1 /*
   2  * Copyright (c) 2000, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "ci/ciMethodData.hpp"
  27 #include "classfile/vmSymbols.hpp"
  28 #include "compiler/compilationPolicy.hpp"
  29 #include "compiler/compilerDefinitions.inline.hpp"
  30 #include "compiler/compilerOracle.hpp"
  31 #include "interpreter/bytecode.hpp"
  32 #include "interpreter/bytecodeStream.hpp"
  33 #include "interpreter/linkResolver.hpp"
  34 #include "memory/metaspaceClosure.hpp"
  35 #include "memory/resourceArea.hpp"
  36 #include "oops/klass.inline.hpp"
  37 #include "oops/methodData.inline.hpp"
  38 #include "prims/jvmtiRedefineClasses.hpp"
  39 #include "runtime/atomic.hpp"
  40 #include "runtime/deoptimization.hpp"
  41 #include "runtime/handles.inline.hpp"
  42 #include "runtime/orderAccess.hpp"
  43 #include "runtime/safepointVerifiers.hpp"
  44 #include "runtime/signature.hpp"
  45 #include "utilities/align.hpp"
  46 #include "utilities/checkedCast.hpp"
  47 #include "utilities/copy.hpp"
  48 
  49 // ==================================================================
  50 // DataLayout
  51 //
  52 // Overlay for generic profiling data.
  53 
  54 // Some types of data layouts need a length field.
  55 bool DataLayout::needs_array_len(u1 tag) {
  56   return (tag == multi_branch_data_tag) || (tag == arg_info_data_tag) || (tag == parameters_type_data_tag);
  57 }
  58 
  59 // Perform generic initialization of the data.  More specific
  60 // initialization occurs in overrides of ProfileData::post_initialize.
  61 void DataLayout::initialize(u1 tag, u2 bci, int cell_count) {
  62   _header._bits = (intptr_t)0;
  63   _header._struct._tag = tag;
  64   _header._struct._bci = bci;
  65   for (int i = 0; i < cell_count; i++) {
  66     set_cell_at(i, (intptr_t)0);
  67   }
  68   if (needs_array_len(tag)) {
  69     set_cell_at(ArrayData::array_len_off_set, cell_count - 1); // -1 for header.
  70   }
  71   if (tag == call_type_data_tag) {
  72     CallTypeData::initialize(this, cell_count);
  73   } else if (tag == virtual_call_type_data_tag) {
  74     VirtualCallTypeData::initialize(this, cell_count);
  75   }
  76 }
  77 
  78 void DataLayout::clean_weak_klass_links(bool always_clean) {
  79   ResourceMark m;
  80   data_in()->clean_weak_klass_links(always_clean);
  81 }
  82 
  83 
  84 // ==================================================================
  85 // ProfileData
  86 //
  87 // A ProfileData object is created to refer to a section of profiling
  88 // data in a structured way.
  89 
  90 // Constructor for invalid ProfileData.
  91 ProfileData::ProfileData() {
  92   _data = nullptr;
  93 }
  94 
  95 char* ProfileData::print_data_on_helper(const MethodData* md) const {
  96   DataLayout* dp  = md->extra_data_base();
  97   DataLayout* end = md->args_data_limit();
  98   stringStream ss;
  99   for (;; dp = MethodData::next_extra(dp)) {
 100     assert(dp < end, "moved past end of extra data");
 101     switch(dp->tag()) {
 102     case DataLayout::speculative_trap_data_tag:
 103       if (dp->bci() == bci()) {
 104         SpeculativeTrapData* data = new SpeculativeTrapData(dp);
 105         int trap = data->trap_state();
 106         char buf[100];
 107         ss.print("trap/");
 108         data->method()->print_short_name(&ss);
 109         ss.print("(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));
 110       }
 111       break;
 112     case DataLayout::bit_data_tag:
 113       break;
 114     case DataLayout::no_tag:
 115     case DataLayout::arg_info_data_tag:
 116       return ss.as_string();
 117       break;
 118     default:
 119       fatal("unexpected tag %d", dp->tag());
 120     }
 121   }
 122   return nullptr;
 123 }
 124 
 125 void ProfileData::print_data_on(outputStream* st, const MethodData* md) const {
 126   print_data_on(st, print_data_on_helper(md));
 127 }
 128 
 129 void ProfileData::print_shared(outputStream* st, const char* name, const char* extra) const {
 130   st->print("bci: %d ", bci());
 131   st->fill_to(tab_width_one + 1);
 132   st->print("%s", name);
 133   tab(st);
 134   int trap = trap_state();
 135   if (trap != 0) {
 136     char buf[100];
 137     st->print("trap(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));
 138   }
 139   if (extra != nullptr) {
 140     st->print("%s", extra);
 141   }
 142   int flags = data()->flags();
 143   if (flags != 0) {
 144     st->print("flags(%d) ", flags);
 145   }
 146 }
 147 
 148 void ProfileData::tab(outputStream* st, bool first) const {
 149   st->fill_to(first ? tab_width_one : tab_width_two);
 150 }
 151 
 152 // ==================================================================
 153 // BitData
 154 //
 155 // A BitData corresponds to a one-bit flag.  This is used to indicate
 156 // whether a checkcast bytecode has seen a null value.
 157 
 158 
 159 void BitData::print_data_on(outputStream* st, const char* extra) const {
 160   print_shared(st, "BitData", extra);
 161   st->cr();
 162 }
 163 
 164 // ==================================================================
 165 // CounterData
 166 //
 167 // A CounterData corresponds to a simple counter.
 168 
 169 void CounterData::print_data_on(outputStream* st, const char* extra) const {
 170   print_shared(st, "CounterData", extra);
 171   st->print_cr("count(%u)", count());
 172 }
 173 
 174 // ==================================================================
 175 // JumpData
 176 //
 177 // A JumpData is used to access profiling information for a direct
 178 // branch.  It is a counter, used for counting the number of branches,
 179 // plus a data displacement, used for realigning the data pointer to
 180 // the corresponding target bci.
 181 
 182 void JumpData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 183   assert(stream->bci() == bci(), "wrong pos");
 184   int target;
 185   Bytecodes::Code c = stream->code();
 186   if (c == Bytecodes::_goto_w || c == Bytecodes::_jsr_w) {
 187     target = stream->dest_w();
 188   } else {
 189     target = stream->dest();
 190   }
 191   int my_di = mdo->dp_to_di(dp());
 192   int target_di = mdo->bci_to_di(target);
 193   int offset = target_di - my_di;
 194   set_displacement(offset);
 195 }
 196 
 197 void JumpData::print_data_on(outputStream* st, const char* extra) const {
 198   print_shared(st, "JumpData", extra);
 199   st->print_cr("taken(%u) displacement(%d)", taken(), displacement());
 200 }
 201 
 202 int TypeStackSlotEntries::compute_cell_count(Symbol* signature, bool include_receiver, int max) {
 203   // Parameter profiling include the receiver
 204   int args_count = include_receiver ? 1 : 0;
 205   ResourceMark rm;
 206   ReferenceArgumentCount rac(signature);
 207   args_count += rac.count();
 208   args_count = MIN2(args_count, max);
 209   return args_count * per_arg_cell_count;
 210 }
 211 
 212 int TypeEntriesAtCall::compute_cell_count(BytecodeStream* stream) {
 213   assert(Bytecodes::is_invoke(stream->code()), "should be invoke");
 214   assert(TypeStackSlotEntries::per_arg_count() > ReturnTypeEntry::static_cell_count(), "code to test for arguments/results broken");
 215   const methodHandle m = stream->method();
 216   int bci = stream->bci();
 217   Bytecode_invoke inv(m, bci);
 218   int args_cell = 0;
 219   if (MethodData::profile_arguments_for_invoke(m, bci)) {
 220     args_cell = TypeStackSlotEntries::compute_cell_count(inv.signature(), false, TypeProfileArgsLimit);
 221   }
 222   int ret_cell = 0;
 223   if (MethodData::profile_return_for_invoke(m, bci) && is_reference_type(inv.result_type())) {
 224     ret_cell = ReturnTypeEntry::static_cell_count();
 225   }
 226   int header_cell = 0;
 227   if (args_cell + ret_cell > 0) {
 228     header_cell = header_cell_count();
 229   }
 230 
 231   return header_cell + args_cell + ret_cell;
 232 }
 233 
 234 class ArgumentOffsetComputer : public SignatureIterator {
 235 private:
 236   int _max;
 237   int _offset;
 238   GrowableArray<int> _offsets;
 239 
 240   friend class SignatureIterator;  // so do_parameters_on can call do_type
 241   void do_type(BasicType type) {
 242     if (is_reference_type(type) && _offsets.length() < _max) {
 243       _offsets.push(_offset);
 244     }
 245     _offset += parameter_type_word_count(type);
 246   }
 247 
 248  public:
 249   ArgumentOffsetComputer(Symbol* signature, int max)
 250     : SignatureIterator(signature),
 251       _max(max), _offset(0),
 252       _offsets(max) {
 253     do_parameters_on(this);  // non-virtual template execution
 254   }
 255 
 256   int off_at(int i) const { return _offsets.at(i); }
 257 };
 258 
 259 void TypeStackSlotEntries::post_initialize(Symbol* signature, bool has_receiver, bool include_receiver) {
 260   ResourceMark rm;
 261   int start = 0;
 262   // Parameter profiling include the receiver
 263   if (include_receiver && has_receiver) {
 264     set_stack_slot(0, 0);
 265     set_type(0, type_none());
 266     start += 1;
 267   }
 268   ArgumentOffsetComputer aos(signature, _number_of_entries-start);
