1 /* 2 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "ci/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 "compiler/compileBroker.hpp" 34 #include "compiler/compileTask.hpp" 35 #include "memory/resourceArea.hpp" 36 #include "oops/oop.inline.hpp" 37 #include "oops/objArrayKlass.hpp" 38 #include "runtime/handles.hpp" 39 #include "runtime/handles.inline.hpp" 40 #include "runtime/jniHandles.inline.hpp" 41 #include "runtime/thread.inline.hpp" 42 #include "utilities/copy.hpp" 43 44 45 #ifdef ASSERT 46 static bool must_be_in_vm() { 47 Thread* thread = Thread::current(); 48 if (thread->is_Java_thread()) 49 return ((JavaThread*)thread)->thread_state() == _thread_in_vm; 50 else 51 return true; //something like this: thread->is_VM_thread(); 52 } 53 #endif //ASSERT 54 55 void Dependencies::initialize(ciEnv* env) { 56 Arena* arena = env->arena(); 57 _oop_recorder = env->oop_recorder(); 58 _log = env->log(); 59 _dep_seen = new(arena) GrowableArray<int>(arena, 500, 0, 0); 60 #if INCLUDE_JVMCI 61 _using_dep_values = false; 62 #endif 63 DEBUG_ONLY(_deps[end_marker] = NULL); 64 for (int i = (int)FIRST_TYPE; i < (int)TYPE_LIMIT; i++) { 65 _deps[i] = new(arena) GrowableArray<ciBaseObject*>(arena, 10, 0, 0); 66 } 67 _content_bytes = NULL; 68 _size_in_bytes = (size_t)-1; 69 70 assert(TYPE_LIMIT <= (1<<LG2_TYPE_LIMIT), "sanity"); 71 } 72 73 void Dependencies::assert_evol_method(ciMethod* m) { 74 assert_common_1(evol_method, m); 75 } 76 77 void Dependencies::assert_leaf_type(ciKlass* ctxk) { 78 if (ctxk->is_array_klass()) { 79 // As a special case, support this assertion on an array type, 80 // which reduces to an assertion on its element type. 81 // Note that this cannot be done with assertions that 82 // relate to concreteness or abstractness. 83 ciType* elemt = ctxk->as_array_klass()->base_element_type(); 84 if (!elemt->is_instance_klass()) return; // Ex: int[][] 85 ctxk = elemt->as_instance_klass(); 86 //if (ctxk->is_final()) return; // Ex: String[][] 87 } 88 check_ctxk(ctxk); 89 assert_common_1(leaf_type, ctxk); 90 } 91 92 void Dependencies::assert_abstract_with_unique_concrete_subtype(ciKlass* ctxk, ciKlass* conck) { 93 check_ctxk_abstract(ctxk); 94 assert_common_2(abstract_with_unique_concrete_subtype, ctxk, conck); 95 } 96 97 void Dependencies::assert_abstract_with_no_concrete_subtype(ciKlass* ctxk) { 98 check_ctxk_abstract(ctxk); 99 assert_common_1(abstract_with_no_concrete_subtype, ctxk); 100 } 101 102 void Dependencies::assert_concrete_with_no_concrete_subtype(ciKlass* ctxk) { 103 check_ctxk_concrete(ctxk); 104 assert_common_1(concrete_with_no_concrete_subtype, ctxk); 105 } 106 107 void Dependencies::assert_unique_concrete_method(ciKlass* ctxk, ciMethod* uniqm) { 108 check_ctxk(ctxk); 109 assert_common_2(unique_concrete_method, ctxk, uniqm); 110 } 111 112 void Dependencies::assert_abstract_with_exclusive_concrete_subtypes(ciKlass* ctxk, ciKlass* k1, ciKlass* k2) { 113 check_ctxk(ctxk); 114 assert_common_3(abstract_with_exclusive_concrete_subtypes_2, ctxk, k1, k2); 115 } 116 117 void Dependencies::assert_exclusive_concrete_methods(ciKlass* ctxk, ciMethod* m1, ciMethod* m2) { 118 check_ctxk(ctxk); 119 assert_common_3(exclusive_concrete_methods_2, ctxk, m1, m2); 120 } 121 122 void Dependencies::assert_has_no_finalizable_subclasses(ciKlass* ctxk) { 123 check_ctxk(ctxk); 124 assert_common_1(no_finalizable_subclasses, ctxk); 125 } 126 127 void Dependencies::assert_call_site_target_value(ciCallSite* call_site, ciMethodHandle* method_handle) { 128 assert_common_2(call_site_target_value, call_site, method_handle); 129 } 130 131 #if INCLUDE_JVMCI 132 133 Dependencies::Dependencies(Arena* arena, OopRecorder* oop_recorder, CompileLog* log) { 134 _oop_recorder = oop_recorder; 135 _log = log; 136 _dep_seen = new(arena) GrowableArray<int>(arena, 500, 0, 0); 137 _using_dep_values = true; 138 DEBUG_ONLY(_dep_values[end_marker] = NULL); 139 for (int i = (int)FIRST_TYPE; i < (int)TYPE_LIMIT; i++) { 140 _dep_values[i] = new(arena) GrowableArray<DepValue>(arena, 10, 0, DepValue()); 141 } 142 _content_bytes = NULL; 143 _size_in_bytes = (size_t)-1; 144 145 assert(TYPE_LIMIT <= (1<<LG2_TYPE_LIMIT), "sanity"); 146 } 147 148 void Dependencies::assert_evol_method(Method* m) { 149 assert_common_1(evol_method, DepValue(_oop_recorder, m)); 150 } 151 152 void Dependencies::assert_has_no_finalizable_subclasses(Klass* ctxk) { 153 check_ctxk(ctxk); 154 assert_common_1(no_finalizable_subclasses, DepValue(_oop_recorder, ctxk)); 155 } 156 157 void Dependencies::assert_leaf_type(Klass* ctxk) { 158 if (ctxk->is_array_klass()) { 159 // As a special case, support this assertion on an array type, 160 // which reduces to an assertion on its element type. 161 // Note that this cannot be done with assertions that 162 // relate to concreteness or abstractness. 163 BasicType elemt = ArrayKlass::cast(ctxk)->element_type(); 164 if (is_java_primitive(elemt)) return; // Ex: int[][] 165 ctxk = ObjArrayKlass::cast(ctxk)->bottom_klass(); 166 //if (ctxk->is_final()) return; // Ex: String[][] 167 } 168 check_ctxk(ctxk); 169 assert_common_1(leaf_type, DepValue(_oop_recorder, ctxk)); 170 } 171 172 void Dependencies::assert_abstract_with_unique_concrete_subtype(Klass* ctxk, Klass* conck) { 173 check_ctxk_abstract(ctxk); 174 DepValue ctxk_dv(_oop_recorder, ctxk); 175 DepValue conck_dv(_oop_recorder, conck, &ctxk_dv); 176 assert_common_2(abstract_with_unique_concrete_subtype, ctxk_dv, conck_dv); 177 } 178 179 void Dependencies::assert_unique_concrete_method(Klass* ctxk, Method* uniqm) { 180 check_ctxk(ctxk); 181 assert_common_2(unique_concrete_method, DepValue(_oop_recorder, ctxk), DepValue(_oop_recorder, uniqm)); 182 } 183 184 void Dependencies::assert_call_site_target_value(oop call_site, oop method_handle) { 185 assert_common_2(call_site_target_value, DepValue(_oop_recorder, JNIHandles::make_local(call_site)), DepValue(_oop_recorder, JNIHandles::make_local(method_handle))); 186 } 187 188 #endif // INCLUDE_JVMCI 189 190 191 // Helper function. If we are adding a new dep. under ctxk2, 192 // try to find an old dep. under a broader* ctxk1. If there is 193 // 194 bool Dependencies::maybe_merge_ctxk(GrowableArray<ciBaseObject*>* deps, 195 int ctxk_i, ciKlass* ctxk2) { 196 ciKlass* ctxk1 = deps->at(ctxk_i)->as_metadata()->as_klass(); 197 if (ctxk2->is_subtype_of(ctxk1)) { 198 return true; // success, and no need to change 199 } else if (ctxk1->is_subtype_of(ctxk2)) { 200 // new context class fully subsumes previous one 201 deps->at_put(ctxk_i, ctxk2); 202 return true; 203 } else { 204 return false; 205 } 206 } 207 208 void Dependencies::assert_common_1(DepType dept, ciBaseObject* x) { 209 assert(dep_args(dept) == 1, "sanity"); 210 log_dependency(dept, x); 211 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 212 213 // see if the same (or a similar) dep is already recorded 214 if (note_dep_seen(dept, x)) { 215 assert(deps->find(x) >= 0, "sanity"); 216 } else { 217 deps->append(x); 218 } 219 } 220 221 void Dependencies::assert_common_2(DepType dept, 222 ciBaseObject* x0, ciBaseObject* x1) { 223 assert(dep_args(dept) == 2, "sanity"); 224 log_dependency(dept, x0, x1); 225 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 226 227 // see if the same (or a similar) dep is already recorded 228 bool has_ctxk = has_explicit_context_arg(dept); 229 if (has_ctxk) { 230 assert(dep_context_arg(dept) == 0, "sanity"); 231 if (note_dep_seen(dept, x1)) { 232 // look in this bucket for redundant assertions 233 const int stride = 2; 234 for (int i = deps->length(); (i -= stride) >= 0; ) { 235 ciBaseObject* y1 = deps->at(i+1); 236 if (x1 == y1) { // same subject; check the context 237 if (maybe_merge_ctxk(deps, i+0, x0->as_metadata()->as_klass())) { 238 return; 239 } 240 } 241 } 242 } 243 } else { 244 if (note_dep_seen(dept, x0) && note_dep_seen(dept, x1)) { 245 // look in this bucket for redundant assertions 246 const int stride = 2; 247 for (int i = deps->length(); (i -= stride) >= 0; ) { 248 ciBaseObject* y0 = deps->at(i+0); 249 ciBaseObject* y1 = deps->at(i+1); 250 if (x0 == y0 && x1 == y1) { 251 return; 252 } 253 } 254 } 255 } 256 257 // append the assertion in the correct bucket: 258 deps->append(x0); 259 deps->append(x1); 260 } 261 262 void Dependencies::assert_common_3(DepType dept, 263 ciKlass* ctxk, ciBaseObject* x, ciBaseObject* x2) { 264 assert(dep_context_arg(dept) == 0, "sanity"); 265 assert(dep_args(dept) == 3, "sanity"); 266 log_dependency(dept, ctxk, x, x2); 267 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 268 269 // try to normalize an unordered pair: 270 bool swap = false; 271 switch (dept) { 272 case abstract_with_exclusive_concrete_subtypes_2: 273 swap = (x->ident() > x2->ident() && x->as_metadata()->as_klass() != ctxk); 274 break; 275 case exclusive_concrete_methods_2: 276 swap = (x->ident() > x2->ident() && x->as_metadata()->as_method()->holder() != ctxk); 