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  *
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
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  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     speculative_trap_data_tag
 125   };
 126 
 127   enum {
 128     // The _struct._flags word is formatted as [trap_state:4 | flags:4].
 129     // The trap state breaks down further as [recompile:1 | reason:3].
 130     // This further breakdown is defined in deoptimization.cpp.
 131     // See Deoptimization::trap_state_reason for an assert that
 132     // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
 133     //
 134     // The trap_state is collected only if ProfileTraps is true.
 135     trap_bits = 1+3,  // 3: enough to distinguish [0..Reason_RECORDED_LIMIT].
 136     trap_shift = BitsPerByte - trap_bits,
 137     trap_mask = right_n_bits(trap_bits),
 138     trap_mask_in_place = (trap_mask << trap_shift),
 139     flag_limit = trap_shift,
 140     flag_mask = right_n_bits(flag_limit),
 141     first_flag = 0
 142   };
 143 
 144   // Size computation
 145   static int header_size_in_bytes() {
 146     return cell_size;
 147   }
 148   static int header_size_in_cells() {
 149     return 1;
 150   }
 151 
 152   static int compute_size_in_bytes(int cell_count) {
 153     return header_size_in_bytes() + cell_count * cell_size;
 154   }
 155 
 156   // Initialization
 157   void initialize(u1 tag, u2 bci, int cell_count);
 158 
 159   // Accessors
 160   u1 tag() {
 161     return _header._struct._tag;
 162   }
 163 
 164   // Return a few bits of trap state.  Range is [0..trap_mask].
 165   // The state tells if traps with zero, one, or many reasons have occurred.
 166   // It also tells whether zero or many recompilations have occurred.
 167   // The associated trap histogram in the MDO itself tells whether
 168   // traps are common or not.  If a BCI shows that a trap X has
 169   // occurred, and the MDO shows N occurrences of X, we make the
 170   // simplifying assumption that all N occurrences can be blamed
 171   // on that BCI.
 172   int trap_state() const {
 173     return ((_header._struct._flags >> trap_shift) & trap_mask);
 174   }
 175 
 176   void set_trap_state(int new_state) {
 177     assert(ProfileTraps, "used only under +ProfileTraps");
 178     uint old_flags = (_header._struct._flags & flag_mask);
 179     _header._struct._flags = (new_state << trap_shift) | old_flags;
 180   }
 181 
 182   u1 flags() const {
 183     return _header._struct._flags;
 184   }
 185 
 186   u2 bci() const {
 187     return _header._struct._bci;
 188   }
 189 
 190   void set_header(intptr_t value) {
 191     _header._bits = value;
 192   }
 193   intptr_t header() {
 194     return _header._bits;
 195   }
 196   void set_cell_at(int index, intptr_t value) {
 197     _cells[index] = value;
 198   }
 199   void release_set_cell_at(int index, intptr_t value) {
 200     OrderAccess::release_store_ptr(&_cells[index], value);
 201   }
 202   intptr_t cell_at(int index) const {
 203     return _cells[index];
 204   }
 205 
 206   void set_flag_at(int flag_number) {
 207     assert(flag_number < flag_limit, "oob");
 208     _header._struct._flags |= (0x1 << flag_number);
 209   }
 210   bool flag_at(int flag_number) const {
 211     assert(flag_number < flag_limit, "oob");
 212     return (_header._struct._flags & (0x1 << flag_number)) != 0;
 213   }
 214 
 215   // Low-level support for code generation.
 216   static ByteSize header_offset() {
 217     return byte_offset_of(DataLayout, _header);
 218   }
 219   static ByteSize tag_offset() {
 220     return byte_offset_of(DataLayout, _header._struct._tag);
 221   }
 222   static ByteSize flags_offset() {
 223     return byte_offset_of(DataLayout, _header._struct._flags);
 224   }
 225   static ByteSize bci_offset() {
 226     return byte_offset_of(DataLayout, _header._struct._bci);
 227   }
 228   static ByteSize cell_offset(int index) {
 229     return byte_offset_of(DataLayout, _cells) + in_ByteSize(index * cell_size);
 230   }
 231 #ifdef CC_INTERP
 232   static int cell_offset_in_bytes(int index) {
 233     return (int)offset_of(DataLayout, _cells[index]);
 234   }
 235 #endif // CC_INTERP
 236   // Return a value which, when or-ed as a byte into _flags, sets the flag.
 237   static int flag_number_to_byte_constant(int flag_number) {
 238     assert(0 <= flag_number && flag_number < flag_limit, "oob");
 239     DataLayout temp; temp.set_header(0);
 240     temp.set_flag_at(flag_number);
 241     return temp._header._struct._flags;
 242   }
 243   // Return a value which, when or-ed as a word into _header, sets the flag.
 244   static intptr_t flag_mask_to_header_mask(int byte_constant) {
 245     DataLayout temp; temp.set_header(0);
 246     temp._header._struct._flags = byte_constant;
 247     return temp._header._bits;
 248   }
 249 
 250   ProfileData* data_in();
 251 
 252   // GC support
 253   void clean_weak_klass_links(BoolObjectClosure* cl);
 254 };
 255 
 256 
 257 // ProfileData class hierarchy
 258 class ProfileData;
 259 class   BitData;
 260 class     CounterData;
 261 class       ReceiverTypeData;
 262 class         VirtualCallData;
 263 class           VirtualCallTypeData;
 264 class       RetData;
 265 class       CallTypeData;
 266 class   JumpData;
 267 class     BranchData;
 268 class   ArrayData;
 269 class     MultiBranchData;
 270 class     ArgInfoData;
 271 class     ParametersTypeData;
 272 class   SpeculativeTrapData;
 273 
 274 // ProfileData
 275 //
 276 // A ProfileData object is created to refer to a section of profiling
 277 // data in a structured way.
 278 class ProfileData : public ResourceObj {
 279   friend class TypeEntries;
 280   friend class ReturnTypeEntry;
 281   friend class TypeStackSlotEntries;
 282 private:
 283 #ifndef PRODUCT
 284   enum {
 285     tab_width_one = 16,
 286     tab_width_two = 36
 287   };
 288 #endif // !PRODUCT
 289 
 290   // This is a pointer to a section of profiling data.
 291   DataLayout* _data;
 292 
 293   char* print_data_on_helper(const MethodData* md) const;
 294 
 295 protected:
 296   DataLayout* data() { return _data; }
 297   const DataLayout* data() const { return _data; }
 298 
 299   enum {
 300     cell_size = DataLayout::cell_size
 301   };
 302 
 303 public:
 304   // How many cells are in this?
 305   virtual int cell_count() const {
 306     ShouldNotReachHere();
 307     return -1;
 308   }
 309 
 310   // Return the size of this data.
 311   int size_in_bytes() {
 312     return DataLayout::compute_size_in_bytes(cell_count());
 313   }
 314 
 315 protected:
 316   // Low-level accessors for underlying data
 317   void set_intptr_at(int index, intptr_t value) {
 318     assert(0 <= index && index < cell_count(), "oob");
 319     data()->set_cell_at(index, value);
 320   }
 321   void release_set_intptr_at(int index, intptr_t value) {
 322     assert(0 <= index && index < cell_count(), "oob");
 323     data()->release_set_cell_at(index, value);
 324   }
 325   intptr_t intptr_at(int index) const {
 326     assert(0 <= index && index < cell_count(), "oob");
 327     return data()->cell_at(index);
 328   }
 329   void set_uint_at(int index, uint value) {
 330     set_intptr_at(index, (intptr_t) value);
 331   }
 332   void release_set_uint_at(int index, uint value) {
 333     release_set_intptr_at(index, (intptr_t) value);
 334   }
 335   uint uint_at(int index) const {
 336     return (uint)intptr_at(index);
 337   }
 338   void set_int_at(int index, int value) {
 339     set_intptr_at(index, (intptr_t) value);
 340   }
 341   void release_set_int_at(int index, int value) {
 342     release_set_intptr_at(index, (intptr_t) value);
 343   }
 344   int int_at(int index) const {
 345     return (int)intptr_at(index);
 346   }
 347   int int_at_unchecked(int index) const {
 348     return (int)data()->cell_at(index);
 349   }
 350   void set_oop_at(int index, oop value) {
 351     set_intptr_at(index, cast_from_oop<intptr_t>(value));
 352   }
 353   oop oop_at(int index) const {
 354     return cast_to_oop(intptr_at(index));
 355   }
 356 
 357   void set_flag_at(int flag_number) {
 358     data()->set_flag_at(flag_number);
 359   }
 360   bool flag_at(int flag_number) const {
 361     return data()->flag_at(flag_number);
 362   }
 363 
 364   // two convenient imports for use by subclasses:
 365   static ByteSize cell_offset(int index) {
 366     return DataLayout::cell_offset(index);
 367   }
 368   static int flag_number_to_byte_constant(int flag_number) {
 369     return DataLayout::flag_number_to_byte_constant(flag_number);
 370   }
 371 
 372   ProfileData(DataLayout* data) {
 373     _data = data;
 374   }
 375 
 376 #ifdef CC_INTERP
 377   // Static low level accessors for DataLayout with ProfileData's semantics.
