1 /* 2 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "ci/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 "compiler/compileLog.hpp" 35 #include "interpreter/bytecode.hpp" 36 #include "interpreter/bytecodes.hpp" 37 #include "memory/allocation.inline.hpp" 38 #include "memory/resourceArea.hpp" 39 #include "oops/oop.inline.hpp" 40 #include "opto/compile.hpp" 41 #include "opto/node.hpp" 42 #include "runtime/deoptimization.hpp" 43 #include "utilities/growableArray.hpp" 44 45 // ciTypeFlow::JsrSet 46 // 47 // A JsrSet represents some set of JsrRecords. This class 48 // is used to record a set of all jsr routines which we permit 49 // execution to return (ret) from. 50 // 51 // During abstract interpretation, JsrSets are used to determine 52 // whether two paths which reach a given block are unique, and 53 // should be cloned apart, or are compatible, and should merge 54 // together. 55 56 // ------------------------------------------------------------------ 57 // ciTypeFlow::JsrSet::JsrSet 58 ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) { 59 if (arena != NULL) { 60 // Allocate growable array in Arena. 61 _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL); 62 } else { 63 // Allocate growable array in current ResourceArea. 64 _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false); 65 } 66 } 67 68 // ------------------------------------------------------------------ 69 // ciTypeFlow::JsrSet::copy_into 70 void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) { 71 int len = size(); 72 jsrs->_set->clear(); 73 for (int i = 0; i < len; i++) { 74 jsrs->_set->append(_set->at(i)); 75 } 76 } 77 78 // ------------------------------------------------------------------ 79 // ciTypeFlow::JsrSet::is_compatible_with 80 // 81 // !!!! MISGIVINGS ABOUT THIS... disregard 82 // 83 // Is this JsrSet compatible with some other JsrSet? 84 // 85 // In set-theoretic terms, a JsrSet can be viewed as a partial function 86 // from entry addresses to return addresses. Two JsrSets A and B are 87 // compatible iff 88 // 89 // For any x, 90 // A(x) defined and B(x) defined implies A(x) == B(x) 91 // 92 // Less formally, two JsrSets are compatible when they have identical 93 // return addresses for any entry addresses they share in common. 94 bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) { 95 // Walk through both sets in parallel. If the same entry address 96 // appears in both sets, then the return address must match for 97 // the sets to be compatible. 98 int size1 = size(); 99 int size2 = other->size(); 100 101 // Special case. If nothing is on the jsr stack, then there can 102 // be no ret. 103 if (size2 == 0) { 104 return true; 105 } else if (size1 != size2) { 106 return false; 107 } else { 108 for (int i = 0; i < size1; i++) { 109 JsrRecord* record1 = record_at(i); 110 JsrRecord* record2 = other->record_at(i); 111 if (record1->entry_address() != record2->entry_address() || 112 record1->return_address() != record2->return_address()) { 113 return false; 114 } 115 } 116 return true; 117 } 118 119 #if 0 120 int pos1 = 0; 121 int pos2 = 0; 122 int size1 = size(); 123 int size2 = other->size(); 124 while (pos1 < size1 && pos2 < size2) { 125 JsrRecord* record1 = record_at(pos1); 126 JsrRecord* record2 = other->record_at(pos2); 127 int entry1 = record1->entry_address(); 128 int entry2 = record2->entry_address(); 129 if (entry1 < entry2) { 130 pos1++; 131 } else if (entry1 > entry2) { 132 pos2++; 133 } else { 134 if (record1->return_address() == record2->return_address()) { 135 pos1++; 136 pos2++; 137 } else { 138 // These two JsrSets are incompatible. 139 return false; 140 } 141 } 142 } 143 // The two JsrSets agree. 144 return true; 145 #endif 146 } 147 148 // ------------------------------------------------------------------ 149 // ciTypeFlow::JsrSet::insert_jsr_record 150 // 151 // Insert the given JsrRecord into the JsrSet, maintaining the order 152 // of the set and replacing any element with the same entry address. 153 void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) { 154 int len = size(); 155 int entry = record->entry_address(); 156 int pos = 0; 157 for ( ; pos < len; pos++) { 158 JsrRecord* current = record_at(pos); 159 if (entry == current->entry_address()) { 160 // Stomp over this entry. 161 _set->at_put(pos, record); 162 assert(size() == len, "must be same size"); 163 return; 164 } else if (entry < current->entry_address()) { 165 break; 166 } 167 } 168 169 // Insert the record into the list. 170 JsrRecord* swap = record; 171 JsrRecord* temp = NULL; 172 for ( ; pos < len; pos++) { 173 temp = _set->at(pos); 174 _set->at_put(pos, swap); 175 swap = temp; 176 } 177 _set->append(swap); 178 assert(size() == len+1, "must be larger"); 179 } 180 181 // ------------------------------------------------------------------ 182 // ciTypeFlow::JsrSet::remove_jsr_record 183 // 184 // Remove the JsrRecord with the given return address from the JsrSet. 185 void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) { 186 int len = size(); 187 for (int i = 0; i < len; i++) { 188 if (record_at(i)->return_address() == return_address) { 189 // We have found the proper entry. Remove it from the 190 // JsrSet and exit. 191 for (int j = i+1; j < len ; j++) { 192 _set->at_put(j-1, _set->at(j)); 193 } 194 _set->trunc_to(len-1); 195 assert(size() == len-1, "must be smaller"); 196 return; 197 } 198 } 199 assert(false, "verify: returning from invalid subroutine"); 200 } 201 202 // ------------------------------------------------------------------ 203 // ciTypeFlow::JsrSet::apply_control 204 // 205 // Apply the effect of a control-flow bytecode on the JsrSet. The 206 // only bytecodes that modify the JsrSet are jsr and ret. 207 void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer, 208 ciBytecodeStream* str, 209 ciTypeFlow::StateVector* state) { 210 Bytecodes::Code code = str->cur_bc(); 211 if (code == Bytecodes::_jsr) { 212 JsrRecord* record = 213 analyzer->make_jsr_record(str->get_dest(), str->next_bci()); 214 insert_jsr_record(record); 215 } else if (code == Bytecodes::_jsr_w) { 216 JsrRecord* record = 217 analyzer->make_jsr_record(str->get_far_dest(), str->next_bci()); 218 insert_jsr_record(record); 219 } else if (code == Bytecodes::_ret) { 220 Cell local = state->local(str->get_index()); 221 ciType* return_address = state->type_at(local); 222 assert(return_address->is_return_address(), "verify: wrong type"); 223 if (size() == 0) { 224 // Ret-state underflow: Hit a ret w/o any previous jsrs. Bail out. 225 // This can happen when a loop is inside a finally clause (4614060). 226 analyzer->record_failure("OSR in finally clause"); 227 return; 228 } 229 remove_jsr_record(return_address->as_return_address()->bci()); 230 } 231 } 232 233 #ifndef PRODUCT 234 // ------------------------------------------------------------------ 235 // ciTypeFlow::JsrSet::print_on 236 void ciTypeFlow::JsrSet::print_on(outputStream* st) const { 237 st->print("{ "); 238 int num_elements = size(); 239 if (num_elements > 0) { 240 int i = 0; 241 for( ; i < num_elements - 1; i++) { 242 _set->at(i)->print_on(st); 243 st->print(", "); 244 } 245 _set->at(i)->print_on(st); 246 st->print(" "); 247 } 248 st->print("}"); 249 } 250 #endif 251 252 // ciTypeFlow::StateVector 253 // 254 // A StateVector summarizes the type information at some point in 255 // the program. 256 257 // ------------------------------------------------------------------ 258 // ciTypeFlow::StateVector::type_meet 259 // 260 // Meet two types. 261 // 262 // The semi-lattice of types use by this analysis are modeled on those 263 // of the verifier. The lattice is as follows: 264 // 265 // top_type() >= all non-extremal types >= bottom_type 266 // and 267 // Every primitive type is comparable only with itself. The meet of 268 // reference types is determined by their kind: instance class, 269 // interface, or array class. The meet of two types of the same 270 // kind is their least common ancestor. The meet of two types of 271 // different kinds is always java.lang.Object. 272 ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) { 273 assert(t1 != t2, "checked in caller"); 274 if (t1->equals(top_type())) { 275 return t2; 276 } else if (t2->equals(top_type())) { 277 return t1; 278 } else if (t1->is_primitive_type() || t2->is_primitive_type()) { 279 // Special case null_type. null_type meet any reference type T 280 // is T. null_type meet null_type is null_type. 281 if (t1->equals(null_type())) { 282 if (!t2->is_primitive_type() || t2->equals(null_type())) { 283 return t2; 284 } 285 } else if (t2->equals(null_type())) { 286 if (!t1->is_primitive_type()) { 287 return t1; 288 } 289 } 290 291 // At least one of the two types is a non-top primitive type. 292 // The other type is not equal to it. Fall to bottom. 293 return bottom_type(); 294 } else { 295 // Both types are non-top non-primitive types. That is, 296 // both types are either instanceKlasses or arrayKlasses. 297 ciKlass* object_klass = analyzer->env()->Object_klass(); 298 ciKlass* k1 = t1->as_klass(); 299 ciKlass* k2 = t2->as_klass(); 300 if (k1->equals(object_klass) || k2->equals(object_klass)) { 301 return object_klass; 302 } else if (!k1->is_loaded() || !k2->is_loaded()) { 303 // Unloaded classes fall to java.lang.Object at a merge. 304 return object_klass; 305 } else if (k1->is_interface() != k2->is_interface()) { 306 // When an interface meets a non-interface, we get Object; 307 // This is what the verifier does. 308 return object_klass; 309 } else if (k1->is_array_klass() || k2->is_array_klass()) { 310 // When an array meets a non-array, we get Object. 311 // When objArray meets typeArray, we also get Object. 312 // And when typeArray meets different typeArray, we again get Object. 313 // But when objArray meets objArray, we look carefully at element types. 314 if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) { 315 // Meet the element types, then construct the corresponding array type. 316 ciKlass* elem1 = k1->as_obj_array_klass()->element_klass(); 317 ciKlass* elem2 = k2->as_obj_array_klass()->element_klass(); 318 ciKlass* elem = type_meet_internal(elem1, elem2, analyzer)->as_klass(); 319 // Do an easy shortcut if one type is a super of the other. 320 if (elem == elem1) { 321 assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK"); 322 return k1; 323 } else if (elem == elem2) { 324 assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK"); 325 return k2; 326 } else { 327 return ciObjArrayKlass::make(elem); 328 } 329 } else { 330 return object_klass; 331 } 332 } else { 333 // Must be two plain old instance klasses. 334 assert(k1->is_instance_klass(), "previous cases handle non-instances"); 335 assert(k2->is_instance_klass(), "previous cases handle non-instances"); 336 return k1->least_common_ancestor(k2); 337 } 338 } 339 } 340 341 342 // ------------------------------------------------------------------ 343 // ciTypeFlow::StateVector::StateVector 344 // 345 // Build a new state vector 346 ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) { 347 _outer = analyzer; 348 _stack_size = -1; 349 _monitor_count = -1; 350 // Allocate the _types array 351 int max_cells = analyzer->max_cells(); 352 _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells); 353 for (int i=0; i<max_cells; i++) { 354 _types[i] = top_type(); 355 } 356 _trap_bci = -1; 357 _trap_index = 0; 358 _def_locals.clear(); 359 } 360 361 362 // ------------------------------------------------------------------ 363 // ciTypeFlow::get_start_state 364 // 365 // Set this vector to the method entry state. 