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
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  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
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  24 
  25 #ifndef SHARE_VM_OOPS_METHODDATAOOP_HPP
  26 #define SHARE_VM_OOPS_METHODDATAOOP_HPP
  27 
  28 #include "interpreter/bytecodes.hpp"
  29 #include "memory/universe.hpp"
  30 #include "oops/method.hpp"
  31 #include "oops/oop.hpp"
  32 #include "runtime/orderAccess.hpp"
  33 
  34 class BytecodeStream;
  35 class KlassSizeStats;
  36 
  37 // The MethodData object collects counts and other profile information
  38 // during zeroth-tier (interpretive) and first-tier execution.
  39 // The profile is used later by compilation heuristics.  Some heuristics
  40 // enable use of aggressive (or "heroic") optimizations.  An aggressive
  41 // optimization often has a down-side, a corner case that it handles
  42 // poorly, but which is thought to be rare.  The profile provides
  43 // evidence of this rarity for a given method or even BCI.  It allows
  44 // the compiler to back out of the optimization at places where it
  45 // has historically been a poor choice.  Other heuristics try to use
  46 // specific information gathered about types observed at a given site.
  47 //
  48 // All data in the profile is approximate.  It is expected to be accurate
  49 // on the whole, but the system expects occasional inaccuraces, due to
  50 // counter overflow, multiprocessor races during data collection, space
  51 // limitations, missing MDO blocks, etc.  Bad or missing data will degrade
  52 // optimization quality but will not affect correctness.  Also, each MDO
  53 // is marked with its birth-date ("creation_mileage") which can be used
  54 // to assess the quality ("maturity") of its data.
  55 //
  56 // Short (<32-bit) counters are designed to overflow to a known "saturated"
  57 // state.  Also, certain recorded per-BCI events are given one-bit counters
  58 // which overflow to a saturated state which applied to all counters at
  59 // that BCI.  In other words, there is a small lattice which approximates
  60 // the ideal of an infinite-precision counter for each event at each BCI,
  61 // and the lattice quickly "bottoms out" in a state where all counters
  62 // are taken to be indefinitely large.
  63 //
  64 // The reader will find many data races in profile gathering code, starting
  65 // with invocation counter incrementation.  None of these races harm correct
  66 // execution of the compiled code.
  67 
  68 // forward decl
  69 class ProfileData;
  70 
  71 // DataLayout
  72 //
  73 // Overlay for generic profiling data.
  74 class DataLayout VALUE_OBJ_CLASS_SPEC {
  75   friend class VMStructs;
  76 
  77 private:
  78   // Every data layout begins with a header.  This header
  79   // contains a tag, which is used to indicate the size/layout
  80   // of the data, 4 bits of flags, which can be used in any way,
  81   // 4 bits of trap history (none/one reason/many reasons),
  82   // and a bci, which is used to tie this piece of data to a
  83   // specific bci in the bytecodes.
  84   union {
  85     intptr_t _bits;
  86     struct {
  87       u1 _tag;
  88       u1 _flags;
  89       u2 _bci;
  90     } _struct;
  91   } _header;
  92 
  93   // The data layout has an arbitrary number of cells, each sized
  94   // to accomodate a pointer or an integer.
  95   intptr_t _cells[1];
  96 
  97   // Some types of data layouts need a length field.
  98   static bool needs_array_len(u1 tag);
  99 
 100 public:
 101   enum {
 102     counter_increment = 1
 103   };
 104 
 105   enum {
 106     cell_size = sizeof(intptr_t)
 107   };
 108 
 109   // Tag values
 110   enum {
 111     no_tag,
 112     bit_data_tag,
 113     counter_data_tag,
 114     jump_data_tag,
 115     receiver_type_data_tag,
 116     virtual_call_data_tag,
 117     ret_data_tag,
 118     branch_data_tag,
 119     multi_branch_data_tag,
 120     arg_info_data_tag,
 121     call_type_data_tag,
 122     virtual_call_type_data_tag,
 123     parameters_type_data_tag
 124   };
 125 
 126   enum {
 127     // The _struct._flags word is formatted as [trap_state:4 | flags:4].
 128     // The trap state breaks down further as [recompile:1 | reason:3].
 129     // This further breakdown is defined in deoptimization.cpp.
 130     // See Deoptimization::trap_state_reason for an assert that
 131     // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
 132     //
 133     // The trap_state is collected only if ProfileTraps is true.
 134     trap_bits = 1+3,  // 3: enough to distinguish [0..Reason_RECORDED_LIMIT].
 135     trap_shift = BitsPerByte - trap_bits,
 136     trap_mask = right_n_bits(trap_bits),
 137     trap_mask_in_place = (trap_mask << trap_shift),
 138     flag_limit = trap_shift,
 139     flag_mask = right_n_bits(flag_limit),
 140     first_flag = 0
 141   };
 142 
 143   // Size computation
 144   static int header_size_in_bytes() {
 145     return cell_size;
 146   }
 147   static int header_size_in_cells() {
 148     return 1;
 149   }
 150 
 151   static int compute_size_in_bytes(int cell_count) {
 152     return header_size_in_bytes() + cell_count * cell_size;
 153   }
 154 
 155   // Initialization
 156   void initialize(u1 tag, u2 bci, int cell_count);
 157 
 158   // Accessors
 159   u1 tag() {
 160     return _header._struct._tag;
 161   }
 162 
 163   // Return a few bits of trap state.  Range is [0..trap_mask].
 164   // The state tells if traps with zero, one, or many reasons have occurred.
 165   // It also tells whether zero or many recompilations have occurred.
 166   // The associated trap histogram in the MDO itself tells whether
 167   // traps are common or not.  If a BCI shows that a trap X has
 168   // occurred, and the MDO shows N occurrences of X, we make the
 169   // simplifying assumption that all N occurrences can be blamed
 170   // on that BCI.
 171   int trap_state() const {
 172     return ((_header._struct._flags >> trap_shift) & trap_mask);
 173   }
 174 
 175   void set_trap_state(int new_state) {
 176     assert(ProfileTraps, "used only under +ProfileTraps");
 177     uint old_flags = (_header._struct._flags & flag_mask);
 178     _header._struct._flags = (new_state << trap_shift) | old_flags;
 179   }
 180 
 181   u1 flags() const {
 182     return _header._struct._flags;
 183   }
 184 
 185   u2 bci() const {
 186     return _header._struct._bci;
 187   }
 188 
 189   void set_header(intptr_t value) {
 190     _header._bits = value;
 191   }
 192   void release_set_header(intptr_t value) {
 193     OrderAccess::release_store_ptr(&_header._bits, value);
 194   }
 195   intptr_t header() {
 196     return _header._bits;
 197   }
 198   void set_cell_at(int index, intptr_t value) {
 199     _cells[index] = value;
 200   }
 201   void release_set_cell_at(int index, intptr_t value) {
 202     OrderAccess::release_store_ptr(&_cells[index], value);
 203   }
 204   intptr_t cell_at(int index) const {
 205     return _cells[index];
 206   }
 207 
 208   void set_flag_at(int flag_number) {
 209     assert(flag_number < flag_limit, "oob");
 210     _header._struct._flags |= (0x1 << flag_number);
 211   }
 212   bool flag_at(int flag_number) const {
 213     assert(flag_number < flag_limit, "oob");
 214     return (_header._struct._flags & (0x1 << flag_number)) != 0;
 215   }
 216 
 217   // Low-level support for code generation.
 218   static ByteSize header_offset() {
 219     return byte_offset_of(DataLayout, _header);
 220   }
 221   static ByteSize tag_offset() {
 222     return byte_offset_of(DataLayout, _header._struct._tag);
 223   }
 224   static ByteSize flags_offset() {
 225     return byte_offset_of(DataLayout, _header._struct._flags);
 226   }
 227   static ByteSize bci_offset() {
 228     return byte_offset_of(DataLayout, _header._struct._bci);
 229   }
 230   static ByteSize cell_offset(int index) {
 231     return byte_offset_of(DataLayout, _cells) + in_ByteSize(index * cell_size);
 232   }
 233   // Return a value which, when or-ed as a byte into _flags, sets the flag.
 234   static int flag_number_to_byte_constant(int flag_number) {
 235     assert(0 <= flag_number && flag_number < flag_limit, "oob");
 236     DataLayout temp; temp.set_header(0);
 237     temp.set_flag_at(flag_number);
 238     return temp._header._struct._flags;
 239   }
 240   // Return a value which, when or-ed as a word into _header, sets the flag.
 241   static intptr_t flag_mask_to_header_mask(int byte_constant) {
 242     DataLayout temp; temp.set_header(0);
 243     temp._header._struct._flags = byte_constant;
 244     return temp._header._bits;
 245   }
 246 
 247   ProfileData* data_in();
 248 
 249   // GC support
 250   void clean_weak_klass_links(BoolObjectClosure* cl);
 251 };
 252 
 253 
 254 // ProfileData class hierarchy
 255 class ProfileData;
 256 class   BitData;
 257 class     CounterData;
 258 class       ReceiverTypeData;
 259 class         VirtualCallData;
 260 class           VirtualCallTypeData;
 261 class       RetData;
 262 class       CallTypeData;
 263 class   JumpData;
 264 class     BranchData;
 265 class   ArrayData;
 266 class     MultiBranchData;
 267 class     ArgInfoData;
 268 class     ParametersTypeData;
 269 
 270 // ProfileData
 271 //
 272 // A ProfileData object is created to refer to a section of profiling
 273 // data in a structured way.
