1 /* 2 * Copyright (c) 2000, 2018, 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/ciConstant.hpp" 27 #include "ci/ciField.hpp" 28 #include "ci/ciMethod.hpp" 29 #include "ci/ciMethodData.hpp" 30 #include "ci/ciObjArrayKlass.hpp" 31 #include "ci/ciStreams.hpp" 32 #include "ci/ciTypeArrayKlass.hpp" 33 #include "ci/ciTypeFlow.hpp" 34 #include "ci/ciValueKlass.hpp" 35 #include "compiler/compileLog.hpp" 36 #include "interpreter/bytecode.hpp" 37 #include "interpreter/bytecodes.hpp" 38 #include "memory/allocation.inline.hpp" 39 #include "memory/resourceArea.hpp" 40 #include "oops/oop.inline.hpp" 41 #include "opto/compile.hpp" 42 #include "opto/node.hpp" 43 #include "runtime/deoptimization.hpp" 44 #include "utilities/growableArray.hpp" 45 46 // ciTypeFlow::JsrSet 47 // 48 // A JsrSet represents some set of JsrRecords. This class 49 // is used to record a set of all jsr routines which we permit 50 // execution to return (ret) from. 51 // 52 // During abstract interpretation, JsrSets are used to determine 53 // whether two paths which reach a given block are unique, and 54 // should be cloned apart, or are compatible, and should merge 55 // together. 56 57 // ------------------------------------------------------------------ 58 // ciTypeFlow::JsrSet::JsrSet 59 ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) { 60 if (arena != NULL) { 61 // Allocate growable array in Arena. 62 _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL); 63 } else { 64 // Allocate growable array in current ResourceArea. 65 _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false); 66 } 67 } 68 69 // ------------------------------------------------------------------ 70 // ciTypeFlow::JsrSet::copy_into 71 void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) { 72 int len = size(); 73 jsrs->_set->clear(); 74 for (int i = 0; i < len; i++) { 75 jsrs->_set->append(_set->at(i)); 76 } 77 } 78 79 // ------------------------------------------------------------------ 80 // ciTypeFlow::JsrSet::is_compatible_with 81 // 82 // !!!! MISGIVINGS ABOUT THIS... disregard 83 // 84 // Is this JsrSet compatible with some other JsrSet? 85 // 86 // In set-theoretic terms, a JsrSet can be viewed as a partial function 87 // from entry addresses to return addresses. Two JsrSets A and B are 88 // compatible iff 89 // 90 // For any x, 91 // A(x) defined and B(x) defined implies A(x) == B(x) 92 // 93 // Less formally, two JsrSets are compatible when they have identical 94 // return addresses for any entry addresses they share in common. 95 bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) { 96 // Walk through both sets in parallel. If the same entry address 97 // appears in both sets, then the return address must match for 98 // the sets to be compatible. 99 int size1 = size(); 100 int size2 = other->size(); 101 102 // Special case. If nothing is on the jsr stack, then there can 103 // be no ret. 104 if (size2 == 0) { 105 return true; 106 } else if (size1 != size2) { 107 return false; 108 } else { 109 for (int i = 0; i < size1; i++) { 110 JsrRecord* record1 = record_at(i); 111 JsrRecord* record2 = other->record_at(i); 112 if (record1->entry_address() != record2->entry_address() || 113 record1->return_address() != record2->return_address()) { 114 return false; 115 } 116 } 117 return true; 118 } 119 120 #if 0 121 int pos1 = 0; 122 int pos2 = 0; 123 int size1 = size(); 124 int size2 = other->size(); 125 while (pos1 < size1 && pos2 < size2) { 126 JsrRecord* record1 = record_at(pos1); 127 JsrRecord* record2 = other->record_at(pos2); 128 int entry1 = record1->entry_address(); 129 int entry2 = record2->entry_address(); 130 if (entry1 < entry2) { 131 pos1++; 132 } else if (entry1 > entry2) { 133 pos2++; 134 } else { 135 if (record1->return_address() == record2->return_address()) { 136 pos1++; 137 pos2++; 138 } else { 139 // These two JsrSets are incompatible. 140 return false; 141 } 142 } 143 } 144 // The two JsrSets agree. 145 return true; 146 #endif 147 } 148 149 // ------------------------------------------------------------------ 150 // ciTypeFlow::JsrSet::insert_jsr_record 151 // 152 // Insert the given JsrRecord into the JsrSet, maintaining the order 153 // of the set and replacing any element with the same entry address. 154 void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) { 155 int len = size(); 156 int entry = record->entry_address(); 157 int pos = 0; 158 for ( ; pos < len; pos++) { 159 JsrRecord* current = record_at(pos); 160 if (entry == current->entry_address()) { 161 // Stomp over this entry. 162 _set->at_put(pos, record); 163 assert(size() == len, "must be same size"); 164 return; 165 } else if (entry < current->entry_address()) { 166 break; 167 } 168 } 169 170 // Insert the record into the list. 171 JsrRecord* swap = record; 172 JsrRecord* temp = NULL; 173 for ( ; pos < len; pos++) { 174 temp = _set->at(pos); 175 _set->at_put(pos, swap); 176 swap = temp; 177 } 178 _set->append(swap); 179 assert(size() == len+1, "must be larger"); 180 } 181 182 // ------------------------------------------------------------------ 183 // ciTypeFlow::JsrSet::remove_jsr_record 184 // 185 // Remove the JsrRecord with the given return address from the JsrSet. 186 void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) { 187 int len = size(); 188 for (int i = 0; i < len; i++) { 189 if (record_at(i)->return_address() == return_address) { 190 // We have found the proper entry. Remove it from the 191 // JsrSet and exit. 192 for (int j = i+1; j < len ; j++) { 193 _set->at_put(j-1, _set->at(j)); 194 } 195 _set->trunc_to(len-1); 196 assert(size() == len-1, "must be smaller"); 197 return; 198 } 199 } 200 assert(false, "verify: returning from invalid subroutine"); 201 } 202 203 // ------------------------------------------------------------------ 204 // ciTypeFlow::JsrSet::apply_control 205 // 206 // Apply the effect of a control-flow bytecode on the JsrSet. The 207 // only bytecodes that modify the JsrSet are jsr and ret. 208 void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer, 209 ciBytecodeStream* str, 210 ciTypeFlow::StateVector* state) { 211 Bytecodes::Code code = str->cur_bc(); 212 if (code == Bytecodes::_jsr) { 213 JsrRecord* record = 214 analyzer->make_jsr_record(str->get_dest(), str->next_bci()); 215 insert_jsr_record(record); 216 } else if (code == Bytecodes::_jsr_w) { 217 JsrRecord* record = 218 analyzer->make_jsr_record(str->get_far_dest(), str->next_bci()); 219 insert_jsr_record(record); 220 } else if (code == Bytecodes::_ret) { 221 Cell local = state->local(str->get_index()); 222 ciType* return_address = state->type_at(local); 223 assert(return_address->is_return_address(), "verify: wrong type"); 224 if (size() == 0) { 225 // Ret-state underflow: Hit a ret w/o any previous jsrs. Bail out. 226 // This can happen when a loop is inside a finally clause (4614060). 227 analyzer->record_failure("OSR in finally clause"); 228 return; 229 } 230 remove_jsr_record(return_address->as_return_address()->bci()); 231 } 232 } 233 234 #ifndef PRODUCT 235 // ------------------------------------------------------------------ 236 // ciTypeFlow::JsrSet::print_on 237 void ciTypeFlow::JsrSet::print_on(outputStream* st) const { 238 st->print("{ "); 239 int num_elements = size(); 240 if (num_elements > 0) { 241 int i = 0; 242 for( ; i < num_elements - 1; i++) { 243 _set->at(i)->print_on(st); 244 st->print(", "); 245 } 246 _set->at(i)->print_on(st); 247 st->print(" "); 248 } 249 st->print("}"); 250 } 251 #endif 252 253 // ciTypeFlow::StateVector 254 // 255 // A StateVector summarizes the type information at some point in 256 // the program. 257 258 // ------------------------------------------------------------------ 259 // ciTypeFlow::StateVector::type_meet 260 // 261 // Meet two types. 262 // 263 // The semi-lattice of types use by this analysis are modeled on those 264 // of the verifier. The lattice is as follows: 265 // 266 // top_type() >= all non-extremal types >= bottom_type 267 // and 268 // Every primitive type is comparable only with itself. The meet of 269 // reference types is determined by their kind: instance class, 270 // interface, or array class. The meet of two types of the same 271 // kind is their least common ancestor. The meet of two types of 272 // different kinds is always java.lang.Object. 273 ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) { 274 assert(t1 != t2, "checked in caller"); 275 276 if (t1->equals(top_type())) { 277 return t2; 278 } else if (t2->equals(top_type())) { 279 return t1; 280 } else if (t1->is_primitive_type() || t2->is_primitive_type()) { 281 // Special case null_type. null_type meet any reference type T 282 // is T. null_type meet null_type is null_type. 283 if (t1->equals(null_type())) { 284 if (!t2->is_primitive_type() || t2->equals(null_type())) { 285 return t2; 286 } 287 } else if (t2->equals(null_type())) { 288 if (!t1->is_primitive_type()) { 289 return t1; 290 } 291 } 292 293 // At least one of the two types is a non-top primitive type. 294 // The other type is not equal to it. Fall to bottom. 295 return bottom_type(); 296 } 297 298 // Unwrap the types after gathering nullness information 299 bool never_null1 = t1->is_never_null(); 300 bool never_null2 = t2->is_never_null(); 301 t1 = t1->unwrap(); 302 t2 = t2->unwrap(); 303 304 // Both types are non-top non-primitive types. That is, 305 // both types are either instanceKlasses or arrayKlasses. 306 ciKlass* object_klass = analyzer->env()->Object_klass(); 307 ciKlass* k1 = t1->as_klass(); 308 ciKlass* k2 = t2->as_klass(); 309 if (k1->equals(object_klass) || k2->equals(object_klass)) { 310 return object_klass; 311 } else if (!k1->is_loaded() || !k2->is_loaded()) { 312 // Unloaded classes fall to java.lang.Object at a merge. 313 return object_klass; 314 } else if (k1->is_interface() != k2->is_interface()) { 315 // When an interface meets a non-interface, we get Object; 316 // This is what the verifier does. 317 return object_klass; 318 } else if (k1->is_array_klass() || k2->is_array_klass()) { 319 // When an array meets a non-array, we get Object. 320 // When objArray meets typeArray, we also get Object. 321 // And when typeArray meets different typeArray, we again get Object. 322 // But when objArray meets objArray, we look carefully at element types. 323 if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) { 324 // Meet the element types, then construct the corresponding array type. 325 ciKlass* elem1 = k1->as_obj_array_klass()->element_klass(); 326 ciKlass* elem2 = k2->as_obj_array_klass()->element_klass(); 327 ciKlass* elem = type_meet_internal(elem1, elem2, analyzer)->as_klass(); 328 // Do an easy shortcut if one type is a super of the other. 329 if (elem == elem1) { 330 assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK"); 331 return k1; 332 } else if (elem == elem2) { 333 assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK"); 334 return k2; 335 } else { 336 return ciObjArrayKlass::make(elem); 337 } 338 } else if (k1->is_value_array_klass() || k2->is_value_array_klass()) { 339 ciKlass* elem1 = k1->as_array_klass()->element_klass(); 340 ciKlass* elem2 = k2->as_array_klass()->element_klass(); 341 ciKlass* elem = type_meet_internal(elem1, elem2, analyzer)->as_klass(); 342 return ciArrayKlass::make(elem); 343 } else { 344 return object_klass; 345 } 346 } else { 347 // Must be two plain old instance klasses. 348 assert(k1->is_instance_klass(), "previous cases handle non-instances"); 349 assert(k2->is_instance_klass(), "previous cases handle non-instances"); 350 ciType* result = k1->least_common_ancestor(k2); 351 if (never_null1 && never_null2 && result->is_valuetype()) { 352 // Both value types are never null, mark the result as never null 353 result = analyzer->mark_as_never_null(result); 354 } 355 return result; 356 } 357 } 358 359 360 // ------------------------------------------------------------------ 361 // ciTypeFlow::StateVector::StateVector 362 // 363 // Build a new state vector 364 ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) { 365 _outer = analyzer; 366 _stack_size = -1; 367 _monitor_count = -1; 368 // Allocate the _types array 369 int max_cells = analyzer->max_cells(); 370 _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells); 371 for (int i=0; i<max_cells; i++) { 372 _types[i] = top_type(); 373 } 374 _trap_bci = -1; 375 _trap_index = 0; 376 _def_locals.clear(); 377 } 378 379 380 // ------------------------------------------------------------------ 381 // ciTypeFlow::get_start_state 382 // 383 // Set this vector to the method entry state. 