1 /*
   2  * Copyright (c) 2000, 2013, 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 "classfile/systemDictionary.hpp"
  27 #include "interpreter/bytecode.hpp"
  28 #include "interpreter/bytecodeStream.hpp"
  29 #include "interpreter/linkResolver.hpp"
  30 #include "memory/heapInspection.hpp"
  31 #include "oops/methodData.hpp"
  32 #include "prims/jvmtiRedefineClasses.hpp"
  33 #include "runtime/compilationPolicy.hpp"
  34 #include "runtime/deoptimization.hpp"
  35 #include "runtime/handles.inline.hpp"
  36 
  37 // ==================================================================
  38 // DataLayout
  39 //
  40 // Overlay for generic profiling data.
  41 
  42 // Some types of data layouts need a length field.
  43 bool DataLayout::needs_array_len(u1 tag) {
  44   return (tag == multi_branch_data_tag) || (tag == arg_info_data_tag) || (tag == parameters_type_data_tag);
  45 }
  46 
  47 // Perform generic initialization of the data.  More specific
  48 // initialization occurs in overrides of ProfileData::post_initialize.
  49 void DataLayout::initialize(u1 tag, u2 bci, int cell_count) {
  50   _header._bits = (intptr_t)0;
  51   _header._struct._tag = tag;
  52   _header._struct._bci = bci;
  53   for (int i = 0; i < cell_count; i++) {
  54     set_cell_at(i, (intptr_t)0);
  55   }
  56   if (needs_array_len(tag)) {
  57     set_cell_at(ArrayData::array_len_off_set, cell_count - 1); // -1 for header.
  58   }
  59   if (tag == call_type_data_tag) {
  60     CallTypeData::initialize(this, cell_count);
  61   } else if (tag == virtual_call_type_data_tag) {
  62     VirtualCallTypeData::initialize(this, cell_count);
  63   }
  64 }
  65 
  66 void DataLayout::clean_weak_klass_links(BoolObjectClosure* cl) {
  67   ResourceMark m;
  68   data_in()->clean_weak_klass_links(cl);
  69 }
  70 
  71 
  72 // ==================================================================
  73 // ProfileData
  74 //
  75 // A ProfileData object is created to refer to a section of profiling
  76 // data in a structured way.
  77 
  78 // Constructor for invalid ProfileData.
  79 ProfileData::ProfileData() {
  80   _data = NULL;
  81 }
  82 
  83 char* ProfileData::print_data_on_helper(const MethodData* md) const {
  84   DataLayout* dp  = md->extra_data_base();
  85   DataLayout* end = md->extra_data_limit();
  86   stringStream ss;
  87   for (;; dp = MethodData::next_extra(dp)) {
  88     assert(dp < end, "moved past end of extra data");
  89     switch(dp->tag()) {
  90     case DataLayout::speculative_trap_data_tag:
  91       if (dp->bci() == bci()) {
  92         SpeculativeTrapData* data = new SpeculativeTrapData(dp);
  93         int trap = data->trap_state();
  94         char buf[100];
  95         ss.print("trap/");
  96         data->method()->print_short_name(&ss);
  97         ss.print("(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));
  98       }
  99       break;
 100     case DataLayout::bit_data_tag:
 101       break;
 102     case DataLayout::no_tag:
 103     case DataLayout::arg_info_data_tag:
 104       return ss.as_string();
 105       break;
 106     default:
 107       fatal(err_msg("unexpected tag %d", dp->tag()));
 108     }
 109   }
 110   return NULL;
 111 }
 112 
 113 void ProfileData::print_data_on(outputStream* st, const MethodData* md) const {
 114   print_data_on(st, print_data_on_helper(md));
 115 }
 116 
 117 #ifndef PRODUCT
 118 void ProfileData::print_shared(outputStream* st, const char* name, const char* extra) const {
 119   st->print("bci: %d", bci());
 120   st->fill_to(tab_width_one);
 121   st->print("%s", name);
 122   tab(st);
 123   int trap = trap_state();
 124   if (trap != 0) {
 125     char buf[100];
 126     st->print("trap(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));
 127   }
 128   if (extra != NULL) {
 129     st->print(extra);
 130   }
 131   int flags = data()->flags();
 132   if (flags != 0) {
 133     st->print("flags(%d) ", flags);
 134   }
 135 }
 136 
 137 void ProfileData::tab(outputStream* st, bool first) const {
 138   st->fill_to(first ? tab_width_one : tab_width_two);
 139 }
 140 #endif // !PRODUCT
 141 
 142 // ==================================================================
 143 // BitData
 144 //
 145 // A BitData corresponds to a one-bit flag.  This is used to indicate
 146 // whether a checkcast bytecode has seen a null value.
 147 
 148 
 149 #ifndef PRODUCT
 150 void BitData::print_data_on(outputStream* st, const char* extra) const {
 151   print_shared(st, "BitData", extra);
 152 }
 153 #endif // !PRODUCT
 154 
 155 // ==================================================================
 156 // CounterData
 157 //
 158 // A CounterData corresponds to a simple counter.
 159 
 160 #ifndef PRODUCT
 161 void CounterData::print_data_on(outputStream* st, const char* extra) const {
 162   print_shared(st, "CounterData", extra);
 163   st->print_cr("count(%u)", count());
 164 }
 165 #endif // !PRODUCT
 166 
 167 // ==================================================================
 168 // JumpData
 169 //
 170 // A JumpData is used to access profiling information for a direct
 171 // branch.  It is a counter, used for counting the number of branches,
 172 // plus a data displacement, used for realigning the data pointer to
 173 // the corresponding target bci.
 174 
 175 void JumpData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 176   assert(stream->bci() == bci(), "wrong pos");
 177   int target;
 178   Bytecodes::Code c = stream->code();
 179   if (c == Bytecodes::_goto_w || c == Bytecodes::_jsr_w) {
 180     target = stream->dest_w();
 181   } else {
 182     target = stream->dest();
 183   }
 184   int my_di = mdo->dp_to_di(dp());
 185   int target_di = mdo->bci_to_di(target);
 186   int offset = target_di - my_di;
 187   set_displacement(offset);
 188 }
 189 
 190 #ifndef PRODUCT
 191 void JumpData::print_data_on(outputStream* st, const char* extra) const {
 192   print_shared(st, "JumpData", extra);
 193   st->print_cr("taken(%u) displacement(%d)", taken(), displacement());
 194 }
 195 #endif // !PRODUCT
 196 
 197 int TypeStackSlotEntries::compute_cell_count(Symbol* signature, bool include_receiver, int max) {
 198   // Parameter profiling include the receiver
 199   int args_count = include_receiver ? 1 : 0;
 200   ResourceMark rm;
 201   SignatureStream ss(signature);
 202   args_count += ss.reference_parameter_count();
 203   args_count = MIN2(args_count, max);
 204   return args_count * per_arg_cell_count;
 205 }
 206 
 207 int TypeEntriesAtCall::compute_cell_count(BytecodeStream* stream) {
 208   assert(Bytecodes::is_invoke(stream->code()), "should be invoke");
 209   assert(TypeStackSlotEntries::per_arg_count() > ReturnTypeEntry::static_cell_count(), "code to test for arguments/results broken");
 210   Bytecode_invoke inv(stream->method(), stream->bci());
 211   int args_cell = 0;
 212   if (arguments_profiling_enabled()) {
 213     args_cell = TypeStackSlotEntries::compute_cell_count(inv.signature(), false, TypeProfileArgsLimit);
 214   }
 215   int ret_cell = 0;
 216   if (return_profiling_enabled() && (inv.result_type() == T_OBJECT || inv.result_type() == T_ARRAY)) {
 217     ret_cell = ReturnTypeEntry::static_cell_count();
 218   }
 219   int header_cell = 0;
 220   if (args_cell + ret_cell > 0) {
 221     header_cell = header_cell_count();
 222   }
 223 
 224   return header_cell + args_cell + ret_cell;
 225 }
 226 
 227 class ArgumentOffsetComputer : public SignatureInfo {
 228 private:
 229   int _max;
 230   GrowableArray<int> _offsets;
 231 
 232   void set(int size, BasicType type) { _size += size; }