 378 
 379   static int cell_offset_in_bytes(int index) {
 380     return DataLayout::cell_offset_in_bytes(index);
 381   }
 382 
 383   static void increment_uint_at_no_overflow(DataLayout* layout, int index,
 384                                             int inc = DataLayout::counter_increment) {
 385     uint count = ((uint)layout->cell_at(index)) + inc;
 386     if (count == 0) return;
 387     layout->set_cell_at(index, (intptr_t) count);
 388   }
 389 
 390   static int int_at(DataLayout* layout, int index) {
 391     return (int)layout->cell_at(index);
 392   }
 393 
 394   static int uint_at(DataLayout* layout, int index) {
 395     return (uint)layout->cell_at(index);
 396   }
 397 
 398   static oop oop_at(DataLayout* layout, int index) {
 399     return cast_to_oop(layout->cell_at(index));
 400   }
 401 
 402   static void set_intptr_at(DataLayout* layout, int index, intptr_t value) {
 403     layout->set_cell_at(index, (intptr_t) value);
 404   }
 405 
 406   static void set_flag_at(DataLayout* layout, int flag_number) {
 407     layout->set_flag_at(flag_number);
 408   }
 409 #endif // CC_INTERP
 410 
 411 public:
 412   // Constructor for invalid ProfileData.
 413   ProfileData();
 414 
 415   u2 bci() const {
 416     return data()->bci();
 417   }
 418 
 419   address dp() {
 420     return (address)_data;
 421   }
 422 
 423   int trap_state() const {
 424     return data()->trap_state();
 425   }
 426   void set_trap_state(int new_state) {
 427     data()->set_trap_state(new_state);
 428   }
 429 
 430   // Type checking
 431   virtual bool is_BitData()         const { return false; }
 432   virtual bool is_CounterData()     const { return false; }
 433   virtual bool is_JumpData()        const { return false; }
 434   virtual bool is_ReceiverTypeData()const { return false; }
 435   virtual bool is_VirtualCallData() const { return false; }
 436   virtual bool is_RetData()         const { return false; }
 437   virtual bool is_BranchData()      const { return false; }
 438   virtual bool is_ArrayData()       const { return false; }
 439   virtual bool is_MultiBranchData() const { return false; }
 440   virtual bool is_ArgInfoData()     const { return false; }
 441   virtual bool is_CallTypeData()    const { return false; }
 442   virtual bool is_VirtualCallTypeData()const { return false; }
 443   virtual bool is_ParametersTypeData() const { return false; }
 444   virtual bool is_SpeculativeTrapData()const { return false; }
 445 
 446 
 447   BitData* as_BitData() const {
 448     assert(is_BitData(), "wrong type");
 449     return is_BitData()         ? (BitData*)        this : NULL;
 450   }
 451   CounterData* as_CounterData() const {
 452     assert(is_CounterData(), "wrong type");
 453     return is_CounterData()     ? (CounterData*)    this : NULL;
 454   }
 455   JumpData* as_JumpData() const {
 456     assert(is_JumpData(), "wrong type");
 457     return is_JumpData()        ? (JumpData*)       this : NULL;
 458   }
 459   ReceiverTypeData* as_ReceiverTypeData() const {
 460     assert(is_ReceiverTypeData(), "wrong type");
 461     return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
 462   }
 463   VirtualCallData* as_VirtualCallData() const {
 464     assert(is_VirtualCallData(), "wrong type");
 465     return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
 466   }
 467   RetData* as_RetData() const {
 468     assert(is_RetData(), "wrong type");
 469     return is_RetData()         ? (RetData*)        this : NULL;
 470   }
 471   BranchData* as_BranchData() const {
 472     assert(is_BranchData(), "wrong type");
 473     return is_BranchData()      ? (BranchData*)     this : NULL;
 474   }
 475   ArrayData* as_ArrayData() const {
 476     assert(is_ArrayData(), "wrong type");
 477     return is_ArrayData()       ? (ArrayData*)      this : NULL;
 478   }
 479   MultiBranchData* as_MultiBranchData() const {
 480     assert(is_MultiBranchData(), "wrong type");
 481     return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
 482   }
 483   ArgInfoData* as_ArgInfoData() const {
 484     assert(is_ArgInfoData(), "wrong type");
 485     return is_ArgInfoData() ? (ArgInfoData*)this : NULL;
 486   }
 487   CallTypeData* as_CallTypeData() const {
 488     assert(is_CallTypeData(), "wrong type");
 489     return is_CallTypeData() ? (CallTypeData*)this : NULL;
 490   }
 491   VirtualCallTypeData* as_VirtualCallTypeData() const {
 492     assert(is_VirtualCallTypeData(), "wrong type");
 493     return is_VirtualCallTypeData() ? (VirtualCallTypeData*)this : NULL;
 494   }
 495   ParametersTypeData* as_ParametersTypeData() const {
 496     assert(is_ParametersTypeData(), "wrong type");
 497     return is_ParametersTypeData() ? (ParametersTypeData*)this : NULL;
 498   }
 499   SpeculativeTrapData* as_SpeculativeTrapData() const {
 500     assert(is_SpeculativeTrapData(), "wrong type");
 501     return is_SpeculativeTrapData() ? (SpeculativeTrapData*)this : NULL;
 502   }
 503 
 504 
 505   // Subclass specific initialization
 506   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo) {}
 507 
 508   // GC support
 509   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {}
 510 
 511   // CI translation: ProfileData can represent both MethodDataOop data
 512   // as well as CIMethodData data. This function is provided for translating
 513   // an oop in a ProfileData to the ci equivalent. Generally speaking,
 514   // most ProfileData don't require any translation, so we provide the null
 515   // translation here, and the required translators are in the ci subclasses.
 516   virtual void translate_from(const ProfileData* data) {}
 517 
 518   virtual void print_data_on(outputStream* st, const char* extra = NULL) const {
 519     ShouldNotReachHere();
 520   }
 521 
 522   void print_data_on(outputStream* st, const MethodData* md) const;
 523 
 524 #ifndef PRODUCT
 525   void print_shared(outputStream* st, const char* name, const char* extra) const;
 526   void tab(outputStream* st, bool first = false) const;
 527 #endif
 528 };
 529 
 530 // BitData
 531 //
 532 // A BitData holds a flag or two in its header.
 533 class BitData : public ProfileData {
 534 protected:
 535   enum {
 536     // null_seen:
 537     //  saw a null operand (cast/aastore/instanceof)
 538     null_seen_flag              = DataLayout::first_flag + 0
 539   };
 540   enum { bit_cell_count = 0 };  // no additional data fields needed.
 541 public:
 542   BitData(DataLayout* layout) : ProfileData(layout) {
 543   }
 544 
 545   virtual bool is_BitData() const { return true; }
 546 
 547   static int static_cell_count() {
 548     return bit_cell_count;
 549   }
 550 
 551   virtual int cell_count() const {
 552     return static_cell_count();
 553   }
 554 
 555   // Accessor
 556 
 557   // The null_seen flag bit is specially known to the interpreter.
 558   // Consulting it allows the compiler to avoid setting up null_check traps.
