1/* 2 * Copyright (c) 2005, 2016, 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/ciArrayKlass.hpp" 27#include "ci/ciEnv.hpp" 28#include "ci/ciKlass.hpp" 29#include "ci/ciMethod.hpp" 30#include "classfile/javaClasses.inline.hpp" 31#include "code/dependencies.hpp" 32#include "compiler/compileLog.hpp" 33#include "memory/resourceArea.hpp" 34#include "oops/oop.inline.hpp" 35#include "oops/objArrayKlass.hpp" 36#include "runtime/handles.hpp" 37#include "runtime/handles.inline.hpp" 38#include "runtime/thread.inline.hpp" 39#include "utilities/copy.hpp" 40 41 42#ifdef ASSERT 43static bool must_be_in_vm() { 44 Thread* thread = Thread::current(); 45 if (thread->is_Java_thread()) 46 return ((JavaThread*)thread)->thread_state() == _thread_in_vm; 47 else 48 return true; //something like this: thread->is_VM_thread(); 49} 50#endif //ASSERT 51 52void Dependencies::initialize(ciEnv* env) { 53 Arena* arena = env->arena(); 54 _oop_recorder = env->oop_recorder(); 55 _log = env->log(); 56 _dep_seen = new(arena) GrowableArray<int>(arena, 500, 0, 0); 57#if INCLUDE_JVMCI 58 _using_dep_values = false; 59#endif 60 DEBUG_ONLY(_deps[end_marker] = NULL); 61 for (int i = (int)FIRST_TYPE; i < (int)TYPE_LIMIT; i++) { 62 _deps[i] = new(arena) GrowableArray<ciBaseObject*>(arena, 10, 0, 0); 63 } 64 _content_bytes = NULL; 65 _size_in_bytes = (size_t)-1; 66 67 assert(TYPE_LIMIT <= (1<<LG2_TYPE_LIMIT), "sanity"); 68} 69 70void Dependencies::assert_evol_method(ciMethod* m) { 71 assert_common_1(evol_method, m); 72} 73 74void Dependencies::assert_leaf_type(ciKlass* ctxk) { 75 if (ctxk->is_array_klass()) { 76 // As a special case, support this assertion on an array type, 77 // which reduces to an assertion on its element type. 78 // Note that this cannot be done with assertions that 79 // relate to concreteness or abstractness. 80 ciType* elemt = ctxk->as_array_klass()->base_element_type(); 81 if (!elemt->is_instance_klass()) return; // Ex: int[][] 82 ctxk = elemt->as_instance_klass(); 83 //if (ctxk->is_final()) return; // Ex: String[][] 84 } 85 check_ctxk(ctxk); 86 assert_common_1(leaf_type, ctxk); 87} 88 89void Dependencies::assert_abstract_with_unique_concrete_subtype(ciKlass* ctxk, ciKlass* conck) { 90 check_ctxk_abstract(ctxk); 91 assert_common_2(abstract_with_unique_concrete_subtype, ctxk, conck); 92} 93 94void Dependencies::assert_abstract_with_no_concrete_subtype(ciKlass* ctxk) { 95 check_ctxk_abstract(ctxk); 96 assert_common_1(abstract_with_no_concrete_subtype, ctxk); 97} 98 99void Dependencies::assert_concrete_with_no_concrete_subtype(ciKlass* ctxk) { 100 check_ctxk_concrete(ctxk); 101 assert_common_1(concrete_with_no_concrete_subtype, ctxk); 102} 103 104void Dependencies::assert_unique_concrete_method(ciKlass* ctxk, ciMethod* uniqm) { 105 check_ctxk(ctxk); 106 assert_common_2(unique_concrete_method, ctxk, uniqm); 107} 108 109void Dependencies::assert_abstract_with_exclusive_concrete_subtypes(ciKlass* ctxk, ciKlass* k1, ciKlass* k2) { 110 check_ctxk(ctxk); 111 assert_common_3(abstract_with_exclusive_concrete_subtypes_2, ctxk, k1, k2); 112} 113 114void Dependencies::assert_exclusive_concrete_methods(ciKlass* ctxk, ciMethod* m1, ciMethod* m2) { 115 check_ctxk(ctxk); 116 assert_common_3(exclusive_concrete_methods_2, ctxk, m1, m2); 117} 118 119void Dependencies::assert_has_no_finalizable_subclasses(ciKlass* ctxk) { 120 check_ctxk(ctxk); 121 assert_common_1(no_finalizable_subclasses, ctxk); 122} 123 124void Dependencies::assert_call_site_target_value(ciCallSite* call_site, ciMethodHandle* method_handle) { 125 assert_common_2(call_site_target_value, call_site, method_handle); 126} 127 128#if INCLUDE_JVMCI 129 130Dependencies::Dependencies(Arena* arena, OopRecorder* oop_recorder, CompileLog* log) { 131 _oop_recorder = oop_recorder; 132 _log = log; 133 _dep_seen = new(arena) GrowableArray<int>(arena, 500, 0, 0); 134 _using_dep_values = true; 135 DEBUG_ONLY(_dep_values[end_marker] = NULL); 136 for (int i = (int)FIRST_TYPE; i < (int)TYPE_LIMIT; i++) { 137 _dep_values[i] = new(arena) GrowableArray<DepValue>(arena, 10, 0, DepValue()); 138 } 139 _content_bytes = NULL; 140 _size_in_bytes = (size_t)-1; 141 142 assert(TYPE_LIMIT <= (1<<LG2_TYPE_LIMIT), "sanity"); 143} 144 145void Dependencies::assert_evol_method(Method* m) { 146 assert_common_1(evol_method, DepValue(_oop_recorder, m)); 147} 148 149void Dependencies::assert_has_no_finalizable_subclasses(Klass* ctxk) { 150 check_ctxk(ctxk); 151 assert_common_1(no_finalizable_subclasses, DepValue(_oop_recorder, ctxk)); 152} 153 154void Dependencies::assert_leaf_type(Klass* ctxk) { 155 if (ctxk->is_array_klass()) { 156 // As a special case, support this assertion on an array type, 157 // which reduces to an assertion on its element type. 158 // Note that this cannot be done with assertions that 159 // relate to concreteness or abstractness. 160 BasicType elemt = ArrayKlass::cast(ctxk)->element_type(); 161 if (is_java_primitive(elemt)) return; // Ex: int[][] 162 ctxk = ObjArrayKlass::cast(ctxk)->bottom_klass(); 163 //if (ctxk->is_final()) return; // Ex: String[][] 164 } 165 check_ctxk(ctxk); 166 assert_common_1(leaf_type, DepValue(_oop_recorder, ctxk)); 167} 168 169void Dependencies::assert_abstract_with_unique_concrete_subtype(Klass* ctxk, Klass* conck) { 170 check_ctxk_abstract(ctxk); 171 DepValue ctxk_dv(_oop_recorder, ctxk); 172 DepValue conck_dv(_oop_recorder, conck, &ctxk_dv); 173 assert_common_2(abstract_with_unique_concrete_subtype, ctxk_dv, conck_dv); 174} 175 176void Dependencies::assert_unique_concrete_method(Klass* ctxk, Method* uniqm) { 177 check_ctxk(ctxk); 178 assert_common_2(unique_concrete_method, DepValue(_oop_recorder, ctxk), DepValue(_oop_recorder, uniqm)); 179} 180 181void Dependencies::assert_call_site_target_value(oop call_site, oop method_handle) { 182 assert_common_2(call_site_target_value, DepValue(_oop_recorder, JNIHandles::make_local(call_site)), DepValue(_oop_recorder, JNIHandles::make_local(method_handle))); 183} 184 185#endif // INCLUDE_JVMCI 186 187 188// Helper function. If we are adding a new dep. under ctxk2, 189// try to find an old dep. under a broader* ctxk1. If there is 190// 191bool Dependencies::maybe_merge_ctxk(GrowableArray<ciBaseObject*>* deps, 192 int ctxk_i, ciKlass* ctxk2) { 193 ciKlass* ctxk1 = deps->at(ctxk_i)->as_metadata()->as_klass(); 194 if (ctxk2->is_subtype_of(ctxk1)) { 195 return true; // success, and no need to change 196 } else if (ctxk1->is_subtype_of(ctxk2)) { 197 // new context class fully subsumes previous one 198 deps->at_put(ctxk_i, ctxk2); 199 return true; 200 } else { 201 return false; 202 } 203} 204 205void Dependencies::assert_common_1(DepType dept, ciBaseObject* x) { 206 assert(dep_args(dept) == 1, "sanity"); 207 log_dependency(dept, x); 208 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 209 210 // see if the same (or a similar) dep is already recorded 211 if (note_dep_seen(dept, x)) { 212 assert(deps->find(x) >= 0, "sanity"); 213 } else { 214 deps->append(x); 215 } 216} 217 218void Dependencies::assert_common_2(DepType dept, 219 ciBaseObject* x0, ciBaseObject* x1) { 220 assert(dep_args(dept) == 2, "sanity"); 221 log_dependency(dept, x0, x1); 222 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 223 224 // see if the same (or a similar) dep is already recorded 225 bool has_ctxk = has_explicit_context_arg(dept); 226 if (has_ctxk) { 227 assert(dep_context_arg(dept) == 0, "sanity"); 228 if (note_dep_seen(dept, x1)) { 229 // look in this bucket for redundant assertions 230 const int stride = 2; 231 for (int i = deps->length(); (i -= stride) >= 0; ) { 232 ciBaseObject* y1 = deps->at(i+1); 233 if (x1 == y1) { // same subject; check the context 234 if (maybe_merge_ctxk(deps, i+0, x0->as_metadata()->as_klass())) { 235 return; 236 } 237 } 238 } 239 } 240 } else { 241 if (note_dep_seen(dept, x0) && note_dep_seen(dept, x1)) { 242 // look in this bucket for redundant assertions 243 const int stride = 2; 244 for (int i = deps->length(); (i -= stride) >= 0; ) { 245 ciBaseObject* y0 = deps->at(i+0); 246 ciBaseObject* y1 = deps->at(i+1); 247 if (x0 == y0 && x1 == y1) { 248 return; 249 } 250 } 251 } 252 } 253 254 // append the assertion in the correct bucket: 255 deps->append(x0); 256 deps->append(x1); 257} 258 259void Dependencies::assert_common_3(DepType dept, 260 ciKlass* ctxk, ciBaseObject* x, ciBaseObject* x2) { 261 assert(dep_context_arg(dept) == 0, "sanity"); 262 assert(dep_args(dept) == 3, "sanity"); 263 log_dependency(dept, ctxk, x, x2); 264 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 