366 const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() { 367 StateVector* state = new StateVector(this); 368 if (is_osr_flow()) { 369 ciTypeFlow* non_osr_flow = method()->get_flow_analysis(); 370 if (non_osr_flow->failing()) { 371 record_failure(non_osr_flow->failure_reason()); 372 return NULL; 373 } 374 JsrSet* jsrs = new JsrSet(NULL, 16); 375 Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs); 376 if (non_osr_block == NULL) { 377 record_failure("cannot reach OSR point"); 378 return NULL; 379 } 380 // load up the non-OSR state at this point 381 non_osr_block->copy_state_into(state); 382 int non_osr_start = non_osr_block->start(); 383 if (non_osr_start != start_bci()) { 384 // must flow forward from it 385 if (CITraceTypeFlow) { 386 tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start); 387 } 388 Block* block = block_at(non_osr_start, jsrs); 389 assert(block->limit() == start_bci(), "must flow forward to start"); 390 flow_block(block, state, jsrs); 391 } 392 return state; 393 // Note: The code below would be an incorrect for an OSR flow, 394 // even if it were possible for an OSR entry point to be at bci zero. 395 } 396 // "Push" the method signature into the first few locals. 397 state->set_stack_size(-max_locals()); 398 if (!method()->is_static()) { 399 state->push(method()->holder()); 400 assert(state->tos() == state->local(0), ""); 401 } 402 for (ciSignatureStream str(method()->signature()); 403 !str.at_return_type(); 404 str.next()) { 405 state->push_translate(str.type()); 406 } 407 // Set the rest of the locals to bottom. 408 Cell cell = state->next_cell(state->tos()); 409 state->set_stack_size(0); 410 int limit = state->limit_cell(); 411 for (; cell < limit; cell = state->next_cell(cell)) { 412 state->set_type_at(cell, state->bottom_type()); 413 } 414 // Lock an object, if necessary. 415 state->set_monitor_count(method()->is_synchronized() ? 1 : 0); 416 return state; 417 } 418 419 // ------------------------------------------------------------------ 420 // ciTypeFlow::StateVector::copy_into 421 // 422 // Copy our value into some other StateVector 423 void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy) 424 const { 425 copy->set_stack_size(stack_size()); 426 copy->set_monitor_count(monitor_count()); 427 Cell limit = limit_cell(); 428 for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 429 copy->set_type_at(c, type_at(c)); 430 } 431 } 432 433 // ------------------------------------------------------------------ 434 // ciTypeFlow::StateVector::meet 435 // 436 // Meets this StateVector with another, destructively modifying this 437 // one. Returns true if any modification takes place. 438 bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) { 439 if (monitor_count() == -1) { 440 set_monitor_count(incoming->monitor_count()); 441 } 442 assert(monitor_count() == incoming->monitor_count(), "monitors must match"); 443 444 if (stack_size() == -1) { 445 set_stack_size(incoming->stack_size()); 446 Cell limit = limit_cell(); 447 #ifdef ASSERT 448 { for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 449 assert(type_at(c) == top_type(), ""); 450 } } 451 #endif 452 // Make a simple copy of the incoming state. 453 for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 454 set_type_at(c, incoming->type_at(c)); 455 } 456 return true; // it is always different the first time 457 } 458 #ifdef ASSERT 459 if (stack_size() != incoming->stack_size()) { 460 _outer->method()->print_codes(); 461 tty->print_cr("!!!! Stack size conflict"); 462 tty->print_cr("Current state:"); 463 print_on(tty); 464 tty->print_cr("Incoming state:"); 465 ((StateVector*)incoming)->print_on(tty); 466 } 467 #endif 468 assert(stack_size() == incoming->stack_size(), "sanity"); 469 470 bool different = false; 471 Cell limit = limit_cell(); 472 for (Cell c = start_cell(); c < limit; c = next_cell(c)) { 473 ciType* t1 = type_at(c); 474 ciType* t2 = incoming->type_at(c); 475 if (!t1->equals(t2)) { 476 ciType* new_type = type_meet(t1, t2); 477 if (!t1->equals(new_type)) { 478 set_type_at(c, new_type); 479 different = true; 480 } 481 } 482 } 483 return different; 484 } 485 486 // ------------------------------------------------------------------ 487 // ciTypeFlow::StateVector::meet_exception 488 // 489 // Meets this StateVector with another, destructively modifying this 490 // one. The incoming state is coming via an exception. Returns true 491 // if any modification takes place. 492 bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc, 493 const ciTypeFlow::StateVector* incoming) { 494 if (monitor_count() == -1) { 495 set_monitor_count(incoming->monitor_count()); 496 } 497 assert(monitor_count() == incoming->monitor_count(), "monitors must match"); 498 499 if (stack_size() == -1) { 500 set_stack_size(1); 501 } 502 503 assert(stack_size() == 1, "must have one-element stack"); 504 505 bool different = false; 506 507 // Meet locals from incoming array. 508 Cell limit = local(_outer->max_locals()-1); 509 for (Cell c = start_cell(); c <= limit; c = next_cell(c)) { 510 ciType* t1 = type_at(c); 511 ciType* t2 = incoming->type_at(c); 512 if (!t1->equals(t2)) { 513 ciType* new_type = type_meet(t1, t2); 514 if (!t1->equals(new_type)) { 515 set_type_at(c, new_type); 516 different = true; 517 } 518 } 519 } 520 521 // Handle stack separately. When an exception occurs, the 522 // only stack entry is the exception instance. 523 ciType* tos_type = type_at_tos(); 524 if (!tos_type->equals(exc)) { 525 ciType* new_type = type_meet(tos_type, exc); 526 if (!tos_type->equals(new_type)) { 527 set_type_at_tos(new_type); 528 different = true; 529 } 530 } 531 532 return different; 533 } 534 535 // ------------------------------------------------------------------ 536 // ciTypeFlow::StateVector::push_translate 537 void ciTypeFlow::StateVector::push_translate(ciType* type) { 538 BasicType basic_type = type->basic_type(); 539 if (basic_type == T_BOOLEAN || basic_type == T_CHAR || 540 basic_type == T_BYTE || basic_type == T_SHORT) { 541 push_int(); 542 } else { 543 push(type); 544 if (type->is_two_word()) { 545 push(half_type(type)); 546 } 547 } 548 } 549 550 // ------------------------------------------------------------------ 551 // ciTypeFlow::StateVector::do_aaload 552 void ciTypeFlow::StateVector::do_aaload(ciBytecodeStream* str) { 553 pop_int(); 554 ciObjArrayKlass* array_klass = pop_objArray(); 555 if (array_klass == NULL) { 556 // Did aaload on a null reference; push a null and ignore the exception. 557 // This instruction will never continue normally. All we have to do 558 // is report a value that will meet correctly with any downstream 559 // reference types on paths that will truly be executed. This null type 560 // meets with any reference type to yield that same reference type. 561 // (The compiler will generate an unconditional exception here.) 562 push(null_type()); 563 return; 564 } 565 if (!array_klass->is_loaded()) { 566 // Only fails for some -Xcomp runs 567 trap(str, array_klass, 568 Deoptimization::make_trap_request 569 (Deoptimization::Reason_unloaded, 570 Deoptimization::Action_reinterpret)); 571 return; 572 } 573 ciKlass* element_klass = array_klass->element_klass(); 574 if (!element_klass->is_loaded() && element_klass->is_instance_klass()) { 575 Untested("unloaded array element class in ciTypeFlow"); 576 trap(str, element_klass, 577 Deoptimization::make_trap_request 578 (Deoptimization::Reason_unloaded, 579 Deoptimization::Action_reinterpret)); 580 } else { 581 push_object(element_klass); 582 } 583 } 584 585 586 // ------------------------------------------------------------------ 587 // ciTypeFlow::StateVector::do_checkcast 588 void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) { 589 bool will_link; 590 ciKlass* klass = str->get_klass(will_link); 591 if (!will_link) { 592 // VM's interpreter will not load 'klass' if object is NULL. 593 // Type flow after this block may still be needed in two situations: 594 // 1) C2 uses do_null_assert() and continues compilation for later blocks 595 // 2) C2 does an OSR compile in a later block (see bug 4778368). 596 pop_object(); 597 do_null_assert(klass); 598 } else { 599 pop_object(); 600 push_object(klass); 601 } 602 } 603 604 // ------------------------------------------------------------------ 605 // ciTypeFlow::StateVector::do_getfield 606 void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) { 607 // could add assert here for type of object. 608 pop_object(); 609 do_getstatic(str); 610 } 611 612 // ------------------------------------------------------------------ 613 // ciTypeFlow::StateVector::do_getstatic 614 void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) { 615 bool will_link; 616 ciField* field = str->get_field(will_link); 617 if (!will_link) { 618 trap(str, field->holder(), str->get_field_holder_index()); 619 } else { 620 ciType* field_type = field->type(); 621 if (!field_type->is_loaded()) { 622 // Normally, we need the field's type to be loaded if we are to 623 // do anything interesting with its value. 624 // We used to do this: trap(str, str->get_field_signature_index()); 625 // 626 // There is one good reason not to trap here. Execution can 627 // get past this "getfield" or "getstatic" if the value of 628 // the field is null. As long as the value is null, the class 629 // does not need to be loaded! The compiler must assume that 630 // the value of the unloaded class reference is null; if the code 631 // ever sees a non-null value, loading has occurred. 632 // 633 // This actually happens often enough to be annoying. If the 634 // compiler throws an uncommon trap at this bytecode, you can 635 // get an endless loop of recompilations, when all the code 636 // needs to do is load a series of null values. Also, a trap 637 // here can make an OSR entry point unreachable, triggering the 638 // assert on non_osr_block in ciTypeFlow::get_start_state. 639 // (See bug 4379915.) 640 do_null_assert(field_type->as_klass()); 641 } else { 642 push_translate(field_type); 643 } 644 } 645 } 646 647 // ------------------------------------------------------------------ 648 // ciTypeFlow::StateVector::do_invoke 649 void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str, 650 bool has_receiver) { 651 bool will_link; 652 ciSignature* declared_signature = NULL; 653 ciMethod* callee = str->get_method(will_link, &declared_signature); 654 assert(declared_signature != NULL, "cannot be null"); 655 if (!will_link) { 656 // We weren't able to find the method. 657 if (str->cur_bc() == Bytecodes::_invokedynamic) { 658 trap(str, NULL, 659 Deoptimization::make_trap_request 660 (Deoptimization::Reason_uninitialized, 661 Deoptimization::Action_reinterpret)); 662 } else { 663 ciKlass* unloaded_holder = callee->holder(); 664 trap(str, unloaded_holder, str->get_method_holder_index()); 665 } 666 } else { 667 // We are using the declared signature here because it might be 668 // different from the callee signature (Cf. invokedynamic and 669 // invokehandle). 670 ciSignatureStream sigstr(declared_signature); 671 const int arg_size = declared_signature->size(); 672 const int stack_base = stack_size() - arg_size; 673 int i = 0; 674 for( ; !sigstr.at_return_type(); sigstr.next()) { 675 ciType* type = sigstr.type(); 676 ciType* stack_type = type_at(stack(stack_base + i++)); 677 // Do I want to check this type? 678 // assert(stack_type->is_subtype_of(type), "bad type for field value"); 679 if (type->is_two_word()) { 680 ciType* stack_type2 = type_at(stack(stack_base + i++)); 681 assert(stack_type2->equals(half_type(type)), "must be 2nd half"); 682 } 683 } 684 assert(arg_size == i, "must match"); 685 for (int j = 0; j < arg_size; j++) { 686 pop(); 687 } 688 if (has_receiver) { 689 // Check this? 690 pop_object(); 691 } 692 assert(!sigstr.is_done(), "must have return type"); 693 ciType* return_type = sigstr.type(); 694 if (!return_type->is_void()) { 695 if (!return_type->is_loaded()) { 696 // As in do_getstatic(), generally speaking, we need the return type to 697 // be loaded if we are to do anything interesting with its value. 698 // We used to do this: trap(str, str->get_method_signature_index()); 699 // 700 // We do not trap here since execution can get past this invoke if 701 // the return value is null. As long as the value is null, the class 702 // does not need to be loaded! The compiler must assume that 703 // the value of the unloaded class reference is null; if the code 704 // ever sees a non-null value, loading has occurred. 