frame.cpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1997, 2010, 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 "incls/_precompiled.incl" 26# include "incls/_frame.cpp.incl" 27 28RegisterMap::RegisterMap(JavaThread *thread, bool update_map) { 29 _thread = thread; 30 _update_map = update_map; 31 clear(); 32 debug_only(_update_for_id = NULL;) 33#ifndef PRODUCT 34 for (int i = 0; i < reg_count ; i++ ) _location[i] = NULL; 35#endif /* PRODUCT */ 36} 37 38RegisterMap::RegisterMap(const RegisterMap* map) { 39 assert(map != this, "bad initialization parameter"); 40 assert(map != NULL, "RegisterMap must be present"); 41 _thread = map->thread(); 42 _update_map = map->update_map(); 43 _include_argument_oops = map->include_argument_oops(); 44 debug_only(_update_for_id = map->_update_for_id;) 45 pd_initialize_from(map); 46 if (update_map()) { 47 for(int i = 0; i < location_valid_size; i++) { 48 LocationValidType bits = !update_map() ? 0 : map->_location_valid[i]; 49 _location_valid[i] = bits; 50 // for whichever bits are set, pull in the corresponding map->_location 51 int j = i*location_valid_type_size; 52 while (bits != 0) { 53 if ((bits & 1) != 0) { 54 assert(0 <= j && j < reg_count, "range check"); 55 _location[j] = map->_location[j]; 56 } 57 bits >>= 1; 58 j += 1; 59 } 60 } 61 } 62} 63 64void RegisterMap::clear() { 65 set_include_argument_oops(true); 66 if (_update_map) { 67 for(int i = 0; i < location_valid_size; i++) { 68 _location_valid[i] = 0; 69 } 70 pd_clear(); 71 } else { 72 pd_initialize(); 73 } 74} 75 76#ifndef PRODUCT 77 78void RegisterMap::print_on(outputStream* st) const { 79 st->print_cr("Register map"); 80 for(int i = 0; i < reg_count; i++) { 81 82 VMReg r = VMRegImpl::as_VMReg(i); 83 intptr_t* src = (intptr_t*) location(r); 84 if (src != NULL) { 85 86 r->print_on(st); 87 st->print(" [" INTPTR_FORMAT "] = ", src); 88 if (((uintptr_t)src & (sizeof(*src)-1)) != 0) { 89 st->print_cr("<misaligned>"); 90 } else { 91 st->print_cr(INTPTR_FORMAT, *src); 92 } 93 } 94 } 95} 96 97void RegisterMap::print() const { 98 print_on(tty); 99} 100 101#endif 102// This returns the pc that if you were in the debugger you'd see. Not 103// the idealized value in the frame object. This undoes the magic conversion 104// that happens for deoptimized frames. In addition it makes the value the 105// hardware would want to see in the native frame. The only user (at this point) 106// is deoptimization. It likely no one else should ever use it. 107 108address frame::raw_pc() const { 109 if (is_deoptimized_frame()) { 110 nmethod* nm = cb()->as_nmethod_or_null(); 111 if (nm->is_method_handle_return(pc())) 112 return nm->deopt_mh_handler_begin() - pc_return_offset; 113 else 114 return nm->deopt_handler_begin() - pc_return_offset; 115 } else { 116 return (pc() - pc_return_offset); 117 } 118} 119 120// Change the pc in a frame object. This does not change the actual pc in 121// actual frame. To do that use patch_pc. 122// 123void frame::set_pc(address newpc ) { 124#ifdef ASSERT 125 if (_cb != NULL && _cb->is_nmethod()) { 126 assert(!((nmethod*)_cb)->is_deopt_pc(_pc), "invariant violation"); 127 } 128#endif // ASSERT 129 130 // Unsafe to use the is_deoptimzed tester after changing pc 131 _deopt_state = unknown; 132 _pc = newpc; 133 _cb = CodeCache::find_blob_unsafe(_pc); 134 135} 136 137// type testers 138bool frame::is_deoptimized_frame() const { 139 assert(_deopt_state != unknown, "not answerable"); 140 return _deopt_state == is_deoptimized; 141} 142 143bool frame::is_native_frame() const { 144 return (_cb != NULL && 145 _cb->is_nmethod() && 146 ((nmethod*)_cb)->is_native_method()); 147} 148 149bool frame::is_java_frame() const { 150 if (is_interpreted_frame()) return true; 151 if (is_compiled_frame()) return true; 152 return false; 153} 154 155 156bool frame::is_compiled_frame() const { 157 if (_cb != NULL && 158 _cb->is_nmethod() && 159 ((nmethod*)_cb)->is_java_method()) { 160 return true; 161 } 162 return false; 163} 164 165 166bool frame::is_runtime_frame() const { 167 return (_cb != NULL && _cb->is_runtime_stub()); 168} 169 170bool frame::is_safepoint_blob_frame() const { 171 return (_cb != NULL && _cb->is_safepoint_stub()); 172} 173 174// testers 175 176bool frame::is_first_java_frame() const { 177 RegisterMap map(JavaThread::current(), false); // No update 178 frame s; 179 for (s = sender(&map); !(s.is_java_frame() || s.is_first_frame()); s = s.sender(&map)); 180 return s.is_first_frame(); 181} 182 183 184bool frame::entry_frame_is_first() const { 185 return entry_frame_call_wrapper()->anchor()->last_Java_sp() == NULL; 186} 187 188 189bool frame::should_be_deoptimized() const { 190 if (_deopt_state == is_deoptimized || 191 !is_compiled_frame() ) return false; 192 assert(_cb != NULL && _cb->is_nmethod(), "must be an nmethod"); 193 nmethod* nm = (nmethod *)_cb; 194 if (TraceDependencies) { 195 tty->print("checking (%s) ", nm->is_marked_for_deoptimization() ? "true" : "false"); 196 nm->print_value_on(tty); 197 tty->cr(); 198 } 199 200 if( !nm->is_marked_for_deoptimization() ) 201 return false; 202 203 // If at the return point, then the frame has already been popped, and 204 // only the return needs to be executed. Don't deoptimize here. 205 return !nm->is_at_poll_return(pc()); 206} 207 208bool frame::can_be_deoptimized() const { 209 if (!is_compiled_frame()) return false; 210 nmethod* nm = (nmethod*)_cb; 211 212 if( !nm->can_be_deoptimized() ) 213 return false; 214 215 return !nm->is_at_poll_return(pc()); 216} 217 218void frame::deoptimize(JavaThread* thread, bool thread_is_known_safe) { 219// Schedule deoptimization of an nmethod activation with this frame. 