 233   void do_object(int begin, int end) {
 234     if (_offsets.length() < _max) {
 235       _offsets.push(_size);
 236     }
 237     SignatureInfo::do_object(begin, end);
 238   }
 239   void do_array (int begin, int end) {
 240     if (_offsets.length() < _max) {
 241       _offsets.push(_size);
 242     }
 243     SignatureInfo::do_array(begin, end);
 244   }
 245 
 246 public:
 247   ArgumentOffsetComputer(Symbol* signature, int max)
 248     : SignatureInfo(signature), _max(max), _offsets(Thread::current(), max) {
 249   }
 250 
 251   int total() { lazy_iterate_parameters(); return _size; }
 252 
 253   int off_at(int i) const { return _offsets.at(i); }
 254 };
 255 
 256 void TypeStackSlotEntries::post_initialize(Symbol* signature, bool has_receiver, bool include_receiver) {
 257   ResourceMark rm;
 258   int start = 0;
 259   // Parameter profiling include the receiver
 260   if (include_receiver && has_receiver) {
 261     set_stack_slot(0, 0);
 262     set_type(0, type_none());
 263     start += 1;
 264   }
 265   ArgumentOffsetComputer aos(signature, _number_of_entries-start);
 266   aos.total();
 267   for (int i = start; i < _number_of_entries; i++) {
 268     set_stack_slot(i, aos.off_at(i-start) + (has_receiver ? 1 : 0));
 269     set_type(i, type_none());
 270   }
 271 }
 272 
 273 void CallTypeData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 274   assert(Bytecodes::is_invoke(stream->code()), "should be invoke");
 275   Bytecode_invoke inv(stream->method(), stream->bci());
 276 
 277   SignatureStream ss(inv.signature());
 278   if (has_arguments()) {
 279 #ifdef ASSERT
 280     ResourceMark rm;
 281     int count = MIN2(ss.reference_parameter_count(), (int)TypeProfileArgsLimit);
 282     assert(count > 0, "room for args type but none found?");
 283     check_number_of_arguments(count);
 284 #endif
 285     _args.post_initialize(inv.signature(), inv.has_receiver(), false);
 286   }
 287 
 288   if (has_return()) {
 289     assert(inv.result_type() == T_OBJECT || inv.result_type() == T_ARRAY, "room for a ret type but doesn't return obj?");
 290     _ret.post_initialize();
 291   }
 292 }
 293 
 294 void VirtualCallTypeData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 295   assert(Bytecodes::is_invoke(stream->code()), "should be invoke");
 296   Bytecode_invoke inv(stream->method(), stream->bci());
 297 
 298   if (has_arguments()) {
 299 #ifdef ASSERT
 300     ResourceMark rm;
 301     SignatureStream ss(inv.signature());
 302     int count = MIN2(ss.reference_parameter_count(), (int)TypeProfileArgsLimit);
 303     assert(count > 0, "room for args type but none found?");
 304     check_number_of_arguments(count);
 305 #endif
 306     _args.post_initialize(inv.signature(), inv.has_receiver(), false);
 307   }
 308 
 309   if (has_return()) {
 310     assert(inv.result_type() == T_OBJECT || inv.result_type() == T_ARRAY, "room for a ret type but doesn't return obj?");
 311     _ret.post_initialize();
 312   }
 313 }
 314 
 315 bool TypeEntries::is_loader_alive(BoolObjectClosure* is_alive_cl, intptr_t p) {
 316   Klass* k = (Klass*)klass_part(p);
 317   return k != NULL && k->is_loader_alive(is_alive_cl);
 318 }
 319 
 320 void TypeStackSlotEntries::clean_weak_klass_links(BoolObjectClosure* is_alive_cl) {
 321   for (int i = 0; i < _number_of_entries; i++) {
 322     intptr_t p = type(i);
 323     if (!is_loader_alive(is_alive_cl, p)) {
 324       set_type(i, with_status((Klass*)NULL, p));
 325     }
 326   }
 327 }
 328 
 329 void ReturnTypeEntry::clean_weak_klass_links(BoolObjectClosure* is_alive_cl) {
 330   intptr_t p = type();
 331   if (!is_loader_alive(is_alive_cl, p)) {
 332     set_type(with_status((Klass*)NULL, p));
 333   }
 334 }
 335 
 336 bool TypeEntriesAtCall::return_profiling_enabled() {
 337   return MethodData::profile_return();
 338 }
 339 
 340 bool TypeEntriesAtCall::arguments_profiling_enabled() {
 341   return MethodData::profile_arguments();
 342 }
 343 
 344 #ifndef PRODUCT
 345 void TypeEntries::print_klass(outputStream* st, intptr_t k) {
 346   if (is_type_none(k)) {
 347     st->print("none");
 348   } else if (is_type_unknown(k)) {
 349     st->print("unknown");
 350   } else {
 351     valid_klass(k)->print_value_on(st);
 352   }
 353   if (was_null_seen(k)) {
 354     st->print(" (null seen)");
 355   }
 356 }
 357 
 358 void TypeStackSlotEntries::print_data_on(outputStream* st) const {
 359   for (int i = 0; i < _number_of_entries; i++) {
 360     _pd->tab(st);
 361     st->print("%d: stack(%u) ", i, stack_slot(i));
 362     print_klass(st, type(i));
 363     st->cr();
 364   }
 365 }
 366 
 367 void ReturnTypeEntry::print_data_on(outputStream* st) const {
 368   _pd->tab(st);
 369   print_klass(st, type());
 370   st->cr();
 371 }
 372 
 373 void CallTypeData::print_data_on(outputStream* st, const char* extra) const {
 374   CounterData::print_data_on(st, extra);
 375   if (has_arguments()) {
 376     tab(st, true);
 377     st->print("argument types");
 378     _args.print_data_on(st);
 379   }
 380   if (has_return()) {
 381     tab(st, true);
 382     st->print("return type");
 383     _ret.print_data_on(st);
 384   }
 385 }
 386 
 387 void VirtualCallTypeData::print_data_on(outputStream* st, const char* extra) const {
 388   VirtualCallData::print_data_on(st, extra);
 389   if (has_arguments()) {
 390     tab(st, true);
 391     st->print("argument types");
 392     _args.print_data_on(st);
 393   }
 394   if (has_return()) {
 395     tab(st, true);
 396     st->print("return type");
 397     _ret.print_data_on(st);
 398   }
 399 }
 400 #endif
 401 
 402 // ==================================================================
 403 // ReceiverTypeData
 404 //
 405 // A ReceiverTypeData is used to access profiling information about a
 406 // dynamic type check.  It consists of a counter which counts the total times
 407 // that the check is reached, and a series of (Klass*, count) pairs
 408 // which are used to store a type profile for the receiver of the check.
 409 
 410 void ReceiverTypeData::clean_weak_klass_links(BoolObjectClosure* is_alive_cl) {
 411     for (uint row = 0; row < row_limit(); row++) {
 412     Klass* p = receiver(row);
 413     if (p != NULL && !p->is_loader_alive(is_alive_cl)) {
 414       clear_row(row);
 415     }
 416   }
 417 }
 418 
 419 #ifndef PRODUCT
 420 void ReceiverTypeData::print_receiver_data_on(outputStream* st) const {
 421   uint row;
 422   int entries = 0;
 423   for (row = 0; row < row_limit(); row++) {
 424     if (receiver(row) != NULL)  entries++;
 425   }
 426   st->print_cr("count(%u) entries(%u)", count(), entries);
 427   int total = count();
 428   for (row = 0; row < row_limit(); row++) {
 429     if (receiver(row) != NULL) {
 430       total += receiver_count(row);
 431     }
 432   }
 433   for (row = 0; row < row_limit(); row++) {
 434     if (receiver(row) != NULL) {
 435       tab(st);
 436       receiver(row)->print_value_on(st);
 437       st->print_cr("(%u %4.2f)", receiver_count(row), (float) receiver_count(row) / (float) total);
 438     }
 439   }
 440 }
 441 void ReceiverTypeData::print_data_on(outputStream* st, const char* extra) const {
 442   print_shared(st, "ReceiverTypeData", extra);
 443   print_receiver_data_on(st);
 444 }
 445 void VirtualCallData::print_data_on(outputStream* st, const char* extra) const {
 446   print_shared(st, "VirtualCallData", extra);
 447   print_receiver_data_on(st);
 448 }
 449 #endif // !PRODUCT
 450 
 451 // ==================================================================
 452 // RetData
 453 //
 454 // A RetData is used to access profiling information for a ret bytecode.