705 // 706 // See do_getstatic() for similar explanation, as well as bug 4684993. 707 do_null_assert(return_type->as_klass()); 708 } else { 709 push_translate(return_type); 710 } 711 } 712 } 713 } 714 715 // ------------------------------------------------------------------ 716 // ciTypeFlow::StateVector::do_jsr 717 void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) { 718 push(ciReturnAddress::make(str->next_bci())); 719 } 720 721 // ------------------------------------------------------------------ 722 // ciTypeFlow::StateVector::do_ldc 723 void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) { 724 ciConstant con = str->get_constant(); 725 BasicType basic_type = con.basic_type(); 726 if (basic_type == T_ILLEGAL) { 727 // OutOfMemoryError in the CI while loading constant 728 push_null(); 729 outer()->record_failure("ldc did not link"); 730 return; 731 } 732 if (basic_type == T_OBJECT || basic_type == T_ARRAY) { 733 ciObject* obj = con.as_object(); 734 if (obj->is_null_object()) { 735 push_null(); 736 } else { 737 assert(obj->is_instance() || obj->is_array(), "must be java_mirror of klass"); 738 push_object(obj->klass()); 739 } 740 } else { 741 push_translate(ciType::make(basic_type)); 742 } 743 } 744 745 // ------------------------------------------------------------------ 746 // ciTypeFlow::StateVector::do_multianewarray 747 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) { 748 int dimensions = str->get_dimensions(); 749 bool will_link; 750 ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass(); 751 if (!will_link) { 752 trap(str, array_klass, str->get_klass_index()); 753 } else { 754 for (int i = 0; i < dimensions; i++) { 755 pop_int(); 756 } 757 push_object(array_klass); 758 } 759 } 760 761 // ------------------------------------------------------------------ 762 // ciTypeFlow::StateVector::do_new 763 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) { 764 bool will_link; 765 ciKlass* klass = str->get_klass(will_link); 766 if (!will_link || str->is_unresolved_klass()) { 767 trap(str, klass, str->get_klass_index()); 768 } else { 769 push_object(klass); 770 } 771 } 772 773 // ------------------------------------------------------------------ 774 // ciTypeFlow::StateVector::do_newarray 775 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) { 776 pop_int(); 777 ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index()); 778 push_object(klass); 779 } 780 781 // ------------------------------------------------------------------ 782 // ciTypeFlow::StateVector::do_putfield 783 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) { 784 do_putstatic(str); 785 if (_trap_bci != -1) return; // unloaded field holder, etc. 786 // could add assert here for type of object. 787 pop_object(); 788 } 789 790 // ------------------------------------------------------------------ 791 // ciTypeFlow::StateVector::do_putstatic 792 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) { 793 bool will_link; 794 ciField* field = str->get_field(will_link); 795 if (!will_link) { 796 trap(str, field->holder(), str->get_field_holder_index()); 797 } else { 798 ciType* field_type = field->type(); 799 ciType* type = pop_value(); 800 // Do I want to check this type? 801 // assert(type->is_subtype_of(field_type), "bad type for field value"); 802 if (field_type->is_two_word()) { 803 ciType* type2 = pop_value(); 804 assert(type2->is_two_word(), "must be 2nd half"); 805 assert(type == half_type(type2), "must be 2nd half"); 806 } 807 } 808 } 809 810 // ------------------------------------------------------------------ 811 // ciTypeFlow::StateVector::do_ret 812 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) { 813 Cell index = local(str->get_index()); 814 815 ciType* address = type_at(index); 816 assert(address->is_return_address(), "bad return address"); 817 set_type_at(index, bottom_type()); 818 } 819 820 // ------------------------------------------------------------------ 821 // ciTypeFlow::StateVector::trap 822 // 823 // Stop interpretation of this path with a trap. 824 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) { 825 _trap_bci = str->cur_bci(); 826 _trap_index = index; 827 828 // Log information about this trap: 829 CompileLog* log = outer()->env()->log(); 830 if (log != NULL) { 831 int mid = log->identify(outer()->method()); 832 int kid = (klass == NULL)? -1: log->identify(klass); 833 log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci()); 834 char buf[100]; 835 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf), 836 index)); 837 if (kid >= 0) 838 log->print(" klass='%d'", kid); 839 log->end_elem(); 840 } 841 } 842 843 // ------------------------------------------------------------------ 844 // ciTypeFlow::StateVector::do_null_assert 845 // Corresponds to graphKit::do_null_assert. 846 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) { 847 if (unloaded_klass->is_loaded()) { 848 // We failed to link, but we can still compute with this class, 849 // since it is loaded somewhere. The compiler will uncommon_trap 850 // if the object is not null, but the typeflow pass can not assume 851 // that the object will be null, otherwise it may incorrectly tell 852 // the parser that an object is known to be null. 4761344, 4807707 853 push_object(unloaded_klass); 854 } else { 855 // The class is not loaded anywhere. It is safe to model the 856 // null in the typestates, because we can compile in a null check 857 // which will deoptimize us if someone manages to load the 858 // class later. 859 push_null(); 860 } 861 } 862 863 864 // ------------------------------------------------------------------ 865 // ciTypeFlow::StateVector::apply_one_bytecode 866 // 867 // Apply the effect of one bytecode to this StateVector 868 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) { 869 _trap_bci = -1; 870 _trap_index = 0; 871 872 if (CITraceTypeFlow) { 873 tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(), 874 Bytecodes::name(str->cur_bc())); 875 } 876 877 switch(str->cur_bc()) { 878 case Bytecodes::_aaload: do_aaload(str); break; 879 880 case Bytecodes::_aastore: 881 { 882 pop_object(); 883 pop_int(); 884 pop_objArray(); 885 break; 886 } 887 case Bytecodes::_aconst_null: 888 { 889 push_null(); 890 break; 891 } 892 case Bytecodes::_aload: load_local_object(str->get_index()); break; 893 case Bytecodes::_aload_0: load_local_object(0); break; 894 case Bytecodes::_aload_1: load_local_object(1); break; 895 case Bytecodes::_aload_2: load_local_object(2); break; 896 case Bytecodes::_aload_3: load_local_object(3); break; 897 898 case Bytecodes::_anewarray: 899 { 900 pop_int(); 901 bool will_link; 902 ciKlass* element_klass = str->get_klass(will_link); 903 if (!will_link) { 904 trap(str, element_klass, str->get_klass_index()); 905 } else { 906 push_object(ciObjArrayKlass::make(element_klass)); 907 } 908 break; 909 } 910 case Bytecodes::_areturn: 911 case Bytecodes::_ifnonnull: 912 case Bytecodes::_ifnull: 913 { 914 pop_object(); 915 break; 916 } 917 case Bytecodes::_monitorenter: 918 { 919 pop_object(); 920 set_monitor_count(monitor_count() + 1); 921 break; 922 } 923 case Bytecodes::_monitorexit: 924 { 925 pop_object(); 926 assert(monitor_count() > 0, "must be a monitor to exit from"); 927 set_monitor_count(monitor_count() - 1); 928 break; 929 } 930 case Bytecodes::_arraylength: 931 { 932 pop_array(); 933 push_int(); 934 break; 935 } 936 case Bytecodes::_astore: store_local_object(str->get_index()); break; 937 case Bytecodes::_astore_0: store_local_object(0); break; 938 case Bytecodes::_astore_1: store_local_object(1); break; 939 case Bytecodes::_astore_2: store_local_object(2); break; 940 case Bytecodes::_astore_3: store_local_object(3); break; 941 942 case Bytecodes::_athrow: 943 { 944 NEEDS_CLEANUP; 945 pop_object(); 946 break; 947 } 948 case Bytecodes::_baload: 949 case Bytecodes::_caload: 950 case Bytecodes::_iaload: 951 case Bytecodes::_saload: 952 { 953 pop_int(); 954 ciTypeArrayKlass* array_klass = pop_typeArray(); 955 // Put assert here for right type? 956 push_int(); 957 break; 958 } 959 case Bytecodes::_bastore: 960 case Bytecodes::_castore: 961 case Bytecodes::_iastore: 962 case Bytecodes::_sastore: 963 { 964 pop_int(); 965 pop_int(); 966 pop_typeArray(); 967 // assert here? 968 break; 969 } 970 case Bytecodes::_bipush: 971 case Bytecodes::_iconst_m1: 972 case Bytecodes::_iconst_0: 973 case Bytecodes::_iconst_1: 974 case Bytecodes::_iconst_2: 975 case Bytecodes::_iconst_3: 976 case Bytecodes::_iconst_4: 977 case Bytecodes::_iconst_5: 978 case Bytecodes::_sipush: 979 { 980 push_int(); 981 break; 982 } 983 case Bytecodes::_checkcast: do_checkcast(str); break; 984 985 case Bytecodes::_d2f: 986 { 987 pop_double(); 988 push_float(); 989 break; 990 } 991 case Bytecodes::_d2i: 992 { 993 pop_double(); 994 push_int(); 995 break; 996 } 997 case Bytecodes::_d2l: 998 { 999 pop_double(); 1000 push_long(); 1001 break; 1002 } 1003 case Bytecodes::_dadd: 1004 case Bytecodes::_ddiv: 1005 case Bytecodes::_dmul: 1006 case Bytecodes::_drem: 1007 case Bytecodes::_dsub: 1008 { 1009 pop_double(); 1010 pop_double(); 1011 push_double(); 1012 break; 1013 } 1014 case Bytecodes::_daload: 1015 { 1016 pop_int(); 1017 ciTypeArrayKlass* array_klass = pop_typeArray(); 1018 // Put assert here for right type? 1019 push_double(); 1020 break; 1021 } 1022 case Bytecodes::_dastore: 1023 { 1024 pop_double(); 1025 pop_int(); 1026 pop_typeArray(); 1027 // assert here? 1028 break; 1029 } 1030 case Bytecodes::_dcmpg: 1031 case Bytecodes::_dcmpl: 1032 { 1033 pop_double(); 1034 pop_double(); 1035 push_int(); 1036 break; 1037 } 1038 case Bytecodes::_dconst_0: 1039 case Bytecodes::_dconst_1: 1040 { 1041 push_double(); 1042 break; 1043 } 1044 case Bytecodes::_dload: load_local_double(str->get_index()); break; 1045 case Bytecodes::_dload_0: load_local_double(0); break; 1046 case Bytecodes::_dload_1: load_local_double(1); break; 1047 case Bytecodes::_dload_2: load_local_double(2); break; 1048 case Bytecodes::_dload_3: load_local_double(3); break; 1049 1050 case Bytecodes::_dneg: 1051 { 1052 pop_double(); 1053 push_double(); 1054 break; 1055 } 1056 case Bytecodes::_dreturn: 1057 { 1058 pop_double(); 1059 break; 1060 } 1061 case Bytecodes::_dstore: store_local_double(str->get_index()); break; 1062 case Bytecodes::_dstore_0: store_local_double(0); break; 1063 case Bytecodes::_dstore_1: store_local_double(1); break; 1064 case Bytecodes::_dstore_2: store_local_double(2); break; 1065 case Bytecodes::_dstore_3: store_local_double(3); break; 1066 1067 case Bytecodes::_dup: 1068 { 1069 push(type_at_tos()); 1070 break; 1071 } 1072 case Bytecodes::_dup_x1: 1073 { 1074 ciType* value1 = pop_value(); 1075 ciType* value2 = pop_value(); 1076 push(value1); 1077 push(value2); 1078 push(value1); 1079 break; 1080 } 1081 case Bytecodes::_dup_x2: 1082 { 1083 ciType* value1 = pop_value(); 1084 ciType* value2 = pop_value(); 1085 ciType* value3 = pop_value(); 1086 push(value1); 1087 push(value3); 1088 push(value2); 1089 push(value1); 1090 break; 1091 } 1092 case Bytecodes::_dup2: 1093 { 1094 ciType* value1 = pop_value(); 1095 ciType* value2 = pop_value(); 1096 push(value2); 1097 push(value1); 1098 push(value2); 1099 push(value1); 1100 break; 1101 } 1102 case Bytecodes::_dup2_x1: 1103 { 1104 ciType* value1 = pop_value(); 1105 ciType* value2 = pop_value(); 1106 ciType* value3 = pop_value(); 1107 push(value2); 1108 push(value1); 1109 push(value3); 1110 push(value2); 1111 push(value1); 1112 break; 1113 } 1114 case Bytecodes::_dup2_x2: 1115 { 1116 ciType* value1 = pop_value(); 1117 ciType* value2 = pop_value(); 1118 ciType* value3 = pop_value(); 1119 ciType* value4 = pop_value(); 1120 push(value2); 1121 push(value1); 1122 push(value4); 1123 push(value3); 1124 push(value2); 1125 push(value1); 1126 break; 1127 } 1128 case Bytecodes::_f2d: 1129 { 1130 pop_float(); 1131 push_double(); 