220 221 // Store the original pc before an patch (or request to self-deopt) 222 // in the published location of the frame. 223 224 assert(_cb != NULL && _cb->is_nmethod(), "must be"); 225 nmethod* nm = (nmethod*)_cb; 226 227 // This is a fix for register window patching race 228 if (NeedsDeoptSuspend && !thread_is_known_safe) { 229 230 // It is possible especially with DeoptimizeALot/DeoptimizeRandom that 231 // we could see the frame again and ask for it to be deoptimized since 232 // it might move for a long time. That is harmless and we just ignore it. 233 if (id() == thread->must_deopt_id()) { 234 assert(thread->is_deopt_suspend(), "lost suspension"); 235 return; 236 } 237 238 // We are at a safepoint so the target thread can only be 239 // in 4 states: 240 // blocked - no problem 241 // blocked_trans - no problem (i.e. could have woken up from blocked 242 // during a safepoint). 243 // native - register window pc patching race 244 // native_trans - momentary state 245 // 246 // We could just wait out a thread in native_trans to block. 247 // Then we'd have all the issues that the safepoint code has as to 248 // whether to spin or block. It isn't worth it. Just treat it like 249 // native and be done with it. 250 // 251 JavaThreadState state = thread->thread_state(); 252 if (state == _thread_in_native || state == _thread_in_native_trans) { 253 // Since we are at a safepoint the target thread will stop itself 254 // before it can return to java as long as we remain at the safepoint. 255 // Therefore we can put an additional request for the thread to stop 256 // no matter what no (like a suspend). This will cause the thread 257 // to notice it needs to do the deopt on its own once it leaves native. 258 // 259 // The only reason we must do this is because on machine with register 260 // windows we have a race with patching the return address and the 261 // window coming live as the thread returns to the Java code (but still 262 // in native mode) and then blocks. It is only this top most frame 263 // that is at risk. So in truth we could add an additional check to 264 // see if this frame is one that is at risk. 265 RegisterMap map(thread, false); 266 frame at_risk = thread->last_frame().sender(&map); 267 if (id() == at_risk.id()) { 268 thread->set_must_deopt_id(id()); 269 thread->set_deopt_suspend(); 270 return; 271 } 272 } 273 } // NeedsDeoptSuspend 274 275 276 // If the call site is a MethodHandle call site use the MH deopt 277 // handler. 278 address deopt = nm->is_method_handle_return(pc()) ? 279 nm->deopt_mh_handler_begin() : 280 nm->deopt_handler_begin(); 281 282 // Save the original pc before we patch in the new one 283 nm->set_original_pc(this, pc()); 284 patch_pc(thread, deopt); 285 286#ifdef ASSERT 287 { 288 RegisterMap map(thread, false); 289 frame check = thread->last_frame(); 290 while (id() != check.id()) { 291 check = check.sender(&map); 292 } 293 assert(check.is_deoptimized_frame(), "missed deopt"); 294 } 295#endif // ASSERT 296} 297 298frame frame::java_sender() const { 299 RegisterMap map(JavaThread::current(), false); 300 frame s; 301 for (s = sender(&map); !(s.is_java_frame() || s.is_first_frame()); s = s.sender(&map)) ; 302 guarantee(s.is_java_frame(), "tried to get caller of first java frame"); 303 return s; 304} 305 306frame frame::real_sender(RegisterMap* map) const { 307 frame result = sender(map); 308 while (result.is_runtime_frame()) { 309 result = result.sender(map); 310 } 311 return result; 312} 313 314// Note: called by profiler - NOT for current thread 315frame frame::profile_find_Java_sender_frame(JavaThread *thread) { 316// If we don't recognize this frame, walk back up the stack until we do 317 RegisterMap map(thread, false); 318 frame first_java_frame = frame(); 319 320 // Find the first Java frame on the stack starting with input frame 321 if (is_java_frame()) { 322 // top frame is compiled frame or deoptimized frame 323 first_java_frame = *this; 324 } else if (safe_for_sender(thread)) { 325 for (frame sender_frame = sender(&map); 326 sender_frame.safe_for_sender(thread) && !sender_frame.is_first_frame(); 327 sender_frame = sender_frame.sender(&map)) { 328 if (sender_frame.is_java_frame()) { 329 first_java_frame = sender_frame; 330 break; 331 } 332 } 333 } 334 return first_java_frame; 335} 336 337// Interpreter frames 338 339 340void frame::interpreter_frame_set_locals(intptr_t* locs) { 341 assert(is_interpreted_frame(), "Not an interpreted frame"); 342 *interpreter_frame_locals_addr() = locs; 343} 344 345methodOop frame::interpreter_frame_method() const { 346 assert(is_interpreted_frame(), "interpreted frame expected"); 347 methodOop m = *interpreter_frame_method_addr(); 348 assert(m->is_perm(), "bad methodOop in interpreter frame"); 349 assert(m->is_method(), "not a methodOop"); 350 return m; 351} 352 353void frame::interpreter_frame_set_method(methodOop method) { 354 assert(is_interpreted_frame(), "interpreted frame expected"); 355 *interpreter_frame_method_addr() = method; 356} 357 358void frame::interpreter_frame_set_bcx(intptr_t bcx) { 359 assert(is_interpreted_frame(), "Not an interpreted frame"); 360 if (ProfileInterpreter) { 361 bool formerly_bci = is_bci(interpreter_frame_bcx()); 362 bool is_now_bci = is_bci(bcx); 363 *interpreter_frame_bcx_addr() = bcx; 364 365 intptr_t mdx = interpreter_frame_mdx(); 366 367 if (mdx != 0) { 368 if (formerly_bci) { 369 if (!is_now_bci) { 370 // The bcx was just converted from bci to bcp. 371 // Convert the mdx in parallel. 