277 break; 278 default: 279 break; 280 } 281 if (swap) { ciBaseObject* t = x; x = x2; x2 = t; } 282 283 // see if the same (or a similar) dep is already recorded 284 if (note_dep_seen(dept, x) && note_dep_seen(dept, x2)) { 285 // look in this bucket for redundant assertions 286 const int stride = 3; 287 for (int i = deps->length(); (i -= stride) >= 0; ) { 288 ciBaseObject* y = deps->at(i+1); 289 ciBaseObject* y2 = deps->at(i+2); 290 if (x == y && x2 == y2) { // same subjects; check the context 291 if (maybe_merge_ctxk(deps, i+0, ctxk)) { 292 return; 293 } 294 } 295 } 296 } 297 // append the assertion in the correct bucket: 298 deps->append(ctxk); 299 deps->append(x); 300 deps->append(x2); 301 } 302 303 #if INCLUDE_JVMCI 304 bool Dependencies::maybe_merge_ctxk(GrowableArray<DepValue>* deps, 305 int ctxk_i, DepValue ctxk2_dv) { 306 Klass* ctxk1 = deps->at(ctxk_i).as_klass(_oop_recorder); 307 Klass* ctxk2 = ctxk2_dv.as_klass(_oop_recorder); 308 if (ctxk2->is_subtype_of(ctxk1)) { 309 return true; // success, and no need to change 310 } else if (ctxk1->is_subtype_of(ctxk2)) { 311 // new context class fully subsumes previous one 312 deps->at_put(ctxk_i, ctxk2_dv); 313 return true; 314 } else { 315 return false; 316 } 317 } 318 319 void Dependencies::assert_common_1(DepType dept, DepValue x) { 320 assert(dep_args(dept) == 1, "sanity"); 321 //log_dependency(dept, x); 322 GrowableArray<DepValue>* deps = _dep_values[dept]; 323 324 // see if the same (or a similar) dep is already recorded 325 if (note_dep_seen(dept, x)) { 326 assert(deps->find(x) >= 0, "sanity"); 327 } else { 328 deps->append(x); 329 } 330 } 331 332 void Dependencies::assert_common_2(DepType dept, 333 DepValue x0, DepValue x1) { 334 assert(dep_args(dept) == 2, "sanity"); 335 //log_dependency(dept, x0, x1); 336 GrowableArray<DepValue>* deps = _dep_values[dept]; 337 338 // see if the same (or a similar) dep is already recorded 339 bool has_ctxk = has_explicit_context_arg(dept); 340 if (has_ctxk) { 341 assert(dep_context_arg(dept) == 0, "sanity"); 342 if (note_dep_seen(dept, x1)) { 343 // look in this bucket for redundant assertions 344 const int stride = 2; 345 for (int i = deps->length(); (i -= stride) >= 0; ) { 346 DepValue y1 = deps->at(i+1); 347 if (x1 == y1) { // same subject; check the context 348 if (maybe_merge_ctxk(deps, i+0, x0)) { 349 return; 350 } 351 } 352 } 353 } 354 } else { 355 if (note_dep_seen(dept, x0) && note_dep_seen(dept, x1)) { 356 // look in this bucket for redundant assertions 357 const int stride = 2; 358 for (int i = deps->length(); (i -= stride) >= 0; ) { 359 DepValue y0 = deps->at(i+0); 360 DepValue y1 = deps->at(i+1); 361 if (x0 == y0 && x1 == y1) { 362 return; 363 } 364 } 365 } 366 } 367 368 // append the assertion in the correct bucket: 369 deps->append(x0); 370 deps->append(x1); 371 } 372 #endif // INCLUDE_JVMCI 373 374 /// Support for encoding dependencies into an nmethod: 375 376 void Dependencies::copy_to(nmethod* nm) { 377 address beg = nm->dependencies_begin(); 378 address end = nm->dependencies_end(); 379 guarantee(end - beg >= (ptrdiff_t) size_in_bytes(), "bad sizing"); 380 Copy::disjoint_words((HeapWord*) content_bytes(), 381 (HeapWord*) beg, 382 size_in_bytes() / sizeof(HeapWord)); 383 assert(size_in_bytes() % sizeof(HeapWord) == 0, "copy by words"); 384 } 385 386 static int sort_dep(ciBaseObject** p1, ciBaseObject** p2, int narg) { 387 for (int i = 0; i < narg; i++) { 388 int diff = p1[i]->ident() - p2[i]->ident(); 389 if (diff != 0) return diff; 390 } 391 return 0; 392 } 393 static int sort_dep_arg_1(ciBaseObject** p1, ciBaseObject** p2) 394 { return sort_dep(p1, p2, 1); } 395 static int sort_dep_arg_2(ciBaseObject** p1, ciBaseObject** p2) 396 { return sort_dep(p1, p2, 2); } 397 static int sort_dep_arg_3(ciBaseObject** p1, ciBaseObject** p2) 398 { return sort_dep(p1, p2, 3); } 399 400 #if INCLUDE_JVMCI 401 // metadata deps are sorted before object deps 402 static int sort_dep_value(Dependencies::DepValue* p1, Dependencies::DepValue* p2, int narg) { 403 for (int i = 0; i < narg; i++) { 404 int diff = p1[i].sort_key() - p2[i].sort_key(); 405 if (diff != 0) return diff; 406 } 407 return 0; 408 } 409 static int sort_dep_value_arg_1(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 410 { return sort_dep_value(p1, p2, 1); } 411 static int sort_dep_value_arg_2(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 412 { return sort_dep_value(p1, p2, 2); } 413 static int sort_dep_value_arg_3(Dependencies::DepValue* p1, Dependencies::DepValue* p2) 414 { return sort_dep_value(p1, p2, 3); } 415 #endif // INCLUDE_JVMCI 416 417 void Dependencies::sort_all_deps() { 418 #if INCLUDE_JVMCI 419 if (_using_dep_values) { 420 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 421 DepType dept = (DepType)deptv; 422 GrowableArray<DepValue>* deps = _dep_values[dept]; 423 if (deps->length() <= 1) continue; 424 switch (dep_args(dept)) { 425 case 1: deps->sort(sort_dep_value_arg_1, 1); break; 426 case 2: deps->sort(sort_dep_value_arg_2, 2); break; 427 case 3: deps->sort(sort_dep_value_arg_3, 3); break; 428 default: ShouldNotReachHere(); break; 429 } 430 } 431 return; 432 } 433 #endif // INCLUDE_JVMCI 434 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 435 DepType dept = (DepType)deptv; 436 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 437 if (deps->length() <= 1) continue; 438 switch (dep_args(dept)) { 439 case 1: deps->sort(sort_dep_arg_1, 1); break; 440 case 2: deps->sort(sort_dep_arg_2, 2); break; 441 case 3: deps->sort(sort_dep_arg_3, 3); break; 442 default: ShouldNotReachHere(); break; 443 } 444 } 445 } 446 447 size_t Dependencies::estimate_size_in_bytes() { 448 size_t est_size = 100; 449 #if INCLUDE_JVMCI 450 if (_using_dep_values) { 451 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 452 DepType dept = (DepType)deptv; 453 GrowableArray<DepValue>* deps = _dep_values[dept]; 454 est_size += deps->length() * 2; // tags and argument(s) 455 } 456 return est_size; 457 } 458 #endif // INCLUDE_JVMCI 459 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 460 DepType dept = (DepType)deptv; 461 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 462 est_size += deps->length()*2; // tags and argument(s) 463 } 464 return est_size; 465 } 466 467 ciKlass* Dependencies::ctxk_encoded_as_null(DepType dept, ciBaseObject* x) { 468 switch (dept) { 469 case abstract_with_exclusive_concrete_subtypes_2: 470 return x->as_metadata()->as_klass(); 471 case unique_concrete_method: 472 case exclusive_concrete_methods_2: 473 return x->as_metadata()->as_method()->holder(); 474 default: 475 return NULL; // let NULL be NULL 476 } 477 } 478 479 Klass* Dependencies::ctxk_encoded_as_null(DepType dept, Metadata* x) { 480 assert(must_be_in_vm(), "raw oops here"); 481 switch (dept) { 482 case abstract_with_exclusive_concrete_subtypes_2: 483 assert(x->is_klass(), "sanity"); 484 return (Klass*) x; 485 case unique_concrete_method: 486 case exclusive_concrete_methods_2: 487 assert(x->is_method(), "sanity"); 488 return ((Method*)x)->method_holder(); 489 default: 490 return NULL; // let NULL be NULL 491 } 492 } 493 494 void Dependencies::encode_content_bytes() { 495 sort_all_deps(); 496 497 // cast is safe, no deps can overflow INT_MAX 498 CompressedWriteStream bytes((int)estimate_size_in_bytes()); 499 500 #if INCLUDE_JVMCI 501 if (_using_dep_values) { 502 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 503 DepType dept = (DepType)deptv; 504 GrowableArray<DepValue>* deps = _dep_values[dept]; 505 if (deps->length() == 0) continue; 506 int stride = dep_args(dept); 507 int ctxkj = dep_context_arg(dept); // -1 if no context arg 508 assert(stride > 0, "sanity"); 509 for (int i = 0; i < deps->length(); i += stride) { 510 jbyte code_byte = (jbyte)dept; 511 int skipj = -1; 512 if (ctxkj >= 0 && ctxkj+1 < stride) { 513 Klass* ctxk = deps->at(i+ctxkj+0).as_klass(_oop_recorder); 514 DepValue x = deps->at(i+ctxkj+1); // following argument 515 if (ctxk == ctxk_encoded_as_null(dept, x.as_metadata(_oop_recorder))) { 516 skipj = ctxkj; // we win: maybe one less oop to keep track of 517 code_byte |= default_context_type_bit; 518 } 519 } 520 bytes.write_byte(code_byte); 521 for (int j = 0; j < stride; j++) { 522 if (j == skipj) continue; 523 DepValue v = deps->at(i+j); 524 int idx = v.index(); 525 bytes.write_int(idx); 526 } 527 } 528 } 529 } else { 530 #endif // INCLUDE_JVMCI 531 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 532 DepType dept = (DepType)deptv; 533 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 534 if (deps->length() == 0) continue; 535 int stride = dep_args(dept); 536 int ctxkj = dep_context_arg(dept); // -1 if no context arg 537 assert(stride > 0, "sanity"); 538 for (int i = 0; i < deps->length(); i += stride) { 539 jbyte code_byte = (jbyte)dept; 540 int skipj = -1; 541 if (ctxkj >= 0 && ctxkj+1 < stride) { 542 ciKlass* ctxk = deps->at(i+ctxkj+0)->as_metadata()->as_klass(); 543 ciBaseObject* x = deps->at(i+ctxkj+1); // following argument 544 if (ctxk == ctxk_encoded_as_null(dept, x)) { 545 skipj = ctxkj; // we win: maybe one less oop to keep track of 546 code_byte |= default_context_type_bit; 547 } 548 } 549 bytes.write_byte(code_byte); 550 for (int j = 0; j < stride; j++) { 551 if (j == skipj) continue; 552 ciBaseObject* v = deps->at(i+j); 553 int idx; 554 if (v->is_object()) { 555 idx = _oop_recorder->find_index(v->as_object()->constant_encoding()); 556 } else { 557 ciMetadata* meta = v->as_metadata(); 558 idx = _oop_recorder->find_index(meta->constant_encoding()); 559 } 560 bytes.write_int(idx); 561 } 562 } 563 } 564 #if INCLUDE_JVMCI 565 } 566 #endif 567 568 // write a sentinel byte to mark the end 569 bytes.write_byte(end_marker); 570 571 // round it out to a word boundary 572 while (bytes.position() % sizeof(HeapWord) != 0) { 573 bytes.write_byte(end_marker); 574 } 575 576 // check whether the dept byte encoding really works 577 assert((jbyte)default_context_type_bit != 0, "byte overflow"); 578 579 _content_bytes = bytes.buffer(); 580 _size_in_bytes = bytes.position(); 581 } 582 583 584 const char* Dependencies::_dep_name[TYPE_LIMIT] = { 585 "end_marker", 586 "evol_method", 587 "leaf_type", 588 "abstract_with_unique_concrete_subtype", 589 "abstract_with_no_concrete_subtype", 590 "concrete_with_no_concrete_subtype", 591 "unique_concrete_method", 592 "abstract_with_exclusive_concrete_subtypes_2", 593 "exclusive_concrete_methods_2", 594 "no_finalizable_subclasses", 595 "call_site_target_value" 596 }; 597 598 int Dependencies::_dep_args[TYPE_LIMIT] = { 599 -1,// end_marker 600 1, // evol_method m 601 1, // leaf_type ctxk 602 2, // abstract_with_unique_concrete_subtype ctxk, k 603 1, // abstract_with_no_concrete_subtype ctxk 604 1, // concrete_with_no_concrete_subtype ctxk 605 2, // unique_concrete_method ctxk, m 606 3, // unique_concrete_subtypes_2 ctxk, k1, k2 607 3, // unique_concrete_methods_2 ctxk, m1, m2 608 1, // no_finalizable_subclasses ctxk 609 2 // call_site_target_value call_site, method_handle 610 }; 611 612 const char* Dependencies::dep_name(Dependencies::DepType dept) { 613 if (!dept_in_mask(dept, all_types)) return "?bad-dep?"; 614 return _dep_name[dept]; 615 } 616 617 int Dependencies::dep_args(Dependencies::DepType dept) { 618 if (!dept_in_mask(dept, all_types)) return -1; 619 return _dep_args[dept]; 620 } 621 622 void Dependencies::check_valid_dependency_type(DepType dept) { 623 guarantee(FIRST_TYPE <= dept && dept < TYPE_LIMIT, "invalid dependency type: %d", (int) dept); 624 } 625 626 Dependencies::DepType Dependencies::validate_dependencies(CompileTask* task, bool counter_changed, char** failure_detail) { 627 // First, check non-klass dependencies as we might return early and 628 // not check klass dependencies if the system dictionary 629 // modification counter hasn't changed (see below). 630 for (Dependencies::DepStream deps(this); deps.next(); ) { 631 if (deps.is_klass_type()) continue; // skip klass dependencies 632 Klass* witness = deps.check_dependency(); 633 if (witness != NULL) { 634 return deps.type(); 635 } 636 } 637 638 // Klass dependencies must be checked when the system dictionary 639 // changes. If logging is enabled all violated dependences will be 640 // recorded in the log. In debug mode check dependencies even if 641 // the system dictionary hasn't changed to verify that no invalid 642 // dependencies were inserted. Any violated dependences in this 643 // case are dumped to the tty. 644 if (!counter_changed && !trueInDebug) { 645 return end_marker; 646 } 647 648 int klass_violations = 0; 649 DepType result = end_marker; 650 for (Dependencies::DepStream deps(this); deps.next(); ) { 651 if (!deps.is_klass_type()) continue; // skip non-klass dependencies 652 Klass* witness = deps.check_dependency(); 653 if (witness != NULL) { 654 if (klass_violations == 0) { 655 result = deps.type(); 656 if (failure_detail != NULL && klass_violations == 0) { 657 // Use a fixed size buffer to prevent the string stream from 658 // resizing in the context of an inner resource mark. 659 char* buffer = NEW_RESOURCE_ARRAY(char, O_BUFLEN); 660 stringStream st(buffer, O_BUFLEN); 661 deps.print_dependency(witness, true, &st); 662 *failure_detail = st.as_string(); 663 } 664 } 665 klass_violations++; 666 if (!counter_changed) { 667 // Dependence failed but counter didn't change. Log a message 668 // describing what failed and allow the assert at the end to 669 // trigger. 670 deps.print_dependency(witness); 671 } else if (xtty == NULL) { 672 // If we're not logging then a single violation is sufficient, 673 // otherwise we want to log all the dependences which were 674 // violated. 675 break; 676 } 677 } 678 } 679 680 if (klass_violations != 0) { 681 #ifdef ASSERT 682 if (task != NULL && !counter_changed && !PrintCompilation) { 683 // Print out the compile task that failed 684 task->print_tty(); 685 } 686 #endif 687 assert(counter_changed, "failed dependencies, but counter didn't change"); 688 } 689 return result; 690 } 691 692 // for the sake of the compiler log, print out current dependencies: 693 void Dependencies::log_all_dependencies() { 694 if (log() == NULL) return; 695 ResourceMark rm; 696 for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { 697 DepType dept = (DepType)deptv; 698 GrowableArray<ciBaseObject*>* deps = _deps[dept]; 699 int deplen = deps->length(); 700 if (deplen == 0) { 701 continue; 702 } 703 int stride = dep_args(dept); 704 GrowableArray<ciBaseObject*>* ciargs = new GrowableArray<ciBaseObject*>(stride); 705 for (int i = 0; i < deps->length(); i += stride) { 706 for (int j = 0; j < stride; j++) { 707 // flush out the identities before printing 708 ciargs->push(deps->at(i+j)); 709 } 710 write_dependency_to(log(), dept, ciargs); 711 ciargs->clear(); 712 } 713 guarantee(deplen == deps->length(), "deps array cannot grow inside nested ResoureMark scope"); 714 } 715 } 716 717 void Dependencies::write_dependency_to(CompileLog* log, 718 DepType dept, 719 GrowableArray<DepArgument>* args, 720 Klass* witness) { 721 if (log == NULL) { 722 return; 723 } 724 ResourceMark rm; 725 ciEnv* env = ciEnv::current(); 726 GrowableArray<ciBaseObject*>* ciargs = new GrowableArray<ciBaseObject*>(args->length()); 727 for (GrowableArrayIterator<DepArgument> it = args->begin(); it != args->end(); ++it) { 728 DepArgument arg = *it; 729 if (arg.is_oop()) { 730 ciargs->push(env->get_object(arg.oop_value())); 731 } else { 732 ciargs->push(env->get_metadata(arg.metadata_value())); 733 } 734 } 735 int argslen = ciargs->length(); 736 Dependencies::write_dependency_to(log, dept, ciargs, witness); 737 guarantee(argslen == ciargs->length(), "ciargs array cannot grow inside nested ResoureMark scope"); 738 } 739 740 void Dependencies::write_dependency_to(CompileLog* log, 741 DepType dept, 742 GrowableArray<ciBaseObject*>* args, 743 Klass* witness) { 744 if (log == NULL) { 745 return; 746 } 747 ResourceMark rm; 748 GrowableArray<int>* argids = new GrowableArray<int>(args->length()); 749 for (GrowableArrayIterator<ciBaseObject*> it = args->begin(); it != args->end(); ++it) { 750 ciBaseObject* obj = *it; 751 if (obj->is_object()) { 752 argids->push(log->identify(obj->as_object())); 753 } else { 754 argids->push(log->identify(obj->as_metadata())); 755 } 756 } 757 if (witness != NULL) { 758 log->begin_elem("dependency_failed"); 759 } else { 760 log->begin_elem("dependency"); 761 } 762 log->print(" type='%s'", dep_name(dept)); 763 const int ctxkj = dep_context_arg(dept); // -1 if no context arg 764 if (ctxkj >= 0 && ctxkj < argids->length()) { 765 log->print(" ctxk='%d'", argids->at(ctxkj)); 766 } 767 // write remaining arguments, if any. 768 for (int j = 0; j < argids->length(); j++) { 769 if (j == ctxkj) continue; // already logged 770 if (j == 1) { 771 log->print( " x='%d'", argids->at(j)); 772 } else { 773 log->print(" x%d='%d'", j, argids->at(j)); 774 } 775 } 776 if (witness != NULL) { 777 log->object("witness", witness); 778 log->stamp(); 779 } 780 log->end_elem(); 781 } 782 783 void Dependencies::write_dependency_to(xmlStream* xtty, 784 DepType dept, 785 GrowableArray<DepArgument>* args, 786 Klass* witness) { 787 if (xtty == NULL) { 788 return; 789 } 790 Thread* thread = Thread::current(); 791 HandleMark rm(thread); 792 ttyLocker ttyl; 793 int ctxkj = dep_context_arg(dept); // -1 if no context arg 794 if (witness != NULL) { 795 xtty->begin_elem("dependency_failed"); 796 } else { 797 xtty->begin_elem("dependency"); 798 } 799 xtty->print(" type='%s'", dep_name(dept)); 800 if (ctxkj >= 0) { 801 xtty->object("ctxk", args->at(ctxkj).metadata_value()); 802 } 803 // write remaining arguments, if any. 804 for (int j = 0; j < args->length(); j++) { 805 if (j == ctxkj) continue; // already logged 806 DepArgument arg = args->at(j); 