1132 break; 1133 } 1134 case Bytecodes::_f2i: 1135 { 1136 pop_float(); 1137 push_int(); 1138 break; 1139 } 1140 case Bytecodes::_f2l: 1141 { 1142 pop_float(); 1143 push_long(); 1144 break; 1145 } 1146 case Bytecodes::_fadd: 1147 case Bytecodes::_fdiv: 1148 case Bytecodes::_fmul: 1149 case Bytecodes::_frem: 1150 case Bytecodes::_fsub: 1151 { 1152 pop_float(); 1153 pop_float(); 1154 push_float(); 1155 break; 1156 } 1157 case Bytecodes::_faload: 1158 { 1159 pop_int(); 1160 ciTypeArrayKlass* array_klass = pop_typeArray(); 1161 // Put assert here. 1162 push_float(); 1163 break; 1164 } 1165 case Bytecodes::_fastore: 1166 { 1167 pop_float(); 1168 pop_int(); 1169 ciTypeArrayKlass* array_klass = pop_typeArray(); 1170 // Put assert here. 1171 break; 1172 } 1173 case Bytecodes::_fcmpg: 1174 case Bytecodes::_fcmpl: 1175 { 1176 pop_float(); 1177 pop_float(); 1178 push_int(); 1179 break; 1180 } 1181 case Bytecodes::_fconst_0: 1182 case Bytecodes::_fconst_1: 1183 case Bytecodes::_fconst_2: 1184 { 1185 push_float(); 1186 break; 1187 } 1188 case Bytecodes::_fload: load_local_float(str->get_index()); break; 1189 case Bytecodes::_fload_0: load_local_float(0); break; 1190 case Bytecodes::_fload_1: load_local_float(1); break; 1191 case Bytecodes::_fload_2: load_local_float(2); break; 1192 case Bytecodes::_fload_3: load_local_float(3); break; 1193 1194 case Bytecodes::_fneg: 1195 { 1196 pop_float(); 1197 push_float(); 1198 break; 1199 } 1200 case Bytecodes::_freturn: 1201 { 1202 pop_float(); 1203 break; 1204 } 1205 case Bytecodes::_fstore: store_local_float(str->get_index()); break; 1206 case Bytecodes::_fstore_0: store_local_float(0); break; 1207 case Bytecodes::_fstore_1: store_local_float(1); break; 1208 case Bytecodes::_fstore_2: store_local_float(2); break; 1209 case Bytecodes::_fstore_3: store_local_float(3); break; 1210 1211 case Bytecodes::_getfield: do_getfield(str); break; 1212 case Bytecodes::_getstatic: do_getstatic(str); break; 1213 1214 case Bytecodes::_goto: 1215 case Bytecodes::_goto_w: 1216 case Bytecodes::_nop: 1217 case Bytecodes::_return: 1218 { 1219 // do nothing. 1220 break; 1221 } 1222 case Bytecodes::_i2b: 1223 case Bytecodes::_i2c: 1224 case Bytecodes::_i2s: 1225 case Bytecodes::_ineg: 1226 { 1227 pop_int(); 1228 push_int(); 1229 break; 1230 } 1231 case Bytecodes::_i2d: 1232 { 1233 pop_int(); 1234 push_double(); 1235 break; 1236 } 1237 case Bytecodes::_i2f: 1238 { 1239 pop_int(); 1240 push_float(); 1241 break; 1242 } 1243 case Bytecodes::_i2l: 1244 { 1245 pop_int(); 1246 push_long(); 1247 break; 1248 } 1249 case Bytecodes::_iadd: 1250 case Bytecodes::_iand: 1251 case Bytecodes::_idiv: 1252 case Bytecodes::_imul: 1253 case Bytecodes::_ior: 1254 case Bytecodes::_irem: 1255 case Bytecodes::_ishl: 1256 case Bytecodes::_ishr: 1257 case Bytecodes::_isub: 1258 case Bytecodes::_iushr: 1259 case Bytecodes::_ixor: 1260 { 1261 pop_int(); 1262 pop_int(); 1263 push_int(); 1264 break; 1265 } 1266 case Bytecodes::_if_acmpeq: 1267 case Bytecodes::_if_acmpne: 1268 { 1269 pop_object(); 1270 pop_object(); 1271 break; 1272 } 1273 case Bytecodes::_if_icmpeq: 1274 case Bytecodes::_if_icmpge: 1275 case Bytecodes::_if_icmpgt: 1276 case Bytecodes::_if_icmple: 1277 case Bytecodes::_if_icmplt: 1278 case Bytecodes::_if_icmpne: 1279 { 1280 pop_int(); 1281 pop_int(); 1282 break; 1283 } 1284 case Bytecodes::_ifeq: 1285 case Bytecodes::_ifle: 1286 case Bytecodes::_iflt: 1287 case Bytecodes::_ifge: 1288 case Bytecodes::_ifgt: 1289 case Bytecodes::_ifne: 1290 case Bytecodes::_ireturn: 1291 case Bytecodes::_lookupswitch: 1292 case Bytecodes::_tableswitch: 1293 { 1294 pop_int(); 1295 break; 1296 } 1297 case Bytecodes::_iinc: 1298 { 1299 int lnum = str->get_index(); 1300 check_int(local(lnum)); 1301 store_to_local(lnum); 1302 break; 1303 } 1304 case Bytecodes::_iload: load_local_int(str->get_index()); break; 1305 case Bytecodes::_iload_0: load_local_int(0); break; 1306 case Bytecodes::_iload_1: load_local_int(1); break; 1307 case Bytecodes::_iload_2: load_local_int(2); break; 1308 case Bytecodes::_iload_3: load_local_int(3); break; 1309 1310 case Bytecodes::_instanceof: 1311 { 1312 // Check for uncommon trap: 1313 do_checkcast(str); 1314 pop_object(); 1315 push_int(); 1316 break; 1317 } 1318 case Bytecodes::_invokeinterface: do_invoke(str, true); break; 1319 case Bytecodes::_invokespecial: do_invoke(str, true); break; 1320 case Bytecodes::_invokestatic: do_invoke(str, false); break; 1321 case Bytecodes::_invokevirtual: do_invoke(str, true); break; 1322 case Bytecodes::_invokedynamic: do_invoke(str, false); break; 1323 1324 case Bytecodes::_istore: store_local_int(str->get_index()); break; 1325 case Bytecodes::_istore_0: store_local_int(0); break; 1326 case Bytecodes::_istore_1: store_local_int(1); break; 1327 case Bytecodes::_istore_2: store_local_int(2); break; 1328 case Bytecodes::_istore_3: store_local_int(3); break; 1329 1330 case Bytecodes::_jsr: 1331 case Bytecodes::_jsr_w: do_jsr(str); break; 1332 1333 case Bytecodes::_l2d: 1334 { 1335 pop_long(); 1336 push_double(); 1337 break; 1338 } 1339 case Bytecodes::_l2f: 1340 { 1341 pop_long(); 1342 push_float(); 1343 break; 1344 } 1345 case Bytecodes::_l2i: 1346 { 1347 pop_long(); 1348 push_int(); 1349 break; 1350 } 1351 case Bytecodes::_ladd: 1352 case Bytecodes::_land: 1353 case Bytecodes::_ldiv: 1354 case Bytecodes::_lmul: 1355 case Bytecodes::_lor: 1356 case Bytecodes::_lrem: 1357 case Bytecodes::_lsub: 1358 case Bytecodes::_lxor: 1359 { 1360 pop_long(); 1361 pop_long(); 1362 push_long(); 1363 break; 1364 } 1365 case Bytecodes::_laload: 1366 { 1367 pop_int(); 1368 ciTypeArrayKlass* array_klass = pop_typeArray(); 1369 // Put assert here for right type? 1370 push_long(); 1371 break; 1372 } 1373 case Bytecodes::_lastore: 1374 { 1375 pop_long(); 1376 pop_int(); 1377 pop_typeArray(); 1378 // assert here? 1379 break; 1380 } 1381 case Bytecodes::_lcmp: 1382 { 1383 pop_long(); 1384 pop_long(); 1385 push_int(); 1386 break; 1387 } 1388 case Bytecodes::_lconst_0: 1389 case Bytecodes::_lconst_1: 1390 { 1391 push_long(); 1392 break; 1393 } 1394 case Bytecodes::_ldc: 1395 case Bytecodes::_ldc_w: 1396 case Bytecodes::_ldc2_w: 1397 { 1398 do_ldc(str); 1399 break; 1400 } 1401 1402 case Bytecodes::_lload: load_local_long(str->get_index()); break; 1403 case Bytecodes::_lload_0: load_local_long(0); break; 1404 case Bytecodes::_lload_1: load_local_long(1); break; 1405 case Bytecodes::_lload_2: load_local_long(2); break; 1406 case Bytecodes::_lload_3: load_local_long(3); break; 1407 1408 case Bytecodes::_lneg: 1409 { 1410 pop_long(); 1411 push_long(); 1412 break; 1413 } 1414 case Bytecodes::_lreturn: 1415 { 1416 pop_long(); 1417 break; 1418 } 1419 case Bytecodes::_lshl: 1420 case Bytecodes::_lshr: 1421 case Bytecodes::_lushr: 1422 { 1423 pop_int(); 1424 pop_long(); 1425 push_long(); 1426 break; 1427 } 1428 case Bytecodes::_lstore: store_local_long(str->get_index()); break; 1429 case Bytecodes::_lstore_0: store_local_long(0); break; 1430 case Bytecodes::_lstore_1: store_local_long(1); break; 1431 case Bytecodes::_lstore_2: store_local_long(2); break; 1432 case Bytecodes::_lstore_3: store_local_long(3); break; 1433 1434 case Bytecodes::_multianewarray: do_multianewarray(str); break; 1435 1436 case Bytecodes::_new: do_new(str); break; 1437 1438 case Bytecodes::_newarray: do_newarray(str); break; 1439 1440 case Bytecodes::_pop: 1441 { 1442 pop(); 1443 break; 1444 } 1445 case Bytecodes::_pop2: 1446 { 1447 pop(); 1448 pop(); 1449 break; 1450 } 1451 1452 case Bytecodes::_putfield: do_putfield(str); break; 1453 case Bytecodes::_putstatic: do_putstatic(str); break; 1454 1455 case Bytecodes::_ret: do_ret(str); break; 1456 1457 case Bytecodes::_swap: 1458 { 1459 ciType* value1 = pop_value(); 1460 ciType* value2 = pop_value(); 1461 push(value1); 1462 push(value2); 1463 break; 1464 } 1465 case Bytecodes::_wide: 1466 default: 1467 { 1468 // The iterator should skip this. 1469 ShouldNotReachHere(); 1470 break; 1471 } 1472 } 1473 1474 if (CITraceTypeFlow) { 1475 print_on(tty); 1476 } 1477 1478 return (_trap_bci != -1); 1479 } 1480 1481 #ifndef PRODUCT 1482 // ------------------------------------------------------------------ 1483 // ciTypeFlow::StateVector::print_cell_on 1484 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const { 1485 ciType* type = type_at(c); 1486 if (type == top_type()) { 1487 st->print("top"); 1488 } else if (type == bottom_type()) { 1489 st->print("bottom"); 1490 } else if (type == null_type()) { 1491 st->print("null"); 1492 } else if (type == long2_type()) { 1493 st->print("long2"); 1494 } else if (type == double2_type()) { 1495 st->print("double2"); 1496 } else if (is_int(type)) { 1497 st->print("int"); 1498 } else if (is_long(type)) { 1499 st->print("long"); 1500 } else if (is_float(type)) { 1501 st->print("float"); 1502 } else if (is_double(type)) { 1503 st->print("double"); 1504 } else if (type->is_return_address()) { 1505 st->print("address(%d)", type->as_return_address()->bci()); 1506 } else { 1507 if (type->is_klass()) { 1508 type->as_klass()->name()->print_symbol_on(st); 1509 } else { 1510 st->print("UNEXPECTED TYPE"); 1511 type->print(); 1512 } 1513 } 1514 } 1515 1516 // ------------------------------------------------------------------ 1517 // ciTypeFlow::StateVector::print_on 1518 void ciTypeFlow::StateVector::print_on(outputStream* st) const { 1519 int num_locals = _outer->max_locals(); 1520 int num_stack = stack_size(); 1521 int num_monitors = monitor_count(); 1522 st->print_cr(" State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors); 1523 if (num_stack >= 0) { 1524 int i; 1525 for (i = 0; i < num_locals; i++) { 1526 st->print(" local %2d : ", i); 1527 print_cell_on(st, local(i)); 1528 st->cr(); 1529 } 1530 for (i = 0; i < num_stack; i++) { 1531 st->print(" stack %2d : ", i); 1532 print_cell_on(st, stack(i)); 1533 st->cr(); 1534 } 1535 } 1536 } 1537 #endif 1538 1539 1540 // ------------------------------------------------------------------ 1541 // ciTypeFlow::SuccIter::next 1542 // 1543 void ciTypeFlow::SuccIter::next() { 1544 int succ_ct = _pred->successors()->length(); 1545 int next = _index + 1; 1546 if (next < succ_ct) { 1547 _index = next; 1548 _succ = _pred->successors()->at(next); 1549 return; 1550 } 1551 for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) { 1552 // Do not compile any code for unloaded exception types. 1553 // Following compiler passes are responsible for doing this also. 1554 ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i); 1555 if (exception_klass->is_loaded()) { 1556 _index = next; 1557 _succ = _pred->exceptions()->at(i); 1558 return; 1559 } 1560 next++; 1561 } 1562 _index = -1; 1563 _succ = NULL; 1564 } 1565 1566 // ------------------------------------------------------------------ 1567 // ciTypeFlow::SuccIter::set_succ 1568 // 1569 void ciTypeFlow::SuccIter::set_succ(Block* succ) { 1570 int succ_ct = _pred->successors()->length(); 1571 if (_index < succ_ct) { 1572 _pred->successors()->at_put(_index, succ); 1573 } else { 1574 int idx = _index - succ_ct; 1575 _pred->exceptions()->at_put(idx, succ); 1576 } 1577 } 1578 1579 // ciTypeFlow::Block 1580 // 1581 // A basic block. 1582 1583 // ------------------------------------------------------------------ 1584 // ciTypeFlow::Block::Block 1585 ciTypeFlow::Block::Block(ciTypeFlow* outer, 1586 ciBlock *ciblk, 1587 ciTypeFlow::JsrSet* jsrs) { 1588 _ciblock = ciblk; 1589 _exceptions = NULL; 1590 _exc_klasses = NULL; 1591 _successors = NULL; 1592 _predecessors = new (outer->arena()) GrowableArray<Block*>(outer->arena(), 1, 0, NULL); 1593 _state = new (outer->arena()) StateVector(outer); 1594 JsrSet* new_jsrs = 1595 new (outer->arena()) JsrSet(outer->arena(), jsrs->size()); 1596 jsrs->copy_into(new_jsrs); 1597 _jsrs = new_jsrs; 1598 _next = NULL; 1599 _on_work_list = false; 1600 _backedge_copy = false; 1601 _has_monitorenter = false; 1602 _trap_bci = -1; 1603 _trap_index = 0; 1604 df_init(); 1605 1606 if (CITraceTypeFlow) { 1607 tty->print_cr(">> Created new block"); 1608 print_on(tty); 1609 } 1610 1611 assert(this->outer() == outer, "outer link set up"); 1612 assert(!outer->have_block_count(), "must not have mapped blocks yet"); 1613 } 1614 1615 // ------------------------------------------------------------------ 1616 // ciTypeFlow::Block::df_init 1617 void ciTypeFlow::Block::df_init() { 1618 _pre_order = -1; assert(!has_pre_order(), ""); 1619 _post_order = -1; assert(!has_post_order(), ""); 1620 _loop = NULL; 1621 _irreducible_entry = false; 1622 _rpo_next = NULL; 1623 } 1624 1625 // ------------------------------------------------------------------ 1626 // ciTypeFlow::Block::successors 1627 // 1628 // Get the successors for this Block. 