 274 class ProfileData : public ResourceObj {
 275   friend class TypeEntries;
 276   friend class ReturnTypeEntry;
 277   friend class TypeStackSlotEntries;
 278 private:
 279 #ifndef PRODUCT
 280   enum {
 281     tab_width_one = 16,
 282     tab_width_two = 36
 283   };
 284 #endif // !PRODUCT
 285 
 286   // This is a pointer to a section of profiling data.
 287   DataLayout* _data;
 288 
 289 protected:
 290   DataLayout* data() { return _data; }
 291   const DataLayout* data() const { return _data; }
 292 
 293   enum {
 294     cell_size = DataLayout::cell_size
 295   };
 296 
 297 public:
 298   // How many cells are in this?
 299   virtual int cell_count() const {
 300     ShouldNotReachHere();
 301     return -1;
 302   }
 303 
 304   // Return the size of this data.
 305   int size_in_bytes() {
 306     return DataLayout::compute_size_in_bytes(cell_count());
 307   }
 308 
 309 protected:
 310   // Low-level accessors for underlying data
 311   void set_intptr_at(int index, intptr_t value) {
 312     assert(0 <= index && index < cell_count(), "oob");
 313     data()->set_cell_at(index, value);
 314   }
 315   void release_set_intptr_at(int index, intptr_t value) {
 316     assert(0 <= index && index < cell_count(), "oob");
 317     data()->release_set_cell_at(index, value);
 318   }
 319   intptr_t intptr_at(int index) const {
 320     assert(0 <= index && index < cell_count(), "oob");
 321     return data()->cell_at(index);
 322   }
 323   void set_uint_at(int index, uint value) {
 324     set_intptr_at(index, (intptr_t) value);
 325   }
 326   void release_set_uint_at(int index, uint value) {
 327     release_set_intptr_at(index, (intptr_t) value);
 328   }
 329   uint uint_at(int index) const {
 330     return (uint)intptr_at(index);
 331   }
 332   void set_int_at(int index, int value) {
 333     set_intptr_at(index, (intptr_t) value);
 334   }
 335   void release_set_int_at(int index, int value) {
 336     release_set_intptr_at(index, (intptr_t) value);
 337   }
 338   int int_at(int index) const {
 339     return (int)intptr_at(index);
 340   }
 341   int int_at_unchecked(int index) const {
 342     return (int)data()->cell_at(index);
 343   }
 344   void set_oop_at(int index, oop value) {
 345     set_intptr_at(index, cast_from_oop<intptr_t>(value));
 346   }
 347   oop oop_at(int index) const {
 348     return cast_to_oop(intptr_at(index));
 349   }
 350 
 351   void set_flag_at(int flag_number) {
 352     data()->set_flag_at(flag_number);
 353   }
 354   bool flag_at(int flag_number) const {
 355     return data()->flag_at(flag_number);
 356   }
 357 
 358   // two convenient imports for use by subclasses:
 359   static ByteSize cell_offset(int index) {
 360     return DataLayout::cell_offset(index);
 361   }
 362   static int flag_number_to_byte_constant(int flag_number) {
 363     return DataLayout::flag_number_to_byte_constant(flag_number);
 364   }
 365 
 366   ProfileData(DataLayout* data) {
 367     _data = data;
 368   }
 369 
 370 public:
 371   // Constructor for invalid ProfileData.
 372   ProfileData();
 373 
 374   u2 bci() const {
 375     return data()->bci();
 376   }
 377 
 378   address dp() {
 379     return (address)_data;
 380   }
 381 
 382   int trap_state() const {
 383     return data()->trap_state();
 384   }
 385   void set_trap_state(int new_state) {
 386     data()->set_trap_state(new_state);
 387   }
 388 
 389   // Type checking
 390   virtual bool is_BitData()         const { return false; }
 391   virtual bool is_CounterData()     const { return false; }
 392   virtual bool is_JumpData()        const { return false; }
 393   virtual bool is_ReceiverTypeData()const { return false; }
 394   virtual bool is_VirtualCallData() const { return false; }
 395   virtual bool is_RetData()         const { return false; }
 396   virtual bool is_BranchData()      const { return false; }
 397   virtual bool is_ArrayData()       const { return false; }
 398   virtual bool is_MultiBranchData() const { return false; }
 399   virtual bool is_ArgInfoData()     const { return false; }
 400   virtual bool is_CallTypeData()    const { return false; }
 401   virtual bool is_VirtualCallTypeData()const { return false; }
 402   virtual bool is_ParametersTypeData() const { return false; }
 403 
 404 
 405   BitData* as_BitData() const {
 406     assert(is_BitData(), "wrong type");
 407     return is_BitData()         ? (BitData*)        this : NULL;
 408   }
 409   CounterData* as_CounterData() const {
 410     assert(is_CounterData(), "wrong type");
 411     return is_CounterData()     ? (CounterData*)    this : NULL;
 412   }
 413   JumpData* as_JumpData() const {
 414     assert(is_JumpData(), "wrong type");
 415     return is_JumpData()        ? (JumpData*)       this : NULL;
 416   }
 417   ReceiverTypeData* as_ReceiverTypeData() const {
 418     assert(is_ReceiverTypeData(), "wrong type");
 419     return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
 420   }
 421   VirtualCallData* as_VirtualCallData() const {
 422     assert(is_VirtualCallData(), "wrong type");
 423     return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
 424   }
 425   RetData* as_RetData() const {
 426     assert(is_RetData(), "wrong type");
 427     return is_RetData()         ? (RetData*)        this : NULL;
 428   }
 429   BranchData* as_BranchData() const {
 430     assert(is_BranchData(), "wrong type");
 431     return is_BranchData()      ? (BranchData*)     this : NULL;
 432   }
 433   ArrayData* as_ArrayData() const {
 434     assert(is_ArrayData(), "wrong type");
 435     return is_ArrayData()       ? (ArrayData*)      this : NULL;
 436   }
 437   MultiBranchData* as_MultiBranchData() const {
 438     assert(is_MultiBranchData(), "wrong type");
 439     return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
 440   }
 441   ArgInfoData* as_ArgInfoData() const {
 442     assert(is_ArgInfoData(), "wrong type");
 443     return is_ArgInfoData() ? (ArgInfoData*)this : NULL;
 444   }
 445   CallTypeData* as_CallTypeData() const {
 446     assert(is_CallTypeData(), "wrong type");
 447     return is_CallTypeData() ? (CallTypeData*)this : NULL;
 448   }
 449   VirtualCallTypeData* as_VirtualCallTypeData() const {
 450     assert(is_VirtualCallTypeData(), "wrong type");
 451     return is_VirtualCallTypeData() ? (VirtualCallTypeData*)this : NULL;
 452   }
 453   ParametersTypeData* as_ParametersTypeData() const {
 454     assert(is_ParametersTypeData(), "wrong type");
 455     return is_ParametersTypeData() ? (ParametersTypeData*)this : NULL;
 456   }
 457 
 458 
 459   // Subclass specific initialization
 460   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo) {}
 461 
 462   // GC support
 463   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {}
 464 
 465   // CI translation: ProfileData can represent both MethodDataOop data
 466   // as well as CIMethodData data. This function is provided for translating
 467   // an oop in a ProfileData to the ci equivalent. Generally speaking,
 468   // most ProfileData don't require any translation, so we provide the null
 469   // translation here, and the required translators are in the ci subclasses.
 470   virtual void translate_from(const ProfileData* data) {}
 471 
 472   virtual void print_data_on(outputStream* st) const {
 473     ShouldNotReachHere();
 474   }
 475 
 476 #ifndef PRODUCT
 477   void print_shared(outputStream* st, const char* name) const;
 478   void tab(outputStream* st, bool first = false) const;
 479 #endif
 480 };
 481 
 482 // BitData
 483 //
 484 // A BitData holds a flag or two in its header.
 485 class BitData : public ProfileData {
 486 protected:
 487   enum {
 488     // null_seen:
 489     //  saw a null operand (cast/aastore/instanceof)
 490     null_seen_flag              = DataLayout::first_flag + 0
 491   };
 492   enum { bit_cell_count = 0 };  // no additional data fields needed.
 493 public:
 494   BitData(DataLayout* layout) : ProfileData(layout) {
 495   }
 496 
 497   virtual bool is_BitData() const { return true; }
 498 
 499   static int static_cell_count() {
 500     return bit_cell_count;
 501   }
 502 
 503   virtual int cell_count() const {
 504     return static_cell_count();
 505   }
 506 
 507   // Accessor
 508 
 509   // The null_seen flag bit is specially known to the interpreter.
 510   // Consulting it allows the compiler to avoid setting up null_check traps.
 511   bool null_seen()     { return flag_at(null_seen_flag); }
 512   void set_null_seen()    { set_flag_at(null_seen_flag); }
 513 
 514 
 515   // Code generation support
 516   static int null_seen_byte_constant() {
 517     return flag_number_to_byte_constant(null_seen_flag);
 518   }
 519 
 520   static ByteSize bit_data_size() {
 521     return cell_offset(bit_cell_count);
 522   }
 523 
 524 #ifndef PRODUCT
 525   void print_data_on(outputStream* st) const;
 526 #endif
 527 };
 528 
 529 // CounterData
 530 //
 531 // A CounterData corresponds to a simple counter.