807 if (j == 1) { 808 if (arg.is_oop()) { 809 xtty->object("x", Handle(thread, arg.oop_value())); 810 } else { 811 xtty->object("x", arg.metadata_value()); 812 } 813 } else { 814 char xn[12]; sprintf(xn, "x%d", j); 815 if (arg.is_oop()) { 816 xtty->object(xn, Handle(thread, arg.oop_value())); 817 } else { 818 xtty->object(xn, arg.metadata_value()); 819 } 820 } 821 } 822 if (witness != NULL) { 823 xtty->object("witness", witness); 824 xtty->stamp(); 825 } 826 xtty->end_elem(); 827 } 828 829 void Dependencies::print_dependency(DepType dept, GrowableArray<DepArgument>* args, 830 Klass* witness, outputStream* st) { 831 ResourceMark rm; 832 ttyLocker ttyl; // keep the following output all in one block 833 st->print_cr("%s of type %s", 834 (witness == NULL)? "Dependency": "Failed dependency", 835 dep_name(dept)); 836 // print arguments 837 int ctxkj = dep_context_arg(dept); // -1 if no context arg 838 for (int j = 0; j < args->length(); j++) { 839 DepArgument arg = args->at(j); 840 bool put_star = false; 841 if (arg.is_null()) continue; 842 const char* what; 843 if (j == ctxkj) { 844 assert(arg.is_metadata(), "must be"); 845 what = "context"; 846 put_star = !Dependencies::is_concrete_klass((Klass*)arg.metadata_value()); 847 } else if (arg.is_method()) { 848 what = "method "; 849 put_star = !Dependencies::is_concrete_method((Method*)arg.metadata_value(), NULL); 850 } else if (arg.is_klass()) { 851 what = "class "; 852 } else { 853 what = "object "; 854 } 855 st->print(" %s = %s", what, (put_star? "*": "")); 856 if (arg.is_klass()) { 857 st->print("%s", ((Klass*)arg.metadata_value())->external_name()); 858 } else if (arg.is_method()) { 859 ((Method*)arg.metadata_value())->print_value_on(st); 860 } else if (arg.is_oop()) { 861 arg.oop_value()->print_value_on(st); 862 } else { 863 ShouldNotReachHere(); // Provide impl for this type. 864 } 865 866 st->cr(); 867 } 868 if (witness != NULL) { 869 bool put_star = !Dependencies::is_concrete_klass(witness); 870 st->print_cr(" witness = %s%s", 871 (put_star? "*": ""), 872 witness->external_name()); 873 } 874 } 875 876 void Dependencies::DepStream::log_dependency(Klass* witness) { 877 if (_deps == NULL && xtty == NULL) return; // fast cutout for runtime 878 ResourceMark rm; 879 const int nargs = argument_count(); 880 GrowableArray<DepArgument>* args = new GrowableArray<DepArgument>(nargs); 881 for (int j = 0; j < nargs; j++) { 882 if (is_oop_argument(j)) { 883 args->push(argument_oop(j)); 884 } else { 885 args->push(argument(j)); 886 } 887 } 888 int argslen = args->length(); 889 if (_deps != NULL && _deps->log() != NULL) { 890 if (ciEnv::current() != NULL) { 891 Dependencies::write_dependency_to(_deps->log(), type(), args, witness); 892 } else { 893 // Treat the CompileLog as an xmlstream instead 894 Dependencies::write_dependency_to((xmlStream*)_deps->log(), type(), args, witness); 895 } 896 } else { 897 Dependencies::write_dependency_to(xtty, type(), args, witness); 898 } 899 guarantee(argslen == args->length(), "args array cannot grow inside nested ResoureMark scope"); 900 } 901 902 void Dependencies::DepStream::print_dependency(Klass* witness, bool verbose, outputStream* st) { 903 ResourceMark rm; 904 int nargs = argument_count(); 905 GrowableArray<DepArgument>* args = new GrowableArray<DepArgument>(nargs); 906 for (int j = 0; j < nargs; j++) { 907 if (is_oop_argument(j)) { 908 args->push(argument_oop(j)); 909 } else { 910 args->push(argument(j)); 911 } 912 } 913 int argslen = args->length(); 914 Dependencies::print_dependency(type(), args, witness, st); 915 if (verbose) { 916 if (_code != NULL) { 917 st->print(" code: "); 918 _code->print_value_on(st); 919 st->cr(); 920 } 921 } 922 guarantee(argslen == args->length(), "args array cannot grow inside nested ResoureMark scope"); 923 } 924 925 926 /// Dependency stream support (decodes dependencies from an nmethod): 927 928 #ifdef ASSERT 929 void Dependencies::DepStream::initial_asserts(size_t byte_limit) { 930 assert(must_be_in_vm(), "raw oops here"); 931 _byte_limit = byte_limit; 932 _type = (DepType)(end_marker-1); // defeat "already at end" assert 933 assert((_code!=NULL) + (_deps!=NULL) == 1, "one or t'other"); 934 } 935 #endif //ASSERT 936 937 bool Dependencies::DepStream::next() { 938 assert(_type != end_marker, "already at end"); 939 if (_bytes.position() == 0 && _code != NULL 940 && _code->dependencies_size() == 0) { 941 // Method has no dependencies at all. 942 return false; 943 } 944 int code_byte = (_bytes.read_byte() & 0xFF); 945 if (code_byte == end_marker) { 946 DEBUG_ONLY(_type = end_marker); 947 return false; 948 } else { 949 int ctxk_bit = (code_byte & Dependencies::default_context_type_bit); 950 code_byte -= ctxk_bit; 951 DepType dept = (DepType)code_byte; 952 _type = dept; 953 Dependencies::check_valid_dependency_type(dept); 954 int stride = _dep_args[dept]; 955 assert(stride == dep_args(dept), "sanity"); 956 int skipj = -1; 957 if (ctxk_bit != 0) { 958 skipj = 0; // currently the only context argument is at zero 959 assert(skipj == dep_context_arg(dept), "zero arg always ctxk"); 960 } 961 for (int j = 0; j < stride; j++) { 962 _xi[j] = (j == skipj)? 0: _bytes.read_int(); 963 } 964 DEBUG_ONLY(_xi[stride] = -1); // help detect overruns 965 return true; 966 } 967 } 968 969 inline Metadata* Dependencies::DepStream::recorded_metadata_at(int i) { 970 Metadata* o = NULL; 971 if (_code != NULL) { 972 o = _code->metadata_at(i); 973 } else { 974 o = _deps->oop_recorder()->metadata_at(i); 975 } 976 return o; 977 } 978 979 inline oop Dependencies::DepStream::recorded_oop_at(int i) { 980 return (_code != NULL) 981 ? _code->oop_at(i) 982 : JNIHandles::resolve(_deps->oop_recorder()->oop_at(i)); 983 } 984 985 Metadata* Dependencies::DepStream::argument(int i) { 986 Metadata* result = recorded_metadata_at(argument_index(i)); 987 988 if (result == NULL) { // Explicit context argument can be compressed 989 int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg 990 if (ctxkj >= 0 && i == ctxkj && ctxkj+1 < argument_count()) { 991 result = ctxk_encoded_as_null(type(), argument(ctxkj+1)); 992 } 993 } 994 995 assert(result == NULL || result->is_klass() || result->is_method(), "must be"); 996 return result; 997 } 998 999 /** 1000 * Returns a unique identifier for each dependency argument. 1001 */ 1002 uintptr_t Dependencies::DepStream::get_identifier(int i) { 1003 if (is_oop_argument(i)) { 1004 return (uintptr_t)(oopDesc*)argument_oop(i); 1005 } else { 1006 return (uintptr_t)argument(i); 1007 } 1008 } 1009 1010 oop Dependencies::DepStream::argument_oop(int i) { 1011 oop result = recorded_oop_at(argument_index(i)); 1012 assert(oopDesc::is_oop_or_null(result), "must be"); 1013 return result; 1014 } 1015 1016 Klass* Dependencies::DepStream::context_type() { 1017 assert(must_be_in_vm(), "raw oops here"); 1018 1019 // Most dependencies have an explicit context type argument. 1020 { 1021 int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg 1022 if (ctxkj >= 0) { 1023 Metadata* k = argument(ctxkj); 1024 assert(k != NULL && k->is_klass(), "type check"); 1025 return (Klass*)k; 1026 } 1027 } 1028 1029 // Some dependencies are using the klass of the first object 1030 // argument as implicit context type. 1031 { 1032 int ctxkj = dep_implicit_context_arg(type()); 1033 if (ctxkj >= 0) { 1034 Klass* k = argument_oop(ctxkj)->klass(); 1035 assert(k != NULL && k->is_klass(), "type check"); 1036 return (Klass*) k; 1037 } 1038 } 1039 1040 // And some dependencies don't have a context type at all, 1041 // e.g. evol_method. 1042 return NULL; 1043 } 1044 1045 // ----------------- DependencySignature -------------------------------------- 1046 bool DependencySignature::equals(DependencySignature const& s1, DependencySignature const& s2) { 1047 if ((s1.type() != s2.type()) || (s1.args_count() != s2.args_count())) { 1048 return false; 1049 } 1050 1051 for (int i = 0; i < s1.args_count(); i++) { 1052 if (s1.arg(i) != s2.arg(i)) { 1053 return false; 1054 } 1055 } 1056 return true; 1057 } 1058 1059 /// Checking dependencies: 1060 1061 // This hierarchy walker inspects subtypes of a given type, 1062 // trying to find a "bad" class which breaks a dependency. 1063 // Such a class is called a "witness" to the broken dependency. 1064 // While searching around, we ignore "participants", which 1065 // are already known to the dependency. 