 559   bool null_seen()     { return flag_at(null_seen_flag); }
 560   void set_null_seen()    { set_flag_at(null_seen_flag); }
 561 
 562 
 563   // Code generation support
 564   static int null_seen_byte_constant() {
 565     return flag_number_to_byte_constant(null_seen_flag);
 566   }
 567 
 568   static ByteSize bit_data_size() {
 569     return cell_offset(bit_cell_count);
 570   }
 571 
 572 #ifdef CC_INTERP
 573   static int bit_data_size_in_bytes() {
 574     return cell_offset_in_bytes(bit_cell_count);
 575   }
 576 
 577   static void set_null_seen(DataLayout* layout) {
 578     set_flag_at(layout, null_seen_flag);
 579   }
 580 
 581   static DataLayout* advance(DataLayout* layout) {
 582     return (DataLayout*) (((address)layout) + (ssize_t)BitData::bit_data_size_in_bytes());
 583   }
 584 #endif // CC_INTERP
 585 
 586 #ifndef PRODUCT
 587   void print_data_on(outputStream* st, const char* extra = NULL) const;
 588 #endif
 589 };
 590 
 591 // CounterData
 592 //
 593 // A CounterData corresponds to a simple counter.
 594 class CounterData : public BitData {
 595 protected:
 596   enum {
 597     count_off,
 598     counter_cell_count
 599   };
 600 public:
 601   CounterData(DataLayout* layout) : BitData(layout) {}
 602 
 603   virtual bool is_CounterData() const { return true; }
 604 
 605   static int static_cell_count() {
 606     return counter_cell_count;
 607   }
 608 
 609   virtual int cell_count() const {
 610     return static_cell_count();
 611   }
 612 
 613   // Direct accessor
 614   uint count() const {
 615     return uint_at(count_off);
 616   }
 617 
 618   // Code generation support
 619   static ByteSize count_offset() {
 620     return cell_offset(count_off);
 621   }
 622   static ByteSize counter_data_size() {
 623     return cell_offset(counter_cell_count);
 624   }
 625 
 626   void set_count(uint count) {
 627     set_uint_at(count_off, count);
 628   }
 629 
 630 #ifdef CC_INTERP
 631   static int counter_data_size_in_bytes() {
 632     return cell_offset_in_bytes(counter_cell_count);
 633   }
 634 
 635   static void increment_count_no_overflow(DataLayout* layout) {
 636     increment_uint_at_no_overflow(layout, count_off);
 637   }
 638 
 639   // Support counter decrementation at checkcast / subtype check failed.
 640   static void decrement_count(DataLayout* layout) {
 641     increment_uint_at_no_overflow(layout, count_off, -1);
 642   }
 643 
 644   static DataLayout* advance(DataLayout* layout) {
 645     return (DataLayout*) (((address)layout) + (ssize_t)CounterData::counter_data_size_in_bytes());
 646   }
 647 #endif // CC_INTERP
 648 
 649 #ifndef PRODUCT
 650   void print_data_on(outputStream* st, const char* extra = NULL) const;
 651 #endif
 652 };
 653 
 654 // JumpData
 655 //
 656 // A JumpData is used to access profiling information for a direct
 657 // branch.  It is a counter, used for counting the number of branches,
 658 // plus a data displacement, used for realigning the data pointer to
 659 // the corresponding target bci.
 660 class JumpData : public ProfileData {
 661 protected:
 662   enum {
 663     taken_off_set,
 664     displacement_off_set,
 665     jump_cell_count
 666   };
 667 
 668   void set_displacement(int displacement) {
 669     set_int_at(displacement_off_set, displacement);
 670   }
 671 
 672 public:
 673   JumpData(DataLayout* layout) : ProfileData(layout) {
 674     assert(layout->tag() == DataLayout::jump_data_tag ||
 675       layout->tag() == DataLayout::branch_data_tag, "wrong type");
 676   }
 677 
 678   virtual bool is_JumpData() const { return true; }
 679 
 680   static int static_cell_count() {
 681     return jump_cell_count;
 682   }
 683 
 684   virtual int cell_count() const {
 685     return static_cell_count();
 686   }
 687 
 688   // Direct accessor
 689   uint taken() const {
 690     return uint_at(taken_off_set);
 691   }
 692 
 693   void set_taken(uint cnt) {
 694     set_uint_at(taken_off_set, cnt);
 695   }
 696 
 697   // Saturating counter
 698   uint inc_taken() {
 699     uint cnt = taken() + 1;
 700     // Did we wrap? Will compiler screw us??
 701     if (cnt == 0) cnt--;
 702     set_uint_at(taken_off_set, cnt);
 703     return cnt;
 704   }
 705 
 706   int displacement() const {
 707     return int_at(displacement_off_set);
 708   }
 709 
 710   // Code generation support
 711   static ByteSize taken_offset() {
 712     return cell_offset(taken_off_set);
 713   }
 714 
 715   static ByteSize displacement_offset() {
 716     return cell_offset(displacement_off_set);
 717   }
 718 
 719 #ifdef CC_INTERP
 720   static void increment_taken_count_no_overflow(DataLayout* layout) {
 721     increment_uint_at_no_overflow(layout, taken_off_set);
 722   }
 723 
 724   static DataLayout* advance_taken(DataLayout* layout) {
 725     return (DataLayout*) (((address)layout) + (ssize_t)int_at(layout, displacement_off_set));
 726   }
 727 
 728   static uint taken_count(DataLayout* layout) {
 729     return (uint) uint_at(layout, taken_off_set);
 730   }
 731 #endif // CC_INTERP
 732 
 733   // Specific initialization.
 734   void post_initialize(BytecodeStream* stream, MethodData* mdo);
 735 
 736 #ifndef PRODUCT
 737   void print_data_on(outputStream* st, const char* extra = NULL) const;
 738 #endif
 739 };
 740 
 741 // Entries in a ProfileData object to record types: it can either be
 742 // none (no profile), unknown (conflicting profile data) or a klass if
 743 // a single one is seen. Whether a null reference was seen is also
 744 // recorded. No counter is associated with the type and a single type
 745 // is tracked (unlike VirtualCallData).
 746 class TypeEntries {
 747 
 748 public:
 749 
 750   // A single cell is used to record information for a type:
 751   // - the cell is initialized to 0
 752   // - when a type is discovered it is stored in the cell
 753   // - bit zero of the cell is used to record whether a null reference
 754   // was encountered or not
 755   // - bit 1 is set to record a conflict in the type information
 756 
 757   enum {
 758     null_seen = 1,
 759     type_mask = ~null_seen,
 760     type_unknown = 2,
 761     status_bits = null_seen | type_unknown,
 762     type_klass_mask = ~status_bits
 763   };
 764 
 765   // what to initialize a cell to
 766   static intptr_t type_none() {
 767     return 0;
 768   }
 769 
 770   // null seen = bit 0 set?
 771   static bool was_null_seen(intptr_t v) {
 772     return (v & null_seen) != 0;
 773   }
 774 
 775   // conflicting type information = bit 1 set?
 776   static bool is_type_unknown(intptr_t v) {
 777     return (v & type_unknown) != 0;
 778   }
 779 
 780   // not type information yet = all bits cleared, ignoring bit 0?
 781   static bool is_type_none(intptr_t v) {
 782     return (v & type_mask) == 0;
 783   }
 784 
 785   // recorded type: cell without bit 0 and 1
 786   static intptr_t klass_part(intptr_t v) {
 787     intptr_t r = v & type_klass_mask;
 788     return r;
 789   }
 790 
 791   // type recorded
 792   static Klass* valid_klass(intptr_t k) {
 793     if (!is_type_none(k) &&
 794         !is_type_unknown(k)) {
 795       Klass* res = (Klass*)klass_part(k);
 796       assert(res != NULL, "invalid");
 797       return res;
 798     } else {
 799       return NULL;
 800     }
 801   }
 802 
 803   static intptr_t with_status(intptr_t k, intptr_t in) {
 804     return k | (in & status_bits);
 805   }
 806 
 807   static intptr_t with_status(Klass* k, intptr_t in) {
 808     return with_status((intptr_t)k, in);
 809   }
 810 
 811 #ifndef PRODUCT
 812   static void print_klass(outputStream* st, intptr_t k);
 813 #endif
 814 
 815   // GC support
 816   static bool is_loader_alive(BoolObjectClosure* is_alive_cl, intptr_t p);
 817 
 818 protected:
 819   // ProfileData object these entries are part of
 820   ProfileData* _pd;
 821   // offset within the ProfileData object where the entries start
 822   const int _base_off;
 823 
 824   TypeEntries(int base_off)
 825     : _base_off(base_off), _pd(NULL) {}
 826 
 827   void set_intptr_at(int index, intptr_t value) {
 828     _pd->set_intptr_at(index, value);
 829   }
 830 
 831   intptr_t intptr_at(int index) const {
 832     return _pd->intptr_at(index);
 833   }
 834 
 835 public:
 836   void set_profile_data(ProfileData* pd) {
 837     _pd = pd;
 838   }
 839 };
 840 
 841 // Type entries used for arguments passed at a call and parameters on
 842 // method entry. 2 cells per entry: one for the type encoded as in
 843 // TypeEntries and one initialized with the stack slot where the
 844 // profiled object is to be found so that the interpreter can locate
 845 // it quickly.