 269   for (int i = start; i < _number_of_entries; i++) {
 270     set_stack_slot(i, aos.off_at(i-start) + (has_receiver ? 1 : 0));
 271     set_type(i, type_none());
 272   }
 273 }
 274 
 275 void CallTypeData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 276   assert(Bytecodes::is_invoke(stream->code()), "should be invoke");
 277   Bytecode_invoke inv(stream->method(), stream->bci());
 278 
 279   if (has_arguments()) {
 280 #ifdef ASSERT
 281     ResourceMark rm;
 282     ReferenceArgumentCount rac(inv.signature());
 283     int count = MIN2(rac.count(), (int)TypeProfileArgsLimit);
 284     assert(count > 0, "room for args type but none found?");
 285     check_number_of_arguments(count);
 286 #endif
 287     _args.post_initialize(inv.signature(), inv.has_receiver(), false);
 288   }
 289 
 290   if (has_return()) {
 291     assert(is_reference_type(inv.result_type()), "room for a ret type but doesn't return obj?");
 292     _ret.post_initialize();
 293   }
 294 }
 295 
 296 void VirtualCallTypeData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 297   assert(Bytecodes::is_invoke(stream->code()), "should be invoke");
 298   Bytecode_invoke inv(stream->method(), stream->bci());
 299 
 300   if (has_arguments()) {
 301 #ifdef ASSERT
 302     ResourceMark rm;
 303     ReferenceArgumentCount rac(inv.signature());
 304     int count = MIN2(rac.count(), (int)TypeProfileArgsLimit);
 305     assert(count > 0, "room for args type but none found?");
 306     check_number_of_arguments(count);
 307 #endif
 308     _args.post_initialize(inv.signature(), inv.has_receiver(), false);
 309   }
 310 
 311   if (has_return()) {
 312     assert(is_reference_type(inv.result_type()), "room for a ret type but doesn't return obj?");
 313     _ret.post_initialize();
 314   }
 315 }
 316 
 317 void TypeStackSlotEntries::clean_weak_klass_links(bool always_clean) {
 318   for (int i = 0; i < _number_of_entries; i++) {
 319     intptr_t p = type(i);
 320     Klass* k = (Klass*)klass_part(p);
 321     if (k != nullptr && (always_clean || !k->is_loader_alive())) {
 322       set_type(i, with_status((Klass*)nullptr, p));
 323     }
 324   }
 325 }
 326 
 327 void ReturnTypeEntry::clean_weak_klass_links(bool always_clean) {
 328   intptr_t p = type();
 329   Klass* k = (Klass*)klass_part(p);
 330   if (k != nullptr && (always_clean || !k->is_loader_alive())) {
 331     set_type(with_status((Klass*)nullptr, p));
 332   }
 333 }
 334 
 335 bool TypeEntriesAtCall::return_profiling_enabled() {
 336   return MethodData::profile_return();
 337 }
 338 
 339 bool TypeEntriesAtCall::arguments_profiling_enabled() {
 340   return MethodData::profile_arguments();
 341 }
 342 
 343 void TypeEntries::print_klass(outputStream* st, intptr_t k) {
 344   if (is_type_none(k)) {
 345     st->print("none");
 346   } else if (is_type_unknown(k)) {
 347     st->print("unknown");
 348   } else {
 349     valid_klass(k)->print_value_on(st);
 350   }
 351   if (was_null_seen(k)) {
 352     st->print(" (null seen)");
 353   }
 354 }
 355 
 356 void TypeStackSlotEntries::print_data_on(outputStream* st) const {
 357   for (int i = 0; i < _number_of_entries; i++) {
 358     _pd->tab(st);
 359     st->print("%d: stack(%u) ", i, stack_slot(i));
 360     print_klass(st, type(i));
 361     st->cr();
 362   }
 363 }
 364 
 365 void ReturnTypeEntry::print_data_on(outputStream* st) const {
 366   _pd->tab(st);
 367   print_klass(st, type());
 368   st->cr();
 369 }
 370 
 371 void CallTypeData::print_data_on(outputStream* st, const char* extra) const {
 372   CounterData::print_data_on(st, extra);
 373   if (has_arguments()) {
 374     tab(st, true);
 375     st->print("argument types");
 376     _args.print_data_on(st);
 377   }
 378   if (has_return()) {
 379     tab(st, true);
 380     st->print("return type");
 381     _ret.print_data_on(st);
 382   }
 383 }
 384 
 385 void VirtualCallTypeData::print_data_on(outputStream* st, const char* extra) const {
 386   VirtualCallData::print_data_on(st, extra);
 387   if (has_arguments()) {
 388     tab(st, true);
 389     st->print("argument types");
 390     _args.print_data_on(st);
 391   }
 392   if (has_return()) {
 393     tab(st, true);
 394     st->print("return type");
 395     _ret.print_data_on(st);
 396   }
 397 }
 398 
 399 // ==================================================================
 400 // ReceiverTypeData
 401 //
 402 // A ReceiverTypeData is used to access profiling information about a
 403 // dynamic type check.  It consists of a counter which counts the total times
 404 // that the check is reached, and a series of (Klass*, count) pairs
 405 // which are used to store a type profile for the receiver of the check.
 406 
 407 void ReceiverTypeData::clean_weak_klass_links(bool always_clean) {
 408     for (uint row = 0; row < row_limit(); row++) {
 409     Klass* p = receiver(row);
 410     if (p != nullptr && (always_clean || !p->is_loader_alive())) {
 411       clear_row(row);
 412     }
 413   }
 414 }
 415 
 416 void ReceiverTypeData::print_receiver_data_on(outputStream* st) const {
 417   uint row;
 418   int entries = 0;
 419   for (row = 0; row < row_limit(); row++) {
 420     if (receiver(row) != nullptr)  entries++;
 421   }
 422   st->print_cr("count(%u) entries(%u)", count(), entries);
 423   int total = count();
 424   for (row = 0; row < row_limit(); row++) {
 425     if (receiver(row) != nullptr) {
 426       total += receiver_count(row);
 427     }
 428   }
 429   for (row = 0; row < row_limit(); row++) {
 430     if (receiver(row) != nullptr) {
 431       tab(st);
 432       receiver(row)->print_value_on(st);
 433       st->print_cr("(%u %4.2f)", receiver_count(row), (float) receiver_count(row) / (float) total);
 434     }
 435   }
 436 }
 437 void ReceiverTypeData::print_data_on(outputStream* st, const char* extra) const {
 438   print_shared(st, "ReceiverTypeData", extra);
 439   print_receiver_data_on(st);
 440 }
 441 
 442 void VirtualCallData::print_data_on(outputStream* st, const char* extra) const {
 443   print_shared(st, "VirtualCallData", extra);
 444   print_receiver_data_on(st);
 445 }
 446 
 447 // ==================================================================
 448 // RetData
 449 //
 450 // A RetData is used to access profiling information for a ret bytecode.
 451 // It is composed of a count of the number of times that the ret has
 452 // been executed, followed by a series of triples of the form
 453 // (bci, count, di) which count the number of times that some bci was the
 454 // target of the ret and cache a corresponding displacement.
 455 
 456 void RetData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 457   for (uint row = 0; row < row_limit(); row++) {
 458     set_bci_displacement(row, -1);
 459     set_bci(row, no_bci);
 460   }
 461   // release so other threads see a consistent state.  bci is used as
 462   // a valid flag for bci_displacement.
 463   OrderAccess::release();
 464 }
 465 
 466 // This routine needs to atomically update the RetData structure, so the
 467 // caller needs to hold the RetData_lock before it gets here.  Since taking
 468 // the lock can block (and allow GC) and since RetData is a ProfileData is a
 469 // wrapper around a derived oop, taking the lock in _this_ method will
 470 // basically cause the 'this' pointer's _data field to contain junk after the
 471 // lock.  We require the caller to take the lock before making the ProfileData
 472 // structure.  Currently the only caller is InterpreterRuntime::update_mdp_for_ret
 473 address RetData::fixup_ret(int return_bci, MethodData* h_mdo) {
 474   // First find the mdp which corresponds to the return bci.
 475   address mdp = h_mdo->bci_to_dp(return_bci);
 476 
 477   // Now check to see if any of the cache slots are open.
 478   for (uint row = 0; row < row_limit(); row++) {
 479     if (bci(row) == no_bci) {
 480       set_bci_displacement(row, checked_cast<int>(mdp - dp()));
 481       set_bci_count(row, DataLayout::counter_increment);
 482       // Barrier to ensure displacement is written before the bci; allows
 483       // the interpreter to read displacement without fear of race condition.
 484       release_set_bci(row, return_bci);
 485       break;
 486     }
 487   }
 488   return mdp;
 489 }
 490 
 491 void RetData::print_data_on(outputStream* st, const char* extra) const {
 492   print_shared(st, "RetData", extra);
 493   uint row;
 494   int entries = 0;
 495   for (row = 0; row < row_limit(); row++) {
 496     if (bci(row) != no_bci)  entries++;
 497   }
 498   st->print_cr("count(%u) entries(%u)", count(), entries);
 499   for (row = 0; row < row_limit(); row++) {
 500     if (bci(row) != no_bci) {
 501       tab(st);
 502       st->print_cr("bci(%d: count(%u) displacement(%d))",
 503                    bci(row), bci_count(row), bci_displacement(row));
 504     }
 505   }
 506 }
 507 
 508 // ==================================================================
 509 // BranchData
 510 //
 511 // A BranchData is used to access profiling data for a two-way branch.