 455 // It is composed of a count of the number of times that the ret has
 456 // been executed, followed by a series of triples of the form
 457 // (bci, count, di) which count the number of times that some bci was the
 458 // target of the ret and cache a corresponding displacement.
 459 
 460 void RetData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 461   for (uint row = 0; row < row_limit(); row++) {
 462     set_bci_displacement(row, -1);
 463     set_bci(row, no_bci);
 464   }
 465   // release so other threads see a consistent state.  bci is used as
 466   // a valid flag for bci_displacement.
 467   OrderAccess::release();
 468 }
 469 
 470 // This routine needs to atomically update the RetData structure, so the
 471 // caller needs to hold the RetData_lock before it gets here.  Since taking
 472 // the lock can block (and allow GC) and since RetData is a ProfileData is a
 473 // wrapper around a derived oop, taking the lock in _this_ method will
 474 // basically cause the 'this' pointer's _data field to contain junk after the
 475 // lock.  We require the caller to take the lock before making the ProfileData
 476 // structure.  Currently the only caller is InterpreterRuntime::update_mdp_for_ret
 477 address RetData::fixup_ret(int return_bci, MethodData* h_mdo) {
 478   // First find the mdp which corresponds to the return bci.
 479   address mdp = h_mdo->bci_to_dp(return_bci);
 480 
 481   // Now check to see if any of the cache slots are open.
 482   for (uint row = 0; row < row_limit(); row++) {
 483     if (bci(row) == no_bci) {
 484       set_bci_displacement(row, mdp - dp());
 485       set_bci_count(row, DataLayout::counter_increment);
 486       // Barrier to ensure displacement is written before the bci; allows
 487       // the interpreter to read displacement without fear of race condition.
 488       release_set_bci(row, return_bci);
 489       break;
 490     }
 491   }
 492   return mdp;
 493 }
 494 
 495 
 496 #ifndef PRODUCT
 497 void RetData::print_data_on(outputStream* st, const char* extra) const {
 498   print_shared(st, "RetData", extra);
 499   uint row;
 500   int entries = 0;
 501   for (row = 0; row < row_limit(); row++) {
 502     if (bci(row) != no_bci)  entries++;
 503   }
 504   st->print_cr("count(%u) entries(%u)", count(), entries);
 505   for (row = 0; row < row_limit(); row++) {
 506     if (bci(row) != no_bci) {
 507       tab(st);
 508       st->print_cr("bci(%d: count(%u) displacement(%d))",
 509                    bci(row), bci_count(row), bci_displacement(row));
 510     }
 511   }
 512 }
 513 #endif // !PRODUCT
 514 
 515 // ==================================================================
 516 // BranchData
 517 //
 518 // A BranchData is used to access profiling data for a two-way branch.
 519 // It consists of taken and not_taken counts as well as a data displacement
 520 // for the taken case.
 521 
 522 void BranchData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 523   assert(stream->bci() == bci(), "wrong pos");
 524   int target = stream->dest();
 525   int my_di = mdo->dp_to_di(dp());
 526   int target_di = mdo->bci_to_di(target);
 527   int offset = target_di - my_di;
 528   set_displacement(offset);
 529 }
 530 
 531 #ifndef PRODUCT
 532 void BranchData::print_data_on(outputStream* st, const char* extra) const {
 533   print_shared(st, "BranchData", extra);
 534   st->print_cr("taken(%u) displacement(%d)",
 535                taken(), displacement());
 536   tab(st);
 537   st->print_cr("not taken(%u)", not_taken());
 538 }
 539 #endif
 540 
 541 // ==================================================================
 542 // MultiBranchData
 543 //
 544 // A MultiBranchData is used to access profiling information for
 545 // a multi-way branch (*switch bytecodes).  It consists of a series
 546 // of (count, displacement) pairs, which count the number of times each
 547 // case was taken and specify the data displacment for each branch target.
 548 
 549 int MultiBranchData::compute_cell_count(BytecodeStream* stream) {
 550   int cell_count = 0;
 551   if (stream->code() == Bytecodes::_tableswitch) {
 552     Bytecode_tableswitch sw(stream->method()(), stream->bcp());
 553     cell_count = 1 + per_case_cell_count * (1 + sw.length()); // 1 for default
 554   } else {
 555     Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
 556     cell_count = 1 + per_case_cell_count * (sw.number_of_pairs() + 1); // 1 for default
 557   }
 558   return cell_count;
 559 }
 560 
 561 void MultiBranchData::post_initialize(BytecodeStream* stream,
 562                                       MethodData* mdo) {
 563   assert(stream->bci() == bci(), "wrong pos");
 564   int target;
 565   int my_di;
 566   int target_di;
 567   int offset;
 568   if (stream->code() == Bytecodes::_tableswitch) {
 569     Bytecode_tableswitch sw(stream->method()(), stream->bcp());
 570     int len = sw.length();
 571     assert(array_len() == per_case_cell_count * (len + 1), "wrong len");
 572     for (int count = 0; count < len; count++) {
 573       target = sw.dest_offset_at(count) + bci();
 574       my_di = mdo->dp_to_di(dp());
 575       target_di = mdo->bci_to_di(target);
 576       offset = target_di - my_di;
 577       set_displacement_at(count, offset);
 578     }
 579     target = sw.default_offset() + bci();
 580     my_di = mdo->dp_to_di(dp());
 581     target_di = mdo->bci_to_di(target);
 582     offset = target_di - my_di;
 583     set_default_displacement(offset);
 584 
 585   } else {
 586     Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
 587     int npairs = sw.number_of_pairs();
 588     assert(array_len() == per_case_cell_count * (npairs + 1), "wrong len");
 589     for (int count = 0; count < npairs; count++) {
 590       LookupswitchPair pair = sw.pair_at(count);
 591       target = pair.offset() + bci();
 592       my_di = mdo->dp_to_di(dp());
 593       target_di = mdo->bci_to_di(target);
 594       offset = target_di - my_di;
 595       set_displacement_at(count, offset);
 596     }
 597     target = sw.default_offset() + bci();
 598     my_di = mdo->dp_to_di(dp());
 599     target_di = mdo->bci_to_di(target);
 600     offset = target_di - my_di;
 601     set_default_displacement(offset);
 602   }
 603 }
 604 
 605 #ifndef PRODUCT
 606 void MultiBranchData::print_data_on(outputStream* st, const char* extra) const {
 607   print_shared(st, "MultiBranchData", extra);
 608   st->print_cr("default_count(%u) displacement(%d)",
 609                default_count(), default_displacement());
 610   int cases = number_of_cases();
 611   for (int i = 0; i < cases; i++) {
 612     tab(st);
 613     st->print_cr("count(%u) displacement(%d)",
 614                  count_at(i), displacement_at(i));
 615   }
 616 }
 617 #endif
 618 
 619 #ifndef PRODUCT
 620 void ArgInfoData::print_data_on(outputStream* st, const char* extra) const {
 621   print_shared(st, "ArgInfoData", extra);
 622   int nargs = number_of_args();
 623   for (int i = 0; i < nargs; i++) {
 624     st->print("  0x%x", arg_modified(i));
 625   }
 626   st->cr();
 627 }
 628 
 629 #endif
 630 
 631 int ParametersTypeData::compute_cell_count(Method* m) {
 632   if (!MethodData::profile_parameters_for_method(m)) {
 633     return 0;
 634   }
 635   int max = TypeProfileParmsLimit == -1 ? INT_MAX : TypeProfileParmsLimit;
 636   int obj_args = TypeStackSlotEntries::compute_cell_count(m->signature(), !m->is_static(), max);
 637   if (obj_args > 0) {
 638     return obj_args + 1; // 1 cell for array len
 639   }
 640   return 0;
 641 }
 642 
 643 void ParametersTypeData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
 644   _parameters.post_initialize(mdo->method()->signature(), !mdo->method()->is_static(), true);
 645 }
 646 
 647 bool ParametersTypeData::profiling_enabled() {
 648   return MethodData::profile_parameters();
 649 }
 650 
 651 #ifndef PRODUCT
 652 void ParametersTypeData::print_data_on(outputStream* st, const char* extra) const {
 653   st->print("parameter types", extra);
 654   _parameters.print_data_on(st);
 655 }
 656 
 657 void SpeculativeTrapData::print_data_on(outputStream* st, const char* extra) const {
 658   print_shared(st, "SpeculativeTrapData", extra);
 659   tab(st);
 660   method()->print_short_name(st);
 661   st->cr();
 662 }
 663 #endif
 664 
 665 // ==================================================================
 666 // MethodData*
 667 //
 668 // A MethodData* holds information which has been collected about
 669 // a method.