372 methodDataOop mdo = interpreter_frame_method()->method_data(); 373 assert(mdo != NULL, ""); 374 int mdi = mdx - 1; // We distinguish valid mdi from zero by adding one. 375 address mdp = mdo->di_to_dp(mdi); 376 interpreter_frame_set_mdx((intptr_t)mdp); 377 } 378 } else { 379 if (is_now_bci) { 380 // The bcx was just converted from bcp to bci. 381 // Convert the mdx in parallel. 382 methodDataOop mdo = interpreter_frame_method()->method_data(); 383 assert(mdo != NULL, ""); 384 int mdi = mdo->dp_to_di((address)mdx); 385 interpreter_frame_set_mdx((intptr_t)mdi + 1); // distinguish valid from 0. 386 } 387 } 388 } 389 } else { 390 *interpreter_frame_bcx_addr() = bcx; 391 } 392} 393 394jint frame::interpreter_frame_bci() const { 395 assert(is_interpreted_frame(), "interpreted frame expected"); 396 intptr_t bcx = interpreter_frame_bcx(); 397 return is_bci(bcx) ? bcx : interpreter_frame_method()->bci_from((address)bcx); 398} 399 400void frame::interpreter_frame_set_bci(jint bci) { 401 assert(is_interpreted_frame(), "interpreted frame expected"); 402 assert(!is_bci(interpreter_frame_bcx()), "should not set bci during GC"); 403 interpreter_frame_set_bcx((intptr_t)interpreter_frame_method()->bcp_from(bci)); 404} 405 406address frame::interpreter_frame_bcp() const { 407 assert(is_interpreted_frame(), "interpreted frame expected"); 408 intptr_t bcx = interpreter_frame_bcx(); 409 return is_bci(bcx) ? interpreter_frame_method()->bcp_from(bcx) : (address)bcx; 410} 411 412void frame::interpreter_frame_set_bcp(address bcp) { 413 assert(is_interpreted_frame(), "interpreted frame expected"); 414 assert(!is_bci(interpreter_frame_bcx()), "should not set bcp during GC"); 415 interpreter_frame_set_bcx((intptr_t)bcp); 416} 417 418void frame::interpreter_frame_set_mdx(intptr_t mdx) { 419 assert(is_interpreted_frame(), "Not an interpreted frame"); 420 assert(ProfileInterpreter, "must be profiling interpreter"); 421 *interpreter_frame_mdx_addr() = mdx; 422} 423 424address frame::interpreter_frame_mdp() const { 425 assert(ProfileInterpreter, "must be profiling interpreter"); 426 assert(is_interpreted_frame(), "interpreted frame expected"); 427 intptr_t bcx = interpreter_frame_bcx(); 428 intptr_t mdx = interpreter_frame_mdx(); 429 430 assert(!is_bci(bcx), "should not access mdp during GC"); 431 return (address)mdx; 432} 433 434void frame::interpreter_frame_set_mdp(address mdp) { 435 assert(is_interpreted_frame(), "interpreted frame expected"); 436 if (mdp == NULL) { 437 // Always allow the mdp to be cleared. 438 interpreter_frame_set_mdx((intptr_t)mdp); 439 } 440 intptr_t bcx = interpreter_frame_bcx(); 441 assert(!is_bci(bcx), "should not set mdp during GC"); 442 interpreter_frame_set_mdx((intptr_t)mdp); 443} 444 445BasicObjectLock* frame::next_monitor_in_interpreter_frame(BasicObjectLock* current) const { 446 assert(is_interpreted_frame(), "Not an interpreted frame"); 447#ifdef ASSERT 448 interpreter_frame_verify_monitor(current); 449#endif 450 BasicObjectLock* next = (BasicObjectLock*) (((intptr_t*) current) + interpreter_frame_monitor_size()); 451 return next; 452} 453 454BasicObjectLock* frame::previous_monitor_in_interpreter_frame(BasicObjectLock* current) const { 455 assert(is_interpreted_frame(), "Not an interpreted frame"); 456#ifdef ASSERT 457// // This verification needs to be checked before being enabled 458// interpreter_frame_verify_monitor(current); 459#endif 460 BasicObjectLock* previous = (BasicObjectLock*) (((intptr_t*) current) - interpreter_frame_monitor_size()); 461 return previous; 462} 463 464// Interpreter locals and expression stack locations. 465 466intptr_t* frame::interpreter_frame_local_at(int index) const { 467 const int n = Interpreter::local_offset_in_bytes(index)/wordSize; 468 return &((*interpreter_frame_locals_addr())[n]); 469} 470 471intptr_t* frame::interpreter_frame_expression_stack_at(jint offset) const { 472 const int i = offset * interpreter_frame_expression_stack_direction(); 473 const int n = i * Interpreter::stackElementWords; 474 return &(interpreter_frame_expression_stack()[n]); 475} 476 477jint frame::interpreter_frame_expression_stack_size() const { 478 // Number of elements on the interpreter expression stack 479 // Callers should span by stackElementWords 480 int element_size = Interpreter::stackElementWords; 481 if (frame::interpreter_frame_expression_stack_direction() < 0) { 482 return (interpreter_frame_expression_stack() - 483 interpreter_frame_tos_address() + 1)/element_size; 484 } else { 485 return (interpreter_frame_tos_address() - 486 interpreter_frame_expression_stack() + 1)/element_size; 487 } 488} 489 490 491// (frame::interpreter_frame_sender_sp accessor is in frame_<arch>.cpp) 492 493const char* frame::print_name() const { 494 if (is_native_frame()) return "Native"; 495 if (is_interpreted_frame()) return "Interpreted"; 496 if (is_compiled_frame()) { 497 if (is_deoptimized_frame()) return "Deoptimized"; 498 return "Compiled"; 499 } 500 if (sp() == NULL) return "Empty"; 501 return "C"; 502} 503 504void frame::print_value_on(outputStream* st, JavaThread *thread) const { 505 NOT_PRODUCT(address begin = pc()-40;) 506 NOT_PRODUCT(address end = NULL;) 507 508 st->print("%s frame (sp=" INTPTR_FORMAT " unextended sp=" INTPTR_FORMAT, print_name(), sp(), unextended_sp()); 509 if (sp() != NULL) 510 st->print(", fp=" INTPTR_FORMAT ", pc=" INTPTR_FORMAT, fp(), pc()); 511 512 if (StubRoutines::contains(pc())) { 513 st->print_cr(")"); 514 st->print("("); 515 StubCodeDesc* desc = StubCodeDesc::desc_for(pc()); 516 st->print("~Stub::%s", desc->name()); 517 NOT_PRODUCT(begin = desc->begin(); end = desc->end();) 518 } else if (Interpreter::contains(pc())) { 519 st->print_cr(")"); 520 st->print("("); 521 InterpreterCodelet* desc = Interpreter::codelet_containing(pc()); 522 if (desc != NULL) { 523 st->print("~"); 524 desc->print(); 525 NOT_PRODUCT(begin = desc->code_begin(); end = desc->code_end();) 526 } else { 527 st->print("~interpreter"); 528 } 529 } 530 st->print_cr(")"); 531 532 if (_cb != NULL) { 533 st->print(" "); 534 _cb->print_value_on(st); 535 st->cr(); 536#ifndef PRODUCT 537 if (end == NULL) { 538 begin = _cb->instructions_begin(); 539 end = _cb->instructions_end(); 540 } 541#endif 542 } 543 NOT_PRODUCT(if (WizardMode && Verbose) Disassembler::decode(begin, end);) 544} 545 546 547void frame::print_on(outputStream* st) const { 548 print_value_on(st,NULL); 549 if (is_interpreted_frame()) { 550 interpreter_frame_print_on(st); 551 } 552} 553 554 555void frame::interpreter_frame_print_on(outputStream* st) const { 556#ifndef PRODUCT 557 assert(is_interpreted_frame(), "Not an interpreted frame"); 558 jint i; 559 for (i = 0; i < interpreter_frame_method()->max_locals(); i++ ) { 560 intptr_t x = *interpreter_frame_local_at(i); 561 st->print(" - local [" INTPTR_FORMAT "]", x); 562 st->fill_to(23); 563 st->print_cr("; #%d", i); 564 } 565 for (i = interpreter_frame_expression_stack_size() - 1; i >= 0; --i ) { 566 intptr_t x = *interpreter_frame_expression_stack_at(i); 567 st->print(" - stack [" INTPTR_FORMAT "]", x); 568 st->fill_to(23); 569 st->print_cr("; #%d", i); 570 } 571 // locks for synchronization 572 for (BasicObjectLock* current = interpreter_frame_monitor_end(); 573 current < interpreter_frame_monitor_begin(); 574 current = next_monitor_in_interpreter_frame(current)) { 575 st->print(" - obj ["); 576 current->obj()->print_value_on(st); 577 st->print_cr("]"); 578 st->print(" - lock ["); 579 current->lock()->print_on(st); 580 st->print_cr("]"); 581 } 582 // monitor 583 st->print_cr(" - monitor[" INTPTR_FORMAT "]", interpreter_frame_monitor_begin()); 584 // bcp 585 st->print(" - bcp [" INTPTR_FORMAT "]", interpreter_frame_bcp()); 586 st->fill_to(23); 587 st->print_cr("; @%d", interpreter_frame_bci()); 588 // locals 589 st->print_cr(" - locals [" INTPTR_FORMAT "]", interpreter_frame_local_at(0)); 590 // method 591 st->print(" - method [" INTPTR_FORMAT "]", (address)interpreter_frame_method()); 592 st->fill_to(23); 593 st->print("; "); 594 interpreter_frame_method()->print_name(st); 595 st->cr(); 596#endif 597} 598 599// Return whether the frame is in the VM or os indicating a Hotspot problem. 600// Otherwise, it's likely a bug in the native library that the Java code calls, 601// hopefully indicating where to submit bugs. 602static void print_C_frame(outputStream* st, char* buf, int buflen, address pc) { 603 // C/C++ frame 604 bool in_vm = os::address_is_in_vm(pc); 605 st->print(in_vm ? "V" : "C"); 606 607 int offset; 608 bool found; 609 610 // libname 611 found = os::dll_address_to_library_name(pc, buf, buflen, &offset); 612 if (found) { 613 // skip directory names 614 const char *p1, *p2; 615 p1 = buf; 616 int len = (int)strlen(os::file_separator()); 617 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len; 618 st->print(" [%s+0x%x]", p1, offset); 619 } else { 620 st->print(" " PTR_FORMAT, pc); 621 } 622 623 // function name - os::dll_address_to_function_name() may return confusing 624 // names if pc is within jvm.dll or libjvm.so, because JVM only has 625 // JVM_xxxx and a few other symbols in the dynamic symbol table. Do this 626 // only for native libraries. 627 if (!in_vm) { 628 found = os::dll_address_to_function_name(pc, buf, buflen, &offset); 629 630 if (found) { 631 st->print(" %s+0x%x", buf, offset); 632 } 633 } 634} 635 636// frame::print_on_error() is called by fatal error handler. Notice that we may 637// crash inside this function if stack frame is corrupted. The fatal error 638// handler can catch and handle the crash. Here we assume the frame is valid. 