384 const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() { 385 StateVector* state = new StateVector(this); 386 if (is_osr_flow()) { 387 ciTypeFlow* non_osr_flow = method()->get_flow_analysis(); 388 if (non_osr_flow->failing()) { 389 record_failure(non_osr_flow->failure_reason()); 390 return NULL; 391 } 392 JsrSet* jsrs = new JsrSet(NULL, 16); 393 Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs); 394 if (non_osr_block == NULL) { 395 record_failure("cannot reach OSR point"); 396 return NULL; 397 } 398 // load up the non-OSR state at this point 399 non_osr_block->copy_state_into(state); 400 int non_osr_start = non_osr_block->start(); 401 if (non_osr_start != start_bci()) { 402 // must flow forward from it 403 if (CITraceTypeFlow) { 404 tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start); 405 } 406 Block* block = block_at(non_osr_start, jsrs); 407 assert(block->limit() == start_bci(), "must flow forward to start"); 408 flow_block(block, state, jsrs); 409 } 410 return state; 411 // Note: The code below would be an incorrect for an OSR flow, 412 // even if it were possible for an OSR entry point to be at bci zero. 413 } 414 // "Push" the method signature into the first few locals. 415 state->set_stack_size(-max_locals()); 416 if (!method()->is_static()) { 417 ciType* holder = method()->holder(); 418 if (holder->is_valuetype()) { 419 // The receiver is never null 420 holder = mark_as_never_null(holder); 421 } 422 state->push(holder); 423 assert(state->tos() == state->local(0), ""); 424 } 425 for (ciSignatureStream str(method()->signature()); 426 !str.at_return_type(); 427 str.next()) { 428 ciType* arg = str.type(); 429 if (str.is_never_null()) { 430 arg = mark_as_never_null(arg); 431 } 432 state->push_translate(arg); 433 } 434 // Set the rest of the locals to bottom. 435 Cell cell = state->next_cell(state->tos()); 436 state->set_stack_size(0); 437 int limit = state->limit_cell(); 438 for (; cell < limit; cell = state->next_cell(cell)) { 439 state->set_type_at(cell, state->bottom_type()); 440 } 441 // Lock an object, if necessary. 442 state->set_monitor_count(method()->is_synchronized() ? 1 : 0); 443 return state; 444 } 445 446 // ------------------------------------------------------------------ 447 // ciTypeFlow::StateVector::copy_into 448 // 449 // Copy our value into some other StateVector 450 void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy) 451 const { 452 copy->set_stack_size(stack_size()); 453 copy->set_monitor_count(monitor_count()); 454 Cell limit = limit_cell(); 455 for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 456 copy->set_type_at(c, type_at(c)); 457 } 458 } 459 460 // ------------------------------------------------------------------ 461 // ciTypeFlow::StateVector::meet 462 // 463 // Meets this StateVector with another, destructively modifying this 464 // one. Returns true if any modification takes place. 465 bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) { 466 if (monitor_count() == -1) { 467 set_monitor_count(incoming->monitor_count()); 468 } 469 assert(monitor_count() == incoming->monitor_count(), "monitors must match"); 470 471 if (stack_size() == -1) { 472 set_stack_size(incoming->stack_size()); 473 Cell limit = limit_cell(); 474 #ifdef ASSERT 475 { for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 476 assert(type_at(c) == top_type(), ""); 477 } } 478 #endif 479 // Make a simple copy of the incoming state. 480 for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 481 set_type_at(c, incoming->type_at(c)); 482 } 483 return true; // it is always different the first time 484 } 485 #ifdef ASSERT 486 if (stack_size() != incoming->stack_size()) { 487 _outer->method()->print_codes(); 488 tty->print_cr("!!!! Stack size conflict"); 489 tty->print_cr("Current state:"); 490 print_on(tty); 491 tty->print_cr("Incoming state:"); 492 ((StateVector*)incoming)->print_on(tty); 493 } 494 #endif 495 assert(stack_size() == incoming->stack_size(), "sanity"); 496 497 bool different = false; 498 Cell limit = limit_cell(); 499 for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 500 ciType* t1 = type_at(c); 501 ciType* t2 = incoming->type_at(c); 502 if (!t1->equals(t2)) { 503 ciType* new_type = type_meet(t1, t2); 504 if (!t1->equals(new_type)) { 505 set_type_at(c, new_type); 506 different = true; 507 } 508 } 509 } 510 return different; 511 } 512 513 // ------------------------------------------------------------------ 514 // ciTypeFlow::StateVector::meet_exception 515 // 516 // Meets this StateVector with another, destructively modifying this 517 // one. The incoming state is coming via an exception. Returns true 518 // if any modification takes place. 519 bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc, 520 const ciTypeFlow::StateVector* incoming) { 521 if (monitor_count() == -1) { 522 set_monitor_count(incoming->monitor_count()); 523 } 524 assert(monitor_count() == incoming->monitor_count(), "monitors must match"); 525 526 if (stack_size() == -1) { 527 set_stack_size(1); 528 } 529 530 assert(stack_size() == 1, "must have one-element stack"); 531 532 bool different = false; 533 534 // Meet locals from incoming array. 535 Cell limit = local(_outer->max_locals()-1); 536 for (Cell c = start_cell(); c <= limit; c = next_cell(c)) { 537 ciType* t1 = type_at(c); 538 ciType* t2 = incoming->type_at(c); 539 if (!t1->equals(t2)) { 540 ciType* new_type = type_meet(t1, t2); 541 if (!t1->equals(new_type)) { 542 set_type_at(c, new_type); 543 different = true; 544 } 545 } 546 } 547 548 // Handle stack separately. When an exception occurs, the 549 // only stack entry is the exception instance. 550 ciType* tos_type = type_at_tos(); 551 if (!tos_type->equals(exc)) { 552 ciType* new_type = type_meet(tos_type, exc); 553 if (!tos_type->equals(new_type)) { 554 set_type_at_tos(new_type); 555 different = true; 556 } 557 } 558 559 return different; 560 } 561 562 // ------------------------------------------------------------------ 563 // ciTypeFlow::StateVector::push_translate 564 void ciTypeFlow::StateVector::push_translate(ciType* type) { 565 BasicType basic_type = type->basic_type(); 566 if (basic_type == T_BOOLEAN || basic_type == T_CHAR || 567 basic_type == T_BYTE || basic_type == T_SHORT) { 568 push_int(); 569 } else { 570 push(type); 571 if (type->is_two_word()) { 572 push(half_type(type)); 573 } 574 } 575 } 576 577 // ------------------------------------------------------------------ 578 // ciTypeFlow::StateVector::do_aload 579 void ciTypeFlow::StateVector::do_aload(ciBytecodeStream* str) { 580 pop_int(); 581 ciArrayKlass* array_klass = pop_objOrValueArray(); 582 if (array_klass == NULL) { 583 // Did aload on a null reference; push a null and ignore the exception. 584 // This instruction will never continue normally. All we have to do 585 // is report a value that will meet correctly with any downstream 586 // reference types on paths that will truly be executed. This null type 587 // meets with any reference type to yield that same reference type. 588 // (The compiler will generate an unconditional exception here.) 589 push(null_type()); 590 return; 591 } 592 if (!array_klass->is_loaded()) { 593 // Only fails for some -Xcomp runs 594 trap(str, array_klass, 595 Deoptimization::make_trap_request 596 (Deoptimization::Reason_unloaded, 597 Deoptimization::Action_reinterpret)); 598 return; 599 } 600 ciKlass* element_klass = array_klass->element_klass(); 601 if (!element_klass->is_loaded() && element_klass->is_instance_klass()) { 602 Untested("unloaded array element class in ciTypeFlow"); 603 trap(str, element_klass, 604 Deoptimization::make_trap_request 605 (Deoptimization::Reason_unloaded, 606 Deoptimization::Action_reinterpret)); 607 } else { 608 if (element_klass->is_valuetype()) { 609 // Value type array elements are never null 610 push(outer()->mark_as_never_null(element_klass)); 611 } else { 612 push_object(element_klass); 613 } 614 } 615 } 616 617 618 // ------------------------------------------------------------------ 619 // ciTypeFlow::StateVector::do_checkcast 620 void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) { 621 bool will_link; 622 ciKlass* klass = str->get_klass(will_link); 623 if (!will_link) { 624 // VM's interpreter will not load 'klass' if object is NULL. 625 // Type flow after this block may still be needed in two situations: 626 // 1) C2 uses do_null_assert() and continues compilation for later blocks 627 // 2) C2 does an OSR compile in a later block (see bug 4778368). 628 pop_object(); 629 do_null_assert(klass); 630 } else { 631 pop_object(); 632 if (str->get_never_null()) { 633 // Casting to a Q-Type contains a NULL check 634 assert(klass->is_valuetype(), "must be a value type"); 635 push(outer()->mark_as_never_null(klass)); 636 } else { 637 push_object(klass); 638 } 639 } 640 } 641 642 // ------------------------------------------------------------------ 643 // ciTypeFlow::StateVector::do_getfield 644 void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) { 645 // could add assert here for type of object. 646 pop_object(); 647 do_getstatic(str); 648 } 649 650 // ------------------------------------------------------------------ 651 // ciTypeFlow::StateVector::do_getstatic 652 void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) { 653 bool will_link; 654 ciField* field = str->get_field(will_link); 655 if (!will_link) { 656 trap(str, field->holder(), str->get_field_holder_index()); 657 } else { 658 ciType* field_type = field->type(); 659 if (!field_type->is_loaded()) { 660 // Normally, we need the field's type to be loaded if we are to 661 // do anything interesting with its value. 662 // We used to do this: trap(str, str->get_field_signature_index()); 663 // 664 // There is one good reason not to trap here. Execution can 665 // get past this "getfield" or "getstatic" if the value of 666 // the field is null. As long as the value is null, the class 667 // does not need to be loaded! The compiler must assume that 668 // the value of the unloaded class reference is null; if the code 669 // ever sees a non-null value, loading has occurred. 670 // 671 // This actually happens often enough to be annoying. If the 672 // compiler throws an uncommon trap at this bytecode, you can 673 // get an endless loop of recompilations, when all the code 674 // needs to do is load a series of null values. Also, a trap 675 // here can make an OSR entry point unreachable, triggering the 676 // assert on non_osr_block in ciTypeFlow::get_start_state. 677 // (See bug 4379915.) 678 do_null_assert(field_type->as_klass()); 679 } else { 680 if (field->is_flattenable()) { 681 // A flattenable field is never null 682 field_type = outer()->mark_as_never_null(field_type); 683 } 684 push_translate(field_type); 685 } 686 } 687 } 688 689 // ------------------------------------------------------------------ 690 // ciTypeFlow::StateVector::do_invoke 691 void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str, 692 bool has_receiver) { 693 bool will_link; 694 ciSignature* declared_signature = NULL; 695 ciMethod* callee = str->get_method(will_link, &declared_signature); 696 assert(declared_signature != NULL, "cannot be null"); 697 if (!will_link) { 698 // We weren't able to find the method. 699 if (str->cur_bc() == Bytecodes::_invokedynamic) { 700 trap(str, NULL, 701 Deoptimization::make_trap_request 702 (Deoptimization::Reason_uninitialized, 703 Deoptimization::Action_reinterpret)); 704 } else { 705 ciKlass* unloaded_holder = callee->holder(); 706 trap(str, unloaded_holder, str->get_method_holder_index()); 707 } 708 } else { 709 // We are using the declared signature here because it might be 710 // different from the callee signature (Cf. invokedynamic and 711 // invokehandle). 712 ciSignatureStream sigstr(declared_signature); 713 const int arg_size = declared_signature->size(); 714 const int stack_base = stack_size() - arg_size; 715 int i = 0; 716 for( ; !sigstr.at_return_type(); sigstr.next()) { 717 ciType* type = sigstr.type(); 718 ciType* stack_type = type_at(stack(stack_base + i++)); 719 // Do I want to check this type? 720 // assert(stack_type->is_subtype_of(type), "bad type for field value"); 721 if (type->is_two_word()) { 722 ciType* stack_type2 = type_at(stack(stack_base + i++)); 723 assert(stack_type2->equals(half_type(type)), "must be 2nd half"); 724 } 725 } 726 assert(arg_size == i, "must match"); 727 for (int j = 0; j < arg_size; j++) { 728 pop(); 729 } 730 if (has_receiver) { 731 // Check this? 732 pop_object(); 733 } 734 assert(!sigstr.is_done(), "must have return type"); 735 ciType* return_type = sigstr.type(); 736 if (!return_type->is_void()) { 737 if (!return_type->is_loaded()) { 738 // As in do_getstatic(), generally speaking, we need the return type to 739 // be loaded if we are to do anything interesting with its value. 