 670 
 671 MethodData* MethodData::allocate(ClassLoaderData* loader_data, methodHandle method, TRAPS) {
 672   int size = MethodData::compute_allocation_size_in_words(method);
 673 
 674   return new (loader_data, size, false, MetaspaceObj::MethodDataType, THREAD)
 675     MethodData(method(), size, CHECK_NULL);
 676 }
 677 
 678 int MethodData::bytecode_cell_count(Bytecodes::Code code) {
 679 #if defined(COMPILER1) && !defined(COMPILER2)
 680   return no_profile_data;
 681 #else
 682   switch (code) {
 683   case Bytecodes::_checkcast:
 684   case Bytecodes::_instanceof:
 685   case Bytecodes::_aastore:
 686     if (TypeProfileCasts) {
 687       return ReceiverTypeData::static_cell_count();
 688     } else {
 689       return BitData::static_cell_count();
 690     }
 691   case Bytecodes::_invokespecial:
 692   case Bytecodes::_invokestatic:
 693     if (MethodData::profile_arguments() || MethodData::profile_return()) {
 694       return variable_cell_count;
 695     } else {
 696       return CounterData::static_cell_count();
 697     }
 698   case Bytecodes::_goto:
 699   case Bytecodes::_goto_w:
 700   case Bytecodes::_jsr:
 701   case Bytecodes::_jsr_w:
 702     return JumpData::static_cell_count();
 703   case Bytecodes::_invokevirtual:
 704   case Bytecodes::_invokeinterface:
 705     if (MethodData::profile_arguments() || MethodData::profile_return()) {
 706       return variable_cell_count;
 707     } else {
 708       return VirtualCallData::static_cell_count();
 709     }
 710   case Bytecodes::_invokedynamic:
 711     if (MethodData::profile_arguments() || MethodData::profile_return()) {
 712       return variable_cell_count;
 713     } else {
 714       return CounterData::static_cell_count();
 715     }
 716   case Bytecodes::_ret:
 717     return RetData::static_cell_count();
 718   case Bytecodes::_ifeq:
 719   case Bytecodes::_ifne:
 720   case Bytecodes::_iflt:
 721   case Bytecodes::_ifge:
 722   case Bytecodes::_ifgt:
 723   case Bytecodes::_ifle:
 724   case Bytecodes::_if_icmpeq:
 725   case Bytecodes::_if_icmpne:
 726   case Bytecodes::_if_icmplt:
 727   case Bytecodes::_if_icmpge:
 728   case Bytecodes::_if_icmpgt:
 729   case Bytecodes::_if_icmple:
 730   case Bytecodes::_if_acmpeq:
 731   case Bytecodes::_if_acmpne:
 732   case Bytecodes::_ifnull:
 733   case Bytecodes::_ifnonnull:
 734     return BranchData::static_cell_count();
 735   case Bytecodes::_lookupswitch:
 736   case Bytecodes::_tableswitch:
 737     return variable_cell_count;
 738   }
 739   return no_profile_data;
 740 #endif
 741 }
 742 
 743 // Compute the size of the profiling information corresponding to
 744 // the current bytecode.
 745 int MethodData::compute_data_size(BytecodeStream* stream) {
 746   int cell_count = bytecode_cell_count(stream->code());
 747   if (cell_count == no_profile_data) {
 748     return 0;
 749   }
 750   if (cell_count == variable_cell_count) {
 751     switch (stream->code()) {
 752     case Bytecodes::_lookupswitch:
 753     case Bytecodes::_tableswitch:
 754       cell_count = MultiBranchData::compute_cell_count(stream);
 755       break;
 756     case Bytecodes::_invokespecial:
 757     case Bytecodes::_invokestatic:
 758     case Bytecodes::_invokedynamic:
 759       assert(MethodData::profile_arguments() || MethodData::profile_return(), "should be collecting args profile");
 760       if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 761           profile_return_for_invoke(stream->method(), stream->bci())) {
 762         cell_count = CallTypeData::compute_cell_count(stream);
 763       } else {
 764         cell_count = CounterData::static_cell_count();
 765       }
 766       break;
 767     case Bytecodes::_invokevirtual:
 768     case Bytecodes::_invokeinterface: {
 769       assert(MethodData::profile_arguments() || MethodData::profile_return(), "should be collecting args profile");
 770       if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 771           profile_return_for_invoke(stream->method(), stream->bci())) {
 772         cell_count = VirtualCallTypeData::compute_cell_count(stream);
 773       } else {
 774         cell_count = VirtualCallData::static_cell_count();
 775       }
 776       break;
 777     }
 778     default:
 779       fatal("unexpected bytecode for var length profile data");
 780     }
 781   }
 782   // Note:  cell_count might be zero, meaning that there is just
 783   //        a DataLayout header, with no extra cells.
 784   assert(cell_count >= 0, "sanity");
 785   return DataLayout::compute_size_in_bytes(cell_count);
 786 }
 787 
 788 bool MethodData::is_speculative_trap_bytecode(Bytecodes::Code code) {
 789   // Bytecodes for which we may use speculation
 790   switch (code) {
 791   case Bytecodes::_checkcast:
 792   case Bytecodes::_instanceof:
 793   case Bytecodes::_aastore:
 794   case Bytecodes::_invokevirtual:
 795   case Bytecodes::_invokeinterface:
 796   case Bytecodes::_if_acmpeq:
 797   case Bytecodes::_if_acmpne:
 798   case Bytecodes::_invokestatic:
 799 #ifdef COMPILER2
 800     return UseTypeSpeculation;
 801 #endif
 802   default:
 803     return false;
 804   }
 805   return false;
 806 }
 807 
 808 int MethodData::compute_extra_data_count(int data_size, int empty_bc_count, bool needs_speculative_traps) {
 809   if (ProfileTraps) {
 810     // Assume that up to 3% of BCIs with no MDP will need to allocate one.
 811     int extra_data_count = (uint)(empty_bc_count * 3) / 128 + 1;
 812     // If the method is large, let the extra BCIs grow numerous (to ~1%).
 813     int one_percent_of_data
 814       = (uint)data_size / (DataLayout::header_size_in_bytes()*128);
 815     if (extra_data_count < one_percent_of_data)
 816       extra_data_count = one_percent_of_data;
 817     if (extra_data_count > empty_bc_count)
 818       extra_data_count = empty_bc_count;  // no need for more
 819 
 820     // Make sure we have a minimum number of extra data slots to
 821     // allocate SpeculativeTrapData entries. We would want to have one
 822     // entry per compilation that inlines this method and for which
 823     // some type speculation assumption fails. So the room we need for
 824     // the SpeculativeTrapData entries doesn't directly depend on the
 825     // size of the method. Because it's hard to estimate, we reserve
 826     // space for an arbitrary number of entries.