 532 class CounterData : public BitData {
 533 protected:
 534   enum {
 535     count_off,
 536     counter_cell_count
 537   };
 538 public:
 539   CounterData(DataLayout* layout) : BitData(layout) {}
 540 
 541   virtual bool is_CounterData() const { return true; }
 542 
 543   static int static_cell_count() {
 544     return counter_cell_count;
 545   }
 546 
 547   virtual int cell_count() const {
 548     return static_cell_count();
 549   }
 550 
 551   // Direct accessor
 552   uint count() const {
 553     return uint_at(count_off);
 554   }
 555 
 556   // Code generation support
 557   static ByteSize count_offset() {
 558     return cell_offset(count_off);
 559   }
 560   static ByteSize counter_data_size() {
 561     return cell_offset(counter_cell_count);
 562   }
 563 
 564   void set_count(uint count) {
 565     set_uint_at(count_off, count);
 566   }
 567 
 568 #ifndef PRODUCT
 569   void print_data_on(outputStream* st) const;
 570 #endif
 571 };
 572 
 573 // JumpData
 574 //
 575 // A JumpData is used to access profiling information for a direct
 576 // branch.  It is a counter, used for counting the number of branches,
 577 // plus a data displacement, used for realigning the data pointer to
 578 // the corresponding target bci.
 579 class JumpData : public ProfileData {
 580 protected:
 581   enum {
 582     taken_off_set,
 583     displacement_off_set,
 584     jump_cell_count
 585   };
 586 
 587   void set_displacement(int displacement) {
 588     set_int_at(displacement_off_set, displacement);
 589   }
 590 
 591 public:
 592   JumpData(DataLayout* layout) : ProfileData(layout) {
 593     assert(layout->tag() == DataLayout::jump_data_tag ||
 594       layout->tag() == DataLayout::branch_data_tag, "wrong type");
 595   }
 596 
 597   virtual bool is_JumpData() const { return true; }
 598 
 599   static int static_cell_count() {
 600     return jump_cell_count;
 601   }
 602 
 603   virtual int cell_count() const {
 604     return static_cell_count();
 605   }
 606 
 607   // Direct accessor
 608   uint taken() const {
 609     return uint_at(taken_off_set);
 610   }
 611 
 612   void set_taken(uint cnt) {
 613     set_uint_at(taken_off_set, cnt);
 614   }
 615 
 616   // Saturating counter
 617   uint inc_taken() {
 618     uint cnt = taken() + 1;
 619     // Did we wrap? Will compiler screw us??
 620     if (cnt == 0) cnt--;
 621     set_uint_at(taken_off_set, cnt);
 622     return cnt;
 623   }
 624 
 625   int displacement() const {
 626     return int_at(displacement_off_set);
 627   }
 628 
 629   // Code generation support
 630   static ByteSize taken_offset() {
 631     return cell_offset(taken_off_set);
 632   }
 633 
 634   static ByteSize displacement_offset() {
 635     return cell_offset(displacement_off_set);
 636   }
 637 
 638   // Specific initialization.
 639   void post_initialize(BytecodeStream* stream, MethodData* mdo);
 640 
 641 #ifndef PRODUCT
 642   void print_data_on(outputStream* st) const;
 643 #endif
 644 };
 645 
 646 // Entries in a ProfileData object to record types: it can either be
 647 // none (no profile), unknown (conflicting profile data) or a klass if
 648 // a single one is seen. Whether a null reference was seen is also
 649 // recorded. No counter is associated with the type and a single type
 650 // is tracked (unlike VirtualCallData).
 651 class TypeEntries {
 652 
 653 public:
 654 
 655   // A single cell is used to record information for a type:
 656   // - the cell is initialized to 0
 657   // - when a type is discovered it is stored in the cell
 658   // - bit zero of the cell is used to record whether a null reference
 659   // was encountered or not
 660   // - bit 1 is set to record a conflict in the type information
 661 
 662   enum {
 663     null_seen = 1,
 664     type_mask = ~null_seen,
 665     type_unknown = 2,
 666     status_bits = null_seen | type_unknown,
 667     type_klass_mask = ~status_bits
 668   };
 669 
 670   // what to initialize a cell to
 671   static intptr_t type_none() {
 672     return 0;
 673   }
 674 
 675   // null seen = bit 0 set?
 676   static bool was_null_seen(intptr_t v) {
 677     return (v & null_seen) != 0;
 678   }
 679 
 680   // conflicting type information = bit 1 set?
 681   static bool is_type_unknown(intptr_t v) {
 682     return (v & type_unknown) != 0;
 683   }
 684 
 685   // not type information yet = all bits cleared, ignoring bit 0?
 686   static bool is_type_none(intptr_t v) {
 687     return (v & type_mask) == 0;
 688   }
 689 
 690   // recorded type: cell without bit 0 and 1
 691   static intptr_t klass_part(intptr_t v) {
 692     intptr_t r = v & type_klass_mask;
 693     assert (r != 0, "invalid");
 694     return r;
 695   }
 696 
 697   // type recorded
 698   static Klass* valid_klass(intptr_t k) {
 699     if (!is_type_none(k) &&
 700         !is_type_unknown(k)) {
 701       return (Klass*)klass_part(k);
 702     } else {
 703       return NULL;
 704     }
 705   }
 706 
 707   static intptr_t with_status(intptr_t k, intptr_t in) {
 708     return k | (in & status_bits);
 709   }
 710 
 711   static intptr_t with_status(Klass* k, intptr_t in) {
 712     return with_status((intptr_t)k, in);
 713   }
 714 
 715 #ifndef PRODUCT
 716   static void print_klass(outputStream* st, intptr_t k);
 717 #endif
 718 
 719   // GC support
 720   static bool is_loader_alive(BoolObjectClosure* is_alive_cl, intptr_t p);
 721 
 722 protected:
 723   // ProfileData object these entries are part of
 724   ProfileData* _pd;
 725   // offset within the ProfileData object where the entries start
 726   const int _base_off;
 727 
 728   TypeEntries(int base_off)
 729     : _base_off(base_off), _pd(NULL) {}
 730 
 731   void set_intptr_at(int index, intptr_t value) {
 732     _pd->set_intptr_at(index, value);
 733   }
 734 
 735   intptr_t intptr_at(int index) const {
 736     return _pd->intptr_at(index);
 737   }
 738 
 739 public:
 740   void set_profile_data(ProfileData* pd) {
 741     _pd = pd;
 742   }
 743 };
 744 
 745 // Type entries used for arguments passed at a call and parameters on
 746 // method entry. 2 cells per entry: one for the type encoded as in
 747 // TypeEntries and one initialized with the stack slot where the
 748 // profiled object is to be found so that the interpreter can locate
 749 // it quickly.
 750 class TypeStackSlotEntries : public TypeEntries {
 751 
 752 private:
 753   enum {
 754     stack_slot_entry,
 755     type_entry,
 756     per_arg_cell_count
 757   };
 758 
 759   // offset of cell for stack slot for entry i within ProfileData object
 760   int stack_slot_offset(int i) const {
 761     return _base_off + stack_slot_local_offset(i);
 762   }
 763 
 764 protected:
 765   const int _number_of_entries;
 766 
 767   // offset of cell for type for entry i within ProfileData object
 768   int type_offset(int i) const {
 769     return _base_off + type_local_offset(i);
 770   }
 771 
 772 public:
 773 
 774   TypeStackSlotEntries(int base_off, int nb_entries)
 775     : TypeEntries(base_off), _number_of_entries(nb_entries) {}
 776 
 777   static int compute_cell_count(Symbol* signature, bool include_receiver, int max);
 778 
 779   void post_initialize(Symbol* signature, bool has_receiver, bool include_receiver);
 780 
 781   // offset of cell for stack slot for entry i within this block of cells for a TypeStackSlotEntries
 782   static int stack_slot_local_offset(int i) {
 783     return i * per_arg_cell_count + stack_slot_entry;
 784   }
 785 
 786   // offset of cell for type for entry i within this block of cells for a TypeStackSlotEntries
 787   static int type_local_offset(int i) {
 788     return i * per_arg_cell_count + type_entry;
 789   }
 790 
 791   // stack slot for entry i
 792   uint stack_slot(int i) const {
 793     assert(i >= 0 && i < _number_of_entries, "oob");
 794     return _pd->uint_at(stack_slot_offset(i));
 795   }
 796 
 797   // set stack slot for entry i
 798   void set_stack_slot(int i, uint num) {
 799     assert(i >= 0 && i < _number_of_entries, "oob");
 800     _pd->set_uint_at(stack_slot_offset(i), num);
 801   }
 802 
 803   // type for entry i
 804   intptr_t type(int i) const {
 805     assert(i >= 0 && i < _number_of_entries, "oob");
 806     return _pd->intptr_at(type_offset(i));
 807   }
 808 
 809   // set type for entry i
 810   void set_type(int i, intptr_t k) {
 811     assert(i >= 0 && i < _number_of_entries, "oob");
 812     _pd->set_intptr_at(type_offset(i), k);
 813   }
 814 
 815   static ByteSize per_arg_size() {
 816     return in_ByteSize(per_arg_cell_count * DataLayout::cell_size);
 817   }
 818 
 819   static int per_arg_count() {
 820     return per_arg_cell_count ;
 821   }
 822 
 823   // GC support
 824   void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
 825 
 826 #ifndef PRODUCT
 827   void print_data_on(outputStream* st) const;
 828 #endif
 829 };
 830 
 831 // Type entry used for return from a call. A single cell to record the
 832 // type.