 846 class TypeStackSlotEntries : public TypeEntries {
 847 
 848 private:
 849   enum {
 850     stack_slot_entry,
 851     type_entry,
 852     per_arg_cell_count
 853   };
 854 
 855   // offset of cell for stack slot for entry i within ProfileData object
 856   int stack_slot_offset(int i) const {
 857     return _base_off + stack_slot_local_offset(i);
 858   }
 859 
 860 protected:
 861   const int _number_of_entries;
 862 
 863   // offset of cell for type for entry i within ProfileData object
 864   int type_offset(int i) const {
 865     return _base_off + type_local_offset(i);
 866   }
 867 
 868 public:
 869 
 870   TypeStackSlotEntries(int base_off, int nb_entries)
 871     : TypeEntries(base_off), _number_of_entries(nb_entries) {}
 872 
 873   static int compute_cell_count(Symbol* signature, bool include_receiver, int max);
 874 
 875   void post_initialize(Symbol* signature, bool has_receiver, bool include_receiver);
 876 
 877   // offset of cell for stack slot for entry i within this block of cells for a TypeStackSlotEntries
 878   static int stack_slot_local_offset(int i) {
 879     return i * per_arg_cell_count + stack_slot_entry;
 880   }
 881 
 882   // offset of cell for type for entry i within this block of cells for a TypeStackSlotEntries
 883   static int type_local_offset(int i) {
 884     return i * per_arg_cell_count + type_entry;
 885   }
 886 
 887   // stack slot for entry i
 888   uint stack_slot(int i) const {
 889     assert(i >= 0 && i < _number_of_entries, "oob");
 890     return _pd->uint_at(stack_slot_offset(i));
 891   }
 892 
 893   // set stack slot for entry i
 894   void set_stack_slot(int i, uint num) {
 895     assert(i >= 0 && i < _number_of_entries, "oob");
 896     _pd->set_uint_at(stack_slot_offset(i), num);
 897   }
 898 
 899   // type for entry i
 900   intptr_t type(int i) const {
 901     assert(i >= 0 && i < _number_of_entries, "oob");
 902     return _pd->intptr_at(type_offset(i));
 903   }
 904 
 905   // set type for entry i
 906   void set_type(int i, intptr_t k) {
 907     assert(i >= 0 && i < _number_of_entries, "oob");
 908     _pd->set_intptr_at(type_offset(i), k);
 909   }
 910 
 911   static ByteSize per_arg_size() {
 912     return in_ByteSize(per_arg_cell_count * DataLayout::cell_size);
 913   }
 914 
 915   static int per_arg_count() {
 916     return per_arg_cell_count ;
 917   }
 918 
 919   // GC support
 920   void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
 921 
 922 #ifndef PRODUCT
 923   void print_data_on(outputStream* st) const;
 924 #endif
 925 };
 926 
 927 // Type entry used for return from a call. A single cell to record the
 928 // type.
 929 class ReturnTypeEntry : public TypeEntries {
 930 
 931 private:
 932   enum {
 933     cell_count = 1
 934   };
 935 
 936 public:
 937   ReturnTypeEntry(int base_off)
 938     : TypeEntries(base_off) {}
 939 
 940   void post_initialize() {
 941     set_type(type_none());
 942   }
 943 
 944   intptr_t type() const {
 945     return _pd->intptr_at(_base_off);
 946   }
 947 
 948   void set_type(intptr_t k) {
 949     _pd->set_intptr_at(_base_off, k);
 950   }
 951 
 952   static int static_cell_count() {
 953     return cell_count;
 954   }
 955 
 956   static ByteSize size() {
 957     return in_ByteSize(cell_count * DataLayout::cell_size);
 958   }
 959 
 960   ByteSize type_offset() {
 961     return DataLayout::cell_offset(_base_off);
 962   }
 963 
 964   // GC support
 965   void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
 966 
 967 #ifndef PRODUCT
 968   void print_data_on(outputStream* st) const;
 969 #endif
 970 };
 971 
 972 // Entries to collect type information at a call: contains arguments
 973 // (TypeStackSlotEntries), a return type (ReturnTypeEntry) and a
 974 // number of cells. Because the number of cells for the return type is
 975 // smaller than the number of cells for the type of an arguments, the
 976 // number of cells is used to tell how many arguments are profiled and
 977 // whether a return value is profiled. See has_arguments() and
 978 // has_return().
 979 class TypeEntriesAtCall {
 980 private:
 981   static int stack_slot_local_offset(int i) {
 982     return header_cell_count() + TypeStackSlotEntries::stack_slot_local_offset(i);
 983   }
 984 
 985   static int argument_type_local_offset(int i) {
 986     return header_cell_count() + TypeStackSlotEntries::type_local_offset(i);;
 987   }
 988 
 989 public:
 990 
 991   static int header_cell_count() {
 992     return 1;
 993   }
 994 
 995   static int cell_count_local_offset() {
 996     return 0;
 997   }
 998 
 999   static int compute_cell_count(BytecodeStream* stream);
1000 
1001   static void initialize(DataLayout* dl, int base, int cell_count) {
1002     int off = base + cell_count_local_offset();
1003     dl->set_cell_at(off, cell_count - base - header_cell_count());
1004   }
1005 
1006   static bool arguments_profiling_enabled();
1007   static bool return_profiling_enabled();
1008 
1009   // Code generation support
1010   static ByteSize cell_count_offset() {
1011     return in_ByteSize(cell_count_local_offset() * DataLayout::cell_size);
1012   }
1013 
1014   static ByteSize args_data_offset() {
1015     return in_ByteSize(header_cell_count() * DataLayout::cell_size);
1016   }
1017 
1018   static ByteSize stack_slot_offset(int i) {
1019     return in_ByteSize(stack_slot_local_offset(i) * DataLayout::cell_size);
1020   }
1021 
1022   static ByteSize argument_type_offset(int i) {
1023     return in_ByteSize(argument_type_local_offset(i) * DataLayout::cell_size);
1024   }
1025 };
1026 
1027 // CallTypeData
1028 //
1029 // A CallTypeData is used to access profiling information about a non
1030 // virtual call for which we collect type information about arguments
1031 // and return value.
1032 class CallTypeData : public CounterData {
1033 private:
1034   // entries for arguments if any
1035   TypeStackSlotEntries _args;
1036   // entry for return type if any
1037   ReturnTypeEntry _ret;
1038 
1039   int cell_count_global_offset() const {
1040     return CounterData::static_cell_count() + TypeEntriesAtCall::cell_count_local_offset();
1041   }
1042 
1043   // number of cells not counting the header
1044   int cell_count_no_header() const {
1045     return uint_at(cell_count_global_offset());
1046   }
1047 
1048   void check_number_of_arguments(int total) {
1049     assert(number_of_arguments() == total, "should be set in DataLayout::initialize");
1050   }
1051 
1052 public:
1053   CallTypeData(DataLayout* layout) :
1054     CounterData(layout),
1055     _args(CounterData::static_cell_count()+TypeEntriesAtCall::header_cell_count(), number_of_arguments()),
1056     _ret(cell_count() - ReturnTypeEntry::static_cell_count())
1057   {
1058     assert(layout->tag() == DataLayout::call_type_data_tag, "wrong type");
1059     // Some compilers (VC++) don't want this passed in member initialization list
1060     _args.set_profile_data(this);
1061     _ret.set_profile_data(this);
1062   }
1063 
1064   const TypeStackSlotEntries* args() const {
1065     assert(has_arguments(), "no profiling of arguments");
1066     return &_args;
1067   }
1068 
1069   const ReturnTypeEntry* ret() const {
1070     assert(has_return(), "no profiling of return value");
1071     return &_ret;
1072   }
1073 
1074   virtual bool is_CallTypeData() const { return true; }
1075 
1076   static int static_cell_count() {
1077     return -1;
1078   }
1079 
1080   static int compute_cell_count(BytecodeStream* stream) {
1081     return CounterData::static_cell_count() + TypeEntriesAtCall::compute_cell_count(stream);
1082   }
1083 
1084   static void initialize(DataLayout* dl, int cell_count) {
1085     TypeEntriesAtCall::initialize(dl, CounterData::static_cell_count(), cell_count);
1086   }
1087 
1088   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1089 
1090   virtual int cell_count() const {
1091     return CounterData::static_cell_count() +
1092       TypeEntriesAtCall::header_cell_count() +
1093       int_at_unchecked(cell_count_global_offset());
1094   }
1095 
1096   int number_of_arguments() const {
1097     return cell_count_no_header() / TypeStackSlotEntries::per_arg_count();
1098   }
1099 
1100   void set_argument_type(int i, Klass* k) {
1101     assert(has_arguments(), "no arguments!");
1102     intptr_t current = _args.type(i);
1103     _args.set_type(i, TypeEntries::with_status(k, current));
1104   }
1105 
1106   void set_return_type(Klass* k) {
1107     assert(has_return(), "no return!");
1108     intptr_t current = _ret.type();
1109     _ret.set_type(TypeEntries::with_status(k, current));
1110   }
1111 
1112   // An entry for a return value takes less space than an entry for an
1113   // argument so if the number of cells exceeds the number of cells
1114   // needed for an argument, this object contains type information for
1115   // at least one argument.