265 266 // try to normalize an unordered pair: 267 bool swap = false; 268 switch (dept) { 269 case abstract_with_exclusive_concrete_subtypes_2: 270 swap = (x->ident() > x2->ident() && x->as_metadata()->as_klass() != ctxk); 271 break; 272 case exclusive_concrete_methods_2: 273 swap = (x->ident() > x2->ident() && x->as_metadata()->as_method()->holder() != ctxk); 274 break; 275 } 276 if (swap) { ciBaseObject* t = x; x = x2; x2 = t; } 277 278 // see if the same (or a similar) dep is already recorded 279 if (note_dep_seen(dept, x) && note_dep_seen(dept, x2)) { 280 // look in this bucket for redundant assertions 281 const int stride = 3; 282 for (int i = deps->length(); (i -= stride) >= 0; ) { 283 ciBaseObject* y = deps->at(i+1); 284 ciBaseObject* y2 = deps->at(i+2); 285 if (x == y && x2 == y2) { // same subjects; check the context 286 if (maybe_merge_ctxk(deps, i+0, ctxk)) { 287 return; 288 } 289 } 290 } 291 } 292 // append the assertion in the correct bucket: 293 deps->append(ctxk); 294 deps->append(x); 295 deps->append(x2); 296} 297 298#if INCLUDE_JVMCI 299bool Dependencies::maybe_merge_ctxk(GrowableArray<DepValue>* deps, 300 int ctxk_i, DepValue ctxk2_dv) { 301 Klass* ctxk1 = deps->at(ctxk_i).as_klass(_oop_recorder); 302 Klass* ctxk2 = ctxk2_dv.as_klass(_oop_recorder); 303 if (ctxk2->is_subtype_of(ctxk1)) { 304 return true; // success, and no need to change 305 } else if (ctxk1->is_subtype_of(ctxk2)) { 306 // new context class fully subsumes previous one 307 deps->at_put(ctxk_i, ctxk2_dv); 308 return true; 309 } else { 310 return false; 311 } 312} 313 314void Dependencies::assert_common_1(DepType dept, DepValue x) { 315 assert(dep_args(dept) == 1, "sanity"); 316 //log_dependency(dept, x); 317 GrowableArray<DepValue>* deps = _dep_values[dept]; 318 319 // see if the same (or a similar) dep is already recorded 320 if (note_dep_seen(dept, x)) { 321 assert(deps->find(x) >= 0, "sanity"); 322 } else { 323 deps->append(x); 324 } 325} 326 327void Dependencies::assert_common_2(DepType dept, 328 DepValue x0, DepValue x1) { 329 assert(dep_args(dept) == 2, "sanity"); 330 //log_dependency(dept, x0, x1); 331 GrowableArray<DepValue>* deps = _dep_values[dept]; 332 333 // see if the same (or a similar) dep is already recorded 334 bool has_ctxk = has_explicit_context_arg(dept); 335 if (has_ctxk) { 336 assert(dep_context_arg(dept) == 0, "sanity"); 337 if (note_dep_seen(dept, x1)) { 338 // look in this bucket for redundant assertions 339 const int stride = 2; 340 for (int i = deps->length(); (i -= stride) >= 0; ) { 341 DepValue y1 = deps->at(i+1); 342 if (x1 == y1) { // same subject; check the context 343 if (maybe_merge_ctxk(deps, i+0, x0)) { 344 return; 345 } 346 } 347 } 348 } 349 } else { 350 if (note_dep_seen(dept, x0) && note_dep_seen(dept, x1)) { 351 // look in this bucket for redundant assertions 352 const int stride = 2; 353 for (int i = deps->length(); (i -= stride) >= 0; ) { 354 DepValue y0 = deps->at(i+0); 355 DepValue y1 = deps->at(i+1); 356 if (x0 == y0 && x1 == y1) { 357 return; 358 } 359 } 360 } 361 } 362 363 // append the assertion in the correct bucket: 364 deps->append(x0); 365 deps->append(x1); 366} 367#endif // INCLUDE_JVMCI 368 369/// Support for encoding dependencies into an nmethod: 370 371void Dependencies::copy_to(nmethod* nm) { 372 address beg = nm->dependencies_begin(); 373 address end = nm->dependencies_end(); 374 guarantee(end - beg >= (ptrdiff_t) size_in_bytes(), "bad sizing"); 375 Copy::disjoint_words((HeapWord*) content_bytes(), 376 (HeapWord*) beg, 377 size_in_bytes() / sizeof(HeapWord)); 378 assert(size_in_bytes() % sizeof(HeapWord) == 0, "copy by words"); 379} 380 381static int sort_dep(ciBaseObject** p1, ciBaseObject** p2, int narg) { 382 for (int i = 0; i < narg; i++) { 383 int diff = p1[i]->ident() - p2[i]->ident(); 384 if (diff != 0) return diff; 385 } 386 return 0; 387} 388static int sort_dep_arg_1(ciBaseObject** p1, ciBaseObject** p2) 389{ return sort_dep(p1, p2, 1); } 390static int sort_dep_arg_2(ciBaseObject** p1, ciBaseObject** p2) 391{ return sort_dep(p1, p2, 2); } 392static int sort_dep_arg_3(ciBaseObject** p1, ciBaseObject** p2) 393{ return sort_dep(p1, p2, 3); } 394 395#if INCLUDE_JVMCI 396// metadata deps are sorted before object deps 397static int sort_dep_value(Dependencies::DepValue* p1, Dependencies::DepValue* p2, int narg) { 398 for (int i = 0; i < narg; i++) { 399 int diff = p1[i].sort_key() - p2[i].sort_key(); 400 if (diff != 0) return diff; 401 } 402 return 0; 403} 404static int sort_dep_value_arg_1(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 405{ return sort_dep_value(p1, p2, 1); } 406static int sort_dep_value_arg_2(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 407{ return sort_dep_value(p1, p2, 2); } 408static int sort_dep_value_arg_3(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 409{ return sort_dep_value(p1, p2, 3); } 410#endif // INCLUDE_JVMCI 411 412void Dependencies::sort_all_deps() { 413#if INCLUDE_JVMCI 414 if (_using_dep_values) { 415 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 416 DepType dept = (DepType)deptv; 417 GrowableArray<DepValue>* deps = _dep_values[dept]; 418 if (deps->length() <= 1) continue; 419 switch (dep_args(dept)) { 420 case 1: deps->sort(sort_dep_value_arg_1, 1); break; 421 case 2: deps->sort(sort_dep_value_arg_2, 2); break; 422 case 3: deps->sort(sort_dep_value_arg_3, 3); break; 423 default: ShouldNotReachHere(); 424 } 425 } 426 return; 427 } 428#endif // INCLUDE_JVMCI 429 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 430 DepType dept = (DepType)deptv; 431 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 432 if (deps->length() <= 1) continue; 433 switch (dep_args(dept)) { 434 case 1: deps->sort(sort_dep_arg_1, 1); break; 435 case 2: deps->sort(sort_dep_arg_2, 2); break; 436 case 3: deps->sort(sort_dep_arg_3, 3); break; 437 default: ShouldNotReachHere(); 438 } 439 } 440} 441 442size_t Dependencies::estimate_size_in_bytes() { 443 size_t est_size = 100; 444#if INCLUDE_JVMCI 445 if (_using_dep_values) { 446 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 447 DepType dept = (DepType)deptv; 448 GrowableArray<DepValue>* deps = _dep_values[dept]; 449 est_size += deps->length() * 2; // tags and argument(s) 450 } 451 return est_size; 452 } 453#endif // INCLUDE_JVMCI 454 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 455 DepType dept = (DepType)deptv; 456 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 457 est_size += deps->length()*2; // tags and argument(s) 458 } 459 return est_size; 460} 461 462ciKlass* Dependencies::ctxk_encoded_as_null(DepType dept, ciBaseObject* x) { 463 switch (dept) { 464 case abstract_with_exclusive_concrete_subtypes_2: 465 return x->as_metadata()->as_klass(); 466 case unique_concrete_method: 467 case exclusive_concrete_methods_2: 468 return x->as_metadata()->as_method()->holder(); 469 } 470 return NULL; // let NULL be NULL 471} 472 473Klass* Dependencies::ctxk_encoded_as_null(DepType dept, Metadata* x) { 474 assert(must_be_in_vm(), "raw oops here"); 475 switch (dept) { 476 case abstract_with_exclusive_concrete_subtypes_2: 477 assert(x->is_klass(), "sanity"); 478 return (Klass*) x; 479 case unique_concrete_method: 480 case exclusive_concrete_methods_2: 481 assert(x->is_method(), "sanity"); 482 return ((Method*)x)->method_holder(); 483 } 484 return NULL; // let NULL be NULL 485} 486 487void Dependencies::encode_content_bytes() { 488 sort_all_deps(); 489 490 // cast is safe, no deps can overflow INT_MAX 491 CompressedWriteStream bytes((int)estimate_size_in_bytes()); 492 493#if INCLUDE_JVMCI 494 if (_using_dep_values) { 495 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 496 DepType dept = (DepType)deptv; 497 GrowableArray<DepValue>* deps = _dep_values[dept]; 498 if (deps->length() == 0) continue; 499 int stride = dep_args(dept); 500 int ctxkj = dep_context_arg(dept); // -1 if no context arg 501 assert(stride > 0, "sanity"); 502 for (int i = 0; i < deps->length(); i += stride) { 503 jbyte code_byte = (jbyte)dept; 504 int skipj = -1; 505 if (ctxkj >= 0 && ctxkj+1 < stride) { 506 Klass* ctxk = deps->at(i+ctxkj+0).as_klass(_oop_recorder); 507 DepValue x = deps->at(i+ctxkj+1); // following argument 508 if (ctxk == ctxk_encoded_as_null(dept, x.as_metadata(_oop_recorder))) { 509 skipj = ctxkj; // we win: maybe one less oop to keep track of 510 code_byte |= default_context_type_bit; 511 } 512 } 513 bytes.write_byte(code_byte); 514 for (int j = 0; j < stride; j++) { 515 if (j == skipj) continue; 