639// 640// First letter indicates type of the frame: 641// J: Java frame (compiled) 642// j: Java frame (interpreted) 643// V: VM frame (C/C++) 644// v: Other frames running VM generated code (e.g. stubs, adapters, etc.) 645// C: C/C++ frame 646// 647// We don't need detailed frame type as that in frame::print_name(). "C" 648// suggests the problem is in user lib; everything else is likely a VM bug. 649 650void frame::print_on_error(outputStream* st, char* buf, int buflen, bool verbose) const { 651 if (_cb != NULL) { 652 if (Interpreter::contains(pc())) { 653 methodOop m = this->interpreter_frame_method(); 654 if (m != NULL) { 655 m->name_and_sig_as_C_string(buf, buflen); 656 st->print("j %s", buf); 657 st->print("+%d", this->interpreter_frame_bci()); 658 } else { 659 st->print("j " PTR_FORMAT, pc()); 660 } 661 } else if (StubRoutines::contains(pc())) { 662 StubCodeDesc* desc = StubCodeDesc::desc_for(pc()); 663 if (desc != NULL) { 664 st->print("v ~StubRoutines::%s", desc->name()); 665 } else { 666 st->print("v ~StubRoutines::" PTR_FORMAT, pc()); 667 } 668 } else if (_cb->is_buffer_blob()) { 669 st->print("v ~BufferBlob::%s", ((BufferBlob *)_cb)->name()); 670 } else if (_cb->is_nmethod()) { 671 methodOop m = ((nmethod *)_cb)->method(); 672 if (m != NULL) { 673 m->name_and_sig_as_C_string(buf, buflen); 674 st->print("J %s", buf); 675 } else { 676 st->print("J " PTR_FORMAT, pc()); 677 } 678 } else if (_cb->is_runtime_stub()) { 679 st->print("v ~RuntimeStub::%s", ((RuntimeStub *)_cb)->name()); 680 } else if (_cb->is_deoptimization_stub()) { 681 st->print("v ~DeoptimizationBlob"); 682 } else if (_cb->is_exception_stub()) { 683 st->print("v ~ExceptionBlob"); 684 } else if (_cb->is_safepoint_stub()) { 685 st->print("v ~SafepointBlob"); 686 } else { 687 st->print("v blob " PTR_FORMAT, pc()); 688 } 689 } else { 690 print_C_frame(st, buf, buflen, pc()); 691 } 692} 693 694 695/* 696 The interpreter_frame_expression_stack_at method in the case of SPARC needs the 697 max_stack value of the method in order to compute the expression stack address. 698 It uses the methodOop in order to get the max_stack value but during GC this 699 methodOop value saved on the frame is changed by reverse_and_push and hence cannot 700 be used. So we save the max_stack value in the FrameClosure object and pass it 701 down to the interpreter_frame_expression_stack_at method 702*/ 703class InterpreterFrameClosure : public OffsetClosure { 704 private: 705 frame* _fr; 706 OopClosure* _f; 707 int _max_locals; 708 int _max_stack; 709 710 public: 711 InterpreterFrameClosure(frame* fr, int max_locals, int max_stack, 712 OopClosure* f) { 713 _fr = fr; 714 _max_locals = max_locals; 715 _max_stack = max_stack; 716 _f = f; 717 } 718 719 void offset_do(int offset) { 720 oop* addr; 721 if (offset < _max_locals) { 722 addr = (oop*) _fr->interpreter_frame_local_at(offset); 723 assert((intptr_t*)addr >= _fr->sp(), "must be inside the frame"); 724 _f->do_oop(addr); 725 } else { 726 addr = (oop*) _fr->interpreter_frame_expression_stack_at((offset - _max_locals)); 727 // In case of exceptions, the expression stack is invalid and the esp will be reset to express 728 // this condition. Therefore, we call f only if addr is 'inside' the stack (i.e., addr >= esp for Intel). 729 bool in_stack; 730 if (frame::interpreter_frame_expression_stack_direction() > 0) { 731 in_stack = (intptr_t*)addr <= _fr->interpreter_frame_tos_address(); 732 } else { 733 in_stack = (intptr_t*)addr >= _fr->interpreter_frame_tos_address(); 734 } 735 if (in_stack) { 736 _f->do_oop(addr); 737 } 738 } 739 } 740 741 int max_locals() { return _max_locals; } 742 frame* fr() { return _fr; } 743}; 744 745 746class InterpretedArgumentOopFinder: public SignatureInfo { 747 private: 748 OopClosure* _f; // Closure to invoke 749 int _offset; // TOS-relative offset, decremented with each argument 750 bool _has_receiver; // true if the callee has a receiver 751 frame* _fr; 752 753 void set(int size, BasicType type) { 754 _offset -= size; 755 if (type == T_OBJECT || type == T_ARRAY) oop_offset_do(); 756 } 757 758 void oop_offset_do() { 759 oop* addr; 760 addr = (oop*)_fr->interpreter_frame_tos_at(_offset); 761 _f->do_oop(addr); 762 } 763 764 public: 765 InterpretedArgumentOopFinder(symbolHandle signature, bool has_receiver, frame* fr, OopClosure* f) : SignatureInfo(signature), _has_receiver(has_receiver) { 766 // compute size of arguments 767 int args_size = ArgumentSizeComputer(signature).size() + (has_receiver ? 1 : 0); 768 assert(!fr->is_interpreted_frame() || 769 args_size <= fr->interpreter_frame_expression_stack_size(), 770 "args cannot be on stack anymore"); 771 // initialize InterpretedArgumentOopFinder 772 _f = f; 773 _fr = fr; 774 _offset = args_size; 775 } 776 777 void oops_do() { 778 if (_has_receiver) { 779 --_offset; 780 oop_offset_do(); 781 } 782 iterate_parameters(); 783 } 784}; 785 786 787// Entry frame has following form (n arguments) 788// +-----------+ 789// sp -> | last arg | 790// +-----------+ 791// : ::: : 792// +-----------+ 793// (sp+n)->| first arg| 794// +-----------+ 795 796 797 798// visits and GC's all the arguments in entry frame 799class EntryFrameOopFinder: public SignatureInfo { 800 private: 801 bool _is_static; 802 int _offset; 803 frame* _fr; 804 OopClosure* _f; 805 806 void set(int size, BasicType type) { 807 assert (_offset >= 0, "illegal offset"); 808 if (type == T_OBJECT || type == T_ARRAY) oop_at_offset_do(_offset); 809 _offset -= size; 810 } 811 812 void oop_at_offset_do(int offset) { 813 assert (offset >= 0, "illegal offset"); 814 oop* addr = (oop*) _fr->entry_frame_argument_at(offset); 815 _f->do_oop(addr); 816 } 817 818 public: 819 EntryFrameOopFinder(frame* frame, symbolHandle signature, bool is_static) : SignatureInfo(signature) { 820 _f = NULL; // will be set later 821 _fr = frame; 822 _is_static = is_static; 823 _offset = ArgumentSizeComputer(signature).size() - 1; // last parameter is at index 0 824 } 825 826 void arguments_do(OopClosure* f) { 827 _f = f; 828 if (!