1629 GrowableArray<ciTypeFlow::Block*>* 1630 ciTypeFlow::Block::successors(ciBytecodeStream* str, 1631 ciTypeFlow::StateVector* state, 1632 ciTypeFlow::JsrSet* jsrs) { 1633 if (_successors == NULL) { 1634 if (CITraceTypeFlow) { 1635 tty->print(">> Computing successors for block "); 1636 print_value_on(tty); 1637 tty->cr(); 1638 } 1639 1640 ciTypeFlow* analyzer = outer(); 1641 Arena* arena = analyzer->arena(); 1642 Block* block = NULL; 1643 bool has_successor = !has_trap() && 1644 (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size()); 1645 if (!has_successor) { 1646 _successors = 1647 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1648 // No successors 1649 } else if (control() == ciBlock::fall_through_bci) { 1650 assert(str->cur_bci() == limit(), "bad block end"); 1651 // This block simply falls through to the next. 1652 _successors = 1653 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1654 1655 Block* block = analyzer->block_at(limit(), _jsrs); 1656 assert(_successors->length() == FALL_THROUGH, ""); 1657 _successors->append(block); 1658 } else { 1659 int current_bci = str->cur_bci(); 1660 int next_bci = str->next_bci(); 1661 int branch_bci = -1; 1662 Block* target = NULL; 1663 assert(str->next_bci() == limit(), "bad block end"); 1664 // This block is not a simple fall-though. Interpret 1665 // the current bytecode to find our successors. 1666 switch (str->cur_bc()) { 1667 case Bytecodes::_ifeq: case Bytecodes::_ifne: 1668 case Bytecodes::_iflt: case Bytecodes::_ifge: 1669 case Bytecodes::_ifgt: case Bytecodes::_ifle: 1670 case Bytecodes::_if_icmpeq: case Bytecodes::_if_icmpne: 1671 case Bytecodes::_if_icmplt: case Bytecodes::_if_icmpge: 1672 case Bytecodes::_if_icmpgt: case Bytecodes::_if_icmple: 1673 case Bytecodes::_if_acmpeq: case Bytecodes::_if_acmpne: 1674 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: 1675 // Our successors are the branch target and the next bci. 1676 branch_bci = str->get_dest(); 1677 _successors = 1678 new (arena) GrowableArray<Block*>(arena, 2, 0, NULL); 1679 assert(_successors->length() == IF_NOT_TAKEN, ""); 1680 _successors->append(analyzer->block_at(next_bci, jsrs)); 1681 assert(_successors->length() == IF_TAKEN, ""); 1682 _successors->append(analyzer->block_at(branch_bci, jsrs)); 1683 break; 1684 1685 case Bytecodes::_goto: 1686 branch_bci = str->get_dest(); 1687 _successors = 1688 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1689 assert(_successors->length() == GOTO_TARGET, ""); 1690 _successors->append(analyzer->block_at(branch_bci, jsrs)); 1691 break; 1692 1693 case Bytecodes::_jsr: 1694 branch_bci = str->get_dest(); 1695 _successors = 1696 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1697 assert(_successors->length() == GOTO_TARGET, ""); 1698 _successors->append(analyzer->block_at(branch_bci, jsrs)); 1699 break; 1700 1701 case Bytecodes::_goto_w: 1702 case Bytecodes::_jsr_w: 1703 _successors = 1704 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1705 assert(_successors->length() == GOTO_TARGET, ""); 1706 _successors->append(analyzer->block_at(str->get_far_dest(), jsrs)); 1707 break; 1708 1709 case Bytecodes::_tableswitch: { 1710 Bytecode_tableswitch tableswitch(str); 1711 1712 int len = tableswitch.length(); 1713 _successors = 1714 new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL); 1715 int bci = current_bci + tableswitch.default_offset(); 1716 Block* block = analyzer->block_at(bci, jsrs); 1717 assert(_successors->length() == SWITCH_DEFAULT, ""); 1718 _successors->append(block); 1719 while (--len >= 0) { 1720 int bci = current_bci + tableswitch.dest_offset_at(len); 1721 block = analyzer->block_at(bci, jsrs); 1722 assert(_successors->length() >= SWITCH_CASES, ""); 1723 _successors->append_if_missing(block); 1724 } 1725 break; 1726 } 1727 1728 case Bytecodes::_lookupswitch: { 1729 Bytecode_lookupswitch lookupswitch(str); 1730 1731 int npairs = lookupswitch.number_of_pairs(); 1732 _successors = 1733 new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL); 1734 int bci = current_bci + lookupswitch.default_offset(); 1735 Block* block = analyzer->block_at(bci, jsrs); 1736 assert(_successors->length() == SWITCH_DEFAULT, ""); 1737 _successors->append(block); 1738 while(--npairs >= 0) { 1739 LookupswitchPair pair = lookupswitch.pair_at(npairs); 1740 int bci = current_bci + pair.offset(); 1741 Block* block = analyzer->block_at(bci, jsrs); 1742 assert(_successors->length() >= SWITCH_CASES, ""); 1743 _successors->append_if_missing(block); 1744 } 1745 break; 1746 } 1747 1748 case Bytecodes::_athrow: case Bytecodes::_ireturn: 1749 case Bytecodes::_lreturn: case Bytecodes::_freturn: 1750 case Bytecodes::_dreturn: case Bytecodes::_areturn: 1751 case Bytecodes::_return: 1752 _successors = 1753 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1754 // No successors 1755 break; 1756 1757 case Bytecodes::_ret: { 1758 _successors = 1759 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL); 1760 1761 Cell local = state->local(str->get_index()); 1762 ciType* return_address = state->type_at(local); 1763 assert(return_address->is_return_address(), "verify: wrong type"); 1764 int bci = return_address->as_return_address()->bci(); 1765 assert(_successors->length() == GOTO_TARGET, ""); 1766 _successors->append(analyzer->block_at(bci, jsrs)); 1767 break; 1768 } 1769 1770 case Bytecodes::_wide: 1771 default: 1772 ShouldNotReachHere(); 1773 break; 1774 } 1775 } 1776 1777 // Set predecessor information 1778 for (int i = 0; i < _successors->length(); i++) { 1779 Block* block = _successors->at(i); 1780 block->predecessors()->append(this); 1781 } 1782 } 1783 return _successors; 1784 } 1785 1786 // ------------------------------------------------------------------ 1787 // ciTypeFlow::Block:compute_exceptions 1788 // 1789 // Compute the exceptional successors and types for this Block. 1790 void ciTypeFlow::Block::compute_exceptions() { 1791 assert(_exceptions == NULL && _exc_klasses == NULL, "repeat"); 1792 1793 if (CITraceTypeFlow) { 1794 tty->print(">> Computing exceptions for block "); 1795 print_value_on(tty); 1796 tty->cr(); 1797 } 1798 1799 ciTypeFlow* analyzer = outer(); 1800 Arena* arena = analyzer->arena(); 1801 1802 // Any bci in the block will do. 1803 ciExceptionHandlerStream str(analyzer->method(), start()); 1804 1805 // Allocate our growable arrays. 1806 int exc_count = str.count(); 1807 _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL); 1808 _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count, 1809 0, NULL); 1810 1811 for ( ; !str.is_done(); str.next()) { 1812 ciExceptionHandler* handler = str.handler(); 1813 int bci = handler->handler_bci(); 1814 ciInstanceKlass* klass = NULL; 1815 if (bci == -1) { 1816 // There is no catch all. It is possible to exit the method. 1817 break; 1818 } 1819 if (handler->is_catch_all()) { 1820 klass = analyzer->env()->Throwable_klass(); 1821 } else { 1822 klass = handler->catch_klass(); 1823 } 1824 Block* block = analyzer->block_at(bci, _jsrs); 1825 _exceptions->append(block); 1826 block->predecessors()->append(this); 1827 _exc_klasses->append(klass); 1828 } 1829 } 1830 1831 // ------------------------------------------------------------------ 1832 // ciTypeFlow::Block::set_backedge_copy 1833 // Use this only to make a pre-existing public block into a backedge copy. 1834 void ciTypeFlow::Block::set_backedge_copy(bool z) { 1835 assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public"); 1836 _backedge_copy = z; 1837 } 1838 1839 // ------------------------------------------------------------------ 1840 // ciTypeFlow::Block::is_clonable_exit 1841 // 1842 // At most 2 normal successors, one of which continues looping, 1843 // and all exceptional successors must exit. 1844 bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) { 1845 int normal_cnt = 0; 1846 int in_loop_cnt = 0; 1847 for (SuccIter iter(this); !iter.done(); iter.next()) { 1848 Block* succ = iter.succ(); 1849 if (iter.is_normal_ctrl()) { 1850 if (++normal_cnt > 2) return false; 1851 if (lp->contains(succ->loop())) { 1852 if (++in_loop_cnt > 1) return false; 1853 } 1854 } else { 1855 if (lp->contains(succ->loop())) return false; 1856 } 1857 } 1858 return in_loop_cnt == 1; 1859 } 1860 1861 // ------------------------------------------------------------------ 1862 // ciTypeFlow::Block::looping_succ 1863 // 1864 ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) { 1865 assert(successors()->length() <= 2, "at most 2 normal successors"); 1866 for (SuccIter iter(this); !iter.done(); iter.next()) { 1867 Block* succ = iter.succ(); 1868 if (lp->contains(succ->loop())) { 1869 return succ; 1870 } 1871 } 1872 return NULL; 1873 } 1874 1875 #ifndef PRODUCT 1876 // ------------------------------------------------------------------ 1877 // ciTypeFlow::Block::print_value_on 1878 void ciTypeFlow::Block::print_value_on(outputStream* st) const { 1879 if (has_pre_order()) st->print("#%-2d ", pre_order()); 1880 if (has_rpo()) st->print("rpo#%-2d ", rpo()); 1881 st->print("[%d - %d)", start(), limit()); 1882 if (is_loop_head()) st->print(" lphd"); 1883 if (is_irreducible_entry()) st->print(" irred"); 1884 if (_jsrs->size() > 0) { st->print("/"); _jsrs->print_on(st); } 1885 if (is_backedge_copy()) st->print("/backedge_copy"); 1886 } 1887 1888 // ------------------------------------------------------------------ 1889 // ciTypeFlow::Block::print_on 1890 void ciTypeFlow::Block::print_on(outputStream* st) const { 1891 if ((Verbose || WizardMode) && (limit() >= 0)) { 1892 // Don't print 'dummy' blocks (i.e. blocks with limit() '-1') 1893 outer()->method()->print_codes_on(start(), limit(), st); 1894 } 1895 st->print_cr(" ==================================================== "); 1896 st->print (" "); 1897 print_value_on(st); 1898 st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr(); 1899 if (loop() && loop()->parent() != NULL) { 1900 st->print(" loops:"); 1901 Loop* lp = loop(); 1902 do { 1903 st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order()); 1904 if (lp->is_irreducible()) st->print("(ir)"); 1905 lp = lp->parent(); 1906 } while (lp->parent() != NULL); 1907 } 1908 st->cr(); 1909 _state->print_on(st); 1910 if (_successors == NULL) { 1911 st->print_cr(" No successor information"); 1912 } else { 1913 int num_successors = _successors->length(); 1914 st->print_cr(" Successors : %d", num_successors); 1915 for (int i = 0; i < num_successors; i++) { 1916 Block* successor = _successors->at(i); 1917 st->print(" "); 1918 successor->print_value_on(st); 1919 st->cr(); 1920 } 1921 } 1922 if (_predecessors == NULL) { 1923 st->print_cr(" No predecessor information"); 1924 } else { 1925 int num_predecessors = _predecessors->length(); 1926 st->print_cr(" Predecessors : %d", num_predecessors); 1927 for (int i = 0; i < num_predecessors; i++) { 1928 Block* predecessor = _predecessors->at(i); 1929 st->print(" "); 1930 predecessor->print_value_on(st); 1931 st->cr(); 1932 } 1933 } 1934 if (_exceptions == NULL) { 1935 st->print_cr(" No exception information"); 1936 } else { 1937 int num_exceptions = _exceptions->length(); 1938 st->print_cr(" Exceptions : %d", num_exceptions); 1939 for (int i = 0; i < num_exceptions; i++) { 1940 Block* exc_succ = _exceptions->at(i); 1941 ciInstanceKlass* exc_klass = _exc_klasses->at(i); 1942 st->print(" "); 1943 exc_succ->print_value_on(st); 1944 st->print(" -- "); 1945 exc_klass->name()->print_symbol_on(st); 1946 st->cr(); 1947 } 1948 } 1949 if (has_trap()) { 1950 st->print_cr(" Traps on %d with trap index %d", trap_bci(), trap_index()); 1951 } 1952 st->print_cr(" ==================================================== "); 1953 } 1954 #endif 1955 1956 #ifndef PRODUCT 1957 // ------------------------------------------------------------------ 1958 // ciTypeFlow::LocalSet::print_on 1959 void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const { 1960 st->print("{"); 1961 for (int i = 0; i < max; i++) { 1962 if (test(i)) st->print(" %d", i); 1963 } 1964 if (limit > max) { 1965 st->print(" %d..