1 /*
   2  * Copyright (c) 1997, 2025, 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 "classfile/moduleEntry.hpp"
  26 #include "code/codeCache.hpp"
  27 #include "code/scopeDesc.hpp"
  28 #include "code/vmreg.inline.hpp"
  29 #include "compiler/abstractCompiler.hpp"
  30 #include "compiler/disassembler.hpp"
  31 #include "compiler/oopMap.hpp"
  32 #include "gc/shared/collectedHeap.inline.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "interpreter/oopMapCache.hpp"
  35 #include "logging/log.hpp"
  36 #include "memory/resourceArea.hpp"
  37 #include "memory/universe.hpp"
  38 #include "oops/markWord.hpp"
  39 #include "oops/method.inline.hpp"
  40 #include "oops/methodData.hpp"
  41 #include "oops/oop.inline.hpp"
  42 #include "oops/stackChunkOop.inline.hpp"
  43 #include "oops/verifyOopClosure.hpp"
  44 #include "prims/methodHandles.hpp"
  45 #include "runtime/continuation.hpp"
  46 #include "runtime/continuationEntry.inline.hpp"
  47 #include "runtime/frame.inline.hpp"
  48 #include "runtime/handles.inline.hpp"
  49 #include "runtime/javaCalls.hpp"
  50 #include "runtime/javaThread.hpp"
  51 #include "runtime/monitorChunk.hpp"
  52 #include "runtime/os.hpp"
  53 #include "runtime/safefetch.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/signature.hpp"
  56 #include "runtime/stackValue.hpp"
  57 #include "runtime/stubCodeGenerator.hpp"
  58 #include "runtime/stubRoutines.hpp"
  59 #include "utilities/debug.hpp"
  60 #include "utilities/decoder.hpp"
  61 #include "utilities/formatBuffer.hpp"
  62 
  63 RegisterMap::RegisterMap(JavaThread *thread, UpdateMap update_map, ProcessFrames process_frames, WalkContinuation walk_cont) {
  64   _thread         = thread;
  65   _update_map     = update_map == UpdateMap::include;
  66   _process_frames = process_frames == ProcessFrames::include;
  67   _walk_cont      = walk_cont == WalkContinuation::include;
  68   clear();
  69   DEBUG_ONLY (_update_for_id = nullptr;)
  70   NOT_PRODUCT(_skip_missing = false;)
  71   NOT_PRODUCT(_async = false;)
  72 
  73   if (walk_cont == WalkContinuation::include && thread != nullptr && thread->last_continuation() != nullptr) {
  74     _chunk = stackChunkHandle(Thread::current()->handle_area()->allocate_null_handle(), true /* dummy */);
  75   }
  76   _chunk_index = -1;
  77 
  78 #ifndef PRODUCT
  79   for (int i = 0; i < reg_count ; i++ ) _location[i] = nullptr;
  80 #endif /* PRODUCT */
  81 }
  82 
  83 RegisterMap::RegisterMap(oop continuation, UpdateMap update_map) {
  84   _thread         = nullptr;
  85   _update_map     = update_map == UpdateMap::include;
  86   _process_frames = false;
  87   _walk_cont      = true;
  88   clear();
  89   DEBUG_ONLY (_update_for_id = nullptr;)
  90   NOT_PRODUCT(_skip_missing = false;)
  91   NOT_PRODUCT(_async = false;)
  92 
  93   _chunk = stackChunkHandle(Thread::current()->handle_area()->allocate_null_handle(), true /* dummy */);
  94   _chunk_index = -1;
  95 
  96 #ifndef PRODUCT
  97   for (int i = 0; i < reg_count ; i++ ) _location[i] = nullptr;
  98 #endif /* PRODUCT */
  99 }
 100 
 101 RegisterMap::RegisterMap(const RegisterMap* map) {
 102   assert(map != this, "bad initialization parameter");
 103   assert(map != nullptr, "RegisterMap must be present");
 104   _thread                = map->thread();
 105   _update_map            = map->update_map();
 106   _process_frames        = map->process_frames();
 107   _walk_cont             = map->_walk_cont;
 108   _include_argument_oops = map->include_argument_oops();
 109   DEBUG_ONLY (_update_for_id = map->_update_for_id;)
 110   NOT_PRODUCT(_skip_missing = map->_skip_missing;)
 111   NOT_PRODUCT(_async = map->_async;)
 112 
 113   // only the original RegisterMap's handle lives long enough for StackWalker; this is bound to cause trouble with nested continuations.
 114   _chunk = map->_chunk;
 115   _chunk_index = map->_chunk_index;
 116 
 117   pd_initialize_from(map);
 118   if (update_map()) {
 119     for(int i = 0; i < location_valid_size; i++) {
 120       LocationValidType bits = map->_location_valid[i];
 121       _location_valid[i] = bits;
 122       // for whichever bits are set, pull in the corresponding map->_location
 123       int j = i*location_valid_type_size;
 124       while (bits != 0) {
 125         if ((bits & 1) != 0) {
 126           assert(0 <= j && j < reg_count, "range check");
 127           _location[j] = map->_location[j];
 128         }
 129         bits >>= 1;
 130         j += 1;
 131       }
 132     }
 133   }
 134 }
 135 
 136 oop RegisterMap::cont() const {
 137   return _chunk() != nullptr ? _chunk()->cont() : (oop)nullptr;
 138 }
 139 
 140 void RegisterMap::set_stack_chunk(stackChunkOop chunk) {
 141   assert(chunk == nullptr || _walk_cont, "");
 142   assert(chunk == nullptr || _chunk.not_null(), "");
 143   if (_chunk.is_null()) return;
 144   log_trace(continuations)("set_stack_chunk: " INTPTR_FORMAT " this: " INTPTR_FORMAT, p2i((oopDesc*)chunk), p2i(this));
 145   _chunk.replace(chunk); // reuse handle. see comment above in the constructor
 146   if (chunk == nullptr) {
 147     _chunk_index = -1;
 148   } else {
 149     _chunk_index++;
 150   }
 151 }
 152 
 153 void RegisterMap::clear() {
 154   set_include_argument_oops(true);
 155   if (update_map()) {
 156     for(int i = 0; i < location_valid_size; i++) {
 157       _location_valid[i] = 0;
 158     }
 159     pd_clear();
 160   } else {
 161     pd_initialize();
 162   }
 163 }
 164 
 165 #ifndef PRODUCT
 166 
 167 VMReg RegisterMap::find_register_spilled_here(void* p, intptr_t* sp) {
 168   for(int i = 0; i < RegisterMap::reg_count; i++) {
 169     VMReg r = VMRegImpl::as_VMReg(i);
 170     if (p == location(r, sp)) return r;
 171   }
 172   return nullptr;
 173 }
 174 
 175 void RegisterMap::print_on(outputStream* st) const {
 176   st->print_cr("Register map");
 177   for(int i = 0; i < reg_count; i++) {
 178 
 179     VMReg r = VMRegImpl::as_VMReg(i);
 180     intptr_t* src = (intptr_t*) location(r, nullptr);
 181     if (src != nullptr) {
 182 
 183       r->print_on(st);
 184       st->print(" [" INTPTR_FORMAT "] = ", p2i(src));
 185       if (((uintptr_t)src & (sizeof(*src)-1)) != 0) {
 186         st->print_cr("<misaligned>");
 187       } else {
 188         st->print_cr(INTPTR_FORMAT, *src);
 189       }
 190     }
 191   }
 192 }
 193 
 194 void RegisterMap::print() const {
 195   print_on(tty);
 196 }
 197 
 198 #endif
 199 // This returns the pc that if you were in the debugger you'd see. Not
 200 // the idealized value in the frame object. This undoes the magic conversion
 201 // that happens for deoptimized frames. In addition it makes the value the
 202 // hardware would want to see in the native frame. The only user (at this point)
 203 // is deoptimization. It likely no one else should ever use it.
 204 
 205 address frame::raw_pc() const {
 206   if (is_deoptimized_frame()) {
 207     nmethod* nm = cb()->as_nmethod_or_null();
 208     assert(nm != nullptr, "only nmethod is expected here");
 209     return nm->deopt_handler_begin() - pc_return_offset;
 210   } else {
 211     return (pc() - pc_return_offset);
 212   }
 213 }
 214 
 215 // Change the pc in a frame object. This does not change the actual pc in
 216 // actual frame. To do that use patch_pc.
 217 //
 218 void frame::set_pc(address newpc) {
 219 #ifdef ASSERT
 220   if (_cb != nullptr && _cb->is_nmethod()) {
 221     assert(!((nmethod*)_cb)->is_deopt_pc(_pc), "invariant violation");
 222   }
 223 #endif // ASSERT
 224 
 225   // Unsafe to use the is_deoptimized tester after changing pc
 226   _deopt_state = unknown;
 227   _pc = newpc;
 228   _cb = CodeCache::find_blob(_pc);
 229 }
 230 
 231 // This is optimized for intra-blob pc adjustments only.