1066 class ClassHierarchyWalker { 1067 public: 1068 enum { PARTICIPANT_LIMIT = 3 }; 1069 1070 private: 1071 // optional method descriptor to check for: 1072 Symbol* _name; 1073 Symbol* _signature; 1074 1075 // special classes which are not allowed to be witnesses: 1076 Klass* _participants[PARTICIPANT_LIMIT+1]; 1077 int _num_participants; 1078 1079 // cache of method lookups 1080 Method* _found_methods[PARTICIPANT_LIMIT+1]; 1081 1082 // if non-zero, tells how many witnesses to convert to participants 1083 int _record_witnesses; 1084 1085 void initialize(Klass* participant) { 1086 _record_witnesses = 0; 1087 _participants[0] = participant; 1088 _found_methods[0] = NULL; 1089 _num_participants = 0; 1090 if (participant != NULL) { 1091 // Terminating NULL. 1092 _participants[1] = NULL; 1093 _found_methods[1] = NULL; 1094 _num_participants = 1; 1095 } 1096 } 1097 1098 void initialize_from_method(Method* m) { 1099 assert(m != NULL && m->is_method(), "sanity"); 1100 _name = m->name(); 1101 _signature = m->signature(); 1102 } 1103 1104 public: 1105 // The walker is initialized to recognize certain methods and/or types 1106 // as friendly participants. 1107 ClassHierarchyWalker(Klass* participant, Method* m) { 1108 initialize_from_method(m); 1109 initialize(participant); 1110 } 1111 ClassHierarchyWalker(Method* m) { 1112 initialize_from_method(m); 1113 initialize(NULL); 1114 } 1115 ClassHierarchyWalker(Klass* participant = NULL) { 1116 _name = NULL; 1117 _signature = NULL; 1118 initialize(participant); 1119 } 1120 1121 // This is common code for two searches: One for concrete subtypes, 1122 // the other for concrete method implementations and overrides. 1123 bool doing_subtype_search() { 1124 return _name == NULL; 1125 } 1126 1127 int num_participants() { return _num_participants; } 1128 Klass* participant(int n) { 1129 assert((uint)n <= (uint)_num_participants, "oob"); 1130 return _participants[n]; 1131 } 1132 1133 // Note: If n==num_participants, returns NULL. 1134 Method* found_method(int n) { 1135 assert((uint)n <= (uint)_num_participants, "oob"); 1136 Method* fm = _found_methods[n]; 1137 assert(n == _num_participants || fm != NULL, "proper usage"); 1138 if (fm != NULL && fm->method_holder() != _participants[n]) { 1139 // Default methods from interfaces can be added to classes. In 1140 // that case the holder of the method is not the class but the 1141 // interface where it's defined. 1142 assert(fm->is_default_method(), "sanity"); 1143 return NULL; 1144 } 1145 return fm; 1146 } 1147 1148 #ifdef ASSERT 1149 // Assert that m is inherited into ctxk, without intervening overrides. 1150 // (May return true even if this is not true, in corner cases where we punt.) 1151 bool check_method_context(Klass* ctxk, Method* m) { 1152 if (m->method_holder() == ctxk) 1153 return true; // Quick win. 1154 if (m->is_private()) 1155 return false; // Quick lose. Should not happen. 1156 if (!(m->is_public() || m->is_protected())) 1157 // The override story is complex when packages get involved. 1158 return true; // Must punt the assertion to true. 1159 Method* lm = ctxk->lookup_method(m->name(), m->signature()); 1160 if (lm == NULL && ctxk->is_instance_klass()) { 1161 // It might be an interface method 1162 lm = InstanceKlass::cast(ctxk)->lookup_method_in_ordered_interfaces(m->name(), 1163 m->signature()); 1164 } 1165 if (lm == m) 1166 // Method m is inherited into ctxk. 1167 return true; 1168 if (lm != NULL) { 1169 if (!(lm->is_public() || lm->is_protected())) { 1170 // Method is [package-]private, so the override story is complex. 1171 return true; // Must punt the assertion to true. 1172 } 1173 if (lm->is_static()) { 1174 // Static methods don't override non-static so punt 1175 return true; 1176 } 1177 if (!Dependencies::is_concrete_method(lm, ctxk) && 1178 !Dependencies::is_concrete_method(m, ctxk)) { 1179 // They are both non-concrete 1180 if (lm->method_holder()->is_subtype_of(m->method_holder())) { 1181 // Method m is overridden by lm, but both are non-concrete. 1182 return true; 1183 } 1184 if (lm->method_holder()->is_interface() && m->method_holder()->is_interface() && 1185 ctxk->is_subtype_of(m->method_holder()) && ctxk->is_subtype_of(lm->method_holder())) { 1186 // Interface method defined in multiple super interfaces 1187 return true; 1188 } 1189 } 1190 } 1191 ResourceMark rm; 1192 tty->print_cr("Dependency method not found in the associated context:"); 1193 tty->print_cr(" context = %s", ctxk->external_name()); 1194 tty->print( " method = "); m->print_short_name(tty); tty->cr(); 1195 if (lm != NULL) { 1196 tty->print( " found = "); lm->print_short_name(tty); tty->cr(); 1197 } 1198 return false; 1199 } 1200 #endif 1201 1202 void add_participant(Klass* participant) { 1203 assert(_num_participants + _record_witnesses < PARTICIPANT_LIMIT, "oob"); 1204 int np = _num_participants++; 1205 _participants[np] = participant; 1206 _participants[np+1] = NULL; 1207 _found_methods[np+1] = NULL; 1208 } 1209 1210 void record_witnesses(int add) { 1211 if (add > PARTICIPANT_LIMIT) add = PARTICIPANT_LIMIT; 1212 assert(_num_participants + add < PARTICIPANT_LIMIT, "oob"); 1213 _record_witnesses = add; 1214 } 1215 1216 bool is_witness(Klass* k) { 1217 if (doing_subtype_search()) { 1218 return Dependencies::is_concrete_klass(k); 1219 } else if (!k->is_instance_klass()) { 1220 return false; // no methods to find in an array type 1221 } else { 1222 // Search class hierarchy first. 1223 Method* m = InstanceKlass::cast(k)->find_instance_method(_name, _signature); 1224 if (!Dependencies::is_concrete_method(m, k)) { 1225 // Check interface defaults also, if any exist. 1226 Array<Method*>* default_methods = InstanceKlass::cast(k)->default_methods(); 1227 if (default_methods == NULL) 1228 return false; 1229 m = InstanceKlass::cast(k)->find_method(default_methods, _name, _signature); 1230 if (!Dependencies::is_concrete_method(m, NULL)) 1231 return false; 1232 } 1233 _found_methods[_num_participants] = m; 1234 // Note: If add_participant(k) is called, 1235 // the method m will already be memoized for it. 1236 return true; 1237 } 1238 } 1239 1240 bool is_participant(Klass* k) { 1241 if (k == _participants[0]) { 1242 return true; 1243 } else if (_num_participants <= 1) { 1244 return false; 1245 } else { 1246 return in_list(k, &_participants[1]); 1247 } 1248 } 1249 bool ignore_witness(Klass* witness) { 1250 if (_record_witnesses == 0) { 1251 return false; 1252 } else { 1253 --_record_witnesses; 1254 add_participant(witness); 1255 return true; 1256 } 1257 } 1258 static bool in_list(Klass* x, Klass** list) { 1259 for (int i = 0; ; i++) { 1260 Klass* y = list[i]; 1261 if (y == NULL) break; 1262 if (y == x) return true; 1263 } 1264 return false; // not in list 1265 } 1266 1267 private: 1268 // the actual search method: 1269 Klass* find_witness_anywhere(Klass* context_type, 1270 bool participants_hide_witnesses, 1271 bool top_level_call = true); 1272 // the spot-checking version: 1273 Klass* find_witness_in(KlassDepChange& changes, 1274 Klass* context_type, 1275 bool participants_hide_witnesses); 1276 public: 1277 Klass* find_witness_subtype(Klass* context_type, KlassDepChange* changes = NULL) { 1278 assert(doing_subtype_search(), "must set up a subtype search"); 1279 // When looking for unexpected concrete types, 1280 // do not look beneath expected ones. 1281 const bool participants_hide_witnesses = true; 1282 // CX > CC > C' is OK, even if C' is new. 1283 // CX > { CC, C' } is not OK if C' is new, and C' is the witness. 1284 if (changes != NULL) { 1285 return find_witness_in(*changes, context_type, participants_hide_witnesses); 1286 } else { 1287 return find_witness_anywhere(context_type, participants_hide_witnesses); 1288 } 1289 } 1290 Klass* find_witness_definer(Klass* context_type, KlassDepChange* changes = NULL) { 1291 assert(!doing_subtype_search(), "must set up a method definer search"); 1292 // When looking for unexpected concrete methods, 1293 // look beneath expected ones, to see if there are overrides. 1294 const bool participants_hide_witnesses = true; 1295 // CX.m > CC.m > C'.m is not OK, if C'.m is new, and C' is the witness. 1296 if (changes != NULL) { 1297 return find_witness_in(*changes, context_type, !participants_hide_witnesses); 1298 } else { 1299 return find_witness_anywhere(context_type, !participants_hide_witnesses); 1300 } 1301 } 1302 }; 1303 1304 #ifndef PRODUCT 1305 static int deps_find_witness_calls = 0; 1306 static int deps_find_witness_steps = 0; 1307 static int deps_find_witness_recursions = 0; 1308 static int deps_find_witness_singles = 0; 1309 static int deps_find_witness_print = 0; // set to -1 to force a final print 1310 static bool count_find_witness_calls() { 1311 if (TraceDependencies || LogCompilation) { 1312 int pcount = deps_find_witness_print + 1; 1313 bool final_stats = (pcount == 0); 1314 bool initial_call = (pcount == 1); 1315 bool occasional_print = ((pcount & ((1<<10) - 1)) == 0); 1316 if (pcount < 0) pcount = 1; // crude overflow protection 1317 deps_find_witness_print = pcount; 1318 if (VerifyDependencies && initial_call) { 1319 tty->print_cr("Warning: TraceDependencies results may be inflated by VerifyDependencies"); 1320 } 1321 if (occasional_print || final_stats) { 1322 // Every now and then dump a little info about dependency searching. 