516 DepValue v = deps->at(i+j); 517 int idx = v.index(); 518 bytes.write_int(idx); 519 } 520 } 521 } 522 } else { 523#endif // INCLUDE_JVMCI 524 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 525 DepType dept = (DepType)deptv; 526 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 527 if (deps->length() == 0) continue; 528 int stride = dep_args(dept); 529 int ctxkj = dep_context_arg(dept); // -1 if no context arg 530 assert(stride > 0, "sanity"); 531 for (int i = 0; i < deps->length(); i += stride) { 532 jbyte code_byte = (jbyte)dept; 533 int skipj = -1; 534 if (ctxkj >= 0 && ctxkj+1 < stride) { 535 ciKlass* ctxk = deps->at(i+ctxkj+0)->as_metadata()->as_klass(); 536 ciBaseObject* x = deps->at(i+ctxkj+1); // following argument 537 if (ctxk == ctxk_encoded_as_null(dept, x)) { 538 skipj = ctxkj; // we win: maybe one less oop to keep track of 539 code_byte |= default_context_type_bit; 540 } 541 } 542 bytes.write_byte(code_byte); 543 for (int j = 0; j < stride; j++) { 544 if (j == skipj) continue; 545 ciBaseObject* v = deps->at(i+j); 546 int idx; 547 if (v->is_object()) { 548 idx = _oop_recorder->find_index(v->as_object()->constant_encoding()); 549 } else { 550 ciMetadata* meta = v->as_metadata(); 551 idx = _oop_recorder->find_index(meta->constant_encoding()); 552 } 553 bytes.write_int(idx); 554 } 555 } 556 } 557#if INCLUDE_JVMCI 558 } 559#endif 560 561 // write a sentinel byte to mark the end 562 bytes.write_byte(end_marker); 563 564 // round it out to a word boundary 565 while (bytes.position() % sizeof(HeapWord) != 0) { 566 bytes.write_byte(end_marker); 567 } 568 569 // check whether the dept byte encoding really works 570 assert((jbyte)default_context_type_bit != 0, "byte overflow"); 571 572 _content_bytes = bytes.buffer(); 573 _size_in_bytes = bytes.position(); 574} 575 576 577const char* Dependencies::_dep_name[TYPE_LIMIT] = { 578 "end_marker", 579 "evol_method", 580 "leaf_type", 581 "abstract_with_unique_concrete_subtype", 582 "abstract_with_no_concrete_subtype", 583 "concrete_with_no_concrete_subtype", 584 "unique_concrete_method", 585 "abstract_with_exclusive_concrete_subtypes_2", 586 "exclusive_concrete_methods_2", 587 "no_finalizable_subclasses", 588 "call_site_target_value" 589}; 590 591int Dependencies::_dep_args[TYPE_LIMIT] = { 592 -1,// end_marker 593 1, // evol_method m 594 1, // leaf_type ctxk 595 2, // abstract_with_unique_concrete_subtype ctxk, k 596 1, // abstract_with_no_concrete_subtype ctxk 597 1, // concrete_with_no_concrete_subtype ctxk 598 2, // unique_concrete_method ctxk, m 599 3, // unique_concrete_subtypes_2 ctxk, k1, k2 600 3, // unique_concrete_methods_2 ctxk, m1, m2 601 1, // no_finalizable_subclasses ctxk 602 2 // call_site_target_value call_site, method_handle 603}; 604 605const char* Dependencies::dep_name(Dependencies::DepType dept) { 606 if (!dept_in_mask(dept, all_types)) return "?bad-dep?"; 607 return _dep_name[dept]; 608} 609 610int Dependencies::dep_args(Dependencies::DepType dept) { 611 if (!dept_in_mask(dept, all_types)) return -1; 612 return _dep_args[dept]; 613} 614 615void Dependencies::check_valid_dependency_type(DepType dept) { 616 guarantee(FIRST_TYPE <= dept && dept < TYPE_LIMIT, "invalid dependency type: %d", (int) dept); 617} 618 619// for the sake of the compiler log, print out current dependencies: 620void Dependencies::log_all_dependencies() { 621 if (log() == NULL) return; 622 ResourceMark rm; 623 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 624 DepType dept = (DepType)deptv; 625 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 626 int deplen = deps->length(); 627 if (deplen == 0) { 628 continue; 629 } 630 int stride = dep_args(dept); 631 GrowableArray<ciBaseObject*>* ciargs = new GrowableArray<ciBaseObject*>(stride); 632 for (int i = 0; i < deps->length(); i += stride) { 633 for (int j = 0; j < stride; j++) { 634 // flush out the identities before printing 635 ciargs->push(deps->at(i+j)); 636 } 637 write_dependency_to(log(), dept, ciargs); 638 ciargs->clear(); 639 } 640 guarantee(deplen == deps->length(), "deps array cannot grow inside nested ResoureMark scope"); 641 } 642} 643 644void Dependencies::write_dependency_to(CompileLog* log, 645 DepType dept, 646 GrowableArray<DepArgument>* args, 647 Klass* witness) { 648 if (log == NULL) { 649 return; 650 } 651 ResourceMark rm; 652 ciEnv* env = ciEnv::current(); 653 GrowableArray<ciBaseObject*>* ciargs = new GrowableArray<ciBaseObject*>(args->length()); 654 for (GrowableArrayIterator<DepArgument> it = args->begin(); it != args->end(); ++it) { 655 DepArgument arg = *it; 656 if (arg.is_oop()) { 657 ciargs->push(env->get_object(arg.oop_value())); 658 } else { 659 ciargs->push(env->get_metadata(arg.metadata_value())); 660 } 661 } 662 int argslen = ciargs->length(); 663 Dependencies::write_dependency_to(log, dept, ciargs, witness); 664 guarantee(argslen == ciargs->length(), "ciargs array cannot grow inside nested ResoureMark scope"); 665} 666 667void Dependencies::write_dependency_to(CompileLog* log, 668 DepType dept, 669 GrowableArray<ciBaseObject*>* args, 670 Klass* witness) { 671 if (log == NULL) { 672 return; 673 } 674 ResourceMark rm; 675 GrowableArray<int>* argids = new GrowableArray<int>(args->length()); 676 for (GrowableArrayIterator<ciBaseObject*> it = args->begin(); it != args->end(); ++it) { 677 ciBaseObject* obj = *it; 678 if (obj->is_object()) { 679 argids->push(log->identify(obj->as_object())); 680 } else { 681 argids->push(log->identify(obj->as_metadata())); 682 } 683 } 684 if (witness != NULL) { 685 log->begin_elem("dependency_failed"); 686 } else { 687 log->begin_elem("dependency"); 688 } 689 log->print(" type='%s'", dep_name(dept)); 690 const int ctxkj = dep_context_arg(dept); // -1 if no context arg 691 if (ctxkj >= 0 && ctxkj < argids->length()) { 692 log->print(" ctxk='%d'", argids->at(ctxkj)); 693 } 694 // write remaining arguments, if any. 695 for (int j = 0; j < argids->length(); j++) { 696 if (j == ctxkj) continue; // already logged 697 if (j == 1) { 698 log->print( " x='%d'", argids->at(j)); 699 } else { 700 log->print(" x%d='%d'", j, argids->at(j)); 701 } 702 } 703 if (witness != NULL) { 704 log->object("witness", witness); 705 log->stamp(); 706 } 707 log->end_elem(); 708} 709 710void Dependencies::write_dependency_to(xmlStream* xtty, 711 DepType dept, 712 GrowableArray<DepArgument>* args, 713 Klass* witness) { 714 if (xtty == NULL) { 715 return; 716 } 717 ResourceMark rm; 718 ttyLocker ttyl; 719 int ctxkj = dep_context_arg(dept); // -1 if no context arg 720 if (witness != NULL) { 721 xtty->begin_elem("dependency_failed"); 722 } else { 723 xtty->begin_elem("dependency"); 724 } 725 xtty->print(" type='%s'", dep_name(dept)); 726 if (ctxkj >= 0) { 727 xtty->object("ctxk", args->at(ctxkj).metadata_value()); 728 } 729 // write remaining arguments, if any. 730 for (int j = 0; j < args->length(); j++) { 731 if (j == ctxkj) continue; // already logged 732 DepArgument arg = args->at(j); 733 if (j == 1) { 734 if (arg.is_oop()) { 735 xtty->object("x", arg.oop_value()); 736 } else { 737 xtty->object("x", arg.metadata_value()); 738 } 739 } else { 740 char xn[10]; sprintf(xn, "x%d", j); 741 if (arg.is_oop()) { 742 xtty->object(xn, arg.oop_value()); 743 } else { 744 xtty->object(xn, arg.metadata_value()); 745 } 746 } 747 } 748 if (witness != NULL) { 749 xtty->object("witness", witness); 750 xtty->stamp(); 751 } 752 xtty->end_elem(); 753} 754 755void Dependencies::print_dependency(DepType dept, GrowableArray<DepArgument>* args, 756 Klass* witness, outputStream* st) { 757 ResourceMark rm; 758 ttyLocker ttyl; // keep the following output all in one block 759 st->print_cr("%s of type %s", 760 (witness == NULL)? "Dependency": "Failed dependency", 761 dep_name(dept)); 762 // print arguments 763 int ctxkj = dep_context_arg(dept); // -1 if no context arg 764 for (int j = 0; j < args->length(); j++) { 765 DepArgument arg = args->at(j); 766 bool put_star = false; 767 if (arg.is_null()) continue; 768 const char* what; 769 if (j == ctxkj) { 770 assert(arg.is_metadata(), "must be"); 771 what = "context"; 772 put_star = !Dependencies::is_concrete_klass((Klass*)arg.metadata_value()); 773 } else if (arg.is_method()) { 774 what = "method "; 775 put_star = !Dependencies::is_concrete_method((Method*)arg.metadata_value(), NULL); 776 } else if (arg.is_klass()) { 777 what = "class "; 778 } else { 779 what = "object "; 780 } 781 st->print(" %s = %s", what, (put_star? "*": "")); 782 if (arg.is_klass()) { 783 