1116   bool has_arguments() const {
1117     bool res = cell_count_no_header() >= TypeStackSlotEntries::per_arg_count();
1118     assert (!res || TypeEntriesAtCall::arguments_profiling_enabled(), "no profiling of arguments");
1119     return res;
1120   }
1121 
1122   // An entry for a return value takes less space than an entry for an
1123   // argument, so if the remainder of the number of cells divided by
1124   // the number of cells for an argument is not null, a return value
1125   // is profiled in this object.
1126   bool has_return() const {
1127     bool res = (cell_count_no_header() % TypeStackSlotEntries::per_arg_count()) != 0;
1128     assert (!res || TypeEntriesAtCall::return_profiling_enabled(), "no profiling of return values");
1129     return res;
1130   }
1131 
1132   // Code generation support
1133   static ByteSize args_data_offset() {
1134     return cell_offset(CounterData::static_cell_count()) + TypeEntriesAtCall::args_data_offset();
1135   }
1136 
1137   // GC support
1138   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {
1139     if (has_arguments()) {
1140       _args.clean_weak_klass_links(is_alive_closure);
1141     }
1142     if (has_return()) {
1143       _ret.clean_weak_klass_links(is_alive_closure);
1144     }
1145   }
1146 
1147 #ifndef PRODUCT
1148   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1149 #endif
1150 };
1151 
1152 // ReceiverTypeData
1153 //
1154 // A ReceiverTypeData is used to access profiling information about a
1155 // dynamic type check.  It consists of a counter which counts the total times
1156 // that the check is reached, and a series of (Klass*, count) pairs
1157 // which are used to store a type profile for the receiver of the check.
1158 class ReceiverTypeData : public CounterData {
1159 protected:
1160   enum {
1161     receiver0_offset = counter_cell_count,
1162     count0_offset,
1163     receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
1164   };
1165 
1166 public:
1167   ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
1168     assert(layout->tag() == DataLayout::receiver_type_data_tag ||
1169            layout->tag() == DataLayout::virtual_call_data_tag ||
1170            layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1171   }
1172 
1173   virtual bool is_ReceiverTypeData() const { return true; }
1174 
1175   static int static_cell_count() {
1176     return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count;
1177   }
1178 
1179   virtual int cell_count() const {
1180     return static_cell_count();
1181   }
1182 
1183   // Direct accessors
1184   static uint row_limit() {
1185     return TypeProfileWidth;
1186   }
1187   static int receiver_cell_index(uint row) {
1188     return receiver0_offset + row * receiver_type_row_cell_count;
1189   }
1190   static int receiver_count_cell_index(uint row) {
1191     return count0_offset + row * receiver_type_row_cell_count;
1192   }
1193 
1194   Klass* receiver(uint row) const {
1195     assert(row < row_limit(), "oob");
1196 
1197     Klass* recv = (Klass*)intptr_at(receiver_cell_index(row));
1198     assert(recv == NULL || recv->is_klass(), "wrong type");
1199     return recv;
1200   }
1201 
1202   void set_receiver(uint row, Klass* k) {
1203     assert((uint)row < row_limit(), "oob");
1204     set_intptr_at(receiver_cell_index(row), (uintptr_t)k);
1205   }
1206 
1207   uint receiver_count(uint row) const {
1208     assert(row < row_limit(), "oob");
1209     return uint_at(receiver_count_cell_index(row));
1210   }
1211 
1212   void set_receiver_count(uint row, uint count) {
1213     assert(row < row_limit(), "oob");
1214     set_uint_at(receiver_count_cell_index(row), count);
1215   }
1216 
1217   void clear_row(uint row) {
1218     assert(row < row_limit(), "oob");
1219     // Clear total count - indicator of polymorphic call site.
1220     // The site may look like as monomorphic after that but
1221     // it allow to have more accurate profiling information because
1222     // there was execution phase change since klasses were unloaded.
1223     // If the site is still polymorphic then MDO will be updated
1224     // to reflect it. But it could be the case that the site becomes
1225     // only bimorphic. Then keeping total count not 0 will be wrong.
1226     // Even if we use monomorphic (when it is not) for compilation
1227     // we will only have trap, deoptimization and recompile again
1228     // with updated MDO after executing method in Interpreter.
1229     // An additional receiver will be recorded in the cleaned row
1230     // during next call execution.
1231     //
1232     // Note: our profiling logic works with empty rows in any slot.
1233     // We do sorting a profiling info (ciCallProfile) for compilation.
1234     //
1235     set_count(0);
1236     set_receiver(row, NULL);
1237     set_receiver_count(row, 0);
1238   }
1239 
1240   // Code generation support
1241   static ByteSize receiver_offset(uint row) {
1242     return cell_offset(receiver_cell_index(row));
1243   }
1244   static ByteSize receiver_count_offset(uint row) {
1245     return cell_offset(receiver_count_cell_index(row));
1246   }
1247   static ByteSize receiver_type_data_size() {
1248     return cell_offset(static_cell_count());
1249   }
1250 
1251   // GC support
1252   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
1253 
1254 #ifdef CC_INTERP
1255   static int receiver_type_data_size_in_bytes() {
1256     return cell_offset_in_bytes(static_cell_count());
1257   }
1258 
1259   static Klass *receiver_unchecked(DataLayout* layout, uint row) {
1260     Klass* recv = (Klass*)layout->cell_at(receiver_cell_index(row));
1261     return recv;
1262   }
1263 
1264   static void increment_receiver_count_no_overflow(DataLayout* layout, Klass *rcvr) {
1265     const int num_rows = row_limit();
1266     // Receiver already exists?
1267     for (int row = 0; row < num_rows; row++) {
1268       if (receiver_unchecked(layout, row) == rcvr) {
1269         increment_uint_at_no_overflow(layout, receiver_count_cell_index(row));
1270         return;
1271       }
1272     }
1273     // New receiver, find a free slot.
1274     for (int row = 0; row < num_rows; row++) {
1275       if (receiver_unchecked(layout, row) == NULL) {
1276         set_intptr_at(layout, receiver_cell_index(row), (intptr_t)rcvr);
1277         increment_uint_at_no_overflow(layout, receiver_count_cell_index(row));
1278         return;
1279       }
1280     }
1281     // Receiver did not match any saved receiver and there is no empty row for it.
1282     // Increment total counter to indicate polymorphic case.
1283     increment_count_no_overflow(layout);
1284   }
1285 
1286   static DataLayout* advance(DataLayout* layout) {
1287     return (DataLayout*) (((address)layout) + (ssize_t)ReceiverTypeData::receiver_type_data_size_in_bytes());
1288   }
1289 #endif // CC_INTERP
1290 
1291 #ifndef PRODUCT
1292   void print_receiver_data_on(outputStream* st) const;
1293   void print_data_on(outputStream* st, const char* extra = NULL) const;
1294 #endif
1295 };
1296 
1297 // VirtualCallData
1298 //
1299 // A VirtualCallData is used to access profiling information about a
1300 // virtual call.  For now, it has nothing more than a ReceiverTypeData.
