1 /* 2 * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "ci/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 43 static 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 52 void 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 70 void Dependencies::assert_evol_method(ciMethod* m) { 71 assert_common_1(evol_method, m); 72 } 73 74 void 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 89 void 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 94 void 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 99 void 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 } 103 104 void Dependencies::assert_unique_concrete_method(ciKlass* ctxk, ciMethod* uniqm) { 105 check_ctxk(ctxk); 106 assert_common_2(unique_concrete_method, ctxk, uniqm); 107 } 108 109 void 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 } 113 114 void 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 } 118 119 void Dependencies::assert_has_no_finalizable_subclasses(ciKlass* ctxk) { 120 check_ctxk(ctxk); 121 assert_common_1(no_finalizable_subclasses, ctxk); 122 } 123 124 void 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 129 130 Dependencies::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 } 144 145 void Dependencies::assert_evol_method(Method* m) { 146 assert_common_1(evol_method, DepValue(_oop_recorder, m)); 147 } 148 149 void Dependencies::assert_has_no_finalizable_subclasses(Klass* ctxk) { 150 check_ctxk(ctxk); 151 assert_common_1(no_finalizable_subclasses, DepValue(_oop_recorder, ctxk)); 152 } 153 154 void 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 } 168 169 void 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 } 175 176 void 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 } 180 181 void 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 // 191 bool 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 } 204 205 void 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 } 217 218 void 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 } 258 259 void 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 default: 276 break; 277 } 278 if (swap) { ciBaseObject* t = x; x = x2; x2 = t; } 279 280 // see if the same (or a similar) dep is already recorded 281 if (note_dep_seen(dept, x) && note_dep_seen(dept, x2)) { 282 // look in this bucket for redundant assertions 283 const int stride = 3; 284 for (int i = deps->length(); (i -= stride) >= 0; ) { 285 ciBaseObject* y = deps->at(i+1); 286 ciBaseObject* y2 = deps->at(i+2); 287 if (x == y && x2 == y2) { // same subjects; check the context 288 if (maybe_merge_ctxk(deps, i+0, ctxk)) { 289 return; 290 } 291 } 292 } 293 } 294 // append the assertion in the correct bucket: 295 deps->append(ctxk); 296 deps->append(x); 297 deps->append(x2); 298 } 299 300 #if INCLUDE_JVMCI 301 bool Dependencies::maybe_merge_ctxk(GrowableArray<DepValue>* deps, 302 int ctxk_i, DepValue ctxk2_dv) { 303 Klass* ctxk1 = deps->at(ctxk_i).as_klass(_oop_recorder); 304 Klass* ctxk2 = ctxk2_dv.as_klass(_oop_recorder); 305 if (ctxk2->is_subtype_of(ctxk1)) { 306 return true; // success, and no need to change 307 } else if (ctxk1->is_subtype_of(ctxk2)) { 308 // new context class fully subsumes previous one 309 deps->at_put(ctxk_i, ctxk2_dv); 310 return true; 311 } else { 312 return false; 313 } 314 } 315 316 void Dependencies::assert_common_1(DepType dept, DepValue x) { 317 assert(dep_args(dept) == 1, "sanity"); 318 //log_dependency(dept, x); 319 GrowableArray<DepValue>* deps = _dep_values[dept]; 320 321 // see if the same (or a similar) dep is already recorded 322 if (note_dep_seen(dept, x)) { 323 assert(deps->find(x) >= 0, "sanity"); 324 } else { 325 deps->append(x); 326 } 327 } 328 329 void Dependencies::assert_common_2(DepType dept, 330 DepValue x0, DepValue x1) { 331 assert(dep_args(dept) == 2, "sanity"); 332 //log_dependency(dept, x0, x1); 333 GrowableArray<DepValue>* deps = _dep_values[dept]; 334 335 // see if the same (or a similar) dep is already recorded 336 bool has_ctxk = has_explicit_context_arg(dept); 337 if (has_ctxk) { 338 assert(dep_context_arg(dept) == 0, "sanity"); 339 if (note_dep_seen(dept, x1)) { 340 // look in this bucket for redundant assertions 341 const int stride = 2; 342 for (int i = deps->length(); (i -= stride) >= 0; ) { 343 DepValue y1 = deps->at(i+1); 344 if (x1 == y1) { // same subject; check the context 345 if (maybe_merge_ctxk(deps, i+0, x0)) { 346 return; 347 } 348 } 349 } 350 } 351 } else { 352 if (note_dep_seen(dept, x0) && note_dep_seen(dept, x1)) { 353 // look in this bucket for redundant assertions 354 const int stride = 2; 355 for (int i = deps->length(); (i -= stride) >= 0; ) { 356 DepValue y0 = deps->at(i+0); 357 DepValue y1 = deps->at(i+1); 358 if (x0 == y0 && x1 == y1) { 359 return; 360 } 361 } 362 } 363 } 364 365 // append the assertion in the correct bucket: 366 deps->append(x0); 367 deps->append(x1); 368 } 369 #endif // INCLUDE_JVMCI 370 371 /// Support for encoding dependencies into an nmethod: 372 373 void Dependencies::copy_to(nmethod* nm) { 374 address beg = nm->dependencies_begin(); 375 address end = nm->dependencies_end(); 376 guarantee(end - beg >= (ptrdiff_t) size_in_bytes(), "bad sizing"); 377 Copy::disjoint_words((HeapWord*) content_bytes(), 378 (HeapWord*) beg, 379 size_in_bytes() / sizeof(HeapWord)); 380 assert(size_in_bytes() % sizeof(HeapWord) == 0, "copy by words"); 381 } 382 383 static int sort_dep(ciBaseObject** p1, ciBaseObject** p2, int narg) { 384 for (int i = 0; i < narg; i++) { 385 int diff = p1[i]->ident() - p2[i]->ident(); 386 if (diff != 0) return diff; 387 } 388 return 0; 389 } 390 static int sort_dep_arg_1(ciBaseObject** p1, ciBaseObject** p2) 391 { return sort_dep(p1, p2, 1); } 392 static int sort_dep_arg_2(ciBaseObject** p1, ciBaseObject** p2) 393 { return sort_dep(p1, p2, 2); } 394 static int sort_dep_arg_3(ciBaseObject** p1, ciBaseObject** p2) 395 { return sort_dep(p1, p2, 3); } 396 397 #if INCLUDE_JVMCI 398 // metadata deps are sorted before object deps 399 static int sort_dep_value(Dependencies::DepValue* p1, Dependencies::DepValue* p2, int narg) { 400 for (int i = 0; i < narg; i++) { 401 int diff = p1[i].sort_key() - p2[i].sort_key(); 402 if (diff != 0) return diff; 403 } 404 return 0; 405 } 406 static int sort_dep_value_arg_1(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 407 { return sort_dep_value(p1, p2, 1); } 408 static int sort_dep_value_arg_2(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 409 { return sort_dep_value(p1, p2, 2); } 410 static int sort_dep_value_arg_3(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 411 { return sort_dep_value(p1, p2, 3); } 412 #endif // INCLUDE_JVMCI 413 414 void Dependencies::sort_all_deps() { 415 #if INCLUDE_JVMCI 416 if (_using_dep_values) { 417 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 418 DepType dept = (DepType)deptv; 419 GrowableArray<DepValue>* deps = _dep_values[dept]; 420 if (deps->length() <= 1) continue; 421 switch (dep_args(dept)) { 422 case 1: deps->sort(sort_dep_value_arg_1, 1); break; 423 case 2: deps->sort(sort_dep_value_arg_2, 2); break; 424 case 3: deps->sort(sort_dep_value_arg_3, 3); break; 425 default: ShouldNotReachHere(); break; 426 } 427 } 428 return; 429 } 430 #endif // INCLUDE_JVMCI 431 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 432 DepType dept = (DepType)deptv; 433 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 434 if (deps->length() <= 1) continue; 435 switch (dep_args(dept)) { 436 case 1: deps->sort(sort_dep_arg_1, 1); break; 437 case 2: deps->sort(sort_dep_arg_2, 2); break; 438 case 3: deps->sort(sort_dep_arg_3, 3); break; 439 default: ShouldNotReachHere(); break; 440 } 441 } 442 } 443 444 size_t Dependencies::estimate_size_in_bytes() { 