st->print("%s", ((Klass*)arg.metadata_value())->external_name()); 784 } else if (arg.is_method()) { 785 ((Method*)arg.metadata_value())->print_value_on(st); 786 } else if (arg.is_oop()) { 787 arg.oop_value()->print_value_on(st); 788 } else { 789 ShouldNotReachHere(); // Provide impl for this type. 790 } 791 792 st->cr(); 793 } 794 if (witness != NULL) { 795 bool put_star = !Dependencies::is_concrete_klass(witness); 796 st->print_cr(" witness = %s%s", 797 (put_star? "*": ""), 798 witness->external_name()); 799 } 800} 801 802void Dependencies::DepStream::log_dependency(Klass* witness) { 803 if (_deps == NULL && xtty == NULL) return; // fast cutout for runtime 804 ResourceMark rm; 805 const int nargs = argument_count(); 806 GrowableArray<DepArgument>* args = new GrowableArray<DepArgument>(nargs); 807 for (int j = 0; j < nargs; j++) { 808 if (is_oop_argument(j)) { 809 args->push(argument_oop(j)); 810 } else { 811 args->push(argument(j)); 812 } 813 } 814 int argslen = args->length(); 815 if (_deps != NULL && _deps->log() != NULL) { 816 if (ciEnv::current() != NULL) { 817 Dependencies::write_dependency_to(_deps->log(), type(), args, witness); 818 } else { 819 // Treat the CompileLog as an xmlstream instead 820 Dependencies::write_dependency_to((xmlStream*)_deps->log(), type(), args, witness); 821 } 822 } else { 823 Dependencies::write_dependency_to(xtty, type(), args, witness); 824 } 825 guarantee(argslen == args->length(), "args array cannot grow inside nested ResoureMark scope"); 826} 827 828void Dependencies::DepStream::print_dependency(Klass* witness, bool verbose, outputStream* st) { 829 ResourceMark rm; 830 int nargs = argument_count(); 831 GrowableArray<DepArgument>* args = new GrowableArray<DepArgument>(nargs); 832 for (int j = 0; j < nargs; j++) { 833 if (is_oop_argument(j)) { 834 args->push(argument_oop(j)); 835 } else { 836 args->push(argument(j)); 837 } 838 } 839 int argslen = args->length(); 840 Dependencies::print_dependency(type(), args, witness, st); 841 if (verbose) { 842 if (_code != NULL) { 843 st->print(" code: "); 844 _code->print_value_on(st); 845 st->cr(); 846 } 847 } 848 guarantee(argslen == args->length(), "args array cannot grow inside nested ResoureMark scope"); 849} 850 851 852/// Dependency stream support (decodes dependencies from an nmethod): 853 854#ifdef ASSERT 855void Dependencies::DepStream::initial_asserts(size_t byte_limit) { 856 assert(must_be_in_vm(), "raw oops here"); 857 _byte_limit = byte_limit; 858 _type = (DepType)(end_marker-1); // defeat "already at end" assert 859 assert((_code!=NULL) + (_deps!=NULL) == 1, "one or t'other"); 860} 861#endif //ASSERT 862 863bool Dependencies::DepStream::next() { 864 assert(_type != end_marker, "already at end"); 865 if (_bytes.position() == 0 && _code != NULL 866 && _code->dependencies_size() == 0) { 867 // Method has no dependencies at all. 868 return false; 869 } 870 int code_byte = (_bytes.read_byte() & 0xFF); 871 if (code_byte == end_marker) { 872 DEBUG_ONLY(_type = end_marker); 873 return false; 874 } else { 875 int ctxk_bit = (code_byte & Dependencies::default_context_type_bit); 876 code_byte -= ctxk_bit; 877 DepType dept = (DepType)code_byte; 878 _type = dept; 879 Dependencies::check_valid_dependency_type(dept); 880 int stride = _dep_args[dept]; 881 assert(stride == dep_args(dept), "sanity"); 882 int skipj = -1; 883 if (ctxk_bit != 0) { 884 skipj = 0; // currently the only context argument is at zero 885 assert(skipj == dep_context_arg(dept), "zero arg always ctxk"); 886 } 887 for (int j = 0; j < stride; j++) { 888 _xi[j] = (j == skipj)? 0: _bytes.read_int(); 889 } 890 DEBUG_ONLY(_xi[stride] = -1); // help detect overruns 891 return true; 892 } 893} 894 895inline Metadata* Dependencies::DepStream::recorded_metadata_at(int i) { 896 Metadata* o = NULL; 897 if (_code != NULL) { 898 o = _code->metadata_at(i); 899 } else { 900 o = _deps->oop_recorder()->metadata_at(i); 901 } 902 return o; 903} 904 905inline oop Dependencies::DepStream::recorded_oop_at(int i) { 906 return (_code != NULL) 907 ? _code->oop_at(i) 908 : JNIHandles::resolve(_deps->oop_recorder()->oop_at(i)); 909} 910 911Metadata* Dependencies::DepStream::argument(int i) { 912 Metadata* result = recorded_metadata_at(argument_index(i)); 913 914 if (result == NULL) { // Explicit context argument can be compressed 915 int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg 916 if (ctxkj >= 0 && i == ctxkj && ctxkj+1 < argument_count()) { 917 result = ctxk_encoded_as_null(type(), argument(ctxkj+1)); 918 } 919 } 920 921 assert(result == NULL || result->is_klass() || result->is_method(), "must be"); 922 return result; 923} 924 925/** 926 * Returns a unique identifier for each dependency argument. 927 */ 928uintptr_t Dependencies::DepStream::get_identifier(int i) { 929 if (is_oop_argument(i)) { 930 return (uintptr_t)(oopDesc*)argument_oop(i); 931 } else { 932 return (uintptr_t)argument(i); 933 } 934} 935 936oop Dependencies::DepStream::argument_oop(int i) { 937 oop result = recorded_oop_at(argument_index(i)); 938 assert(result == NULL || result->is_oop(), "must be"); 939 return result; 940} 941 942Klass* Dependencies::DepStream::context_type() { 943 assert(must_be_in_vm(), "raw oops here"); 944 945 // Most dependencies have an explicit context type argument. 946 { 947 int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg 948 if (ctxkj >= 0) { 949 Metadata* k = argument(ctxkj); 950 assert(k != NULL && k->is_klass(), "type check"); 951 return (Klass*)k; 952 } 953 } 954 955 // Some dependencies are using the klass of the first object 956 // argument as implicit context type. 957 { 958 int ctxkj = dep_implicit_context_arg(type()); 959 if (ctxkj >= 0) { 960 Klass* k = argument_oop(ctxkj)->klass(); 961 assert(k != NULL && k->is_klass(), "type check"); 962 return (Klass*) k; 963 } 964 } 965 966 // And some dependencies don't have a context type at all, 967 // e.g. evol_method. 968 return NULL; 969} 970 971// ----------------- DependencySignature -------------------------------------- 972bool DependencySignature::equals(DependencySignature const& s1, DependencySignature const& s2) { 973 if ((s1.type() != s2.type()) || (s1.args_count() != s2.args_count())) { 974 return false; 975 } 976 977 for (int i = 0; i < s1.args_count(); i++) { 978 if (s1.arg(i) != s2.arg(i)) { 979 return false; 980 } 981 } 982 return true; 983} 984 985/// Checking dependencies: 986 987// This hierarchy walker inspects subtypes of a given type, 988// trying to find a "bad" class which breaks a dependency. 989// Such a class is called a "witness" to the broken dependency. 990// While searching around, we ignore "participants", which 991// are already known to the dependency. 992class ClassHierarchyWalker { 993 public: 994 enum { PARTICIPANT_LIMIT = 3 }; 995 996 private: 997 // optional method descriptor to check for: 998 Symbol* _name; 999 Symbol* _signature; 1000 1001 // special classes which are not allowed to be witnesses: 1002 Klass* _participants[PARTICIPANT_LIMIT+1]; 1003 int _num_participants; 1004 1005 // cache of method lookups 1006 Method* _found_methods[PARTICIPANT_LIMIT+1]; 1007 1008 // if non-zero, tells how many witnesses to convert to participants 1009 int _record_witnesses; 1010 1011 void initialize(Klass* participant) { 1012 _record_witnesses = 0; 1013 _participants[0] = participant; 1014 _found_methods[0] = NULL; 1015 _num_participants = 0; 1016 if (participant != NULL) { 1017 // Terminating NULL. 1018 _participants[1] = NULL; 1019 _found_methods[1] = NULL; 1020 _num_participants = 1; 1021 } 1022 } 1023 1024 void initialize_from_method(Method* m) { 1025 assert(m != NULL && m->is_method(), "sanity"); 1026 _name = m->name(); 1027 _signature = m->signature(); 1028 } 1029 1030 public: 1031 // The walker is initialized to recognize certain methods and/or types 1032 // as friendly participants. 1033 ClassHierarchyWalker(Klass* participant, Method* m) { 1034 initialize_from_method(m); 1035 initialize(participant); 1036 } 1037 ClassHierarchyWalker(Method* m) { 1038 initialize_from_method(m); 1039 initialize(NULL); 1040 } 1041 ClassHierarchyWalker(Klass* participant = NULL) { 1042 _name = NULL; 1043 _signature = NULL; 1044 initialize(participant); 1045 } 1046 1047 // This is common code for two searches: One for concrete subtypes, 1048 // the other for concrete method implementations and overrides. 