740 // We used to do this: trap(str, str->get_method_signature_index()); 741 // 742 // We do not trap here since execution can get past this invoke if 743 // the return value is null. As long as the value is null, the class 744 // does not need to be loaded! The compiler must assume that 745 // the value of the unloaded class reference is null; if the code 746 // ever sees a non-null value, loading has occurred. 747 // 748 // See do_getstatic() for similar explanation, as well as bug 4684993. 749 do_null_assert(return_type->as_klass()); 750 } else { 751 if (sigstr.is_never_null()) { 752 return_type = outer()->mark_as_never_null(return_type); 753 } 754 push_translate(return_type); 755 } 756 } 757 } 758 } 759 760 // ------------------------------------------------------------------ 761 // ciTypeFlow::StateVector::do_jsr 762 void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) { 763 push(ciReturnAddress::make(str->next_bci())); 764 } 765 766 // ------------------------------------------------------------------ 767 // ciTypeFlow::StateVector::do_ldc 768 void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) { 769 ciConstant con = str->get_constant(); 770 BasicType basic_type = con.basic_type(); 771 if (basic_type == T_ILLEGAL) { 772 // OutOfMemoryError in the CI while loading constant 773 push_null(); 774 outer()->record_failure("ldc did not link"); 775 return; 776 } 777 if (basic_type == T_OBJECT || basic_type == T_VALUETYPE || basic_type == T_ARRAY) { 778 ciObject* obj = con.as_object(); 779 if (obj->is_null_object()) { 780 push_null(); 781 } else { 782 assert(obj->is_instance() || obj->is_array(), "must be java_mirror of klass"); 783 ciType* type = obj->klass(); 784 if (type->is_valuetype()) { 785 type = outer()->mark_as_never_null(type); 786 } 787 push(type); 788 } 789 } else { 790 push_translate(ciType::make(basic_type)); 791 } 792 } 793 794 // ------------------------------------------------------------------ 795 // ciTypeFlow::StateVector::do_multianewarray 796 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) { 797 int dimensions = str->get_dimensions(); 798 bool will_link; 799 ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass(); 800 if (!will_link) { 801 trap(str, array_klass, str->get_klass_index()); 802 } else { 803 for (int i = 0; i < dimensions; i++) { 804 pop_int(); 805 } 806 push_object(array_klass); 807 } 808 } 809 810 // ------------------------------------------------------------------ 811 // ciTypeFlow::StateVector::do_new 812 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) { 813 bool will_link; 814 ciKlass* klass = str->get_klass(will_link); 815 if (!will_link || str->is_unresolved_klass()) { 816 trap(str, klass, str->get_klass_index()); 817 } else { 818 push_object(klass); 819 } 820 } 821 822 // ------------------------------------------------------------------ 823 // ciTypeFlow::StateVector::do_defaultvalue 824 void ciTypeFlow::StateVector::do_defaultvalue(ciBytecodeStream* str) { 825 bool will_link; 826 ciKlass* klass = str->get_klass(will_link); 827 if (!will_link) { 828 trap(str, klass, str->get_klass_index()); 829 } else { 830 // The default value type is never null 831 push(outer()->mark_as_never_null(klass)); 832 } 833 } 834 835 // ------------------------------------------------------------------ 836 // ciTypeFlow::StateVector::do_withfield 837 void ciTypeFlow::StateVector::do_withfield(ciBytecodeStream* str) { 838 bool will_link; 839 ciField* field = str->get_field(will_link); 840 ciKlass* klass = field->holder(); 841 if (!will_link) { 842 trap(str, klass, str->get_field_holder_index()); 843 } else { 844 ciType* type = pop_value(); 845 ciType* field_type = field->type(); 846 assert(field_type->is_loaded(), "field type must be loaded"); 847 if (field_type->is_two_word()) { 848 ciType* type2 = pop_value(); 849 assert(type2->is_two_word(), "must be 2nd half"); 850 assert(type == half_type(type2), "must be 2nd half"); 851 } 852 pop_object(); 853 // The newly created value type can never be null 854 push(outer()->mark_as_never_null(klass)); 855 } 856 } 857 858 // ------------------------------------------------------------------ 859 // ciTypeFlow::StateVector::do_newarray 860 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) { 861 pop_int(); 862 ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index()); 863 push_object(klass); 864 } 865 866 // ------------------------------------------------------------------ 867 // ciTypeFlow::StateVector::do_putfield 868 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) { 869 do_putstatic(str); 870 if (_trap_bci != -1) return; // unloaded field holder, etc. 871 // could add assert here for type of object. 872 pop_object(); 873 } 874 875 // ------------------------------------------------------------------ 876 // ciTypeFlow::StateVector::do_putstatic 877 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) { 878 bool will_link; 879 ciField* field = str->get_field(will_link); 880 if (!will_link) { 881 trap(str, field->holder(), str->get_field_holder_index()); 882 } else { 883 ciType* field_type = field->type(); 884 ciType* type = pop_value(); 885 // Do I want to check this type? 886 // assert(type->is_subtype_of(field_type), "bad type for field value"); 887 if (field_type->is_two_word()) { 888 ciType* type2 = pop_value(); 889 assert(type2->is_two_word(), "must be 2nd half"); 890 assert(type == half_type(type2), "must be 2nd half"); 891 } 892 } 893 } 894 895 // ------------------------------------------------------------------ 896 // ciTypeFlow::StateVector::do_ret 897 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) { 898 Cell index = local(str->get_index()); 899 900 ciType* address = type_at(index); 901 assert(address->is_return_address(), "bad return address"); 902 set_type_at(index, bottom_type()); 903 } 904 905 // ------------------------------------------------------------------ 906 // ciTypeFlow::StateVector::trap 907 // 908 // Stop interpretation of this path with a trap. 909 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) { 910 _trap_bci = str->cur_bci(); 911 _trap_index = index; 912 913 // Log information about this trap: 914 CompileLog* log = outer()->env()->log(); 915 if (log != NULL) { 916 int mid = log->identify(outer()->method()); 917 int kid = (klass == NULL)? -1: log->identify(klass); 918 log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci()); 919 char buf[100]; 920 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf), 921 index)); 922 if (kid >= 0) 923 log->print(" klass='%d'", kid); 924 log->end_elem(); 925 } 926 } 927 928 // ------------------------------------------------------------------ 929 // ciTypeFlow::StateVector::do_null_assert 930 // Corresponds to graphKit::do_null_assert. 931 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) { 932 if (unloaded_klass->is_loaded()) { 933 // We failed to link, but we can still compute with this class, 934 // since it is loaded somewhere. The compiler will uncommon_trap 935 // if the object is not null, but the typeflow pass can not assume 936 // that the object will be null, otherwise it may incorrectly tell 937 // the parser that an object is known to be null. 4761344, 4807707 938 push_object(unloaded_klass); 939 } else { 940 // The class is not loaded anywhere. It is safe to model the 941 // null in the typestates, because we can compile in a null check 942 // which will deoptimize us if someone manages to load the 943 // class later. 944 push_null(); 945 } 946 } 947 948 949 // ------------------------------------------------------------------ 950 // ciTypeFlow::StateVector::apply_one_bytecode 951 // 952 // Apply the effect of one bytecode to this StateVector 953 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) { 954 _trap_bci = -1; 955 _trap_index = 0; 956 957 if (CITraceTypeFlow) { 958 tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(), 959 Bytecodes::name(str->cur_bc())); 960 } 961 962 switch(str->cur_bc()) { 963 case Bytecodes::_aaload: do_aload(str); break; 964 965 case Bytecodes::_aastore: 966 { 967 pop_object(); 968 pop_int(); 969 pop_objOrValueArray(); 970 break; 971 } 972 case Bytecodes::_aconst_null: 973 { 974 push_null(); 975 break; 976 } 977 case Bytecodes::_aload: load_local_object(str->get_index()); break; 978 case Bytecodes::_aload_0: load_local_object(0); break; 979 case Bytecodes::_aload_1: load_local_object(1); break; 980 case Bytecodes::_aload_2: load_local_object(2); break; 981 case Bytecodes::_aload_3: load_local_object(3); break; 982 983 case Bytecodes::_anewarray: 984 { 985 pop_int(); 986 bool will_link; 987 ciKlass* element_klass = str->get_klass(will_link); 988 if (!will_link) { 989 trap(str, element_klass, str->get_klass_index()); 990 } else { 991 push_object(ciArrayKlass::make(element_klass)); 992 } 993 break; 994 } 995 case Bytecodes::_areturn: 996 case Bytecodes::_ifnonnull: 997 case Bytecodes::_ifnull: 998 { 999 pop_object(); 1000 break; 1001 } 1002 case Bytecodes::_monitorenter: 1003 { 1004 pop_object(); 1005 set_monitor_count(monitor_count() + 1); 1006 break; 1007 } 1008 case Bytecodes::_monitorexit: 1009 { 1010 pop_object(); 1011 assert(monitor_count() > 0, "must be a monitor to exit from"); 1012 set_monitor_count(monitor_count() - 1); 1013 break; 1014 } 1015 case Bytecodes::_arraylength: 1016 { 1017 pop_array(); 1018 push_int(); 1019 break; 1020 } 1021 case Bytecodes::_astore: store_local_object(str->get_index()); break; 1022 case Bytecodes::_astore_0: store_local_object(0); break; 1023 case Bytecodes::_astore_1: store_local_object(1); break; 1024 case Bytecodes::_astore_2: store_local_object(2); break; 1025 case Bytecodes::_astore_3: store_local_object(3); break; 1026 1027 case Bytecodes::_athrow: 1028 { 1029 NEEDS_CLEANUP; 1030 pop_object(); 1031 break; 1032 } 1033 case Bytecodes::_baload: 1034 case Bytecodes::_caload: 1035 case Bytecodes::_iaload: 1036 case Bytecodes::_saload: 1037 { 1038 pop_int(); 1039 ciTypeArrayKlass* array_klass = pop_typeArray(); 1040 // Put assert here for right type? 1041 push_int(); 1042 break; 1043 } 1044 case Bytecodes::_bastore: 1045 case Bytecodes::_castore: 1046 case Bytecodes::_iastore: 1047 case Bytecodes::_sastore: 1048 { 1049 pop_int(); 1050 pop_int(); 1051 pop_typeArray(); 1052 // assert here? 1053 break; 1054 } 1055 case Bytecodes::_bipush: 1056 case Bytecodes::_iconst_m1: 1057 case Bytecodes::_iconst_0: 1058 case Bytecodes::_iconst_1: 1059 case Bytecodes::_iconst_2: 1060 case Bytecodes::_iconst_3: 1061 case Bytecodes::_iconst_4: 1062 case Bytecodes::_iconst_5: 1063 case Bytecodes::_sipush: 1064 { 1065 push_int(); 1066 break; 1067 } 1068 case Bytecodes::_checkcast: do_checkcast(str); break; 1069 1070 case Bytecodes::_d2f: 1071 { 1072 pop_double(); 1073 push_float(); 1074 break; 1075 } 1076 case Bytecodes::_d2i: 1077 { 1078 pop_double(); 1079 push_int(); 1080 break; 1081 } 1082 case Bytecodes::_d2l: 1083 { 1084 pop_double(); 1085 push_long(); 1086 break; 1087 } 1088 case Bytecodes::_dadd: 1089 case Bytecodes::_ddiv: 1090 case Bytecodes::_dmul: 1091 case Bytecodes::_drem: 1092 case Bytecodes::_dsub: 1093 { 1094 pop_double(); 1095 pop_double(); 1096 push_double(); 1097 break; 1098 } 1099 case Bytecodes::_daload: 1100 { 1101 pop_int(); 1102 ciTypeArrayKlass* array_klass = pop_typeArray(); 1103 // Put assert here for right type? 1104 push_double(); 1105 break; 1106 } 1107 case Bytecodes::_dastore: 1108 { 1109 pop_double(); 1110 pop_int(); 1111 pop_typeArray(); 1112 // assert here? 1113 break; 1114 } 1115 case Bytecodes::_dcmpg: 1116 case Bytecodes::_dcmpl: 1117 { 1118 pop_double(); 1119 pop_double(); 1120 push_int(); 1121 break; 1122 } 1123 case Bytecodes::_dconst_0: 1124 case Bytecodes::_dconst_1: 1125 { 1126 push_double(); 1127 break; 1128 } 1129 case Bytecodes::_dload: load_local_double(str->get_index()); break; 1130 case Bytecodes::_dload_0: load_local_double(0); break; 1131 case Bytecodes::_dload_1: load_local_double(1); break; 