_is_static) oop_at_offset_do(_offset+1); // do the receiver 829 iterate_parameters(); 830 } 831 832}; 833 834oop* frame::interpreter_callee_receiver_addr(symbolHandle signature) { 835 ArgumentSizeComputer asc(signature); 836 int size = asc.size(); 837 return (oop *)interpreter_frame_tos_at(size); 838} 839 840 841void frame::oops_interpreted_do(OopClosure* f, const RegisterMap* map, bool query_oop_map_cache) { 842 assert(is_interpreted_frame(), "Not an interpreted frame"); 843 assert(map != NULL, "map must be set"); 844 Thread *thread = Thread::current(); 845 methodHandle m (thread, interpreter_frame_method()); 846 jint bci = interpreter_frame_bci(); 847 848 assert(Universe::heap()->is_in(m()), "must be valid oop"); 849 assert(m->is_method(), "checking frame value"); 850 assert((m->is_native() && bci == 0) || (!m->is_native() && bci >= 0 && bci < m->code_size()), "invalid bci value"); 851 852 // Handle the monitor elements in the activation 853 for ( 854 BasicObjectLock* current = interpreter_frame_monitor_end(); 855 current < interpreter_frame_monitor_begin(); 856 current = next_monitor_in_interpreter_frame(current) 857 ) { 858#ifdef ASSERT 859 interpreter_frame_verify_monitor(current); 860#endif 861 current->oops_do(f); 862 } 863 864 // process fixed part 865 f->do_oop((oop*)interpreter_frame_method_addr()); 866 f->do_oop((oop*)interpreter_frame_cache_addr()); 867 868 // Hmm what about the mdp? 869#ifdef CC_INTERP 870 // Interpreter frame in the midst of a call have a methodOop within the 871 // object. 872 interpreterState istate = get_interpreterState(); 873 if (istate->msg() == BytecodeInterpreter::call_method) { 874 f->do_oop((oop*)&istate->_result._to_call._callee); 875 } 876 877#endif /* CC_INTERP */ 878 879 if (m->is_native()) { 880#ifdef CC_INTERP 881 f->do_oop((oop*)&istate->_oop_temp); 882#else 883 f->do_oop((oop*)( fp() + interpreter_frame_oop_temp_offset )); 884#endif /* CC_INTERP */ 885 } 886 887 int max_locals = m->is_native() ? m->size_of_parameters() : m->max_locals(); 888 889 symbolHandle signature; 890 bool has_receiver = false; 891 892 // Process a callee's arguments if we are at a call site 893 // (i.e., if we are at an invoke bytecode) 894 // This is used sometimes for calling into the VM, not for another 895 // interpreted or compiled frame. 896 if (!m->is_native()) { 897 Bytecode_invoke *call = Bytecode_invoke_at_check(m, bci); 898 if (call != NULL) { 899 signature = symbolHandle(thread, call->signature()); 900 has_receiver = call->has_receiver(); 901 if (map->include_argument_oops() && 902 interpreter_frame_expression_stack_size() > 0) { 903 ResourceMark rm(thread); // is this right ??? 904 // we are at a call site & the expression stack is not empty 905 // => process callee's arguments 906 // 907 // Note: The expression stack can be empty if an exception 908 // occurred during method resolution/execution. In all 909 // cases we empty the expression stack completely be- 910 // fore handling the exception (the exception handling 911 // code in the interpreter calls a blocking runtime 912 // routine which can cause this code to be executed). 913 // (was bug gri 7/27/98) 914 oops_interpreted_arguments_do(signature, has_receiver, f); 915 } 916 } 917 } 918 919 InterpreterFrameClosure blk(this, max_locals, m->max_stack(), f); 920 921 // process locals & expression stack 922 InterpreterOopMap mask; 923 if (query_oop_map_cache) { 924 m->mask_for(bci, &mask); 925 } else { 926 OopMapCache::compute_one_oop_map(m, bci, &mask); 927 } 928 mask.iterate_oop(&blk); 929} 930 931 932void frame::oops_interpreted_arguments_do(symbolHandle signature, bool has_receiver, OopClosure* f) { 933 InterpretedArgumentOopFinder finder(signature, has_receiver, this, f); 934 finder.oops_do(); 935} 936 937void frame::oops_code_blob_do(OopClosure* f, CodeBlobClosure* cf, const RegisterMap* reg_map) { 938 assert(_cb != NULL, "sanity check"); 939 if (_cb->oop_maps() != NULL) { 940 OopMapSet::oops_do(this, reg_map, f); 941 942 // Preserve potential arguments for a callee. We handle this by dispatching 943 // on the codeblob. For c2i, we do 944 if (reg_map->include_argument_oops()) { 945 _cb->preserve_callee_argument_oops(*this, reg_map, f); 946 } 947 } 948 // In cases where perm gen is collected, GC will want to mark 949 // oops referenced from nmethods active on thread stacks so as to 950 // prevent them from being collected. However, this visit should be 951 // restricted to certain phases of the collection only. The 952 // closure decides how it wants nmethods to be traced. 953 if (cf != NULL) 954 cf->do_code_blob(_cb); 955} 956 957class CompiledArgumentOopFinder: public SignatureInfo { 958 protected: 959 OopClosure* _f; 960 int _offset; // the current offset, incremented with each argument 961 bool _has_receiver; // true if the callee has a receiver 962 frame _fr; 963 RegisterMap* _reg_map; 964 int _arg_size; 965 VMRegPair* _regs; // VMReg list of arguments 966 967 void set(int size, BasicType type) { 968 if (type == T_OBJECT || type == T_ARRAY) handle_oop_offset(); 969 _offset += size; 970 } 971 972 virtual void handle_oop_offset() { 973 // Extract low order register number from register array. 974 // In LP64-land, the high-order bits are valid but unhelpful. 975 VMReg reg = _regs[_offset].first(); 976 oop *loc = _fr.oopmapreg_to_location(reg, _reg_map); 977 _f->do_oop(loc); 978 } 979 980 public: 981 CompiledArgumentOopFinder(symbolHandle signature, bool has_receiver, OopClosure* f, frame fr, const RegisterMap* reg_map) 982 : SignatureInfo(signature) { 983 984 // initialize CompiledArgumentOopFinder 985 _f = f; 986 _offset = 0; 987 _has_receiver = has_receiver; 988 _fr = fr; 989 _reg_map = (RegisterMap*)reg_map; 990 _arg_size = ArgumentSizeComputer(signature).size() + (has_receiver ? 