1049 bool doing_subtype_search() { 1050 return _name == NULL; 1051 } 1052 1053 int num_participants() { return _num_participants; } 1054 Klass* participant(int n) { 1055 assert((uint)n <= (uint)_num_participants, "oob"); 1056 return _participants[n]; 1057 } 1058 1059 // Note: If n==num_participants, returns NULL. 1060 Method* found_method(int n) { 1061 assert((uint)n <= (uint)_num_participants, "oob"); 1062 Method* fm = _found_methods[n]; 1063 assert(n == _num_participants || fm != NULL, "proper usage"); 1064 if (fm != NULL && fm->method_holder() != _participants[n]) { 1065 // Default methods from interfaces can be added to classes. In 1066 // that case the holder of the method is not the class but the 1067 // interface where it's defined. 1068 assert(fm->is_default_method(), "sanity"); 1069 return NULL; 1070 } 1071 return fm; 1072 } 1073 1074#ifdef ASSERT 1075 // Assert that m is inherited into ctxk, without intervening overrides. 1076 // (May return true even if this is not true, in corner cases where we punt.) 1077 bool check_method_context(Klass* ctxk, Method* m) { 1078 if (m->method_holder() == ctxk) 1079 return true; // Quick win. 1080 if (m->is_private()) 1081 return false; // Quick lose. Should not happen. 1082 if (!(m->is_public() || m->is_protected())) 1083 // The override story is complex when packages get involved. 1084 return true; // Must punt the assertion to true. 1085 Method* lm = ctxk->lookup_method(m->name(), m->signature()); 1086 if (lm == NULL && ctxk->is_instance_klass()) { 1087 // It might be an interface method 1088 lm = InstanceKlass::cast(ctxk)->lookup_method_in_ordered_interfaces(m->name(), 1089 m->signature()); 1090 } 1091 if (lm == m) 1092 // Method m is inherited into ctxk. 1093 return true; 1094 if (lm != NULL) { 1095 if (!(lm->is_public() || lm->is_protected())) { 1096 // Method is [package-]private, so the override story is complex. 1097 return true; // Must punt the assertion to true. 1098 } 1099 if (lm->is_static()) { 1100 // Static methods don't override non-static so punt 1101 return true; 1102 } 1103 if (!Dependencies::is_concrete_method(lm, ctxk) && 1104 !Dependencies::is_concrete_method(m, ctxk)) { 1105 // They are both non-concrete 1106 if (lm->method_holder()->is_subtype_of(m->method_holder())) { 1107 // Method m is overridden by lm, but both are non-concrete. 1108 return true; 1109 } 1110 if (lm->method_holder()->is_interface() && m->method_holder()->is_interface() && 1111 ctxk->is_subtype_of(m->method_holder()) && ctxk->is_subtype_of(lm->method_holder())) { 1112 // Interface method defined in multiple super interfaces 1113 return true; 1114 } 1115 } 1116 } 1117 ResourceMark rm; 1118 tty->print_cr("Dependency method not found in the associated context:"); 1119 tty->print_cr(" context = %s", ctxk->external_name()); 1120 tty->print( " method = "); m->print_short_name(tty); tty->cr(); 1121 if (lm != NULL) { 1122 tty->print( " found = "); lm->print_short_name(tty); tty->cr(); 1123 } 1124 return false; 1125 } 1126#endif 1127 1128 void add_participant(Klass* participant) { 1129 assert(_num_participants + _record_witnesses < PARTICIPANT_LIMIT, "oob"); 1130 int np = _num_participants++; 1131 _participants[np] = participant; 1132 _participants[np+1] = NULL; 1133 _found_methods[np+1] = NULL; 1134 } 1135 1136 void record_witnesses(int add) { 1137 if (add > PARTICIPANT_LIMIT) add = PARTICIPANT_LIMIT; 1138 assert(_num_participants + add < PARTICIPANT_LIMIT, "oob"); 1139 _record_witnesses = add; 1140 } 1141 1142 bool is_witness(Klass* k) { 1143 if (doing_subtype_search()) { 1144 return Dependencies::is_concrete_klass(k); 1145 } else if (!k->is_instance_klass()) { 1146 return false; // no methods to find in an array type 1147 } else { 1148 // Search class hierarchy first. 1149 Method* m = InstanceKlass::cast(k)->find_instance_method(_name, _signature); 1150 if (!Dependencies::is_concrete_method(m, k)) { 1151 // Check interface defaults also, if any exist. 1152 Array<Method*>* default_methods = InstanceKlass::cast(k)->default_methods(); 1153 if (default_methods == NULL) 1154 return false; 1155 m = InstanceKlass::cast(k)->find_method(default_methods, _name, _signature); 1156 if (!Dependencies::is_concrete_method(m, NULL)) 1157 return false; 1158 } 1159 _found_methods[_num_participants] = m; 1160 // Note: If add_participant(k) is called, 1161 // the method m will already be memoized for it. 1162 return true; 1163 } 1164 } 1165 1166 bool is_participant(Klass* k) { 1167 if (k == _participants[0]) { 1168 return true; 1169 } else if (_num_participants <= 1) { 1170 return false; 1171 } else { 1172 return in_list(k, &_participants[1]); 1173 } 1174 } 1175 bool ignore_witness(Klass* witness) { 1176 if (_record_witnesses == 0) { 1177 return false; 1178 } else { 1179 --_record_witnesses; 1180 add_participant(witness); 1181 return true; 1182 } 1183 } 1184 static bool in_list(Klass* x, Klass** list) { 1185 for (int i = 0; ; i++) { 1186 Klass* y = list[i]; 1187 if (y == NULL) break; 1188 if (y == x) return true; 1189 } 1190 return false; // not in list 1191 } 1192 1193 private: 1194 // the actual search method: 1195 Klass* find_witness_anywhere(Klass* context_type, 1196 bool participants_hide_witnesses, 1197 bool top_level_call = true); 1198 // the spot-checking version: 1199 Klass* find_witness_in(KlassDepChange& changes, 1200 Klass* context_type, 1201 bool participants_hide_witnesses); 1202 public: 1203 Klass* find_witness_subtype(Klass* context_type, KlassDepChange* changes = NULL) { 1204 assert(doing_subtype_search(), "must set up a subtype search"); 1205 // When looking for unexpected concrete types, 1206 // do not look beneath expected ones. 1207 const bool participants_hide_witnesses = true; 1208 // CX > CC > C' is OK, even if C' is new. 1209 // CX > { CC, C' } is not OK if C' is new, and C' is the witness. 1210 if (changes != NULL) { 1211 return find_witness_in(*changes, context_type, participants_hide_witnesses); 1212 } else { 1213 return find_witness_anywhere(context_type, participants_hide_witnesses); 1214 } 1215 } 1216 Klass* find_witness_definer(Klass* context_type, KlassDepChange* changes = NULL) { 1217 assert(!doing_subtype_search(), "must set up a method definer search"); 1218 // When looking for unexpected concrete methods, 1219 // look beneath expected ones, to see if there are overrides. 1220 const bool participants_hide_witnesses = true; 1221 // CX.m > CC.m > C'.m is not OK, if C'.m is new, and C' is the witness. 1222 if (changes != NULL) { 1223 return find_witness_in(*changes, context_type, !participants_hide_witnesses); 1224 } else { 1225 return find_witness_anywhere(context_type, !participants_hide_witnesses); 1226 } 1227 } 1228}; 1229 1230#ifndef PRODUCT 1231static int deps_find_witness_calls = 0; 1232static int deps_find_witness_steps = 0; 1233static int deps_find_witness_recursions = 0; 1234static int deps_find_witness_singles = 0; 1235static int deps_find_witness_print = 0; // set to -1 to force a final print 1236static bool count_find_witness_calls() { 1237 if (TraceDependencies || LogCompilation) { 1238 int pcount = deps_find_witness_print + 1; 1239 bool final_stats = (pcount == 0); 1240 bool initial_call = (pcount == 1); 1241 bool occasional_print = ((pcount & ((1<<10) - 1)) == 0); 1242 if (pcount < 0) pcount = 1; // crude overflow protection 1243 deps_find_witness_print = pcount; 1244 if (VerifyDependencies && initial_call) { 1245 tty->print_cr("Warning: TraceDependencies results may be inflated by VerifyDependencies"); 1246 } 1247 if (occasional_print || final_stats) { 1248 // Every now and then dump a little info about dependency searching. 1249 if (xtty != NULL) { 1250 ttyLocker ttyl; 1251 xtty->elem("deps_find_witness calls='%d' steps='%d' recursions='%d' singles='%d'", 1252 deps_find_witness_calls, 1253 deps_find_witness_steps, 1254 deps_find_witness_recursions, 1255 deps_find_witness_singles); 1256 } 1257 if (final_stats || (TraceDependencies && WizardMode)) { 1258 ttyLocker ttyl; 1259 tty->print_cr("Dependency check (find_witness) " 1260 "calls=%d, steps=%d (avg=%.1f), recursions=%d, singles=%d", 1261 deps_find_witness_calls, 1262 deps_find_witness_steps, 1263 (double)deps_find_witness_steps / deps_find_witness_calls, 1264 deps_find_witness_recursions, 1265 deps_find_witness_singles); 1266 } 1267 } 1268 return true; 1269 } 1270 return false; 1271} 1272#else 1273#define count_find_witness_calls() (0) 1274#endif //PRODUCT 1275 1276 1277Klass* ClassHierarchyWalker::find_witness_in(KlassDepChange& changes, 1278 Klass* context_type, 1279 bool participants_hide_witnesses) { 1280 assert(changes.involves_context(context_type), "irrelevant dependency"); 1281 Klass* new_type = changes.new_type(); 1282 1283 (void)count_find_witness_calls(); 1284 NOT_PRODUCT(deps_find_witness_singles++); 1285 1286 // Current thread must be in VM (not native mode, as in CI): 1287 assert(must_be_in_vm(), "raw oops here"); 1288 // Must not move the class hierarchy during this check: 1289 assert_locked_or_safepoint(Compile_lock); 1290 1291 int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); 1292 if (nof_impls > 1) { 1293 // Avoid this case: *I.m > { A.m, C }; B.m > C 1294 // %%% Until this is fixed more systematically, bail out. 1295 // See corresponding comment in find_witness_anywhere. 