 232 void frame::adjust_pc(address newpc) {
 233   assert(_cb != nullptr, "invariant");
 234   assert(_cb == CodeCache::find_blob(newpc), "invariant");
 235   // Unsafe to use the is_deoptimized tester after changing pc
 236   _deopt_state = unknown;
 237   _pc = newpc;
 238 }
 239 
 240 // type testers
 241 bool frame::is_ignored_frame() const {
 242   return false;  // FIXME: some LambdaForm frames should be ignored
 243 }
 244 
 245 bool frame::is_native_frame() const {
 246   return (_cb != nullptr &&
 247           _cb->is_nmethod() &&
 248           ((nmethod*)_cb)->is_native_method());
 249 }
 250 
 251 bool frame::is_java_frame() const {
 252   if (is_interpreted_frame()) return true;
 253   if (is_compiled_frame())    return true;
 254   return false;
 255 }
 256 
 257 bool frame::is_runtime_frame() const {
 258   return (_cb != nullptr && _cb->is_runtime_stub());
 259 }
 260 
 261 bool frame::is_safepoint_blob_frame() const {
 262   return (_cb != nullptr && _cb->is_safepoint_stub());
 263 }
 264 
 265 // testers
 266 
 267 bool frame::is_first_java_frame() const {
 268   RegisterMap map(JavaThread::current(),
 269                   RegisterMap::UpdateMap::skip,
 270                   RegisterMap::ProcessFrames::include,
 271                   RegisterMap::WalkContinuation::skip); // No update
 272   frame s;
 273   for (s = sender(&map); !(s.is_java_frame() || s.is_first_frame()); s = s.sender(&map));
 274   return s.is_first_frame();
 275 }
 276 
 277 bool frame::is_first_vthread_frame(JavaThread* thread) const {
 278   return Continuation::is_continuation_enterSpecial(*this)
 279     && Continuation::get_continuation_entry_for_entry_frame(thread, *this)->is_virtual_thread();
 280 }
 281 
 282 bool frame::entry_frame_is_first() const {
 283   return entry_frame_call_wrapper()->is_first_frame();
 284 }
 285 
 286 JavaCallWrapper* frame::entry_frame_call_wrapper_if_safe(JavaThread* thread) const {
 287   JavaCallWrapper** jcw = entry_frame_call_wrapper_addr();
 288   address addr = (address) jcw;
 289 
 290   // addr must be within the usable part of the stack
 291   if (thread->is_in_usable_stack(addr)) {
 292     return *jcw;
 293   }
 294 
 295   return nullptr;
 296 }
 297 
 298 bool frame::is_entry_frame_valid(JavaThread* thread) const {
 299   // Validate the JavaCallWrapper an entry frame must have
 300   address jcw = (address)entry_frame_call_wrapper();
 301   if (!thread->is_in_stack_range_excl(jcw, (address)fp())) {
 302     return false;
 303   }
 304 
 305   // Validate sp saved in the java frame anchor
 306   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 307   return (jfa->last_Java_sp() > sp());
 308 }
 309 
 310 Method* frame::safe_interpreter_frame_method() const {
 311   Method** m_addr = interpreter_frame_method_addr();
 312   if (m_addr == nullptr) {
 313     return nullptr;
 314   }
 315   return (Method*) SafeFetchN((intptr_t*) m_addr, 0);
 316 }
 317 
 318 bool frame::should_be_deoptimized() const {
 319   if (_deopt_state == is_deoptimized ||
 320       !is_compiled_frame() ) return false;
 321   assert(_cb != nullptr && _cb->is_nmethod(), "must be an nmethod");
 322   nmethod* nm = _cb->as_nmethod();
 323   LogTarget(Debug, dependencies) lt;
 324   if (lt.is_enabled()) {
 325     LogStream ls(&lt);
 326     ls.print("checking (%s) ", nm->is_marked_for_deoptimization() ? "true" : "false");
 327     nm->print_value_on(&ls);
 328     ls.cr();
 329   }
 330 
 331   if( !nm->is_marked_for_deoptimization() )
 332     return false;
 333 
 334   // If at the return point, then the frame has already been popped, and
 335   // only the return needs to be executed. Don't deoptimize here.
 336   return !nm->is_at_poll_return(pc());
 337 }
 338 
 339 bool frame::can_be_deoptimized() const {
 340   if (!is_compiled_frame()) return false;
 341   nmethod* nm = _cb->as_nmethod();
 342 
 343   if(!nm->can_be_deoptimized())
 344     return false;
 345 
 346   return !nm->is_at_poll_return(pc());
 347 }
 348 
 349 void frame::deoptimize(JavaThread* thread) {
 350   assert(thread == nullptr
 351          || (thread->frame_anchor()->has_last_Java_frame() &&
 352              thread->frame_anchor()->walkable()), "must be");
 353   // Schedule deoptimization of an nmethod activation with this frame.
 354   assert(_cb != nullptr && _cb->is_nmethod(), "must be");
 355 
 356   // If the call site is a MethodHandle call site use the MH deopt handler.
 357   nmethod* nm = _cb->as_nmethod();
 358   address deopt = nm->deopt_handler_begin();
 359 
 360   NativePostCallNop* inst = nativePostCallNop_at(pc());
 361 
 362   // Save the original pc before we patch in the new one
 363   nm->set_original_pc(this, pc());
 364   patch_pc(thread, deopt);
 365   assert(is_deoptimized_frame(), "must be");
 366 
 367 #ifdef ASSERT
 368   if (thread != nullptr) {
 369     frame check = thread->last_frame();
 370     if (is_older(check.id())) {
 371       RegisterMap map(thread,
 372                       RegisterMap::UpdateMap::skip,
 373                       RegisterMap::ProcessFrames::include,
 374                       RegisterMap::WalkContinuation::skip);
 375       while (id() != check.id()) {
 376         check = check.sender(&map);
 377       }
 378       assert(check.is_deoptimized_frame(), "missed deopt");
 379     }
 380   }
 381 #endif // ASSERT
 382 }
 383 
 384 frame frame::java_sender() const {
 385   RegisterMap map(JavaThread::current(),
 386                   RegisterMap::UpdateMap::skip,
 387                   RegisterMap::ProcessFrames::include,
 388                   RegisterMap::WalkContinuation::skip);
 389   frame s;
 390   for (s = sender(&map); !(s.is_java_frame() || s.is_first_frame()); s = s.sender(&map)) ;
 391   guarantee(s.is_java_frame(), "tried to get caller of first java frame");
 392   return s;
 393 }
 394 
 395 frame frame::real_sender(RegisterMap* map) const {
 396   frame result = sender(map);
 397   while (result.is_runtime_frame() ||
 398          result.is_ignored_frame()) {
 399     result = result.sender(map);
 400   }
 401   return result;
 402 }
 403 
 404 // Interpreter frames
 405 
 406 
 407 Method* frame::interpreter_frame_method() const {
 408   assert(is_interpreted_frame(), "interpreted frame expected");
 409   Method* m = *interpreter_frame_method_addr();
 410   assert(m->is_method(), "not a Method*");
 411   return m;
 412 }
 413 
 414 void frame::interpreter_frame_set_method(Method* method) {
 415   assert(is_interpreted_frame(), "interpreted frame expected");
 416   *interpreter_frame_method_addr() = method;
 417 }
 418 
 419 void frame::interpreter_frame_set_mirror(oop mirror) {
 420   assert(is_interpreted_frame(), "interpreted frame expected");
 421   *interpreter_frame_mirror_addr() = mirror;
 422 }
 423 
 424 jint frame::interpreter_frame_bci() const {
 425   assert(is_interpreted_frame(), "interpreted frame expected");
 426   address bcp = interpreter_frame_bcp();
 427   return interpreter_frame_method()->bci_from(bcp);
 428 }
 429 
 430 address frame::interpreter_frame_bcp() const {
 431   assert(is_interpreted_frame(), "interpreted frame expected");
 432   address bcp = (address)*interpreter_frame_bcp_addr();
 433   return interpreter_frame_method()->bcp_from(bcp);
 434 }
 435 
 436 void frame::interpreter_frame_set_bcp(address bcp) {
 437   assert(is_interpreted_frame(), "interpreted frame expected");
 438   *interpreter_frame_bcp_addr() = (intptr_t)bcp;
 439 }
 440 
 441 address frame::interpreter_frame_mdp() const {
 442   assert(ProfileInterpreter, "must be profiling interpreter");
 443   assert(is_interpreted_frame(), "interpreted frame expected");
 444   return (address)*interpreter_frame_mdp_addr();
 445 }
 446 
 447 void frame::interpreter_frame_set_mdp(address mdp) {
 448   assert(is_interpreted_frame(), "interpreted frame expected");
 449   assert(ProfileInterpreter, "must be profiling interpreter");
 450   *interpreter_frame_mdp_addr() = (intptr_t)mdp;
 451 }
 452 
 453 BasicObjectLock* frame::next_monitor_in_interpreter_frame(BasicObjectLock* current) const {
 454   assert(is_interpreted_frame(), "Not an interpreted frame");
 455 #ifdef ASSERT
 456   interpreter_frame_verify_monitor(current);
 457 #endif
 458   BasicObjectLock* next = (BasicObjectLock*) (((intptr_t*) current) + interpreter_frame_monitor_size());
 459   return next;
 460 }
 461 
 462 BasicObjectLock* frame::previous_monitor_in_interpreter_frame(BasicObjectLock* current) const {
 463   assert(is_interpreted_frame(), "Not an interpreted frame");
 464 #ifdef ASSERT
 465 //   // This verification needs to be checked before being enabled
 466 //   interpreter_frame_verify_monitor(current);
 467 #endif
 468   BasicObjectLock* previous = (BasicObjectLock*) (((intptr_t*) current) - interpreter_frame_monitor_size());
 469   return previous;
 470 }
 471 
 472 // Interpreter locals and expression stack locations.