 833 class ReturnTypeEntry : public TypeEntries {
 834 
 835 private:
 836   enum {
 837     cell_count = 1
 838   };
 839 
 840 public:
 841   ReturnTypeEntry(int base_off)
 842     : TypeEntries(base_off) {}
 843 
 844   void post_initialize() {
 845     set_type(type_none());
 846   }
 847 
 848   intptr_t type() const {
 849     return _pd->intptr_at(_base_off);
 850   }
 851 
 852   void set_type(intptr_t k) {
 853     _pd->set_intptr_at(_base_off, k);
 854   }
 855 
 856   static int static_cell_count() {
 857     return cell_count;
 858   }
 859 
 860   static ByteSize size() {
 861     return in_ByteSize(cell_count * DataLayout::cell_size);
 862   }
 863 
 864   ByteSize type_offset() {
 865     return DataLayout::cell_offset(_base_off);
 866   }
 867 
 868   // GC support
 869   void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
 870 
 871 #ifndef PRODUCT
 872   void print_data_on(outputStream* st) const;
 873 #endif
 874 };
 875 
 876 // Entries to collect type information at a call: contains arguments
 877 // (TypeStackSlotEntries), a return type (ReturnTypeEntry) and a
 878 // number of cells. Because the number of cells for the return type is
 879 // smaller than the number of cells for the type of an arguments, the
 880 // number of cells is used to tell how many arguments are profiled and
 881 // whether a return value is profiled. See has_arguments() and
 882 // has_return().
 883 class TypeEntriesAtCall {
 884 private:
 885   static int stack_slot_local_offset(int i) {
 886     return header_cell_count() + TypeStackSlotEntries::stack_slot_local_offset(i);
 887   }
 888 
 889   static int argument_type_local_offset(int i) {
 890     return header_cell_count() + TypeStackSlotEntries::type_local_offset(i);;
 891   }
 892 
 893 public:
 894 
 895   static int header_cell_count() {
 896     return 1;
 897   }
 898 
 899   static int cell_count_local_offset() {
 900     return 0;
 901   }
 902 
 903   static int compute_cell_count(BytecodeStream* stream);
 904 
 905   static void initialize(DataLayout* dl, int base, int cell_count) {
 906     int off = base + cell_count_local_offset();
 907     dl->set_cell_at(off, cell_count - base - header_cell_count());
 908   }
 909 
 910   static bool arguments_profiling_enabled();
 911   static bool return_profiling_enabled();
 912 
 913   // Code generation support
 914   static ByteSize cell_count_offset() {
 915     return in_ByteSize(cell_count_local_offset() * DataLayout::cell_size);
 916   }
 917 
 918   static ByteSize args_data_offset() {
 919     return in_ByteSize(header_cell_count() * DataLayout::cell_size);
 920   }
 921 
 922   static ByteSize stack_slot_offset(int i) {
 923     return in_ByteSize(stack_slot_local_offset(i) * DataLayout::cell_size);
 924   }
 925 
 926   static ByteSize argument_type_offset(int i) {
 927     return in_ByteSize(argument_type_local_offset(i) * DataLayout::cell_size);
 928   }
 929 };
 930 
 931 // CallTypeData
 932 //
 933 // A CallTypeData is used to access profiling information about a non
 934 // virtual call for which we collect type information about arguments
 935 // and return value.
 936 class CallTypeData : public CounterData {
 937 private:
 938   // entries for arguments if any
 939   TypeStackSlotEntries _args;
 940   // entry for return type if any
 941   ReturnTypeEntry _ret;
 942 
 943   int cell_count_global_offset() const {
 944     return CounterData::static_cell_count() + TypeEntriesAtCall::cell_count_local_offset();
 945   }
 946 
 947   // number of cells not counting the header
 948   int cell_count_no_header() const {
 949     return uint_at(cell_count_global_offset());
 950   }
 951 
 952   void check_number_of_arguments(int total) {
 953     assert(number_of_arguments() == total, "should be set in DataLayout::initialize");
 954   }
 955 
 956 public:
 957   CallTypeData(DataLayout* layout) :
 958     CounterData(layout),
 959     _args(CounterData::static_cell_count()+TypeEntriesAtCall::header_cell_count(), number_of_arguments()),
 960     _ret(cell_count() - ReturnTypeEntry::static_cell_count())
 961   {
 962     assert(layout->tag() == DataLayout::call_type_data_tag, "wrong type");
 963     // Some compilers (VC++) don't want this passed in member initialization list
 964     _args.set_profile_data(this);
 965     _ret.set_profile_data(this);
 966   }
 967 
 968   const TypeStackSlotEntries* args() const {
 969     assert(has_arguments(), "no profiling of arguments");
 970     return &_args;
 971   }
 972 
 973   const ReturnTypeEntry* ret() const {
 974     assert(has_return(), "no profiling of return value");
 975     return &_ret;
 976   }
 977 
 978   virtual bool is_CallTypeData() const { return true; }
 979 
 980   static int static_cell_count() {
 981     return -1;
 982   }
 983 
 984   static int compute_cell_count(BytecodeStream* stream) {
 985     return CounterData::static_cell_count() + TypeEntriesAtCall::compute_cell_count(stream);
 986   }
 987 
 988   static void initialize(DataLayout* dl, int cell_count) {
 989     TypeEntriesAtCall::initialize(dl, CounterData::static_cell_count(), cell_count);
 990   }
 991 
 992   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
 993 
 994   virtual int cell_count() const {
 995     return CounterData::static_cell_count() +
 996       TypeEntriesAtCall::header_cell_count() +
 997       int_at_unchecked(cell_count_global_offset());
 998   }
 999 
1000   int number_of_arguments() const {
1001     return cell_count_no_header() / TypeStackSlotEntries::per_arg_count();
1002   }
1003 
1004   void set_argument_type(int i, Klass* k) {
1005     assert(has_arguments(), "no arguments!");
1006     intptr_t current = _args.type(i);
1007     _args.set_type(i, TypeEntries::with_status(k, current));
1008   }
1009 
1010   void set_return_type(Klass* k) {
1011     assert(has_return(), "no return!");
1012     intptr_t current = _ret.type();
1013     _ret.set_type(TypeEntries::with_status(k, current));
1014   }
1015 
1016   // An entry for a return value takes less space than an entry for an
1017   // argument so if the number of cells exceeds the number of cells
1018   // needed for an argument, this object contains type information for
1019   // at least one argument.
1020   bool has_arguments() const {
1021     bool res = cell_count_no_header() >= TypeStackSlotEntries::per_arg_count();
1022     assert (!res || TypeEntriesAtCall::arguments_profiling_enabled(), "no profiling of arguments");
1023     return res;
1024   }
1025 
1026   // An entry for a return value takes less space than an entry for an
1027   // argument, so if the remainder of the number of cells divided by
1028   // the number of cells for an argument is not null, a return value
1029   // is profiled in this object.
1030   bool has_return() const {
1031     bool res = (cell_count_no_header() % TypeStackSlotEntries::per_arg_count()) != 0;
1032     assert (!res || TypeEntriesAtCall::return_profiling_enabled(), "no profiling of return values");
1033     return res;
1034   }
1035 
1036   // Code generation support
1037   static ByteSize args_data_offset() {
1038     return cell_offset(CounterData::static_cell_count()) + TypeEntriesAtCall::args_data_offset();
1039   }
1040 
1041   // GC support
1042   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {
1043     if (has_arguments()) {
1044       _args.clean_weak_klass_links(is_alive_closure);
1045     }
1046     if (has_return()) {
1047       _ret.clean_weak_klass_links(is_alive_closure);
1048     }
1049   }
1050 
1051 #ifndef PRODUCT
1052   virtual void print_data_on(outputStream* st) const;
1053 #endif
1054 };
1055 
1056 // ReceiverTypeData
1057 //
1058 // A ReceiverTypeData is used to access profiling information about a
1059 // dynamic type check.  It consists of a counter which counts the total times
1060 // that the check is reached, and a series of (Klass*, count) pairs
1061 // which are used to store a type profile for the receiver of the check.
1062 class ReceiverTypeData : public CounterData {
1063 protected:
1064   enum {
1065     receiver0_offset = counter_cell_count,
1066     count0_offset,
1067     receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
1068   };
1069 
1070 public:
1071   ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
1072     assert(layout->tag() == DataLayout::receiver_type_data_tag ||
1073            layout->tag() == DataLayout::virtual_call_data_tag ||
1074            layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1075   }
1076 
1077   virtual bool is_ReceiverTypeData() const { return true; }
1078 
1079   static int static_cell_count() {
1080     return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count;
1081   }
1082 
1083   virtual int cell_count() const {
1084     return static_cell_count();
1085   }
1086 
1087   // Direct accessors
1088   static uint row_limit() {
1089     return TypeProfileWidth;
1090   }
1091   static int receiver_cell_index(uint row) {
1092     return receiver0_offset + row * receiver_type_row_cell_count;
1093   }
1094   static int receiver_count_cell_index(uint row) {
1095     return count0_offset + row * receiver_type_row_cell_count;
1096   }
1097 
1098   Klass* receiver(uint row) const {
1099     assert(row < row_limit(), "oob");
1100 
1101     Klass* recv = (Klass*)intptr_at(receiver_cell_index(row));
1102     assert(recv == NULL || recv->is_klass(), "wrong type");
1103     return recv;
1104   }
1105 
1106   void set_receiver(uint row, Klass* k) {
1107     assert((uint)row < row_limit(), "oob");
1108     set_intptr_at(receiver_cell_index(row), (uintptr_t)k);
1109   }
1110 
1111   uint receiver_count(uint row) const {
1112     assert(row < row_limit(), "oob");
1113     return uint_at(receiver_count_cell_index(row));
1114   }
1115 
1116   void set_receiver_count(uint row, uint count) {
1117     assert(row < row_limit(), "oob");
1118     set_uint_at(receiver_count_cell_index(row), count);
1119   }
1120 
1121   void clear_row(uint row) {
1122     assert(row < row_limit(), "oob");
1123     // Clear total count - indicator of polymorphic call site.