 512 // It consists of taken and not_taken counts as well as a data displacement
 513 // for the taken case.
 514 
 515 void BranchData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 516   assert(stream->bci() == bci(), "wrong pos");
 517   int target = stream->dest();
 518   int my_di = mdo->dp_to_di(dp());
 519   int target_di = mdo->bci_to_di(target);
 520   int offset = target_di - my_di;
 521   set_displacement(offset);
 522 }
 523 
 524 void BranchData::print_data_on(outputStream* st, const char* extra) const {
 525   print_shared(st, "BranchData", extra);
 526   st->print_cr("taken(%u) displacement(%d)",
 527                taken(), displacement());
 528   tab(st);
 529   st->print_cr("not taken(%u)", not_taken());
 530 }
 531 
 532 // ==================================================================
 533 // MultiBranchData
 534 //
 535 // A MultiBranchData is used to access profiling information for
 536 // a multi-way branch (*switch bytecodes).  It consists of a series
 537 // of (count, displacement) pairs, which count the number of times each
 538 // case was taken and specify the data displacement for each branch target.
 539 
 540 int MultiBranchData::compute_cell_count(BytecodeStream* stream) {
 541   int cell_count = 0;
 542   if (stream->code() == Bytecodes::_tableswitch) {
 543     Bytecode_tableswitch sw(stream->method()(), stream->bcp());
 544     cell_count = 1 + per_case_cell_count * (1 + sw.length()); // 1 for default
 545   } else {
 546     Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
 547     cell_count = 1 + per_case_cell_count * (sw.number_of_pairs() + 1); // 1 for default
 548   }
 549   return cell_count;
 550 }
 551 
 552 void MultiBranchData::post_initialize(BytecodeStream* stream,
 553                                       MethodData* mdo) {
 554   assert(stream->bci() == bci(), "wrong pos");
 555   int target;
 556   int my_di;
 557   int target_di;
 558   int offset;
 559   if (stream->code() == Bytecodes::_tableswitch) {
 560     Bytecode_tableswitch sw(stream->method()(), stream->bcp());
 561     int len = sw.length();
 562     assert(array_len() == per_case_cell_count * (len + 1), "wrong len");
 563     for (int count = 0; count < len; count++) {
 564       target = sw.dest_offset_at(count) + bci();
 565       my_di = mdo->dp_to_di(dp());
 566       target_di = mdo->bci_to_di(target);
 567       offset = target_di - my_di;
 568       set_displacement_at(count, offset);
 569     }
 570     target = sw.default_offset() + bci();
 571     my_di = mdo->dp_to_di(dp());
 572     target_di = mdo->bci_to_di(target);
 573     offset = target_di - my_di;
 574     set_default_displacement(offset);
 575 
 576   } else {
 577     Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
 578     int npairs = sw.number_of_pairs();
 579     assert(array_len() == per_case_cell_count * (npairs + 1), "wrong len");
 580     for (int count = 0; count < npairs; count++) {
 581       LookupswitchPair pair = sw.pair_at(count);
 582       target = pair.offset() + bci();
 583       my_di = mdo->dp_to_di(dp());
 584       target_di = mdo->bci_to_di(target);
 585       offset = target_di - my_di;
 586       set_displacement_at(count, offset);
 587     }
 588     target = sw.default_offset() + bci();
 589     my_di = mdo->dp_to_di(dp());
 590     target_di = mdo->bci_to_di(target);
 591     offset = target_di - my_di;
 592     set_default_displacement(offset);
 593   }
 594 }
 595 
 596 void MultiBranchData::print_data_on(outputStream* st, const char* extra) const {
 597   print_shared(st, "MultiBranchData", extra);
 598   st->print_cr("default_count(%u) displacement(%d)",
 599                default_count(), default_displacement());
 600   int cases = number_of_cases();
 601   for (int i = 0; i < cases; i++) {
 602     tab(st);
 603     st->print_cr("count(%u) displacement(%d)",
 604                  count_at(i), displacement_at(i));
 605   }
 606 }
 607 
 608 void ArgInfoData::print_data_on(outputStream* st, const char* extra) const {
 609   print_shared(st, "ArgInfoData", extra);
 610   int nargs = number_of_args();
 611   for (int i = 0; i < nargs; i++) {
 612     st->print("  0x%x", arg_modified(i));
 613   }
 614   st->cr();
 615 }
 616 
 617 int ParametersTypeData::compute_cell_count(Method* m) {
 618   if (!MethodData::profile_parameters_for_method(methodHandle(Thread::current(), m))) {
 619     return 0;
 620   }
 621   int max = TypeProfileParmsLimit == -1 ? INT_MAX : TypeProfileParmsLimit;
 622   int obj_args = TypeStackSlotEntries::compute_cell_count(m->signature(), !m->is_static(), max);
 623   if (obj_args > 0) {
 624     return obj_args + 1; // 1 cell for array len
 625   }
 626   return 0;
 627 }
 628 
 629 void ParametersTypeData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 630   _parameters.post_initialize(mdo->method()->signature(), !mdo->method()->is_static(), true);
 631 }
 632 
 633 bool ParametersTypeData::profiling_enabled() {
 634   return MethodData::profile_parameters();
 635 }
 636 
 637 void ParametersTypeData::print_data_on(outputStream* st, const char* extra) const {
 638   print_shared(st, "ParametersTypeData", extra);
 639   tab(st);
 640   _parameters.print_data_on(st);
 641   st->cr();
 642 }
 643 
 644 void SpeculativeTrapData::print_data_on(outputStream* st, const char* extra) const {
 645   print_shared(st, "SpeculativeTrapData", extra);
 646   tab(st);
 647   method()->print_short_name(st);
 648   st->cr();
 649 }
 650 
 651 // ==================================================================
 652 // MethodData*
 653 //
 654 // A MethodData* holds information which has been collected about
 655 // a method.
 656 
 657 MethodData* MethodData::allocate(ClassLoaderData* loader_data, const methodHandle& method, TRAPS) {
 658   assert(!THREAD->owns_locks(), "Should not own any locks");
 659   int size = MethodData::compute_allocation_size_in_words(method);
 660 
 661   return new (loader_data, size, MetaspaceObj::MethodDataType, THREAD)
 662     MethodData(method);
 663 }
 664 
 665 int MethodData::bytecode_cell_count(Bytecodes::Code code) {
 666   switch (code) {
 667   case Bytecodes::_checkcast:
 668   case Bytecodes::_instanceof:
 669   case Bytecodes::_aastore:
 670     if (TypeProfileCasts) {
 671       return ReceiverTypeData::static_cell_count();
 672     } else {
 673       return BitData::static_cell_count();
 674     }
 675   case Bytecodes::_invokespecial:
 676   case Bytecodes::_invokestatic:
 677     if (MethodData::profile_arguments() || MethodData::profile_return()) {
 678       return variable_cell_count;
 679     } else {
 680       return CounterData::static_cell_count();
 681     }
 682   case Bytecodes::_goto:
 683   case Bytecodes::_goto_w:
 684   case Bytecodes::_jsr:
 685   case Bytecodes::_jsr_w:
 686     return JumpData::static_cell_count();
 687   case Bytecodes::_invokevirtual:
 688   case Bytecodes::_invokeinterface:
 689     if (MethodData::profile_arguments() || MethodData::profile_return()) {
 690       return variable_cell_count;
 691     } else {
 692       return VirtualCallData::static_cell_count();
 693     }
 694   case Bytecodes::_invokedynamic:
 695     if (MethodData::profile_arguments() || MethodData::profile_return()) {
 696       return variable_cell_count;
 697     } else {
 698       return CounterData::static_cell_count();
 699     }
 700   case Bytecodes::_ret:
 701     return RetData::static_cell_count();
 702   case Bytecodes::_ifeq:
 703   case Bytecodes::_ifne:
 704   case Bytecodes::_iflt:
 705   case Bytecodes::_ifge:
 706   case Bytecodes::_ifgt:
 707   case Bytecodes::_ifle:
 708   case Bytecodes::_if_icmpeq:
 709   case Bytecodes::_if_icmpne:
 710   case Bytecodes::_if_icmplt:
 711   case Bytecodes::_if_icmpge:
 712   case Bytecodes::_if_icmpgt:
 713   case Bytecodes::_if_icmple:
 714   case Bytecodes::_if_acmpeq:
 715   case Bytecodes::_if_acmpne:
 716   case Bytecodes::_ifnull:
 717   case Bytecodes::_ifnonnull:
 718     return BranchData::static_cell_count();
 719   case Bytecodes::_lookupswitch:
 720   case Bytecodes::_tableswitch:
 721     return variable_cell_count;
 722   default:
 723     return no_profile_data;
 724   }
 725 }
 726 
 727 // Compute the size of the profiling information corresponding to
 728 // the current bytecode.