1 : 0); 991 992 int arg_size; 993 _regs = SharedRuntime::find_callee_arguments(signature(), has_receiver, &arg_size); 994 assert(arg_size == _arg_size, "wrong arg size"); 995 } 996 997 void oops_do() { 998 if (_has_receiver) { 999 handle_oop_offset(); 1000 _offset++; 1001 } 1002 iterate_parameters(); 1003 } 1004}; 1005 1006void frame::oops_compiled_arguments_do(symbolHandle signature, bool has_receiver, const RegisterMap* reg_map, OopClosure* f) { 1007 ResourceMark rm; 1008 CompiledArgumentOopFinder finder(signature, has_receiver, f, *this, reg_map); 1009 finder.oops_do(); 1010} 1011 1012 1013// Get receiver out of callers frame, i.e. find parameter 0 in callers 1014// frame. Consult ADLC for where parameter 0 is to be found. Then 1015// check local reg_map for it being a callee-save register or argument 1016// register, both of which are saved in the local frame. If not found 1017// there, it must be an in-stack argument of the caller. 1018// Note: caller.sp() points to callee-arguments 1019oop frame::retrieve_receiver(RegisterMap* reg_map) { 1020 frame caller = *this; 1021 1022 // First consult the ADLC on where it puts parameter 0 for this signature. 1023 VMReg reg = SharedRuntime::name_for_receiver(); 1024 oop r = *caller.oopmapreg_to_location(reg, reg_map); 1025 assert( Universe::heap()->is_in_or_null(r), "bad receiver" ); 1026 return r; 1027} 1028 1029 1030oop* frame::oopmapreg_to_location(VMReg reg, const RegisterMap* reg_map) const { 1031 if(reg->is_reg()) { 1032 // If it is passed in a register, it got spilled in the stub frame. 1033 return (oop *)reg_map->location(reg); 1034 } else { 1035 int sp_offset_in_bytes = reg->reg2stack() * VMRegImpl::stack_slot_size; 1036 return (oop*)(((address)unextended_sp()) + sp_offset_in_bytes); 1037 } 1038} 1039 1040BasicLock* frame::compiled_synchronized_native_monitor(nmethod* nm) { 1041 if (nm == NULL) { 1042 assert(_cb != NULL && _cb->is_nmethod() && 1043 nm->method()->is_native() && 1044 nm->method()->is_synchronized(), 1045 "should not call this otherwise"); 1046 nm = (nmethod*) _cb; 1047 } 1048 int byte_offset = in_bytes(nm->compiled_synchronized_native_basic_lock_sp_offset()); 1049 assert(byte_offset >= 0, "should not see invalid offset"); 1050 return (BasicLock*) &sp()[byte_offset / wordSize]; 1051} 1052 1053oop frame::compiled_synchronized_native_monitor_owner(nmethod* nm) { 1054 if (nm == NULL) { 1055 assert(_cb != NULL && _cb->is_nmethod() && 1056 nm->method()->is_native() && 1057 nm->method()->is_synchronized(), 1058 "should not call this otherwise"); 1059 nm = (nmethod*) _cb; 1060 } 1061 int byte_offset = in_bytes(nm->compiled_synchronized_native_basic_lock_owner_sp_offset()); 1062 assert(byte_offset >= 0, "should not see invalid offset"); 1063 oop owner = ((oop*) sp())[byte_offset / wordSize]; 1064 assert( Universe::heap()->is_in(owner), "bad receiver" ); 1065 return owner; 1066} 1067 1068void frame::oops_entry_do(OopClosure* f, const RegisterMap* map) { 1069 assert(map != NULL, "map must be set"); 1070 if (map->include_argument_oops()) { 1071 // must collect argument oops, as nobody else is doing it 1072 Thread *thread = Thread::current(); 1073 methodHandle m (thread, entry_frame_call_wrapper()->callee_method()); 1074 symbolHandle signature (thread, m->signature()); 1075 EntryFrameOopFinder finder(this, signature, m->is_static()); 1076 finder.arguments_do(f); 1077 } 1078 // Traverse the Handle Block saved in the entry frame 1079 entry_frame_call_wrapper()->oops_do(f); 1080} 1081 1082 1083void frame::oops_do_internal(OopClosure* f, CodeBlobClosure* cf, RegisterMap* map, bool use_interpreter_oop_map_cache) { 1084#ifndef PRODUCT 1085 // simulate GC crash here to dump java thread in error report 1086 if (CrashGCForDumpingJavaThread) { 1087 char *t = NULL; 1088 *t = 'c'; 1089 } 1090#endif 1091 if (is_interpreted_frame()) { 1092 oops_interpreted_do(f, map, use_interpreter_oop_map_cache); 1093 } else if (is_entry_frame()) { 1094 oops_entry_do(f, map); 1095 } else if (CodeCache::contains(pc())) { 1096 oops_code_blob_do(f, cf, map); 1097 } else { 1098 ShouldNotReachHere(); 1099 } 1100} 1101 1102void frame::nmethods_do(CodeBlobClosure* cf) { 1103 if (_cb != NULL && _cb->is_nmethod()) { 1104 cf->do_code_blob(_cb); 1105 } 1106} 1107 1108 1109void frame::gc_prologue() { 1110 if (is_interpreted_frame()) { 1111 // set bcx to bci to become methodOop position independent during GC 1112 interpreter_frame_set_bcx(interpreter_frame_bci()); 1113 } 1114} 1115 1116 1117void frame::gc_epilogue() { 1118 if (is_interpreted_frame()) { 1119 // set bcx back to bcp for interpreter 1120 interpreter_frame_set_bcx((intptr_t)interpreter_frame_bcp()); 1121 } 1122 // call processor specific epilog function 1123 pd_gc_epilog(); 1124} 1125 1126 1127# ifdef ENABLE_ZAP_DEAD_LOCALS 1128 1129void frame::CheckValueClosure::do_oop(oop* p) { 1130 if (CheckOopishValues && Universe::heap()->is_in_reserved(*p)) { 1131 warning("value @ " INTPTR_FORMAT " looks oopish (" INTPTR_FORMAT ") (thread = " INTPTR_FORMAT ")", p, (address)*p, Thread::current()); 1132 } 1133} 1134frame::CheckValueClosure frame::_check_value; 1135 1136 1137void frame::CheckOopClosure::do_oop(oop* p) { 1138 if (*p != NULL && !