1296 return context_type; 1297 } 1298 1299 assert(!is_participant(new_type), "only old classes are participants"); 1300 if (participants_hide_witnesses) { 1301 // If the new type is a subtype of a participant, we are done. 1302 for (int i = 0; i < num_participants(); i++) { 1303 Klass* part = participant(i); 1304 if (part == NULL) continue; 1305 assert(changes.involves_context(part) == new_type->is_subtype_of(part), 1306 "correct marking of participants, b/c new_type is unique"); 1307 if (changes.involves_context(part)) { 1308 // new guy is protected from this check by previous participant 1309 return NULL; 1310 } 1311 } 1312 } 1313 1314 if (is_witness(new_type) && 1315 !ignore_witness(new_type)) { 1316 return new_type; 1317 } 1318 1319 return NULL; 1320} 1321 1322 1323// Walk hierarchy under a context type, looking for unexpected types. 1324// Do not report participant types, and recursively walk beneath 1325// them only if participants_hide_witnesses is false. 1326// If top_level_call is false, skip testing the context type, 1327// because the caller has already considered it. 1328Klass* ClassHierarchyWalker::find_witness_anywhere(Klass* context_type, 1329 bool participants_hide_witnesses, 1330 bool top_level_call) { 1331 // Current thread must be in VM (not native mode, as in CI): 1332 assert(must_be_in_vm(), "raw oops here"); 1333 // Must not move the class hierarchy during this check: 1334 assert_locked_or_safepoint(Compile_lock); 1335 1336 bool do_counts = count_find_witness_calls(); 1337 1338 // Check the root of the sub-hierarchy first. 1339 if (top_level_call) { 1340 if (do_counts) { 1341 NOT_PRODUCT(deps_find_witness_calls++); 1342 NOT_PRODUCT(deps_find_witness_steps++); 1343 } 1344 if (is_participant(context_type)) { 1345 if (participants_hide_witnesses) return NULL; 1346 // else fall through to search loop... 1347 } else if (is_witness(context_type) && !ignore_witness(context_type)) { 1348 // The context is an abstract class or interface, to start with. 1349 return context_type; 1350 } 1351 } 1352 1353 // Now we must check each implementor and each subclass. 1354 // Use a short worklist to avoid blowing the stack. 1355 // Each worklist entry is a *chain* of subklass siblings to process. 1356 const int CHAINMAX = 100; // >= 1 + InstanceKlass::implementors_limit 1357 Klass* chains[CHAINMAX]; 1358 int chaini = 0; // index into worklist 1359 Klass* chain; // scratch variable 1360#define ADD_SUBCLASS_CHAIN(k) { \ 1361 assert(chaini < CHAINMAX, "oob"); \ 1362 chain = k->subklass(); \ 1363 if (chain != NULL) chains[chaini++] = chain; } 1364 1365 // Look for non-abstract subclasses. 1366 // (Note: Interfaces do not have subclasses.) 1367 ADD_SUBCLASS_CHAIN(context_type); 1368 1369 // If it is an interface, search its direct implementors. 1370 // (Their subclasses are additional indirect implementors. 1371 // See InstanceKlass::add_implementor.) 1372 // (Note: nof_implementors is always zero for non-interfaces.) 1373 if (top_level_call) { 1374 int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); 1375 if (nof_impls > 1) { 1376 // Avoid this case: *I.m > { A.m, C }; B.m > C 1377 // Here, I.m has 2 concrete implementations, but m appears unique 1378 // as A.m, because the search misses B.m when checking C. 1379 // The inherited method B.m was getting missed by the walker 1380 // when interface 'I' was the starting point. 1381 // %%% Until this is fixed more systematically, bail out. 1382 // (Old CHA had the same limitation.) 1383 return context_type; 1384 } 1385 if (nof_impls > 0) { 1386 Klass* impl = InstanceKlass::cast(context_type)->implementor(); 1387 assert(impl != NULL, "just checking"); 1388 // If impl is the same as the context_type, then more than one 1389 // implementor has seen. No exact info in this case. 1390 if (impl == context_type) { 1391 return context_type; // report an inexact witness to this sad affair 1392 } 1393 if (do_counts) 1394 { NOT_PRODUCT(deps_find_witness_steps++); } 1395 if (is_participant(impl)) { 1396 if (!participants_hide_witnesses) { 1397 ADD_SUBCLASS_CHAIN(impl); 1398 } 1399 } else if (is_witness(impl) && !ignore_witness(impl)) { 1400 return impl; 1401 } else { 1402 ADD_SUBCLASS_CHAIN(impl); 1403 } 1404 } 1405 } 1406 1407 // Recursively process each non-trivial sibling chain. 1408 while (chaini > 0) { 1409 Klass* chain = chains[--chaini]; 1410 for (Klass* sub = chain; sub != NULL; sub = sub->next_sibling()) { 1411 if (do_counts) { NOT_PRODUCT(deps_find_witness_steps++); } 1412 if (is_participant(sub)) { 1413 if (participants_hide_witnesses) continue; 1414 // else fall through to process this guy's subclasses 1415 } else if (is_witness(sub) && !ignore_witness(sub)) { 1416 return sub; 1417 } 1418 if (chaini < (VerifyDependencies? 2: CHAINMAX)) { 1419 // Fast path. (Partially disabled if VerifyDependencies.) 1420 ADD_SUBCLASS_CHAIN(sub); 1421 } else { 1422 // Worklist overflow. Do a recursive call. Should be rare. 1423 // The recursive call will have its own worklist, of course. 1424 // (Note that sub has already been tested, so that there is 1425 // no need for the recursive call to re-test. That's handy, 1426 // since the recursive call sees sub as the context_type.) 1427 if (do_counts) { NOT_PRODUCT(deps_find_witness_recursions++); } 1428 Klass* witness = find_witness_anywhere(sub, 1429 participants_hide_witnesses, 1430 /*top_level_call=*/ false); 1431 if (witness != NULL) return witness; 1432 } 1433 } 1434 } 1435 1436 // No witness found. The dependency remains unbroken. 1437 return NULL; 1438#undef ADD_SUBCLASS_CHAIN 1439} 1440 1441 1442bool Dependencies::is_concrete_klass(Klass* k) { 1443 if (k->is_abstract()) return false; 1444 // %%% We could treat classes which are concrete but 1445 // have not yet been instantiated as virtually abstract. 1446 // This would require a deoptimization barrier on first instantiation. 1447 //if (k->is_not_instantiated()) return false; 1448 return true; 1449} 1450 1451bool Dependencies::is_concrete_method(Method* m, Klass * k) { 1452 // NULL is not a concrete method, 1453 // statics are irrelevant to virtual call sites, 1454 // abstract methods are not concrete, 1455 // overpass (error) methods are not concrete if k is abstract 1456 // 1457 // note "true" is conservative answer -- 1458 // overpass clause is false if k == NULL, implies return true if 1459 // answer depends on overpass clause. 1460 return ! ( m == NULL || m -> is_static() || m -> is_abstract() || 1461 m->is_overpass() && k != NULL && k -> is_abstract() ); 1462} 1463 1464 1465Klass* Dependencies::find_finalizable_subclass(Klass* k) { 1466 if (k->is_interface()) return NULL; 1467 if (k->has_finalizer()) return k; 1468 k = k->subklass(); 1469 while (k != NULL) { 1470 Klass* result = find_finalizable_subclass(k); 1471 if (result != NULL) return result; 1472 k = k->next_sibling(); 1473 } 1474 return NULL; 1475} 1476 1477 1478bool Dependencies::is_concrete_klass(ciInstanceKlass* k) { 1479 if (k->is_abstract()) return false; 1480 // We could also return false if k does not yet appear to be 1481 // instantiated, if the VM version supports this distinction also. 1482 //if (k->is_not_instantiated()) return false; 1483 return true; 1484} 1485 1486bool Dependencies::has_finalizable_subclass(ciInstanceKlass* k) { 1487 return k->has_finalizable_subclass(); 1488} 1489 1490 1491// Any use of the contents (bytecodes) of a method must be 1492// marked by an "evol_method" dependency, if those contents 1493// can change. (Note: A method is always dependent on itself.) 1494Klass* Dependencies::check_evol_method(Method* m) { 1495 assert(must_be_in_vm(), "raw oops here"); 1496 // Did somebody do a JVMTI RedefineClasses while our backs were turned? 1497 // Or is there a now a breakpoint? 1498 // (Assumes compiled code cannot handle bkpts; change if UseFastBreakpoints.) 