 473 
 474 intptr_t* frame::interpreter_frame_local_at(int index) const {
 475   const int n = Interpreter::local_offset_in_bytes(index)/wordSize;
 476   intptr_t* first = interpreter_frame_locals();
 477   return &(first[n]);
 478 }
 479 
 480 intptr_t* frame::interpreter_frame_expression_stack_at(jint offset) const {
 481   const int i = offset * interpreter_frame_expression_stack_direction();
 482   const int n = i * Interpreter::stackElementWords;
 483   return &(interpreter_frame_expression_stack()[n]);
 484 }
 485 
 486 jint frame::interpreter_frame_expression_stack_size() const {
 487   // Number of elements on the interpreter expression stack
 488   // Callers should span by stackElementWords
 489   int element_size = Interpreter::stackElementWords;
 490   size_t stack_size = 0;
 491   if (frame::interpreter_frame_expression_stack_direction() < 0) {
 492     stack_size = (interpreter_frame_expression_stack() -
 493                   interpreter_frame_tos_address() + 1)/element_size;
 494   } else {
 495     stack_size = (interpreter_frame_tos_address() -
 496                   interpreter_frame_expression_stack() + 1)/element_size;
 497   }
 498   assert(stack_size <= (size_t)max_jint, "stack size too big");
 499   return (jint)stack_size;
 500 }
 501 
 502 // (frame::interpreter_frame_sender_sp accessor is in frame_<arch>.cpp)
 503 
 504 const char* frame::print_name() const {
 505   if (is_native_frame())      return "Native";
 506   if (is_interpreted_frame()) return "Interpreted";
 507   if (is_compiled_frame()) {
 508     if (is_deoptimized_frame()) return "Deoptimized";
 509     return "Compiled";
 510   }
 511   if (sp() == nullptr)            return "Empty";
 512   return "C";
 513 }
 514 
 515 void frame::print_value_on(outputStream* st) const {
 516   NOT_PRODUCT(address begin = pc()-40;)
 517   NOT_PRODUCT(address end   = nullptr;)
 518 
 519   st->print("%s frame (sp=" INTPTR_FORMAT " unextended sp=" INTPTR_FORMAT, print_name(), p2i(sp()), p2i(unextended_sp()));
 520   if (sp() != nullptr)
 521     st->print(", fp=" INTPTR_FORMAT ", real_fp=" INTPTR_FORMAT ", pc=" INTPTR_FORMAT,
 522               p2i(fp()), p2i(real_fp()), p2i(pc()));
 523   st->print_cr(")");
 524 
 525   if (StubRoutines::contains(pc())) {
 526     StubCodeDesc* desc = StubCodeDesc::desc_for(pc());
 527     st->print("~Stub::%s", desc->name());
 528     NOT_PRODUCT(begin = desc->begin(); end = desc->end();)
 529   } else if (Interpreter::contains(pc())) {
 530     InterpreterCodelet* desc = Interpreter::codelet_containing(pc());
 531     if (desc != nullptr) {
 532       st->print("~");
 533       desc->print_on(st);
 534       NOT_PRODUCT(begin = desc->code_begin(); end = desc->code_end();)
 535     } else {
 536       st->print("~interpreter");
 537     }
 538   }
 539 
 540 #ifndef PRODUCT
 541   if (_cb != nullptr) {
 542     st->print("     ");
 543     _cb->print_value_on(st);
 544     if (end == nullptr) {
 545       begin = _cb->code_begin();
 546       end   = _cb->code_end();
 547     }
 548   }
 549   if (WizardMode && Verbose) Disassembler::decode(begin, end);
 550 #endif
 551 }
 552 
 553 void frame::print_on(outputStream* st) const {
 554   print_value_on(st);
 555   if (is_interpreted_frame()) {
 556     interpreter_frame_print_on(st);
 557   }
 558 }
 559 
 560 void frame::interpreter_frame_print_on(outputStream* st) const {
 561 #ifndef PRODUCT
 562   assert(is_interpreted_frame(), "Not an interpreted frame");
 563   jint i;
 564   for (i = 0; i < interpreter_frame_method()->max_locals(); i++ ) {
 565     intptr_t x = *interpreter_frame_local_at(i);
 566     st->print(" - local  [" INTPTR_FORMAT "]", x);
 567     st->fill_to(23);
 568     st->print_cr("; #%d", i);
 569   }
 570   for (i = interpreter_frame_expression_stack_size() - 1; i >= 0; --i ) {
 571     intptr_t x = *interpreter_frame_expression_stack_at(i);
 572     st->print(" - stack  [" INTPTR_FORMAT "]", x);
 573     st->fill_to(23);
 574     st->print_cr("; #%d", i);
 575   }
 576   // locks for synchronization
 577   for (BasicObjectLock* current = interpreter_frame_monitor_end();
 578        current < interpreter_frame_monitor_begin();
 579        current = next_monitor_in_interpreter_frame(current)) {
 580     st->print(" - obj    [%s", current->obj() == nullptr ? "null" : "");
 581     oop obj = current->obj();
 582     if (obj != nullptr) {
 583       if (!is_heap_frame()) {
 584         obj->print_value_on(st);
 585       } else {
 586         // Might be an invalid oop. We don't have the
 587         // stackChunk to correct it so just print address.
 588         st->print(INTPTR_FORMAT, p2i(obj));
 589       }
 590     }
 591     st->print_cr("]");
 592     st->print(" - lock   [");
 593     if (!is_heap_frame()) {
 594       current->lock()->print_on(st, obj);
 595     }
 596     st->print_cr("]");
 597   }
 598   // monitor
 599   st->print_cr(" - monitor[" INTPTR_FORMAT "]", p2i(interpreter_frame_monitor_begin()));
 600   // bcp
 601   st->print(" - bcp    [" INTPTR_FORMAT "]", p2i(interpreter_frame_bcp()));
 602   st->fill_to(23);
 603   st->print_cr("; @%d", interpreter_frame_bci());
 604   // locals
 605   st->print_cr(" - locals [" INTPTR_FORMAT "]", p2i(interpreter_frame_local_at(0)));
 606   // method
 607   st->print(" - method [" INTPTR_FORMAT "]", p2i(interpreter_frame_method()));
 608   st->fill_to(23);
 609   st->print("; ");
 610   interpreter_frame_method()->print_name(st);
 611   st->cr();
 612 #endif
 613 }
 614 
 615 // Print whether the frame is in the VM or OS indicating a HotSpot problem.
 616 // Otherwise, it's likely a bug in the native library that the Java code calls,
 617 // hopefully indicating where to submit bugs.
 618 void frame::print_C_frame(outputStream* st, char* buf, int buflen, address pc) {
 619   // C/C++ frame
 620   bool in_vm = os::address_is_in_vm(pc);
 621   st->print(in_vm ? "V" : "C");
 622 
 623   int offset;
 624   bool found;
 625 
 626   if (buf == nullptr || buflen < 1) return;
 627   // libname
 628   buf[0] = '\0';
 629   found = os::dll_address_to_library_name(pc, buf, buflen, &offset);
 630   if (found && buf[0] != '\0') {
 631     // skip directory names
 632     const char *p1, *p2;
 633     p1 = buf;
 634     int len = (int)strlen(os::file_separator());
 635     while ((p2 = strstr(p1, os::file_separator())) != nullptr) p1 = p2 + len;
 636     st->print("  [%s+0x%x]", p1, offset);
 637   } else {
 638     st->print("  " PTR_FORMAT, p2i(pc));
 639   }
 640 
 641   found = os::dll_address_to_function_name(pc, buf, buflen, &offset);
 642   if (found) {
 643     st->print("  %s+0x%x", buf, offset);
 644   }
 645 }
 646 
 647 // frame::print_on_error() is called by fatal error handler. Notice that we may
 648 // crash inside this function if stack frame is corrupted. The fatal error
 649 // handler can catch and handle the crash. Here we assume the frame is valid.
 650 //
 651 // First letter indicates type of the frame:
 652 //    J: Java frame (compiled)
 653 //    j: Java frame (interpreted)
 654 //    A: Java frame (AOT compiled and loaded after class initialization)
 655 //    P: Java frame (AOT compiled and preloaded before class initialization)
 656 //    V: VM frame (C/C++)
 657 //    v: Other frames running VM generated code (e.g. stubs, adapters, etc.)
 658 //    C: C/C++ frame
 659 //
 660 // We don't need detailed frame type as that in frame::print_name(). "C"
 661 // suggests the problem is in user lib; everything else is likely a VM bug.