1132 case Bytecodes::_dload_2: load_local_double(2); break; 1133 case Bytecodes::_dload_3: load_local_double(3); break; 1134 1135 case Bytecodes::_dneg: 1136 { 1137 pop_double(); 1138 push_double(); 1139 break; 1140 } 1141 case Bytecodes::_dreturn: 1142 { 1143 pop_double(); 1144 break; 1145 } 1146 case Bytecodes::_dstore: store_local_double(str->get_index()); break; 1147 case Bytecodes::_dstore_0: store_local_double(0); break; 1148 case Bytecodes::_dstore_1: store_local_double(1); break; 1149 case Bytecodes::_dstore_2: store_local_double(2); break; 1150 case Bytecodes::_dstore_3: store_local_double(3); break; 1151 1152 case Bytecodes::_dup: 1153 { 1154 push(type_at_tos()); 1155 break; 1156 } 1157 case Bytecodes::_dup_x1: 1158 { 1159 ciType* value1 = pop_value(); 1160 ciType* value2 = pop_value(); 1161 push(value1); 1162 push(value2); 1163 push(value1); 1164 break; 1165 } 1166 case Bytecodes::_dup_x2: 1167 { 1168 ciType* value1 = pop_value(); 1169 ciType* value2 = pop_value(); 1170 ciType* value3 = pop_value(); 1171 push(value1); 1172 push(value3); 1173 push(value2); 1174 push(value1); 1175 break; 1176 } 1177 case Bytecodes::_dup2: 1178 { 1179 ciType* value1 = pop_value(); 1180 ciType* value2 = pop_value(); 1181 push(value2); 1182 push(value1); 1183 push(value2); 1184 push(value1); 1185 break; 1186 } 1187 case Bytecodes::_dup2_x1: 1188 { 1189 ciType* value1 = pop_value(); 1190 ciType* value2 = pop_value(); 1191 ciType* value3 = pop_value(); 1192 push(value2); 1193 push(value1); 1194 push(value3); 1195 push(value2); 1196 push(value1); 1197 break; 1198 } 1199 case Bytecodes::_dup2_x2: 1200 { 1201 ciType* value1 = pop_value(); 1202 ciType* value2 = pop_value(); 1203 ciType* value3 = pop_value(); 1204 ciType* value4 = pop_value(); 1205 push(value2); 1206 push(value1); 1207 push(value4); 1208 push(value3); 1209 push(value2); 1210 push(value1); 1211 break; 1212 } 1213 case Bytecodes::_f2d: 1214 { 1215 pop_float(); 1216 push_double(); 1217 break; 1218 } 1219 case Bytecodes::_f2i: 1220 { 1221 pop_float(); 1222 push_int(); 1223 break; 1224 } 1225 case Bytecodes::_f2l: 1226 { 1227 pop_float(); 1228 push_long(); 1229 break; 1230 } 1231 case Bytecodes::_fadd: 1232 case Bytecodes::_fdiv: 1233 case Bytecodes::_fmul: 1234 case Bytecodes::_frem: 1235 case Bytecodes::_fsub: 1236 { 1237 pop_float(); 1238 pop_float(); 1239 push_float(); 1240 break; 1241 } 1242 case Bytecodes::_faload: 1243 { 1244 pop_int(); 1245 ciTypeArrayKlass* array_klass = pop_typeArray(); 1246 // Put assert here. 1247 push_float(); 1248 break; 1249 } 1250 case Bytecodes::_fastore: 1251 { 1252 pop_float(); 1253 pop_int(); 1254 ciTypeArrayKlass* array_klass = pop_typeArray(); 1255 // Put assert here. 1256 break; 1257 } 1258 case Bytecodes::_fcmpg: 1259 case Bytecodes::_fcmpl: 1260 { 1261 pop_float(); 1262 pop_float(); 1263 push_int(); 1264 break; 1265 } 1266 case Bytecodes::_fconst_0: 1267 case Bytecodes::_fconst_1: 1268 case Bytecodes::_fconst_2: 1269 { 1270 push_float(); 1271 break; 1272 } 1273 case Bytecodes::_fload: load_local_float(str->get_index()); break; 1274 case Bytecodes::_fload_0: load_local_float(0); break; 1275 case Bytecodes::_fload_1: load_local_float(1); break; 1276 case Bytecodes::_fload_2: load_local_float(2); break; 1277 case Bytecodes::_fload_3: load_local_float(3); break; 1278 1279 case Bytecodes::_fneg: 1280 { 1281 pop_float(); 1282 push_float(); 1283 break; 1284 } 1285 case Bytecodes::_freturn: 1286 { 1287 pop_float(); 1288 break; 1289 } 1290 case Bytecodes::_fstore: store_local_float(str->get_index()); break; 1291 case Bytecodes::_fstore_0: store_local_float(0); break; 1292 case Bytecodes::_fstore_1: store_local_float(1); break; 1293 case Bytecodes::_fstore_2: store_local_float(2); break; 1294 case Bytecodes::_fstore_3: store_local_float(3); break; 1295 1296 case Bytecodes::_getfield: do_getfield(str); break; 1297 case Bytecodes::_getstatic: do_getstatic(str); break; 1298 1299 case Bytecodes::_goto: 1300 case Bytecodes::_goto_w: 1301 case Bytecodes::_nop: 1302 case Bytecodes::_return: 1303 { 1304 // do nothing. 1305 break; 1306 } 1307 case Bytecodes::_i2b: 1308 case Bytecodes::_i2c: 1309 case Bytecodes::_i2s: 1310 case Bytecodes::_ineg: 1311 { 1312 pop_int(); 1313 push_int(); 1314 break; 1315 } 1316 case Bytecodes::_i2d: 1317 { 1318 pop_int(); 1319 push_double(); 1320 break; 1321 } 1322 case Bytecodes::_i2f: 1323 { 1324 pop_int(); 1325 push_float(); 1326 break; 1327 } 1328 case Bytecodes::_i2l: 1329 { 1330 pop_int(); 1331 push_long(); 1332 break; 1333 } 1334 case Bytecodes::_iadd: 1335 case Bytecodes::_iand: 1336 case Bytecodes::_idiv: 1337 case Bytecodes::_imul: 1338 case Bytecodes::_ior: 1339 case Bytecodes::_irem: 1340 case Bytecodes::_ishl: 1341 case Bytecodes::_ishr: 1342 case Bytecodes::_isub: 1343 case Bytecodes::_iushr: 1344 case Bytecodes::_ixor: 1345 { 1346 pop_int(); 1347 pop_int(); 1348 push_int(); 1349 break; 1350 } 1351 case Bytecodes::_if_acmpeq: 1352 case Bytecodes::_if_acmpne: 1353 { 1354 pop_object(); 1355 pop_object(); 1356 break; 1357 } 1358 case Bytecodes::_if_icmpeq: 1359 case Bytecodes::_if_icmpge: 1360 case Bytecodes::_if_icmpgt: 1361 case Bytecodes::_if_icmple: 1362 case Bytecodes::_if_icmplt: 1363 case Bytecodes::_if_icmpne: 1364 { 1365 pop_int(); 1366 pop_int(); 1367 break; 1368 } 1369 case Bytecodes::_ifeq: 1370 case Bytecodes::_ifle: 1371 case Bytecodes::_iflt: 1372 case Bytecodes::_ifge: 1373 case Bytecodes::_ifgt: 1374 case Bytecodes::_ifne: 1375 case Bytecodes::_ireturn: 1376 case Bytecodes::_lookupswitch: 1377 case Bytecodes::_tableswitch: 1378 { 1379 pop_int(); 1380 break; 1381 } 1382 case Bytecodes::_iinc: 1383 { 1384 int lnum = str->get_index(); 1385 check_int(local(lnum)); 1386 store_to_local(lnum); 1387 break; 1388 } 1389 case Bytecodes::_iload: load_local_int(str->get_index()); break; 1390 case Bytecodes::_iload_0: load_local_int(0); break; 1391 case Bytecodes::_iload_1: load_local_int(1); break; 1392 case Bytecodes::_iload_2: load_local_int(2); break; 1393 case Bytecodes::_iload_3: load_local_int(3); break; 1394 1395 case Bytecodes::_instanceof: 1396 { 1397 // Check for uncommon trap: 1398 do_checkcast(str); 1399 pop_object(); 1400 push_int(); 1401 break; 1402 } 1403 case Bytecodes::_invokeinterface: do_invoke(str, true); break; 1404 case Bytecodes::_invokespecial: do_invoke(str, true); break; 1405 case Bytecodes::_invokestatic: do_invoke(str, false); break; 1406 case Bytecodes::_invokevirtual: do_invoke(str, true); break; 1407 case Bytecodes::_invokedynamic: do_invoke(str, false); break; 1408 1409 case Bytecodes::_istore: store_local_int(str->get_index()); break; 1410 case Bytecodes::_istore_0: store_local_int(0); break; 1411 case Bytecodes::_istore_1: store_local_int(1); break; 1412 case Bytecodes::_istore_2: store_local_int(2); break; 1413 case Bytecodes::_istore_3: store_local_int(3); break; 1414 1415 case Bytecodes::_jsr: 1416 case Bytecodes::_jsr_w: do_jsr(str); break; 1417 1418 case Bytecodes::_l2d: 1419 { 1420 pop_long(); 1421 push_double(); 1422 break; 1423 } 1424 case Bytecodes::_l2f: 1425 { 1426 pop_long(); 1427 push_float(); 1428 break; 1429 } 1430 case Bytecodes::_l2i: 1431 { 1432 pop_long(); 1433 push_int(); 1434 break; 1435 } 1436 case Bytecodes::_ladd: 1437 case Bytecodes::_land: 1438 case Bytecodes::_ldiv: 1439 case Bytecodes::_lmul: 1440 case Bytecodes::_lor: 1441 case Bytecodes::_lrem: 1442 case Bytecodes::_lsub: 1443 case Bytecodes::_lxor: 1444 { 1445 pop_long(); 1446 pop_long(); 1447 push_long(); 1448 break; 1449 } 1450 case Bytecodes::_laload: 1451 { 1452 pop_int(); 1453 ciTypeArrayKlass* array_klass = pop_typeArray(); 1454 // Put assert here for right type? 1455 push_long(); 1456 break; 1457 } 1458 case Bytecodes::_lastore: 1459 { 1460 pop_long(); 1461 pop_int(); 1462 pop_typeArray(); 1463 // assert here? 1464 break; 1465 } 1466 case Bytecodes::_lcmp: 1467 { 1468 pop_long(); 1469 pop_long(); 1470 push_int(); 1471 break; 1472 } 1473 case Bytecodes::_lconst_0: 1474 case Bytecodes::_lconst_1: 1475 { 1476 push_long(); 1477 break; 1478 } 1479 case Bytecodes::_ldc: 1480 case Bytecodes::_ldc_w: 1481 case Bytecodes::_ldc2_w: 1482 { 1483 do_ldc(str); 1484 break; 1485 } 1486 1487 case Bytecodes::_lload: load_local_long(str->get_index()); break; 1488 case Bytecodes::_lload_0: load_local_long(0); break; 1489 case Bytecodes::_lload_1: load_local_long(1); break; 1490 case Bytecodes::_lload_2: load_local_long(2); break; 1491 case Bytecodes::_lload_3: load_local_long(3); break; 1492 1493 case Bytecodes::_lneg: 1494 { 1495 pop_long(); 1496 push_long(); 1497 break; 1498 } 1499 case Bytecodes::_lreturn: 1500 { 1501 pop_long(); 1502 break; 1503 } 1504 case Bytecodes::_lshl: 1505 case Bytecodes::_lshr: 1506 case Bytecodes::_lushr: 1507 { 1508 pop_int(); 1509 pop_long(); 1510 push_long(); 1511 break; 1512 } 1513 case Bytecodes::_lstore: store_local_long(str->get_index()); break; 1514 case Bytecodes::_lstore_0: store_local_long(0); break; 1515 case Bytecodes::_lstore_1: store_local_long(1); break; 1516 case Bytecodes::_lstore_2: store_local_long(2); break; 1517 case Bytecodes::_lstore_3: store_local_long(3); break; 1518 1519 case Bytecodes::_multianewarray: do_multianewarray(str); break; 1520 1521 case Bytecodes::_new: do_new(str); break; 1522 1523 case Bytecodes::_defaultvalue: do_defaultvalue(str); break; 1524 case Bytecodes::_withfield: do_withfield(str); break; 1525 1526 case Bytecodes::_newarray: do_newarray(str); break; 1527 1528 case Bytecodes::_pop: 1529 { 1530 pop(); 1531 break; 1532 } 1533 case Bytecodes::_pop2: 1534 { 1535 pop(); 1536 pop(); 1537 break; 1538 } 1539 1540 case Bytecodes::_putfield: do_putfield(str); break; 1541 case Bytecodes::_putstatic: do_putstatic(str); break; 1542 1543 case Bytecodes::_ret: do_ret(str); break; 1544 1545 case Bytecodes::_swap: 1546 { 1547 ciType* value1 = pop_value(); 1548 ciType* value2 = pop_value(); 1549 push(value1); 1550 push(value2); 1551 break; 1552 } 1553 1554 case Bytecodes::_wide: 1555 default: 1556 { 1557 // The iterator should skip this. 1558 ShouldNotReachHere(); 1559 break; 1560 } 1561 } 1562 1563 if (CITraceTypeFlow) { 1564 print_on(tty); 1565 } 1566 1567 return (_trap_bci != -1); 1568 } 1569 1570 #ifndef PRODUCT 1571 // ------------------------------------------------------------------ 1572 // ciTypeFlow::StateVector::print_cell_on 1573 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const { 1574 ciType* type = type_at(c); 1575 if (type == top_type()) { 1576 st->print("top"); 1577 } else if (type == bottom_type()) { 1578 st->print("bottom"); 1579 } else if (type == null_type()) { 1580 st->print("null"); 1581 } else if (type == long2_type()) { 1582 st->print("long2"); 1583 } else if (type == double2_type()) { 1584 st->print("double2"); 1585 } else if (is_int(type)) { 1586 st->print("int"); 1587 } else if (is_long(type)) { 1588 st->print("long"); 1589 } else if (is_float(type)) { 1590 st->print("float"); 1591 } else if (is_double(type)) { 1592 st->print("double"); 1593 } else if (type->is_return_address()) { 1594 st->print("address(%d)", type->as_return_address()->bci()); 1595 } else { 1596 if (type->is_klass()) { 1597 type->as_klass()->name()->print_symbol_on(st); 1598 } else { 1599 st->print("UNEXPECTED TYPE"); 1600 type->print(); 1601 } 1602 } 1603 } 1604 1605 // ------------------------------------------------------------------ 1606 // ciTypeFlow::StateVector::print_on 1607 void ciTypeFlow::StateVector::print_on(outputStream* st) const { 1608 int num_locals = _outer->max_locals(); 1609 int num_stack = stack_size(); 1610 int num_monitors = monitor_count(); 1611 st->print_cr(" State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors); 1612 if (num_stack >= 0) { 1613 int i; 1614 for (i = 0; i < num_locals; i++) { 1615 st->print(" local %2d : ", i); 1616 print_cell_on(st, local(i)); 1617 st->cr(); 1618 } 1619 for (i = 0; i < num_stack; i++) { 1620 st->print(" stack %2d : ", i); 1621 print_cell_on(st, stack(i)); 1622 st->cr(); 1623 } 1624 } 1625 } 1626 #endif 1627 1628 1629 // ------------------------------------------------------------------ 1630 // ciTypeFlow::SuccIter::next 1631 // 1632 void ciTypeFlow::SuccIter::next() { 1633 int succ_ct = _pred->successors()->length(); 1634 int next = _index + 1; 1635 if (next < succ_ct) { 1636 _index = next; 1637 _succ = _pred->successors()->at(next); 1638 return; 1639 } 1640 for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) { 1641 // Do not compile any code for unloaded exception types. 