pool_index(); 419 BasicType con_bt = s.get_basic_type_for_constant_at(index); 420 if (con_bt == T_LONG || con_bt == T_DOUBLE) { 421 // Only longs and doubles use 2 stack slots. 422 state.lpush(); 423 } else if (con_bt == T_OBJECT) { 424 state.apush(unknown_obj); 425 } else { 426 state.spush(); 427 } 428 break; 429 } 430 case Bytecodes::_aload: 431 state.apush(state._vars[s.get_index()]); 432 break; 433 case Bytecodes::_iload: 434 case Bytecodes::_fload: 435 case Bytecodes::_iload_0: 436 case Bytecodes::_iload_1: 437 case Bytecodes::_iload_2: 438 case Bytecodes::_iload_3: 439 case Bytecodes::_fload_0: 440 case Bytecodes::_fload_1: 441 case Bytecodes::_fload_2: 442 case Bytecodes::_fload_3: 443 state.spush(); 444 break; 445 case Bytecodes::_lload: 446 case Bytecodes::_dload: 447 case Bytecodes::_lload_0: 448 case Bytecodes::_lload_1: 449 case Bytecodes::_lload_2: 450 case Bytecodes::_lload_3: 451 case Bytecodes::_dload_0: 452 case Bytecodes::_dload_1: 453 case Bytecodes::_dload_2: 454 case Bytecodes::_dload_3: 455 state.lpush(); 456 break; 457 case Bytecodes::_aload_0: 458 state.apush(state._vars[0]); 459 break; 460 case Bytecodes::_aload_1: 461 state.apush(state._vars[1]); 462 break; 463 case Bytecodes::_aload_2: 464 state.apush(state._vars[2]); 465 break; 466 case Bytecodes::_aload_3: 467 state.apush(state._vars[3]); 468 break; 469 case Bytecodes::_iaload: 470 case Bytecodes::_faload: 471 case Bytecodes::_baload: 472 case Bytecodes::_caload: 473 case Bytecodes::_saload: 474 state.spop(); 475 set_method_escape(state.apop()); 476 state.spush(); 477 break; 478 case Bytecodes::_laload: 479 case Bytecodes::_daload: 480 state.spop(); 481 set_method_escape(state.apop()); 482 state.lpush(); 483 break; 484 case Bytecodes::_aaload: 485 { state.spop(); 486 ArgumentMap array = state.apop(); 487 set_method_escape(array); 488 state.apush(unknown_obj); 489 } 490 break; 491 case Bytecodes::_istore: 492 case Bytecodes::_fstore: 493 case Bytecodes::_istore_0: 494 case Bytecodes::_istore_1: 495 case Bytecodes::_istore_2: 496 case Bytecodes::_istore_3: 497 case Bytecodes::_fstore_0: 498 case Bytecodes::_fstore_1: 499 case Bytecodes::_fstore_2: 500 case Bytecodes::_fstore_3: 501 state.spop(); 502 break; 503 case Bytecodes::_lstore: 504 case Bytecodes::_dstore: 505 case Bytecodes::_lstore_0: 506 case Bytecodes::_lstore_1: 507 case Bytecodes::_lstore_2: 508 case Bytecodes::_lstore_3: 509 case Bytecodes::_dstore_0: 510 case Bytecodes::_dstore_1: 511 case Bytecodes::_dstore_2: 512 case Bytecodes::_dstore_3: 513 state.lpop(); 514 break; 515 case Bytecodes::_astore: 516 state._vars[s.get_index()] = state.apop(); 517 break; 518 case Bytecodes::_astore_0: 519 state._vars[0] = state.apop(); 520 break; 521 case Bytecodes::_astore_1: 522 state._vars[1] = state.apop(); 523 break; 524 case Bytecodes::_astore_2: 525 state._vars[2] = state.apop(); 526 break; 527 case Bytecodes::_astore_3: 528 state._vars[3] = state.apop(); 529 break; 530 case Bytecodes::_iastore: 531 case Bytecodes::_fastore: 532 case Bytecodes::_bastore: 533 case Bytecodes::_castore: 534 case Bytecodes::_sastore: 535 { 536 state.spop(); 537 state.spop(); 538 ArgumentMap arr = state.apop(); 539 set_method_escape(arr); 540 set_modified(arr, OFFSET_ANY, type2size[T_INT]*HeapWordSize); 541 