 662 
 663 void frame::print_on_error(outputStream* st, char* buf, int buflen, bool verbose) const {
 664   if (_cb != nullptr) {
 665     if (Interpreter::contains(pc())) {
 666       Method* m = this->interpreter_frame_method();
 667       if (m != nullptr) {
 668         m->name_and_sig_as_C_string(buf, buflen);
 669         st->print("j  %s", buf);
 670         st->print("+%d", this->interpreter_frame_bci());
 671         ModuleEntry* module = m->method_holder()->module();
 672         if (module->is_named()) {
 673           module->name()->as_C_string(buf, buflen);
 674           st->print(" %s", buf);
 675           if (module->version() != nullptr) {
 676             module->version()->as_C_string(buf, buflen);
 677             st->print("@%s", buf);
 678           }
 679         }
 680       } else {
 681         st->print("j  " PTR_FORMAT, p2i(pc()));
 682       }
 683     } else if (StubRoutines::contains(pc())) {
 684       StubCodeDesc* desc = StubCodeDesc::desc_for(pc());
 685       if (desc != nullptr) {
 686         st->print("v  ~StubRoutines::%s " PTR_FORMAT, desc->name(), p2i(pc()));
 687       } else {
 688         st->print("v  ~StubRoutines::" PTR_FORMAT, p2i(pc()));
 689       }
 690     } else if (_cb->is_buffer_blob()) {
 691       st->print("v  ~BufferBlob::%s " PTR_FORMAT, ((BufferBlob *)_cb)->name(), p2i(pc()));
 692     } else if (_cb->is_nmethod()) {
 693       nmethod* nm = _cb->as_nmethod();
 694       Method* m = nm->method();
 695       if (m != nullptr) {
 696         st->print("%s", (nm->preloaded() ? "P" : (nm->is_aot() ? "A" : "J")));
 697         st->print(" %d%s", nm->compile_id(), (nm->is_osr_method() ? "%" : ""));
 698         st->print(" %s", nm->compiler_name());
 699         m->name_and_sig_as_C_string(buf, buflen);
 700         st->print(" %s", buf);
 701         ModuleEntry* module = m->method_holder()->module();
 702         if (module->is_named()) {
 703           module->name()->as_C_string(buf, buflen);
 704           st->print(" %s", buf);
 705           if (module->version() != nullptr) {
 706             module->version()->as_C_string(buf, buflen);
 707             st->print("@%s", buf);
 708           }
 709         }
 710         st->print(" (%d bytes) @ " PTR_FORMAT " [" PTR_FORMAT "+" INTPTR_FORMAT "]",
 711                   m->code_size(), p2i(_pc), p2i(_cb->code_begin()), _pc - _cb->code_begin());
 712 #if INCLUDE_JVMCI
 713         const char* jvmciName = nm->jvmci_name();
 714         if (jvmciName != nullptr) {
 715           st->print(" (%s)", jvmciName);
 716         }
 717 #endif
 718       } else {
 719         st->print("J  " PTR_FORMAT, p2i(pc()));
 720       }
 721     } else if (_cb->is_runtime_stub()) {
 722       st->print("v  ~RuntimeStub::%s " PTR_FORMAT, ((RuntimeStub *)_cb)->name(), p2i(pc()));
 723     } else if (_cb->is_deoptimization_stub()) {
 724       st->print("v  ~DeoptimizationBlob " PTR_FORMAT, p2i(pc()));
 725     } else if (_cb->is_exception_stub()) {
 726       st->print("v  ~ExceptionBlob " PTR_FORMAT, p2i(pc()));
 727     } else if (_cb->is_safepoint_stub()) {
 728       st->print("v  ~SafepointBlob " PTR_FORMAT, p2i(pc()));
 729     } else if (_cb->is_adapter_blob()) {
 730       st->print("v  ~AdapterBlob " PTR_FORMAT, p2i(pc()));
 731     } else if (_cb->is_vtable_blob()) {
 732       st->print("v  ~VtableBlob " PTR_FORMAT, p2i(pc()));
 733     } else if (_cb->is_method_handles_adapter_blob()) {
 734       st->print("v  ~MethodHandlesAdapterBlob " PTR_FORMAT, p2i(pc()));
 735     } else if (_cb->is_uncommon_trap_stub()) {
 736       st->print("v  ~UncommonTrapBlob " PTR_FORMAT, p2i(pc()));
 737     } else if (_cb->is_upcall_stub()) {
 738       st->print("v  ~UpcallStub::%s " PTR_FORMAT, _cb->name(), p2i(pc()));
 739     } else {
 740       st->print("v  blob " PTR_FORMAT, p2i(pc()));
 741     }
 742   } else {
 743     print_C_frame(st, buf, buflen, pc());
 744   }
 745 }
 746 
 747 
 748 /*
 749   The interpreter_frame_expression_stack_at method in the case of SPARC needs the
 750   max_stack value of the method in order to compute the expression stack address.
 751   It uses the Method* in order to get the max_stack value but during GC this
 752   Method* value saved on the frame is changed by reverse_and_push and hence cannot
 753   be used. So we save the max_stack value in the FrameClosure object and pass it
 754   down to the interpreter_frame_expression_stack_at method
 755 */
 756 class InterpreterFrameClosure : public OffsetClosure {
 757  private:
 758   const frame* _fr;
 759   OopClosure*  _f;
 760   int          _max_locals;
 761   int          _max_stack;
 762 
 763  public:
 764   InterpreterFrameClosure(const frame* fr, int max_locals, int max_stack,
 765                           OopClosure* f) {
 766     _fr         = fr;
 767     _max_locals = max_locals;
 768     _max_stack  = max_stack;
 769     _f          = f;
 770   }
 771 
 772   void offset_do(int offset) {
 773     oop* addr;
 774     if (offset < _max_locals) {
 775       addr = (oop*) _fr->interpreter_frame_local_at(offset);
 776       assert((intptr_t*)addr >= _fr->sp(), "must be inside the frame");
 777       _f->do_oop(addr);
 778     } else {
 779       addr = (oop*) _fr->interpreter_frame_expression_stack_at((offset - _max_locals));
 780       // In case of exceptions, the expression stack is invalid and the esp will be reset to express
 781       // this condition. Therefore, we call f only if addr is 'inside' the stack (i.e., addr >= esp for Intel).
 782       bool in_stack;
 783       if (frame::interpreter_frame_expression_stack_direction() > 0) {
 784         in_stack = (intptr_t*)addr <= _fr->interpreter_frame_tos_address();
 785       } else {
 786         in_stack = (intptr_t*)addr >= _fr->interpreter_frame_tos_address();
 787       }
 788       if (in_stack) {
 789         _f->do_oop(addr);
 790       }
 791     }
 792   }
 793 };
 794 
 795 
 796 class InterpretedArgumentOopFinder: public SignatureIterator {
 797  private:
 798   OopClosure*  _f;             // Closure to invoke
 799   int          _offset;        // TOS-relative offset, decremented with each argument
 800   bool         _has_receiver;  // true if the callee has a receiver
 801   const frame* _fr;
 802 
 803   friend class SignatureIterator;  // so do_parameters_on can call do_type
 804   void do_type(BasicType type) {
 805     _offset -= parameter_type_word_count(type);
 806     if (is_reference_type(type)) oop_offset_do();
 807    }
 808 
 809   void oop_offset_do() {
 810     oop* addr;
 811     addr = (oop*)_fr->interpreter_frame_tos_at(_offset);
 812     _f->do_oop(addr);
 813   }
 814 
 815  public:
 816   InterpretedArgumentOopFinder(Symbol* signature, bool has_receiver, const frame* fr, OopClosure* f) : SignatureIterator(signature), _has_receiver(has_receiver) {
 817     // compute size of arguments
 818     int args_size = ArgumentSizeComputer(signature).size() + (has_receiver ? 1 : 0);
 819     assert(!fr->is_interpreted_frame() ||
 820            args_size <= fr->interpreter_frame_expression_stack_size(),
 821             "args cannot be on stack anymore");
 822     // initialize InterpretedArgumentOopFinder
 823     _f         = f;
 824     _fr        = fr;
 825     _offset    = args_size;
 826   }
 827 
 828   void oops_do() {
 829     if (_has_receiver) {
 830       --_offset;
 831       oop_offset_do();
 832     }
 833     do_parameters_on(this);
 834   }
 835 };
 836 
 837 
 838 // Entry frame has following form (n arguments)
 839 //         +-----------+
 840 //   sp -> |  last arg |
 841 //         +-----------+
 842 //         :    :::    :
 843 //         +-----------+
 844 // (sp+n)->|  first arg|
 845 //         +-----------+
 846 
 847 
 848 
 849 // visits and GC's all the arguments in entry frame
 850 class EntryFrameOopFinder: public SignatureIterator {
 851  private:
 852   bool         _is_static;
 853   int          _offset;
 854   const frame* _fr;
 855   OopClosure*  _f;
 856 
 857   friend class SignatureIterator;  // so do_parameters_on can call do_type
 858   void do_type(BasicType type) {
 859     // decrement offset before processing the type
 860     _offset -= parameter_type_word_count(type);
 861     assert (_offset >= 0, "illegal offset");
 862     if (is_reference_type(type))  oop_at_offset_do(_offset);
 863  }
 864 
 865   void oop_at_offset_do(int offset) {
 866     assert (offset >= 0, "illegal offset");
 867     oop* addr = (oop*) _fr->entry_frame_argument_at(offset);
 868     _f->do_oop(addr);
 869   }
 870 
 871  public:
 872   EntryFrameOopFinder(const frame* frame, Symbol* signature, bool is_static) : SignatureIterator(signature) {
 873     _f = nullptr; // will be set later
 874     _fr = frame;
 875     _is_static = is_static;
 876     _offset = ArgumentSizeComputer(signature).size();  // pre-decremented down to zero
 877   }
 878 
 879   void arguments_do(OopClosure* f) {
 880     _f = f;
 881     if (!_is_static)  oop_at_offset_do(_offset); // do the receiver
 882     do_parameters_on(this);
 883   }
 884 
 885 };
 886 
 887 oop* frame::interpreter_callee_receiver_addr(Symbol* signature) {
 888   ArgumentSizeComputer asc(signature);
 889   int size = asc.size();
 890   return (oop *)interpreter_frame_tos_at(size);
 891 }
 892 
 893 oop frame::interpreter_callee_receiver(Symbol* signature) {
 894   return *interpreter_callee_receiver_addr(signature);
 895 }
 896 
 897 template <typename RegisterMapT>
 898 void frame::oops_interpreted_do(OopClosure* f, const RegisterMapT* map, bool query_oop_map_cache) const {
 899   assert(is_interpreted_frame(), "Not an interpreted frame");
 900   Thread *thread = Thread::current();
 901   methodHandle m (thread, interpreter_frame_method());
 902   jint      bci = interpreter_frame_bci();
 903 
 904   assert(!Universe::heap()->is_in(m()),
 905           "must be valid oop");
 906   assert(m->is_method(), "checking frame value");
 907   assert((m->is_native() && bci == 0)  ||
 908          (!m->is_native() && bci >= 0 && bci < m->code_size()),
 909          "invalid bci value");
 910 
 911   // Handle the monitor elements in the activation
 912   for (
 913     BasicObjectLock* current = interpreter_frame_monitor_end();
 914     current < interpreter_frame_monitor_begin();
 915     current = next_monitor_in_interpreter_frame(current)
 916   ) {
 917 #ifdef ASSERT
 918     interpreter_frame_verify_monitor(current);
 919 #endif
 920     current->oops_do(f);
 921   }
 922 
 923   if (m->is_native()) {
 924     f->do_oop(interpreter_frame_temp_oop_addr());
 925   }
 926 
 927   // The method pointer in the frame might be the only path to the method's
 928   // klass, and the klass needs to be kept alive while executing. The GCs
 929   // don't trace through method pointers, so the mirror of the method's klass
 930   // is installed as a GC root.