1642 // Following compiler passes are responsible for doing this also. 1643 ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i); 1644 if (exception_klass->is_loaded()) { 1645 _index = next; 1646 _succ = _pred->exceptions()->at(i); 1647 return; 1648 } 1649 next++; 1650 } 1651 _index = -1; 1652 _succ = NULL; 1653 } 1654 1655 // ------------------------------------------------------------------ 1656 // ciTypeFlow::SuccIter::set_succ 1657 // 1658 void ciTypeFlow::SuccIter::set_succ(Block* succ) { 1659 int succ_ct = _pred->successors()->length(); 1660 if (_index < succ_ct) { 1661 _pred->successors()->at_put(_index, succ); 1662 } else { 1663 int idx = _index - succ_ct; 1664 _pred->exceptions()->at_put(idx, succ); 1665 } 1666 } 1667 1668 // ciTypeFlow::Block 1669 // 1670 // A basic block. 1671 1672 // ------------------------------------------------------------------ 1673 // ciTypeFlow::Block::Block 1674 ciTypeFlow::Block::Block(ciTypeFlow* outer, 1675 ciBlock *ciblk, 1676 ciTypeFlow::JsrSet* jsrs) { 1677 _ciblock = ciblk; 1678 _exceptions = NULL; 1679 _exc_klasses = NULL; 1680 _successors = NULL; 1681 _predecessors = new (outer->arena()) GrowableArray<Block*>(outer->arena(), 1, 0, NULL); 1682 _state = new (outer->arena()) StateVector(outer); 1683 JsrSet* new_jsrs = 1684 new (outer->arena()) JsrSet(outer->arena(), jsrs->size()); 1685 jsrs->copy_into(new_jsrs); 1686 _jsrs = new_jsrs; 1687 _next = NULL; 1688 _on_work_list = false; 1689 _backedge_copy = false; 1690 _has_monitorenter = false; 1691 _trap_bci = -1; 1692 _trap_index = 0; 1693 df_init(); 1694 1695 if (CITraceTypeFlow) { 1696 tty->print_cr(">> Created new block"); 1697 print_on(tty); 1698 } 1699 1700 assert(this->outer() == outer, "outer link set up"); 1701 assert(!outer->have_block_count(), "must not have mapped blocks yet"); 1702 } 1703 1704 // ------------------------------------------------------------------ 1705 // ciTypeFlow::Block::df_init 1706 void ciTypeFlow::Block::df_init() { 1707 _pre_order = -1; assert(!has_pre_order(), ""); 1708 _post_order = -1; assert(!has_post_order(), ""); 1709 _loop = NULL; 1710 _irreducible_entry = false; 1711 _rpo_next = NULL; 1712 } 1713 1714 // ------------------------------------------------------------------ 1715 // ciTypeFlow::Block::successors 1716 // 1717 // Get the successors for this Block. 1718 GrowableArray<ciTypeFlow::Block*>* 1719 ciTypeFlow::Block::successors(ciBytecodeStream* str, 1720 ciTypeFlow::StateVector* state, 1721 ciTypeFlow::JsrSet* jsrs) { 1722 if (_successors == NULL) { 1723 if (CITraceTypeFlow) { 1724 tty->print(">> Computing successors for block "); 1725 print_value_on(tty); 1726 tty->cr(); 1727 } 1728 1729 ciTypeFlow* analyzer = outer(); 1730 Arena* arena = analyzer->arena(); 1731 Block* block = NULL; 1732 bool has_successor = !has_trap() && 1733 (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size()); 1734 if (!has_successor) { 1735 _successors = 1736 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1737 // No successors 1738 } else if (control() == ciBlock::fall_through_bci) { 1739 assert(str->cur_bci() == limit(), "bad block end"); 1740 // This block simply falls through to the next. 1741 _successors = 1742 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1743 1744 Block* block = analyzer->block_at(limit(), _jsrs); 1745 assert(_successors->length() == FALL_THROUGH, ""); 1746 _successors->append(block); 1747 } else { 1748 int current_bci = str->cur_bci(); 1749 int next_bci = str->next_bci(); 1750 int branch_bci = -1; 1751 Block* target = NULL; 1752 assert(str->next_bci() == limit(), "bad block end"); 1753 // This block is not a simple fall-though. Interpret 1754 // the current bytecode to find our successors. 1755 switch (str->cur_bc()) { 1756 case Bytecodes::_ifeq: case Bytecodes::_ifne: 1757 case Bytecodes::_iflt: case Bytecodes::_ifge: 1758 case Bytecodes::_ifgt: case Bytecodes::_ifle: 1759 case Bytecodes::_if_icmpeq: case Bytecodes::_if_icmpne: 1760 case Bytecodes::_if_icmplt: case Bytecodes::_if_icmpge: 1761 case Bytecodes::_if_icmpgt: case Bytecodes::_if_icmple: 1762 case Bytecodes::_if_acmpeq: case Bytecodes::_if_acmpne: 1763 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: 1764 // Our successors are the branch target and the next bci. 1765 branch_bci = str->get_dest(); 1766 _successors = 1767 new (arena) GrowableArray<Block*>(arena, 2, 0, NULL); 1768 assert(_successors->length() == IF_NOT_TAKEN, ""); 1769 _successors->append(analyzer->block_at(next_bci, jsrs)); 1770 assert(_successors->length() == IF_TAKEN, ""); 1771 _successors->append(analyzer->block_at(branch_bci, jsrs)); 1772 break; 1773 1774 case Bytecodes::_goto: 1775 branch_bci = str->get_dest(); 1776 _successors = 1777 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1778 assert(_successors->length() == GOTO_TARGET, ""); 1779 _successors->append(analyzer->block_at(branch_bci, jsrs)); 1780 break; 1781 1782 case Bytecodes::_jsr: 1783 branch_bci = str->get_dest(); 1784 _successors = 1785 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1786 assert(_successors->length() == GOTO_TARGET, ""); 1787 _successors->append(analyzer->block_at(branch_bci, jsrs)); 1788 break; 1789 1790 case Bytecodes::_goto_w: 1791 case Bytecodes::_jsr_w: 1792 _successors = 1793 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1794 assert(_successors->length() == GOTO_TARGET, ""); 1795 _successors->append(analyzer->block_at(str->get_far_dest(), jsrs)); 1796 break; 1797 1798 case Bytecodes::_tableswitch: { 1799 Bytecode_tableswitch tableswitch(str); 1800 1801 int len = tableswitch.length(); 1802 _successors = 1803 new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL); 1804 int bci = current_bci + tableswitch.default_offset(); 1805 Block* block = analyzer->block_at(bci, jsrs); 1806 assert(_successors->length() == SWITCH_DEFAULT, ""); 1807 _successors->append(block); 1808 while (--len >= 0) { 1809 int bci = current_bci + tableswitch.dest_offset_at(len); 1810 block = analyzer->block_at(bci, jsrs); 1811 assert(_successors->length() >= SWITCH_CASES, ""); 1812 _successors->append_if_missing(block); 1813 } 1814 break; 1815 } 1816 1817 case Bytecodes::_lookupswitch: { 1818 Bytecode_lookupswitch lookupswitch(str); 1819 1820 int npairs = lookupswitch.number_of_pairs(); 1821 _successors = 1822 new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL); 1823 int bci = current_bci + lookupswitch.default_offset(); 1824 Block* block = analyzer->block_at(bci, jsrs); 1825 assert(_successors->length() == SWITCH_DEFAULT, ""); 1826 _successors->append(block); 1827 while(--npairs >= 0) { 1828 LookupswitchPair pair = lookupswitch.pair_at(npairs); 1829 int bci = current_bci + pair.offset(); 1830 Block* block = analyzer->block_at(bci, jsrs); 1831 assert(_successors->length() >= SWITCH_CASES, ""); 1832 _successors->append_if_missing(block); 1833 } 1834 break; 1835 } 1836 1837 case Bytecodes::_athrow: 1838 case Bytecodes::_ireturn: 1839 case Bytecodes::_lreturn: 1840 case Bytecodes::_freturn: 1841 case Bytecodes::_dreturn: 1842 case Bytecodes::_areturn: 1843 case Bytecodes::_return: 1844 _successors = 1845 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1846 // No successors 1847 break; 1848 1849 case Bytecodes::_ret: { 1850 _successors = 1851 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1852 1853 Cell local = state->local(str->get_index()); 1854 ciType* return_address = state->type_at(local); 1855 assert(return_address->is_return_address(), "verify: wrong type"); 1856 int bci = return_address->as_return_address()->bci(); 1857 assert(_successors->length() == GOTO_TARGET, ""); 1858 _successors->append(analyzer->block_at(bci, jsrs)); 1859 break; 1860 } 1861 1862 case Bytecodes::_wide: 1863 default: 1864 ShouldNotReachHere(); 1865 break; 1866 } 1867 } 1868 1869 // Set predecessor information 1870 for (int i = 0; i < _successors->length(); i++) { 1871 Block* block = _successors->at(i); 1872 block->predecessors()->append(this); 1873 } 1874 } 1875 return _successors; 1876 } 1877 1878 // ------------------------------------------------------------------ 1879 // ciTypeFlow::Block:compute_exceptions 1880 // 1881 // Compute the exceptional successors and types for this Block. 1882 void ciTypeFlow::Block::compute_exceptions() { 1883 assert(_exceptions == NULL && _exc_klasses == NULL, "repeat"); 1884 1885 if (CITraceTypeFlow) { 1886 tty->print(">> Computing exceptions for block "); 1887 print_value_on(tty); 1888 tty->cr(); 1889 } 1890 1891 ciTypeFlow* analyzer = outer(); 1892 Arena* arena = analyzer->arena(); 1893 1894 // Any bci in the block will do. 1895 ciExceptionHandlerStream str(analyzer->method(), start()); 1896 1897 // Allocate our growable arrays. 1898 int exc_count = str.count(); 1899 _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL); 1900 _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count, 1901 0, NULL); 1902 1903 for ( ; !str.is_done(); str.next()) { 1904 ciExceptionHandler* handler = str.handler(); 1905 int bci = handler->handler_bci(); 1906 ciInstanceKlass* klass = NULL; 1907 if (bci == -1) { 1908 // There is no catch all. It is possible to exit the method. 1909 break; 1910 } 1911 if (handler->is_catch_all()) { 1912 klass = analyzer->env()->Throwable_klass(); 1913 } else { 1914 klass = handler->catch_klass(); 1915 } 1916 Block* block = analyzer->block_at(bci, _jsrs); 1917 _exceptions->append(block); 1918 block->predecessors()->append(this); 1919 _exc_klasses->append(klass); 1920 } 1921 } 1922 1923 // ------------------------------------------------------------------ 1924 // ciTypeFlow::Block::set_backedge_copy 1925 // Use this only to make a pre-existing public block into a backedge copy. 1926 void ciTypeFlow::Block::set_backedge_copy(bool z) { 1927 assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public"); 1928 _backedge_copy = z; 1929 } 1930 1931 // ------------------------------------------------------------------ 1932 // ciTypeFlow::Block::is_clonable_exit 1933 // 1934 // At most 2 normal successors, one of which continues looping, 1935 // and all exceptional successors must exit. 1936 bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) { 1937 int normal_cnt = 0; 1938 int in_loop_cnt = 0; 1939 for (SuccIter iter(this); !iter.done(); iter.next()) { 1940 Block* succ = iter.succ(); 1941 if (iter.is_normal_ctrl()) { 1942 if (++normal_cnt > 2) return false; 1943 if (lp->contains(succ->loop())) { 1944 if (++in_loop_cnt > 1) return false; 1945 } 1946 } else { 1947 if (lp->contains(succ->loop())) return false; 1948 } 1949 } 1950 return in_loop_cnt == 1; 1951 } 1952 1953 // ------------------------------------------------------------------ 1954 // ciTypeFlow::Block::looping_succ 1955 // 1956 ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) { 1957 assert(successors()->length() <= 2, "at most 2 normal successors"); 1958 for (SuccIter iter(this); !iter.done(); iter.next()) { 1959 Block* succ = iter.succ(); 1960 if (lp->contains(succ->loop())) { 1961 return succ; 1962 } 1963 } 1964 return NULL; 1965 } 1966 1967 #ifndef PRODUCT 1968 // ------------------------------------------------------------------ 1969 // ciTypeFlow::Block::print_value_on 1970 void ciTypeFlow::Block::print_value_on(outputStream* st) const { 1971 if (has_pre_order()) st->print("#%-2d ", pre_order()); 1972 if (has_rpo()) st->print("rpo#%-2d ", rpo()); 1973 st->print("[%d - %d)", start(), limit()); 1974 if (is_loop_head()) st->print(" lphd"); 1975 if (is_irreducible_entry()) st->print(" irred"); 1976 if (_jsrs->size() > 0) { st->print("/"); _jsrs->print_on(st); } 1977 if (is_backedge_copy()) st->print("/backedge_copy"); 1978 } 1979 1980 // ------------------------------------------------------------------ 1981 // ciTypeFlow::Block::print_on 1982 void ciTypeFlow::Block::print_on(outputStream* st) const { 1983 if ((Verbose || WizardMode) && (limit() >= 0)) { 1984 // Don't print 'dummy' blocks (i.e. blocks with limit() '-1') 1985 outer()->method()->print_codes_on(start(), limit(), st); 1986 } 1987 st->print_cr(" ==================================================== "); 1988 st->print (" "); 1989 print_value_on(st); 1990 st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr(); 1991 if (loop() && loop()->parent() != NULL) { 1992 st->print(" loops:"); 1993 Loop* lp = loop(); 1994 do { 1995 st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order()); 1996 if (lp->is_irreducible()) st->print("(ir)"); 1997 lp = lp->parent(); 1998 } while (lp->parent() != NULL); 1999 } 2000 st->cr(); 2001 _state->print_on(st); 2002 if (_successors == NULL) { 2003 st->print_cr(" No successor information"); 2004 } else { 2005 int num_successors = _successors->length(); 2006 st->print_cr(" Successors : %d", num_successors); 2007 for (int i = 0; i < num_successors; i++) { 2008 Block* successor = _successors->at(i); 2009 st->print(" "); 2010 successor->print_value_on(st); 2011 st->cr(); 2012 } 2013 } 2014 if (_predecessors == NULL) { 2015 st->print_cr(" No predecessor information"); 2016 } else { 2017 int num_predecessors = _predecessors->length(); 2018 st->print_cr(" Predecessors : %d", num_predecessors); 2019 for (int i = 0; i < num_predecessors; i++) { 2020 Block* predecessor = _predecessors->at(i); 2021 st->print(" "); 2022 predecessor->print_value_on(st); 2023 st->cr(); 2024 } 2025 } 2026 if (_exceptions == NULL) { 2027 st->print_cr(" No exception information"); 2028 } else { 2029 int num_exceptions = _exceptions->length(); 2030 st->print_cr(" Exceptions : %d", num_exceptions); 2031 for (int i = 0; i < num_exceptions; i++) { 2032 Block* exc_succ = _exceptions->at(i); 2033 ciInstanceKlass* exc_klass = _exc_klasses->at(i); 2034 st->print(" "); 2035 exc_succ->print_value_on(st); 2036 st->print(" -- "); 2037 exc_klass->name()->print_symbol_on(st); 2038 st->cr(); 2039 } 2040 } 2041 if (has_trap()) { 2042 st->print_cr(" Traps on %d with trap index %d", trap_bci(), trap_index()); 2043 } 2044 st->print_cr(" ==================================================== "); 2045 } 2046 #endif 2047 2048 #ifndef PRODUCT 2049 // ------------------------------------------------------------------ 2050 // ciTypeFlow::LocalSet::print_on 2051 void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const { 2052 st->print("{"); 2053 for (int i = 0; i < max; i++) { 2054 if (test(i)) st->print(" %d", i); 2055 } 2056 if (limit > max) { 2057 st->print(" %d..%d ", max, limit); 2058 } 2059 st->print(" }"); 2060 } 2061 #endif 2062 2063 // ciTypeFlow 2064 // 2065 // This is a pass over the bytecodes which computes the following: 2066 // basic block structure 2067 // interpreter type-states (a la the verifier) 2068 2069 // ------------------------------------------------------------------ 2070 // ciTypeFlow::ciTypeFlow 2071 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) { 2072 _env = env; 2073 _method = method; 2074 _methodBlocks = method->get_method_blocks(); 2075 _max_locals = method->max_locals(); 2076 _max_stack = method->max_stack(); 2077 _code_size = method->code_size(); 2078 _has_irreducible_entry = false; 2079 _osr_bci = osr_bci; 2080 _failure_reason = NULL; 2081 assert(0 <= start_bci() && start_bci() < code_size() , "correct osr_bci argument: 0 <= %d < %d", start_bci(), code_size()); 2082 _work_list = NULL; 2083 2084 _ciblock_count = _methodBlocks->num_blocks(); 2085 _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count); 2086 for (int i = 0; i < _ciblock_count; i++) { 2087 _idx_to_blocklist[i] = NULL; 2088 } 2089 _block_map = NULL; // until all blocks are seen 2090 _jsr_count = 0; 2091 _jsr_records = NULL; 2092 } 2093 2094 // ------------------------------------------------------------------ 2095 // ciTypeFlow::work_list_next 2096 // 2097 // Get the next basic block from our work list. 2098 ciTypeFlow::Block* ciTypeFlow::work_list_next() { 2099 assert(!work_list_empty(), "work list must not be empty"); 2100 Block* next_block = _work_list; 2101 _work_list = next_block->next(); 2102 next_block->set_next(NULL); 2103 next_block->set_on_work_list(false); 2104 return next_block; 2105 } 2106 2107 // ------------------------------------------------------------------ 2108 // ciTypeFlow::add_to_work_list 2109 // 2110 // Add a basic block to our work list. 2111 // List is sorted by decreasing postorder sort (same as increasing RPO) 2112 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) { 2113 assert(!block->is_on_work_list(), "must not already be on work list"); 2114 2115 if (CITraceTypeFlow) { 2116 tty->print(">> Adding block "); 2117 block->print_value_on(tty); 2118 tty->print_cr(" to the work list : "); 2119 } 2120 2121 block->set_on_work_list(true); 2122 2123 // decreasing post order sort 2124 2125 Block* prev = NULL; 2126 Block* current = _work_list; 2127 int po = block->post_order(); 2128 while (current != NULL) { 2129 if (!current->has_post_order() || po > current->post_order()) 2130 break; 2131 prev = current; 2132 current = current->next(); 2133 } 2134 if (prev == NULL) { 2135 block->set_next(_work_list); 2136 _work_list = block; 2137 } else { 2138 block->set_next(current); 2139 prev->set_next(block); 2140 } 2141 2142 if (CITraceTypeFlow) { 2143 tty->cr(); 2144 } 2145 } 2146 2147 // ------------------------------------------------------------------ 2148 // ciTypeFlow::block_at 2149 // 2150 // Return the block beginning at bci which has a JsrSet compatible 2151 // with jsrs. 2152 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) { 2153 // First find the right ciBlock. 2154 if (CITraceTypeFlow) { 2155 tty->print(">> Requesting block for %d/", bci); 2156 jsrs->print_on(tty); 2157 tty->cr(); 2158 } 2159 2160 ciBlock* ciblk = _methodBlocks->block_containing(bci); 2161 assert(ciblk->start_bci() == bci, "bad ciBlock boundaries"); 2162 Block* block = get_block_for(ciblk->index(), jsrs, option); 2163 2164 assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result"); 2165 2166 if (CITraceTypeFlow) { 2167 if (block != NULL) { 2168 tty->print(">> Found block "); 2169 block->print_value_on(tty); 2170 tty->cr(); 2171 } else { 2172 tty->print_cr(">> No such block."); 2173 } 2174 } 2175 2176 return block; 2177 } 2178 2179 // ------------------------------------------------------------------ 2180 // ciTypeFlow::make_jsr_record 2181 // 2182 // Make a JsrRecord for a given (entry, return) pair, if such a record 2183 // does not already exist. 2184 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address, 2185 int return_address) { 2186 if (_jsr_records == NULL) { 2187 _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(), 2188 _jsr_count, 2189 0, 2190 NULL); 2191 } 2192 JsrRecord* record = NULL; 2193 int len = _jsr_records->length(); 2194 for (int i = 0; i < len; i++) { 2195 JsrRecord* record = _jsr_records->at(i); 2196 if (record->entry_address() == entry_address && 2197 record->return_address() == return_address) { 2198 return record; 2199 } 2200 } 2201 2202 record = new (arena()) JsrRecord(entry_address, return_address); 2203 _jsr_records->append(record); 2204 return record; 2205 } 2206 2207 // ------------------------------------------------------------------ 2208 // ciTypeFlow::flow_exceptions 2209 // 2210 // Merge the current state into all exceptional successors at the 2211 // current point in the code. 2212 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions, 2213 GrowableArray<ciInstanceKlass*>* exc_klasses, 2214 ciTypeFlow::StateVector* state) { 2215 int len = exceptions->length(); 2216 assert(exc_klasses->length() == len, "must have same length"); 2217 for (int i = 0; i < len; i++) { 2218 Block* block = exceptions->at(i); 2219 ciInstanceKlass* exception_klass = exc_klasses->at(i); 2220 2221 if (!exception_klass->is_loaded()) { 2222 // Do not compile any code for unloaded exception types. 2223 // Following compiler passes are responsible for doing this also. 2224 continue; 2225 } 2226 2227 if (block->meet_exception(exception_klass, state)) { 2228 // Block was modified and has PO. Add it to the work list. 2229 if (block->has_post_order() && 2230 !block->is_on_work_list()) { 2231 add_to_work_list(block); 2232 } 2233 } 2234 } 2235 } 2236 2237 // ------------------------------------------------------------------ 2238 // ciTypeFlow::flow_successors 2239 // 2240 // Merge the current state into all successors at the current point 2241 // in the code. 2242 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors, 2243 ciTypeFlow::StateVector* state) { 2244 int len = successors->length(); 2245 for (int i = 0; i < len; i++) { 2246 Block* block = successors->at(i); 2247 if (block->meet(state)) { 2248 // Block was modified and has PO. Add it to the work list. 2249 if (block->has_post_order() && 2250 !block->is_on_work_list()) { 2251 add_to_work_list(block); 2252 } 2253 } 2254 } 2255 } 2256 2257 // ------------------------------------------------------------------ 2258 // ciTypeFlow::can_trap 2259 // 2260 // Tells if a given instruction is able to generate an exception edge. 2261 bool ciTypeFlow::can_trap(ciBytecodeStream& str) { 2262 // Cf. GenerateOopMap::do_exception_edge. 2263 if (!Bytecodes::can_trap(str.cur_bc())) return false; 2264 2265 switch (str.cur_bc()) { 2266 // %%% FIXME: ldc of Class can generate an exception 2267 case Bytecodes::_ldc: 2268 case Bytecodes::_ldc_w: 2269 case Bytecodes::_ldc2_w: 2270 case Bytecodes::_aload_0: 2271 // These bytecodes can trap for rewriting. We need to assume that 2272 // they do not throw exceptions to make the monitor analysis work. 2273 return false; 2274 2275 case Bytecodes::_ireturn: 2276 case Bytecodes::_lreturn: 2277 case Bytecodes::_freturn: 2278 case Bytecodes::_dreturn: 2279 case Bytecodes::_areturn: 2280 case Bytecodes::_return: 2281 // We can assume the monitor stack is empty in this analysis. 2282 return false; 2283 2284 case Bytecodes::_monitorexit: 2285 // We can assume monitors are matched in this analysis. 2286 return false; 2287 2288 default: 2289 return true; 2290 } 2291 } 2292 2293 // ------------------------------------------------------------------ 2294 // ciTypeFlow::clone_loop_heads 2295 // 2296 // Clone the loop heads 2297 bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) { 2298 bool rslt = false; 2299 for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) { 2300 lp = iter.current(); 2301 Block* head = lp->head(); 2302 if (lp == loop_tree_root() || 2303 lp->is_irreducible() || 2304 !head->is_clonable_exit(lp)) 2305 continue; 2306 2307 // Avoid BoxLock merge. 2308 if (EliminateNestedLocks && head->has_monitorenter()) 2309 continue; 2310 2311 // check not already cloned 2312 if (head->backedge_copy_count() != 0) 2313 continue; 2314 2315 // Don't clone head of OSR loop to get correct types in start block. 2316 if (is_osr_flow() && head->start() == start_bci()) 2317 continue; 2318 2319 // check _no_ shared head below us 2320 Loop* ch; 2321 for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling()); 2322 if (ch != NULL) 2323 continue; 2324 2325 // Clone head 2326 Block* new_head = head->looping_succ(lp); 2327 Block* clone = clone_loop_head(lp, temp_vector, temp_set); 2328 // Update lp's info 2329 clone->set_loop(lp); 2330 lp->set_head(new_head); 2331 lp->set_tail(clone); 2332 // And move original head into outer loop 2333 head->set_loop(lp->parent()); 2334 2335 rslt = true; 2336 } 2337 return rslt; 2338 } 2339 2340 // ------------------------------------------------------------------ 2341 // ciTypeFlow::clone_loop_head 2342 // 2343 // Clone lp's head and replace tail's successors with clone. 2344 // 2345 // | 2346 // v 2347 // head <-> body 2348 // | 2349 // v 2350 // exit 2351 // 2352 // new_head 2353 // 2354 // | 2355 // v 2356 // head ----------\ 2357 // | | 2358 // | v 2359 // | clone <-> body 2360 // | | 2361 // | /--/ 2362 // | | 2363 // v v 2364 // exit 2365 // 2366 ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) { 2367 Block* head = lp->head(); 2368 Block* tail = lp->tail(); 2369 if (CITraceTypeFlow) { 2370 tty->print(">> Requesting clone of loop head "); head->print_value_on(tty); 2371 tty->print(" for predecessor "); tail->print_value_on(tty); 2372 tty->cr(); 2373 } 2374 Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy); 2375 assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges"); 2376 2377 assert(!clone->has_pre_order(), "just created"); 2378 clone->set_next_pre_order(); 2379 2380 // Insert clone after (orig) tail in reverse post order 2381 clone->set_rpo_next(tail->rpo_next()); 2382 tail->set_rpo_next(clone); 2383 2384 // tail->head becomes tail->clone 2385 for (SuccIter iter(tail); !iter.done(); iter.next()) { 2386 if (iter.succ() == head) { 2387 iter.set_succ(clone); 2388 // Update predecessor information 2389 head->predecessors()->remove(tail); 2390 clone->predecessors()->append(tail); 2391 } 2392 } 2393 flow_block(tail, temp_vector, temp_set); 2394 if (head == tail) { 2395 // For self-loops, clone->head becomes clone->clone 2396 flow_block(clone, temp_vector, temp_set); 2397 for (SuccIter iter(clone); !iter.done(); iter.next()) { 2398 if (iter.succ() == head) { 2399 iter.set_succ(clone); 2400 // Update predecessor information 2401 head->predecessors()->remove(clone); 2402 clone->predecessors()->append(clone); 2403 break; 2404 } 2405 } 2406 } 2407 flow_block(clone, temp_vector, temp_set); 2408 2409 return clone; 2410 } 2411 2412 // ------------------------------------------------------------------ 2413 // ciTypeFlow::flow_block 2414 // 2415 // Interpret the effects of the bytecodes on the incoming state 2416 // vector of a basic block. Push the changed state to succeeding 2417 // basic blocks. 