 827     int spec_data_count = (needs_speculative_traps ? SpecTrapLimitExtraEntries : 0) *
 828       (SpeculativeTrapData::static_cell_count() + DataLayout::header_size_in_cells());
 829 
 830     return MAX2(extra_data_count, spec_data_count);
 831   } else {
 832     return 0;
 833   }
 834 }
 835 
 836 // Compute the size of the MethodData* necessary to store
 837 // profiling information about a given method.  Size is in bytes.
 838 int MethodData::compute_allocation_size_in_bytes(methodHandle method) {
 839   int data_size = 0;
 840   BytecodeStream stream(method);
 841   Bytecodes::Code c;
 842   int empty_bc_count = 0;  // number of bytecodes lacking data
 843   bool needs_speculative_traps = false;
 844   while ((c = stream.next()) >= 0) {
 845     int size_in_bytes = compute_data_size(&stream);
 846     data_size += size_in_bytes;
 847     if (size_in_bytes == 0)  empty_bc_count += 1;
 848     needs_speculative_traps = needs_speculative_traps || is_speculative_trap_bytecode(c);
 849   }
 850   int object_size = in_bytes(data_offset()) + data_size;
 851 
 852   // Add some extra DataLayout cells (at least one) to track stray traps.
 853   int extra_data_count = compute_extra_data_count(data_size, empty_bc_count, needs_speculative_traps);
 854   object_size += extra_data_count * DataLayout::compute_size_in_bytes(0);
 855 
 856   // Add a cell to record information about modified arguments.
 857   int arg_size = method->size_of_parameters();
 858   object_size += DataLayout::compute_size_in_bytes(arg_size+1);
 859 
 860   // Reserve room for an area of the MDO dedicated to profiling of
 861   // parameters
 862   int args_cell = ParametersTypeData::compute_cell_count(method());
 863   if (args_cell > 0) {
 864     object_size += DataLayout::compute_size_in_bytes(args_cell);
 865   }
 866   return object_size;
 867 }
 868 
 869 // Compute the size of the MethodData* necessary to store
 870 // profiling information about a given method.  Size is in words
 871 int MethodData::compute_allocation_size_in_words(methodHandle method) {
 872   int byte_size = compute_allocation_size_in_bytes(method);
 873   int word_size = align_size_up(byte_size, BytesPerWord) / BytesPerWord;
 874   return align_object_size(word_size);
 875 }
 876 
 877 // Initialize an individual data segment.  Returns the size of
 878 // the segment in bytes.
 879 int MethodData::initialize_data(BytecodeStream* stream,
 880                                        int data_index) {
 881 #if defined(COMPILER1) && !defined(COMPILER2)
 882   return 0;
 883 #else
 884   int cell_count = -1;
 885   int tag = DataLayout::no_tag;
 886   DataLayout* data_layout = data_layout_at(data_index);
 887   Bytecodes::Code c = stream->code();
 888   switch (c) {
 889   case Bytecodes::_checkcast:
 890   case Bytecodes::_instanceof:
 891   case Bytecodes::_aastore:
 892     if (TypeProfileCasts) {
 893       cell_count = ReceiverTypeData::static_cell_count();
 894       tag = DataLayout::receiver_type_data_tag;
 895     } else {
 896       cell_count = BitData::static_cell_count();
 897       tag = DataLayout::bit_data_tag;
 898     }
 899     break;
 900   case Bytecodes::_invokespecial:
 901   case Bytecodes::_invokestatic: {
 902     int counter_data_cell_count = CounterData::static_cell_count();
 903     if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 904         profile_return_for_invoke(stream->method(), stream->bci())) {
 905       cell_count = CallTypeData::compute_cell_count(stream);
 906     } else {
 907       cell_count = counter_data_cell_count;
 908     }
 909     if (cell_count > counter_data_cell_count) {
 910       tag = DataLayout::call_type_data_tag;
 911     } else {
 912       tag = DataLayout::counter_data_tag;
 913     }
 914     break;
 915   }
 916   case Bytecodes::_goto:
 917   case Bytecodes::_goto_w:
 918   case Bytecodes::_jsr:
 919   case Bytecodes::_jsr_w:
 920     cell_count = JumpData::static_cell_count();
 921     tag = DataLayout::jump_data_tag;
 922     break;
 923   case Bytecodes::_invokevirtual:
 924   case Bytecodes::_invokeinterface: {
 925     int virtual_call_data_cell_count = VirtualCallData::static_cell_count();
 926     if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 927         profile_return_for_invoke(stream->method(), stream->bci())) {
 928       cell_count = VirtualCallTypeData::compute_cell_count(stream);
 929     } else {
 930       cell_count = virtual_call_data_cell_count;
 931     }
 932     if (cell_count > virtual_call_data_cell_count) {
 933       tag = DataLayout::virtual_call_type_data_tag;
 934     } else {
 935       tag = DataLayout::virtual_call_data_tag;
 936     }
 937     break;
 938   }
 939   case Bytecodes::_invokedynamic: {
 940     // %%% should make a type profile for any invokedynamic that takes a ref argument
 941     int counter_data_cell_count = CounterData::static_cell_count();
 942     if (profile_arguments_for_invoke(stream->method(), stream->bci()) ||
 943         profile_return_for_invoke(stream->method(), stream->bci())) {
 944       cell_count = CallTypeData::compute_cell_count(stream);
 945     } else {
 946       cell_count = counter_data_cell_count;
 947     }
 948     if (cell_count > counter_data_cell_count) {
 949       tag = DataLayout::call_type_data_tag;
 950     } else {
 951       tag = DataLayout::counter_data_tag;
 952     }
 953     break;
 954   }
 955   case Bytecodes::_ret:
 956     cell_count = RetData::static_cell_count();
 957     tag = DataLayout::ret_data_tag;
 958     break;
 959   case Bytecodes::_ifeq:
 960   case Bytecodes::_ifne:
 961   case Bytecodes::_iflt:
 962   case Bytecodes::_ifge:
 963   case Bytecodes::_ifgt:
 964   case Bytecodes::_ifle:
 965   case Bytecodes::_if_icmpeq:
 966   case Bytecodes::_if_icmpne:
 967   case Bytecodes::_if_icmplt:
 968   case Bytecodes::_if_icmpge:
 969   case Bytecodes::_if_icmpgt:
 970   case Bytecodes::_if_icmple:
 971   case Bytecodes::_if_acmpeq:
 972   case Bytecodes::_if_acmpne:
 973   case Bytecodes::_ifnull:
 974   case Bytecodes::_ifnonnull:
 975     cell_count = BranchData::static_cell_count();
 976     tag = DataLayout::branch_data_tag;
 977     break;
 978   case Bytecodes::_lookupswitch:
 979   case Bytecodes::_tableswitch:
 980     cell_count = MultiBranchData::compute_cell_count(stream);
 981     tag = DataLayout::multi_branch_data_tag;
 982     break;
 983   }
 984   assert(tag == DataLayout::multi_branch_data_tag ||
 985          ((MethodData::profile_arguments() || MethodData::profile_return()) &&
 986           (tag == DataLayout::call_type_data_tag ||
 987            tag == DataLayout::counter_data_tag ||
 988            tag == DataLayout::virtual_call_type_data_tag ||
 989            tag == DataLayout::virtual_call_data_tag)) ||
 990          cell_count == bytecode_cell_count(c), "cell counts must agree");
 991   if (cell_count >= 0) {
 992     assert(tag != DataLayout::no_tag, "bad tag");
 993     assert(bytecode_has_profile(c), "agree w/ BHP");
 994     data_layout->initialize(tag, stream->bci(), cell_count);
 995     return DataLayout::compute_size_in_bytes(cell_count);
 996   } else {
 997     assert(!bytecode_has_profile(c), "agree w/ !BHP");
 998     return 0;
 999   }
1000 #endif
1001 }
1002 
1003 // Get the data at an arbitrary (sort of) data index.