 931   f->do_oop(interpreter_frame_mirror_addr());
 932 
 933   int max_locals = m->is_native() ? m->size_of_parameters() : m->max_locals();
 934 
 935   // Process a callee's arguments if we are at a call site
 936   // (i.e., if we are at an invoke bytecode)
 937   // This is used sometimes for calling into the VM, not for another
 938   // interpreted or compiled frame.
 939   if (!m->is_native() && map != nullptr && map->include_argument_oops()) {
 940     Bytecode_invoke call = Bytecode_invoke_check(m, bci);
 941     if (call.is_valid() && interpreter_frame_expression_stack_size() > 0) {
 942       ResourceMark rm(thread);  // is this right ???
 943       Symbol* signature = call.signature();
 944       bool has_receiver = call.has_receiver();
 945       // We are at a call site & the expression stack is not empty
 946       // so we might have callee arguments we need to process.
 947       oops_interpreted_arguments_do(signature, has_receiver, f);
 948     }
 949   }
 950 
 951   InterpreterFrameClosure blk(this, max_locals, m->max_stack(), f);
 952 
 953   // process locals & expression stack
 954   InterpreterOopMap mask;
 955   if (query_oop_map_cache) {
 956     m->mask_for(m, bci, &mask);
 957   } else {
 958     OopMapCache::compute_one_oop_map(m, bci, &mask);
 959   }
 960   mask.iterate_oop(&blk);
 961 }
 962 
 963 template void frame::oops_interpreted_do(OopClosure* f, const RegisterMap* map, bool query_oop_map_cache) const;
 964 template void frame::oops_interpreted_do(OopClosure* f, const SmallRegisterMapNoArgs* map, bool query_oop_map_cache) const;
 965 template void frame::oops_interpreted_do(OopClosure* f, const SmallRegisterMapWithArgs* map, bool query_oop_map_cache) const;
 966 
 967 void frame::oops_interpreted_arguments_do(Symbol* signature, bool has_receiver, OopClosure* f) const {
 968   InterpretedArgumentOopFinder finder(signature, has_receiver, this, f);
 969   finder.oops_do();
 970 }
 971 
 972 void frame::oops_nmethod_do(OopClosure* f, NMethodClosure* cf, DerivedOopClosure* df, DerivedPointerIterationMode derived_mode, const RegisterMap* reg_map) const {
 973   assert(_cb != nullptr, "sanity check");
 974   assert((oop_map() == nullptr) == (_cb->oop_maps() == nullptr), "frame and _cb must agree that oopmap is set or not");
 975   if (oop_map() != nullptr) {
 976     if (df != nullptr) {
 977       _oop_map->oops_do(this, reg_map, f, df);
 978     } else {
 979       _oop_map->oops_do(this, reg_map, f, derived_mode);
 980     }
 981 
 982     // Preserve potential arguments for a callee. We handle this by dispatching
 983     // on the codeblob. For c2i, we do
 984     if (reg_map->include_argument_oops() && _cb->is_nmethod()) {
 985       // Only nmethod preserves outgoing arguments at call.
 986       _cb->as_nmethod()->preserve_callee_argument_oops(*this, reg_map, f);
 987     }
 988   }
 989   // In cases where perm gen is collected, GC will want to mark
 990   // oops referenced from nmethods active on thread stacks so as to
 991   // prevent them from being collected. However, this visit should be
 992   // restricted to certain phases of the collection only. The
 993   // closure decides how it wants nmethods to be traced.
 994   if (cf != nullptr && _cb->is_nmethod())
 995     cf->do_nmethod(_cb->as_nmethod());
 996 }
 997 
 998 class CompiledArgumentOopFinder: public SignatureIterator {
 999  protected:
1000   OopClosure*     _f;
1001   int             _offset;        // the current offset, incremented with each argument
1002   bool            _has_receiver;  // true if the callee has a receiver
1003   bool            _has_appendix;  // true if the call has an appendix
1004   frame           _fr;
1005   RegisterMap*    _reg_map;
1006   int             _arg_size;
1007   VMRegPair*      _regs;        // VMReg list of arguments
1008 
1009   friend class SignatureIterator;  // so do_parameters_on can call do_type
1010   void do_type(BasicType type) {
1011     if (is_reference_type(type))  handle_oop_offset();
1012     _offset += parameter_type_word_count(type);
1013   }
1014 
1015   virtual void handle_oop_offset() {
1016     // Extract low order register number from register array.
1017     // In LP64-land, the high-order bits are valid but unhelpful.
1018     VMReg reg = _regs[_offset].first();
1019     oop *loc = _fr.oopmapreg_to_oop_location(reg, _reg_map);
1020   #ifdef ASSERT
1021     if (loc == nullptr) {
1022       if (_reg_map->should_skip_missing()) {
1023         return;
1024       }
1025       tty->print_cr("Error walking frame oops:");
1026       _fr.print_on(tty);
1027       assert(loc != nullptr, "missing register map entry reg: %d %s loc: " INTPTR_FORMAT, reg->value(), reg->name(), p2i(loc));
1028     }
1029   #endif
1030     _f->do_oop(loc);
1031   }
1032 
1033  public:
1034   CompiledArgumentOopFinder(Symbol* signature, bool has_receiver, bool has_appendix, OopClosure* f, frame fr, const RegisterMap* reg_map)
1035     : SignatureIterator(signature) {
1036 
1037     // initialize CompiledArgumentOopFinder
1038     _f         = f;
1039     _offset    = 0;
1040     _has_receiver = has_receiver;
1041     _has_appendix = has_appendix;
1042     _fr        = fr;
1043     _reg_map   = (RegisterMap*)reg_map;
1044     _arg_size  = ArgumentSizeComputer(signature).size() + (has_receiver ? 1 : 0) + (has_appendix ? 1 : 0);
1045 
1046     int arg_size;
1047     _regs = SharedRuntime::find_callee_arguments(signature, has_receiver, has_appendix, &arg_size);
1048     assert(arg_size == _arg_size, "wrong arg size");
1049   }
1050 
1051   void oops_do() {
1052     if (_has_receiver) {
1053       handle_oop_offset();
1054       _offset++;
1055     }
1056     do_parameters_on(this);
1057     if (_has_appendix) {
1058       handle_oop_offset();
1059       _offset++;
1060     }
1061   }
1062 };
1063 
1064 void frame::oops_compiled_arguments_do(Symbol* signature, bool has_receiver, bool has_appendix,
1065                                        const RegisterMap* reg_map, OopClosure* f) const {
1066   // ResourceMark rm;
1067   CompiledArgumentOopFinder finder(signature, has_receiver, has_appendix, f, *this, reg_map);
1068   finder.oops_do();
1069 }
1070 
1071 // Get receiver out of callers frame, i.e. find parameter 0 in callers
1072 // frame.  Consult ADLC for where parameter 0 is to be found.  Then
1073 // check local reg_map for it being a callee-save register or argument
1074 // register, both of which are saved in the local frame.  If not found
1075 // there, it must be an in-stack argument of the caller.
1076 // Note: caller.sp() points to callee-arguments
1077 oop frame::retrieve_receiver(RegisterMap* reg_map) {
1078   frame caller = *this;
1079 
1080   // First consult the ADLC on where it puts parameter 0 for this signature.
1081   VMReg reg = SharedRuntime::name_for_receiver();
1082   oop* oop_adr = caller.oopmapreg_to_oop_location(reg, reg_map);
1083   if (oop_adr == nullptr) {
1084     guarantee(oop_adr != nullptr, "bad register save location");
1085     return nullptr;
1086   }
1087   oop r = *oop_adr;
1088   assert(Universe::heap()->is_in_or_null(r), "bad receiver: " INTPTR_FORMAT " (%zd)", p2i(r), p2i(r));
1089   return r;
1090 }
1091 
1092 
1093 BasicLock* frame::get_native_monitor() const {
1094   nmethod* nm = (nmethod*)_cb;
1095   assert(_cb != nullptr && _cb->is_nmethod() && nm->method()->is_native(),
1096          "Should not call this unless it's a native nmethod");
1097   int byte_offset = in_bytes(nm->native_basic_lock_sp_offset());
1098   assert(byte_offset >= 0, "should not see invalid offset");
1099   return (BasicLock*) &sp()[byte_offset / wordSize];
1100 }
1101 
1102 oop frame::get_native_receiver() const {
1103   nmethod* nm = (nmethod*)_cb;
1104   assert(_cb != nullptr && _cb->is_nmethod() && nm->method()->is_native(),
1105          "Should not call this unless it's a native nmethod");
1106   int byte_offset = in_bytes(nm->native_receiver_sp_offset());
1107   assert(byte_offset >= 0, "should not see invalid offset");
1108   oop owner = ((oop*) sp())[byte_offset / wordSize];
1109   assert( Universe::heap()->is_in(owner), "bad receiver" );
1110   return owner;
1111 }
1112 
1113 void frame::oops_entry_do(OopClosure* f, const RegisterMap* map) const {
1114   assert(map != nullptr, "map must be set");
1115   if (map->include_argument_oops()) {
1116     // must collect argument oops, as nobody else is doing it
1117     Thread *thread = Thread::current();
1118     methodHandle m (thread, entry_frame_call_wrapper()->callee_method());
1119     EntryFrameOopFinder finder(this, m->signature(), m->is_static());
1120     finder.arguments_do(f);
1121   }
1122   // Traverse the Handle Block saved in the entry frame
1123   entry_frame_call_wrapper()->oops_do(f);
1124 }
1125 
1126 void frame::oops_upcall_do(OopClosure* f, const RegisterMap* map) const {
1127   assert(map != nullptr, "map must be set");
1128   if (map->include_argument_oops()) {
1129     // Upcall stubs call a MethodHandle impl method of which only the receiver
1130     // is ever an oop.