 729 int MethodData::compute_data_size(BytecodeStream* stream) {
 730   int cell_count = bytecode_cell_count(stream->code());
 731   if (cell_count == no_profile_data) {
 732     return 0;
 733   }
 734   if (cell_count == variable_cell_count) {
 735     switch (stream->code()) {
 736     case Bytecodes::_lookupswitch:
 737     case Bytecodes::_tableswitch:
 738       cell_count = MultiBranchData::compute_cell_count(stream);
 739       break;
 740     case Bytecodes::_invokespecial:
 741     case Bytecodes::_invokestatic:
 742     case Bytecodes::_invokedynamic:
 743       assert(MethodData::profile_arguments() || MethodData::profile_return(), "should be collecting args profile");
 744       if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 745           profile_return_for_invoke(stream->method(), stream->bci())) {
 746         cell_count = CallTypeData::compute_cell_count(stream);
 747       } else {
 748         cell_count = CounterData::static_cell_count();
 749       }
 750       break;
 751     case Bytecodes::_invokevirtual:
 752     case Bytecodes::_invokeinterface: {
 753       assert(MethodData::profile_arguments() || MethodData::profile_return(), "should be collecting args profile");
 754       if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 755           profile_return_for_invoke(stream->method(), stream->bci())) {
 756         cell_count = VirtualCallTypeData::compute_cell_count(stream);
 757       } else {
 758         cell_count = VirtualCallData::static_cell_count();
 759       }
 760       break;
 761     }
 762     default:
 763       fatal("unexpected bytecode for var length profile data");
 764     }
 765   }
 766   // Note:  cell_count might be zero, meaning that there is just
 767   //        a DataLayout header, with no extra cells.
 768   assert(cell_count >= 0, "sanity");
 769   return DataLayout::compute_size_in_bytes(cell_count);
 770 }
 771 
 772 bool MethodData::is_speculative_trap_bytecode(Bytecodes::Code code) {
 773   // Bytecodes for which we may use speculation
 774   switch (code) {
 775   case Bytecodes::_checkcast:
 776   case Bytecodes::_instanceof:
 777   case Bytecodes::_aastore:
 778   case Bytecodes::_invokevirtual:
 779   case Bytecodes::_invokeinterface:
 780   case Bytecodes::_if_acmpeq:
 781   case Bytecodes::_if_acmpne:
 782   case Bytecodes::_ifnull:
 783   case Bytecodes::_ifnonnull:
 784   case Bytecodes::_invokestatic:
 785 #ifdef COMPILER2
 786     if (CompilerConfig::is_c2_enabled()) {
 787       return UseTypeSpeculation;
 788     }
 789 #endif
 790   default:
 791     return false;
 792   }
 793   return false;
 794 }
 795 
 796 #if INCLUDE_JVMCI
 797 
 798 void* FailedSpeculation::operator new(size_t size, size_t fs_size) throw() {
 799   return CHeapObj<mtCompiler>::operator new(fs_size, std::nothrow);
 800 }
 801 
 802 FailedSpeculation::FailedSpeculation(address speculation, int speculation_len) : _data_len(speculation_len), _next(nullptr) {
 803   memcpy(data(), speculation, speculation_len);
 804 }
 805 
 806 // A heuristic check to detect nmethods that outlive a failed speculations list.
 807 static void guarantee_failed_speculations_alive(nmethod* nm, FailedSpeculation** failed_speculations_address) {
 808   jlong head = (jlong)(address) *failed_speculations_address;
 809   if ((head & 0x1) == 0x1) {
 810     stringStream st;
 811     if (nm != nullptr) {
 812       st.print("%d", nm->compile_id());
 813       Method* method = nm->method();
 814       st.print_raw("{");
 815       if (method != nullptr) {
 816         method->print_name(&st);
 817       } else {
 818         const char* jvmci_name = nm->jvmci_name();
 819         if (jvmci_name != nullptr) {
 820           st.print_raw(jvmci_name);
 821         }
 822       }
 823       st.print_raw("}");
 824     } else {
 825       st.print("<unknown>");
 826     }
 827     fatal("Adding to failed speculations list that appears to have been freed. Source: %s", st.as_string());
 828   }
 829 }
 830 
 831 bool FailedSpeculation::add_failed_speculation(nmethod* nm, FailedSpeculation** failed_speculations_address, address speculation, int speculation_len) {
 832   assert(failed_speculations_address != nullptr, "must be");
 833   size_t fs_size = sizeof(FailedSpeculation) + speculation_len;
 834 
 835   guarantee_failed_speculations_alive(nm, failed_speculations_address);
 836 
 837   FailedSpeculation** cursor = failed_speculations_address;
 838   FailedSpeculation* fs = nullptr;
 839   do {
 840     if (*cursor == nullptr) {
 841       if (fs == nullptr) {
 842         // lazily allocate FailedSpeculation
 843         fs = new (fs_size) FailedSpeculation(speculation, speculation_len);
 844         if (fs == nullptr) {
 845           // no memory -> ignore failed speculation
 846           return false;
 847         }
 848         guarantee(is_aligned(fs, sizeof(FailedSpeculation*)), "FailedSpeculation objects must be pointer aligned");
 849       }
 850       FailedSpeculation* old_fs = Atomic::cmpxchg(cursor, (FailedSpeculation*) nullptr, fs);
 851       if (old_fs == nullptr) {
 852         // Successfully appended fs to end of the list
 853         return true;
 854       }
 855     }
 856     guarantee(*cursor != nullptr, "cursor must point to non-null FailedSpeculation");
 857     // check if the current entry matches this thread's failed speculation
 858     if ((*cursor)->data_len() == speculation_len && memcmp(speculation, (*cursor)->data(), speculation_len) == 0) {
 859       if (fs != nullptr) {
 860         delete fs;
 861       }
 862       return false;
 863     }
 864     cursor = (*cursor)->next_adr();
 865   } while (true);
 866 }
 867 
 868 void FailedSpeculation::free_failed_speculations(FailedSpeculation** failed_speculations_address) {
 869   assert(failed_speculations_address != nullptr, "must be");
 870   FailedSpeculation* fs = *failed_speculations_address;
 871   while (fs != nullptr) {
 872     FailedSpeculation* next = fs->next();
 873     delete fs;
 874     fs = next;
 875   }
 876 
 877   // Write an unaligned value to failed_speculations_address to denote
 878   // that it is no longer a valid pointer. This is allows for the check
 879   // in add_failed_speculation against adding to a freed failed
 880   // speculations list.
 881   long* head = (long*) failed_speculations_address;
 882   (*head) = (*head) | 0x1;
 883 }
 884 #endif // INCLUDE_JVMCI
 885 
 886 int MethodData::compute_extra_data_count(int data_size, int empty_bc_count, bool needs_speculative_traps) {
 887 #if INCLUDE_JVMCI
 888   if (ProfileTraps) {
 889     // Assume that up to 30% of the possibly trapping BCIs with no MDP will need to allocate one.
 890     int extra_data_count = MIN2(empty_bc_count, MAX2(4, (empty_bc_count * 30) / 100));
 891 
 892     // Make sure we have a minimum number of extra data slots to
 893     // allocate SpeculativeTrapData entries. We would want to have one
 894     // entry per compilation that inlines this method and for which
 895     // some type speculation assumption fails. So the room we need for
 896     // the SpeculativeTrapData entries doesn't directly depend on the
 897     // size of the method. Because it's hard to estimate, we reserve
 898     // space for an arbitrary number of entries.
 899     int spec_data_count = (needs_speculative_traps ? SpecTrapLimitExtraEntries : 0) *
 900       (SpeculativeTrapData::static_cell_count() + DataLayout::header_size_in_cells());
 901 
 902     return MAX2(extra_data_count, spec_data_count);
 903   } else {
 904     return 0;
 905   }
 906 #else // INCLUDE_JVMCI
 907   if (ProfileTraps) {
 908     // Assume that up to 3% of BCIs with no MDP will need to allocate one.
 909     int extra_data_count = (uint)(empty_bc_count * 3) / 128 + 1;
 910     // If the method is large, let the extra BCIs grow numerous (to ~1%).
 911     int one_percent_of_data
 912       = (uint)data_size / (DataLayout::header_size_in_bytes()*128);
 913     if (extra_data_count < one_percent_of_data)
 914       extra_data_count = one_percent_of_data;
 915     if (extra_data_count > empty_bc_count)
 916       extra_data_count = empty_bc_count;  // no need for more
 917 
 918     // Make sure we have a minimum number of extra data slots to
 919     // allocate SpeculativeTrapData entries. We would want to have one
 920     // entry per compilation that inlines this method and for which
 921     // some type speculation assumption fails. So the room we need for
 922     // the SpeculativeTrapData entries doesn't directly depend on the
 923     // size of the method. Because it's hard to estimate, we reserve
 924     // space for an arbitrary number of entries.
 925     int spec_data_count = (needs_speculative_traps ? SpecTrapLimitExtraEntries : 0) *
 926       (SpeculativeTrapData::static_cell_count() + DataLayout::header_size_in_cells());
 927 
 928     return MAX2(extra_data_count, spec_data_count);
 929   } else {
 930     return 0;
 931   }
 932 #endif // INCLUDE_JVMCI
 933 }
 934 
 935 // Compute the size of the MethodData* necessary to store
 936 // profiling information about a given method.  Size is in bytes.
 937 int MethodData::compute_allocation_size_in_bytes(const methodHandle& method) {
 938   int data_size = 0;
 939   BytecodeStream stream(method);
 940   Bytecodes::Code c;
 941   int empty_bc_count = 0;  // number of bytecodes lacking data
 942   bool needs_speculative_traps = false;
 943   while ((c = stream.next()) >= 0) {
 944     int size_in_bytes = compute_data_size(&stream);
 945     data_size += size_in_bytes;
 946     if (size_in_bytes == 0 JVMCI_ONLY(&& Bytecodes::can_trap(c)))  empty_bc_count += 1;
 947     needs_speculative_traps = needs_speculative_traps || is_speculative_trap_bytecode(c);
 948   }
 949   int object_size = in_bytes(data_offset()) + data_size;
 950 
 951   // Add some extra DataLayout cells (at least one) to track stray traps.
 952   int extra_data_count = compute_extra_data_count(data_size, empty_bc_count, needs_speculative_traps);
 953   object_size += extra_data_count * DataLayout::compute_size_in_bytes(0);
 954 
 955   // Add a cell to record information about modified arguments.