1004 ProfileData* MethodData::data_at(int data_index) const {
1005   if (out_of_bounds(data_index)) {
1006     return NULL;
1007   }
1008   DataLayout* data_layout = data_layout_at(data_index);
1009   return data_layout->data_in();
1010 }
1011 
1012 ProfileData* DataLayout::data_in() {
1013   switch (tag()) {
1014   case DataLayout::no_tag:
1015   default:
1016     ShouldNotReachHere();
1017     return NULL;
1018   case DataLayout::bit_data_tag:
1019     return new BitData(this);
1020   case DataLayout::counter_data_tag:
1021     return new CounterData(this);
1022   case DataLayout::jump_data_tag:
1023     return new JumpData(this);
1024   case DataLayout::receiver_type_data_tag:
1025     return new ReceiverTypeData(this);
1026   case DataLayout::virtual_call_data_tag:
1027     return new VirtualCallData(this);
1028   case DataLayout::ret_data_tag:
1029     return new RetData(this);
1030   case DataLayout::branch_data_tag:
1031     return new BranchData(this);
1032   case DataLayout::multi_branch_data_tag:
1033     return new MultiBranchData(this);
1034   case DataLayout::arg_info_data_tag:
1035     return new ArgInfoData(this);
1036   case DataLayout::call_type_data_tag:
1037     return new CallTypeData(this);
1038   case DataLayout::virtual_call_type_data_tag:
1039     return new VirtualCallTypeData(this);
1040   case DataLayout::parameters_type_data_tag:
1041     return new ParametersTypeData(this);
1042   };
1043 }
1044 
1045 // Iteration over data.
1046 ProfileData* MethodData::next_data(ProfileData* current) const {
1047   int current_index = dp_to_di(current->dp());
1048   int next_index = current_index + current->size_in_bytes();
1049   ProfileData* next = data_at(next_index);
1050   return next;
1051 }
1052 
1053 // Give each of the data entries a chance to perform specific
1054 // data initialization.
1055 void MethodData::post_initialize(BytecodeStream* stream) {
1056   ResourceMark rm;
1057   ProfileData* data;
1058   for (data = first_data(); is_valid(data); data = next_data(data)) {
1059     stream->set_start(data->bci());
1060     stream->next();
1061     data->post_initialize(stream, this);
1062   }
1063   if (_parameters_type_data_di != -1) {
1064     parameters_type_data()->post_initialize(NULL, this);
1065   }
1066 }
1067 
1068 // Initialize the MethodData* corresponding to a given method.
1069 MethodData::MethodData(methodHandle method, int size, TRAPS)
1070   : _extra_data_lock(Monitor::leaf, "MDO extra data lock") {
1071   No_Safepoint_Verifier no_safepoint;  // init function atomic wrt GC
1072   ResourceMark rm;
1073   // Set the method back-pointer.
1074   _method = method();
1075 
1076   init();
1077   set_creation_mileage(mileage_of(method()));
1078 
1079   // Go through the bytecodes and allocate and initialize the
1080   // corresponding data cells.
1081   int data_size = 0;
1082   int empty_bc_count = 0;  // number of bytecodes lacking data
1083   _data[0] = 0;  // apparently not set below.
1084   BytecodeStream stream(method);
1085   Bytecodes::Code c;
1086   bool needs_speculative_traps = false;
1087   while ((c = stream.next()) >= 0) {
1088     int size_in_bytes = initialize_data(&stream, data_size);
1089     data_size += size_in_bytes;
1090     if (size_in_bytes == 0)  empty_bc_count += 1;
1091     needs_speculative_traps = needs_speculative_traps || is_speculative_trap_bytecode(c);
1092   }
1093   _data_size = data_size;
1094   int object_size = in_bytes(data_offset()) + data_size;
1095 
1096   // Add some extra DataLayout cells (at least one) to track stray traps.
1097   int extra_data_count = compute_extra_data_count(data_size, empty_bc_count, needs_speculative_traps);
1098   int extra_size = extra_data_count * DataLayout::compute_size_in_bytes(0);
1099 
1100   // Let's zero the space for the extra data
1101   Copy::zero_to_bytes(((address)_data) + data_size, extra_size);
1102 
1103   // Add a cell to record information about modified arguments.
1104   // Set up _args_modified array after traps cells so that
1105   // the code for traps cells works.
1106   DataLayout *dp = data_layout_at(data_size + extra_size);
1107 
1108   int arg_size = method->size_of_parameters();
1109   dp->initialize(DataLayout::arg_info_data_tag, 0, arg_size+1);
1110 
1111   int arg_data_size = DataLayout::compute_size_in_bytes(arg_size+1);
1112   object_size += extra_size + arg_data_size;
1113 
1114   int parms_cell = ParametersTypeData::compute_cell_count(method());
1115   // If we are profiling parameters, we reserver an area near the end
1116   // of the MDO after the slots for bytecodes (because there's no bci
1117   // for method entry so they don't fit with the framework for the
1118   // profiling of bytecodes). We store the offset within the MDO of
1119   // this area (or -1 if no parameter is profiled)
1120   if (parms_cell > 0) {
1121     object_size += DataLayout::compute_size_in_bytes(parms_cell);
1122     _parameters_type_data_di = data_size + extra_size + arg_data_size;
1123     DataLayout *dp = data_layout_at(data_size + extra_size + arg_data_size);
1124     dp->initialize(DataLayout::parameters_type_data_tag, 0, parms_cell);
1125   } else {
1126     _parameters_type_data_di = -1;
1127   }
1128 
1129   // Set an initial hint. Don't use set_hint_di() because
1130   // first_di() may be out of bounds if data_size is 0.
1131   // In that situation, _hint_di is never used, but at
1132   // least well-defined.
1133   _hint_di = first_di();
1134 
1135   post_initialize(&stream);
1136 
1137   set_size(object_size);
1138 }
1139 
1140 void MethodData::init() {
1141   _invocation_counter.init();
1142   _backedge_counter.init();
1143   _invocation_counter_start = 0;
1144   _backedge_counter_start = 0;
1145   _num_loops = 0;
1146   _num_blocks = 0;
1147   _highest_comp_level = 0;
1148   _highest_osr_comp_level = 0;
1149   _would_profile = true;
1150 
1151   // Initialize flags and trap history.
1152   _nof_decompiles = 0;
1153   _nof_overflow_recompiles = 0;
1154   _nof_overflow_traps = 0;
1155   clear_escape_info();
1156   assert(sizeof(_trap_hist) % sizeof(HeapWord) == 0, "align");
1157   Copy::zero_to_words((HeapWord*) &_trap_hist,
1158                       sizeof(_trap_hist) / sizeof(HeapWord));
1159 }
1160 
1161 // Get a measure of how much mileage the method has on it.
1162 int MethodData::mileage_of(Method* method) {
1163   int mileage = 0;
1164   if (TieredCompilation) {
1165     mileage = MAX2(method->invocation_count(), method->backedge_count());
1166   } else {
1167     int iic = method->interpreter_invocation_count();
1168     if (mileage < iic)  mileage = iic;
1169     MethodCounters* mcs = method->method_counters();
1170     if (mcs != NULL) {
1171       InvocationCounter* ic = mcs->invocation_counter();
1172       InvocationCounter* bc = mcs->backedge_counter();
1173       int icval = ic->count();
1174       if (ic->carry()) icval += CompileThreshold;
1175       if (mileage < icval)  mileage = icval;
1176       int bcval = bc->count();
1177       if (bc->carry()) bcval += CompileThreshold;
1178       if (mileage < bcval)  mileage = bcval;
1179     }
1180   }
1181   return mileage;
1182 }
1183 
1184 bool MethodData::is_mature() const {
1185   return CompilationPolicy::policy()->is_mature(_method);
1186 }
1187 
1188 // Translate a bci to its corresponding data index (di).
1189 address MethodData::bci_to_dp(int bci) {
1190   ResourceMark rm;
1191   ProfileData* data = data_before(bci);
1192   ProfileData* prev = NULL;
1193   for ( ; is_valid(data); data = next_data(data)) {
1194     if (data->bci() >= bci) {
1195       if (data->bci() == bci)  set_hint_di(dp_to_di(data->dp()));
1196       else if (prev != NULL)   set_hint_di(dp_to_di(prev->dp()));
1197       return data->dp();
1198     }
1199     prev = data;
1200   }
1201   return (address)limit_data_position();
1202 }
1203 
1204 // Translate a bci to its corresponding data, or NULL.