%d ", max, limit); 1966 } 1967 st->print(" }"); 1968 } 1969 #endif 1970 1971 // ciTypeFlow 1972 // 1973 // This is a pass over the bytecodes which computes the following: 1974 // basic block structure 1975 // interpreter type-states (a la the verifier) 1976 1977 // ------------------------------------------------------------------ 1978 // ciTypeFlow::ciTypeFlow 1979 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) { 1980 _env = env; 1981 _method = method; 1982 _methodBlocks = method->get_method_blocks(); 1983 _max_locals = method->max_locals(); 1984 _max_stack = method->max_stack(); 1985 _code_size = method->code_size(); 1986 _has_irreducible_entry = false; 1987 _osr_bci = osr_bci; 1988 _failure_reason = NULL; 1989 assert(0 <= start_bci() && start_bci() < code_size() , "correct osr_bci argument: 0 <= %d < %d", start_bci(), code_size()); 1990 _work_list = NULL; 1991 1992 _ciblock_count = _methodBlocks->num_blocks(); 1993 _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count); 1994 for (int i = 0; i < _ciblock_count; i++) { 1995 _idx_to_blocklist[i] = NULL; 1996 } 1997 _block_map = NULL; // until all blocks are seen 1998 _jsr_count = 0; 1999 _jsr_records = NULL; 2000 } 2001 2002 // ------------------------------------------------------------------ 2003 // ciTypeFlow::work_list_next 2004 // 2005 // Get the next basic block from our work list. 2006 ciTypeFlow::Block* ciTypeFlow::work_list_next() { 2007 assert(!work_list_empty(), "work list must not be empty"); 2008 Block* next_block = _work_list; 2009 _work_list = next_block->next(); 2010 next_block->set_next(NULL); 2011 next_block->set_on_work_list(false); 2012 return next_block; 2013 } 2014 2015 // ------------------------------------------------------------------ 2016 // ciTypeFlow::add_to_work_list 2017 // 2018 // Add a basic block to our work list. 2019 // List is sorted by decreasing postorder sort (same as increasing RPO) 2020 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) { 2021 assert(!block->is_on_work_list(), "must not already be on work list"); 2022 2023 if (CITraceTypeFlow) { 2024 tty->print(">> Adding block "); 2025 block->print_value_on(tty); 2026 tty->print_cr(" to the work list : "); 2027 } 2028 2029 block->set_on_work_list(true); 2030 2031 // decreasing post order sort 2032 2033 Block* prev = NULL; 2034 Block* current = _work_list; 2035 int po = block->post_order(); 2036 while (current != NULL) { 2037 if (!current->has_post_order() || po > current->post_order()) 2038 break; 2039 prev = current; 2040 current = current->next(); 2041 } 2042 if (prev == NULL) { 2043 block->set_next(_work_list); 2044 _work_list = block; 2045 } else { 2046 block->set_next(current); 2047 prev->set_next(block); 2048 } 2049 2050 if (CITraceTypeFlow) { 2051 tty->cr(); 2052 } 2053 } 2054 2055 // ------------------------------------------------------------------ 2056 // ciTypeFlow::block_at 2057 // 2058 // Return the block beginning at bci which has a JsrSet compatible 2059 // with jsrs. 2060 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) { 2061 // First find the right ciBlock. 2062 if (CITraceTypeFlow) { 2063 tty->print(">> Requesting block for %d/", bci); 2064 jsrs->print_on(tty); 2065 tty->cr(); 2066 } 2067 2068 ciBlock* ciblk = _methodBlocks->block_containing(bci); 2069 assert(ciblk->start_bci() == bci, "bad ciBlock boundaries"); 2070 Block* block = get_block_for(ciblk->index(), jsrs, option); 2071 2072 assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result"); 2073 2074 if (CITraceTypeFlow) { 2075 if (block != NULL) { 2076 tty->print(">> Found block "); 2077 block->print_value_on(tty); 2078 tty->cr(); 2079 } else { 2080 tty->print_cr(">> No such block."); 2081 } 2082 } 2083 2084 return block; 2085 } 2086 2087 // ------------------------------------------------------------------ 2088 // ciTypeFlow::make_jsr_record 2089 // 2090 // Make a JsrRecord for a given (entry, return) pair, if such a record 2091 // does not already exist. 2092 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address, 2093 int return_address) { 2094 if (_jsr_records == NULL) { 2095 _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(), 2096 _jsr_count, 2097 0, 2098 NULL); 2099 } 2100 JsrRecord* record = NULL; 2101 int len = _jsr_records->length(); 2102 for (int i = 0; i < len; i++) { 2103 JsrRecord* record = _jsr_records->at(i); 2104 if (record->entry_address() == entry_address && 2105 record->return_address() == return_address) { 2106 return record; 2107 } 2108 } 2109 2110 record = new (arena()) JsrRecord(entry_address, return_address); 2111 _jsr_records->append(record); 2112 return record; 2113 } 2114 2115 // ------------------------------------------------------------------ 2116 // ciTypeFlow::flow_exceptions 2117 // 2118 // Merge the current state into all exceptional successors at the 2119 // current point in the code. 2120 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions, 2121 GrowableArray<ciInstanceKlass*>* exc_klasses, 2122 ciTypeFlow::StateVector* state) { 2123 int len = exceptions->length(); 2124 assert(exc_klasses->length() == len, "must have same length"); 2125 for (int i = 0; i < len; i++) { 2126 Block* block = exceptions->at(i); 2127 ciInstanceKlass* exception_klass = exc_klasses->at(i); 2128 2129 if (!exception_klass->is_loaded()) { 2130 // Do not compile any code for unloaded exception types. 2131 // Following compiler passes are responsible for doing this also. 2132 continue; 2133 } 2134 2135 if (block->meet_exception(exception_klass, state)) { 2136 // Block was modified and has PO. Add it to the work list. 2137 if (block->has_post_order() && 2138 !block->is_on_work_list()) { 2139 add_to_work_list(block); 2140 } 2141 } 2142 } 2143 } 2144 2145 // ------------------------------------------------------------------ 2146 // ciTypeFlow::flow_successors 2147 // 2148 // Merge the current state into all successors at the current point 2149 // in the code. 2150 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors, 2151 ciTypeFlow::StateVector* state) { 2152 int len = successors->length(); 2153 for (int i = 0; i < len; i++) { 2154 Block* block = successors->at(i); 2155 if (block->meet(state)) { 2156 // Block was modified and has PO. Add it to the work list. 2157 if (block->has_post_order() && 2158 !block->is_on_work_list()) { 2159 add_to_work_list(block); 2160 } 2161 } 2162 } 2163 } 2164 2165 // ------------------------------------------------------------------ 2166 // ciTypeFlow::can_trap 2167 // 2168 // Tells if a given instruction is able to generate an exception edge. 2169 bool ciTypeFlow::can_trap(ciBytecodeStream& str) { 2170 // Cf. GenerateOopMap::do_exception_edge. 2171 if (!Bytecodes::can_trap(str.cur_bc())) return false; 2172 2173 switch (str.cur_bc()) { 2174 // %%% FIXME: ldc of Class can generate an exception 2175 case Bytecodes::_ldc: 2176 case Bytecodes::_ldc_w: 2177 case Bytecodes::_ldc2_w: 2178 case Bytecodes::_aload_0: 2179 // These bytecodes can trap for rewriting. We need to assume that 2180 // they do not throw exceptions to make the monitor analysis work. 2181 return false; 2182 2183 case Bytecodes::_ireturn: 2184 case Bytecodes::_lreturn: 2185 case Bytecodes::_freturn: 2186 case Bytecodes::_dreturn: 2187 case Bytecodes::_areturn: 2188 case Bytecodes::_return: 2189 // We can assume the monitor stack is empty in this analysis. 2190 return false; 2191 2192 case Bytecodes::_monitorexit: 2193 // We can assume monitors are matched in this analysis. 2194 return false; 2195 2196 default: 2197 return true; 2198 } 2199 } 2200 2201 // ------------------------------------------------------------------ 2202 // ciTypeFlow::clone_loop_heads 2203 // 2204 // Clone the loop heads 2205 bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) { 2206 bool rslt = false; 2207 for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) { 2208 lp = iter.current(); 2209 Block* head = lp->head(); 2210 if (lp == loop_tree_root() || 2211 lp->is_irreducible() || 2212 !head->is_clonable_exit(lp)) 2213 continue; 2214 2215 // Avoid BoxLock merge. 2216 if (EliminateNestedLocks && head->has_monitorenter()) 2217 continue; 2218 2219 // check not already cloned 2220 if (head->backedge_copy_count() != 0) 2221 continue; 2222 2223 // Don't clone head of OSR loop to get correct types in start block. 2224 if (is_osr_flow() && head->start() == start_bci()) 2225 continue; 2226 2227 // check _no_ shared head below us 2228 Loop* ch; 2229 for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling()); 2230 if (ch != NULL) 2231 continue; 2232 2233 // Clone head 2234 Block* new_head = head->looping_succ(lp); 2235 Block* clone = clone_loop_head(lp, temp_vector, temp_set); 2236 // Update lp's info 2237 clone->set_loop(lp); 2238 lp->set_head(new_head); 2239 lp->set_tail(clone); 2240 // And move original head into outer loop 2241 head->set_loop(lp->parent()); 2242 2243 rslt = true; 2244 } 2245 return rslt; 2246 } 2247 2248 // ------------------------------------------------------------------ 2249 // ciTypeFlow::clone_loop_head 2250 // 2251 // Clone lp's head and replace tail's successors with clone. 2252 // 2253 // | 2254 // v 2255 // head <-> body 2256 // | 2257 // v 2258 // exit 2259 // 2260 // new_head 2261 // 2262 // | 2263 // v 2264 // head ----------\ 2265 // | | 2266 // | v 2267 // | clone <-> body 2268 // | | 2269 // | /--/ 2270 // | | 2271 // v v 2272 // exit 2273 // 2274 ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) { 2275 Block* head = lp->head(); 2276 Block* tail = lp->tail(); 2277 if (CITraceTypeFlow) { 2278 tty->print(">> Requesting clone of loop head "); head->print_value_on(tty); 2279 tty->print(" for predecessor "); tail->print_value_on(tty); 2280 tty->cr(); 2281 } 2282 Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy); 2283 assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges"); 2284 2285 assert(!clone->has_pre_order(), "just created"); 2286 clone->set_next_pre_order(); 2287 2288 // Insert clone after (orig) tail in reverse post order 2289 clone->set_rpo_next(tail->rpo_next()); 2290 tail->set_rpo_next(clone); 2291 2292 // tail->head becomes tail->clone 2293 for (SuccIter iter(tail); !iter.done(); iter.next()) { 2294 if (iter.succ() == head) { 2295 iter.set_succ(clone); 2296 // Update predecessor information 2297 head->predecessors()->remove(tail); 2298 clone->predecessors()->append(tail); 2299 } 2300 } 2301 flow_block(tail, temp_vector, temp_set); 2302 if (head == tail) { 2303 // For self-loops, clone->head becomes clone->clone 2304 flow_block(clone, temp_vector, temp_set); 2305 for (SuccIter iter(clone); !iter.done(); iter.next()) { 2306 if (iter.succ() == head) { 2307 iter.set_succ(clone); 2308 // Update predecessor information 2309 head->predecessors()->remove(clone); 2310 clone->predecessors()->append(clone); 2311 break; 2312 } 2313 } 2314 } 2315 flow_block(clone, temp_vector, temp_set); 2316 2317 return clone; 2318 } 2319 2320 // ------------------------------------------------------------------ 2321 // ciTypeFlow::flow_block 2322 // 2323 // Interpret the effects of the bytecodes on the incoming state 2324 // vector of a basic block. Push the changed state to succeeding 2325 // basic blocks. 