(*p)->is_oop()) { 1139 warning("value @ " INTPTR_FORMAT " should be an oop (" INTPTR_FORMAT ") (thread = " INTPTR_FORMAT ")", p, (address)*p, Thread::current()); 1140 } 1141} 1142frame::CheckOopClosure frame::_check_oop; 1143 1144void frame::check_derived_oop(oop* base, oop* derived) { 1145 _check_oop.do_oop(base); 1146} 1147 1148 1149void frame::ZapDeadClosure::do_oop(oop* p) { 1150 if (TraceZapDeadLocals) tty->print_cr("zapping @ " INTPTR_FORMAT " containing " INTPTR_FORMAT, p, (address)*p); 1151 // Need cast because on _LP64 the conversion to oop is ambiguous. Constant 1152 // can be either long or int. 1153 *p = (oop)(int)0xbabebabe; 1154} 1155frame::ZapDeadClosure frame::_zap_dead; 1156 1157void frame::zap_dead_locals(JavaThread* thread, const RegisterMap* map) { 1158 assert(thread == Thread::current(), "need to synchronize to do this to another thread"); 1159 // Tracing - part 1 1160 if (TraceZapDeadLocals) { 1161 ResourceMark rm(thread); 1162 tty->print_cr("--------------------------------------------------------------------------------"); 1163 tty->print("Zapping dead locals in "); 1164 print_on(tty); 1165 tty->cr(); 1166 } 1167 // Zapping 1168 if (is_entry_frame ()) zap_dead_entry_locals (thread, map); 1169 else if (is_interpreted_frame()) zap_dead_interpreted_locals(thread, map); 1170 else if (is_compiled_frame()) zap_dead_compiled_locals (thread, map); 1171 1172 else 1173 // could be is_runtime_frame 1174 // so remove error: ShouldNotReachHere(); 1175 ; 1176 // Tracing - part 2 1177 if (TraceZapDeadLocals) { 1178 tty->cr(); 1179 } 1180} 1181 1182 1183void frame::zap_dead_interpreted_locals(JavaThread *thread, const RegisterMap* map) { 1184 // get current interpreter 'pc' 1185 assert(is_interpreted_frame(), "Not an interpreted frame"); 1186 methodOop m = interpreter_frame_method(); 1187 int bci = interpreter_frame_bci(); 1188 1189 int max_locals = m->is_native() ? m->size_of_parameters() : m->max_locals(); 1190 1191 // process dynamic part 1192 InterpreterFrameClosure value_blk(this, max_locals, m->max_stack(), 1193 &_check_value); 1194 InterpreterFrameClosure oop_blk(this, max_locals, m->max_stack(), 1195 &_check_oop ); 1196 InterpreterFrameClosure dead_blk(this, max_locals, m->max_stack(), 1197 &_zap_dead ); 1198 1199 // get frame map 1200 InterpreterOopMap mask; 1201 m->mask_for(bci, &mask); 1202 mask.iterate_all( &oop_blk, &value_blk, &dead_blk); 1203} 1204 1205 1206void frame::zap_dead_compiled_locals(JavaThread* thread, const RegisterMap* reg_map) { 1207 1208 ResourceMark rm(thread); 1209 assert(_cb != NULL, "sanity check"); 1210 if (_cb->oop_maps() != NULL) { 1211 OopMapSet::all_do(this, reg_map, &_check_oop, check_derived_oop, &_check_value); 1212 } 1213} 1214 1215 1216void frame::zap_dead_entry_locals(JavaThread*, const RegisterMap*) { 1217 if (TraceZapDeadLocals) warning("frame::zap_dead_entry_locals unimplemented"); 1218} 1219 1220 1221void frame::zap_dead_deoptimized_locals(JavaThread*, const RegisterMap*) { 1222 if (TraceZapDeadLocals) warning("frame::zap_dead_deoptimized_locals unimplemented"); 1223} 1224 1225# endif // ENABLE_ZAP_DEAD_LOCALS 1226 1227void frame::verify(const RegisterMap* map) { 1228 // for now make sure receiver type is correct 1229 if (is_interpreted_frame()) { 1230 methodOop method = interpreter_frame_method(); 1231 guarantee(method->is_method(), "method is wrong in frame::verify"); 1232 if (!method->is_static()) { 1233 // fetch the receiver 1234 oop* p = (oop*) interpreter_frame_local_at(0); 1235 // make sure we have the right receiver type 1236 } 1237 } 1238 COMPILER2_PRESENT(assert(DerivedPointerTable::is_empty(), "must be empty before verify");) 1239 oops_do_internal(&VerifyOopClosure::verify_oop, NULL, (RegisterMap*)map, false); 1240} 1241 1242 1243#ifdef ASSERT 1244bool frame::verify_return_pc(address x) { 1245 if (StubRoutines::returns_to_call_stub(x)) { 1246 return true; 1247 } 1248 if (CodeCache::contains(x)) { 1249 return true; 1250 } 1251 if (Interpreter::contains(x)) { 1252 return true; 1253 } 1254 return false; 1255} 1256#endif 1257 1258 1259#ifdef ASSERT 1260void frame::interpreter_frame_verify_monitor(BasicObjectLock* value) const { 1261 assert(is_interpreted_frame(), "Not an interpreted frame"); 1262 // verify that the value is in the right part of the frame 1263 address low_mark = (address) interpreter_frame_monitor_end(); 1264 address high_mark = (address) interpreter_frame_monitor_begin(); 1265 address current = (address) value; 1266 1267 const int monitor_size = frame::interpreter_frame_monitor_size(); 1268 guarantee((high_mark - current) % monitor_size == 0 , "Misaligned top of BasicObjectLock*"); 1269 guarantee( high_mark > current , "Current BasicObjectLock* higher than high_mark"); 1270 1271 guarantee((current - low_mark) % monitor_size == 0 , "Misaligned bottom of BasicObjectLock*"); 1272 guarantee( current >= low_mark , "Current BasicObjectLock* below than low_mark"); 1273} 1274#endif 1275 1276 1277//----------------------------------------------------------------------------------- 1278// StackFrameStream implementation 1279 1280StackFrameStream::StackFrameStream(JavaThread *thread, bool update) : _reg_map(thread, update) { 1281 assert(thread->has_last_Java_frame(), "sanity check"); 1282 _fr = thread->last_frame(); 1283 _is_done = false; 1284} 1285