445 size_t est_size = 100; 446 #if INCLUDE_JVMCI 447 if (_using_dep_values) { 448 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 449 DepType dept = (DepType)deptv; 450 GrowableArray<DepValue>* deps = _dep_values[dept]; 451 est_size += deps->length() * 2; // tags and argument(s) 452 } 453 return est_size; 454 } 455 #endif // INCLUDE_JVMCI 456 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 457 DepType dept = (DepType)deptv; 458 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 459 est_size += deps->length()*2; // tags and argument(s) 460 } 461 return est_size; 462 } 463 464 ciKlass* Dependencies::ctxk_encoded_as_null(DepType dept, ciBaseObject* x) { 465 switch (dept) { 466 case abstract_with_exclusive_concrete_subtypes_2: 467 return x->as_metadata()->as_klass(); 468 case unique_concrete_method: 469 case exclusive_concrete_methods_2: 470 return x->as_metadata()->as_method()->holder(); 471 default: 472 return NULL; // let NULL be NULL 473 } 474 } 475 476 Klass* Dependencies::ctxk_encoded_as_null(DepType dept, Metadata* x) { 477 assert(must_be_in_vm(), "raw oops here"); 478 switch (dept) { 479 case abstract_with_exclusive_concrete_subtypes_2: 480 assert(x->is_klass(), "sanity"); 481 return (Klass*) x; 482 case unique_concrete_method: 483 case exclusive_concrete_methods_2: 484 assert(x->is_method(), "sanity"); 485 return ((Method*)x)->method_holder(); 486 default: 487 return NULL; // let NULL be NULL 488 } 489 } 490 491 void Dependencies::encode_content_bytes() { 492 sort_all_deps(); 493 494 // cast is safe, no deps can overflow INT_MAX 495 CompressedWriteStream bytes((int)estimate_size_in_bytes()); 496 497 #if INCLUDE_JVMCI 498 if (_using_dep_values) { 499 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 500 DepType dept = (DepType)deptv; 501 GrowableArray<DepValue>* deps = _dep_values[dept]; 502 if (deps->length() == 0) continue; 503 int stride = dep_args(dept); 504 int ctxkj = dep_context_arg(dept); // -1 if no context arg 505 assert(stride > 0, "sanity"); 506 for (int i = 0; i < deps->length(); i += stride) { 507 jbyte code_byte = (jbyte)dept; 508 int skipj = -1; 509 if (ctxkj >= 0 && ctxkj+1 < stride) { 510 Klass* ctxk = deps->at(i+ctxkj+0).as_klass(_oop_recorder); 511 DepValue x = deps->at(i+ctxkj+1); // following argument 512 if (ctxk == ctxk_encoded_as_null(dept, x.as_metadata(_oop_recorder))) { 513 skipj = ctxkj; // we win: maybe one less oop to keep track of 514 code_byte |= default_context_type_bit; 515 } 516 } 517 bytes.write_byte(code_byte); 518 for (int j = 0; j < stride; j++) { 519 if (j == skipj) continue; 520 DepValue v = deps->at(i+j); 521 int idx = v.index(); 522 bytes.write_int(idx); 523 } 524 } 525 } 526 } else { 527 #endif // INCLUDE_JVMCI 528 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 529 DepType dept = (DepType)deptv; 530 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 531 if (deps->length() == 0) continue; 532 int stride = dep_args(dept); 533 int ctxkj = dep_context_arg(dept); // -1 if no context arg 534 assert(stride > 0, "sanity"); 535 for (int i = 0; i < deps->length(); i += stride) { 536 jbyte code_byte = (jbyte)dept; 537 int skipj = -1; 538 if (ctxkj >= 0 && ctxkj+1 < stride) { 539 ciKlass* ctxk = deps->at(i+ctxkj+0)->as_metadata()->as_klass(); 540 ciBaseObject* x = deps->at(i+ctxkj+1); // following argument 541 if (ctxk == ctxk_encoded_as_null(dept, x)) { 542 skipj = ctxkj; // we win: maybe one less oop to keep track of 543 code_byte |= default_context_type_bit; 544 } 545 } 546 bytes.write_byte(code_byte); 547 for (int j = 0; j < stride; j++) { 548 if (j == skipj) continue; 549 ciBaseObject* v = deps->at(i+j); 550 int idx; 551 if (v->is_object()) { 552 idx = _oop_recorder->find_index(v->as_object()->constant_encoding()); 553 } else { 554 ciMetadata* meta = v->as_metadata(); 555 idx = _oop_recorder->find_index(meta->constant_encoding()); 556 } 557 bytes.write_int(idx); 558 } 559 } 560 } 561 #if INCLUDE_JVMCI 562 } 563 #endif 564 565 // write a sentinel byte to mark the end 566 bytes.write_byte(end_marker); 567 568 // round it out to a word boundary 569 while (bytes.position() % sizeof(HeapWord) != 0) { 570 bytes.write_byte(end_marker); 571 } 572 573 // check whether the dept byte encoding really works 574 assert((jbyte)default_context_type_bit != 0, "byte overflow"); 575 576 _content_bytes = bytes.buffer(); 577 _size_in_bytes = bytes.position(); 578 } 579 580 581 const char* Dependencies::_dep_name[TYPE_LIMIT] = { 582 "end_marker", 583 "evol_method", 584 "leaf_type", 585 "abstract_with_unique_concrete_subtype", 586 "abstract_with_no_concrete_subtype", 587 "concrete_with_no_concrete_subtype", 588 "unique_concrete_method", 589 "abstract_with_exclusive_concrete_subtypes_2", 590 "exclusive_concrete_methods_2", 591 "no_finalizable_subclasses", 592 "call_site_target_value" 593 }; 594 595 int Dependencies::_dep_args[TYPE_LIMIT] = { 596 -1,// end_marker 597 1, // evol_method m 598 1, // leaf_type ctxk 599 2, // abstract_with_unique_concrete_subtype ctxk, k 600 1, // abstract_with_no_concrete_subtype ctxk 601 1, // concrete_with_no_concrete_subtype ctxk 602 2, // unique_concrete_method ctxk, m 603 3, // unique_concrete_subtypes_2 ctxk, k1, k2 604 3, // unique_concrete_methods_2 ctxk, m1, m2 605 1, // no_finalizable_subclasses ctxk 606 2 // call_site_target_value call_site, method_handle 607 }; 608 609 const char* Dependencies::dep_name(Dependencies::DepType dept) { 610 if (!dept_in_mask(dept, all_types)) return "?bad-dep?"; 611 return _dep_name[dept]; 612 } 613 614 int Dependencies::dep_args(Dependencies::DepType dept) { 615 if (!dept_in_mask(dept, all_types)) return -1; 616 return _dep_args[dept]; 617 } 618 619 void Dependencies::check_valid_dependency_type(DepType dept) { 620 guarantee(FIRST_TYPE <= dept && dept < TYPE_LIMIT, "invalid dependency type: %d", (int) dept); 621 } 622 623 // for the sake of the compiler log, print out current dependencies: 624 void Dependencies::log_all_dependencies() { 625 if (log() == NULL) return; 626 ResourceMark rm; 627 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 628 DepType dept = (DepType)deptv; 629 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 630 int deplen = deps->length(); 631 if (deplen == 0) { 632 continue; 633 } 634 int stride = dep_args(dept); 635 GrowableArray<ciBaseObject*>* ciargs = new GrowableArray<ciBaseObject*>(stride); 636 for (int i = 0; i < deps->length(); i += stride) { 637 for (int j = 0; j < stride; j++) { 638 // flush out the identities before printing 639 ciargs->push(deps->at(i+j)); 640 } 641 write_dependency_to(log(), dept, ciargs); 642 ciargs->clear(); 643 } 644 guarantee(deplen == deps->length(), "deps array cannot grow inside nested ResoureMark scope"); 645 } 646 } 647 648 void Dependencies::write_dependency_to(CompileLog* log, 649 DepType dept, 650 GrowableArray<DepArgument>* args, 651 Klass* witness) { 652 if (log == NULL) { 653 return; 654 } 655 ResourceMark rm; 656 ciEnv* env = ciEnv::current(); 657 GrowableArray<ciBaseObject*>* ciargs = new GrowableArray<ciBaseObject*>(args->length()); 658 for (GrowableArrayIterator<DepArgument> it = args->begin(); it != args->end(); ++it) { 659 DepArgument arg = *it; 660 if (arg.is_oop()) { 661 ciargs->push(env->get_object(arg.oop_value())); 662 } else { 663 ciargs->push(env->get_metadata(arg.metadata_value())); 664 } 665 } 666 int argslen = ciargs->length(); 667 Dependencies::write_dependency_to(log, dept, ciargs, witness); 668 guarantee(argslen == ciargs->length(), "ciargs array cannot grow inside nested ResoureMark scope"); 669 } 670 671 void Dependencies::write_dependency_to(CompileLog* log, 672 DepType dept, 673 GrowableArray<ciBaseObject*>* args, 674 Klass* witness) { 