1323 if (xtty != NULL) { 1324 ttyLocker ttyl; 1325 xtty->elem("deps_find_witness calls='%d' steps='%d' recursions='%d' singles='%d'", 1326 deps_find_witness_calls, 1327 deps_find_witness_steps, 1328 deps_find_witness_recursions, 1329 deps_find_witness_singles); 1330 } 1331 if (final_stats || (TraceDependencies && WizardMode)) { 1332 ttyLocker ttyl; 1333 tty->print_cr("Dependency check (find_witness) " 1334 "calls=%d, steps=%d (avg=%.1f), recursions=%d, singles=%d", 1335 deps_find_witness_calls, 1336 deps_find_witness_steps, 1337 (double)deps_find_witness_steps / deps_find_witness_calls, 1338 deps_find_witness_recursions, 1339 deps_find_witness_singles); 1340 } 1341 } 1342 return true; 1343 } 1344 return false; 1345 } 1346 #else 1347 #define count_find_witness_calls() (0) 1348 #endif //PRODUCT 1349 1350 1351 Klass* ClassHierarchyWalker::find_witness_in(KlassDepChange& changes, 1352 Klass* context_type, 1353 bool participants_hide_witnesses) { 1354 assert(changes.involves_context(context_type), "irrelevant dependency"); 1355 Klass* new_type = changes.new_type(); 1356 1357 (void)count_find_witness_calls(); 1358 NOT_PRODUCT(deps_find_witness_singles++); 1359 1360 // Current thread must be in VM (not native mode, as in CI): 1361 assert(must_be_in_vm(), "raw oops here"); 1362 // Must not move the class hierarchy during this check: 1363 assert_locked_or_safepoint(Compile_lock); 1364 1365 int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); 1366 if (nof_impls > 1) { 1367 // Avoid this case: *I.m > { A.m, C }; B.m > C 1368 // %%% Until this is fixed more systematically, bail out. 1369 // See corresponding comment in find_witness_anywhere. 1370 return context_type; 1371 } 1372 1373 assert(!is_participant(new_type), "only old classes are participants"); 1374 if (participants_hide_witnesses) { 1375 // If the new type is a subtype of a participant, we are done. 1376 for (int i = 0; i < num_participants(); i++) { 1377 Klass* part = participant(i); 1378 if (part == NULL) continue; 1379 assert(changes.involves_context(part) == new_type->is_subtype_of(part), 1380 "correct marking of participants, b/c new_type is unique"); 1381 if (changes.involves_context(part)) { 1382 // new guy is protected from this check by previous participant 1383 return NULL; 1384 } 1385 } 1386 } 1387 1388 if (is_witness(new_type) && 1389 !ignore_witness(new_type)) { 1390 return new_type; 1391 } 1392 1393 return NULL; 1394 } 1395 1396 1397 // Walk hierarchy under a context type, looking for unexpected types. 1398 // Do not report participant types, and recursively walk beneath 1399 // them only if participants_hide_witnesses is false. 1400 // If top_level_call is false, skip testing the context type, 1401 // because the caller has already considered it. 1402 Klass* ClassHierarchyWalker::find_witness_anywhere(Klass* context_type, 1403 bool participants_hide_witnesses, 1404 bool top_level_call) { 1405 // Current thread must be in VM (not native mode, as in CI): 1406 assert(must_be_in_vm(), "raw oops here"); 1407 // Must not move the class hierarchy during this check: 1408 assert_locked_or_safepoint(Compile_lock); 1409 1410 bool do_counts = count_find_witness_calls(); 1411 1412 // Check the root of the sub-hierarchy first. 1413 if (top_level_call) { 1414 if (do_counts) { 1415 NOT_PRODUCT(deps_find_witness_calls++); 1416 NOT_PRODUCT(deps_find_witness_steps++); 1417 } 1418 if (is_participant(context_type)) { 1419 if (participants_hide_witnesses) return NULL; 1420 // else fall through to search loop... 1421 } else if (is_witness(context_type) && !ignore_witness(context_type)) { 1422 // The context is an abstract class or interface, to start with. 1423 return context_type; 1424 } 1425 } 1426 1427 // Now we must check each implementor and each subclass. 1428 // Use a short worklist to avoid blowing the stack. 1429 // Each worklist entry is a *chain* of subklass siblings to process. 1430 const int CHAINMAX = 100; // >= 1 + InstanceKlass::implementors_limit 1431 Klass* chains[CHAINMAX]; 1432 int chaini = 0; // index into worklist 1433 Klass* chain; // scratch variable 1434 #define ADD_SUBCLASS_CHAIN(k) { \ 1435 assert(chaini < CHAINMAX, "oob"); \ 1436 chain = k->subklass(); \ 1437 if (chain != NULL) chains[chaini++] = chain; } 1438 1439 // Look for non-abstract subclasses. 1440 // (Note: Interfaces do not have subclasses.) 1441 ADD_SUBCLASS_CHAIN(context_type); 1442 1443 // If it is an interface, search its direct implementors. 1444 // (Their subclasses are additional indirect implementors. 1445 // See InstanceKlass::add_implementor.) 1446 // (Note: nof_implementors is always zero for non-interfaces.) 1447 if (top_level_call) { 1448 int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); 1449 if (nof_impls > 1) { 1450 // Avoid this case: *I.m > { A.m, C }; B.m > C 1451 // Here, I.m has 2 concrete implementations, but m appears unique 1452 // as A.m, because the search misses B.m when checking C. 1453 // The inherited method B.m was getting missed by the walker 1454 // when interface 'I' was the starting point. 1455 // %%% Until this is fixed more systematically, bail out. 1456 // (Old CHA had the same limitation.) 1457 return context_type; 1458 } 1459 if (nof_impls > 0) { 1460 Klass* impl = InstanceKlass::cast(context_type)->implementor(); 1461 assert(impl != NULL, "just checking"); 1462 // If impl is the same as the context_type, then more than one 1463 // implementor has seen. No exact info in this case. 1464 if (impl == context_type) { 1465 return context_type; // report an inexact witness to this sad affair 1466 } 1467 if (do_counts) 1468 { NOT_PRODUCT(deps_find_witness_steps++); } 1469 if (is_participant(impl)) { 1470 if (!participants_hide_witnesses) { 1471 ADD_SUBCLASS_CHAIN(impl); 1472 } 1473 } else if (is_witness(impl) && !ignore_witness(impl)) { 1474 return impl; 1475 } else { 1476 ADD_SUBCLASS_CHAIN(impl); 1477 } 1478 } 1479 } 1480 1481 // Recursively process each non-trivial sibling chain. 1482 while (chaini > 0) { 1483 Klass* chain = chains[--chaini]; 1484 for (Klass* sub = chain; sub != NULL; sub = sub->next_sibling()) { 1485 if (do_counts) { NOT_PRODUCT(deps_find_witness_steps++); } 1486 if (is_participant(sub)) { 1487 if (participants_hide_witnesses) continue; 1488 // else fall through to process this guy's subclasses 1489 } else if (is_witness(sub) && !ignore_witness(sub)) { 1490 return sub; 1491 } 1492 if (chaini < (VerifyDependencies? 2: CHAINMAX)) { 1493 // Fast path. (Partially disabled if VerifyDependencies.) 1494 ADD_SUBCLASS_CHAIN(sub); 1495 } else { 1496 // Worklist overflow. Do a recursive call. Should be rare. 1497 // The recursive call will have its own worklist, of course. 1498 // (Note that sub has already been tested, so that there is 1499 // no need for the recursive call to re-test. That's handy, 1500 // since the recursive call sees sub as the context_type.) 1501 if (do_counts) { NOT_PRODUCT(deps_find_witness_recursions++); } 1502 Klass* witness = find_witness_anywhere(sub, 1503 participants_hide_witnesses, 1504 /*top_level_call=*/ false); 1505 if (witness != NULL) return witness; 1506 } 1507 } 1508 } 1509 1510 // No witness found. The dependency remains unbroken. 1511 return NULL; 1512 #undef ADD_SUBCLASS_CHAIN 1513 } 1514 1515 1516 bool Dependencies::is_concrete_klass(Klass* k) { 1517 if (k->is_abstract()) return false; 1518 // %%% We could treat classes which are concrete but 1519 // have not yet been instantiated as virtually abstract. 1520 // This would require a deoptimization barrier on first instantiation. 1521 //if (k->is_not_instantiated()) return false; 1522 return true; 1523 } 1524 1525 bool Dependencies::is_concrete_method(Method* m, Klass * k) { 1526 // NULL is not a concrete method, 1527 // statics are irrelevant to virtual call sites, 1528 // abstract methods are not concrete, 1529 // overpass (error) methods are not concrete if k is abstract 1530 // 1531 // note "true" is conservative answer -- 1532 // overpass clause is false if k == NULL, implies return true if 1533 // answer depends on overpass clause. 1534 return ! ( m == NULL || m -> is_static() || m -> is_abstract() || 1535 (m->is_overpass() && k != NULL && k -> is_abstract()) ); 1536 } 1537 1538 1539 Klass* Dependencies::find_finalizable_subclass(Klass* k) { 1540 if (k->is_interface()) return NULL; 1541 if (k->has_finalizer()) return k; 1542 k = k->subklass(); 1543 while (k != NULL) { 1544 Klass* result = find_finalizable_subclass(k); 1545 if (result != NULL) return result; 1546 k = k->next_sibling(); 1547 } 1548 return NULL; 1549 } 1550 1551 1552 bool Dependencies::is_concrete_klass(ciInstanceKlass* k) { 1553 if (k->is_abstract()) return false; 1554 // We could also return false if k does not yet appear to be 1555 // instantiated, if the VM version supports this distinction also. 1556 //if (k->is_not_instantiated()) return false; 1557 return true; 1558 } 1559 1560 bool Dependencies::has_finalizable_subclass(ciInstanceKlass* k) { 1561 return k->has_finalizable_subclass(); 1562 } 1563 1564 1565 // Any use of the contents (bytecodes) of a method must be 1566 // marked by an "evol_method" dependency, if those contents 1567 // can change. (Note: A method is always dependent on itself.) 