1131     // Currently we should not be able to get here, since there are no
1132     // safepoints in the one resolve stub we can get into (handle_wrong_method)
1133     // Leave this here as a trap in case we ever do:
1134     ShouldNotReachHere(); // not implemented
1135   }
1136   _cb->as_upcall_stub()->oops_do(f, *this);
1137 }
1138 
1139 bool frame::is_deoptimized_frame() const {
1140   assert(_deopt_state != unknown, "not answerable");
1141   if (_deopt_state == is_deoptimized) {
1142     return true;
1143   }
1144 
1145   /* This method only checks if the frame is deoptimized
1146    * as in return address being patched.
1147    * It doesn't care if the OP that we return to is a
1148    * deopt instruction */
1149   /*if (_cb != nullptr && _cb->is_nmethod()) {
1150     return NativeDeoptInstruction::is_deopt_at(_pc);
1151   }*/
1152   return false;
1153 }
1154 
1155 void frame::oops_do_internal(OopClosure* f, NMethodClosure* cf,
1156                              DerivedOopClosure* df, DerivedPointerIterationMode derived_mode,
1157                              const RegisterMap* map, bool use_interpreter_oop_map_cache) const {
1158 #ifndef PRODUCT
1159   // simulate GC crash here to dump java thread in error report
1160   guarantee(!CrashGCForDumpingJavaThread, "");
1161 #endif
1162   if (is_interpreted_frame()) {
1163     oops_interpreted_do(f, map, use_interpreter_oop_map_cache);
1164   } else if (is_entry_frame()) {
1165     oops_entry_do(f, map);
1166   } else if (is_upcall_stub_frame()) {
1167     oops_upcall_do(f, map);
1168   } else if (CodeCache::contains(pc())) {
1169     oops_nmethod_do(f, cf, df, derived_mode, map);
1170   } else {
1171     ShouldNotReachHere();
1172   }
1173 }
1174 
1175 void frame::nmethod_do(NMethodClosure* cf) const {
1176   if (_cb != nullptr && _cb->is_nmethod()) {
1177     cf->do_nmethod(_cb->as_nmethod());
1178   }
1179 }
1180 
1181 
1182 // Call f closure on the interpreted Method*s in the stack.
1183 void frame::metadata_do(MetadataClosure* f) const {
1184   ResourceMark rm;
1185   if (is_interpreted_frame()) {
1186     Method* m = this->interpreter_frame_method();
1187     assert(m != nullptr, "expecting a method in this frame");
1188     f->do_metadata(m);
1189   }
1190 }
1191 
1192 void frame::verify(const RegisterMap* map) const {
1193 #ifndef PRODUCT
1194   if (TraceCodeBlobStacks) {
1195     tty->print_cr("*** verify");
1196     print_on(tty);
1197   }
1198 #endif
1199 
1200   // for now make sure receiver type is correct
1201   if (is_interpreted_frame()) {
1202     Method* method = interpreter_frame_method();
1203     guarantee(method->is_method(), "method is wrong in frame::verify");
1204     if (!method->is_static()) {
1205       // fetch the receiver
1206       oop* p = (oop*) interpreter_frame_local_at(0);
1207       // make sure we have the right receiver type
1208     }
1209   }
1210 #if COMPILER2_OR_JVMCI
1211   assert(DerivedPointerTable::is_empty(), "must be empty before verify");
1212 #endif
1213 
1214   if (map->update_map()) { // The map has to be up-to-date for the current frame
1215     oops_do_internal(&VerifyOopClosure::verify_oop, nullptr, nullptr, DerivedPointerIterationMode::_ignore, map, false);
1216   }
1217 }
1218 
1219 
1220 #ifdef ASSERT
1221 bool frame::verify_return_pc(address x) {
1222 #ifdef TARGET_ARCH_aarch64
1223   if (!pauth_ptr_is_raw(x)) {
1224     return false;
1225   }
1226 #endif
1227   if (StubRoutines::returns_to_call_stub(x)) {
1228     return true;
1229   }
1230   if (CodeCache::contains(x)) {
1231     return true;
1232   }
1233   if (Interpreter::contains(x)) {
1234     return true;
1235   }
1236   return false;
1237 }
1238 #endif
1239 
1240 #ifdef ASSERT
1241 void frame::interpreter_frame_verify_monitor(BasicObjectLock* value) const {
1242   assert(is_interpreted_frame(), "Not an interpreted frame");
1243   // verify that the value is in the right part of the frame
1244   address low_mark  = (address) interpreter_frame_monitor_end();
1245   address high_mark = (address) interpreter_frame_monitor_begin();
1246   address current   = (address) value;
1247 
1248   const int monitor_size = frame::interpreter_frame_monitor_size();
1249   guarantee((high_mark - current) % monitor_size  ==  0         , "Misaligned top of BasicObjectLock*");
1250   guarantee( high_mark > current                                , "Current BasicObjectLock* higher than high_mark");
1251 
1252   guarantee((current - low_mark) % monitor_size  ==  0         , "Misaligned bottom of BasicObjectLock*");
1253   guarantee( current >= low_mark                               , "Current BasicObjectLock* below than low_mark");
1254 }
1255 #endif
1256 
1257 #ifndef PRODUCT
1258 
1259 // Returns true iff the address p is readable and *(intptr_t*)p != errvalue
1260 extern "C" bool dbg_is_safe(const void* p, intptr_t errvalue);
1261 
1262 class FrameValuesOopClosure: public OopClosure, public DerivedOopClosure {
1263 private:
1264   GrowableArray<oop*>* _oops;
1265   GrowableArray<narrowOop*>* _narrow_oops;
1266   GrowableArray<derived_base*>* _base;
1267   GrowableArray<derived_pointer*>* _derived;
1268   NoSafepointVerifier nsv;
1269 
1270 public:
1271   FrameValuesOopClosure() {
1272     _oops = new (mtThread) GrowableArray<oop*>(100, mtThread);
1273     _narrow_oops = new (mtThread) GrowableArray<narrowOop*>(100, mtThread);
1274     _base = new (mtThread) GrowableArray<derived_base*>(100, mtThread);
1275     _derived = new (mtThread) GrowableArray<derived_pointer*>(100, mtThread);
1276   }
1277   ~FrameValuesOopClosure() {
1278     delete _oops;
1279     delete _narrow_oops;
1280     delete _base;
1281     delete _derived;
1282   }
1283 
1284   virtual void do_oop(oop* p) override { _oops->push(p); }
1285   virtual void do_oop(narrowOop* p) override { _narrow_oops->push(p); }
1286   virtual void do_derived_oop(derived_base* base_loc, derived_pointer* derived_loc) override {
1287     _base->push(base_loc);
1288     _derived->push(derived_loc);
1289   }
1290 
1291   bool is_good(oop* p) {
1292     return *p == nullptr || (dbg_is_safe(*p, -1) && dbg_is_safe((*p)->klass(), -1) && oopDesc::is_oop_or_null(*p));
1293   }
1294   void describe(FrameValues& values, int frame_no) {
1295     for (int i = 0; i < _oops->length(); i++) {
1296       oop* p = _oops->at(i);
1297       values.describe(frame_no, (intptr_t*)p, err_msg("oop%s for #%d", is_good(p) ? "" : " (BAD)", frame_no));
1298     }
1299     for (int i = 0; i < _narrow_oops->length(); i++) {
1300       narrowOop* p = _narrow_oops->at(i);
1301       // we can't check for bad compressed oops, as decoding them might crash
1302       values.describe(frame_no, (intptr_t*)p, err_msg("narrow oop for #%d", frame_no));
1303     }
1304     assert(_base->length() == _derived->length(), "should be the same");
1305     for (int i = 0; i < _base->length(); i++) {
1306       derived_base* base = _base->at(i);
1307       derived_pointer* derived = _derived->at(i);
1308       values.describe(frame_no, (intptr_t*)derived, err_msg("derived pointer (base: " INTPTR_FORMAT ") for #%d", p2i(base), frame_no));
1309     }
1310   }
1311 };
1312 
1313 class FrameValuesOopMapClosure: public OopMapClosure {
1314 private:
1315   const frame* _fr;
1316   const RegisterMap* _reg_map;
1317   FrameValues& _values;
1318   int _frame_no;
1319 
1320 public:
1321   FrameValuesOopMapClosure(const frame* fr, const RegisterMap* reg_map, FrameValues& values, int frame_no)
1322    : _fr(fr), _reg_map(reg_map), _values(values), _frame_no(frame_no) {}
1323 
1324   virtual void do_value(VMReg reg, OopMapValue::oop_types type) override {
1325     intptr_t* p = (intptr_t*)_fr->oopmapreg_to_location(reg, _reg_map);
1326     if (p != nullptr && (((intptr_t)p & WordAlignmentMask) == 0)) {
1327       const char* type_name = nullptr;
1328       switch(type) {
1329         case OopMapValue::oop_value:          type_name = "oop";          break;
1330         case OopMapValue::narrowoop_value:    type_name = "narrow oop";   break;
1331         case OopMapValue::callee_saved_value: type_name = "callee-saved"; break;
1332         case OopMapValue::derived_oop_value:  type_name = "derived";      break;
1333         // case OopMapValue::live_value:         type_name = "live";         break;
1334         default: break;
1335       }
1336       if (type_name != nullptr) {
1337         _values.describe(_frame_no, p, err_msg("%s for #%d", type_name, _frame_no));
1338       }
1339     }
1340   }
1341 };
1342 
1343 // callers need a ResourceMark because of name_and_sig_as_C_string() usage,
1344 // RA allocated string is returned to the caller
1345 void frame::describe(FrameValues& values, int frame_no, const RegisterMap* reg_map, bool top) {
1346   // boundaries: sp and the 'real' frame pointer
1347   values.describe(-1, sp(), err_msg("sp for #%d", frame_no), 0);
1348   if (top) {