1124     // The site may look like as monomorphic after that but
1125     // it allow to have more accurate profiling information because
1126     // there was execution phase change since klasses were unloaded.
1127     // If the site is still polymorphic then MDO will be updated
1128     // to reflect it. But it could be the case that the site becomes
1129     // only bimorphic. Then keeping total count not 0 will be wrong.
1130     // Even if we use monomorphic (when it is not) for compilation
1131     // we will only have trap, deoptimization and recompile again
1132     // with updated MDO after executing method in Interpreter.
1133     // An additional receiver will be recorded in the cleaned row
1134     // during next call execution.
1135     //
1136     // Note: our profiling logic works with empty rows in any slot.
1137     // We do sorting a profiling info (ciCallProfile) for compilation.
1138     //
1139     set_count(0);
1140     set_receiver(row, NULL);
1141     set_receiver_count(row, 0);
1142   }
1143 
1144   // Code generation support
1145   static ByteSize receiver_offset(uint row) {
1146     return cell_offset(receiver_cell_index(row));
1147   }
1148   static ByteSize receiver_count_offset(uint row) {
1149     return cell_offset(receiver_count_cell_index(row));
1150   }
1151   static ByteSize receiver_type_data_size() {
1152     return cell_offset(static_cell_count());
1153   }
1154 
1155   // GC support
1156   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
1157 
1158 #ifndef PRODUCT
1159   void print_receiver_data_on(outputStream* st) const;
1160   void print_data_on(outputStream* st) const;
1161 #endif
1162 };
1163 
1164 // VirtualCallData
1165 //
1166 // A VirtualCallData is used to access profiling information about a
1167 // virtual call.  For now, it has nothing more than a ReceiverTypeData.
1168 class VirtualCallData : public ReceiverTypeData {
1169 public:
1170   VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
1171     assert(layout->tag() == DataLayout::virtual_call_data_tag ||
1172            layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1173   }
1174 
1175   virtual bool is_VirtualCallData() const { return true; }
1176 
1177   static int static_cell_count() {
1178     // At this point we could add more profile state, e.g., for arguments.
1179     // But for now it's the same size as the base record type.
1180     return ReceiverTypeData::static_cell_count();
1181   }
1182 
1183   virtual int cell_count() const {
1184     return static_cell_count();
1185   }
1186 
1187   // Direct accessors
1188   static ByteSize virtual_call_data_size() {
1189     return cell_offset(static_cell_count());
1190   }
1191 
1192 #ifndef PRODUCT
1193   void print_data_on(outputStream* st) const;
1194 #endif
1195 };
1196 
1197 // VirtualCallTypeData
1198 //
1199 // A VirtualCallTypeData is used to access profiling information about
1200 // a virtual call for which we collect type information about
1201 // arguments and return value.
1202 class VirtualCallTypeData : public VirtualCallData {
1203 private:
1204   // entries for arguments if any
1205   TypeStackSlotEntries _args;
1206   // entry for return type if any
1207   ReturnTypeEntry _ret;
1208 
1209   int cell_count_global_offset() const {
1210     return VirtualCallData::static_cell_count() + TypeEntriesAtCall::cell_count_local_offset();
1211   }
1212 
1213   // number of cells not counting the header
1214   int cell_count_no_header() const {
1215     return uint_at(cell_count_global_offset());
1216   }
1217 
1218   void check_number_of_arguments(int total) {
1219     assert(number_of_arguments() == total, "should be set in DataLayout::initialize");
1220   }
1221 
1222 public:
1223   VirtualCallTypeData(DataLayout* layout) :
1224     VirtualCallData(layout),
1225     _args(VirtualCallData::static_cell_count()+TypeEntriesAtCall::header_cell_count(), number_of_arguments()),
1226     _ret(cell_count() - ReturnTypeEntry::static_cell_count())
1227   {
1228     assert(layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1229     // Some compilers (VC++) don't want this passed in member initialization list
1230     _args.set_profile_data(this);
1231     _ret.set_profile_data(this);
1232   }
1233 
1234   const TypeStackSlotEntries* args() const {
1235     assert(has_arguments(), "no profiling of arguments");
1236     return &_args;
1237   }
1238 
1239   const ReturnTypeEntry* ret() const {
1240     assert(has_return(), "no profiling of return value");
1241     return &_ret;
1242   }
1243 
1244   virtual bool is_VirtualCallTypeData() const { return true; }
1245 
1246   static int static_cell_count() {
1247     return -1;
1248   }
1249 
1250   static int compute_cell_count(BytecodeStream* stream) {
1251     return VirtualCallData::static_cell_count() + TypeEntriesAtCall::compute_cell_count(stream);
1252   }
1253 
1254   static void initialize(DataLayout* dl, int cell_count) {
1255     TypeEntriesAtCall::initialize(dl, VirtualCallData::static_cell_count(), cell_count);
1256   }
1257 
1258   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1259 
1260   virtual int cell_count() const {
1261     return VirtualCallData::static_cell_count() +
1262       TypeEntriesAtCall::header_cell_count() +
1263       int_at_unchecked(cell_count_global_offset());
1264   }
1265 
1266   int number_of_arguments() const {
1267     return cell_count_no_header() / TypeStackSlotEntries::per_arg_count();
1268   }
1269 
1270   void set_argument_type(int i, Klass* k) {
1271     assert(has_arguments(), "no arguments!");
1272     intptr_t current = _args.type(i);
1273     _args.set_type(i, TypeEntries::with_status(k, current));
1274   }
1275 
1276   void set_return_type(Klass* k) {
1277     assert(has_return(), "no return!");
1278     intptr_t current = _ret.type();
1279     _ret.set_type(TypeEntries::with_status(k, current));
1280   }
1281 
1282   // An entry for a return value takes less space than an entry for an
1283   // argument, so if the remainder of the number of cells divided by
1284   // the number of cells for an argument is not null, a return value
1285   // is profiled in this object.
1286   bool has_return() const {
1287     bool res = (cell_count_no_header() % TypeStackSlotEntries::per_arg_count()) != 0;
1288     assert (!res || TypeEntriesAtCall::return_profiling_enabled(), "no profiling of return values");
1289     return res;
1290   }
1291 
1292   // An entry for a return value takes less space than an entry for an
1293   // argument so if the number of cells exceeds the number of cells
1294   // needed for an argument, this object contains type information for
1295   // at least one argument.
1296   bool has_arguments() const {
1297     bool res = cell_count_no_header() >= TypeStackSlotEntries::per_arg_count();
1298     assert (!res || TypeEntriesAtCall::arguments_profiling_enabled(), "no profiling of arguments");
1299     return res;
1300   }
1301 
1302   // Code generation support
1303   static ByteSize args_data_offset() {
1304     return cell_offset(VirtualCallData::static_cell_count()) + TypeEntriesAtCall::args_data_offset();
1305   }
1306 
1307   // GC support
1308   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {
1309     ReceiverTypeData::clean_weak_klass_links(is_alive_closure);
1310     if (has_arguments()) {
1311       _args.clean_weak_klass_links(is_alive_closure);
1312     }
1313     if (has_return()) {
1314       _ret.clean_weak_klass_links(is_alive_closure);
1315     }
1316   }
1317 
1318 #ifndef PRODUCT
1319   virtual void print_data_on(outputStream* st) const;
1320 #endif
1321 };
1322 
1323 // RetData
1324 //
1325 // A RetData is used to access profiling information for a ret bytecode.
1326 // It is composed of a count of the number of times that the ret has
1327 // been executed, followed by a series of triples of the form
1328 // (bci, count, di) which count the number of times that some bci was the
1329 // target of the ret and cache a corresponding data displacement.
1330 class RetData : public CounterData {
1331 protected:
1332   enum {
1333     bci0_offset = counter_cell_count,
1334     count0_offset,
1335     displacement0_offset,
1336     ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
1337   };
1338 
1339   void set_bci(uint row, int bci) {
1340     assert((uint)row < row_limit(), "oob");
1341     set_int_at(bci0_offset + row * ret_row_cell_count, bci);
1342   }
1343   void release_set_bci(uint row, int bci) {
1344     assert((uint)row < row_limit(), "oob");
1345     // 'release' when setting the bci acts as a valid flag for other
1346     // threads wrt bci_count and bci_displacement.
1347     release_set_int_at(bci0_offset + row * ret_row_cell_count, bci);
1348   }
1349   void set_bci_count(uint row, uint count) {
1350     assert((uint)row < row_limit(), "oob");
1351     set_uint_at(count0_offset + row * ret_row_cell_count, count);
1352   }
1353   void set_bci_displacement(uint row, int disp) {
1354     set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
1355   }
1356 
1357 public:
1358   RetData(DataLayout* layout) : CounterData(layout) {
1359     assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
1360   }
1361 
1362   virtual bool is_RetData() const { return true; }
1363 
1364   enum {
1365     no_bci = -1 // value of bci when bci1/2 are not in use.