1205 ProfileData* MethodData::bci_to_data(int bci) {
1206   ProfileData* data = data_before(bci);
1207   for ( ; is_valid(data); data = next_data(data)) {
1208     if (data->bci() == bci) {
1209       set_hint_di(dp_to_di(data->dp()));
1210       return data;
1211     } else if (data->bci() > bci) {
1212       break;
1213     }
1214   }
1215   return bci_to_extra_data(bci, NULL, false);
1216 }
1217 
1218 DataLayout* MethodData::next_extra(DataLayout* dp) {
1219   int nb_cells = 0;
1220   switch(dp->tag()) {
1221   case DataLayout::bit_data_tag:
1222   case DataLayout::no_tag:
1223     nb_cells = BitData::static_cell_count();
1224     break;
1225   case DataLayout::speculative_trap_data_tag:
1226     nb_cells = SpeculativeTrapData::static_cell_count();
1227     break;
1228   default:
1229     fatal(err_msg("unexpected tag %d", dp->tag()));
1230   }
1231   return (DataLayout*)((address)dp + DataLayout::compute_size_in_bytes(nb_cells));
1232 }
1233 
1234 ProfileData* MethodData::bci_to_extra_data_helper(int bci, Method* m, DataLayout*& dp, bool concurrent) {
1235   DataLayout* end = extra_data_limit();
1236 
1237   for (;; dp = next_extra(dp)) {
1238     assert(dp < end, "moved past end of extra data");
1239     // No need for "OrderAccess::load_acquire" ops,
1240     // since the data structure is monotonic.
1241     switch(dp->tag()) {
1242     case DataLayout::no_tag:
1243       return NULL;
1244     case DataLayout::arg_info_data_tag:
1245       dp = end;
1246       return NULL; // ArgInfoData is at the end of extra data section.
1247     case DataLayout::bit_data_tag:
1248       if (m == NULL && dp->bci() == bci) {
1249         return new BitData(dp);
1250       }
1251       break;
1252     case DataLayout::speculative_trap_data_tag:
1253       if (m != NULL) {
1254         SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1255         // data->method() may be null in case of a concurrent
1256         // allocation. Maybe it's for the same method. Try to use that
1257         // entry in that case.
1258         if (dp->bci() == bci) {
1259           if (data->method() == NULL) {
1260             assert(concurrent, "impossible because no concurrent allocation");
1261             return NULL;
1262           } else if (data->method() == m) {
1263             return data;
1264           }
1265         }
1266       }
1267       break;
1268     default:
1269       fatal(err_msg("unexpected tag %d", dp->tag()));
1270     }
1271   }
1272   return NULL;
1273 }
1274 
1275 
1276 // Translate a bci to its corresponding extra data, or NULL.
1277 ProfileData* MethodData::bci_to_extra_data(int bci, Method* m, bool create_if_missing) {
1278   // This code assumes an entry for a SpeculativeTrapData is 2 cells
1279   assert(2*DataLayout::compute_size_in_bytes(BitData::static_cell_count()) ==
1280          DataLayout::compute_size_in_bytes(SpeculativeTrapData::static_cell_count()),
1281          "code needs to be adjusted");
1282 
1283   DataLayout* dp  = extra_data_base();
1284   DataLayout* end = extra_data_limit();
1285 
1286   // Allocation in the extra data space has to be atomic because not
1287   // all entries have the same size and non atomic concurrent
1288   // allocation would result in a corrupted extra data space.
1289   ProfileData* result = bci_to_extra_data_helper(bci, m, dp, true);
1290   if (result != NULL) {
1291     return result;
1292   }
1293 
1294   if (create_if_missing && dp < end) {
1295     MutexLocker ml(&_extra_data_lock);
1296     // Check again now that we have the lock. Another thread may
1297     // have added extra data entries.
1298     ProfileData* result = bci_to_extra_data_helper(bci, m, dp, false);
1299     if (result != NULL || dp >= end) {
1300       return result;
1301     }
1302 
1303     assert(dp->tag() == DataLayout::no_tag || (dp->tag() == DataLayout::speculative_trap_data_tag && m != NULL), "should be free");
1304     assert(next_extra(dp)->tag() == DataLayout::no_tag || next_extra(dp)->tag() == DataLayout::arg_info_data_tag, "should be free or arg info");
1305     u1 tag = m == NULL ? DataLayout::bit_data_tag : DataLayout::speculative_trap_data_tag;
1306     // SpeculativeTrapData is 2 slots. Make sure we have room.
1307     if (m != NULL && next_extra(dp)->tag() != DataLayout::no_tag) {
1308       return NULL;
1309     }
1310     DataLayout temp;
1311     temp.initialize(tag, bci, 0);
1312 
1313     dp->set_header(temp.header());
1314     assert(dp->tag() == tag, "sane");
1315     assert(dp->bci() == bci, "no concurrent allocation");
1316     if (tag == DataLayout::bit_data_tag) {
1317       return new BitData(dp);
1318     } else {
1319       SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1320       data->set_method(m);
1321       return data;
1322     }
1323   }
1324   return NULL;
1325 }
1326 
1327 ArgInfoData *MethodData::arg_info() {
1328   DataLayout* dp    = extra_data_base();
1329   DataLayout* end   = extra_data_limit();
1330   for (; dp < end; dp = next_extra(dp)) {
1331     if (dp->tag() == DataLayout::arg_info_data_tag)
1332       return new ArgInfoData(dp);
1333   }
1334   return NULL;
1335 }
1336 
1337 // Printing
1338 
1339 #ifndef PRODUCT
1340 
1341 void MethodData::print_on(outputStream* st) const {
1342   assert(is_methodData(), "should be method data");
1343   st->print("method data for ");
1344   method()->print_value_on(st);
1345   st->cr();
1346   print_data_on(st);
1347 }
1348 
1349 #endif //PRODUCT
1350 
1351 void MethodData::print_value_on(outputStream* st) const {
1352   assert(is_methodData(), "should be method data");
1353   st->print("method data for ");
1354   method()->print_value_on(st);
1355 }
1356 
1357 #ifndef PRODUCT
1358 void MethodData::print_data_on(outputStream* st) const {
1359   ResourceMark rm;
1360   ProfileData* data = first_data();
1361   if (_parameters_type_data_di != -1) {
1362     parameters_type_data()->print_data_on(st);
1363   }
1364   for ( ; is_valid(data); data = next_data(data)) {
1365     st->print("%d", dp_to_di(data->dp()));
1366     st->fill_to(6);
1367     data->print_data_on(st, this);
1368   }
1369   st->print_cr("--- Extra data:");
1370   DataLayout* dp    = extra_data_base();
1371   DataLayout* end   = extra_data_limit();
1372   for (;; dp = next_extra(dp)) {
1373     assert(dp < end, "moved past end of extra data");
1374     // No need for "OrderAccess::load_acquire" ops,
1375     // since the data structure is monotonic.
1376     switch(dp->tag()) {
1377     case DataLayout::no_tag:
1378       continue;
1379     case DataLayout::bit_data_tag:
1380       data = new BitData(dp);
1381       break;
1382     case DataLayout::speculative_trap_data_tag:
1383       data = new SpeculativeTrapData(dp);
1384       break;
1385     case DataLayout::arg_info_data_tag:
1386       data = new ArgInfoData(dp);
1387       dp = end; // ArgInfoData is at the end of extra data section.