1349     values.describe(-1, sp() - 1, err_msg("sp[-1] for #%d", frame_no), 0);
1350     values.describe(-1, sp() - 2, err_msg("sp[-2] for #%d", frame_no), 0);
1351   }
1352 
1353   intptr_t* frame_pointer = real_fp(); // Note: may differ from fp()
1354 
1355   // print frame info at the highest boundary
1356   intptr_t* info_address = MAX2(sp(), frame_pointer);
1357 
1358   if (info_address != frame_pointer) {
1359     // print frame_pointer explicitly if not marked by the frame info
1360     values.describe(-1, frame_pointer, err_msg("frame pointer for #%d", frame_no), 1);
1361   }
1362 
1363   if (is_entry_frame() || is_compiled_frame() || is_interpreted_frame() || is_native_frame()) {
1364     // Label values common to most frames
1365     values.describe(-1, unextended_sp(), err_msg("unextended_sp for #%d", frame_no), 0);
1366   }
1367 
1368   if (is_interpreted_frame()) {
1369     Method* m = interpreter_frame_method();
1370     int bci = interpreter_frame_bci();
1371     InterpreterCodelet* desc = Interpreter::codelet_containing(pc());
1372 
1373     // Label the method and current bci
1374     values.describe(-1, info_address,
1375                     FormatBuffer<1024>("#%d method %s @ %d", frame_no, m->name_and_sig_as_C_string(), bci), 3);
1376     if (desc != nullptr) {
1377       values.describe(-1, info_address, err_msg("- %s codelet: %s",
1378         desc->bytecode()    >= 0    ? Bytecodes::name(desc->bytecode()) : "",
1379         desc->description() != nullptr ? desc->description()               : "?"), 2);
1380     }
1381     values.describe(-1, info_address,
1382                     err_msg("- %d locals %d max stack", m->max_locals(), m->max_stack()), 2);
1383     // return address will be emitted by caller in describe_pd
1384     // values.describe(frame_no, (intptr_t*)sender_pc_addr(), Continuation::is_return_barrier_entry(*sender_pc_addr()) ? "return address (return barrier)" : "return address");
1385 
1386     if (m->max_locals() > 0) {
1387       intptr_t* l0 = interpreter_frame_local_at(0);
1388       intptr_t* ln = interpreter_frame_local_at(m->max_locals() - 1);
1389       values.describe(-1, MAX2(l0, ln), err_msg("locals for #%d", frame_no), 2);
1390       // Report each local and mark as owned by this frame
1391       for (int l = 0; l < m->max_locals(); l++) {
1392         intptr_t* l0 = interpreter_frame_local_at(l);
1393         values.describe(frame_no, l0, err_msg("local %d", l), 1);
1394       }
1395     }
1396 
1397     if (interpreter_frame_monitor_begin() != interpreter_frame_monitor_end()) {
1398       values.describe(frame_no, (intptr_t*)interpreter_frame_monitor_begin(), "monitors begin");
1399       values.describe(frame_no, (intptr_t*)interpreter_frame_monitor_end(), "monitors end");
1400     }
1401 
1402     // Compute the actual expression stack size
1403     InterpreterOopMap mask;
1404     OopMapCache::compute_one_oop_map(methodHandle(Thread::current(), m), bci, &mask);
1405     intptr_t* tos = nullptr;
1406     // Report each stack element and mark as owned by this frame
1407     for (int e = 0; e < mask.expression_stack_size(); e++) {
1408       tos = MAX2(tos, interpreter_frame_expression_stack_at(e));
1409       values.describe(frame_no, interpreter_frame_expression_stack_at(e),
1410                       err_msg("stack %d", e), 1);
1411     }
1412     if (tos != nullptr) {
1413       values.describe(-1, tos, err_msg("expression stack for #%d", frame_no), 2);
1414     }
1415 
1416     if (reg_map != nullptr) {
1417       FrameValuesOopClosure oopsFn;
1418       oops_do(&oopsFn, nullptr, &oopsFn, reg_map);
1419       oopsFn.describe(values, frame_no);
1420     }
1421   } else if (is_entry_frame()) {
1422     // For now just label the frame
1423     values.describe(-1, info_address, err_msg("#%d entry frame", frame_no), 2);
1424   } else if (is_compiled_frame()) {
1425     // For now just label the frame
1426     nmethod* nm = cb()->as_nmethod();
1427     values.describe(-1, info_address,
1428                     FormatBuffer<1024>("#%d nmethod " INTPTR_FORMAT " for method J %s%s", frame_no,
1429                                        p2i(nm),
1430                                        nm->method()->name_and_sig_as_C_string(),
1431                                        (_deopt_state == is_deoptimized) ?
1432                                        " (deoptimized)" :
1433                                        ((_deopt_state == unknown) ? " (state unknown)" : "")),
1434                     3);
1435 
1436     { // mark arguments (see nmethod::print_nmethod_labels)
1437       Method* m = nm->method();
1438 
1439       int stack_slot_offset = nm->frame_size() * wordSize; // offset, in bytes, to caller sp
1440       int sizeargs = m->size_of_parameters();
1441 
1442       BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
1443       VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
1444       {
1445         int sig_index = 0;
1446         if (!m->is_static()) {
1447           sig_bt[sig_index++] = T_OBJECT; // 'this'
1448         }
1449         for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
1450           BasicType t = ss.type();
1451           assert(type2size[t] == 1 || type2size[t] == 2, "size is 1 or 2");
1452           sig_bt[sig_index++] = t;
1453           if (type2size[t] == 2) {
1454             sig_bt[sig_index++] = T_VOID;
1455           }
1456         }
1457         assert(sig_index == sizeargs, "");
1458       }
1459       int stack_arg_slots = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs);
1460       assert(stack_arg_slots ==  nm->as_nmethod()->num_stack_arg_slots(false /* rounded */) || nm->is_osr_method(), "");
1461       int out_preserve = SharedRuntime::out_preserve_stack_slots();
1462       int sig_index = 0;
1463       int arg_index = (m->is_static() ? 0 : -1);
1464       for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
1465         bool at_this = (arg_index == -1);
1466         bool at_old_sp = false;
1467         BasicType t = (at_this ? T_OBJECT : ss.type());
1468         assert(t == sig_bt[sig_index], "sigs in sync");
1469         VMReg fst = regs[sig_index].first();
1470         if (fst->is_stack()) {
1471           assert(((int)fst->reg2stack()) >= 0, "reg2stack: %d", fst->reg2stack());
1472           int offset = (fst->reg2stack() + out_preserve) * VMRegImpl::stack_slot_size + stack_slot_offset;
1473           intptr_t* stack_address = (intptr_t*)((address)unextended_sp() + offset);
1474           if (at_this) {
1475             values.describe(frame_no, stack_address, err_msg("this for #%d", frame_no), 1);
1476           } else {
1477             values.describe(frame_no, stack_address, err_msg("param %d %s for #%d", arg_index, type2name(t), frame_no), 1);
1478           }
1479         }
1480         sig_index += type2size[t];
1481         arg_index += 1;
1482         if (!at_this) {
1483           ss.next();
1484         }
1485       }
1486     }
1487 
1488     if (reg_map != nullptr && is_java_frame()) {
1489       int scope_no = 0;
1490       for (ScopeDesc* scope = nm->scope_desc_at(pc()); scope != nullptr; scope = scope->sender(), scope_no++) {
1491         Method* m = scope->method();
1492         int  bci = scope->bci();
1493         values.describe(-1, info_address, err_msg("- #%d scope %s @ %d", scope_no, m->name_and_sig_as_C_string(), bci), 2);
1494 
1495         { // mark locals
1496           GrowableArray<ScopeValue*>* scvs = scope->locals();
1497           int scvs_length = scvs != nullptr ? scvs->length() : 0;
1498           for (int i = 0; i < scvs_length; i++) {
1499             intptr_t* stack_address = (intptr_t*)StackValue::stack_value_address(this, reg_map, scvs->at(i));
1500             if (stack_address != nullptr) {
1501               values.describe(frame_no, stack_address, err_msg("local %d for #%d (scope %d)", i, frame_no, scope_no), 1);
1502             }
1503           }
1504         }
1505         { // mark expression stack
1506           GrowableArray<ScopeValue*>* scvs = scope->expressions();
1507           int scvs_length = scvs != nullptr ? scvs->length() : 0;
1508           for (int i = 0; i < scvs_length; i++) {
1509             intptr_t* stack_address = (intptr_t*)StackValue::stack_value_address(this, reg_map, scvs->at(i));
1510             if (stack_address != nullptr) {
1511               values.describe(frame_no, stack_address, err_msg("stack %d for #%d (scope %d)", i, frame_no, scope_no), 1);
1512             }
1513           }
1514         }
1515       }
1516 
1517       FrameValuesOopClosure oopsFn;
1518       oops_do(&oopsFn, nullptr, &oopsFn, reg_map);
1519       oopsFn.describe(values, frame_no);
1520 
1521       if (oop_map() != nullptr) {
1522         FrameValuesOopMapClosure valuesFn(this, reg_map, values, frame_no);
1523         // also OopMapValue::live_value ??