 956   int arg_size = method->size_of_parameters();
 957   object_size += DataLayout::compute_size_in_bytes(arg_size+1);
 958 
 959   // Reserve room for an area of the MDO dedicated to profiling of
 960   // parameters
 961   int args_cell = ParametersTypeData::compute_cell_count(method());
 962   if (args_cell > 0) {
 963     object_size += DataLayout::compute_size_in_bytes(args_cell);
 964   }
 965 
 966   if (ProfileExceptionHandlers && method()->has_exception_handler()) {
 967     int num_exception_handlers = method()->exception_table_length();
 968     object_size += num_exception_handlers * single_exception_handler_data_size();
 969   }
 970 
 971   return object_size;
 972 }
 973 
 974 // Compute the size of the MethodData* necessary to store
 975 // profiling information about a given method.  Size is in words
 976 int MethodData::compute_allocation_size_in_words(const methodHandle& method) {
 977   int byte_size = compute_allocation_size_in_bytes(method);
 978   int word_size = align_up(byte_size, BytesPerWord) / BytesPerWord;
 979   return align_metadata_size(word_size);
 980 }
 981 
 982 // Initialize an individual data segment.  Returns the size of
 983 // the segment in bytes.
 984 int MethodData::initialize_data(BytecodeStream* stream,
 985                                        int data_index) {
 986   int cell_count = -1;
 987   u1 tag = DataLayout::no_tag;
 988   DataLayout* data_layout = data_layout_at(data_index);
 989   Bytecodes::Code c = stream->code();
 990   switch (c) {
 991   case Bytecodes::_checkcast:
 992   case Bytecodes::_instanceof:
 993   case Bytecodes::_aastore:
 994     if (TypeProfileCasts) {
 995       cell_count = ReceiverTypeData::static_cell_count();
 996       tag = DataLayout::receiver_type_data_tag;
 997     } else {
 998       cell_count = BitData::static_cell_count();
 999       tag = DataLayout::bit_data_tag;
1000     }
1001     break;
1002   case Bytecodes::_invokespecial:
1003   case Bytecodes::_invokestatic: {
1004     int counter_data_cell_count = CounterData::static_cell_count();
1005     if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
1006         profile_return_for_invoke(stream->method(), stream->bci())) {
1007       cell_count = CallTypeData::compute_cell_count(stream);
1008     } else {
1009       cell_count = counter_data_cell_count;
1010     }
1011     if (cell_count > counter_data_cell_count) {
1012       tag = DataLayout::call_type_data_tag;
1013     } else {
1014       tag = DataLayout::counter_data_tag;
1015     }
1016     break;
1017   }
1018   case Bytecodes::_goto:
1019   case Bytecodes::_goto_w:
1020   case Bytecodes::_jsr:
1021   case Bytecodes::_jsr_w:
1022     cell_count = JumpData::static_cell_count();
1023     tag = DataLayout::jump_data_tag;
1024     break;
1025   case Bytecodes::_invokevirtual:
1026   case Bytecodes::_invokeinterface: {
1027     int virtual_call_data_cell_count = VirtualCallData::static_cell_count();
1028     if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
1029         profile_return_for_invoke(stream->method(), stream->bci())) {
1030       cell_count = VirtualCallTypeData::compute_cell_count(stream);
1031     } else {
1032       cell_count = virtual_call_data_cell_count;
1033     }
1034     if (cell_count > virtual_call_data_cell_count) {
1035       tag = DataLayout::virtual_call_type_data_tag;
1036     } else {
1037       tag = DataLayout::virtual_call_data_tag;
1038     }
1039     break;
1040   }
1041   case Bytecodes::_invokedynamic: {
1042     // %%% should make a type profile for any invokedynamic that takes a ref argument
1043     int counter_data_cell_count = CounterData::static_cell_count();
1044     if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
1045         profile_return_for_invoke(stream->method(), stream->bci())) {
1046       cell_count = CallTypeData::compute_cell_count(stream);
1047     } else {
1048       cell_count = counter_data_cell_count;
1049     }
1050     if (cell_count > counter_data_cell_count) {
1051       tag = DataLayout::call_type_data_tag;
1052     } else {
1053       tag = DataLayout::counter_data_tag;
1054     }
1055     break;
1056   }
1057   case Bytecodes::_ret:
1058     cell_count = RetData::static_cell_count();
1059     tag = DataLayout::ret_data_tag;
1060     break;
1061   case Bytecodes::_ifeq:
1062   case Bytecodes::_ifne:
1063   case Bytecodes::_iflt:
1064   case Bytecodes::_ifge:
1065   case Bytecodes::_ifgt:
1066   case Bytecodes::_ifle:
1067   case Bytecodes::_if_icmpeq:
1068   case Bytecodes::_if_icmpne:
1069   case Bytecodes::_if_icmplt:
1070   case Bytecodes::_if_icmpge:
1071   case Bytecodes::_if_icmpgt:
1072   case Bytecodes::_if_icmple:
1073   case Bytecodes::_if_acmpeq:
1074   case Bytecodes::_if_acmpne:
1075   case Bytecodes::_ifnull:
1076   case Bytecodes::_ifnonnull:
1077     cell_count = BranchData::static_cell_count();
1078     tag = DataLayout::branch_data_tag;
1079     break;
1080   case Bytecodes::_lookupswitch:
1081   case Bytecodes::_tableswitch:
1082     cell_count = MultiBranchData::compute_cell_count(stream);
1083     tag = DataLayout::multi_branch_data_tag;
1084     break;
1085   default:
1086     break;
1087   }
1088   assert(tag == DataLayout::multi_branch_data_tag ||
1089          ((MethodData::profile_arguments() || MethodData::profile_return()) &&
1090           (tag == DataLayout::call_type_data_tag ||
1091            tag == DataLayout::counter_data_tag ||
1092            tag == DataLayout::virtual_call_type_data_tag ||
1093            tag == DataLayout::virtual_call_data_tag)) ||
1094          cell_count == bytecode_cell_count(c), "cell counts must agree");
1095   if (cell_count >= 0) {
1096     assert(tag != DataLayout::no_tag, "bad tag");
1097     assert(bytecode_has_profile(c), "agree w/ BHP");
1098     data_layout->initialize(tag, checked_cast<u2>(stream->bci()), cell_count);
1099     return DataLayout::compute_size_in_bytes(cell_count);
1100   } else {
1101     assert(!bytecode_has_profile(c), "agree w/ !BHP");
1102     return 0;
1103   }
1104 }
1105 
1106 // Get the data at an arbitrary (sort of) data index.
1107 ProfileData* MethodData::data_at(int data_index) const {
1108   if (out_of_bounds(data_index)) {
1109     return nullptr;
1110   }
1111   DataLayout* data_layout = data_layout_at(data_index);
1112   return data_layout->data_in();
1113 }
1114 
1115 int DataLayout::cell_count() {
1116   switch (tag()) {
1117   case DataLayout::no_tag:
1118   default:
1119     ShouldNotReachHere();
1120     return 0;
1121   case DataLayout::bit_data_tag:
1122     return BitData::static_cell_count();
1123   case DataLayout::counter_data_tag:
1124     return CounterData::static_cell_count();
1125   case DataLayout::jump_data_tag:
1126     return JumpData::static_cell_count();
1127   case DataLayout::receiver_type_data_tag:
1128     return ReceiverTypeData::static_cell_count();
1129   case DataLayout::virtual_call_data_tag:
1130     return VirtualCallData::static_cell_count();
1131   case DataLayout::ret_data_tag:
1132     return RetData::static_cell_count();
1133   case DataLayout::branch_data_tag:
1134     return BranchData::static_cell_count();
1135   case DataLayout::multi_branch_data_tag:
1136     return ((new MultiBranchData(this))->cell_count());
1137   case DataLayout::arg_info_data_tag:
1138     return ((new ArgInfoData(this))->cell_count());
1139   case DataLayout::call_type_data_tag:
1140     return ((new CallTypeData(this))->cell_count());
1141   case DataLayout::virtual_call_type_data_tag:
1142     return ((new VirtualCallTypeData(this))->cell_count());
1143   case DataLayout::parameters_type_data_tag:
1144     return ((new ParametersTypeData(this))->cell_count());
1145   case DataLayout::speculative_trap_data_tag:
1146     return SpeculativeTrapData::static_cell_count();
1147   }
1148 }
1149 ProfileData* DataLayout::data_in() {
1150   switch (tag()) {
1151   case DataLayout::no_tag:
1152   default:
1153     ShouldNotReachHere();
1154     return nullptr;
1155   case DataLayout::bit_data_tag:
1156     return new BitData(this);
1157   case DataLayout::counter_data_tag:
1158     return new CounterData(this);
1159   case DataLayout::jump_data_tag:
1160     return new JumpData(this);
1161   case DataLayout::receiver_type_data_tag:
1162     return new ReceiverTypeData(this);
1163   case DataLayout::virtual_call_data_tag:
1164     return new VirtualCallData(this);
1165   case DataLayout::ret_data_tag:
1166     return new RetData(this);
1167   case DataLayout::branch_data_tag:
1168     return new BranchData(this);
1169   case DataLayout::multi_branch_data_tag:
1170     return new MultiBranchData(this);
1171   case DataLayout::arg_info_data_tag:
1172     return new ArgInfoData(this);
1173   case DataLayout::call_type_data_tag:
1174     return new CallTypeData(this);
1175   case DataLayout::virtual_call_type_data_tag:
1176     return new VirtualCallTypeData(this);
1177   case DataLayout::parameters_type_data_tag:
1178     return new ParametersTypeData(this);
1179   case DataLayout::speculative_trap_data_tag:
1180     return new SpeculativeTrapData(this);
1181   }
1182 }
1183 
1184 // Iteration over data.