2326 void ciTypeFlow::flow_block(ciTypeFlow::Block* block, 2327 ciTypeFlow::StateVector* state, 2328 ciTypeFlow::JsrSet* jsrs) { 2329 if (CITraceTypeFlow) { 2330 tty->print("\n>> ANALYZING BLOCK : "); 2331 tty->cr(); 2332 block->print_on(tty); 2333 } 2334 assert(block->has_pre_order(), "pre-order is assigned before 1st flow"); 2335 2336 int start = block->start(); 2337 int limit = block->limit(); 2338 int control = block->control(); 2339 if (control != ciBlock::fall_through_bci) { 2340 limit = control; 2341 } 2342 2343 // Grab the state from the current block. 2344 block->copy_state_into(state); 2345 state->def_locals()->clear(); 2346 2347 GrowableArray<Block*>* exceptions = block->exceptions(); 2348 GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses(); 2349 bool has_exceptions = exceptions->length() > 0; 2350 2351 bool exceptions_used = false; 2352 2353 ciBytecodeStream str(method()); 2354 str.reset_to_bci(start); 2355 Bytecodes::Code code; 2356 while ((code = str.next()) != ciBytecodeStream::EOBC() && 2357 str.cur_bci() < limit) { 2358 // Check for exceptional control flow from this point. 2359 if (has_exceptions && can_trap(str)) { 2360 flow_exceptions(exceptions, exc_klasses, state); 2361 exceptions_used = true; 2362 } 2363 // Apply the effects of the current bytecode to our state. 2364 bool res = state->apply_one_bytecode(&str); 2365 2366 // Watch for bailouts. 2367 if (failing()) return; 2368 2369 if (str.cur_bc() == Bytecodes::_monitorenter) { 2370 block->set_has_monitorenter(); 2371 } 2372 2373 if (res) { 2374 2375 // We have encountered a trap. Record it in this block. 2376 block->set_trap(state->trap_bci(), state->trap_index()); 2377 2378 if (CITraceTypeFlow) { 2379 tty->print_cr(">> Found trap"); 2380 block->print_on(tty); 2381 } 2382 2383 // Save set of locals defined in this block 2384 block->def_locals()->add(state->def_locals()); 2385 2386 // Record (no) successors. 2387 block->successors(&str, state, jsrs); 2388 2389 assert(!has_exceptions || exceptions_used, "Not removing exceptions"); 2390 2391 // Discontinue interpretation of this Block. 2392 return; 2393 } 2394 } 2395 2396 GrowableArray<Block*>* successors = NULL; 2397 if (control != ciBlock::fall_through_bci) { 2398 // Check for exceptional control flow from this point. 2399 if (has_exceptions && can_trap(str)) { 2400 flow_exceptions(exceptions, exc_klasses, state); 2401 exceptions_used = true; 2402 } 2403 2404 // Fix the JsrSet to reflect effect of the bytecode. 2405 block->copy_jsrs_into(jsrs); 2406 jsrs->apply_control(this, &str, state); 2407 2408 // Find successor edges based on old state and new JsrSet. 2409 successors = block->successors(&str, state, jsrs); 2410 2411 // Apply the control changes to the state. 2412 state->apply_one_bytecode(&str); 2413 } else { 2414 // Fall through control 2415 successors = block->successors(&str, NULL, NULL); 2416 } 2417 2418 // Save set of locals defined in this block 2419 block->def_locals()->add(state->def_locals()); 2420 2421 // Remove untaken exception paths 2422 if (!exceptions_used) 2423 exceptions->clear(); 2424 2425 // Pass our state to successors. 2426 flow_successors(successors, state); 2427 } 2428 2429 // ------------------------------------------------------------------ 2430 // ciTypeFlow::PostOrderLoops::next 2431 // 2432 // Advance to next loop tree using a postorder, left-to-right traversal. 2433 void ciTypeFlow::PostorderLoops::next() { 2434 assert(!done(), "must not be done."); 2435 if (_current->sibling() != NULL) { 2436 _current = _current->sibling(); 2437 while (_current->child() != NULL) { 2438 _current = _current->child(); 2439 } 2440 } else { 2441 _current = _current->parent(); 2442 } 2443 } 2444 2445 // ------------------------------------------------------------------ 2446 // ciTypeFlow::PreOrderLoops::next 2447 // 2448 // Advance to next loop tree using a preorder, left-to-right traversal. 2449 void ciTypeFlow::PreorderLoops::next() { 2450 assert(!done(), "must not be done."); 2451 if (_current->child() != NULL) { 2452 _current = _current->child(); 2453 } else if (_current->sibling() != NULL) { 2454 _current = _current->sibling(); 2455 } else { 2456 while (_current != _root && _current->sibling() == NULL) { 2457 _current = _current->parent(); 2458 } 2459 if (_current == _root) { 2460 _current = NULL; 2461 assert(done(), "must be done."); 2462 } else { 2463 assert(_current->sibling() != NULL, "must be more to do"); 2464 _current = _current->sibling(); 2465 } 2466 } 2467 } 2468 2469 // ------------------------------------------------------------------ 2470 // ciTypeFlow::Loop::sorted_merge 2471 // 2472 // Merge the branch lp into this branch, sorting on the loop head 2473 // pre_orders. Returns the leaf of the merged branch. 2474 // Child and sibling pointers will be setup later. 2475 // Sort is (looking from leaf towards the root) 2476 // descending on primary key: loop head's pre_order, and 2477 // ascending on secondary key: loop tail's pre_order. 2478 ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) { 2479 Loop* leaf = this; 2480 Loop* prev = NULL; 2481 Loop* current = leaf; 2482 while (lp != NULL) { 2483 int lp_pre_order = lp->head()->pre_order(); 2484 // Find insertion point for "lp" 2485 while (current != NULL) { 2486 if (current == lp) 2487 return leaf; // Already in list 2488 if (current->head()->pre_order() < lp_pre_order) 2489 break; 2490 if (current->head()->pre_order() == lp_pre_order && 2491 current->tail()->pre_order() > lp->tail()->pre_order()) { 2492 break; 2493 } 2494 prev = current; 2495 current = current->parent(); 2496 } 2497 Loop* next_lp = lp->parent(); // Save future list of items to insert 2498 // Insert lp before current 2499 lp->set_parent(current); 2500 if (prev != NULL) { 2501 prev->set_parent(lp); 2502 } else { 2503 leaf = lp; 2504 } 2505 prev = lp; // Inserted item is new prev[ious] 2506 lp = next_lp; // Next item to insert 2507 } 2508 return leaf; 2509 } 2510 2511 // ------------------------------------------------------------------ 2512 // ciTypeFlow::build_loop_tree 2513 // 2514 // Incrementally build loop tree. 2515 void ciTypeFlow::build_loop_tree(Block* blk) { 2516 assert(!blk->is_post_visited(), "precondition"); 2517 Loop* innermost = NULL; // merge of loop tree branches over all successors 2518 2519 for (SuccIter iter(blk); !iter.done(); iter.next()) { 2520 Loop* lp = NULL; 2521 Block* succ = iter.succ(); 2522 if (!succ->is_post_visited()) { 2523 // Found backedge since predecessor post visited, but successor is not 2524 assert(succ->pre_order() <= blk->pre_order(), "should be backedge"); 2525 2526 // Create a LoopNode to mark this loop. 2527 lp = new (arena()) Loop(succ, blk); 2528 if (succ->loop() == NULL) 2529 succ->set_loop(lp); 2530 // succ->loop will be updated to innermost loop on a later call, when blk==succ 2531 2532 } else { // Nested loop 2533 lp = succ->loop(); 2534 2535 // If succ is loop head, find outer loop. 2536 while (lp != NULL && lp->head() == succ) { 2537 lp = lp->parent(); 2538 } 2539 if (lp == NULL) { 2540 // Infinite loop, it's parent is the root 2541 lp = loop_tree_root(); 2542 } 2543 } 2544 2545 // Check for irreducible loop. 2546 // Successor has already been visited. If the successor's loop head 2547 // has already been post-visited, then this is another entry into the loop. 2548 while (lp->head()->is_post_visited() && lp != loop_tree_root()) { 2549 _has_irreducible_entry = true; 2550 lp->set_irreducible(succ); 2551 if (!succ->is_on_work_list()) { 2552 // Assume irreducible entries need more data flow 2553 add_to_work_list(succ); 2554 } 2555 Loop* plp = lp->parent(); 2556 if (plp == NULL) { 2557 // This only happens for some irreducible cases. The parent 2558 // will be updated during a later pass. 2559 break; 2560 } 2561 lp = plp; 2562 } 2563 2564 // Merge loop tree branch for all successors. 2565 innermost = innermost == NULL ? lp : innermost->sorted_merge(lp); 2566 2567 } // end loop 2568 2569 if (innermost == NULL) { 2570 assert(blk->successors()->length() == 0, "CFG exit"); 2571 blk->set_loop(loop_tree_root()); 2572 } else if (innermost->head() == blk) { 2573 // If loop header, complete the tree pointers 2574 if (blk->loop() != innermost) { 2575 #ifdef ASSERT 2576 assert(blk->loop()->head() == innermost->head(), "same head"); 2577 Loop* dl; 2578 for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent()); 2579 assert(dl == blk->loop(), "blk->loop() already in innermost list"); 2580 #endif 2581 blk->set_loop(innermost); 2582 } 2583 innermost->def_locals()->add(blk->def_locals()); 2584 Loop* l = innermost; 2585 Loop* p = l->parent(); 2586 while (p && l->head() == blk) { 2587 l->set_sibling(p->child()); // Put self on parents 'next child' 2588 p->set_child(l); // Make self the first child of parent 2589 p->def_locals()->add(l->def_locals()); 2590 l = p; // Walk up the parent chain 2591 p = l->parent(); 2592 } 2593 } else { 2594 blk->set_loop(innermost); 2595 innermost->def_locals()->add(blk->def_locals()); 2596 } 2597 } 2598 2599 // ------------------------------------------------------------------ 2600 // ciTypeFlow::Loop::contains 2601 // 2602 // Returns true if lp is nested loop. 2603 bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const { 2604 assert(lp != NULL, ""); 2605 if (this == lp || head() == lp->head()) return true; 2606 int depth1 = depth(); 2607 int depth2 = lp->depth(); 2608 if (depth1 > depth2) 2609 return false; 2610 while (depth1 < depth2) { 2611 depth2--; 2612 lp = lp->parent(); 2613 } 2614 return this == lp; 2615 } 2616 2617 // ------------------------------------------------------------------ 2618 // ciTypeFlow::Loop::depth 2619 // 2620 // Loop depth 2621 int ciTypeFlow::Loop::depth() const { 2622 int dp = 0; 2623 for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent()) 2624 dp++; 2625 return dp; 2626 } 2627 2628 #ifndef PRODUCT 2629 // ------------------------------------------------------------------ 2630 // ciTypeFlow::Loop::print 2631 void ciTypeFlow::Loop::print(outputStream* st, int indent) const { 2632 for (int i = 0; i < indent; i++) st->print(" "); 2633 st->print("%d<-%d %s", 2634 is_root() ? 0 : this->head()->pre_order(), 2635 is_root() ? 0 : this->tail()->pre_order(), 2636 is_irreducible()?" irr":""); 2637 st->print(" defs: "); 2638 def_locals()->print_on(st, _head->outer()->method()->max_locals()); 2639 st->cr(); 2640 for (Loop* ch = child(); ch != NULL; ch = ch->sibling()) 2641 ch->print(st, indent+2); 2642 } 2643 #endif 2644 2645 // ------------------------------------------------------------------ 2646 // ciTypeFlow::df_flow_types 2647 // 2648 // Perform the depth first type flow analysis. Helper for flow_types. 2649 void ciTypeFlow::df_flow_types(Block* start, 2650 bool do_flow, 2651 StateVector* temp_vector, 2652 JsrSet* temp_set) { 2653 int dft_len = 100; 2654 GrowableArray<Block*> stk(dft_len); 2655 2656 ciBlock* dummy = _methodBlocks->make_dummy_block(); 2657 JsrSet* root_set = new JsrSet(NULL, 0); 2658 Block* root_head = new (arena()) Block(this, dummy, root_set); 2659 Block* root_tail = new (arena()) Block(this, dummy, root_set); 2660 root_head->set_pre_order(0); 2661 root_head->set_post_order(0); 2662 root_tail->set_pre_order(max_jint); 2663 root_tail->set_post_order(max_jint); 2664 set_loop_tree_root(new (arena()) Loop(root_head, root_tail)); 2665 2666 stk.push(start); 2667 2668 _next_pre_order = 0; // initialize pre_order counter 2669 _rpo_list = NULL; 2670 int next_po = 0; // initialize post_order counter 2671 2672 // Compute RPO and the control flow graph 2673 int size; 2674 while ((size = stk.length()) > 0) { 2675 Block* blk = stk.top(); // Leave node on stack 2676 if (!blk->is_visited()) { 2677 // forward arc in graph 2678 assert (!blk->has_pre_order(), ""); 2679 blk->set_next_pre_order(); 2680 2681 if (_next_pre_order >= (int)Compile::current()->max_node_limit() / 2) { 2682 // Too many basic blocks. Bail out. 2683 // This can happen when try/finally constructs are nested to depth N, 2684 // and there is O(2**N) cloning of jsr bodies. See bug 4697245! 