1499 if (m->is_old() 1500 || m->number_of_breakpoints() > 0) { 1501 return m->method_holder(); 1502 } else { 1503 return NULL; 1504 } 1505} 1506 1507// This is a strong assertion: It is that the given type 1508// has no subtypes whatever. It is most useful for 1509// optimizing checks on reflected types or on array types. 1510// (Checks on types which are derived from real instances 1511// can be optimized more strongly than this, because we 1512// know that the checked type comes from a concrete type, 1513// and therefore we can disregard abstract types.) 1514Klass* Dependencies::check_leaf_type(Klass* ctxk) { 1515 assert(must_be_in_vm(), "raw oops here"); 1516 assert_locked_or_safepoint(Compile_lock); 1517 InstanceKlass* ctx = InstanceKlass::cast(ctxk); 1518 Klass* sub = ctx->subklass(); 1519 if (sub != NULL) { 1520 return sub; 1521 } else if (ctx->nof_implementors() != 0) { 1522 // if it is an interface, it must be unimplemented 1523 // (if it is not an interface, nof_implementors is always zero) 1524 Klass* impl = ctx->implementor(); 1525 assert(impl != NULL, "must be set"); 1526 return impl; 1527 } else { 1528 return NULL; 1529 } 1530} 1531 1532// Test the assertion that conck is the only concrete subtype* of ctxk. 1533// The type conck itself is allowed to have have further concrete subtypes. 1534// This allows the compiler to narrow occurrences of ctxk by conck, 1535// when dealing with the types of actual instances. 1536Klass* Dependencies::check_abstract_with_unique_concrete_subtype(Klass* ctxk, 1537 Klass* conck, 1538 KlassDepChange* changes) { 1539 ClassHierarchyWalker wf(conck); 1540 return wf.find_witness_subtype(ctxk, changes); 1541} 1542 1543// If a non-concrete class has no concrete subtypes, it is not (yet) 1544// instantiatable. This can allow the compiler to make some paths go 1545// dead, if they are gated by a test of the type. 1546Klass* Dependencies::check_abstract_with_no_concrete_subtype(Klass* ctxk, 1547 KlassDepChange* changes) { 1548 // Find any concrete subtype, with no participants: 1549 ClassHierarchyWalker wf; 1550 return wf.find_witness_subtype(ctxk, changes); 1551} 1552 1553 1554// If a concrete class has no concrete subtypes, it can always be 1555// exactly typed. This allows the use of a cheaper type test. 1556Klass* Dependencies::check_concrete_with_no_concrete_subtype(Klass* ctxk, 1557 KlassDepChange* changes) { 1558 // Find any concrete subtype, with only the ctxk as participant: 1559 ClassHierarchyWalker wf(ctxk); 1560 return wf.find_witness_subtype(ctxk, changes); 1561} 1562 1563 1564// Find the unique concrete proper subtype of ctxk, or NULL if there 1565// is more than one concrete proper subtype. If there are no concrete 1566// proper subtypes, return ctxk itself, whether it is concrete or not. 1567// The returned subtype is allowed to have have further concrete subtypes. 1568// That is, return CC1 for CX > CC1 > CC2, but NULL for CX > { CC1, CC2 }. 1569Klass* Dependencies::find_unique_concrete_subtype(Klass* ctxk) { 1570 ClassHierarchyWalker wf(ctxk); // Ignore ctxk when walking. 1571 wf.record_witnesses(1); // Record one other witness when walking. 1572 Klass* wit = wf.find_witness_subtype(ctxk); 1573 if (wit != NULL) return NULL; // Too many witnesses. 1574 Klass* conck = wf.participant(0); 1575 if (conck == NULL) { 1576#ifndef PRODUCT 1577 // Make sure the dependency mechanism will pass this discovery: 1578 if (VerifyDependencies) { 1579 // Turn off dependency tracing while actually testing deps. 1580 FlagSetting fs(TraceDependencies, false); 1581 if (!Dependencies::is_concrete_klass(ctxk)) { 1582 guarantee(NULL == 1583 (void *)check_abstract_with_no_concrete_subtype(ctxk), 1584 "verify dep."); 1585 } else { 1586 guarantee(NULL == 1587 (void *)check_concrete_with_no_concrete_subtype(ctxk), 1588 "verify dep."); 1589 } 1590 } 1591#endif //PRODUCT 1592 return ctxk; // Return ctxk as a flag for "no subtypes". 1593 } else { 1594#ifndef PRODUCT 1595 // Make sure the dependency mechanism will pass this discovery: 1596 if (VerifyDependencies) { 1597 // Turn off dependency tracing while actually testing deps. 1598 FlagSetting fs(TraceDependencies, false); 1599 if (!Dependencies::is_concrete_klass(ctxk)) { 1600 guarantee(NULL == (void *) 1601 check_abstract_with_unique_concrete_subtype(ctxk, conck), 1602 "verify dep."); 1603 } 1604 } 1605#endif //PRODUCT 1606 return conck; 1607 } 1608} 1609 1610// Test the assertion that the k[12] are the only concrete subtypes of ctxk, 1611// except possibly for further subtypes of k[12] themselves. 1612// The context type must be abstract. The types k1 and k2 are themselves 1613// allowed to have further concrete subtypes. 1614Klass* Dependencies::check_abstract_with_exclusive_concrete_subtypes( 1615 Klass* ctxk, 1616 Klass* k1, 1617 Klass* k2, 1618 KlassDepChange* changes) { 1619 ClassHierarchyWalker wf; 1620 wf.add_participant(k1); 1621 wf.add_participant(k2); 1622 return wf.find_witness_subtype(ctxk, changes); 1623} 1624 1625// Search ctxk for concrete implementations. If there are klen or fewer, 1626// pack them into the given array and return the number. 1627// Otherwise, return -1, meaning the given array would overflow. 1628// (Note that a return of 0 means there are exactly no concrete subtypes.) 1629// In this search, if ctxk is concrete, it will be reported alone. 1630// For any type CC reported, no proper subtypes of CC will be reported. 1631int Dependencies::find_exclusive_concrete_subtypes(Klass* ctxk, 1632 int klen, 1633 Klass* karray[]) { 1634 ClassHierarchyWalker wf; 1635 wf.record_witnesses(klen); 1636 Klass* wit = wf.find_witness_subtype(ctxk); 1637 if (wit != NULL) return -1; // Too many witnesses. 1638 int num = wf.num_participants(); 1639 assert(num <= klen, "oob"); 1640 // Pack the result array with the good news. 1641 for (int i = 0; i < num; i++) 1642 karray[i] = wf.participant(i); 1643#ifndef PRODUCT 1644 // Make sure the dependency mechanism will pass this discovery: 1645 if (VerifyDependencies) { 1646 // Turn off dependency tracing while actually testing deps. 1647 FlagSetting fs(TraceDependencies, false); 1648 switch (Dependencies::is_concrete_klass(ctxk)? -1: num) { 1649 case -1: // ctxk was itself concrete 1650 guarantee(num == 1 && karray[0] == ctxk, "verify dep."); 1651 break; 1652 case 0: 1653 guarantee(NULL == (void *)check_abstract_with_no_concrete_subtype(ctxk), 1654 "verify dep."); 1655 break; 1656 case 1: 1657 guarantee(NULL == (void *) 1658 check_abstract_with_unique_concrete_subtype(ctxk, karray[0]), 1659 "verify dep."); 1660 break; 1661 case 2: 1662 guarantee(NULL == (void *) 1663 check_abstract_with_exclusive_concrete_subtypes(ctxk, 1664 karray[0], 1665 karray[1]), 1666 "verify dep."); 1667 break; 1668 default: 1669 ShouldNotReachHere(); // klen > 2 yet supported 1670 } 1671 } 1672#endif //PRODUCT 1673 return num; 1674} 1675 1676// If a class (or interface) has a unique concrete method uniqm, return NULL. 1677// Otherwise, return a class that contains an interfering method. 1678Klass* Dependencies::check_unique_concrete_method(Klass* ctxk, Method* uniqm, 1679 KlassDepChange* changes) { 1680 // Here is a missing optimization: If uniqm->is_final(), 1681 // we don't really need to search beneath it for overrides. 1682 // This is probably not important, since we don't use dependencies 1683 // to track final methods. (They can't be "definalized".) 1684 ClassHierarchyWalker wf(uniqm->method_holder(), uniqm); 1685 return wf.find_witness_definer(ctxk, changes); 1686} 1687 1688// Find the set of all non-abstract methods under ctxk that match m. 1689// (The method m must be defined or inherited in ctxk.) 1690// Include m itself in the set, unless it is abstract. 1691// If this set has exactly one element, return that element. 1692Method* Dependencies::find_unique_concrete_method(Klass* ctxk, Method* m) { 1693 // Return NULL if m is marked old; must have been a redefined method. 1694 if (m->is_old()) { 1695 return NULL; 1696 } 1697 ClassHierarchyWalker wf(m); 1698 assert(wf.check_method_context(ctxk, m), "proper context"); 1699 wf.record_witnesses(1); 1700 Klass* wit = wf.find_witness_definer(ctxk); 1701 if (wit != NULL) return NULL; // Too many witnesses. 1702 Method* fm = wf.found_method(0); // Will be NULL if num_parts == 0. 1703 if (Dependencies::is_concrete_method(m, ctxk)) { 1704 if (fm == NULL) { 1705 // It turns out that m was always the only implementation. 