1185 ProfileData* MethodData::next_data(ProfileData* current) const {
1186   int current_index = dp_to_di(current->dp());
1187   int next_index = current_index + current->size_in_bytes();
1188   ProfileData* next = data_at(next_index);
1189   return next;
1190 }
1191 
1192 DataLayout* MethodData::next_data_layout(DataLayout* current) const {
1193   int current_index = dp_to_di((address)current);
1194   int next_index = current_index + current->size_in_bytes();
1195   if (out_of_bounds(next_index)) {
1196     return nullptr;
1197   }
1198   DataLayout* next = data_layout_at(next_index);
1199   return next;
1200 }
1201 
1202 // Give each of the data entries a chance to perform specific
1203 // data initialization.
1204 void MethodData::post_initialize(BytecodeStream* stream) {
1205   ResourceMark rm;
1206   ProfileData* data;
1207   for (data = first_data(); is_valid(data); data = next_data(data)) {
1208     stream->set_start(data->bci());
1209     stream->next();
1210     data->post_initialize(stream, this);
1211   }
1212   if (_parameters_type_data_di != no_parameters) {
1213     parameters_type_data()->post_initialize(nullptr, this);
1214   }
1215 }
1216 
1217 // Initialize the MethodData* corresponding to a given method.
1218 MethodData::MethodData(const methodHandle& method)
1219   : _method(method()),
1220     // Holds Compile_lock
1221     _extra_data_lock(Mutex::nosafepoint, "MDOExtraData_lock"),
1222     _compiler_counters(),
1223     _parameters_type_data_di(parameters_uninitialized) {
1224   initialize();
1225 }
1226 
1227 void MethodData::initialize() {
1228   Thread* thread = Thread::current();
1229   NoSafepointVerifier no_safepoint;  // init function atomic wrt GC
1230   ResourceMark rm(thread);
1231 
1232   init();
1233   set_creation_mileage(mileage_of(method()));
1234 
1235   // Go through the bytecodes and allocate and initialize the
1236   // corresponding data cells.
1237   int data_size = 0;
1238   int empty_bc_count = 0;  // number of bytecodes lacking data
1239   _data[0] = 0;  // apparently not set below.
1240   BytecodeStream stream(methodHandle(thread, method()));
1241   Bytecodes::Code c;
1242   bool needs_speculative_traps = false;
1243   while ((c = stream.next()) >= 0) {
1244     int size_in_bytes = initialize_data(&stream, data_size);
1245     data_size += size_in_bytes;
1246     if (size_in_bytes == 0 JVMCI_ONLY(&& Bytecodes::can_trap(c)))  empty_bc_count += 1;
1247     needs_speculative_traps = needs_speculative_traps || is_speculative_trap_bytecode(c);
1248   }
1249   _data_size = data_size;
1250   int object_size = in_bytes(data_offset()) + data_size;
1251 
1252   // Add some extra DataLayout cells (at least one) to track stray traps.
1253   int extra_data_count = compute_extra_data_count(data_size, empty_bc_count, needs_speculative_traps);
1254   int extra_size = extra_data_count * DataLayout::compute_size_in_bytes(0);
1255 
1256   // Let's zero the space for the extra data
1257   if (extra_size > 0) {
1258     Copy::zero_to_bytes(((address)_data) + data_size, extra_size);
1259   }
1260 
1261   // Add a cell to record information about modified arguments.
1262   // Set up _args_modified array after traps cells so that
1263   // the code for traps cells works.
1264   DataLayout *dp = data_layout_at(data_size + extra_size);
1265 
1266   int arg_size = method()->size_of_parameters();
1267   dp->initialize(DataLayout::arg_info_data_tag, 0, arg_size+1);
1268 
1269   int arg_data_size = DataLayout::compute_size_in_bytes(arg_size+1);
1270   object_size += extra_size + arg_data_size;
1271 
1272   int parms_cell = ParametersTypeData::compute_cell_count(method());
1273   // If we are profiling parameters, we reserved an area near the end
1274   // of the MDO after the slots for bytecodes (because there's no bci
1275   // for method entry so they don't fit with the framework for the
1276   // profiling of bytecodes). We store the offset within the MDO of
1277   // this area (or -1 if no parameter is profiled)
1278   int parm_data_size = 0;
1279   if (parms_cell > 0) {
1280     parm_data_size = DataLayout::compute_size_in_bytes(parms_cell);
1281     object_size += parm_data_size;
1282     _parameters_type_data_di = data_size + extra_size + arg_data_size;
1283     DataLayout *dp = data_layout_at(data_size + extra_size + arg_data_size);
1284     dp->initialize(DataLayout::parameters_type_data_tag, 0, parms_cell);
1285   } else {
1286     _parameters_type_data_di = no_parameters;
1287   }
1288 
1289   _exception_handler_data_di = data_size + extra_size + arg_data_size + parm_data_size;
1290   if (ProfileExceptionHandlers && method()->has_exception_handler()) {
1291     int num_exception_handlers = method()->exception_table_length();
1292     object_size += num_exception_handlers * single_exception_handler_data_size();
1293     ExceptionTableElement* exception_handlers = method()->exception_table_start();
1294     for (int i = 0; i < num_exception_handlers; i++) {
1295       DataLayout *dp = exception_handler_data_at(i);
1296       dp->initialize(DataLayout::bit_data_tag, exception_handlers[i].handler_pc, single_exception_handler_data_cell_count());
1297     }
1298   }
1299 
1300   // Set an initial hint. Don't use set_hint_di() because
1301   // first_di() may be out of bounds if data_size is 0.
1302   // In that situation, _hint_di is never used, but at
1303   // least well-defined.
1304   _hint_di = first_di();
1305 
1306   post_initialize(&stream);
1307 
1308   assert(object_size == compute_allocation_size_in_bytes(methodHandle(thread, _method)), "MethodData: computed size != initialized size");
1309   set_size(object_size);
1310 }
1311 
1312 void MethodData::init() {
1313   _compiler_counters = CompilerCounters(); // reset compiler counters
1314   _invocation_counter.init();
1315   _backedge_counter.init();
1316   _invocation_counter_start = 0;
1317   _backedge_counter_start = 0;
1318 
1319   // Set per-method invoke- and backedge mask.
1320   double scale = 1.0;
1321   methodHandle mh(Thread::current(), _method);
1322   CompilerOracle::has_option_value(mh, CompileCommandEnum::CompileThresholdScaling, scale);
1323   _invoke_mask = (int)right_n_bits(CompilerConfig::scaled_freq_log(Tier0InvokeNotifyFreqLog, scale)) << InvocationCounter::count_shift;
1324   _backedge_mask = (int)right_n_bits(CompilerConfig::scaled_freq_log(Tier0BackedgeNotifyFreqLog, scale)) << InvocationCounter::count_shift;
1325 
1326   _tenure_traps = 0;
1327   _num_loops = 0;
1328   _num_blocks = 0;
1329   _would_profile = unknown;
1330 
1331 #if INCLUDE_JVMCI
1332   _jvmci_ir_size = 0;
1333   _failed_speculations = nullptr;
1334 #endif
1335 
1336 #if INCLUDE_RTM_OPT
1337   _rtm_state = NoRTM; // No RTM lock eliding by default
1338   if (UseRTMLocking &&
1339       !CompilerOracle::has_option(mh, CompileCommandEnum::NoRTMLockEliding)) {
1340     if (CompilerOracle::has_option(mh, CompileCommandEnum::UseRTMLockEliding) || !UseRTMDeopt) {
1341       // Generate RTM lock eliding code without abort ratio calculation code.
1342       _rtm_state = UseRTM;
1343     } else if (UseRTMDeopt) {
1344       // Generate RTM lock eliding code and include abort ratio calculation
1345       // code if UseRTMDeopt is on.
1346       _rtm_state = ProfileRTM;
1347     }
1348   }
1349 #endif
1350 
1351   // Initialize escape flags.
1352   clear_escape_info();
1353 }
1354 
1355 // Get a measure of how much mileage the method has on it.
1356 int MethodData::mileage_of(Method* method) {
1357   return MAX2(method->invocation_count(), method->backedge_count());
1358 }
1359 
1360 bool MethodData::is_mature() const {
1361   return CompilationPolicy::is_mature(_method);
1362 }
1363 
1364 // Translate a bci to its corresponding data index (di).
1365 address MethodData::bci_to_dp(int bci) {
1366   ResourceMark rm;
1367   DataLayout* data = data_layout_before(bci);
1368   DataLayout* prev = nullptr;
1369   for ( ; is_valid(data); data = next_data_layout(data)) {
1370     if (data->bci() >= bci) {
1371       if (data->bci() == bci)  set_hint_di(dp_to_di((address)data));
1372       else if (prev != nullptr)   set_hint_di(dp_to_di((address)prev));
1373       return (address)data;
1374     }
1375     prev = data;
1376   }
1377   return (address)limit_data_position();
1378 }
1379 
1380 // Translate a bci to its corresponding data, or null.