1366   };
1367 
1368   static int static_cell_count() {
1369     return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
1370   }
1371 
1372   virtual int cell_count() const {
1373     return static_cell_count();
1374   }
1375 
1376   static uint row_limit() {
1377     return BciProfileWidth;
1378   }
1379   static int bci_cell_index(uint row) {
1380     return bci0_offset + row * ret_row_cell_count;
1381   }
1382   static int bci_count_cell_index(uint row) {
1383     return count0_offset + row * ret_row_cell_count;
1384   }
1385   static int bci_displacement_cell_index(uint row) {
1386     return displacement0_offset + row * ret_row_cell_count;
1387   }
1388 
1389   // Direct accessors
1390   int bci(uint row) const {
1391     return int_at(bci_cell_index(row));
1392   }
1393   uint bci_count(uint row) const {
1394     return uint_at(bci_count_cell_index(row));
1395   }
1396   int bci_displacement(uint row) const {
1397     return int_at(bci_displacement_cell_index(row));
1398   }
1399 
1400   // Interpreter Runtime support
1401   address fixup_ret(int return_bci, MethodData* mdo);
1402 
1403   // Code generation support
1404   static ByteSize bci_offset(uint row) {
1405     return cell_offset(bci_cell_index(row));
1406   }
1407   static ByteSize bci_count_offset(uint row) {
1408     return cell_offset(bci_count_cell_index(row));
1409   }
1410   static ByteSize bci_displacement_offset(uint row) {
1411     return cell_offset(bci_displacement_cell_index(row));
1412   }
1413 
1414   // Specific initialization.
1415   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1416 
1417 #ifndef PRODUCT
1418   void print_data_on(outputStream* st) const;
1419 #endif
1420 };
1421 
1422 // BranchData
1423 //
1424 // A BranchData is used to access profiling data for a two-way branch.
1425 // It consists of taken and not_taken counts as well as a data displacement
1426 // for the taken case.
1427 class BranchData : public JumpData {
1428 protected:
1429   enum {
1430     not_taken_off_set = jump_cell_count,
1431     branch_cell_count
1432   };
1433 
1434   void set_displacement(int displacement) {
1435     set_int_at(displacement_off_set, displacement);
1436   }
1437 
1438 public:
1439   BranchData(DataLayout* layout) : JumpData(layout) {
1440     assert(layout->tag() == DataLayout::branch_data_tag, "wrong type");
1441   }
1442 
1443   virtual bool is_BranchData() const { return true; }
1444 
1445   static int static_cell_count() {
1446     return branch_cell_count;
1447   }
1448 
1449   virtual int cell_count() const {
1450     return static_cell_count();
1451   }
1452 
1453   // Direct accessor
1454   uint not_taken() const {
1455     return uint_at(not_taken_off_set);
1456   }
1457 
1458   void set_not_taken(uint cnt) {
1459     set_uint_at(not_taken_off_set, cnt);
1460   }
1461 
1462   uint inc_not_taken() {
1463     uint cnt = not_taken() + 1;
1464     // Did we wrap? Will compiler screw us??
1465     if (cnt == 0) cnt--;
1466     set_uint_at(not_taken_off_set, cnt);
1467     return cnt;
1468   }
1469 
1470   // Code generation support
1471   static ByteSize not_taken_offset() {
1472     return cell_offset(not_taken_off_set);
1473   }
1474   static ByteSize branch_data_size() {
1475     return cell_offset(branch_cell_count);
1476   }
1477 
1478   // Specific initialization.
1479   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1480 
1481 #ifndef PRODUCT
1482   void print_data_on(outputStream* st) const;
1483 #endif
1484 };
1485 
1486 // ArrayData
1487 //
1488 // A ArrayData is a base class for accessing profiling data which does
1489 // not have a statically known size.  It consists of an array length
1490 // and an array start.
1491 class ArrayData : public ProfileData {
1492 protected:
1493   friend class DataLayout;
1494 
1495   enum {
1496     array_len_off_set,
1497     array_start_off_set
1498   };
1499 
1500   uint array_uint_at(int index) const {
1501     int aindex = index + array_start_off_set;
1502     return uint_at(aindex);
1503   }
1504   int array_int_at(int index) const {
1505     int aindex = index + array_start_off_set;
1506     return int_at(aindex);
1507   }
1508   oop array_oop_at(int index) const {
1509     int aindex = index + array_start_off_set;
1510     return oop_at(aindex);
1511   }
1512   void array_set_int_at(int index, int value) {
1513     int aindex = index + array_start_off_set;
1514     set_int_at(aindex, value);
1515   }
1516 
1517   // Code generation support for subclasses.
1518   static ByteSize array_element_offset(int index) {
1519     return cell_offset(array_start_off_set + index);
1520   }
1521 
1522 public:
1523   ArrayData(DataLayout* layout) : ProfileData(layout) {}
1524 
1525   virtual bool is_ArrayData() const { return true; }
1526 
1527   static int static_cell_count() {
1528     return -1;
1529   }
1530 
1531   int array_len() const {
1532     return int_at_unchecked(array_len_off_set);
1533   }
1534 
1535   virtual int cell_count() const {
1536     return array_len() + 1;
1537   }
1538 
1539   // Code generation support
1540   static ByteSize array_len_offset() {
1541     return cell_offset(array_len_off_set);
1542   }
1543   static ByteSize array_start_offset() {
1544     return cell_offset(array_start_off_set);
1545   }
1546 };
1547 
1548 // MultiBranchData
1549 //
1550 // A MultiBranchData is used to access profiling information for
1551 // a multi-way branch (*switch bytecodes).  It consists of a series
1552 // of (count, displacement) pairs, which count the number of times each
1553 // case was taken and specify the data displacment for each branch target.
1554 class MultiBranchData : public ArrayData {
1555 protected:
1556   enum {
1557     default_count_off_set,
1558     default_disaplacement_off_set,
1559     case_array_start
1560   };
1561   enum {
1562     relative_count_off_set,
1563     relative_displacement_off_set,
1564     per_case_cell_count
1565   };
1566 
1567   void set_default_displacement(int displacement) {
1568     array_set_int_at(default_disaplacement_off_set, displacement);
1569   }
1570   void set_displacement_at(int index, int displacement) {
1571     array_set_int_at(case_array_start +
1572                      index * per_case_cell_count +
1573                      relative_displacement_off_set,
1574                      displacement);
1575   }
1576 
1577 public:
1578   MultiBranchData(DataLayout* layout) : ArrayData(layout) {
1579     assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
1580   }
1581 
1582   virtual bool is_MultiBranchData() const { return true; }
1583 
1584   static int compute_cell_count(BytecodeStream* stream);
1585 
1586   int number_of_cases() const {
1587     int alen = array_len() - 2; // get rid of default case here.
1588     assert(alen % per_case_cell_count == 0, "must be even");
1589     return (alen / per_case_cell_count);
1590   }
1591 
1592   uint default_count() const {
1593     return array_uint_at(default_count_off_set);
1594   }
1595   int default_displacement() const {
1596     return array_int_at(default_disaplacement_off_set);
1597   }
1598 
1599   uint count_at(int index) const {
1600     return array_uint_at(case_array_start +
1601                          index * per_case_cell_count +
1602                          relative_count_off_set);
1603   }
1604   int displacement_at(int index) const {
1605     return array_int_at(case_array_start +
1606                         index * per_case_cell_count +
1607                         relative_displacement_off_set);
1608   }
1609 
1610   // Code generation support
1611   static ByteSize default_count_offset() {
1612     return array_element_offset(default_count_off_set);
1613   }
1614   static ByteSize default_displacement_offset() {
1615     return array_element_offset(default_disaplacement_off_set);
1616   }
1617   static ByteSize case_count_offset(int index) {
1618     return case_array_offset() +
1619            (per_case_size() * index) +
1620            relative_count_offset();
1621   }
1622   static ByteSize case_array_offset() {
1623     return array_element_offset(case_array_start);
1624   }
1625   static ByteSize per_case_size() {
1626     return in_ByteSize(per_case_cell_count) * cell_size;
1627   }
1628   static ByteSize relative_count_offset() {
1629     return in_ByteSize(relative_count_off_set) * cell_size;
1630   }
1631   static ByteSize relative_displacement_offset() {
1632     return in_ByteSize(relative_displacement_off_set) * cell_size;
1633   }
1634 
1635   // Specific initialization.
1636   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1637 
1638 #ifndef PRODUCT
1639   void print_data_on(outputStream* st) const;
1640 #endif
1641 };
1642 
1643 class ArgInfoData : public ArrayData {
1644 
1645 public:
1646   ArgInfoData(DataLayout* layout) : ArrayData(layout) {
1647     assert(layout->tag() == DataLayout::arg_info_data_tag, "wrong type");
1648   }
1649 
1650   virtual bool is_ArgInfoData() const { return true; }
1651 
1652 
1653   int number_of_args() const {
1654     return array_len();
1655   }
1656 
1657   uint arg_modified(int arg) const {
1658     return array_uint_at(arg);
1659   }
1660 
1661   void set_arg_modified(int arg, uint val) {
1662     array_set_int_at(arg, val);
1663   }
1664 
1665 #ifndef PRODUCT
1666   void print_data_on(outputStream* st) const;
1667 #endif
1668 };
1669 
1670 // ParametersTypeData
1671 //
1672 // A ParametersTypeData is used to access profiling information about
1673 // types of parameters to a method
1674 class ParametersTypeData : public ArrayData {
1675 
1676 private:
1677   TypeStackSlotEntries _parameters;
1678 
1679   static int stack_slot_local_offset(int i) {
1680     assert_profiling_enabled();
1681     return array_start_off_set + TypeStackSlotEntries::stack_slot_local_offset(i);
1682   }
1683 
1684   static int type_local_offset(int i) {
1685     assert_profiling_enabled();
1686     return array_start_off_set + TypeStackSlotEntries::type_local_offset(i);
1687   }
1688 
1689   static bool profiling_enabled();
1690   static void assert_profiling_enabled() {
1691     assert(profiling_enabled(), "method parameters profiling should be on");
1692   }
1693 
1694 public:
1695   ParametersTypeData(DataLayout* layout) : ArrayData(layout), _parameters(1, number_of_parameters()) {
1696     assert(layout->tag() == DataLayout::parameters_type_data_tag, "wrong type");
1697     // Some compilers (VC++) don't want this passed in member initialization list
1698     _parameters.set_profile_data(this);
1699   }
1700 
1701   static int compute_cell_count(Method* m);
1702 
1703   virtual bool is_ParametersTypeData() const { return true; }
1704 
1705   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1706 
1707   int number_of_parameters() const {
1708     return array_len() / TypeStackSlotEntries::per_arg_count();
1709   }
1710 
1711   const TypeStackSlotEntries* parameters() const { return &_parameters; }
1712 
1713   uint stack_slot(int i) const {
1714     return _parameters.stack_slot(i);
1715   }
1716 
1717   void set_type(int i, Klass* k) {
1718     intptr_t current = _parameters.type(i);
1719     _parameters.set_type(i, TypeEntries::with_status((intptr_t)k, current));
1720   }
1721 
1722   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {
1723     _parameters.clean_weak_klass_links(is_alive_closure);
1724   }
1725 
1726 #ifndef PRODUCT
1727   virtual void print_data_on(outputStream* st) const;
1728 #endif
1729 
1730   static ByteSize stack_slot_offset(int i) {
1731     return cell_offset(stack_slot_local_offset(i));
1732   }
1733 
1734   static ByteSize type_offset(int i) {
1735     return cell_offset(type_local_offset(i));
1736   }
1737 };
1738 
1739 // MethodData*
1740 //
1741 // A MethodData* holds information which has been collected about
1742 // a method.  Its layout looks like this:
1743 //
1744 // -----------------------------
1745 // | header                    |
1746 // | klass                     |
1747 // -----------------------------
1748 // | method                    |
1749 // | size of the MethodData* |
1750 // -----------------------------
1751 // | Data entries...           |
1752 // |   (variable size)         |
1753 // |                           |
1754 // .                           .