1301 class VirtualCallData : public ReceiverTypeData {
1302 public:
1303   VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
1304     assert(layout->tag() == DataLayout::virtual_call_data_tag ||
1305            layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1306   }
1307 
1308   virtual bool is_VirtualCallData() const { return true; }
1309 
1310   static int static_cell_count() {
1311     // At this point we could add more profile state, e.g., for arguments.
1312     // But for now it's the same size as the base record type.
1313     return ReceiverTypeData::static_cell_count();
1314   }
1315 
1316   virtual int cell_count() const {
1317     return static_cell_count();
1318   }
1319 
1320   // Direct accessors
1321   static ByteSize virtual_call_data_size() {
1322     return cell_offset(static_cell_count());
1323   }
1324 
1325 #ifdef CC_INTERP
1326   static int virtual_call_data_size_in_bytes() {
1327     return cell_offset_in_bytes(static_cell_count());
1328   }
1329 
1330   static DataLayout* advance(DataLayout* layout) {
1331     return (DataLayout*) (((address)layout) + (ssize_t)VirtualCallData::virtual_call_data_size_in_bytes());
1332   }
1333 #endif // CC_INTERP
1334 
1335 #ifndef PRODUCT
1336   void print_data_on(outputStream* st, const char* extra = NULL) const;
1337 #endif
1338 };
1339 
1340 // VirtualCallTypeData
1341 //
1342 // A VirtualCallTypeData is used to access profiling information about
1343 // a virtual call for which we collect type information about
1344 // arguments and return value.
1345 class VirtualCallTypeData : public VirtualCallData {
1346 private:
1347   // entries for arguments if any
1348   TypeStackSlotEntries _args;
1349   // entry for return type if any
1350   ReturnTypeEntry _ret;
1351 
1352   int cell_count_global_offset() const {
1353     return VirtualCallData::static_cell_count() + TypeEntriesAtCall::cell_count_local_offset();
1354   }
1355 
1356   // number of cells not counting the header
1357   int cell_count_no_header() const {
1358     return uint_at(cell_count_global_offset());
1359   }
1360 
1361   void check_number_of_arguments(int total) {
1362     assert(number_of_arguments() == total, "should be set in DataLayout::initialize");
1363   }
1364 
1365 public:
1366   VirtualCallTypeData(DataLayout* layout) :
1367     VirtualCallData(layout),
1368     _args(VirtualCallData::static_cell_count()+TypeEntriesAtCall::header_cell_count(), number_of_arguments()),
1369     _ret(cell_count() - ReturnTypeEntry::static_cell_count())
1370   {
1371     assert(layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1372     // Some compilers (VC++) don't want this passed in member initialization list
1373     _args.set_profile_data(this);
1374     _ret.set_profile_data(this);
1375   }
1376 
1377   const TypeStackSlotEntries* args() const {
1378     assert(has_arguments(), "no profiling of arguments");
1379     return &_args;
1380   }
1381 
1382   const ReturnTypeEntry* ret() const {
1383     assert(has_return(), "no profiling of return value");
1384     return &_ret;
1385   }
1386 
1387   virtual bool is_VirtualCallTypeData() const { return true; }
1388 
1389   static int static_cell_count() {
1390     return -1;
1391   }
1392 
1393   static int compute_cell_count(BytecodeStream* stream) {
1394     return VirtualCallData::static_cell_count() + TypeEntriesAtCall::compute_cell_count(stream);
1395   }
1396 
1397   static void initialize(DataLayout* dl, int cell_count) {
1398     TypeEntriesAtCall::initialize(dl, VirtualCallData::static_cell_count(), cell_count);
1399   }
1400 
1401   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1402 
1403   virtual int cell_count() const {
1404     return VirtualCallData::static_cell_count() +
1405       TypeEntriesAtCall::header_cell_count() +
1406       int_at_unchecked(cell_count_global_offset());
1407   }
1408 
1409   int number_of_arguments() const {
1410     return cell_count_no_header() / TypeStackSlotEntries::per_arg_count();
1411   }
1412 
1413   void set_argument_type(int i, Klass* k) {
1414     assert(has_arguments(), "no arguments!");
1415     intptr_t current = _args.type(i);
1416     _args.set_type(i, TypeEntries::with_status(k, current));
1417   }
1418 
1419   void set_return_type(Klass* k) {
1420     assert(has_return(), "no return!");
1421     intptr_t current = _ret.type();
1422     _ret.set_type(TypeEntries::with_status(k, current));
1423   }
1424 
1425   // An entry for a return value takes less space than an entry for an
1426   // argument, so if the remainder of the number of cells divided by
1427   // the number of cells for an argument is not null, a return value
1428   // is profiled in this object.
1429   bool has_return() const {
1430     bool res = (cell_count_no_header() % TypeStackSlotEntries::per_arg_count()) != 0;
1431     assert (!res || TypeEntriesAtCall::return_profiling_enabled(), "no profiling of return values");
1432     return res;
1433   }
1434 
1435   // An entry for a return value takes less space than an entry for an
1436   // argument so if the number of cells exceeds the number of cells
1437   // needed for an argument, this object contains type information for
1438   // at least one argument.
1439   bool has_arguments() const {
1440     bool res = cell_count_no_header() >= TypeStackSlotEntries::per_arg_count();
1441     assert (!res || TypeEntriesAtCall::arguments_profiling_enabled(), "no profiling of arguments");
1442     return res;
1443   }
1444 
1445   // Code generation support
1446   static ByteSize args_data_offset() {
1447     return cell_offset(VirtualCallData::static_cell_count()) + TypeEntriesAtCall::args_data_offset();
1448   }
1449 
1450   // GC support
1451   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {
1452     ReceiverTypeData::clean_weak_klass_links(is_alive_closure);
1453     if (has_arguments()) {
1454       _args.clean_weak_klass_links(is_alive_closure);
1455     }
1456     if (has_return()) {
1457       _ret.clean_weak_klass_links(is_alive_closure);
1458     }
1459   }
1460 
1461 #ifndef PRODUCT
1462   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1463 #endif
1464 };
1465 
1466 // RetData
1467 //
1468 // A RetData is used to access profiling information for a ret bytecode.
1469 // It is composed of a count of the number of times that the ret has
1470 // been executed, followed by a series of triples of the form
1471 // (bci, count, di) which count the number of times that some bci was the
1472 // target of the ret and cache a corresponding data displacement.
1473 class RetData : public CounterData {
1474 protected:
1475   enum {
1476     bci0_offset = counter_cell_count,
1477     count0_offset,
1478     displacement0_offset,
1479     ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
1480   };
1481 
1482   void set_bci(uint row, int bci) {
1483     assert((uint)row < row_limit(), "oob");
1484     set_int_at(bci0_offset + row * ret_row_cell_count, bci);
1485   }
1486   void release_set_bci(uint row, int bci) {
1487     assert((uint)row < row_limit(), "oob");
1488     // 'release' when setting the bci acts as a valid flag for other
1489     // threads wrt bci_count and bci_displacement.
1490     release_set_int_at(bci0_offset + row * ret_row_cell_count, bci);
1491   }
1492   void set_bci_count(uint row, uint count) {
1493     assert((uint)row < row_limit(), "oob");
1494     set_uint_at(count0_offset + row * ret_row_cell_count, count);
1495   }
1496   void set_bci_displacement(uint row, int disp) {
1497     set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
1498   }
1499 
1500 public:
1501   RetData(DataLayout* layout) : CounterData(layout) {
1502     assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
1503   }
1504 
1505   virtual bool is_RetData() const { return true; }
1506 
1507   enum {
1508     no_bci = -1 // value of bci when bci1/2 are not in use.