2685 // "MaxNodeLimit / 2" is used because probably the parser will 2686 // generate at least twice that many nodes and bail out. 2687 record_failure("too many basic blocks"); 2688 return; 2689 } 2690 if (do_flow) { 2691 flow_block(blk, temp_vector, temp_set); 2692 if (failing()) return; // Watch for bailouts. 2693 } 2694 } else if (!blk->is_post_visited()) { 2695 // cross or back arc 2696 for (SuccIter iter(blk); !iter.done(); iter.next()) { 2697 Block* succ = iter.succ(); 2698 if (!succ->is_visited()) { 2699 stk.push(succ); 2700 } 2701 } 2702 if (stk.length() == size) { 2703 // There were no additional children, post visit node now 2704 stk.pop(); // Remove node from stack 2705 2706 build_loop_tree(blk); 2707 blk->set_post_order(next_po++); // Assign post order 2708 prepend_to_rpo_list(blk); 2709 assert(blk->is_post_visited(), ""); 2710 2711 if (blk->is_loop_head() && !blk->is_on_work_list()) { 2712 // Assume loop heads need more data flow 2713 add_to_work_list(blk); 2714 } 2715 } 2716 } else { 2717 stk.pop(); // Remove post-visited node from stack 2718 } 2719 } 2720 } 2721 2722 // ------------------------------------------------------------------ 2723 // ciTypeFlow::flow_types 2724 // 2725 // Perform the type flow analysis, creating and cloning Blocks as 2726 // necessary. 2727 void ciTypeFlow::flow_types() { 2728 ResourceMark rm; 2729 StateVector* temp_vector = new StateVector(this); 2730 JsrSet* temp_set = new JsrSet(NULL, 16); 2731 2732 // Create the method entry block. 2733 Block* start = block_at(start_bci(), temp_set); 2734 2735 // Load the initial state into it. 2736 const StateVector* start_state = get_start_state(); 2737 if (failing()) return; 2738 start->meet(start_state); 2739 2740 // Depth first visit 2741 df_flow_types(start, true /*do flow*/, temp_vector, temp_set); 2742 2743 if (failing()) return; 2744 assert(_rpo_list == start, "must be start"); 2745 2746 // Any loops found? 2747 if (loop_tree_root()->child() != NULL && 2748 env()->comp_level() >= CompLevel_full_optimization) { 2749 // Loop optimizations are not performed on Tier1 compiles. 2750 2751 bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set); 2752 2753 // If some loop heads were cloned, recompute postorder and loop tree 2754 if (changed) { 2755 loop_tree_root()->set_child(NULL); 2756 for (Block* blk = _rpo_list; blk != NULL;) { 2757 Block* next = blk->rpo_next(); 2758 blk->df_init(); 2759 blk = next; 2760 } 2761 df_flow_types(start, false /*no flow*/, temp_vector, temp_set); 2762 } 2763 } 2764 2765 if (CITraceTypeFlow) { 2766 tty->print_cr("\nLoop tree"); 2767 loop_tree_root()->print(); 2768 } 2769 2770 // Continue flow analysis until fixed point reached 2771 2772 debug_only(int max_block = _next_pre_order;) 2773 2774 while (!work_list_empty()) { 2775 Block* blk = work_list_next(); 2776 assert (blk->has_post_order(), "post order assigned above"); 2777 2778 flow_block(blk, temp_vector, temp_set); 2779 2780 assert (max_block == _next_pre_order, "no new blocks"); 2781 assert (!failing(), "no more bailouts"); 2782 } 2783 } 2784 2785 // ------------------------------------------------------------------ 2786 // ciTypeFlow::map_blocks 2787 // 2788 // Create the block map, which indexes blocks in reverse post-order. 2789 void ciTypeFlow::map_blocks() { 2790 assert(_block_map == NULL, "single initialization"); 2791 int block_ct = _next_pre_order; 2792 _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct); 2793 assert(block_ct == block_count(), ""); 2794 2795 Block* blk = _rpo_list; 2796 for (int m = 0; m < block_ct; m++) { 2797 int rpo = blk->rpo(); 2798 assert(rpo == m, "should be sequential"); 2799 _block_map[rpo] = blk; 2800 blk = blk->rpo_next(); 2801 } 2802 assert(blk == NULL, "should be done"); 2803 2804 for (int j = 0; j < block_ct; j++) { 2805 assert(_block_map[j] != NULL, "must not drop any blocks"); 2806 Block* block = _block_map[j]; 2807 // Remove dead blocks from successor lists: 2808 for (int e = 0; e <= 1; e++) { 2809 GrowableArray<Block*>* l = e? block->exceptions(): block->successors(); 2810 for (int k = 0; k < l->length(); k++) { 2811 Block* s = l->at(k); 2812 if (!s->has_post_order()) { 2813 if (CITraceTypeFlow) { 2814 tty->print("Removing dead %s successor of #%d: ", (e? "exceptional": "normal"), block->pre_order()); 2815 s->print_value_on(tty); 2816 tty->cr(); 2817 } 2818 l->remove(s); 2819 --k; 2820 } 2821 } 2822 } 2823 } 2824 } 2825 2826 // ------------------------------------------------------------------ 2827 // ciTypeFlow::get_block_for 2828 // 2829 // Find a block with this ciBlock which has a compatible JsrSet. 2830 // If no such block exists, create it, unless the option is no_create. 2831 // If the option is create_backedge_copy, always create a fresh backedge copy. 2832 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) { 2833 Arena* a = arena(); 2834 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex]; 2835 if (blocks == NULL) { 2836 // Query only? 2837 if (option == no_create) return NULL; 2838 2839 // Allocate the growable array. 2840 blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL); 2841 _idx_to_blocklist[ciBlockIndex] = blocks; 2842 } 2843 2844 if (option != create_backedge_copy) { 2845 int len = blocks->length(); 2846 for (int i = 0; i < len; i++) { 2847 Block* block = blocks->at(i); 2848 if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) { 2849 return block; 2850 } 2851 } 2852 } 2853 2854 // Query only? 2855 if (option == no_create) return NULL; 2856 2857 // We did not find a compatible block. Create one. 2858 Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs); 2859 if (option == create_backedge_copy) new_block->set_backedge_copy(true); 2860 blocks->append(new_block); 2861 return new_block; 2862 } 2863 2864 // ------------------------------------------------------------------ 2865 // ciTypeFlow::backedge_copy_count 2866 // 2867 int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const { 2868 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex]; 2869 2870 if (blocks == NULL) { 2871 return 0; 2872 } 2873 2874 int count = 0; 2875 int len = blocks->length(); 2876 for (int i = 0; i < len; i++) { 2877 Block* block = blocks->at(i); 2878 if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) { 2879 count++; 2880 } 2881 } 2882 2883 return count; 2884 } 2885 2886 // ------------------------------------------------------------------ 2887 // ciTypeFlow::do_flow 2888 // 2889 // Perform type inference flow analysis. 2890 void ciTypeFlow::do_flow() { 2891 if (CITraceTypeFlow) { 2892 tty->print_cr("\nPerforming flow analysis on method"); 2893 method()->print(); 2894 if (is_osr_flow()) tty->print(" at OSR bci %d", start_bci()); 2895 tty->cr(); 2896 method()->print_codes(); 2897 } 2898 if (CITraceTypeFlow) { 2899 tty->print_cr("Initial CI Blocks"); 2900 print_on(tty); 2901 } 2902 flow_types(); 2903 // Watch for bailouts. 2904 if (failing()) { 2905 return; 2906 } 2907 2908 map_blocks(); 2909 2910 if (CIPrintTypeFlow || CITraceTypeFlow) { 2911 rpo_print_on(tty); 2912 } 2913 } 2914 2915 // ------------------------------------------------------------------ 2916 // ciTypeFlow::is_dominated_by 2917 // 2918 // Determine if the instruction at bci is dominated by the instruction at dom_bci. 2919 bool ciTypeFlow::is_dominated_by(int bci, int dom_bci) { 2920 assert(!method()->has_jsrs(), "jsrs are not supported"); 2921 2922 ResourceMark rm; 2923 JsrSet* jsrs = new ciTypeFlow::JsrSet(NULL); 2924 int index = _methodBlocks->block_containing(bci)->index(); 2925 int dom_index = _methodBlocks->block_containing(dom_bci)->index(); 2926 Block* block = get_block_for(index, jsrs, ciTypeFlow::no_create); 2927 Block* dom_block = get_block_for(dom_index, jsrs, ciTypeFlow::no_create); 2928 2929 // Start block dominates all other blocks 2930 if (start_block()->rpo() == dom_block->rpo()) { 2931 return true; 2932 } 2933 2934 // Dominated[i] is true if block i is dominated by dom_block 2935 int num_blocks = block_count(); 2936 bool* dominated = NEW_RESOURCE_ARRAY(bool, num_blocks); 2937 for (int i = 0; i < num_blocks; ++i) { 2938 dominated[i] = true; 2939 } 2940 dominated[start_block()->rpo()] = false; 2941 2942 // Iterative dominator algorithm 2943 bool changed = true; 2944 while (changed) { 2945 changed = false; 2946 // Use reverse postorder iteration 2947 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) { 2948 if (blk->is_start()) { 2949 // Ignore start block 2950 continue; 2951 } 2952 // The block is dominated if it is the dominating block 2953 // itself or if all predecessors are dominated. 2954 int index = blk->rpo(); 2955 bool dom = (index == dom_block->rpo()); 2956 if (!dom) { 2957 // Check if all predecessors are dominated 2958 dom = true; 2959 for (int i = 0; i < blk->predecessors()->length(); ++i) { 2960 Block* pred = blk->predecessors()->at(i); 2961 if (!dominated[pred->rpo()]) { 2962 dom = false; 2963 break; 2964 } 2965 } 2966 } 2967 // Update dominator information 2968 if (dominated[index] != dom) { 2969 changed = true; 2970 dominated[index] = dom; 2971 } 2972 } 2973 } 2974 // block dominated by dom_block? 2975 return dominated[block->rpo()]; 2976 } 2977 2978 // ------------------------------------------------------------------ 2979 // ciTypeFlow::record_failure() 2980 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv. 2981 // This is required because there is not a 1-1 relation between the ciEnv and 2982 // the TypeFlow passes within a compilation task. For example, if the compiler 2983 // is considering inlining a method, it will request a TypeFlow. If that fails, 2984 // the compilation as a whole may continue without the inlining. Some TypeFlow 2985 // requests are not optional; if they fail the requestor is responsible for 2986 // copying the failure reason up to the ciEnv. (See Parse::Parse.) 2987 void ciTypeFlow::record_failure(const char* reason) { 2988 if (env()->log() != NULL) { 2989 env()->log()->elem("failure reason='%s' phase='typeflow'", reason); 2990 } 2991 if (_failure_reason == NULL) { 2992 // Record the first failure reason. 2993 _failure_reason = reason; 2994 } 2995 } 2996 2997 #ifndef PRODUCT 2998 // ------------------------------------------------------------------ 2999 // ciTypeFlow::print_on 3000 void ciTypeFlow::print_on(outputStream* st) const { 3001 // Walk through CI blocks 3002 st->print_cr("********************************************************"); 3003 st->print ("TypeFlow for "); 3004 method()->name()->print_symbol_on(st); 3005 int limit_bci = code_size(); 3006 st->print_cr(" %d bytes", limit_bci); 3007 ciMethodBlocks *mblks = _methodBlocks; 3008 ciBlock* current = NULL; 3009 for (int bci = 0; bci < limit_bci; bci++) { 3010 ciBlock* blk = mblks->block_containing(bci); 3011 if (blk != NULL && blk != current) { 3012 current = blk; 3013 current->print_on(st); 3014 3015 GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()]; 3016 int num_blocks = (blocks == NULL) ? 0 : blocks->length(); 3017 3018 if (num_blocks == 0) { 3019 st->print_cr(" No Blocks"); 3020 } else { 3021 for (int i = 0; i < num_blocks; i++) { 3022 Block* block = blocks->at(i); 3023 block->print_on(st); 3024 } 3025 } 3026 st->print_cr("--------------------------------------------------------"); 3027 st->cr(); 3028 } 3029 } 3030 st->print_cr("********************************************************"); 3031 st->cr(); 3032 } 3033 3034 void ciTypeFlow::rpo_print_on(outputStream* st) const { 3035 st->print_cr("********************************************************"); 3036 st->print ("TypeFlow for "); 3037 method()->name()->print_symbol_on(st); 3038 int limit_bci = code_size(); 3039 st->print_cr(" %d bytes", limit_bci); 3040 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) { 3041 blk->print_on(st); 3042 st->print_cr("--------------------------------------------------------"); 3043 st->cr(); 3044 } 3045 st->print_cr("********************************************************"); 3046 st->cr(); 3047 } 3048 #endif