675 if (log == NULL) { 676 return; 677 } 678 ResourceMark rm; 679 GrowableArray<int>* argids = new GrowableArray<int>(args->length()); 680 for (GrowableArrayIterator<ciBaseObject*> it = args->begin(); it != args->end(); ++it) { 681 ciBaseObject* obj = *it; 682 if (obj->is_object()) { 683 argids->push(log->identify(obj->as_object())); 684 } else { 685 argids->push(log->identify(obj->as_metadata())); 686 } 687 } 688 if (witness != NULL) { 689 log->begin_elem("dependency_failed"); 690 } else { 691 log->begin_elem("dependency"); 692 } 693 log->print(" type='%s'", dep_name(dept)); 694 const int ctxkj = dep_context_arg(dept); // -1 if no context arg 695 if (ctxkj >= 0 && ctxkj < argids->length()) { 696 log->print(" ctxk='%d'", argids->at(ctxkj)); 697 } 698 // write remaining arguments, if any. 699 for (int j = 0; j < argids->length(); j++) { 700 if (j == ctxkj) continue; // already logged 701 if (j == 1) { 702 log->print( " x='%d'", argids->at(j)); 703 } else { 704 log->print(" x%d='%d'", j, argids->at(j)); 705 } 706 } 707 if (witness != NULL) { 708 log->object("witness", witness); 709 log->stamp(); 710 } 711 log->end_elem(); 712 } 713 714 void Dependencies::write_dependency_to(xmlStream* xtty, 715 DepType dept, 716 GrowableArray<DepArgument>* args, 717 Klass* witness) { 718 if (xtty == NULL) { 719 return; 720 } 721 Thread* thread = Thread::current(); 722 HandleMark rm(thread); 723 ttyLocker ttyl; 724 int ctxkj = dep_context_arg(dept); // -1 if no context arg 725 if (witness != NULL) { 726 xtty->begin_elem("dependency_failed"); 727 } else { 728 xtty->begin_elem("dependency"); 729 } 730 xtty->print(" type='%s'", dep_name(dept)); 731 if (ctxkj >= 0) { 732 xtty->object("ctxk", args->at(ctxkj).metadata_value()); 733 } 734 // write remaining arguments, if any. 735 for (int j = 0; j < args->length(); j++) { 736 if (j == ctxkj) continue; // already logged 737 DepArgument arg = args->at(j); 738 if (j == 1) { 739 if (arg.is_oop()) { 740 xtty->object("x", Handle(thread, arg.oop_value())); 741 } else { 742 xtty->object("x", arg.metadata_value()); 743 } 744 } else { 745 char xn[12]; sprintf(xn, "x%d", j); 746 if (arg.is_oop()) { 747 xtty->object(xn, Handle(thread, arg.oop_value())); 748 } else { 749 xtty->object(xn, arg.metadata_value()); 750 } 751 } 752 } 753 if (witness != NULL) { 754 xtty->object("witness", witness); 755 xtty->stamp(); 756 } 757 xtty->end_elem(); 758 } 759 760 void Dependencies::print_dependency(DepType dept, GrowableArray<DepArgument>* args, 761 Klass* witness, outputStream* st) { 762 ResourceMark rm; 763 ttyLocker ttyl; // keep the following output all in one block 764 st->print_cr("%s of type %s", 765 (witness == NULL)? "Dependency": "Failed dependency", 766 dep_name(dept)); 767 // print arguments 768 int ctxkj = dep_context_arg(dept); // -1 if no context arg 769 for (int j = 0; j < args->length(); j++) { 770 DepArgument arg = args->at(j); 771 bool put_star = false; 772 if (arg.is_null()) continue; 773 const char* what; 774 if (j == ctxkj) { 775 assert(arg.is_metadata(), "must be"); 776 what = "context"; 777 put_star = !Dependencies::is_concrete_klass((Klass*)arg.metadata_value()); 778 } else if (arg.is_method()) { 779 what = "method "; 780 put_star = !Dependencies::is_concrete_method((Method*)arg.metadata_value(), NULL); 781 } else if (arg.is_klass()) { 782 what = "class "; 783 } else { 784 what = "object "; 785 } 786 st->print(" %s = %s", what, (put_star? "*": "")); 787 if (arg.is_klass()) { 788 st->print("%s", ((Klass*)arg.metadata_value())->external_name()); 789 } else if (arg.is_method()) { 790 ((Method*)arg.metadata_value())->print_value_on(st); 791 } else if (arg.is_oop()) { 792 arg.oop_value()->print_value_on(st); 793 } else { 794 ShouldNotReachHere(); // Provide impl for this type. 795 } 796 797 st->cr(); 798 } 799 if (witness != NULL) { 800 bool put_star = !Dependencies::is_concrete_klass(witness); 801 st->print_cr(" witness = %s%s", 802 (put_star? "*": ""), 803 witness->external_name()); 804 } 805 } 806 807 void Dependencies::DepStream::log_dependency(Klass* witness) { 808 if (_deps == NULL && xtty == NULL) return; // fast cutout for runtime 809 ResourceMark rm; 810 const int nargs = argument_count(); 811 GrowableArray<DepArgument>* args = new GrowableArray<DepArgument>(nargs); 812 for (int j = 0; j < nargs; j++) { 813 if (is_oop_argument(j)) { 814 args->push(argument_oop(j)); 815 } else { 816 args->push(argument(j)); 817 } 818 } 819 int argslen = args->length(); 820 if (_deps != NULL && _deps->log() != NULL) { 821 if (ciEnv::current() != NULL) { 822 Dependencies::write_dependency_to(_deps->log(), type(), args, witness); 823 } else { 824 // Treat the CompileLog as an xmlstream instead 825 Dependencies::write_dependency_to((xmlStream*)_deps->log(), type(), args, witness); 826 } 827 } else { 828 Dependencies::write_dependency_to(xtty, type(), args, witness); 829 } 830 guarantee(argslen == args->length(), "args array cannot grow inside nested ResoureMark scope"); 831 } 832 833 void Dependencies::DepStream::print_dependency(Klass* witness, bool verbose, outputStream* st) { 834 ResourceMark rm; 835 int nargs = argument_count(); 836 GrowableArray<DepArgument>* args = new GrowableArray<DepArgument>(nargs); 837 for (int j = 0; j < nargs; j++) { 838 if (is_oop_argument(j)) { 839 args->push(argument_oop(j)); 840 } else { 841 args->push(argument(j)); 842 } 843 } 844 int argslen = args->length(); 845 Dependencies::print_dependency(type(), args, witness, st); 846 if (verbose) { 847 if (_code != NULL) { 848 st->print(" code: "); 849 _code->print_value_on(st); 850 st->cr(); 851 } 852 } 853 guarantee(argslen == args->length(), "args array cannot grow inside nested ResoureMark scope"); 854 } 855 856 857 /// Dependency stream support (decodes dependencies from an nmethod): 858 859 #ifdef ASSERT 860 void Dependencies::DepStream::initial_asserts(size_t byte_limit) { 861 assert(must_be_in_vm(), "raw oops here"); 862 _byte_limit = byte_limit; 863 _type = (DepType)(end_marker-1); // defeat "already at end" assert 864 assert((_code!=NULL) + (_deps!=NULL) == 1, "one or t'other"); 865 } 866 #endif //ASSERT 867 868 bool Dependencies::DepStream::next() { 869 assert(_type != end_marker, "already at end"); 870 if (_bytes.position() == 0 && _code != NULL 871 && _code->dependencies_size() == 0) { 872 // Method has no dependencies at all. 873 return false; 874 } 875 int code_byte = (_bytes.read_byte() & 0xFF); 876 if (code_byte == end_marker) { 877 DEBUG_ONLY(_type = end_marker); 878 return false; 879 } else { 880 int ctxk_bit = (code_byte & Dependencies::default_context_type_bit); 881 code_byte -= ctxk_bit; 882 DepType dept = (DepType)code_byte; 883 _type = dept; 884 Dependencies::check_valid_dependency_type(dept); 885 int stride = _dep_args[dept]; 886 assert(stride == dep_args(dept), "sanity"); 887 int skipj = -1; 888 if (ctxk_bit != 0) { 889 skipj = 0; // currently the only context argument is at zero 890 assert(skipj == dep_context_arg(dept), "zero arg always ctxk"); 891 } 892 for (int j = 0; j < stride; j++) { 893 _xi[j] = (j == skipj)? 0: _bytes.read_int(); 894 } 895 DEBUG_ONLY(_xi[stride] = -1); // help detect overruns 896 return true; 897 } 898 } 899 900 inline Metadata* Dependencies::DepStream::recorded_metadata_at(int i) { 901 Metadata* o = NULL; 902 if (_code != NULL) { 903 o = _code->metadata_at(i); 904 } else { 905 o = _deps->oop_recorder()->metadata_at(i); 906 } 907 return o; 908 } 909 910 inline oop Dependencies::DepStream::recorded_oop_at(int i) { 911 return (_code != NULL) 912 ? _code->oop_at(i) 913 : JNIHandles::resolve(_deps->oop_recorder()->oop_at(i)); 914 } 915 916 Metadata* Dependencies::DepStream::argument(int i) { 917 Metadata* result = recorded_metadata_at(argument_index(i)); 918 919 if (result == NULL) { // Explicit context argument can be compressed 920 int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg 921 if (ctxkj >= 0 && i == ctxkj && ctxkj+1 < argument_count()) { 922 result = ctxk_encoded_as_null(type(), argument(ctxkj+1)); 923 } 924 } 925 926 assert(result == NULL || result->is_klass() || result->is_method(), "must be"); 927 return result; 928 } 929 930 /** 931 * Returns a unique identifier for each dependency argument. 