1509   };
1510 
1511   static int static_cell_count() {
1512     return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
1513   }
1514 
1515   virtual int cell_count() const {
1516     return static_cell_count();
1517   }
1518 
1519   static uint row_limit() {
1520     return BciProfileWidth;
1521   }
1522   static int bci_cell_index(uint row) {
1523     return bci0_offset + row * ret_row_cell_count;
1524   }
1525   static int bci_count_cell_index(uint row) {
1526     return count0_offset + row * ret_row_cell_count;
1527   }
1528   static int bci_displacement_cell_index(uint row) {
1529     return displacement0_offset + row * ret_row_cell_count;
1530   }
1531 
1532   // Direct accessors
1533   int bci(uint row) const {
1534     return int_at(bci_cell_index(row));
1535   }
1536   uint bci_count(uint row) const {
1537     return uint_at(bci_count_cell_index(row));
1538   }
1539   int bci_displacement(uint row) const {
1540     return int_at(bci_displacement_cell_index(row));
1541   }
1542 
1543   // Interpreter Runtime support
1544   address fixup_ret(int return_bci, MethodData* mdo);
1545 
1546   // Code generation support
1547   static ByteSize bci_offset(uint row) {
1548     return cell_offset(bci_cell_index(row));
1549   }
1550   static ByteSize bci_count_offset(uint row) {
1551     return cell_offset(bci_count_cell_index(row));
1552   }
1553   static ByteSize bci_displacement_offset(uint row) {
1554     return cell_offset(bci_displacement_cell_index(row));
1555   }
1556 
1557 #ifdef CC_INTERP
1558   static DataLayout* advance(MethodData *md, int bci);
1559 #endif // CC_INTERP
1560 
1561   // Specific initialization.
1562   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1563 
1564 #ifndef PRODUCT
1565   void print_data_on(outputStream* st, const char* extra = NULL) const;
1566 #endif
1567 };
1568 
1569 // BranchData
1570 //
1571 // A BranchData is used to access profiling data for a two-way branch.
1572 // It consists of taken and not_taken counts as well as a data displacement
1573 // for the taken case.
1574 class BranchData : public JumpData {
1575 protected:
1576   enum {
1577     not_taken_off_set = jump_cell_count,
1578     branch_cell_count
1579   };
1580 
1581   void set_displacement(int displacement) {
1582     set_int_at(displacement_off_set, displacement);
1583   }
1584 
1585 public:
1586   BranchData(DataLayout* layout) : JumpData(layout) {
1587     assert(layout->tag() == DataLayout::branch_data_tag, "wrong type");
1588   }
1589 
1590   virtual bool is_BranchData() const { return true; }
1591 
1592   static int static_cell_count() {
1593     return branch_cell_count;
1594   }
1595 
1596   virtual int cell_count() const {
1597     return static_cell_count();
1598   }
1599 
1600   // Direct accessor
1601   uint not_taken() const {
1602     return uint_at(not_taken_off_set);
1603   }
1604 
1605   void set_not_taken(uint cnt) {
1606     set_uint_at(not_taken_off_set, cnt);
1607   }
1608 
1609   uint inc_not_taken() {
1610     uint cnt = not_taken() + 1;
1611     // Did we wrap? Will compiler screw us??
1612     if (cnt == 0) cnt--;
1613     set_uint_at(not_taken_off_set, cnt);
1614     return cnt;
1615   }
1616 
1617   // Code generation support
1618   static ByteSize not_taken_offset() {
1619     return cell_offset(not_taken_off_set);
1620   }
1621   static ByteSize branch_data_size() {
1622     return cell_offset(branch_cell_count);
1623   }
1624 
1625 #ifdef CC_INTERP
1626   static int branch_data_size_in_bytes() {
1627     return cell_offset_in_bytes(branch_cell_count);
1628   }
1629 
1630   static void increment_not_taken_count_no_overflow(DataLayout* layout) {
1631     increment_uint_at_no_overflow(layout, not_taken_off_set);
1632   }
1633 
1634   static DataLayout* advance_not_taken(DataLayout* layout) {
1635     return (DataLayout*) (((address)layout) + (ssize_t)BranchData::branch_data_size_in_bytes());
1636   }
1637 #endif // CC_INTERP
1638 
1639   // Specific initialization.
1640   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1641 
1642 #ifndef PRODUCT
1643   void print_data_on(outputStream* st, const char* extra = NULL) const;
1644 #endif
1645 };
1646 
1647 // ArrayData
1648 //
1649 // A ArrayData is a base class for accessing profiling data which does
1650 // not have a statically known size.  It consists of an array length
1651 // and an array start.
1652 class ArrayData : public ProfileData {
1653 protected:
1654   friend class DataLayout;
1655 
1656   enum {
1657     array_len_off_set,
1658     array_start_off_set
1659   };
1660 
1661   uint array_uint_at(int index) const {
1662     int aindex = index + array_start_off_set;
1663     return uint_at(aindex);
1664   }
1665   int array_int_at(int index) const {
1666     int aindex = index + array_start_off_set;
1667     return int_at(aindex);
1668   }
1669   oop array_oop_at(int index) const {
1670     int aindex = index + array_start_off_set;
1671     return oop_at(aindex);
1672   }
1673   void array_set_int_at(int index, int value) {
1674     int aindex = index + array_start_off_set;
1675     set_int_at(aindex, value);
1676   }
1677 
1678 #ifdef CC_INTERP
1679   // Static low level accessors for DataLayout with ArrayData's semantics.
1680 
1681   static void increment_array_uint_at_no_overflow(DataLayout* layout, int index) {
1682     int aindex = index + array_start_off_set;
1683     increment_uint_at_no_overflow(layout, aindex);
1684   }
1685 
1686   static int array_int_at(DataLayout* layout, int index) {
1687     int aindex = index + array_start_off_set;
1688     return int_at(layout, aindex);
1689   }
1690 #endif // CC_INTERP
1691 
1692   // Code generation support for subclasses.
1693   static ByteSize array_element_offset(int index) {
1694     return cell_offset(array_start_off_set + index);
1695   }
1696 
1697 public:
1698   ArrayData(DataLayout* layout) : ProfileData(layout) {}
1699 
1700   virtual bool is_ArrayData() const { return true; }
1701 
1702   static int static_cell_count() {
1703     return -1;
1704   }
1705 
1706   int array_len() const {
1707     return int_at_unchecked(array_len_off_set);
1708   }
1709 
1710   virtual int cell_count() const {
1711     return array_len() + 1;
1712   }
1713 
1714   // Code generation support
1715   static ByteSize array_len_offset() {
1716     return cell_offset(array_len_off_set);
1717   }
1718   static ByteSize array_start_offset() {
1719     return cell_offset(array_start_off_set);
1720   }
1721 };
1722 
1723 // MultiBranchData
1724 //
1725 // A MultiBranchData is used to access profiling information for
1726 // a multi-way branch (*switch bytecodes).  It consists of a series
1727 // of (count, displacement) pairs, which count the number of times each
1728 // case was taken and specify the data displacment for each branch target.
1729 class MultiBranchData : public ArrayData {
1730 protected:
1731   enum {
1732     default_count_off_set,
1733     default_disaplacement_off_set,
1734     case_array_start
1735   };
1736   enum {
1737     relative_count_off_set,
1738     relative_displacement_off_set,
1739     per_case_cell_count
1740   };
1741 
1742   void set_default_displacement(int displacement) {
1743     array_set_int_at(default_disaplacement_off_set, displacement);
1744   }
1745   void set_displacement_at(int index, int displacement) {
1746     array_set_int_at(case_array_start +
1747                      index * per_case_cell_count +
1748                      relative_displacement_off_set,
1749                      displacement);
1750   }
1751 
1752 public:
1753   MultiBranchData(DataLayout* layout) : ArrayData(layout) {
1754     assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
1755   }
1756 
1757   virtual bool is_MultiBranchData() const { return true; }
1758 
1759   static int compute_cell_count(BytecodeStream* stream);
1760 
1761   int number_of_cases() const {
1762     int alen = array_len() - 2; // get rid of default case here.