1755 // .                           .
1756 // .                           .
1757 // |                           |
1758 // -----------------------------
1759 //
1760 // The data entry area is a heterogeneous array of DataLayouts. Each
1761 // DataLayout in the array corresponds to a specific bytecode in the
1762 // method.  The entries in the array are sorted by the corresponding
1763 // bytecode.  Access to the data is via resource-allocated ProfileData,
1764 // which point to the underlying blocks of DataLayout structures.
1765 //
1766 // During interpretation, if profiling in enabled, the interpreter
1767 // maintains a method data pointer (mdp), which points at the entry
1768 // in the array corresponding to the current bci.  In the course of
1769 // intepretation, when a bytecode is encountered that has profile data
1770 // associated with it, the entry pointed to by mdp is updated, then the
1771 // mdp is adjusted to point to the next appropriate DataLayout.  If mdp
1772 // is NULL to begin with, the interpreter assumes that the current method
1773 // is not (yet) being profiled.
1774 //
1775 // In MethodData* parlance, "dp" is a "data pointer", the actual address
1776 // of a DataLayout element.  A "di" is a "data index", the offset in bytes
1777 // from the base of the data entry array.  A "displacement" is the byte offset
1778 // in certain ProfileData objects that indicate the amount the mdp must be
1779 // adjusted in the event of a change in control flow.
1780 //
1781 
1782 class MethodData : public Metadata {
1783   friend class VMStructs;
1784 private:
1785   friend class ProfileData;
1786 
1787   // Back pointer to the Method*
1788   Method* _method;
1789 
1790   // Size of this oop in bytes
1791   int _size;
1792 
1793   // Cached hint for bci_to_dp and bci_to_data
1794   int _hint_di;
1795 
1796   MethodData(methodHandle method, int size, TRAPS);
1797 public:
1798   static MethodData* allocate(ClassLoaderData* loader_data, methodHandle method, TRAPS);
1799   MethodData() {}; // For ciMethodData
1800 
1801   bool is_methodData() const volatile { return true; }
1802 
1803   // Whole-method sticky bits and flags
1804   enum {
1805     _trap_hist_limit    = 17,   // decoupled from Deoptimization::Reason_LIMIT
1806     _trap_hist_mask     = max_jubyte,
1807     _extra_data_count   = 4     // extra DataLayout headers, for trap history
1808   }; // Public flag values
1809 private:
1810   uint _nof_decompiles;             // count of all nmethod removals
1811   uint _nof_overflow_recompiles;    // recompile count, excluding recomp. bits
1812   uint _nof_overflow_traps;         // trap count, excluding _trap_hist
1813   union {
1814     intptr_t _align;
1815     u1 _array[_trap_hist_limit];
1816   } _trap_hist;
1817 
1818   // Support for interprocedural escape analysis, from Thomas Kotzmann.
1819   intx              _eflags;          // flags on escape information
1820   intx              _arg_local;       // bit set of non-escaping arguments
1821   intx              _arg_stack;       // bit set of stack-allocatable arguments
1822   intx              _arg_returned;    // bit set of returned arguments
1823 
1824   int _creation_mileage;              // method mileage at MDO creation
1825 
1826   // How many invocations has this MDO seen?
1827   // These counters are used to determine the exact age of MDO.
1828   // We need those because in tiered a method can be concurrently
1829   // executed at different levels.
1830   InvocationCounter _invocation_counter;
1831   // Same for backedges.
1832   InvocationCounter _backedge_counter;
1833   // Counter values at the time profiling started.
1834   int               _invocation_counter_start;
1835   int               _backedge_counter_start;
1836   // Number of loops and blocks is computed when compiling the first
1837   // time with C1. It is used to determine if method is trivial.
1838   short             _num_loops;
1839   short             _num_blocks;
1840   // Highest compile level this method has ever seen.
1841   u1                _highest_comp_level;
1842   // Same for OSR level
1843   u1                _highest_osr_comp_level;
1844   // Does this method contain anything worth profiling?
1845   bool              _would_profile;
1846 
1847   // Size of _data array in bytes.  (Excludes header and extra_data fields.)
1848   int _data_size;
1849 
1850   // Offset with the MDO for the area dedicated to
1851   // parameters. -1 if no parameter profiling.
1852   int _parameters_type_data_di;
1853 
1854   // Beginning of the data entries
1855   intptr_t _data[1];
1856 
1857   // Helper for size computation
1858   static int compute_data_size(BytecodeStream* stream);
1859   static int bytecode_cell_count(Bytecodes::Code code);
1860   enum { no_profile_data = -1, variable_cell_count = -2 };
1861 
1862   // Helper for initialization
1863   DataLayout* data_layout_at(int data_index) const {
1864     assert(data_index % sizeof(intptr_t) == 0, "unaligned");
1865     return (DataLayout*) (((address)_data) + data_index);
1866   }
1867 
1868   // Initialize an individual data segment.  Returns the size of
1869   // the segment in bytes.
1870   int initialize_data(BytecodeStream* stream, int data_index);
1871 
1872   // Helper for data_at
1873   DataLayout* limit_data_position() const {
1874     return (DataLayout*)((address)data_base() + _data_size);
1875   }
1876   bool out_of_bounds(int data_index) const {
1877     return data_index >= data_size();
1878   }
1879 
1880   // Give each of the data entries a chance to perform specific
1881   // data initialization.
1882   void post_initialize(BytecodeStream* stream);
1883 
1884   // hint accessors
1885   int      hint_di() const  { return _hint_di; }
1886   void set_hint_di(int di)  {
1887     assert(!out_of_bounds(di), "hint_di out of bounds");
1888     _hint_di = di;
1889   }
1890   ProfileData* data_before(int bci) {
1891     // avoid SEGV on this edge case
1892     if (data_size() == 0)
1893       return NULL;
1894     int hint = hint_di();
1895     if (data_layout_at(hint)->bci() <= bci)
1896       return data_at(hint);
1897     return first_data();
1898   }
1899 
1900   // What is the index of the first data entry?
1901   int first_di() const { return 0; }
1902 
1903   // Find or create an extra ProfileData:
1904   ProfileData* bci_to_extra_data(int bci, bool create_if_missing);
1905 
1906   // return the argument info cell
1907   ArgInfoData *arg_info();
1908 
1909   enum {
1910     no_type_profile = 0,
1911     type_profile_jsr292 = 1,
1912     type_profile_all = 2
1913   };
1914 
1915   static bool profile_jsr292(methodHandle m, int bci);
1916   static int profile_arguments_flag();
1917   static bool profile_arguments_jsr292_only();
1918   static bool profile_all_arguments();
1919   static bool profile_arguments_for_invoke(methodHandle m, int bci);
1920   static int profile_return_flag();
1921   static bool profile_all_return();
1922   static bool profile_return_for_invoke(methodHandle m, int bci);
1923   static int profile_parameters_flag();
1924   static bool profile_parameters_jsr292_only();
1925   static bool profile_all_parameters();
1926 
1927 public:
1928   static int header_size() {
1929     return sizeof(MethodData)/wordSize;
1930   }
1931 
1932   // Compute the size of a MethodData* before it is created.
1933   static int compute_allocation_size_in_bytes(methodHandle method);
1934   static int compute_allocation_size_in_words(methodHandle method);
1935   static int compute_extra_data_count(int data_size, int empty_bc_count);
1936 
1937   // Determine if a given bytecode can have profile information.