932 */ 933 uintptr_t Dependencies::DepStream::get_identifier(int i) { 934 if (is_oop_argument(i)) { 935 return (uintptr_t)(oopDesc*)argument_oop(i); 936 } else { 937 return (uintptr_t)argument(i); 938 } 939 } 940 941 oop Dependencies::DepStream::argument_oop(int i) { 942 oop result = recorded_oop_at(argument_index(i)); 943 assert(result == NULL || oopDesc::is_oop(result), "must be"); 944 return result; 945 } 946 947 Klass* Dependencies::DepStream::context_type() { 948 assert(must_be_in_vm(), "raw oops here"); 949 950 // Most dependencies have an explicit context type argument. 951 { 952 int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg 953 if (ctxkj >= 0) { 954 Metadata* k = argument(ctxkj); 955 assert(k != NULL && k->is_klass(), "type check"); 956 return (Klass*)k; 957 } 958 } 959 960 // Some dependencies are using the klass of the first object 961 // argument as implicit context type. 962 { 963 int ctxkj = dep_implicit_context_arg(type()); 964 if (ctxkj >= 0) { 965 Klass* k = argument_oop(ctxkj)->klass(); 966 assert(k != NULL && k->is_klass(), "type check"); 967 return (Klass*) k; 968 } 969 } 970 971 // And some dependencies don't have a context type at all, 972 // e.g. evol_method. 973 return NULL; 974 } 975 976 // ----------------- DependencySignature -------------------------------------- 977 bool DependencySignature::equals(DependencySignature const& s1, DependencySignature const& s2) { 978 if ((s1.type() != s2.type()) || (s1.args_count() != s2.args_count())) { 979 return false; 980 } 981 982 for (int i = 0; i < s1.args_count(); i++) { 983 if (s1.arg(i) != s2.arg(i)) { 984 return false; 985 } 986 } 987 return true; 988 } 989 990 /// Checking dependencies: 991 992 // This hierarchy walker inspects subtypes of a given type, 993 // trying to find a "bad" class which breaks a dependency. 994 // Such a class is called a "witness" to the broken dependency. 995 // While searching around, we ignore "participants", which 996 // are already known to the dependency. 997 class ClassHierarchyWalker { 998 public: 999 enum { PARTICIPANT_LIMIT = 3 }; 1000 1001 private: 1002 // optional method descriptor to check for: 1003 Symbol* _name; 1004 Symbol* _signature; 1005 1006 // special classes which are not allowed to be witnesses: 1007 Klass* _participants[PARTICIPANT_LIMIT+1]; 1008 int _num_participants; 1009 1010 // cache of method lookups 1011 Method* _found_methods[PARTICIPANT_LIMIT+1]; 1012 1013 // if non-zero, tells how many witnesses to convert to participants 1014 int _record_witnesses; 1015 1016 void initialize(Klass* participant) { 1017 _record_witnesses = 0; 1018 _participants[0] = participant; 1019 _found_methods[0] = NULL; 1020 _num_participants = 0; 1021 if (participant != NULL) { 1022 // Terminating NULL. 1023 _participants[1] = NULL; 1024 _found_methods[1] = NULL; 1025 _num_participants = 1; 1026 } 1027 } 1028 1029 void initialize_from_method(Method* m) { 1030 assert(m != NULL && m->is_method(), "sanity"); 1031 _name = m->name(); 1032 _signature = m->signature(); 1033 } 1034 1035 public: 1036 // The walker is initialized to recognize certain methods and/or types 1037 // as friendly participants. 1038 ClassHierarchyWalker(Klass* participant, Method* m) { 1039 initialize_from_method(m); 1040 initialize(participant); 1041 } 1042 ClassHierarchyWalker(Method* m) { 1043 initialize_from_method(m); 1044 initialize(NULL); 1045 } 1046 ClassHierarchyWalker(Klass* participant = NULL) { 1047 _name = NULL; 1048 _signature = NULL; 1049 initialize(participant); 1050 } 1051 1052 // This is common code for two searches: One for concrete subtypes, 1053 // the other for concrete method implementations and overrides. 1054 bool doing_subtype_search() { 1055 return _name == NULL; 1056 } 1057 1058 int num_participants() { return _num_participants; } 1059 Klass* participant(int n) { 1060 assert((uint)n <= (uint)_num_participants, "oob"); 1061 return _participants[n]; 1062 } 1063 1064 // Note: If n==num_participants, returns NULL. 1065 Method* found_method(int n) { 1066 assert((uint)n <= (uint)_num_participants, "oob"); 1067 Method* fm = _found_methods[n]; 1068 assert(n == _num_participants || fm != NULL, "proper usage"); 1069 if (fm != NULL && fm->method_holder() != _participants[n]) { 1070 // Default methods from interfaces can be added to classes. In 1071 // that case the holder of the method is not the class but the 1072 // interface where it's defined. 1073 assert(fm->is_default_method(), "sanity"); 1074 return NULL; 1075 } 1076 return fm; 1077 } 1078 1079 #ifdef ASSERT 1080 // Assert that m is inherited into ctxk, without intervening overrides. 1081 // (May return true even if this is not true, in corner cases where we punt.) 1082 bool check_method_context(Klass* ctxk, Method* m) { 1083 if (m->method_holder() == ctxk) 1084 return true; // Quick win. 1085 if (m->is_private()) 1086 return false; // Quick lose. Should not happen. 1087 if (!(m->is_public() || m->is_protected())) 1088 // The override story is complex when packages get involved. 1089 return true; // Must punt the assertion to true. 1090 Method* lm = ctxk->lookup_method(m->name(), m->signature()); 1091 if (lm == NULL && ctxk->is_instance_klass()) { 1092 // It might be an interface method 1093 lm = InstanceKlass::cast(ctxk)->lookup_method_in_ordered_interfaces(m->name(), 1094 m->signature()); 1095 } 1096 if (lm == m) 1097 // Method m is inherited into ctxk. 1098 return true; 1099 if (lm != NULL) { 1100 if (!(lm->is_public() || lm->is_protected())) { 1101 // Method is [package-]private, so the override story is complex. 1102 return true; // Must punt the assertion to true. 1103 } 1104 if (lm->is_static()) { 1105 // Static methods don't override non-static so punt 1106 return true; 1107 } 1108 if (!Dependencies::is_concrete_method(lm, ctxk) && 1109 !Dependencies::is_concrete_method(m, ctxk)) { 1110 // They are both non-concrete 1111 if (lm->method_holder()->is_subtype_of(m->method_holder())) { 1112 // Method m is overridden by lm, but both are non-concrete. 1113 return true; 1114 } 1115 if (lm->method_holder()->is_interface() && m->method_holder()->is_interface() && 1116 ctxk->is_subtype_of(m->method_holder()) && ctxk->is_subtype_of(lm->method_holder())) { 1117 // Interface method defined in multiple super interfaces 1118 return true; 1119 } 1120 } 1121 } 1122 ResourceMark rm; 1123 tty->print_cr("Dependency method not found in the associated context:"); 1124 tty->print_cr(" context = %s", ctxk->external_name()); 1125 tty->print( " method = "); m->print_short_name(tty); tty->cr(); 1126 if (lm != NULL) { 1127 tty->print( " found = "); lm->print_short_name(tty); tty->cr(); 1128 } 1129 return false; 1130 } 1131 #endif 1132 1133 void add_participant(Klass* participant) { 1134 assert(_num_participants + _record_witnesses < PARTICIPANT_LIMIT, "oob"); 1135 int np = _num_participants++; 1136 _participants[np] = participant; 1137 _participants[np+1] = NULL; 1138 _found_methods[np+1] = NULL; 1139 } 1140 1141 void record_witnesses(int add) { 1142 if (add > PARTICIPANT_LIMIT) add = PARTICIPANT_LIMIT; 1143 assert(_num_participants + add < PARTICIPANT_LIMIT, "oob"); 1144 _record_witnesses = add; 1145 } 1146 1147 bool is_witness(Klass* k) { 1148 if (doing_subtype_search()) { 1149 return Dependencies::is_concrete_klass(k); 1150 } else if (!k->is_instance_klass()) { 1151 return false; // no methods to find in an array type 1152 } else { 1153 // Search class hierarchy first. 