break; 542 } 543 case Bytecodes::_lastore: 544 case Bytecodes::_dastore: 545 { 546 state.lpop(); 547 state.spop(); 548 ArgumentMap arr = state.apop(); 549 set_method_escape(arr); 550 set_modified(arr, OFFSET_ANY, type2size[T_LONG]*HeapWordSize); 551 break; 552 } 553 case Bytecodes::_aastore: 554 { 555 set_global_escape(state.apop()); 556 state.spop(); 557 ArgumentMap arr = state.apop(); 558 // If the array is flattened, a larger part of it is modified than 559 // the size of a reference. However, if OFFSET_ANY is given as 560 // parameter to set_modified(), size is not taken into account. 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 (is_reference_type(field_type)) { 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 (is_reference_type(field_type)) { 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 case Bytecodes::_aconst_init: 946 state.apush(allocated_obj); 947 break; 948 case Bytecodes::_withfield: { 949 bool will_link; 950 ciField* field = s.get_field(will_link); 951 BasicType field_type = field->type()->basic_type(); 952 if (field_type == T_OBJECT || field_type == T_ARRAY) { 953 set_global_escape(state.apop()); 954 } else if (type2size[field_type] == 1) { 955 state.spop(); 956 } else { 957 state.lpop(); 958 } 959 set_method_escape(state.apop()); 960 state.apush(allocated_obj); 961 break; 962 } 963 case Bytecodes::_newarray: 964 case Bytecodes::_anewarray: 965 state.spop(); 966 state.apush(allocated_obj); 967 break; 968 case Bytecodes::_multianewarray: 969 { int i = s.cur_bcp()[3]; 970 while (i-- > 0) state.spop(); 971 state.apush(allocated_obj); 972 } 973 break; 974 case Bytecodes::_arraylength: 975 set_method_escape(state.apop()); 976 state.spush(); 977 break; 978 case Bytecodes::_athrow: 979 set_global_escape(state.apop()); 980 fall_through = false; 981 break; 982 case Bytecodes::_checkcast: 983 { ArgumentMap obj = state.apop(); 984 set_method_escape(obj); 985 state.apush(obj); 986 } 987 break; 988 case Bytecodes::_instanceof: 989 set_method_escape(state.apop()); 990 state.spush(); 991 break; 992 case Bytecodes::_monitorenter: 993 case Bytecodes::_monitorexit: 994 state.apop(); 995 break; 996 case Bytecodes::_wide: 997 ShouldNotReachHere(); 998 break; 999 case Bytecodes::_ifnull: 1000 case Bytecodes::_ifnonnull: 1001 { 1002 set_method_escape(state.apop()); 1003 int dest_bci = s.get_dest(); 1004 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 1005 assert(s.next_bci() == limit_bci, "branch must end block"); 1006 successors.push(_methodBlocks->block_containing(dest_bci)); 1007 break; 1008 } 1009 case Bytecodes::_goto_w: 1010 { 1011 int dest_bci = s.get_far_dest(); 1012 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 1013 assert(s.next_bci() == limit_bci, "branch must end block"); 1014 successors.push(_methodBlocks->block_containing(dest_bci)); 1015 fall_through = false; 1016 break; 1017 } 1018 case Bytecodes::_jsr_w: 1019 { 1020 int dest_bci = s.get_far_dest(); 1021 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block"); 1022 assert(s.next_bci() == limit_bci, "branch must end block"); 1023 state.apush(empty_map); 1024 successors.push(_methodBlocks->block_containing(dest_bci)); 1025 fall_through = false; 1026 break; 1027 } 1028 case Bytecodes::_breakpoint: 1029 break; 1030 default: 1031 