1938   static bool bytecode_has_profile(Bytecodes::Code code) {
1939     return bytecode_cell_count(code) != no_profile_data;
1940   }
1941 
1942   // reset into original state
1943   void init();
1944 
1945   // My size
1946   int size_in_bytes() const { return _size; }
1947   int size() const    { return align_object_size(align_size_up(_size, BytesPerWord)/BytesPerWord); }
1948 #if INCLUDE_SERVICES
1949   void collect_statistics(KlassSizeStats *sz) const;
1950 #endif
1951 
1952   int      creation_mileage() const  { return _creation_mileage; }
1953   void set_creation_mileage(int x)   { _creation_mileage = x; }
1954 
1955   int invocation_count() {
1956     if (invocation_counter()->carry()) {
1957       return InvocationCounter::count_limit;
1958     }
1959     return invocation_counter()->count();
1960   }
1961   int backedge_count() {
1962     if (backedge_counter()->carry()) {
1963       return InvocationCounter::count_limit;
1964     }
1965     return backedge_counter()->count();
1966   }
1967 
1968   int invocation_count_start() {
1969     if (invocation_counter()->carry()) {
1970       return 0;
1971     }
1972     return _invocation_counter_start;
1973   }
1974 
1975   int backedge_count_start() {
1976     if (backedge_counter()->carry()) {
1977       return 0;
1978     }
1979     return _backedge_counter_start;
1980   }
1981 
1982   int invocation_count_delta() { return invocation_count() - invocation_count_start(); }
1983   int backedge_count_delta()   { return backedge_count()   - backedge_count_start();   }
1984 
1985   void reset_start_counters() {
1986     _invocation_counter_start = invocation_count();
1987     _backedge_counter_start = backedge_count();
1988   }
1989 
1990   InvocationCounter* invocation_counter()     { return &_invocation_counter; }
1991   InvocationCounter* backedge_counter()       { return &_backedge_counter;   }
1992 
1993   void set_would_profile(bool p)              { _would_profile = p;    }
1994   bool would_profile() const                  { return _would_profile; }
1995 
1996   int highest_comp_level() const              { return _highest_comp_level;      }
1997   void set_highest_comp_level(int level)      { _highest_comp_level = level;     }
1998   int highest_osr_comp_level() const          { return _highest_osr_comp_level;  }
1999   void set_highest_osr_comp_level(int level)  { _highest_osr_comp_level = level; }
2000 
2001   int num_loops() const                       { return _num_loops;  }
2002   void set_num_loops(int n)                   { _num_loops = n;     }
2003   int num_blocks() const                      { return _num_blocks; }
2004   void set_num_blocks(int n)                  { _num_blocks = n;    }
2005 
2006   bool is_mature() const;  // consult mileage and ProfileMaturityPercentage
2007   static int mileage_of(Method* m);
2008 
2009   // Support for interprocedural escape analysis, from Thomas Kotzmann.
2010   enum EscapeFlag {
2011     estimated    = 1 << 0,
2012     return_local = 1 << 1,
2013     return_allocated = 1 << 2,
2014     allocated_escapes = 1 << 3,
2015     unknown_modified = 1 << 4
2016   };
2017 
2018   intx eflags()                                  { return _eflags; }
2019   intx arg_local()                               { return _arg_local; }
2020   intx arg_stack()                               { return _arg_stack; }
2021   intx arg_returned()                            { return _arg_returned; }
2022   uint arg_modified(int a)                       { ArgInfoData *aid = arg_info();
2023                                                    assert(aid != NULL, "arg_info must be not null");
2024                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
2025                                                    return aid->arg_modified(a); }
2026 
2027   void set_eflags(intx v)                        { _eflags = v; }
2028   void set_arg_local(intx v)                     { _arg_local = v; }
2029   void set_arg_stack(intx v)                     { _arg_stack = v; }
2030   void set_arg_returned(intx v)                  { _arg_returned = v; }
2031   void set_arg_modified(int a, uint v)           { ArgInfoData *aid = arg_info();
2032                                                    assert(aid != NULL, "arg_info must be not null");
2033                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
2034                                                    aid->set_arg_modified(a, v); }
2035 
2036   void clear_escape_info()                       { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
2037 
2038   // Location and size of data area
2039   address data_base() const {
2040     return (address) _data;
2041   }
2042   int data_size() const {
2043     return _data_size;
2044   }
2045 
2046   // Accessors
2047   Method* method() const { return _method; }
2048 
2049   // Get the data at an arbitrary (sort of) data index.
2050   ProfileData* data_at(int data_index) const;
2051 
2052   // Walk through the data in order.
2053   ProfileData* first_data() const { return data_at(first_di()); }
2054   ProfileData* next_data(ProfileData* current) const;
2055   bool is_valid(ProfileData* current) const { return current != NULL; }
2056 
2057   // Convert a dp (data pointer) to a di (data index).
2058   int dp_to_di(address dp) const {
2059     return dp - ((address)_data);
2060   }
2061 
2062   address di_to_dp(int di) {
2063     return (address)data_layout_at(di);
2064   }
2065 
2066   // bci to di/dp conversion.
2067   address bci_to_dp(int bci);
2068   int bci_to_di(int bci) {
2069     return dp_to_di(bci_to_dp(bci));
2070   }
2071 
2072   // Get the data at an arbitrary bci, or NULL if there is none.
2073   ProfileData* bci_to_data(int bci);
2074 
2075   // Same, but try to create an extra_data record if one is needed:
2076   ProfileData* allocate_bci_to_data(int bci) {
2077     ProfileData* data = bci_to_data(bci);
2078     return (data != NULL) ? data : bci_to_extra_data(bci, true);
2079   }
2080 
2081   // Add a handful of extra data records, for trap tracking.
2082   DataLayout* extra_data_base() const { return limit_data_position(); }
2083   DataLayout* extra_data_limit() const { return (DataLayout*)((address)this + size_in_bytes()); }
2084   int extra_data_size() const { return (address)extra_data_limit()
2085                                - (address)extra_data_base(); }
2086   static DataLayout* next_extra(DataLayout* dp) { return (DataLayout*)((address)dp + in_bytes(DataLayout::cell_offset(0))); }
2087 
2088   // Return (uint)-1 for overflow.
2089   uint trap_count(int reason) const {
2090     assert((uint)reason < _trap_hist_limit, "oob");
2091     return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
2092   }
2093   // For loops:
2094   static uint trap_reason_limit() { return _trap_hist_limit; }
2095   static uint trap_count_limit()  { return _trap_hist_mask; }
2096   uint inc_trap_count(int reason) {
2097     // Count another trap, anywhere in this method.
2098     assert(reason >= 0, "must be single trap");
2099     if ((uint)reason < _trap_hist_limit) {
2100       uint cnt1 = 1 + _trap_hist._array[reason];
2101       if ((cnt1 & _trap_hist_mask) != 0) {  // if no counter overflow...
2102         _trap_hist._array[reason] = cnt1;
2103         return cnt1;
2104       } else {
2105         return _trap_hist_mask + (++_nof_overflow_traps);
2106       }
2107     } else {
2108       // Could not represent the count in the histogram.
2109       return (++_nof_overflow_traps);
2110     }
2111   }
2112 
2113   uint overflow_trap_count() const {
2114     return _nof_overflow_traps;
2115   }
2116   uint overflow_recompile_count() const {
2117     return _nof_overflow_recompiles;
2118   }
2119   void inc_overflow_recompile_count() {
2120     _nof_overflow_recompiles += 1;
2121   }
2122   uint decompile_count() const {
2123     return _nof_decompiles;
2124   }
2125   void inc_decompile_count() {
2126     _nof_decompiles += 1;
2127     if (decompile_count() > (uint)PerMethodRecompilationCutoff) {
2128       method()->set_not_compilable(CompLevel_full_optimization, true, "decompile_count > PerMethodRecompilationCutoff");
2129     }
2130   }
2131 
2132   // Return pointer to area dedicated to parameters in MDO
2133   ParametersTypeData* parameters_type_data() const {
2134     return _parameters_type_data_di != -1 ? data_layout_at(_parameters_type_data_di)->data_in()->as_ParametersTypeData() : NULL;
2135   }
2136 
2137   int parameters_type_data_di() const {
2138     assert(_parameters_type_data_di != -1, "no args type data");
2139     return _parameters_type_data_di;
2140   }
2141 
2142   // Support for code generation
2143   static ByteSize data_offset() {
2144     return byte_offset_of(MethodData, _data[0]);
2145   }
2146 
2147   static ByteSize invocation_counter_offset() {
2148     return byte_offset_of(MethodData, _invocation_counter);
2149   }
2150   static ByteSize backedge_counter_offset() {
2151     return byte_offset_of(MethodData, _backedge_counter);
2152   }
2153 
2154   static ByteSize parameters_type_data_di_offset() {
2155     return byte_offset_of(MethodData, _parameters_type_data_di);
2156   }
2157 
2158   // Deallocation support - no pointer fields to deallocate
2159   void deallocate_contents(ClassLoaderData* loader_data) {}
2160 
2161   // GC support
2162   void set_size(int object_size_in_bytes) { _size = object_size_in_bytes; }
2163 
2164   // Printing
2165 #ifndef PRODUCT
2166   void print_on      (outputStream* st) const;
2167 #endif
2168   void print_value_on(outputStream* st) const;
2169 
2170 #ifndef PRODUCT
2171   // printing support for method data
2172   void print_data_on(outputStream* st) const;
2173 #endif
2174 
2175   const char* internal_name() const { return "{method data}"; }
2176 
2177   // verification
2178   void verify_on(outputStream* st);
2179   void verify_data_on(outputStream* st);
2180 
2181   static bool profile_parameters_for_method(methodHandle m);
2182   static bool profile_arguments();
2183   static bool profile_return();
2184   static bool profile_parameters();
2185   static bool profile_return_jsr292_only();
2186 };
2187 
2188 #endif // SHARE_VM_OOPS_METHODDATAOOP_HPP