1154 Method* m = InstanceKlass::cast(k)->find_instance_method(_name, _signature); 1155 if (!Dependencies::is_concrete_method(m, k)) { 1156 // Check interface defaults also, if any exist. 1157 Array<Method*>* default_methods = InstanceKlass::cast(k)->default_methods(); 1158 if (default_methods == NULL) 1159 return false; 1160 m = InstanceKlass::cast(k)->find_method(default_methods, _name, _signature); 1161 if (!Dependencies::is_concrete_method(m, NULL)) 1162 return false; 1163 } 1164 _found_methods[_num_participants] = m; 1165 // Note: If add_participant(k) is called, 1166 // the method m will already be memoized for it. 1167 return true; 1168 } 1169 } 1170 1171 bool is_participant(Klass* k) { 1172 if (k == _participants[0]) { 1173 return true; 1174 } else if (_num_participants <= 1) { 1175 return false; 1176 } else { 1177 return in_list(k, &_participants[1]); 1178 } 1179 } 1180 bool ignore_witness(Klass* witness) { 1181 if (_record_witnesses == 0) { 1182 return false; 1183 } else { 1184 --_record_witnesses; 1185 add_participant(witness); 1186 return true; 1187 } 1188 } 1189 static bool in_list(Klass* x, Klass** list) { 1190 for (int i = 0; ; i++) { 1191 Klass* y = list[i]; 1192 if (y == NULL) break; 1193 if (y == x) return true; 1194 } 1195 return false; // not in list 1196 } 1197 1198 private: 1199 // the actual search method: 1200 Klass* find_witness_anywhere(Klass* context_type, 1201 bool participants_hide_witnesses, 1202 bool top_level_call = true); 1203 // the spot-checking version: 1204 Klass* find_witness_in(KlassDepChange& changes, 1205 Klass* context_type, 1206 bool participants_hide_witnesses); 1207 public: 1208 Klass* find_witness_subtype(Klass* context_type, KlassDepChange* changes = NULL) { 1209 assert(doing_subtype_search(), "must set up a subtype search"); 1210 // When looking for unexpected concrete types, 1211 // do not look beneath expected ones. 1212 const bool participants_hide_witnesses = true; 1213 // CX > CC > C' is OK, even if C' is new. 1214 // CX > { CC, C' } is not OK if C' is new, and C' is the witness. 1215 if (changes != NULL) { 1216 return find_witness_in(*changes, context_type, participants_hide_witnesses); 1217 } else { 1218 return find_witness_anywhere(context_type, participants_hide_witnesses); 1219 } 1220 } 1221 Klass* find_witness_definer(Klass* context_type, KlassDepChange* changes = NULL) { 1222 assert(!doing_subtype_search(), "must set up a method definer search"); 1223 // When looking for unexpected concrete methods, 1224 // look beneath expected ones, to see if there are overrides. 1225 const bool participants_hide_witnesses = true; 1226 // CX.m > CC.m > C'.m is not OK, if C'.m is new, and C' is the witness. 1227 if (changes != NULL) { 1228 return find_witness_in(*changes, context_type, !participants_hide_witnesses); 1229 } else { 1230 return find_witness_anywhere(context_type, !participants_hide_witnesses); 1231 } 1232 } 1233 }; 1234 1235 #ifndef PRODUCT 1236 static int deps_find_witness_calls = 0; 1237 static int deps_find_witness_steps = 0; 1238 static int deps_find_witness_recursions = 0; 1239 static int deps_find_witness_singles = 0; 1240 static int deps_find_witness_print = 0; // set to -1 to force a final print 1241 static bool count_find_witness_calls() { 1242 if (TraceDependencies || LogCompilation) { 1243 int pcount = deps_find_witness_print + 1; 1244 bool final_stats = (pcount == 0); 1245 bool initial_call = (pcount == 1); 1246 bool occasional_print = ((pcount & ((1<<10) - 1)) == 0); 1247 if (pcount < 0) pcount = 1; // crude overflow protection 1248 deps_find_witness_print = pcount; 1249 if (VerifyDependencies && initial_call) { 1250 tty->print_cr("Warning: TraceDependencies results may be inflated by VerifyDependencies"); 1251 } 1252 if (occasional_print || final_stats) { 1253 // Every now and then dump a little info about dependency searching. 1254 if (xtty != NULL) { 1255 ttyLocker ttyl; 1256 xtty->elem("deps_find_witness calls='%d' steps='%d' recursions='%d' singles='%d'", 1257 deps_find_witness_calls, 1258 deps_find_witness_steps, 1259 deps_find_witness_recursions, 1260 deps_find_witness_singles); 1261 } 1262 if (final_stats || (TraceDependencies && WizardMode)) { 1263 ttyLocker ttyl; 1264 tty->print_cr("Dependency check (find_witness) " 1265 "calls=%d, steps=%d (avg=%.1f), recursions=%d, singles=%d", 1266 deps_find_witness_calls, 1267 deps_find_witness_steps, 1268 (double)deps_find_witness_steps / deps_find_witness_calls, 1269 deps_find_witness_recursions, 1270 deps_find_witness_singles); 1271 } 1272 } 1273 return true; 1274 } 1275 return false; 1276 } 1277 #else 1278 #define count_find_witness_calls() (0) 1279 #endif //PRODUCT 1280 1281 1282 Klass* ClassHierarchyWalker::find_witness_in(KlassDepChange& changes, 1283 Klass* context_type, 1284 bool participants_hide_witnesses) { 1285 assert(changes.involves_context(context_type), "irrelevant dependency"); 1286 Klass* new_type = changes.new_type(); 1287 1288 (void)count_find_witness_calls(); 1289 NOT_PRODUCT(deps_find_witness_singles++); 1290 1291 // Current thread must be in VM (not native mode, as in CI): 1292 assert(must_be_in_vm(), "raw oops here"); 1293 // Must not move the class hierarchy during this check: 1294 assert_locked_or_safepoint(Compile_lock); 1295 1296 int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); 1297 if (nof_impls > 1) { 1298 // Avoid this case: *I.m > { A.m, C }; B.m > C 1299 // %%% Until this is fixed more systematically, bail out. 1300 // See corresponding comment in find_witness_anywhere. 1301 return context_type; 1302 } 1303 1304 assert(!is_participant(new_type), "only old classes are participants"); 1305 if (participants_hide_witnesses) { 1306 // If the new type is a subtype of a participant, we are done. 1307 for (int i = 0; i < num_participants(); i++) { 1308 Klass* part = participant(i); 1309 if (part == NULL) continue; 1310 assert(changes.involves_context(part) == new_type->is_subtype_of(part), 1311 "correct marking of participants, b/c new_type is unique"); 1312 if (changes.involves_context(part)) { 1313 // new guy is protected from this check by previous participant 1314 return NULL; 1315 } 1316 } 1317 } 1318 1319 if (is_witness(new_type) && 1320 !ignore_witness(new_type)) { 1321 return new_type; 1322 } 1323 1324 return NULL; 1325 } 1326 1327 1328 // Walk hierarchy under a context type, looking for unexpected types. 1329 // Do not report participant types, and recursively walk beneath 1330 // them only if participants_hide_witnesses is false. 1331 // If top_level_call is false, skip testing the context type, 1332 // because the caller has already considered it. 1333 Klass* ClassHierarchyWalker::find_witness_anywhere(Klass* context_type, 1334 bool participants_hide_witnesses, 1335 bool top_level_call) { 1336 // Current thread must be in VM (not native mode, as in CI): 1337 assert(must_be_in_vm(), "raw oops here"); 1338 // Must not move the class hierarchy during this check: 1339 assert_locked_or_safepoint(Compile_lock); 1340 1341 bool do_counts = count_find_witness_calls(); 1342 1343 // Check the root of the sub-hierarchy first. 1344 if (top_level_call) { 1345 if (do_counts) { 1346 NOT_PRODUCT(deps_find_witness_calls++); 1347 NOT_PRODUCT(deps_find_witness_steps++); 1348 } 1349 if (is_participant(context_type)) { 1350 if (participants_hide_witnesses) return NULL; 1351 // else fall through to search loop... 1352 } else if (is_witness(context_type) && !ignore_witness(context_type)) { 1353 // The context is an abstract class or interface, to start with. 1354 return context_type; 1355 } 1356 } 1357 1358 // Now we must check each implementor and each subclass. 