1524         oop_map()->all_type_do(this, OopMapValue::callee_saved_value, &valuesFn);
1525       }
1526     }
1527   } else if (is_native_frame()) {
1528     // For now just label the frame
1529     nmethod* nm = cb()->as_nmethod_or_null();
1530     values.describe(-1, info_address,
1531                     FormatBuffer<1024>("#%d nmethod " INTPTR_FORMAT " for native method %s", frame_no,
1532                                        p2i(nm), nm->method()->name_and_sig_as_C_string()), 2);
1533     if (nm->method()->is_continuation_enter_intrinsic()) {
1534       ContinuationEntry* ce = Continuation::get_continuation_entry_for_entry_frame(reg_map->thread(), *this); // (ContinuationEntry*)unextended_sp();
1535       ce->describe(values, frame_no);
1536     }
1537   } else {
1538     // provide default info if not handled before
1539     char *info = (char *) "special frame";
1540     if ((_cb != nullptr) &&
1541         (_cb->name() != nullptr)) {
1542       info = (char *)_cb->name();
1543     }
1544     values.describe(-1, info_address, err_msg("#%d <%s>", frame_no, info), 2);
1545   }
1546 
1547   // platform dependent additional data
1548   describe_pd(values, frame_no);
1549 }
1550 
1551 #endif
1552 
1553 /**
1554  * Gets the caller frame of `fr` for thread `t`.
1555  *
1556  * @returns an invalid frame (i.e. fr.pc() === 0) if the caller cannot be obtained
1557  */
1558 frame frame::next_frame(frame fr, Thread* t) {
1559   // Compiled code may use EBP register on x86 so it looks like
1560   // non-walkable C frame. Use frame.sender() for java frames.
1561   frame invalid;
1562   if (t != nullptr && t->is_Java_thread()) {
1563     // Catch very first native frame by using stack address.
1564     // For JavaThread stack_base and stack_size should be set.
1565     if (!t->is_in_full_stack((address)(fr.real_fp() + 1))) {
1566       return invalid;
1567     }
1568     if (fr.is_interpreted_frame() || (fr.cb() != nullptr && fr.cb()->frame_size() > 0)) {
1569       RegisterMap map(JavaThread::cast(t),
1570                       RegisterMap::UpdateMap::skip,
1571                       RegisterMap::ProcessFrames::include,
1572                       RegisterMap::WalkContinuation::skip); // No update
1573       return fr.sender(&map);
1574     } else {
1575       // is_first_C_frame() does only simple checks for frame pointer,
1576       // it will pass if java compiled code has a pointer in EBP.
1577       if (os::is_first_C_frame(&fr)) return invalid;
1578       return os::get_sender_for_C_frame(&fr);
1579     }
1580   } else {
1581     if (os::is_first_C_frame(&fr)) return invalid;
1582     return os::get_sender_for_C_frame(&fr);
1583   }
1584 }
1585 
1586 #ifndef PRODUCT
1587 
1588 void FrameValues::describe(int owner, intptr_t* location, const char* description, int priority) {
1589   FrameValue fv;
1590   fv.location = location;
1591   fv.owner = owner;
1592   fv.priority = priority;
1593   fv.description = NEW_RESOURCE_ARRAY(char, strlen(description) + 1);
1594   strcpy(fv.description, description);
1595   _values.append(fv);
1596 }
1597 
1598 
1599 #ifdef ASSERT
1600 void FrameValues::validate() {
1601   _values.sort(compare);
1602   bool error = false;
1603   FrameValue prev;
1604   prev.owner = -1;
1605   for (int i = _values.length() - 1; i >= 0; i--) {
1606     FrameValue fv = _values.at(i);
1607     if (fv.owner == -1) continue;
1608     if (prev.owner == -1) {
1609       prev = fv;
1610       continue;
1611     }
1612     if (prev.location == fv.location) {
1613       if (fv.owner != prev.owner) {
1614         tty->print_cr("overlapping storage");
1615         tty->print_cr(" " INTPTR_FORMAT ": " INTPTR_FORMAT " %s", p2i(prev.location), *prev.location, prev.description);
1616         tty->print_cr(" " INTPTR_FORMAT ": " INTPTR_FORMAT " %s", p2i(fv.location), *fv.location, fv.description);
1617         error = true;
1618       }
1619     } else {
1620       prev = fv;
1621     }
1622   }
1623   // if (error) { tty->cr(); print_on(static_cast<JavaThread*>(nullptr), tty); }
1624   assert(!error, "invalid layout");
1625 }
1626 #endif // ASSERT
1627 
1628 void FrameValues::print_on(JavaThread* thread, outputStream* st) {
1629   _values.sort(compare);
1630 
1631   // Sometimes values like the fp can be invalid values if the
1632   // register map wasn't updated during the walk.  Trim out values
1633   // that aren't actually in the stack of the thread.
1634   int min_index = 0;
1635   int max_index = _values.length() - 1;
1636   intptr_t* v0 = _values.at(min_index).location;
1637   intptr_t* v1 = _values.at(max_index).location;
1638 
1639   if (thread != nullptr) {
1640     if (thread == Thread::current()) {
1641       while (!thread->is_in_live_stack((address)v0)) v0 = _values.at(++min_index).location;
1642       while (!thread->is_in_live_stack((address)v1)) v1 = _values.at(--max_index).location;
1643     } else {
1644       while (!thread->is_in_full_stack((address)v0)) v0 = _values.at(++min_index).location;
1645       while (!thread->is_in_full_stack((address)v1)) v1 = _values.at(--max_index).location;
1646     }
1647   }
1648 
1649   print_on(st, min_index, max_index, v0, v1);
1650 }
1651 
1652 void FrameValues::print_on(stackChunkOop chunk, outputStream* st) {
1653   _values.sort(compare);
1654 
1655   intptr_t* start = chunk->start_address();
1656   intptr_t* end = chunk->end_address() + 1;
1657 
1658   int min_index = 0;
1659   int max_index = _values.length() - 1;
1660   intptr_t* v0 = _values.at(min_index).location;
1661   intptr_t* v1 = _values.at(max_index).location;
1662   while (!(start <= v0 && v0 <= end)) v0 = _values.at(++min_index).location;
1663   while (!(start <= v1 && v1 <= end)) v1 = _values.at(--max_index).location;
1664 
1665   print_on(st, min_index, max_index, v0, v1);
1666 }
1667 
1668 void FrameValues::print_on(outputStream* st, int min_index, int max_index, intptr_t* v0, intptr_t* v1) {
1669   intptr_t* min = MIN2(v0, v1);
1670   intptr_t* max = MAX2(v0, v1);
1671   intptr_t* cur = max;
1672   intptr_t* last = nullptr;
1673   intptr_t* fp = nullptr;
1674   for (int i = max_index; i >= min_index; i--) {
1675     FrameValue fv = _values.at(i);
1676     while (cur > fv.location) {
1677       st->print_cr(" " INTPTR_FORMAT ": " INTPTR_FORMAT, p2i(cur), *cur);
1678       cur--;
1679     }
1680     if (last == fv.location) {
1681       const char* spacer = "          " LP64_ONLY("        ");
1682       st->print_cr(" %s  %s %s", spacer, spacer, fv.description);
1683     } else {
1684       if (*fv.description == '#' && isdigit(fv.description[1])) {
1685         // The fv.description string starting with a '#' is the line for the
1686         // saved frame pointer eg. "#10 method java.lang.invoke.LambdaForm..."
1687         // basicaly means frame 10.
1688         fp = fv.location;
1689       }
1690       // To print a fp-relative value:
1691       //   1. The content of *fv.location must be such that we think it's a
1692       //      fp-relative number, i.e [-100..100].
1693       //   2. We must have found the frame pointer.
1694       //   3. The line can not be the line for the saved frame pointer.
1695       //   4. Recognize it as being part of the "fixed frame".
1696       if (*fv.location != 0 && *fv.location > -100 && *fv.location < 100
1697           && fp != nullptr && *fv.description != '#'
1698 #if !defined(PPC64)
1699           && (strncmp(fv.description, "interpreter_frame_", 18) == 0 || strstr(fv.description, " method "))
1700 #else  // !defined(PPC64)
1701           && (strcmp(fv.description, "sender_sp") == 0 || strcmp(fv.description, "top_frame_sp") == 0 ||
1702               strcmp(fv.description, "esp") == 0 || strcmp(fv.description, "monitors") == 0 ||
1703               strcmp(fv.description, "locals") == 0 || strstr(fv.description, " method "))
1704 #endif //!defined(PPC64)
1705           ) {
1706         st->print_cr(" " INTPTR_FORMAT ": " INTPTR_FORMAT " %-32s (relativized: fp%+d)",
1707                      p2i(fv.location), p2i(&fp[*fv.location]), fv.description, (int)*fv.location);
1708       } else {
1709         st->print_cr(" " INTPTR_FORMAT ": " INTPTR_FORMAT " %s", p2i(fv.location), *fv.location, fv.description);
1710       }
1711       last = fv.location;
1712       cur--;
1713     }
1714   }
1715 }
1716 
1717 #endif // ndef PRODUCT