ShouldNotReachHere(); 1032 break; 1033 } 1034 1035 } 1036 if (fall_through) { 1037 int fall_through_bci = s.cur_bci(); 1038 if (fall_through_bci < _method->code_size()) { 1039 assert(_methodBlocks->is_block_start(fall_through_bci), "must fall through to block start."); 1040 successors.push(_methodBlocks->block_containing(fall_through_bci)); 1041 } 1042 } 1043 } 1044 1045 void BCEscapeAnalyzer::merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state) { 1046 StateInfo *d_state = blockstates + dest->index(); 1047 int nlocals = _method->max_locals(); 1048 1049 // exceptions may cause transfer of control to handlers in the middle of a 1050 // block, so we don't merge the incoming state of exception handlers 1051 if (dest->is_handler()) 1052 return; 1053 if (!d_state->_initialized ) { 1054 // destination not initialized, just copy 1055 for (int i = 0; i < nlocals; i++) { 1056 d_state->_vars[i] = s_state->_vars[i]; 1057 } 1058 for (int i = 0; i < s_state->_stack_height; i++) { 1059 d_state->_stack[i] = s_state->_stack[i]; 1060 } 1061 d_state->_stack_height = s_state->_stack_height; 1062 d_state->_max_stack = s_state->_max_stack; 1063 d_state->_initialized = true; 1064 } else if (!dest->processed()) { 1065 // we have not yet walked the bytecodes of dest, we can merge 1066 // the states 1067 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match"); 1068 for (int i = 0; i < nlocals; i++) { 1069 d_state->_vars[i].set_union(s_state->_vars[i]); 1070 } 1071 for (int i = 0; i < s_state->_stack_height; i++) { 1072 d_state->_stack[i].set_union(s_state->_stack[i]); 1073 } 1074 } else { 1075 // the bytecodes of dest have already been processed, mark any 1076 // arguments in the source state which are not in the dest state 1077 // as global escape. 1078 // Future refinement: we only need to mark these variable to the 1079 // maximum escape of any variables in dest state 1080 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match"); 1081 ArgumentMap extra_vars; 1082 for (int i = 0; i < nlocals; i++) { 1083 ArgumentMap t; 1084 t = s_state->_vars[i]; 1085 t.set_difference(d_state->_vars[i]); 1086 extra_vars.set_union(t); 1087 } 1088 for (int i = 0; i < s_state->_stack_height; i++) { 1089 ArgumentMap t; 1090 //extra_vars |= !d_state->_vars[i] & s_state->_vars[i]; 1091 t.clear(); 1092 t = s_state->_stack[i]; 1093 t.set_difference(d_state->_stack[i]); 1094 extra_vars.set_union(t); 1095 } 1096 set_global_escape(extra_vars, true); 1097 } 1098 } 1099 1100 void BCEscapeAnalyzer::iterate_blocks(Arena *arena) { 1101 int numblocks = _methodBlocks->num_blocks(); 1102 int stkSize = _method->max_stack(); 1103 int numLocals = _method->max_locals(); 1104 StateInfo state; 1105 1106 int datacount = (numblocks + 1) * (stkSize + numLocals); 1107 int datasize = datacount * sizeof(ArgumentMap); 1108 StateInfo *blockstates = (StateInfo *) arena->Amalloc(numblocks * sizeof(StateInfo)); 1109 ArgumentMap *statedata = (ArgumentMap *) arena->Amalloc(datasize); 1110 for (int i = 0; i < datacount; i++) ::new ((void*)&statedata[i]) ArgumentMap(); 1111 ArgumentMap *dp = statedata; 1112 state._vars = dp; 1113 dp += numLocals; 1114 state._stack = dp; 1115 dp += stkSize; 1116 state._initialized = false; 1117 state._max_stack = stkSize; 1118 for (int i = 0; i < numblocks; i++) { 1119 blockstates[i]._vars = dp; 1120 dp += numLocals; 1121 blockstates[i]._stack = dp; 1122 dp += stkSize; 1123 blockstates[i]._initialized = false; 1124 blockstates[i]._stack_height = 0; 1125 blockstates[i]._max_stack = stkSize; 1126 } 1127 GrowableArray<ciBlock *> worklist(arena, numblocks / 4, 0, NULL); 1128 GrowableArray<ciBlock *> successors(arena, 4, 0, NULL); 1129 1130 _methodBlocks->clear_processed(); 1131 1132 // initialize block 0 state from method signature 1133 ArgumentMap allVars; // all oop arguments to method 1134 ciSignature* sig = method()->signature(); 1135 int j = 0; 1136 ciBlock* first_blk = _methodBlocks->block_containing(0); 1137 int fb_i = first_blk->index(); 1138 if (!method()->is_static()) { 1139 // record information for "this" 1140 blockstates[fb_i]._vars[j].set(j); 1141 allVars.add(j); 1142 j++; 1143 } 1144 for (int i = 0; i < sig->count(); i++) { 1145 ciType* t = sig->type_at(i); 1146 if (!t->is_primitive_type()) { 1147 blockstates[fb_i]._vars[j].set(j); 1148 allVars.add(j); 1149 } 1150 j += t->size(); 1151 } 1152 blockstates[fb_i]._initialized = true; 1153 assert(j == _arg_size, "just checking"); 1154 1155 ArgumentMap unknown_map; 1156 unknown_map.add_unknown(); 1157 1158 worklist.push(first_blk); 1159 while(worklist.length() > 0) { 1160 ciBlock *blk = worklist.pop(); 1161 StateInfo *blkState = blockstates + blk->index(); 1162 if (blk->is_handler() || blk->is_ret_target()) { 1163 // for an exception handler or a target of a ret instruction, we assume the worst case, 1164 // that any variable could contain any argument 1165 for (int i = 0; i < numLocals; i++) { 1166 state._vars[i] = allVars; 1167 } 1168 if (blk->is_handler()) { 1169 state._stack_height = 1; 1170 } else { 1171 state._stack_height = blkState->_stack_height; 1172 } 1173 for (int i = 0; i < state._stack_height; i++) { 1174 // ??? should this be unknown_map ??? 1175 state._stack[i] = allVars; 1176 } 1177 } else { 1178 for (int i = 0; i < numLocals; i++) { 1179 state._vars[i] = blkState->_vars[i]; 1180 } 1181 for (int i = 0; i < blkState->_stack_height; i++) { 1182 state._stack[i] = blkState->_stack[i]; 1183 } 1184 state._stack_height = blkState->_stack_height; 1185 } 1186 iterate_one_block(blk, state, successors); 1187 // if this block has any exception handlers, push them 1188 // onto successor list 1189 if (blk->has_handler()) { 1190 DEBUG_ONLY(int handler_count = 0;) 1191 int blk_start = blk->start_bci(); 1192 int blk_end = blk->limit_bci(); 1193 for (int i = 0; i < numblocks; i++) { 1194 ciBlock *b = _methodBlocks->block(i); 1195 if (b->is_handler()) { 1196 int ex_start = b->ex_start_bci(); 1197 int ex_end = b->ex_limit_bci(); 1198 if ((ex_start >= blk_start && ex_start < blk_end) || 1199 (ex_end > blk_start && ex_end <= blk_end)) { 1200 successors.push(b); 1201 } 1202 DEBUG_ONLY(handler_count++;) 1203 } 1204 } 1205 assert(handler_count > 0, "must find at least one handler"); 1206 } 1207 // merge computed variable state with successors 1208 while(successors.length() > 0) { 1209 ciBlock *succ = successors.pop(); 1210 merge_block_states(blockstates, succ, &state); 1211 if (!succ->processed()) 1212 worklist.push(succ); 1213 } 1214 } 1215 } 1216 1217 void BCEscapeAnalyzer::do_analysis() { 1218 Arena* arena = CURRENT_ENV->arena(); 1219 // identify basic blocks 1220 _methodBlocks = _method->get_method_blocks(); 1221 1222 iterate_blocks(arena); 1223 } 1224 1225 vmIntrinsicID BCEscapeAnalyzer::known_intrinsic() { 1226 vmIntrinsicID iid = method()->intrinsic_id(); 1227 if (iid == vmIntrinsics::_getClass || 1228 iid == vmIntrinsics::_hashCode) { 1229 return iid; 1230 } else { 1231 return vmIntrinsics::_none; 1232 } 1233 } 1234 1235 void BCEscapeAnalyzer::compute_escape_for_intrinsic(vmIntrinsicID iid) { 1236 switch (iid) { 1237 case vmIntrinsics::_getClass: 1238 _return_local = false; 1239 _return_allocated = false; 1240 break; 1241 case vmIntrinsics::_hashCode: 1242 // initialized state is correct 1243 break; 1244 default: 1245 assert(false, "unexpected intrinsic"); 1246 } 1247 } 1248 1249 void BCEscapeAnalyzer::initialize() { 1250 int i; 1251 1252 // clear escape information (method may have been deoptimized) 1253 methodData()->clear_escape_info(); 1254 1255 // initialize escape state of object parameters 1256 ciSignature* sig = method()->signature(); 1257 int j = 0; 1258 if (!method()->is_static()) { 1259 _arg_local.set(0); 1260 _arg_stack.set(0); 1261 j++; 1262 } 1263 for (i = 0; i < sig->count(); i++) { 1264 ciType* t = sig->type_at(i); 1265 if (!t->is_primitive_type()) { 1266 _arg_local.set(j); 1267 _arg_stack.set(j); 1268 } 1269 j += t->size(); 1270 } 1271 assert(j == _arg_size, "just checking"); 1272 1273 // start with optimistic assumption 1274 ciType *rt = _method->return_type(); 1275 if (rt->is_primitive_type()) { 1276 _return_local = false; 1277 _return_allocated = false; 1278 } else { 1279 _return_local = true; 1280 _return_allocated = true; 1281 } 1282 _allocated_escapes = false; 1283 _unknown_modified = false; 1284 } 1285 1286 void BCEscapeAnalyzer::clear_escape_info() { 1287 ciSignature* sig = method()->signature(); 1288 int arg_count = sig->count(); 1289 ArgumentMap var; 1290 if (!method()->is_static()) { 1291 arg_count++; // allow for "this" 1292 } 1293 for (int i = 0; i < arg_count; i++) { 1294 set_arg_modified(i, OFFSET_ANY, 4); 1295 var.clear(); 1296 var.set(i); 1297 set_modified(var, OFFSET_ANY, 4); 1298 set_global_escape(var); 1299 } 1300 _arg_local.clear(); 1301 _arg_stack.clear(); 1302 _arg_returned.clear(); 1303 _return_local = false; 1304 _return_allocated = false; 1305 _allocated_escapes = true; 1306 _unknown_modified = true; 1307 } 1308 1309 1310 void BCEscapeAnalyzer::compute_escape_info() { 1311 int i; 1312 assert(!methodData()->has_escape_info(), "do not overwrite escape info"); 1313 1314 vmIntrinsicID iid = known_intrinsic(); 1315 1316 // check if method can be analyzed 1317 if (iid == vmIntrinsics::_none && (method()->is_abstract() || method()->is_native() || !method()->holder()->is_initialized() 1318 || _level > MaxBCEAEstimateLevel 1319 || method()->code_size() > MaxBCEAEstimateSize)) { 1320 if (BCEATraceLevel >= 1) { 1321 tty->print("Skipping method because: "); 1322 if (method()->is_abstract()) 1323 tty->print_cr("method is abstract."); 1324 else if (method()->is_native()) 1325 tty->print_cr("method is native."); 1326 else if (!method()->holder()->is_initialized()) 1327 tty->print_cr("class of method is not initialized."); 1328 else if (_level > MaxBCEAEstimateLevel) 1329 tty->print_cr("level (%d) exceeds MaxBCEAEstimateLevel (%d).", 1330 _level, (int) MaxBCEAEstimateLevel); 1331 else if (method()->code_size() > MaxBCEAEstimateSize) 1332 tty->print_cr("code size (%d) exceeds MaxBCEAEstimateSize (%d).", 1333 method()->code_size(), (int) MaxBCEAEstimateSize); 1334 else 1335 ShouldNotReachHere(); 1336 } 1337 clear_escape_info(); 1338 1339 return; 1340 } 1341 1342 if (BCEATraceLevel >= 1) { 1343 tty->print("[EA] estimating escape information for"); 1344 if (iid != vmIntrinsics::_none) 1345 tty->print(" intrinsic"); 1346 method()->print_short_name(); 1347 tty->print_cr(" (%d bytes)", method()->code_size()); 1348 } 1349 1350 initialize(); 1351 1352 // Do not scan method if it has no object parameters and 1353 // does not returns an object (_return_allocated is set in initialize()). 1354 if (_arg_local.is_empty() && !_return_allocated) { 1355 // Clear all info since method's bytecode was not analysed and 1356 // set pessimistic escape information. 1357 clear_escape_info(); 1358 methodData()->set_eflag(MethodData::allocated_escapes); 1359 methodData()->set_eflag(MethodData::unknown_modified); 1360 methodData()->set_eflag(MethodData::estimated); 1361 return; 1362 } 1363 1364 if (iid != vmIntrinsics::_none) 1365 compute_escape_for_intrinsic(iid); 1366 else { 1367 do_analysis(); 1368 } 1369 1370 // don't store interprocedural escape information if it introduces 1371 // dependencies or if method data is empty 1372 // 1373 if (!has_dependencies() && !methodData()->is_empty()) { 1374 for (i = 0; i < _arg_size; i++) { 1375 if (_arg_local.test(i)) { 1376 assert(_arg_stack.test(i), "inconsistent escape info"); 1377 methodData()->set_arg_local(i); 1378 methodData()->set_arg_stack(i); 1379 } else if (_arg_stack.test(i)) { 1380 methodData()->set_arg_stack(i); 1381 } 1382 if (_arg_returned.test(i)) { 1383 methodData()->set_arg_returned(i); 1384 } 1385 methodData()->set_arg_modified(i, _arg_modified[i]); 1386 } 1387 if (_return_local) { 1388 methodData()->set_eflag(MethodData::return_local); 1389 } 1390 if (_return_allocated) { 1391 methodData()->set_eflag(MethodData::return_allocated); 1392 } 1393 if (_allocated_escapes) { 1394 methodData()->set_eflag(MethodData::allocated_escapes); 1395 } 1396 if (_unknown_modified) { 1397 methodData()->set_eflag(MethodData::unknown_modified); 1398 } 1399 methodData()->set_eflag(MethodData::estimated); 1400 } 1401 } 1402 1403 void BCEscapeAnalyzer::read_escape_info() { 1404 assert(methodData()->has_escape_info(), "no escape info available"); 1405 1406 // read escape information from method descriptor 1407 for (int i = 0; i < _arg_size; i++) { 1408 if (methodData()->is_arg_local(i)) 1409 _arg_local.set(i); 1410 if (methodData()->is_arg_stack(i)) 1411 _arg_stack.set(i); 1412 if (methodData()->is_arg_returned(i)) 1413 _arg_returned.set(i); 1414 _arg_modified[i] = methodData()->arg_modified(i); 1415 } 1416 _return_local = methodData()->eflag_set(MethodData::return_local); 1417 _return_allocated = methodData()->eflag_set(MethodData::return_allocated); 1418 _allocated_escapes = methodData()->eflag_set(MethodData::allocated_escapes); 1419 _unknown_modified = methodData()->eflag_set(MethodData::unknown_modified); 1420 1421 } 1422 1423 #ifndef PRODUCT 1424 void BCEscapeAnalyzer::dump() { 1425 tty->print("[EA] estimated