1359 // Use a short worklist to avoid blowing the stack. 1360 // Each worklist entry is a *chain* of subklass siblings to process. 1361 const int CHAINMAX = 100; // >= 1 + InstanceKlass::implementors_limit 1362 Klass* chains[CHAINMAX]; 1363 int chaini = 0; // index into worklist 1364 Klass* chain; // scratch variable 1365 #define ADD_SUBCLASS_CHAIN(k) { \ 1366 assert(chaini < CHAINMAX, "oob"); \ 1367 chain = k->subklass(); \ 1368 if (chain != NULL) chains[chaini++] = chain; } 1369 1370 // Look for non-abstract subclasses. 1371 // (Note: Interfaces do not have subclasses.) 1372 ADD_SUBCLASS_CHAIN(context_type); 1373 1374 // If it is an interface, search its direct implementors. 1375 // (Their subclasses are additional indirect implementors. 1376 // See InstanceKlass::add_implementor.) 1377 // (Note: nof_implementors is always zero for non-interfaces.) 1378 if (top_level_call) { 1379 int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); 1380 if (nof_impls > 1) { 1381 // Avoid this case: *I.m > { A.m, C }; B.m > C 1382 // Here, I.m has 2 concrete implementations, but m appears unique 1383 // as A.m, because the search misses B.m when checking C. 1384 // The inherited method B.m was getting missed by the walker 1385 // when interface 'I' was the starting point. 1386 // %%% Until this is fixed more systematically, bail out. 1387 // (Old CHA had the same limitation.) 1388 return context_type; 1389 } 1390 if (nof_impls > 0) { 1391 Klass* impl = InstanceKlass::cast(context_type)->implementor(); 1392 assert(impl != NULL, "just checking"); 1393 // If impl is the same as the context_type, then more than one 1394 // implementor has seen. No exact info in this case. 1395 if (impl == context_type) { 1396 return context_type; // report an inexact witness to this sad affair 1397 } 1398 if (do_counts) 1399 { NOT_PRODUCT(deps_find_witness_steps++); } 1400 if (is_participant(impl)) { 1401 if (!participants_hide_witnesses) { 1402 ADD_SUBCLASS_CHAIN(impl); 1403 } 1404 } else if (is_witness(impl) && !ignore_witness(impl)) { 1405 return impl; 1406 } else { 1407 ADD_SUBCLASS_CHAIN(impl); 1408 } 1409 } 1410 } 1411 1412 // Recursively process each non-trivial sibling chain. 1413 while (chaini > 0) { 1414 Klass* chain = chains[--chaini]; 1415 for (Klass* sub = chain; sub != NULL; sub = sub->next_sibling()) { 1416 if (do_counts) { NOT_PRODUCT(deps_find_witness_steps++); } 1417 if (is_participant(sub)) { 1418 if (participants_hide_witnesses) continue; 1419 // else fall through to process this guy's subclasses 1420 } else if (is_witness(sub) && !ignore_witness(sub)) { 1421 return sub; 1422 } 1423 if (chaini < (VerifyDependencies? 2: CHAINMAX)) { 1424 // Fast path. (Partially disabled if VerifyDependencies.) 1425 ADD_SUBCLASS_CHAIN(sub); 1426 } else { 1427 // Worklist overflow. Do a recursive call. Should be rare. 1428 // The recursive call will have its own worklist, of course. 1429 // (Note that sub has already been tested, so that there is 1430 // no need for the recursive call to re-test. That's handy, 1431 // since the recursive call sees sub as the context_type.) 1432 if (do_counts) { NOT_PRODUCT(deps_find_witness_recursions++); } 1433 Klass* witness = find_witness_anywhere(sub, 1434 participants_hide_witnesses, 1435 /*top_level_call=*/ false); 1436 if (witness != NULL) return witness; 1437 } 1438 } 1439 } 1440 1441 // No witness found. The dependency remains unbroken. 1442 return NULL; 1443 #undef ADD_SUBCLASS_CHAIN 1444 } 1445 1446 1447 bool Dependencies::is_concrete_klass(Klass* k) { 1448 if (k->is_abstract()) return false; 1449 // %%% We could treat classes which are concrete but 1450 // have not yet been instantiated as virtually abstract. 1451 // This would require a deoptimization barrier on first instantiation. 1452 //if (k->is_not_instantiated()) return false; 1453 return true; 1454 } 1455 1456 bool Dependencies::is_concrete_method(Method* m, Klass * k) { 1457 // NULL is not a concrete method, 1458 // statics are irrelevant to virtual call sites, 1459 // abstract methods are not concrete, 1460 // overpass (error) methods are not concrete if k is abstract 1461 // 1462 // note "true" is conservative answer -- 1463 // overpass clause is false if k == NULL, implies return true if 1464 // answer depends on overpass clause. 1465 return ! ( m == NULL || m -> is_static() || m -> is_abstract() || 1466 (m->is_overpass() && k != NULL && k -> is_abstract()) ); 1467 } 1468 1469 1470 Klass* Dependencies::find_finalizable_subclass(Klass* k) { 1471 if (k->is_interface()) return NULL; 1472 if (k->has_finalizer()) return k; 1473 k = k->subklass(); 1474 while (k != NULL) { 1475 Klass* result = find_finalizable_subclass(k); 1476 if (result != NULL) return result; 1477 k = k->next_sibling(); 1478 } 1479 return NULL; 1480 } 1481 1482 1483 bool Dependencies::is_concrete_klass(ciInstanceKlass* k) { 1484 if (k->is_abstract()) return false; 1485 // We could also return false if k does not yet appear to be 1486 // instantiated, if the VM version supports this distinction also. 1487 //if (k->is_not_instantiated()) return false; 1488 return true; 1489 } 1490 1491 bool Dependencies::has_finalizable_subclass(ciInstanceKlass* k) { 1492 return k->has_finalizable_subclass(); 1493 } 1494 1495 1496 // Any use of the contents (bytecodes) of a method must be 1497 // marked by an "evol_method" dependency, if those contents 1498 // can change. (Note: A method is always dependent on itself.) 1499 Klass* Dependencies::check_evol_method(Method* m) { 1500 assert(must_be_in_vm(), "raw oops here"); 1501 // Did somebody do a JVMTI RedefineClasses while our backs were turned? 1502 // Or is there a now a breakpoint? 1503 // (Assumes compiled code cannot handle bkpts; change if UseFastBreakpoints.) 1504 if (m->is_old() 1505 || m->number_of_breakpoints() > 0) { 1506 return m->method_holder(); 1507 } else { 1508 return NULL; 1509 } 1510 } 1511 1512 // This is a strong assertion: It is that the given type 1513 // has no subtypes whatever. It is most useful for 1514 // optimizing checks on reflected types or on array types. 1515 // (Checks on types which are derived from real instances 1516 // can be optimized more strongly than this, because we 1517 // know that the checked type comes from a concrete type, 1518 // and therefore we can disregard abstract types.) 1519 Klass* Dependencies::check_leaf_type(Klass* ctxk) { 1520 assert(must_be_in_vm(), "raw oops here"); 1521 assert_locked_or_safepoint(Compile_lock); 1522 InstanceKlass* ctx = InstanceKlass::cast(ctxk); 1523 Klass* sub = ctx->subklass(); 1524 if (sub != NULL) { 1525 return sub; 1526 } else if (ctx->nof_implementors() != 0) { 1527 // if it is an interface, it must be unimplemented 1528 // (if it is not an interface, nof_implementors is always zero) 1529 Klass* impl = ctx->implementor(); 1530 assert(impl != NULL, "must be set"); 1531 return impl; 1532 } else { 1533 return NULL; 1534 } 1535 } 1536 1537 // Test the assertion that conck is the only concrete subtype* of ctxk. 1538 // The type conck itself is allowed to have have further concrete subtypes. 1539 // This allows the compiler to narrow occurrences of ctxk by conck, 1540 // when dealing with the types of actual instances. 