1568 Klass* Dependencies::check_evol_method(Method* m) { 1569 assert(must_be_in_vm(), "raw oops here"); 1570 // Did somebody do a JVMTI RedefineClasses while our backs were turned? 1571 // Or is there a now a breakpoint? 1572 // (Assumes compiled code cannot handle bkpts; change if UseFastBreakpoints.) 1573 if (m->is_old() 1574 || m->number_of_breakpoints() > 0) { 1575 return m->method_holder(); 1576 } else { 1577 return NULL; 1578 } 1579 } 1580 1581 // This is a strong assertion: It is that the given type 1582 // has no subtypes whatever. It is most useful for 1583 // optimizing checks on reflected types or on array types. 1584 // (Checks on types which are derived from real instances 1585 // can be optimized more strongly than this, because we 1586 // know that the checked type comes from a concrete type, 1587 // and therefore we can disregard abstract types.) 1588 Klass* Dependencies::check_leaf_type(Klass* ctxk) { 1589 assert(must_be_in_vm(), "raw oops here"); 1590 assert_locked_or_safepoint(Compile_lock); 1591 InstanceKlass* ctx = InstanceKlass::cast(ctxk); 1592 Klass* sub = ctx->subklass(); 1593 if (sub != NULL) { 1594 return sub; 1595 } else if (ctx->nof_implementors() != 0) { 1596 // if it is an interface, it must be unimplemented 1597 // (if it is not an interface, nof_implementors is always zero) 1598 Klass* impl = ctx->implementor(); 1599 assert(impl != NULL, "must be set"); 1600 return impl; 1601 } else { 1602 return NULL; 1603 } 1604 } 1605 1606 // Test the assertion that conck is the only concrete subtype* of ctxk. 1607 // The type conck itself is allowed to have have further concrete subtypes. 1608 // This allows the compiler to narrow occurrences of ctxk by conck, 1609 // when dealing with the types of actual instances. 1610 Klass* Dependencies::check_abstract_with_unique_concrete_subtype(Klass* ctxk, 1611 Klass* conck, 1612 KlassDepChange* changes) { 1613 ClassHierarchyWalker wf(conck); 1614 return wf.find_witness_subtype(ctxk, changes); 1615 } 1616 1617 // If a non-concrete class has no concrete subtypes, it is not (yet) 1618 // instantiatable. This can allow the compiler to make some paths go 1619 // dead, if they are gated by a test of the type. 1620 Klass* Dependencies::check_abstract_with_no_concrete_subtype(Klass* ctxk, 1621 KlassDepChange* changes) { 1622 // Find any concrete subtype, with no participants: 1623 ClassHierarchyWalker wf; 1624 return wf.find_witness_subtype(ctxk, changes); 1625 } 1626 1627 1628 // If a concrete class has no concrete subtypes, it can always be 1629 // exactly typed. This allows the use of a cheaper type test. 1630 Klass* Dependencies::check_concrete_with_no_concrete_subtype(Klass* ctxk, 1631 KlassDepChange* changes) { 1632 // Find any concrete subtype, with only the ctxk as participant: 1633 ClassHierarchyWalker wf(ctxk); 1634 return wf.find_witness_subtype(ctxk, changes); 1635 } 1636 1637 1638 // Find the unique concrete proper subtype of ctxk, or NULL if there 1639 // is more than one concrete proper subtype. If there are no concrete 1640 // proper subtypes, return ctxk itself, whether it is concrete or not. 1641 // The returned subtype is allowed to have have further concrete subtypes. 1642 // That is, return CC1 for CX > CC1 > CC2, but NULL for CX > { CC1, CC2 }. 1643 Klass* Dependencies::find_unique_concrete_subtype(Klass* ctxk) { 1644 ClassHierarchyWalker wf(ctxk); // Ignore ctxk when walking. 1645 wf.record_witnesses(1); // Record one other witness when walking. 1646 Klass* wit = wf.find_witness_subtype(ctxk); 1647 if (wit != NULL) return NULL; // Too many witnesses. 1648 Klass* conck = wf.participant(0); 1649 if (conck == NULL) { 1650 #ifndef PRODUCT 1651 // Make sure the dependency mechanism will pass this discovery: 1652 if (VerifyDependencies) { 1653 // Turn off dependency tracing while actually testing deps. 1654 FlagSetting fs(TraceDependencies, false); 1655 if (!Dependencies::is_concrete_klass(ctxk)) { 1656 guarantee(NULL == 1657 (void *)check_abstract_with_no_concrete_subtype(ctxk), 1658 "verify dep."); 1659 } else { 1660 guarantee(NULL == 1661 (void *)check_concrete_with_no_concrete_subtype(ctxk), 1662 "verify dep."); 1663 } 1664 } 1665 #endif //PRODUCT 1666 return ctxk; // Return ctxk as a flag for "no subtypes". 1667 } else { 1668 #ifndef PRODUCT 1669 // Make sure the dependency mechanism will pass this discovery: 1670 if (VerifyDependencies) { 1671 // Turn off dependency tracing while actually testing deps. 1672 FlagSetting fs(TraceDependencies, false); 1673 if (!Dependencies::is_concrete_klass(ctxk)) { 1674 guarantee(NULL == (void *) 1675 check_abstract_with_unique_concrete_subtype(ctxk, conck), 1676 "verify dep."); 1677 } 1678 } 1679 #endif //PRODUCT 1680 return conck; 1681 } 1682 } 1683 1684 // Test the assertion that the k[12] are the only concrete subtypes of ctxk, 1685 // except possibly for further subtypes of k[12] themselves. 1686 // The context type must be abstract. The types k1 and k2 are themselves 1687 // allowed to have further concrete subtypes. 1688 Klass* Dependencies::check_abstract_with_exclusive_concrete_subtypes( 1689 Klass* ctxk, 1690 Klass* k1, 1691 Klass* k2, 1692 KlassDepChange* changes) { 1693 ClassHierarchyWalker wf; 1694 wf.add_participant(k1); 1695 wf.add_participant(k2); 1696 return wf.find_witness_subtype(ctxk, changes); 1697 } 1698 1699 // Search ctxk for concrete implementations. If there are klen or fewer, 1700 // pack them into the given array and return the number. 1701 // Otherwise, return -1, meaning the given array would overflow. 1702 // (Note that a return of 0 means there are exactly no concrete subtypes.) 1703 // In this search, if ctxk is concrete, it will be reported alone. 1704 // For any type CC reported, no proper subtypes of CC will be reported. 1705 int Dependencies::find_exclusive_concrete_subtypes(Klass* ctxk, 1706 int klen, 1707 Klass* karray[]) { 1708 ClassHierarchyWalker wf; 1709 wf.record_witnesses(klen); 1710 Klass* wit = wf.find_witness_subtype(ctxk); 1711 if (wit != NULL) return -1; // Too many witnesses. 1712 int num = wf.num_participants(); 1713 assert(num <= klen, "oob"); 1714 // Pack the result array with the good news. 1715 for (int i = 0; i < num; i++) 1716 karray[i] = wf.participant(i); 1717 #ifndef PRODUCT 1718 // Make sure the dependency mechanism will pass this discovery: 1719 if (VerifyDependencies) { 1720 // Turn off dependency tracing while actually testing deps. 1721 FlagSetting fs(TraceDependencies, false); 1722 switch (Dependencies::is_concrete_klass(ctxk)? -1: num) { 1723 case -1: // ctxk was itself concrete 1724 guarantee(num == 1 && karray[0] == ctxk, "verify dep."); 1725 break; 1726 case 0: 1727 guarantee(NULL == (void *)check_abstract_with_no_concrete_subtype(ctxk), 1728 "verify dep."); 1729 break; 1730 case 1: 1731 guarantee(NULL == (void *) 1732 check_abstract_with_unique_concrete_subtype(ctxk, karray[0]), 1733 "verify dep."); 1734 break; 1735 case 2: 1736 guarantee(NULL == (void *) 1737 check_abstract_with_exclusive_concrete_subtypes(ctxk, 1738 karray[0], 1739 karray[1]), 1740 "verify dep."); 1741 break; 1742 default: 1743 ShouldNotReachHere(); // klen > 2 yet supported 1744 } 1745 } 1746 #endif //PRODUCT 1747 return num; 1748 } 1749 1750 // If a class (or interface) has a unique concrete method uniqm, return NULL. 1751 // Otherwise, return a class that contains an interfering method. 1752 Klass* Dependencies::check_unique_concrete_method(Klass* ctxk, Method* uniqm, 1753 KlassDepChange* changes) { 1754 // Here is a missing optimization: If uniqm->is_final(), 1755 // we don't really need to search beneath it for overrides. 1756 // This is probably not important, since we don't use dependencies 1757 // to track final methods. (They can't be "definalized".) 1758 ClassHierarchyWalker wf(uniqm->method_holder(), uniqm); 1759 return wf.find_witness_definer(ctxk, changes); 1760 } 1761 1762 // Find the set of all non-abstract methods under ctxk that match m. 1763 // (The method m must be defined or inherited in ctxk.) 1764 // Include m itself in the set, unless it is abstract. 1765 // If this set has exactly one element, return that element. 1766 Method* Dependencies::find_unique_concrete_method(Klass* ctxk, Method* m) { 1767 // Return NULL if m is marked old; must have been a redefined method. 1768 if (m->is_old()) { 1769 return NULL; 1770 } 1771 ClassHierarchyWalker wf(m); 1772 assert(wf.check_method_context(ctxk, m), "proper context"); 1773 wf.record_witnesses(1); 1774 Klass* wit = wf.find_witness_definer(ctxk); 1775 if (wit != NULL) return NULL; // Too many witnesses. 1776 Method* fm = wf.found_method(0); // Will be NULL if num_parts == 0. 