escape information for"); 1426 method()->print_short_name(); 1427 tty->print_cr(has_dependencies() ? " (not stored)" : ""); 1428 tty->print(" non-escaping args: "); 1429 _arg_local.print(); 1430 tty->print(" stack-allocatable args: "); 1431 _arg_stack.print(); 1432 if (_return_local) { 1433 tty->print(" returned args: "); 1434 _arg_returned.print(); 1435 } else if (is_return_allocated()) { 1436 tty->print_cr(" return allocated value"); 1437 } else { 1438 tty->print_cr(" return non-local value"); 1439 } 1440 tty->print(" modified args: "); 1441 for (int i = 0; i < _arg_size; i++) { 1442 if (_arg_modified[i] == 0) 1443 tty->print(" 0"); 1444 else 1445 tty->print(" 0x%x", _arg_modified[i]); 1446 } 1447 tty->cr(); 1448 tty->print(" flags: "); 1449 if (_return_allocated) 1450 tty->print(" return_allocated"); 1451 if (_allocated_escapes) 1452 tty->print(" allocated_escapes"); 1453 if (_unknown_modified) 1454 tty->print(" unknown_modified"); 1455 tty->cr(); 1456 } 1457 #endif 1458 1459 BCEscapeAnalyzer::BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent) 1460 : _arena(CURRENT_ENV->arena()) 1461 , _conservative(method == NULL || !EstimateArgEscape) 1462 , _method(method) 1463 , _methodData(method ? method->method_data() : NULL) 1464 , _arg_size(method ? method->arg_size() : 0) 1465 , _arg_local(_arena) 1466 , _arg_stack(_arena) 1467 , _arg_returned(_arena) 1468 , _return_local(false) 1469 , _return_allocated(false) 1470 , _allocated_escapes(false) 1471 , _unknown_modified(false) 1472 , _dependencies(_arena, 4, 0, NULL) 1473 , _parent(parent) 1474 , _level(parent == NULL ? 0 : parent->level() + 1) { 1475 if (!_conservative) { 1476 _arg_local.clear(); 1477 _arg_stack.clear(); 1478 _arg_returned.clear(); 1479 Arena* arena = CURRENT_ENV->arena(); 1480 _arg_modified = (uint *) arena->Amalloc(_arg_size * sizeof(uint)); 1481 Copy::zero_to_bytes(_arg_modified, _arg_size * sizeof(uint)); 1482 1483 if (methodData() == NULL) 1484 return; 1485 if (methodData()->has_escape_info()) { 1486 TRACE_BCEA(2, tty->print_cr("[EA] Reading previous results for %s.%s", 1487 method->holder()->name()->as_utf8(), 1488 method->name()->as_utf8())); 1489 read_escape_info(); 1490 } else { 1491 TRACE_BCEA(2, tty->print_cr("[EA] computing results for %s.%s", 1492 method->holder()->name()->as_utf8(), 1493 method->name()->as_utf8())); 1494 1495 compute_escape_info(); 1496 methodData()->update_escape_info(); 1497 } 1498 #ifndef PRODUCT 1499 if (BCEATraceLevel >= 3) { 1500 // dump escape information 1501 dump(); 1502 } 1503 #endif 1504 } 1505 } 1506 1507 void BCEscapeAnalyzer::copy_dependencies(Dependencies *deps) { 1508 if (ciEnv::current()->jvmti_can_hotswap_or_post_breakpoint()) { 1509 // Also record evol dependencies so redefinition of the 1510 // callee will trigger recompilation. 1511 deps->assert_evol_method(method()); 1512 } 1513 for (int i = 0; i < _dependencies.length(); i+=4) { 1514 ciKlass* recv_klass = _dependencies.at(i+0)->as_klass(); 1515 ciMethod* target = _dependencies.at(i+1)->as_method(); 1516 ciKlass* resolved_klass = _dependencies.at(i+2)->as_klass(); 1517 ciMethod* resolved_method = _dependencies.at(i+3)->as_method(); 1518 deps->assert_unique_concrete_method(recv_klass, target, resolved_klass, resolved_method); 1519 } 1520 }