1541 Klass* Dependencies::check_abstract_with_unique_concrete_subtype(Klass* ctxk, 1542 Klass* conck, 1543 KlassDepChange* changes) { 1544 ClassHierarchyWalker wf(conck); 1545 return wf.find_witness_subtype(ctxk, changes); 1546 } 1547 1548 // If a non-concrete class has no concrete subtypes, it is not (yet) 1549 // instantiatable. This can allow the compiler to make some paths go 1550 // dead, if they are gated by a test of the type. 1551 Klass* Dependencies::check_abstract_with_no_concrete_subtype(Klass* ctxk, 1552 KlassDepChange* changes) { 1553 // Find any concrete subtype, with no participants: 1554 ClassHierarchyWalker wf; 1555 return wf.find_witness_subtype(ctxk, changes); 1556 } 1557 1558 1559 // If a concrete class has no concrete subtypes, it can always be 1560 // exactly typed. This allows the use of a cheaper type test. 1561 Klass* Dependencies::check_concrete_with_no_concrete_subtype(Klass* ctxk, 1562 KlassDepChange* changes) { 1563 // Find any concrete subtype, with only the ctxk as participant: 1564 ClassHierarchyWalker wf(ctxk); 1565 return wf.find_witness_subtype(ctxk, changes); 1566 } 1567 1568 1569 // Find the unique concrete proper subtype of ctxk, or NULL if there 1570 // is more than one concrete proper subtype. If there are no concrete 1571 // proper subtypes, return ctxk itself, whether it is concrete or not. 1572 // The returned subtype is allowed to have have further concrete subtypes. 1573 // That is, return CC1 for CX > CC1 > CC2, but NULL for CX > { CC1, CC2 }. 1574 Klass* Dependencies::find_unique_concrete_subtype(Klass* ctxk) { 1575 ClassHierarchyWalker wf(ctxk); // Ignore ctxk when walking. 1576 wf.record_witnesses(1); // Record one other witness when walking. 1577 Klass* wit = wf.find_witness_subtype(ctxk); 1578 if (wit != NULL) return NULL; // Too many witnesses. 1579 Klass* conck = wf.participant(0); 1580 if (conck == NULL) { 1581 #ifndef PRODUCT 1582 // Make sure the dependency mechanism will pass this discovery: 1583 if (VerifyDependencies) { 1584 // Turn off dependency tracing while actually testing deps. 1585 FlagSetting fs(TraceDependencies, false); 1586 if (!Dependencies::is_concrete_klass(ctxk)) { 1587 guarantee(NULL == 1588 (void *)check_abstract_with_no_concrete_subtype(ctxk), 1589 "verify dep."); 1590 } else { 1591 guarantee(NULL == 1592 (void *)check_concrete_with_no_concrete_subtype(ctxk), 1593 "verify dep."); 1594 } 1595 } 1596 #endif //PRODUCT 1597 return ctxk; // Return ctxk as a flag for "no subtypes". 1598 } else { 1599 #ifndef PRODUCT 1600 // Make sure the dependency mechanism will pass this discovery: 1601 if (VerifyDependencies) { 1602 // Turn off dependency tracing while actually testing deps. 1603 FlagSetting fs(TraceDependencies, false); 1604 if (!Dependencies::is_concrete_klass(ctxk)) { 1605 guarantee(NULL == (void *) 1606 check_abstract_with_unique_concrete_subtype(ctxk, conck), 1607 "verify dep."); 1608 } 1609 } 1610 #endif //PRODUCT 1611 return conck; 1612 } 1613 } 1614 1615 // Test the assertion that the k[12] are the only concrete subtypes of ctxk, 1616 // except possibly for further subtypes of k[12] themselves. 1617 // The context type must be abstract. The types k1 and k2 are themselves 1618 // allowed to have further concrete subtypes. 1619 Klass* Dependencies::check_abstract_with_exclusive_concrete_subtypes( 1620 Klass* ctxk, 1621 Klass* k1, 1622 Klass* k2, 1623 KlassDepChange* changes) { 1624 ClassHierarchyWalker wf; 1625 wf.add_participant(k1); 1626 wf.add_participant(k2); 1627 return wf.find_witness_subtype(ctxk, changes); 1628 } 1629 1630 // Search ctxk for concrete implementations. If there are klen or fewer, 1631 // pack them into the given array and return the number. 1632 // Otherwise, return -1, meaning the given array would overflow. 1633 // (Note that a return of 0 means there are exactly no concrete subtypes.) 1634 // In this search, if ctxk is concrete, it will be reported alone. 1635 // For any type CC reported, no proper subtypes of CC will be reported. 1636 int Dependencies::find_exclusive_concrete_subtypes(Klass* ctxk, 1637 int klen, 1638 Klass* karray[]) { 1639 ClassHierarchyWalker wf; 1640 wf.record_witnesses(klen); 1641 Klass* wit = wf.find_witness_subtype(ctxk); 1642 if (wit != NULL) return -1; // Too many witnesses. 1643 int num = wf.num_participants(); 1644 assert(num <= klen, "oob"); 1645 // Pack the result array with the good news. 1646 for (int i = 0; i < num; i++) 1647 karray[i] = wf.participant(i); 1648 #ifndef PRODUCT 1649 // Make sure the dependency mechanism will pass this discovery: 1650 if (VerifyDependencies) { 1651 // Turn off dependency tracing while actually testing deps. 1652 FlagSetting fs(TraceDependencies, false); 1653 switch (Dependencies::is_concrete_klass(ctxk)? -1: num) { 1654 case -1: // ctxk was itself concrete 1655 guarantee(num == 1 && karray[0] == ctxk, "verify dep."); 1656 break; 1657 case 0: 1658 guarantee(NULL == (void *)check_abstract_with_no_concrete_subtype(ctxk), 1659 "verify dep."); 1660 break; 1661 case 1: 1662 guarantee(NULL == (void *) 1663 check_abstract_with_unique_concrete_subtype(ctxk, karray[0]), 1664 "verify dep."); 1665 break; 1666 case 2: 1667 guarantee(NULL == (void *) 1668 check_abstract_with_exclusive_concrete_subtypes(ctxk, 1669 karray[0], 1670 karray[1]), 1671 "verify dep."); 1672 break; 1673 default: 1674 ShouldNotReachHere(); // klen > 2 yet supported 1675 } 1676 } 1677 #endif //PRODUCT 1678 return num; 1679 } 1680 1681 // If a class (or interface) has a unique concrete method uniqm, return NULL. 1682 // Otherwise, return a class that contains an interfering method. 1683 Klass* Dependencies::check_unique_concrete_method(Klass* ctxk, Method* uniqm, 1684 KlassDepChange* changes) { 1685 // Here is a missing optimization: If uniqm->is_final(), 1686 // we don't really need to search beneath it for overrides. 1687 // This is probably not important, since we don't use dependencies 1688 // to track final methods. (They can't be "definalized".) 1689 ClassHierarchyWalker wf(uniqm->method_holder(), uniqm); 1690 return wf.find_witness_definer(ctxk, changes); 1691 } 1692 1693 // Find the set of all non-abstract methods under ctxk that match m. 1694 // (The method m must be defined or inherited in ctxk.) 1695 // Include m itself in the set, unless it is abstract. 1696 // If this set has exactly one element, return that element. 1697 Method* Dependencies::find_unique_concrete_method(Klass* ctxk, Method* m) { 1698 // Return NULL if m is marked old; must have been a redefined method. 1699 if (m->is_old()) { 1700 return NULL; 1701 } 1702 ClassHierarchyWalker wf(m); 1703 assert(wf.check_method_context(ctxk, m), "proper context"); 1704 wf.record_witnesses(1); 1705 Klass* wit = wf.find_witness_definer(ctxk); 1706 if (wit != NULL) return NULL; // Too many witnesses. 1707 Method* fm = wf.found_method(0); // Will be NULL if num_parts == 0. 1708 if (Dependencies::is_concrete_method(m, ctxk)) { 1709 if (fm == NULL) { 1710 // It turns out that m was always the only implementation. 