2418 void ciTypeFlow::flow_block(ciTypeFlow::Block* block, 2419 ciTypeFlow::StateVector* state, 2420 ciTypeFlow::JsrSet* jsrs) { 2421 if (CITraceTypeFlow) { 2422 tty->print("\n>> ANALYZING BLOCK : "); 2423 tty->cr(); 2424 block->print_on(tty); 2425 } 2426 assert(block->has_pre_order(), "pre-order is assigned before 1st flow"); 2427 2428 int start = block->start(); 2429 int limit = block->limit(); 2430 int control = block->control(); 2431 if (control != ciBlock::fall_through_bci) { 2432 limit = control; 2433 } 2434 2435 // Grab the state from the current block. 2436 block->copy_state_into(state); 2437 state->def_locals()->clear(); 2438 2439 GrowableArray<Block*>* exceptions = block->exceptions(); 2440 GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses(); 2441 bool has_exceptions = exceptions->length() > 0; 2442 2443 bool exceptions_used = false; 2444 2445 ciBytecodeStream str(method()); 2446 str.reset_to_bci(start); 2447 Bytecodes::Code code; 2448 while ((code = str.next()) != ciBytecodeStream::EOBC() && 2449 str.cur_bci() < limit) { 2450 // Check for exceptional control flow from this point. 2451 if (has_exceptions && can_trap(str)) { 2452 flow_exceptions(exceptions, exc_klasses, state); 2453 exceptions_used = true; 2454 } 2455 // Apply the effects of the current bytecode to our state. 2456 bool res = state->apply_one_bytecode(&str); 2457 2458 // Watch for bailouts. 2459 if (failing()) return; 2460 2461 if (str.cur_bc() == Bytecodes::_monitorenter) { 2462 block->set_has_monitorenter(); 2463 } 2464 2465 if (res) { 2466 2467 // We have encountered a trap. Record it in this block. 2468 block->set_trap(state->trap_bci(), state->trap_index()); 2469 2470 if (CITraceTypeFlow) { 2471 tty->print_cr(">> Found trap"); 2472 block->print_on(tty); 2473 } 2474 2475 // Save set of locals defined in this block 2476 block->def_locals()->add(state->def_locals()); 2477 2478 // Record (no) successors. 2479 block->successors(&str, state, jsrs); 2480 2481 assert(!has_exceptions || exceptions_used, "Not removing exceptions"); 2482 2483 // Discontinue interpretation of this Block. 2484 return; 2485 } 2486 } 2487 2488 GrowableArray<Block*>* successors = NULL; 2489 if (control != ciBlock::fall_through_bci) { 2490 // Check for exceptional control flow from this point. 2491 if (has_exceptions && can_trap(str)) { 2492 flow_exceptions(exceptions, exc_klasses, state); 2493 exceptions_used = true; 2494 } 2495 2496 // Fix the JsrSet to reflect effect of the bytecode. 2497 block->copy_jsrs_into(jsrs); 2498 jsrs->apply_control(this, &str, state); 2499 2500 // Find successor edges based on old state and new JsrSet. 2501 successors = block->successors(&str, state, jsrs); 2502 2503 // Apply the control changes to the state. 2504 state->apply_one_bytecode(&str); 2505 } else { 2506 // Fall through control 2507 successors = block->successors(&str, NULL, NULL); 2508 } 2509 2510 // Save set of locals defined in this block 2511 block->def_locals()->add(state->def_locals()); 2512 2513 // Remove untaken exception paths 2514 if (!exceptions_used) 2515 exceptions->clear(); 2516 2517 // Pass our state to successors. 2518 flow_successors(successors, state); 2519 } 2520 2521 // ------------------------------------------------------------------ 2522 // ciTypeFlow::PostOrderLoops::next 2523 // 2524 // Advance to next loop tree using a postorder, left-to-right traversal. 2525 void ciTypeFlow::PostorderLoops::next() { 2526 assert(!done(), "must not be done."); 2527 if (_current->sibling() != NULL) { 2528 _current = _current->sibling(); 2529 while (_current->child() != NULL) { 2530 _current = _current->child(); 2531 } 2532 } else { 2533 _current = _current->parent(); 2534 } 2535 } 2536 2537 // ------------------------------------------------------------------ 2538 // ciTypeFlow::PreOrderLoops::next 2539 // 2540 // Advance to next loop tree using a preorder, left-to-right traversal. 2541 void ciTypeFlow::PreorderLoops::next() { 2542 assert(!done(), "must not be done."); 2543 if (_current->child() != NULL) { 2544 _current = _current->child(); 2545 } else if (_current->sibling() != NULL) { 2546 _current = _current->sibling(); 2547 } else { 2548 while (_current != _root && _current->sibling() == NULL) { 2549 _current = _current->parent(); 2550 } 2551 if (_current == _root) { 2552 _current = NULL; 2553 assert(done(), "must be done."); 2554 } else { 2555 assert(_current->sibling() != NULL, "must be more to do"); 2556 _current = _current->sibling(); 2557 } 2558 } 2559 } 2560 2561 // ------------------------------------------------------------------ 2562 // ciTypeFlow::Loop::sorted_merge 2563 // 2564 // Merge the branch lp into this branch, sorting on the loop head 2565 // pre_orders. Returns the leaf of the merged branch. 2566 // Child and sibling pointers will be setup later. 2567 // Sort is (looking from leaf towards the root) 2568 // descending on primary key: loop head's pre_order, and 2569 // ascending on secondary key: loop tail's pre_order. 2570 ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) { 2571 Loop* leaf = this; 2572 Loop* prev = NULL; 2573 Loop* current = leaf; 2574 while (lp != NULL) { 2575 int lp_pre_order = lp->head()->pre_order(); 2576 // Find insertion point for "lp" 2577 while (current != NULL) { 2578 if (current == lp) 2579 return leaf; // Already in list 2580 if (current->head()->pre_order() < lp_pre_order) 2581 break; 2582 if (current->head()->pre_order() == lp_pre_order && 2583 current->tail()->pre_order() > lp->tail()->pre_order()) { 2584 break; 2585 } 2586 prev = current; 2587 current = current->parent(); 2588 } 2589 Loop* next_lp = lp->parent(); // Save future list of items to insert 2590 // Insert lp before current 2591 lp->set_parent(current); 2592 if (prev != NULL) { 2593 prev->set_parent(lp); 2594 } else { 2595 leaf = lp; 2596 } 2597 prev = lp; // Inserted item is new prev[ious] 2598 lp = next_lp; // Next item to insert 2599 } 2600 return leaf; 2601 } 2602 2603 // ------------------------------------------------------------------ 2604 // ciTypeFlow::build_loop_tree 2605 // 2606 // Incrementally build loop tree. 2607 void ciTypeFlow::build_loop_tree(Block* blk) { 2608 assert(!blk->is_post_visited(), "precondition"); 2609 Loop* innermost = NULL; // merge of loop tree branches over all successors 2610 2611 for (SuccIter iter(blk); !iter.done(); iter.next()) { 2612 Loop* lp = NULL; 2613 Block* succ = iter.succ(); 2614 if (!succ->is_post_visited()) { 2615 // Found backedge since predecessor post visited, but successor is not 2616 assert(succ->pre_order() <= blk->pre_order(), "should be backedge"); 2617 2618 // Create a LoopNode to mark this loop. 2619 lp = new (arena()) Loop(succ, blk); 2620 if (succ->loop() == NULL) 2621 succ->set_loop(lp); 2622 // succ->loop will be updated to innermost loop on a later call, when blk==succ 2623 2624 } else { // Nested loop 2625 lp = succ->loop(); 2626 2627 // If succ is loop head, find outer loop. 2628 while (lp != NULL && lp->head() == succ) { 2629 lp = lp->parent(); 2630 } 2631 if (lp == NULL) { 2632 // Infinite loop, it's parent is the root 2633 lp = loop_tree_root(); 2634 } 2635 } 2636 2637 // Check for irreducible loop. 2638 // Successor has already been visited. If the successor's loop head 2639 // has already been post-visited, then this is another entry into the loop. 2640 while (lp->head()->is_post_visited() && lp != loop_tree_root()) { 2641 _has_irreducible_entry = true; 2642 lp->set_irreducible(succ); 2643 if (!succ->is_on_work_list()) { 2644 // Assume irreducible entries need more data flow 2645 add_to_work_list(succ); 2646 } 2647 Loop* plp = lp->parent(); 2648 if (plp == NULL) { 2649 // This only happens for some irreducible cases. The parent 2650 // will be updated during a later pass. 2651 break; 2652 } 2653 lp = plp; 2654 } 2655 2656 // Merge loop tree branch for all successors. 2657 innermost = innermost == NULL ? lp : innermost->sorted_merge(lp); 2658 2659 } // end loop 2660 2661 if (innermost == NULL) { 2662 assert(blk->successors()->length() == 0, "CFG exit"); 2663 blk->set_loop(loop_tree_root()); 2664 } else if (innermost->head() == blk) { 2665 // If loop header, complete the tree pointers 2666 if (blk->loop() != innermost) { 2667 #ifdef ASSERT 2668 assert(blk->loop()->head() == innermost->head(), "same head"); 2669 Loop* dl; 2670 for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent()); 2671 assert(dl == blk->loop(), "blk->loop() already in innermost list"); 2672 #endif 2673 blk->set_loop(innermost); 2674 } 2675 innermost->def_locals()->add(blk->def_locals()); 2676 Loop* l = innermost; 2677 Loop* p = l->parent(); 2678 while (p && l->head() == blk) { 2679 l->set_sibling(p->child()); // Put self on parents 'next child' 2680 p->set_child(l); // Make self the first child of parent 2681 p->def_locals()->add(l->def_locals()); 2682 l = p; // Walk up the parent chain 2683 p = l->parent(); 2684 } 2685 } else { 2686 blk->set_loop(innermost); 2687 innermost->def_locals()->add(blk->def_locals()); 2688 } 2689 } 2690 2691 // ------------------------------------------------------------------ 2692 // ciTypeFlow::Loop::contains 2693 // 2694 // Returns true if lp is nested loop. 2695 bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const { 2696 assert(lp != NULL, ""); 2697 if (this == lp || head() == lp->head()) return true; 2698 int depth1 = depth(); 2699 int depth2 = lp->depth(); 2700 if (depth1 > depth2) 2701 return false; 2702 while (depth1 < depth2) { 2703 depth2--; 2704 lp = lp->parent(); 2705 } 2706 return this == lp; 2707 } 2708 2709 // ------------------------------------------------------------------ 2710 // ciTypeFlow::Loop::depth 2711 // 2712 // Loop depth 2713 int ciTypeFlow::Loop::depth() const { 2714 int dp = 0; 2715 for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent()) 2716 dp++; 2717 return dp; 2718 } 2719 2720 #ifndef PRODUCT 2721 // ------------------------------------------------------------------ 2722 // ciTypeFlow::Loop::print 2723 void ciTypeFlow::Loop::print(outputStream* st, int indent) const { 2724 for (int i = 0; i < indent; i++) st->print(" "); 2725 st->print("%d<-%d %s", 2726 is_root() ? 0 : this->head()->pre_order(), 2727 is_root() ? 0 : this->tail()->pre_order(), 2728 is_irreducible()?" irr":""); 2729 st->print(" defs: "); 2730 def_locals()->print_on(st, _head->outer()->method()->max_locals()); 2731 st->cr(); 2732 for (Loop* ch = child(); ch != NULL; ch = ch->sibling()) 2733 ch->print(st, indent+2); 2734 } 2735 #endif 2736 2737 // ------------------------------------------------------------------ 2738 // ciTypeFlow::df_flow_types 2739 // 2740 // Perform the depth first type flow analysis. Helper for flow_types. 2741 void ciTypeFlow::df_flow_types(Block* start, 2742 bool do_flow, 2743 StateVector* temp_vector, 2744 JsrSet* temp_set) { 2745 int dft_len = 100; 2746 GrowableArray<Block*> stk(dft_len); 2747 2748 ciBlock* dummy = _methodBlocks->make_dummy_block(); 2749 JsrSet* root_set = new JsrSet(NULL, 0); 2750 Block* root_head = new (arena()) Block(this, dummy, root_set); 2751 Block* root_tail = new (arena()) Block(this, dummy, root_set); 2752 root_head->set_pre_order(0); 2753 root_head->set_post_order(0); 2754 root_tail->set_pre_order(max_jint); 2755 root_tail->set_post_order(max_jint); 2756 set_loop_tree_root(new (arena()) Loop(root_head, root_tail)); 2757 2758 stk.push(start); 2759 2760 _next_pre_order = 0; // initialize pre_order counter 2761 _rpo_list = NULL; 2762 int next_po = 0; // initialize post_order counter 2763 2764 // Compute RPO and the control flow graph 2765 int size; 2766 while ((size = stk.length()) > 0) { 2767 Block* blk = stk.top(); // Leave node on stack 2768 if (!blk->is_visited()) { 2769 // forward arc in graph 2770 assert (!blk->has_pre_order(), ""); 2771 blk->set_next_pre_order(); 2772 2773 if (_next_pre_order >= (int)Compile::current()->max_node_limit() / 2) { 2774 // Too many basic blocks. Bail out. 2775 // This can happen when try/finally constructs are nested to depth N, 2776 // and there is O(2**N) cloning of jsr bodies. See bug 4697245! 