1777 if (Dependencies::is_concrete_method(m, ctxk)) { 1778 if (fm == NULL) { 1779 // It turns out that m was always the only implementation. 1780 fm = m; 1781 } else if (fm != m) { 1782 // Two conflicting implementations after all. 1783 // (This can happen if m is inherited into ctxk and fm overrides it.) 1784 return NULL; 1785 } 1786 } 1787 #ifndef PRODUCT 1788 // Make sure the dependency mechanism will pass this discovery: 1789 if (VerifyDependencies && fm != NULL) { 1790 guarantee(NULL == (void *)check_unique_concrete_method(ctxk, fm), 1791 "verify dep."); 1792 } 1793 #endif //PRODUCT 1794 return fm; 1795 } 1796 1797 Klass* Dependencies::check_exclusive_concrete_methods(Klass* ctxk, 1798 Method* m1, 1799 Method* m2, 1800 KlassDepChange* changes) { 1801 ClassHierarchyWalker wf(m1); 1802 wf.add_participant(m1->method_holder()); 1803 wf.add_participant(m2->method_holder()); 1804 return wf.find_witness_definer(ctxk, changes); 1805 } 1806 1807 Klass* Dependencies::check_has_no_finalizable_subclasses(Klass* ctxk, KlassDepChange* changes) { 1808 Klass* search_at = ctxk; 1809 if (changes != NULL) 1810 search_at = changes->new_type(); // just look at the new bit 1811 return find_finalizable_subclass(search_at); 1812 } 1813 1814 Klass* Dependencies::check_call_site_target_value(oop call_site, oop method_handle, CallSiteDepChange* changes) { 1815 assert(call_site != NULL, "sanity"); 1816 assert(method_handle != NULL, "sanity"); 1817 assert(call_site->is_a(SystemDictionary::CallSite_klass()), "sanity"); 1818 1819 if (changes == NULL) { 1820 // Validate all CallSites 1821 if (java_lang_invoke_CallSite::target(call_site) != method_handle) 1822 return call_site->klass(); // assertion failed 1823 } else { 1824 // Validate the given CallSite 1825 if (call_site == changes->call_site() && java_lang_invoke_CallSite::target(call_site) != changes->method_handle()) { 1826 assert(method_handle != changes->method_handle(), "must be"); 1827 return call_site->klass(); // assertion failed 1828 } 1829 } 1830 return NULL; // assertion still valid 1831 } 1832 1833 void Dependencies::DepStream::trace_and_log_witness(Klass* witness) { 1834 if (witness != NULL) { 1835 if (TraceDependencies) { 1836 print_dependency(witness, /*verbose=*/ true); 1837 } 1838 // The following is a no-op unless logging is enabled: 1839 log_dependency(witness); 1840 } 1841 } 1842 1843 1844 Klass* Dependencies::DepStream::check_klass_dependency(KlassDepChange* changes) { 1845 assert_locked_or_safepoint(Compile_lock); 1846 Dependencies::check_valid_dependency_type(type()); 1847 1848 Klass* witness = NULL; 1849 switch (type()) { 1850 case evol_method: 1851 witness = check_evol_method(method_argument(0)); 1852 break; 1853 case leaf_type: 1854 witness = check_leaf_type(context_type()); 1855 break; 1856 case abstract_with_unique_concrete_subtype: 1857 witness = check_abstract_with_unique_concrete_subtype(context_type(), type_argument(1), changes); 1858 break; 1859 case abstract_with_no_concrete_subtype: 1860 witness = check_abstract_with_no_concrete_subtype(context_type(), changes); 1861 break; 1862 case concrete_with_no_concrete_subtype: 1863 witness = check_concrete_with_no_concrete_subtype(context_type(), changes); 1864 break; 1865 case unique_concrete_method: 1866 witness = check_unique_concrete_method(context_type(), method_argument(1), changes); 1867 break; 1868 case abstract_with_exclusive_concrete_subtypes_2: 1869 witness = check_abstract_with_exclusive_concrete_subtypes(context_type(), type_argument(1), type_argument(2), changes); 1870 break; 1871 case exclusive_concrete_methods_2: 1872 witness = check_exclusive_concrete_methods(context_type(), method_argument(1), method_argument(2), changes); 1873 break; 1874 case no_finalizable_subclasses: 1875 witness = check_has_no_finalizable_subclasses(context_type(), changes); 1876 break; 1877 default: 1878 witness = NULL; 1879 break; 1880 } 1881 trace_and_log_witness(witness); 1882 return witness; 1883 } 1884 1885 1886 Klass* Dependencies::DepStream::check_call_site_dependency(CallSiteDepChange* changes) { 1887 assert_locked_or_safepoint(Compile_lock); 1888 Dependencies::check_valid_dependency_type(type()); 1889 1890 Klass* witness = NULL; 1891 switch (type()) { 1892 case call_site_target_value: 1893 witness = check_call_site_target_value(argument_oop(0), argument_oop(1), changes); 1894 break; 1895 default: 1896 witness = NULL; 1897 break; 1898 } 1899 trace_and_log_witness(witness); 1900 return witness; 1901 } 1902 1903 1904 Klass* Dependencies::DepStream::spot_check_dependency_at(DepChange& changes) { 1905 // Handle klass dependency 1906 if (changes.is_klass_change() && changes.as_klass_change()->involves_context(context_type())) 1907 return check_klass_dependency(changes.as_klass_change()); 1908 1909 // Handle CallSite dependency 1910 if (changes.is_call_site_change()) 1911 return check_call_site_dependency(changes.as_call_site_change()); 1912 1913 // irrelevant dependency; skip it 1914 return NULL; 1915 } 1916 1917 1918 void DepChange::print() { 1919 int nsup = 0, nint = 0; 1920 for (ContextStream str(*this); str.next(); ) { 1921 Klass* k = str.klass(); 1922 switch (str.change_type()) { 1923 case Change_new_type: 1924 tty->print_cr(" dependee = %s", k->external_name()); 1925 break; 1926 case Change_new_sub: 1927 if (!WizardMode) { 1928 ++nsup; 1929 } else { 1930 tty->print_cr(" context super = %s", k->external_name()); 1931 } 1932 break; 1933 case Change_new_impl: 1934 if (!WizardMode) { 1935 ++nint; 1936 } else { 1937 tty->print_cr(" context interface = %s", k->external_name()); 1938 } 1939 break; 1940 default: 1941 break; 1942 } 1943 } 1944 if (nsup + nint != 0) { 1945 tty->print_cr(" context supers = %d, interfaces = %d", nsup, nint); 1946 } 1947 } 1948 1949 void DepChange::ContextStream::start() { 1950 Klass* new_type = _changes.is_klass_change() ? _changes.as_klass_change()->new_type() : (Klass*) NULL; 1951 _change_type = (new_type == NULL ? NO_CHANGE : Start_Klass); 1952 _klass = new_type; 1953 _ti_base = NULL; 1954 _ti_index = 0; 1955 _ti_limit = 0; 1956 } 1957 1958 bool DepChange::ContextStream::next() { 1959 switch (_change_type) { 1960 case Start_Klass: // initial state; _klass is the new type 1961 _ti_base = InstanceKlass::cast(_klass)->transitive_interfaces(); 1962 _ti_index = 0; 1963 _change_type = Change_new_type; 1964 return true; 1965 case Change_new_type: 1966 // fall through: 1967 _change_type = Change_new_sub; 1968 case Change_new_sub: 1969 // 6598190: brackets workaround Sun Studio C++ compiler bug 6629277 1970 { 1971 _klass = _klass->super(); 1972 if (_klass != NULL) { 1973 return true; 1974 } 1975 } 1976 // else set up _ti_limit and fall through: 1977 _ti_limit = (_ti_base == NULL) ? 0 : _ti_base->length(); 1978 _change_type = Change_new_impl; 1979 case Change_new_impl: 1980 if (_ti_index < _ti_limit) { 1981 _klass = _ti_base->at(_ti_index++); 1982 return true; 1983 } 1984 // fall through: 1985 _change_type = NO_CHANGE; // iterator is exhausted 1986 case NO_CHANGE: 1987 break; 1988 default: 1989 ShouldNotReachHere(); 1990 } 1991 return false; 1992 } 1993 1994 void KlassDepChange::initialize() { 1995 // entire transaction must be under this lock: 1996 assert_lock_strong(Compile_lock); 1997 1998 // Mark all dependee and all its superclasses 1999 // Mark transitive interfaces 2000 for (ContextStream str(*this); str.next(); ) { 2001 Klass* d = str.klass(); 2002 assert(!InstanceKlass::cast(d)->is_marked_dependent(), "checking"); 2003 InstanceKlass::cast(d)->set_is_marked_dependent(true); 2004 } 2005 } 2006 2007 KlassDepChange::~KlassDepChange() { 2008 // Unmark all dependee and all its superclasses 2009 // Unmark transitive interfaces 2010 for (ContextStream str(*this); str.next(); ) { 2011 Klass* d = str.klass(); 2012 InstanceKlass::cast(d)->set_is_marked_dependent(false); 2013 } 2014 } 2015 2016 bool KlassDepChange::involves_context(Klass* k) { 2017 if (k == NULL || !k->is_instance_klass()) { 2018 return false; 2019 } 2020 InstanceKlass* ik = InstanceKlass::cast(k); 2021 bool is_contained = ik->is_marked_dependent(); 2022 assert(is_contained == new_type()->is_subtype_of(k), 2023 "correct marking of potential context types"); 2024 return is_contained; 2025 } 2026 2027 #ifndef PRODUCT 2028 void Dependencies::print_statistics() { 2029 if (deps_find_witness_print != 0) { 2030 // Call one final time, to flush out the data. 2031 deps_find_witness_print = -1; 2032 count_find_witness_calls(); 2033 } 2034 } 2035 #endif 2036 2037 CallSiteDepChange::CallSiteDepChange(Handle call_site, Handle method_handle) : 2038 _call_site(call_site), 2039 _method_handle(method_handle) { 2040 assert(_call_site()->is_a(SystemDictionary::CallSite_klass()), "must be"); 2041 assert(_method_handle.is_null() || _method_handle()->is_a(SystemDictionary::MethodHandle_klass()), "must be"); 2042 }