1711 fm = m; 1712 } else if (fm != m) { 1713 // Two conflicting implementations after all. 1714 // (This can happen if m is inherited into ctxk and fm overrides it.) 1715 return NULL; 1716 } 1717 } 1718 #ifndef PRODUCT 1719 // Make sure the dependency mechanism will pass this discovery: 1720 if (VerifyDependencies && fm != NULL) { 1721 guarantee(NULL == (void *)check_unique_concrete_method(ctxk, fm), 1722 "verify dep."); 1723 } 1724 #endif //PRODUCT 1725 return fm; 1726 } 1727 1728 Klass* Dependencies::check_exclusive_concrete_methods(Klass* ctxk, 1729 Method* m1, 1730 Method* m2, 1731 KlassDepChange* changes) { 1732 ClassHierarchyWalker wf(m1); 1733 wf.add_participant(m1->method_holder()); 1734 wf.add_participant(m2->method_holder()); 1735 return wf.find_witness_definer(ctxk, changes); 1736 } 1737 1738 Klass* Dependencies::check_has_no_finalizable_subclasses(Klass* ctxk, KlassDepChange* changes) { 1739 Klass* search_at = ctxk; 1740 if (changes != NULL) 1741 search_at = changes->new_type(); // just look at the new bit 1742 return find_finalizable_subclass(search_at); 1743 } 1744 1745 Klass* Dependencies::check_call_site_target_value(oop call_site, oop method_handle, CallSiteDepChange* changes) { 1746 assert(!oopDesc::is_null(call_site), "sanity"); 1747 assert(!oopDesc::is_null(method_handle), "sanity"); 1748 assert(call_site->is_a(SystemDictionary::CallSite_klass()), "sanity"); 1749 1750 if (changes == NULL) { 1751 // Validate all CallSites 1752 if (java_lang_invoke_CallSite::target(call_site) != method_handle) 1753 return call_site->klass(); // assertion failed 1754 } else { 1755 // Validate the given CallSite 1756 if (call_site == changes->call_site() && java_lang_invoke_CallSite::target(call_site) != changes->method_handle()) { 1757 assert(method_handle != changes->method_handle(), "must be"); 1758 return call_site->klass(); // assertion failed 1759 } 1760 } 1761 return NULL; // assertion still valid 1762 } 1763 1764 void Dependencies::DepStream::trace_and_log_witness(Klass* witness) { 1765 if (witness != NULL) { 1766 if (TraceDependencies) { 1767 print_dependency(witness, /*verbose=*/ true); 1768 } 1769 // The following is a no-op unless logging is enabled: 1770 log_dependency(witness); 1771 } 1772 } 1773 1774 1775 Klass* Dependencies::DepStream::check_klass_dependency(KlassDepChange* changes) { 1776 assert_locked_or_safepoint(Compile_lock); 1777 Dependencies::check_valid_dependency_type(type()); 1778 1779 Klass* witness = NULL; 1780 switch (type()) { 1781 case evol_method: 1782 witness = check_evol_method(method_argument(0)); 1783 break; 1784 case leaf_type: 1785 witness = check_leaf_type(context_type()); 1786 break; 1787 case abstract_with_unique_concrete_subtype: 1788 witness = check_abstract_with_unique_concrete_subtype(context_type(), type_argument(1), changes); 1789 break; 1790 case abstract_with_no_concrete_subtype: 1791 witness = check_abstract_with_no_concrete_subtype(context_type(), changes); 1792 break; 1793 case concrete_with_no_concrete_subtype: 1794 witness = check_concrete_with_no_concrete_subtype(context_type(), changes); 1795 break; 1796 case unique_concrete_method: 1797 witness = check_unique_concrete_method(context_type(), method_argument(1), changes); 1798 break; 1799 case abstract_with_exclusive_concrete_subtypes_2: 1800 witness = check_abstract_with_exclusive_concrete_subtypes(context_type(), type_argument(1), type_argument(2), changes); 1801 break; 1802 case exclusive_concrete_methods_2: 1803 witness = check_exclusive_concrete_methods(context_type(), method_argument(1), method_argument(2), changes); 1804 break; 1805 case no_finalizable_subclasses: 1806 witness = check_has_no_finalizable_subclasses(context_type(), changes); 1807 break; 1808 default: 1809 witness = NULL; 1810 break; 1811 } 1812 trace_and_log_witness(witness); 1813 return witness; 1814 } 1815 1816 1817 Klass* Dependencies::DepStream::check_call_site_dependency(CallSiteDepChange* changes) { 1818 assert_locked_or_safepoint(Compile_lock); 1819 Dependencies::check_valid_dependency_type(type()); 1820 1821 Klass* witness = NULL; 1822 switch (type()) { 1823 case call_site_target_value: 1824 witness = check_call_site_target_value(argument_oop(0), argument_oop(1), changes); 1825 break; 1826 default: 1827 witness = NULL; 1828 break; 1829 } 1830 trace_and_log_witness(witness); 1831 return witness; 1832 } 1833 1834 1835 Klass* Dependencies::DepStream::spot_check_dependency_at(DepChange& changes) { 1836 // Handle klass dependency 1837 if (changes.is_klass_change() && changes.as_klass_change()->involves_context(context_type())) 1838 return check_klass_dependency(changes.as_klass_change()); 1839 1840 // Handle CallSite dependency 1841 if (changes.is_call_site_change()) 1842 return check_call_site_dependency(changes.as_call_site_change()); 1843 1844 // irrelevant dependency; skip it 1845 return NULL; 1846 } 1847 1848 1849 void DepChange::print() { 1850 int nsup = 0, nint = 0; 1851 for (ContextStream str(*this); str.next(); ) { 1852 Klass* k = str.klass(); 1853 switch (str.change_type()) { 1854 case Change_new_type: 1855 tty->print_cr(" dependee = %s", k->external_name()); 1856 break; 1857 case Change_new_sub: 1858 if (!WizardMode) { 1859 ++nsup; 1860 } else { 1861 tty->print_cr(" context super = %s", k->external_name()); 1862 } 1863 break; 1864 case Change_new_impl: 1865 if (!WizardMode) { 1866 ++nint; 1867 } else { 1868 tty->print_cr(" context interface = %s", k->external_name()); 1869 } 1870 break; 1871 default: 1872 break; 1873 } 1874 } 1875 if (nsup + nint != 0) { 1876 tty->print_cr(" context supers = %d, interfaces = %d", nsup, nint); 1877 } 1878 } 1879 1880 void DepChange::ContextStream::start() { 1881 Klass* new_type = _changes.is_klass_change() ? _changes.as_klass_change()->new_type() : (Klass*) NULL; 1882 _change_type = (new_type == NULL ? NO_CHANGE : Start_Klass); 1883 _klass = new_type; 1884 _ti_base = NULL; 1885 _ti_index = 0; 1886 _ti_limit = 0; 1887 } 1888 1889 bool DepChange::ContextStream::next() { 1890 switch (_change_type) { 1891 case Start_Klass: // initial state; _klass is the new type 1892 _ti_base = InstanceKlass::cast(_klass)->transitive_interfaces(); 1893 _ti_index = 0; 1894 _change_type = Change_new_type; 1895 return true; 1896 case Change_new_type: 1897 // fall through: 1898 _change_type = Change_new_sub; 1899 case Change_new_sub: 1900 // 6598190: brackets workaround Sun Studio C++ compiler bug 6629277 1901 { 1902 _klass = _klass->super(); 1903 if (_klass != NULL) { 1904 return true; 1905 } 1906 } 1907 // else set up _ti_limit and fall through: 1908 _ti_limit = (_ti_base == NULL) ? 0 : _ti_base->length(); 1909 _change_type = Change_new_impl; 1910 case Change_new_impl: 1911 if (_ti_index < _ti_limit) { 1912 _klass = _ti_base->at(_ti_index++); 1913 return true; 1914 } 1915 // fall through: 1916 _change_type = NO_CHANGE; // iterator is exhausted 1917 case NO_CHANGE: 1918 break; 1919 default: 1920 ShouldNotReachHere(); 1921 } 1922 return false; 1923 } 1924 1925 void KlassDepChange::initialize() { 1926 // entire transaction must be under this lock: 1927 assert_lock_strong(Compile_lock); 1928 1929 // Mark all dependee and all its superclasses 1930 // Mark transitive interfaces 1931 for (ContextStream str(*this); str.next(); ) { 1932 Klass* d = str.klass(); 1933 assert(!InstanceKlass::cast(d)->is_marked_dependent(), "checking"); 1934 InstanceKlass::cast(d)->set_is_marked_dependent(true); 1935 } 1936 } 1937 1938 KlassDepChange::~KlassDepChange() { 1939 // Unmark all dependee and all its superclasses 1940 // Unmark transitive interfaces 1941 for (ContextStream str(*this); str.next(); ) { 1942 Klass* d = str.klass(); 1943 InstanceKlass::cast(d)->set_is_marked_dependent(false); 1944 } 1945 } 1946 1947 bool KlassDepChange::involves_context(Klass* k) { 1948 if (k == NULL || !k->is_instance_klass()) { 1949 return false; 1950 } 1951 InstanceKlass* ik = InstanceKlass::cast(k); 1952 bool is_contained = ik->is_marked_dependent(); 1953 assert(is_contained == new_type()->is_subtype_of(k), 1954 "correct marking of potential context types"); 1955 return is_contained; 1956 } 1957 1958 #ifndef PRODUCT 1959 void Dependencies::print_statistics() { 1960 if (deps_find_witness_print != 0) { 1961 // Call one final time, to flush out the data. 1962 deps_find_witness_print = -1; 1963 count_find_witness_calls(); 1964 } 1965 } 1966 #endif 1967 1968 CallSiteDepChange::CallSiteDepChange(Handle call_site, Handle method_handle) : 1969 _call_site(call_site), 1970 _method_handle(method_handle) { 1971 assert(_call_site()->is_a(SystemDictionary::CallSite_klass()), "must be"); 1972 assert(_method_handle.is_null() || _method_handle()->is_a(SystemDictionary::MethodHandle_klass()), "must be"); 1973 }