1706 fm = m; 1707 } else if (fm != m) { 1708 // Two conflicting implementations after all. 1709 // (This can happen if m is inherited into ctxk and fm overrides it.) 1710 return NULL; 1711 } 1712 } 1713#ifndef PRODUCT 1714 // Make sure the dependency mechanism will pass this discovery: 1715 if (VerifyDependencies && fm != NULL) { 1716 guarantee(NULL == (void *)check_unique_concrete_method(ctxk, fm), 1717 "verify dep."); 1718 } 1719#endif //PRODUCT 1720 return fm; 1721} 1722 1723Klass* Dependencies::check_exclusive_concrete_methods(Klass* ctxk, 1724 Method* m1, 1725 Method* m2, 1726 KlassDepChange* changes) { 1727 ClassHierarchyWalker wf(m1); 1728 wf.add_participant(m1->method_holder()); 1729 wf.add_participant(m2->method_holder()); 1730 return wf.find_witness_definer(ctxk, changes); 1731} 1732 1733Klass* Dependencies::check_has_no_finalizable_subclasses(Klass* ctxk, KlassDepChange* changes) { 1734 Klass* search_at = ctxk; 1735 if (changes != NULL) 1736 search_at = changes->new_type(); // just look at the new bit 1737 return find_finalizable_subclass(search_at); 1738} 1739 1740Klass* Dependencies::check_call_site_target_value(oop call_site, oop method_handle, CallSiteDepChange* changes) { 1741 assert(!oopDesc::is_null(call_site), "sanity"); 1742 assert(!oopDesc::is_null(method_handle), "sanity"); 1743 assert(call_site->is_a(SystemDictionary::CallSite_klass()), "sanity"); 1744 1745 if (changes == NULL) { 1746 // Validate all CallSites 1747 if (java_lang_invoke_CallSite::target(call_site) != method_handle) 1748 return call_site->klass(); // assertion failed 1749 } else { 1750 // Validate the given CallSite 1751 if (call_site == changes->call_site() && java_lang_invoke_CallSite::target(call_site) != changes->method_handle()) { 1752 assert(method_handle != changes->method_handle(), "must be"); 1753 return call_site->klass(); // assertion failed 1754 } 1755 } 1756 return NULL; // assertion still valid 1757} 1758 1759void Dependencies::DepStream::trace_and_log_witness(Klass* witness) { 1760 if (witness != NULL) { 1761 if (TraceDependencies) { 1762 print_dependency(witness, /*verbose=*/ true); 1763 } 1764 // The following is a no-op unless logging is enabled: 1765 log_dependency(witness); 1766 } 1767} 1768 1769 1770Klass* Dependencies::DepStream::check_klass_dependency(KlassDepChange* changes) { 1771 assert_locked_or_safepoint(Compile_lock); 1772 Dependencies::check_valid_dependency_type(type()); 1773 1774 Klass* witness = NULL; 1775 switch (type()) { 1776 case evol_method: 1777 witness = check_evol_method(method_argument(0)); 1778 break; 1779 case leaf_type: 1780 witness = check_leaf_type(context_type()); 1781 break; 1782 case abstract_with_unique_concrete_subtype: 1783 witness = check_abstract_with_unique_concrete_subtype(context_type(), type_argument(1), changes); 1784 break; 1785 case abstract_with_no_concrete_subtype: 1786 witness = check_abstract_with_no_concrete_subtype(context_type(), changes); 1787 break; 1788 case concrete_with_no_concrete_subtype: 1789 witness = check_concrete_with_no_concrete_subtype(context_type(), changes); 1790 break; 1791 case unique_concrete_method: 1792 witness = check_unique_concrete_method(context_type(), method_argument(1), changes); 1793 break; 1794 case abstract_with_exclusive_concrete_subtypes_2: 1795 witness = check_abstract_with_exclusive_concrete_subtypes(context_type(), type_argument(1), type_argument(2), changes); 1796 break; 1797 case exclusive_concrete_methods_2: 1798 witness = check_exclusive_concrete_methods(context_type(), method_argument(1), method_argument(2), changes); 1799 break; 1800 case no_finalizable_subclasses: 1801 witness = check_has_no_finalizable_subclasses(context_type(), changes); 1802 break; 1803 default: 1804 witness = NULL; 1805 break; 1806 } 1807 trace_and_log_witness(witness); 1808 return witness; 1809} 1810 1811 1812Klass* Dependencies::DepStream::check_call_site_dependency(CallSiteDepChange* changes) { 1813 assert_locked_or_safepoint(Compile_lock); 1814 Dependencies::check_valid_dependency_type(type()); 1815 1816 Klass* witness = NULL; 1817 switch (type()) { 1818 case call_site_target_value: 1819 witness = check_call_site_target_value(argument_oop(0), argument_oop(1), changes); 1820 break; 1821 default: 1822 witness = NULL; 1823 break; 1824 } 1825 trace_and_log_witness(witness); 1826 return witness; 1827} 1828 1829 1830Klass* Dependencies::DepStream::spot_check_dependency_at(DepChange& changes) { 1831 // Handle klass dependency 1832 if (changes.is_klass_change() && changes.as_klass_change()->involves_context(context_type())) 1833 return check_klass_dependency(changes.as_klass_change()); 1834 1835 // Handle CallSite dependency 1836 if (changes.is_call_site_change()) 1837 return check_call_site_dependency(changes.as_call_site_change()); 1838 1839 // irrelevant dependency; skip it 1840 return NULL; 1841} 1842 1843 1844void DepChange::print() { 1845 int nsup = 0, nint = 0; 1846 for (ContextStream str(*this); str.next(); ) { 1847 Klass* k = str.klass(); 1848 switch (str.change_type()) { 1849 case Change_new_type: 1850 tty->print_cr(" dependee = %s", k->external_name()); 1851 break; 1852 case Change_new_sub: 1853 if (!WizardMode) { 1854 ++nsup; 1855 } else { 1856 tty->print_cr(" context super = %s", k->external_name()); 1857 } 1858 break; 1859 case Change_new_impl: 1860 if (!WizardMode) { 1861 ++nint; 1862 } else { 1863 tty->print_cr(" context interface = %s", k->external_name()); 1864 } 1865 break; 1866 } 1867 } 1868 if (nsup + nint != 0) { 1869 tty->print_cr(" context supers = %d, interfaces = %d", nsup, nint); 1870 } 1871} 1872 1873void DepChange::ContextStream::start() { 1874 Klass* new_type = _changes.is_klass_change() ? _changes.as_klass_change()->new_type() : (Klass*) NULL; 1875 _change_type = (new_type == NULL ? NO_CHANGE : Start_Klass); 1876 _klass = new_type; 1877 _ti_base = NULL; 1878 _ti_index = 0; 1879 _ti_limit = 0; 1880} 1881 1882bool DepChange::ContextStream::next() { 1883 switch (_change_type) { 1884 case Start_Klass: // initial state; _klass is the new type 1885 _ti_base = InstanceKlass::cast(_klass)->transitive_interfaces(); 1886 _ti_index = 0; 1887 _change_type = Change_new_type; 1888 return true; 1889 case Change_new_type: 1890 // fall through: 1891 _change_type = Change_new_sub; 1892 case Change_new_sub: 1893 // 6598190: brackets workaround Sun Studio C++ compiler bug 6629277 1894 { 1895 _klass = _klass->super(); 1896 if (_klass != NULL) { 1897 return true; 1898 } 1899 } 1900 // else set up _ti_limit and fall through: 1901 _ti_limit = (_ti_base == NULL) ? 0 : _ti_base->length(); 1902 _change_type = Change_new_impl; 1903 case Change_new_impl: 1904 if (_ti_index < _ti_limit) { 1905 _klass = _ti_base->at(_ti_index++); 1906 return true; 1907 } 1908 // fall through: 1909 _change_type = NO_CHANGE; // iterator is exhausted 1910 case NO_CHANGE: 1911 break; 1912 default: 1913 ShouldNotReachHere(); 1914 } 1915 return false; 1916} 1917 1918void KlassDepChange::initialize() { 1919 // entire transaction must be under this lock: 1920 assert_lock_strong(Compile_lock); 1921 1922 // Mark all dependee and all its superclasses 1923 // Mark transitive interfaces 1924 for (ContextStream str(*this); str.next(); ) { 1925 Klass* d = str.klass(); 1926 assert(!InstanceKlass::cast(d)->is_marked_dependent(), "checking"); 1927 InstanceKlass::cast(d)->set_is_marked_dependent(true); 1928 } 1929} 1930 1931KlassDepChange::~KlassDepChange() { 1932 // Unmark all dependee and all its superclasses 1933 // Unmark transitive interfaces 1934 for (ContextStream str(*this); str.next(); ) { 1935 Klass* d = str.klass(); 1936 InstanceKlass::cast(d)->set_is_marked_dependent(false); 1937 } 1938} 1939 1940bool KlassDepChange::involves_context(Klass* k) { 1941 if (k == NULL || !k->is_instance_klass()) { 1942 return false; 1943 } 1944 InstanceKlass* ik = InstanceKlass::cast(k); 1945 bool is_contained = ik->is_marked_dependent(); 1946 assert(is_contained == new_type()->is_subtype_of(k), 1947 "correct marking of potential context types"); 1948 return is_contained; 1949} 1950 1951#ifndef PRODUCT 1952void Dependencies::print_statistics() { 1953 if (deps_find_witness_print != 0) { 1954 // Call one final time, to flush out the data. 1955 deps_find_witness_print = -1; 1956 count_find_witness_calls(); 1957 } 1958} 1959#endif 1960 1961CallSiteDepChange::CallSiteDepChange(Handle call_site, Handle method_handle) : 1962 _call_site(call_site), 1963 _method_handle(method_handle) { 1964 assert(_call_site()->is_a(SystemDictionary::CallSite_klass()), "must be"); 1965 assert(_method_handle.is_null() || _method_handle()->is_a(SystemDictionary::MethodHandle_klass()), "must be"); 1966} 1967