1381 ProfileData* MethodData::bci_to_data(int bci) {
1382   check_extra_data_locked();
1383 
1384   DataLayout* data = data_layout_before(bci);
1385   for ( ; is_valid(data); data = next_data_layout(data)) {
1386     if (data->bci() == bci) {
1387       set_hint_di(dp_to_di((address)data));
1388       return data->data_in();
1389     } else if (data->bci() > bci) {
1390       break;
1391     }
1392   }
1393   return bci_to_extra_data(bci, nullptr, false);
1394 }
1395 
1396 DataLayout* MethodData::exception_handler_bci_to_data_helper(int bci) {
1397   assert(ProfileExceptionHandlers, "not profiling");
1398   for (int i = 0; i < num_exception_handler_data(); i++) {
1399     DataLayout* exception_handler_data = exception_handler_data_at(i);
1400     if (exception_handler_data->bci() == bci) {
1401       return exception_handler_data;
1402     }
1403   }
1404   return nullptr;
1405 }
1406 
1407 BitData* MethodData::exception_handler_bci_to_data_or_null(int bci) {
1408   DataLayout* data = exception_handler_bci_to_data_helper(bci);
1409   return data != nullptr ? new BitData(data) : nullptr;
1410 }
1411 
1412 BitData MethodData::exception_handler_bci_to_data(int bci) {
1413   DataLayout* data = exception_handler_bci_to_data_helper(bci);
1414   assert(data != nullptr, "invalid bci");
1415   return BitData(data);
1416 }
1417 
1418 DataLayout* MethodData::next_extra(DataLayout* dp) {
1419   int nb_cells = 0;
1420   switch(dp->tag()) {
1421   case DataLayout::bit_data_tag:
1422   case DataLayout::no_tag:
1423     nb_cells = BitData::static_cell_count();
1424     break;
1425   case DataLayout::speculative_trap_data_tag:
1426     nb_cells = SpeculativeTrapData::static_cell_count();
1427     break;
1428   default:
1429     fatal("unexpected tag %d", dp->tag());
1430   }
1431   return (DataLayout*)((address)dp + DataLayout::compute_size_in_bytes(nb_cells));
1432 }
1433 
1434 ProfileData* MethodData::bci_to_extra_data_find(int bci, Method* m, DataLayout*& dp) {
1435   check_extra_data_locked();
1436 
1437   DataLayout* end = args_data_limit();
1438 
1439   for (;; dp = next_extra(dp)) {
1440     assert(dp < end, "moved past end of extra data");
1441     // No need for "Atomic::load_acquire" ops,
1442     // since the data structure is monotonic.
1443     switch(dp->tag()) {
1444     case DataLayout::no_tag:
1445       return nullptr;
1446     case DataLayout::arg_info_data_tag:
1447       dp = end;
1448       return nullptr; // ArgInfoData is at the end of extra data section.
1449     case DataLayout::bit_data_tag:
1450       if (m == nullptr && dp->bci() == bci) {
1451         return new BitData(dp);
1452       }
1453       break;
1454     case DataLayout::speculative_trap_data_tag:
1455       if (m != nullptr) {
1456         SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1457         if (dp->bci() == bci) {
1458           assert(data->method() != nullptr, "method must be set");
1459           if (data->method() == m) {
1460             return data;
1461           }
1462         }
1463       }
1464       break;
1465     default:
1466       fatal("unexpected tag %d", dp->tag());
1467     }
1468   }
1469   return nullptr;
1470 }
1471 
1472 
1473 // Translate a bci to its corresponding extra data, or null.
1474 ProfileData* MethodData::bci_to_extra_data(int bci, Method* m, bool create_if_missing) {
1475   check_extra_data_locked();
1476 
1477   // This code assumes an entry for a SpeculativeTrapData is 2 cells
1478   assert(2*DataLayout::compute_size_in_bytes(BitData::static_cell_count()) ==
1479          DataLayout::compute_size_in_bytes(SpeculativeTrapData::static_cell_count()),
1480          "code needs to be adjusted");
1481 
1482   // Do not create one of these if method has been redefined.
1483   if (m != nullptr && m->is_old()) {
1484     return nullptr;
1485   }
1486 
1487   DataLayout* dp  = extra_data_base();
1488   DataLayout* end = args_data_limit();
1489 
1490   // Find if already exists
1491   ProfileData* result = bci_to_extra_data_find(bci, m, dp);
1492   if (result != nullptr || dp >= end) {
1493     return result;
1494   }
1495 
1496   if (create_if_missing) {
1497     // Not found -> Allocate
1498     assert(dp->tag() == DataLayout::no_tag || (dp->tag() == DataLayout::speculative_trap_data_tag && m != nullptr), "should be free");
1499     assert(next_extra(dp)->tag() == DataLayout::no_tag || next_extra(dp)->tag() == DataLayout::arg_info_data_tag, "should be free or arg info");
1500     u1 tag = m == nullptr ? DataLayout::bit_data_tag : DataLayout::speculative_trap_data_tag;
1501     // SpeculativeTrapData is 2 slots. Make sure we have room.
1502     if (m != nullptr && next_extra(dp)->tag() != DataLayout::no_tag) {
1503       return nullptr;
1504     }
1505     DataLayout temp;
1506     temp.initialize(tag, checked_cast<u2>(bci), 0);
1507 
1508     dp->set_header(temp.header());
1509     assert(dp->tag() == tag, "sane");
1510     assert(dp->bci() == bci, "no concurrent allocation");
1511     if (tag == DataLayout::bit_data_tag) {
1512       return new BitData(dp);
1513     } else {
1514       SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1515       data->set_method(m);
1516       return data;
1517     }
1518   }
1519   return nullptr;
1520 }
1521 
1522 ArgInfoData *MethodData::arg_info() {
1523   DataLayout* dp    = extra_data_base();
1524   DataLayout* end   = args_data_limit();
1525   for (; dp < end; dp = next_extra(dp)) {
1526     if (dp->tag() == DataLayout::arg_info_data_tag)
1527       return new ArgInfoData(dp);
1528   }
1529   return nullptr;
1530 }
1531 
1532 // Printing
1533 
1534 void MethodData::print_on(outputStream* st) const {
1535   assert(is_methodData(), "should be method data");
1536   st->print("method data for ");
1537   method()->print_value_on(st);
1538   st->cr();
1539   print_data_on(st);
1540 }
1541 
1542 void MethodData::print_value_on(outputStream* st) const {
1543   assert(is_methodData(), "should be method data");
1544   st->print("method data for ");
1545   method()->print_value_on(st);
1546 }
1547 
1548 void MethodData::print_data_on(outputStream* st) const {
1549   ResourceMark rm;
1550   ProfileData* data = first_data();
1551   if (_parameters_type_data_di != no_parameters) {
1552     parameters_type_data()->print_data_on(st);
1553   }
1554   for ( ; is_valid(data); data = next_data(data)) {
1555     st->print("%d", dp_to_di(data->dp()));
1556     st->fill_to(6);
1557     data->print_data_on(st, this);
1558   }
1559   st->print_cr("--- Extra data:");
1560   DataLayout* dp    = extra_data_base();
1561   DataLayout* end   = args_data_limit();
1562   for (;; dp = next_extra(dp)) {
1563     assert(dp < end, "moved past end of extra data");
1564     // No need for "Atomic::load_acquire" ops,
1565     // since the data structure is monotonic.
1566     switch(dp->tag()) {
1567     case DataLayout::no_tag:
1568       continue;
1569     case DataLayout::bit_data_tag:
1570       data = new BitData(dp);
1571       break;
1572     case DataLayout::speculative_trap_data_tag:
1573       data = new SpeculativeTrapData(dp);
1574       break;
1575     case DataLayout::arg_info_data_tag:
1576       data = new ArgInfoData(dp);
1577       dp = end; // ArgInfoData is at the end of extra data section.
1578       break;
1579     default:
1580       fatal("unexpected tag %d", dp->tag());
1581     }
1582     st->print("%d", dp_to_di(data->dp()));
1583     st->fill_to(6);
1584     data->print_data_on(st);
1585     if (dp >= end) return;
1586   }
1587 }
1588 
1589 // Verification
1590 
1591 void MethodData::verify_on(outputStream* st) {
1592   guarantee(is_methodData(), "object must be method data");
1593   // guarantee(m->is_perm(), "should be in permspace");
1594   this->verify_data_on(st);
1595 }
1596 
1597 void MethodData::verify_data_on(outputStream* st) {
1598   NEEDS_CLEANUP;
1599   // not yet implemented.