2777 // "MaxNodeLimit / 2" is used because probably the parser will 2778 // generate at least twice that many nodes and bail out. 2779 record_failure("too many basic blocks"); 2780 return; 2781 } 2782 if (do_flow) { 2783 flow_block(blk, temp_vector, temp_set); 2784 if (failing()) return; // Watch for bailouts. 2785 } 2786 } else if (!blk->is_post_visited()) { 2787 // cross or back arc 2788 for (SuccIter iter(blk); !iter.done(); iter.next()) { 2789 Block* succ = iter.succ(); 2790 if (!succ->is_visited()) { 2791 stk.push(succ); 2792 } 2793 } 2794 if (stk.length() == size) { 2795 // There were no additional children, post visit node now 2796 stk.pop(); // Remove node from stack 2797 2798 build_loop_tree(blk); 2799 blk->set_post_order(next_po++); // Assign post order 2800 prepend_to_rpo_list(blk); 2801 assert(blk->is_post_visited(), ""); 2802 2803 if (blk->is_loop_head() && !blk->is_on_work_list()) { 2804 // Assume loop heads need more data flow 2805 add_to_work_list(blk); 2806 } 2807 } 2808 } else { 2809 stk.pop(); // Remove post-visited node from stack 2810 } 2811 } 2812 } 2813 2814 // ------------------------------------------------------------------ 2815 // ciTypeFlow::flow_types 2816 // 2817 // Perform the type flow analysis, creating and cloning Blocks as 2818 // necessary. 2819 void ciTypeFlow::flow_types() { 2820 ResourceMark rm; 2821 StateVector* temp_vector = new StateVector(this); 2822 JsrSet* temp_set = new JsrSet(NULL, 16); 2823 2824 // Create the method entry block. 2825 Block* start = block_at(start_bci(), temp_set); 2826 2827 // Load the initial state into it. 2828 const StateVector* start_state = get_start_state(); 2829 if (failing()) return; 2830 start->meet(start_state); 2831 2832 // Depth first visit 2833 df_flow_types(start, true /*do flow*/, temp_vector, temp_set); 2834 2835 if (failing()) return; 2836 assert(_rpo_list == start, "must be start"); 2837 2838 // Any loops found? 2839 if (loop_tree_root()->child() != NULL && 2840 env()->comp_level() >= CompLevel_full_optimization) { 2841 // Loop optimizations are not performed on Tier1 compiles. 2842 2843 bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set); 2844 2845 // If some loop heads were cloned, recompute postorder and loop tree 2846 if (changed) { 2847 loop_tree_root()->set_child(NULL); 2848 for (Block* blk = _rpo_list; blk != NULL;) { 2849 Block* next = blk->rpo_next(); 2850 blk->df_init(); 2851 blk = next; 2852 } 2853 df_flow_types(start, false /*no flow*/, temp_vector, temp_set); 2854 } 2855 } 2856 2857 if (CITraceTypeFlow) { 2858 tty->print_cr("\nLoop tree"); 2859 loop_tree_root()->print(); 2860 } 2861 2862 // Continue flow analysis until fixed point reached 2863 2864 debug_only(int max_block = _next_pre_order;) 2865 2866 while (!work_list_empty()) { 2867 Block* blk = work_list_next(); 2868 assert (blk->has_post_order(), "post order assigned above"); 2869 2870 flow_block(blk, temp_vector, temp_set); 2871 2872 assert (max_block == _next_pre_order, "no new blocks"); 2873 assert (!failing(), "no more bailouts"); 2874 } 2875 } 2876 2877 // ------------------------------------------------------------------ 2878 // ciTypeFlow::map_blocks 2879 // 2880 // Create the block map, which indexes blocks in reverse post-order. 2881 void ciTypeFlow::map_blocks() { 2882 assert(_block_map == NULL, "single initialization"); 2883 int block_ct = _next_pre_order; 2884 _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct); 2885 assert(block_ct == block_count(), ""); 2886 2887 Block* blk = _rpo_list; 2888 for (int m = 0; m < block_ct; m++) { 2889 int rpo = blk->rpo(); 2890 assert(rpo == m, "should be sequential"); 2891 _block_map[rpo] = blk; 2892 blk = blk->rpo_next(); 2893 } 2894 assert(blk == NULL, "should be done"); 2895 2896 for (int j = 0; j < block_ct; j++) { 2897 assert(_block_map[j] != NULL, "must not drop any blocks"); 2898 Block* block = _block_map[j]; 2899 // Remove dead blocks from successor lists: 2900 for (int e = 0; e <= 1; e++) { 2901 GrowableArray<Block*>* l = e? block->exceptions(): block->successors(); 2902 for (int k = 0; k < l->length(); k++) { 2903 Block* s = l->at(k); 2904 if (!s->has_post_order()) { 2905 if (CITraceTypeFlow) { 2906 tty->print("Removing dead %s successor of #%d: ", (e? "exceptional": "normal"), block->pre_order()); 2907 s->print_value_on(tty); 2908 tty->cr(); 2909 } 2910 l->remove(s); 2911 --k; 2912 } 2913 } 2914 } 2915 } 2916 } 2917 2918 // ------------------------------------------------------------------ 2919 // ciTypeFlow::get_block_for 2920 // 2921 // Find a block with this ciBlock which has a compatible JsrSet. 2922 // If no such block exists, create it, unless the option is no_create. 2923 // If the option is create_backedge_copy, always create a fresh backedge copy. 2924 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) { 2925 Arena* a = arena(); 2926 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex]; 2927 if (blocks == NULL) { 2928 // Query only? 2929 if (option == no_create) return NULL; 2930 2931 // Allocate the growable array. 2932 blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL); 2933 _idx_to_blocklist[ciBlockIndex] = blocks; 2934 } 2935 2936 if (option != create_backedge_copy) { 2937 int len = blocks->length(); 2938 for (int i = 0; i < len; i++) { 2939 Block* block = blocks->at(i); 2940 if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) { 2941 return block; 2942 } 2943 } 2944 } 2945 2946 // Query only? 2947 if (option == no_create) return NULL; 2948 2949 // We did not find a compatible block. Create one. 2950 Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs); 2951 if (option == create_backedge_copy) new_block->set_backedge_copy(true); 2952 blocks->append(new_block); 2953 return new_block; 2954 } 2955 2956 // ------------------------------------------------------------------ 2957 // ciTypeFlow::backedge_copy_count 2958 // 2959 int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const { 2960 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex]; 2961 2962 if (blocks == NULL) { 2963 return 0; 2964 } 2965 2966 int count = 0; 2967 int len = blocks->length(); 2968 for (int i = 0; i < len; i++) { 2969 Block* block = blocks->at(i); 2970 if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) { 2971 count++; 2972 } 2973 } 2974 2975 return count; 2976 } 2977 2978 // ------------------------------------------------------------------ 2979 // ciTypeFlow::do_flow 2980 // 2981 // Perform type inference flow analysis. 2982 void ciTypeFlow::do_flow() { 2983 if (CITraceTypeFlow) { 2984 tty->print_cr("\nPerforming flow analysis on method"); 2985 method()->print(); 2986 if (is_osr_flow()) tty->print(" at OSR bci %d", start_bci()); 2987 tty->cr(); 2988 method()->print_codes(); 2989 } 2990 if (CITraceTypeFlow) { 2991 tty->print_cr("Initial CI Blocks"); 2992 print_on(tty); 2993 } 2994 flow_types(); 2995 // Watch for bailouts. 2996 if (failing()) { 2997 return; 2998 } 2999 3000 map_blocks(); 3001 3002 if (CIPrintTypeFlow || CITraceTypeFlow) { 3003 rpo_print_on(tty); 3004 } 3005 } 3006 3007 // ------------------------------------------------------------------ 3008 // ciTypeFlow::is_dominated_by 3009 // 3010 // Determine if the instruction at bci is dominated by the instruction at dom_bci. 3011 bool ciTypeFlow::is_dominated_by(int bci, int dom_bci) { 3012 assert(!method()->has_jsrs(), "jsrs are not supported"); 3013 3014 ResourceMark rm; 3015 JsrSet* jsrs = new ciTypeFlow::JsrSet(NULL); 3016 int index = _methodBlocks->block_containing(bci)->index(); 3017 int dom_index = _methodBlocks->block_containing(dom_bci)->index(); 3018 Block* block = get_block_for(index, jsrs, ciTypeFlow::no_create); 3019 Block* dom_block = get_block_for(dom_index, jsrs, ciTypeFlow::no_create); 3020 3021 // Start block dominates all other blocks 3022 if (start_block()->rpo() == dom_block->rpo()) { 3023 return true; 3024 } 3025 3026 // Dominated[i] is true if block i is dominated by dom_block 3027 int num_blocks = block_count(); 3028 bool* dominated = NEW_RESOURCE_ARRAY(bool, num_blocks); 3029 for (int i = 0; i < num_blocks; ++i) { 3030 dominated[i] = true; 3031 } 3032 dominated[start_block()->rpo()] = false; 3033 3034 // Iterative dominator algorithm 3035 bool changed = true; 3036 while (changed) { 3037 changed = false; 3038 // Use reverse postorder iteration 3039 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) { 3040 if (blk->is_start()) { 3041 // Ignore start block 3042 continue; 3043 } 3044 // The block is dominated if it is the dominating block 3045 // itself or if all predecessors are dominated. 3046 int index = blk->rpo(); 3047 bool dom = (index == dom_block->rpo()); 3048 if (!dom) { 3049 // Check if all predecessors are dominated 3050 dom = true; 3051 for (int i = 0; i < blk->predecessors()->length(); ++i) { 3052 Block* pred = blk->predecessors()->at(i); 3053 if (!dominated[pred->rpo()]) { 3054 dom = false; 3055 break; 3056 } 3057 } 3058 } 3059 // Update dominator information 3060 if (dominated[index] != dom) { 3061 changed = true; 3062 dominated[index] = dom; 3063 } 3064 } 3065 } 3066 // block dominated by dom_block? 3067 return dominated[block->rpo()]; 3068 } 3069 3070 // ------------------------------------------------------------------ 3071 // ciTypeFlow::record_failure() 3072 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv. 3073 // This is required because there is not a 1-1 relation between the ciEnv and 3074 // the TypeFlow passes within a compilation task. For example, if the compiler 3075 // is considering inlining a method, it will request a TypeFlow. If that fails, 3076 // the compilation as a whole may continue without the inlining. Some TypeFlow 3077 // requests are not optional; if they fail the requestor is responsible for 3078 // copying the failure reason up to the ciEnv. (See Parse::Parse.) 3079 void ciTypeFlow::record_failure(const char* reason) { 3080 if (env()->log() != NULL) { 3081 env()->log()->elem("failure reason='%s' phase='typeflow'", reason); 3082 } 3083 if (_failure_reason == NULL) { 3084 // Record the first failure reason. 3085 _failure_reason = reason; 3086 } 3087 } 3088 3089 ciType* ciTypeFlow::mark_as_never_null(ciType* type) { 3090 // Wrap the type to carry the information that it is never null 3091 return new (arena()) ciWrapper(type, /* never_null */ true); 3092 } 3093 3094 #ifndef PRODUCT 3095 // ------------------------------------------------------------------ 3096 // ciTypeFlow::print_on 3097 void ciTypeFlow::print_on(outputStream* st) const { 3098 // Walk through CI blocks 3099 st->print_cr("********************************************************"); 3100 st->print ("TypeFlow for "); 3101 method()->name()->print_symbol_on(st); 3102 int limit_bci = code_size(); 3103 st->print_cr(" %d bytes", limit_bci); 3104 ciMethodBlocks *mblks = _methodBlocks; 3105 ciBlock* current = NULL; 3106 for (int bci = 0; bci < limit_bci; bci++) { 3107 ciBlock* blk = mblks->block_containing(bci); 3108 if (blk != NULL && blk != current) { 3109 current = blk; 3110 current->print_on(st); 3111 3112 GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()]; 3113 int num_blocks = (blocks == NULL) ? 0 : blocks->length(); 3114 3115 if (num_blocks == 0) { 3116 st->print_cr(" No Blocks"); 3117 } else { 3118 for (int i = 0; i < num_blocks; i++) { 3119 Block* block = blocks->at(i); 3120 block->print_on(st); 3121 } 3122 } 3123 st->print_cr("--------------------------------------------------------"); 3124 st->cr(); 3125 } 3126 } 3127 st->print_cr("********************************************************"); 3128 st->cr(); 3129 } 3130 3131 void ciTypeFlow::rpo_print_on(outputStream* st) const { 3132 st->print_cr("********************************************************"); 3133 st->print ("TypeFlow for "); 3134 method()->name()->print_symbol_on(st); 3135 int limit_bci = code_size(); 3136 st->print_cr(" %d bytes", limit_bci); 3137 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) { 3138 blk->print_on(st); 3139 st->print_cr("--------------------------------------------------------"); 3140 st->cr(); 3141 } 3142 st->print_cr("********************************************************"); 3143 st->cr(); 3144 } 3145 #endif