1388       break;
1389     default:
1390       fatal(err_msg("unexpected tag %d", dp->tag()));
1391     }
1392     st->print("%d", dp_to_di(data->dp()));
1393     st->fill_to(6);
1394     data->print_data_on(st);
1395     if (dp >= end) return;
1396   }
1397 }
1398 #endif
1399 
1400 #if INCLUDE_SERVICES
1401 // Size Statistics
1402 void MethodData::collect_statistics(KlassSizeStats *sz) const {
1403   int n = sz->count(this);
1404   sz->_method_data_bytes += n;
1405   sz->_method_all_bytes += n;
1406   sz->_rw_bytes += n;
1407 }
1408 #endif // INCLUDE_SERVICES
1409 
1410 // Verification
1411 
1412 void MethodData::verify_on(outputStream* st) {
1413   guarantee(is_methodData(), "object must be method data");
1414   // guarantee(m->is_perm(), "should be in permspace");
1415   this->verify_data_on(st);
1416 }
1417 
1418 void MethodData::verify_data_on(outputStream* st) {
1419   NEEDS_CLEANUP;
1420   // not yet implemented.
1421 }
1422 
1423 bool MethodData::profile_jsr292(methodHandle m, int bci) {
1424   if (m->is_compiled_lambda_form()) {
1425     return true;
1426   }
1427 
1428   Bytecode_invoke inv(m , bci);
1429   return inv.is_invokedynamic() || inv.is_invokehandle();
1430 }
1431 
1432 int MethodData::profile_arguments_flag() {
1433   return TypeProfileLevel % 10;
1434 }
1435 
1436 bool MethodData::profile_arguments() {
1437   return profile_arguments_flag() > no_type_profile && profile_arguments_flag() <= type_profile_all;
1438 }
1439 
1440 bool MethodData::profile_arguments_jsr292_only() {
1441   return profile_arguments_flag() == type_profile_jsr292;
1442 }
1443 
1444 bool MethodData::profile_all_arguments() {
1445   return profile_arguments_flag() == type_profile_all;
1446 }
1447 
1448 bool MethodData::profile_arguments_for_invoke(methodHandle m, int bci) {
1449   if (!profile_arguments()) {
1450     return false;
1451   }
1452 
1453   if (profile_all_arguments()) {
1454     return true;
1455   }
1456 
1457   assert(profile_arguments_jsr292_only(), "inconsistent");
1458   return profile_jsr292(m, bci);
1459 }
1460 
1461 int MethodData::profile_return_flag() {
1462   return (TypeProfileLevel % 100) / 10;
1463 }
1464 
1465 bool MethodData::profile_return() {
1466   return profile_return_flag() > no_type_profile && profile_return_flag() <= type_profile_all;
1467 }
1468 
1469 bool MethodData::profile_return_jsr292_only() {
1470   return profile_return_flag() == type_profile_jsr292;
1471 }
1472 
1473 bool MethodData::profile_all_return() {
1474   return profile_return_flag() == type_profile_all;
1475 }
1476 
1477 bool MethodData::profile_return_for_invoke(methodHandle m, int bci) {
1478   if (!profile_return()) {
1479     return false;
1480   }
1481 
1482   if (profile_all_return()) {
1483     return true;
1484   }
1485 
1486   assert(profile_return_jsr292_only(), "inconsistent");
1487   return profile_jsr292(m, bci);
1488 }
1489 
1490 int MethodData::profile_parameters_flag() {
1491   return TypeProfileLevel / 100;
1492 }
1493 
1494 bool MethodData::profile_parameters() {
1495   return profile_parameters_flag() > no_type_profile && profile_parameters_flag() <= type_profile_all;
1496 }
1497 
1498 bool MethodData::profile_parameters_jsr292_only() {
1499   return profile_parameters_flag() == type_profile_jsr292;
1500 }
1501 
1502 bool MethodData::profile_all_parameters() {
1503   return profile_parameters_flag() == type_profile_all;
1504 }
1505 
1506 bool MethodData::profile_parameters_for_method(methodHandle m) {
1507   if (!profile_parameters()) {
1508     return false;
1509   }
1510 
1511   if (profile_all_parameters()) {
1512     return true;
1513   }
1514 
1515   assert(profile_parameters_jsr292_only(), "inconsistent");
1516   return m->is_compiled_lambda_form();
1517 }
1518 
1519 void MethodData::clean_extra_data_helper(DataLayout* dp, int shift, bool reset) {
1520   if (shift == 0) {
1521     return;
1522   }
1523   if (!reset) {
1524     // Move all cells of trap entry at dp left by "shift" cells
1525     intptr_t* start = (intptr_t*)dp;
1526     intptr_t* end = (intptr_t*)next_extra(dp);
1527     for (intptr_t* ptr = start; ptr < end; ptr++) {
1528       *(ptr-shift) = *ptr;
1529     }
1530   } else {
1531     // Reset "shift" cells stopping at dp
1532     intptr_t* start = ((intptr_t*)dp) - shift;
1533     intptr_t* end = (intptr_t*)dp;
1534     for (intptr_t* ptr = start; ptr < end; ptr++) {
1535       *ptr = 0;
1536     }
1537   }
1538 }
1539 
1540 // Remove SpeculativeTrapData entries that reference an unloaded
1541 // method
1542 void MethodData::clean_extra_data(BoolObjectClosure* is_alive) {
1543   DataLayout* dp  = extra_data_base();
1544   DataLayout* end = extra_data_limit();
1545 
1546   int shift = 0;
1547   for (; dp < end; dp = next_extra(dp)) {
1548     switch(dp->tag()) {
1549     case DataLayout::speculative_trap_data_tag: {
1550       SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1551       Method* m = data->method();
1552       assert(m != NULL, "should have a method");
1553       if (!m->method_holder()->is_loader_alive(is_alive)) {
1554         // "shift" accumulates the number of cells for dead
1555         // SpeculativeTrapData entries that have been seen so
1556         // far. Following entries must be shifted left by that many
1557         // cells to remove the dead SpeculativeTrapData entries.
1558         shift += (int)((intptr_t*)next_extra(dp) - (intptr_t*)dp);
1559       } else {
1560         // Shift this entry left if it follows dead
1561         // SpeculativeTrapData entries
1562         clean_extra_data_helper(dp, shift);
1563       }
1564       break;
1565     }
1566     case DataLayout::bit_data_tag:
1567       // Shift this entry left if it follows dead SpeculativeTrapData
1568       // entries
1569       clean_extra_data_helper(dp, shift);
1570       continue;
1571     case DataLayout::no_tag:
1572     case DataLayout::arg_info_data_tag:
1573       // We are at end of the live trap entries. The previous "shift"
1574       // cells contain entries that are either dead or were shifted
1575       // left. They need to be reset to no_tag
1576       clean_extra_data_helper(dp, shift, true);
1577       return;
1578     default:
1579       fatal(err_msg("unexpected tag %d", dp->tag()));
1580     }
1581   }
1582 }
1583 
1584 // Verify there's no unloaded method referenced by a
1585 // SpeculativeTrapData entry
1586 void MethodData::verify_extra_data_clean(BoolObjectClosure* is_alive) {
1587 #ifdef ASSERT
1588   DataLayout* dp  = extra_data_base();
1589   DataLayout* end = extra_data_limit();
1590 
1591   for (; dp < end; dp = next_extra(dp)) {
1592     switch(dp->tag()) {
1593     case DataLayout::speculative_trap_data_tag: {
1594       SpeculativeTrapData* data = new SpeculativeTrapData(dp);
1595       Method* m = data->method();
1596       assert(m != NULL && m->method_holder()->is_loader_alive(is_alive), "Method should exist");
1597       break;
1598     }
1599     case DataLayout::bit_data_tag:
1600       continue;
1601     case DataLayout::no_tag:
1602     case DataLayout::arg_info_data_tag:
1603       return;
1604     default:
1605       fatal(err_msg("unexpected tag %d", dp->tag()));
1606     }
1607   }
1608 #endif
1609 }
1610 
1611 void MethodData::clean_method_data(BoolObjectClosure* is_alive) {
1612   for (ProfileData* data = first_data();
1613        is_valid(data);
1614        data = next_data(data)) {
1615     data->clean_weak_klass_links(is_alive);
1616   }
1617   ParametersTypeData* parameters = parameters_type_data();
1618   if (parameters != NULL) {
1619     parameters->clean_weak_klass_links(is_alive);
1620   }
1621 
1622   clean_extra_data(is_alive);
1623   verify_extra_data_clean(is_alive);
1624 }