1600 }
1601 
1602 bool MethodData::profile_jsr292(const methodHandle& m, int bci) {
1603   if (m->is_compiled_lambda_form()) {
1604     return true;
1605   }
1606 
1607   Bytecode_invoke inv(m , bci);
1608   return inv.is_invokedynamic() || inv.is_invokehandle();
1609 }
1610 
1611 bool MethodData::profile_unsafe(const methodHandle& m, int bci) {
1612   Bytecode_invoke inv(m , bci);
1613   if (inv.is_invokevirtual()) {
1614     Symbol* klass = inv.klass();
1615     if (klass == vmSymbols::jdk_internal_misc_Unsafe() ||
1616         klass == vmSymbols::sun_misc_Unsafe() ||
1617         klass == vmSymbols::jdk_internal_misc_ScopedMemoryAccess()) {
1618       Symbol* name = inv.name();
1619       if (name->starts_with("get") || name->starts_with("put")) {
1620         return true;
1621       }
1622     }
1623   }
1624   return false;
1625 }
1626 
1627 int MethodData::profile_arguments_flag() {
1628   return TypeProfileLevel % 10;
1629 }
1630 
1631 bool MethodData::profile_arguments() {
1632   return profile_arguments_flag() > no_type_profile && profile_arguments_flag() <= type_profile_all && TypeProfileArgsLimit > 0;
1633 }
1634 
1635 bool MethodData::profile_arguments_jsr292_only() {
1636   return profile_arguments_flag() == type_profile_jsr292;
1637 }
1638 
1639 bool MethodData::profile_all_arguments() {
1640   return profile_arguments_flag() == type_profile_all;
1641 }
1642 
1643 bool MethodData::profile_arguments_for_invoke(const methodHandle& m, int bci) {
1644   if (!profile_arguments()) {
1645     return false;
1646   }
1647 
1648   if (profile_all_arguments()) {
1649     return true;
1650   }
1651 
1652   if (profile_unsafe(m, bci)) {
1653     return true;
1654   }
1655 
1656   assert(profile_arguments_jsr292_only(), "inconsistent");
1657   return profile_jsr292(m, bci);
1658 }
1659 
1660 int MethodData::profile_return_flag() {
1661   return (TypeProfileLevel % 100) / 10;
1662 }
1663 
1664 bool MethodData::profile_return() {
1665   return profile_return_flag() > no_type_profile && profile_return_flag() <= type_profile_all;
1666 }
1667 
1668 bool MethodData::profile_return_jsr292_only() {
1669   return profile_return_flag() == type_profile_jsr292;
1670 }
1671 
1672 bool MethodData::profile_all_return() {
1673   return profile_return_flag() == type_profile_all;
1674 }
1675 
1676 bool MethodData::profile_return_for_invoke(const methodHandle& m, int bci) {
1677   if (!profile_return()) {
1678     return false;
1679   }
1680 
1681   if (profile_all_return()) {
1682     return true;
1683   }
1684 
1685   assert(profile_return_jsr292_only(), "inconsistent");
1686   return profile_jsr292(m, bci);
1687 }
1688 
1689 int MethodData::profile_parameters_flag() {
1690   return TypeProfileLevel / 100;
1691 }
1692 
1693 bool MethodData::profile_parameters() {
1694   return profile_parameters_flag() > no_type_profile && profile_parameters_flag() <= type_profile_all;
1695 }
1696 
1697 bool MethodData::profile_parameters_jsr292_only() {
1698   return profile_parameters_flag() == type_profile_jsr292;
1699 }
1700 
1701 bool MethodData::profile_all_parameters() {
1702   return profile_parameters_flag() == type_profile_all;
1703 }
1704 
1705 bool MethodData::profile_parameters_for_method(const methodHandle& m) {
1706   if (!profile_parameters()) {
1707     return false;
1708   }
1709 
1710   if (profile_all_parameters()) {
1711     return true;
1712   }
1713 
1714   assert(profile_parameters_jsr292_only(), "inconsistent");
1715   return m->is_compiled_lambda_form();
1716 }
1717 
1718 void MethodData::metaspace_pointers_do(MetaspaceClosure* it) {
1719   log_trace(cds)("Iter(MethodData): %p", this);
1720   it->push(&_method);
1721 }
1722 
1723 void MethodData::clean_extra_data_helper(DataLayout* dp, int shift, bool reset) {
1724   check_extra_data_locked();
1725 
1726   if (shift == 0) {
1727     return;
1728   }
1729   if (!reset) {
1730     // Move all cells of trap entry at dp left by "shift" cells
1731     intptr_t* start = (intptr_t*)dp;
1732     intptr_t* end = (intptr_t*)next_extra(dp);
1733     for (intptr_t* ptr = start; ptr < end; ptr++) {
1734       *(ptr-shift) = *ptr;
1735     }
1736   } else {
1737     // Reset "shift" cells stopping at dp
1738     intptr_t* start = ((intptr_t*)dp) - shift;
1739     intptr_t* end = (intptr_t*)dp;
1740     for (intptr_t* ptr = start; ptr < end; ptr++) {
1741       *ptr = 0;
1742     }
1743   }
1744 }
1745 
1746 // Check for entries that reference an unloaded method
1747 class CleanExtraDataKlassClosure : public CleanExtraDataClosure {
1748   bool _always_clean;
1749 public:
1750   CleanExtraDataKlassClosure(bool always_clean) : _always_clean(always_clean) {}
1751   bool is_live(Method* m) {
1752     return !(_always_clean) && m->method_holder()->is_loader_alive();
1753   }
1754 };
1755 
1756 // Check for entries that reference a redefined method
1757 class CleanExtraDataMethodClosure : public CleanExtraDataClosure {
1758 public:
1759   CleanExtraDataMethodClosure() {}
1760   bool is_live(Method* m) { return !m->is_old(); }
1761 };
1762 
1763 
1764 // Remove SpeculativeTrapData entries that reference an unloaded or
1765 // redefined method
1766 void MethodData::clean_extra_data(CleanExtraDataClosure* cl) {
1767   check_extra_data_locked();
1768 
1769   DataLayout* dp  = extra_data_base();
1770   DataLayout* end = args_data_limit();
1771 
1772   int shift = 0;
1773   for (; dp < end; dp = next_extra(dp)) {
1774     switch(dp->tag()) {
1775     case DataLayout::speculative_trap_data_tag: {
1776       SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1777       Method* m = data->method();
1778       assert(m != nullptr, "should have a method");
1779       if (!cl->is_live(m)) {
1780         // "shift" accumulates the number of cells for dead
1781         // SpeculativeTrapData entries that have been seen so
1782         // far. Following entries must be shifted left by that many
1783         // cells to remove the dead SpeculativeTrapData entries.
1784         shift += (int)((intptr_t*)next_extra(dp) - (intptr_t*)dp);
1785       } else {
1786         // Shift this entry left if it follows dead
1787         // SpeculativeTrapData entries
1788         clean_extra_data_helper(dp, shift);
1789       }
1790       break;
1791     }
1792     case DataLayout::bit_data_tag:
1793       // Shift this entry left if it follows dead SpeculativeTrapData
1794       // entries
1795       clean_extra_data_helper(dp, shift);
1796       continue;
1797     case DataLayout::no_tag:
1798     case DataLayout::arg_info_data_tag:
1799       // We are at end of the live trap entries. The previous "shift"
1800       // cells contain entries that are either dead or were shifted
1801       // left. They need to be reset to no_tag
1802       clean_extra_data_helper(dp, shift, true);
1803       return;
1804     default:
1805       fatal("unexpected tag %d", dp->tag());
1806     }
1807   }
1808 }
1809 
1810 // Verify there's no unloaded or redefined method referenced by a
1811 // SpeculativeTrapData entry
1812 void MethodData::verify_extra_data_clean(CleanExtraDataClosure* cl) {
1813   check_extra_data_locked();
1814 
1815 #ifdef ASSERT
1816   DataLayout* dp  = extra_data_base();
1817   DataLayout* end = args_data_limit();
1818 
1819   for (; dp < end; dp = next_extra(dp)) {
1820     switch(dp->tag()) {
1821     case DataLayout::speculative_trap_data_tag: {
1822       SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1823       Method* m = data->method();
1824       assert(m != nullptr && cl->is_live(m), "Method should exist");
1825       break;
1826     }
1827     case DataLayout::bit_data_tag:
1828       continue;
1829     case DataLayout::no_tag:
1830     case DataLayout::arg_info_data_tag:
1831       return;
1832     default:
1833       fatal("unexpected tag %d", dp->tag());
1834     }
1835   }
1836 #endif
1837 }
1838 
1839 void MethodData::clean_method_data(bool always_clean) {
1840   ResourceMark rm;
1841   for (ProfileData* data = first_data();
1842        is_valid(data);
1843        data = next_data(data)) {
1844     data->clean_weak_klass_links(always_clean);
1845   }
1846   ParametersTypeData* parameters = parameters_type_data();
1847   if (parameters != nullptr) {
1848     parameters->clean_weak_klass_links(always_clean);
1849   }
1850 
1851   CleanExtraDataKlassClosure cl(always_clean);
1852 
1853   // Lock to modify extra data, and prevent Safepoint from breaking the lock
1854   MutexLocker ml(extra_data_lock(), Mutex::_no_safepoint_check_flag);
1855 
1856   clean_extra_data(&cl);
1857   verify_extra_data_clean(&cl);
1858 }
1859 
1860 // This is called during redefinition to clean all "old" redefined
1861 // methods out of MethodData for all methods.
1862 void MethodData::clean_weak_method_links() {
1863   ResourceMark rm;
1864   CleanExtraDataMethodClosure cl;
1865 
1866   // Lock to modify extra data, and prevent Safepoint from breaking the lock
1867   MutexLocker ml(extra_data_lock(), Mutex::_no_safepoint_check_flag);
1868 
1869   clean_extra_data(&cl);
1870   verify_extra_data_clean(&cl);
1871 }
1872 
1873 void MethodData::deallocate_contents(ClassLoaderData* loader_data) {
1874   release_C_heap_structures();
1875 }
1876 
1877 void MethodData::release_C_heap_structures() {
1878 #if INCLUDE_JVMCI
1879   FailedSpeculation::free_failed_speculations(get_failed_speculations_address());
1880 #endif
1881 }
1882 
1883 #ifdef ASSERT
1884 void MethodData::check_extra_data_locked() const {
1885     // Cast const away, just to be able to verify the lock
1886     // Usually we only want non-const accesses on the lock,
1887     // so this here is an exception.
1888     MethodData* self = (MethodData*)this;
1889     assert(self->extra_data_lock()->owned_by_self(), "must have lock");
1890     assert(!Thread::current()->is_Java_thread() ||
1891            JavaThread::current()->is_in_no_safepoint_scope(),
1892            "JavaThread must have NoSafepointVerifier inside lock scope");
1893 }
1894 #endif