1763     assert(alen % per_case_cell_count == 0, "must be even");
1764     return (alen / per_case_cell_count);
1765   }
1766 
1767   uint default_count() const {
1768     return array_uint_at(default_count_off_set);
1769   }
1770   int default_displacement() const {
1771     return array_int_at(default_disaplacement_off_set);
1772   }
1773 
1774   uint count_at(int index) const {
1775     return array_uint_at(case_array_start +
1776                          index * per_case_cell_count +
1777                          relative_count_off_set);
1778   }
1779   int displacement_at(int index) const {
1780     return array_int_at(case_array_start +
1781                         index * per_case_cell_count +
1782                         relative_displacement_off_set);
1783   }
1784 
1785   // Code generation support
1786   static ByteSize default_count_offset() {
1787     return array_element_offset(default_count_off_set);
1788   }
1789   static ByteSize default_displacement_offset() {
1790     return array_element_offset(default_disaplacement_off_set);
1791   }
1792   static ByteSize case_count_offset(int index) {
1793     return case_array_offset() +
1794            (per_case_size() * index) +
1795            relative_count_offset();
1796   }
1797   static ByteSize case_array_offset() {
1798     return array_element_offset(case_array_start);
1799   }
1800   static ByteSize per_case_size() {
1801     return in_ByteSize(per_case_cell_count) * cell_size;
1802   }
1803   static ByteSize relative_count_offset() {
1804     return in_ByteSize(relative_count_off_set) * cell_size;
1805   }
1806   static ByteSize relative_displacement_offset() {
1807     return in_ByteSize(relative_displacement_off_set) * cell_size;
1808   }
1809 
1810 #ifdef CC_INTERP
1811   static void increment_count_no_overflow(DataLayout* layout, int index) {
1812     if (index == -1) {
1813       increment_array_uint_at_no_overflow(layout, default_count_off_set);
1814     } else {
1815       increment_array_uint_at_no_overflow(layout, case_array_start +
1816                                                   index * per_case_cell_count +
1817                                                   relative_count_off_set);
1818     }
1819   }
1820 
1821   static DataLayout* advance(DataLayout* layout, int index) {
1822     if (index == -1) {
1823       return (DataLayout*) (((address)layout) + (ssize_t)array_int_at(layout, default_disaplacement_off_set));
1824     } else {
1825       return (DataLayout*) (((address)layout) + (ssize_t)array_int_at(layout, case_array_start +
1826                                                                               index * per_case_cell_count +
1827                                                                               relative_displacement_off_set));
1828     }
1829   }
1830 #endif // CC_INTERP
1831 
1832   // Specific initialization.
1833   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1834 
1835 #ifndef PRODUCT
1836   void print_data_on(outputStream* st, const char* extra = NULL) const;
1837 #endif
1838 };
1839 
1840 class ArgInfoData : public ArrayData {
1841 
1842 public:
1843   ArgInfoData(DataLayout* layout) : ArrayData(layout) {
1844     assert(layout->tag() == DataLayout::arg_info_data_tag, "wrong type");
1845   }
1846 
1847   virtual bool is_ArgInfoData() const { return true; }
1848 
1849 
1850   int number_of_args() const {
1851     return array_len();
1852   }
1853 
1854   uint arg_modified(int arg) const {
1855     return array_uint_at(arg);
1856   }
1857 
1858   void set_arg_modified(int arg, uint val) {
1859     array_set_int_at(arg, val);
1860   }
1861 
1862 #ifndef PRODUCT
1863   void print_data_on(outputStream* st, const char* extra = NULL) const;
1864 #endif
1865 };
1866 
1867 // ParametersTypeData
1868 //
1869 // A ParametersTypeData is used to access profiling information about
1870 // types of parameters to a method
1871 class ParametersTypeData : public ArrayData {
1872 
1873 private:
1874   TypeStackSlotEntries _parameters;
1875 
1876   static int stack_slot_local_offset(int i) {
1877     assert_profiling_enabled();
1878     return array_start_off_set + TypeStackSlotEntries::stack_slot_local_offset(i);
1879   }
1880 
1881   static int type_local_offset(int i) {
1882     assert_profiling_enabled();
1883     return array_start_off_set + TypeStackSlotEntries::type_local_offset(i);
1884   }
1885 
1886   static bool profiling_enabled();
1887   static void assert_profiling_enabled() {
1888     assert(profiling_enabled(), "method parameters profiling should be on");
1889   }
1890 
1891 public:
1892   ParametersTypeData(DataLayout* layout) : ArrayData(layout), _parameters(1, number_of_parameters()) {
1893     assert(layout->tag() == DataLayout::parameters_type_data_tag, "wrong type");
1894     // Some compilers (VC++) don't want this passed in member initialization list
1895     _parameters.set_profile_data(this);
1896   }
1897 
1898   static int compute_cell_count(Method* m);
1899 
1900   virtual bool is_ParametersTypeData() const { return true; }
1901 
1902   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1903 
1904   int number_of_parameters() const {
1905     return array_len() / TypeStackSlotEntries::per_arg_count();
1906   }
1907 
1908   const TypeStackSlotEntries* parameters() const { return &_parameters; }
1909 
1910   uint stack_slot(int i) const {
1911     return _parameters.stack_slot(i);
1912   }
1913 
1914   void set_type(int i, Klass* k) {
1915     intptr_t current = _parameters.type(i);
1916     _parameters.set_type(i, TypeEntries::with_status((intptr_t)k, current));
1917   }
1918 
1919   virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {
1920     _parameters.clean_weak_klass_links(is_alive_closure);
1921   }
1922 
1923 #ifndef PRODUCT
1924   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1925 #endif
1926 
1927   static ByteSize stack_slot_offset(int i) {
1928     return cell_offset(stack_slot_local_offset(i));
1929   }
1930 
1931   static ByteSize type_offset(int i) {
1932     return cell_offset(type_local_offset(i));
1933   }
1934 };
1935 
1936 // SpeculativeTrapData
1937 //
1938 // A SpeculativeTrapData is used to record traps due to type
1939 // speculation. It records the root of the compilation: that type
1940 // speculation is wrong in the context of one compilation (for
1941 // method1) doesn't mean it's wrong in the context of another one (for
1942 // method2). Type speculation could have more/different data in the
1943 // context of the compilation of method2 and it's worthwhile to try an
1944 // optimization that failed for compilation of method1 in the context
1945 // of compilation of method2.
1946 // Space for SpeculativeTrapData entries is allocated from the extra
1947 // data space in the MDO. If we run out of space, the trap data for
1948 // the ProfileData at that bci is updated.
1949 class SpeculativeTrapData : public ProfileData {
1950 protected:
1951   enum {
1952     method_offset,
1953     speculative_trap_cell_count
1954   };
1955 public:
1956   SpeculativeTrapData(DataLayout* layout) : ProfileData(layout) {
1957     assert(layout->tag() == DataLayout::speculative_trap_data_tag, "wrong type");
1958   }
1959 
1960   virtual bool is_SpeculativeTrapData() const { return true; }
1961 
1962   static int static_cell_count() {
1963     return speculative_trap_cell_count;
1964   }
1965 
1966   virtual int cell_count() const {
1967     return static_cell_count();
1968   }
1969 
1970   // Direct accessor
1971   Method* method() const {
1972     return (Method*)intptr_at(method_offset);
1973   }
1974 
1975   void set_method(Method* m) {
1976     set_intptr_at(method_offset, (intptr_t)m);
1977   }
1978 
1979 #ifndef PRODUCT
1980   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1981 #endif
1982 };
1983 
1984 // MethodData*
1985 //
1986 // A MethodData* holds information which has been collected about
1987 // a method.  Its layout looks like this:
1988 //
1989 // -----------------------------
1990 // | header                    |
1991 // | klass                     |
1992 // -----------------------------
1993 // | method                    |
1994 // | size of the MethodData* |
1995 // -----------------------------
1996 // | Data entries...           |
1997 // |   (variable size)         |
1998 // |                           |
1999 // .                           .
2000 // .                           .
2001 // .                           .
2002 // |                           |
2003 // -----------------------------
2004 //
2005 // The data entry area is a heterogeneous array of DataLayouts. Each
2006 // DataLayout in the array corresponds to a specific bytecode in the
2007 // method.  The entries in the array are sorted by the corresponding
2008 // bytecode.  Access to the data is via resource-allocated ProfileData,
2009 // which point to the underlying blocks of DataLayout structures.
2010 //
2011 // During interpretation, if profiling in enabled, the interpreter
2012 // maintains a method data pointer (mdp), which points at the entry
2013 // in the array corresponding to the current bci.  In the course of
2014 // intepretation, when a bytecode is encountered that has profile data
2015 // associated with it, the entry pointed to by mdp is updated, then the
2016 // mdp is adjusted to point to the next appropriate DataLayout.  If mdp
2017 // is NULL to begin with, the interpreter assumes that the current method
2018 // is not (yet) being profiled.
2019 //
2020 // In MethodData* parlance, "dp" is a "data pointer", the actual address
2021 // of a DataLayout element.  A "di" is a "data index", the offset in bytes
2022 // from the base of the data entry array.  A "displacement" is the byte offset
2023 // in certain ProfileData objects that indicate the amount the mdp must be
2024 // adjusted in the event of a change in control flow.
2025 //
2026 
2027 CC_INTERP_ONLY(class BytecodeInterpreter;)
2028 
2029 class MethodData : public Metadata {
2030   friend class VMStructs;
2031   CC_INTERP_ONLY(friend class BytecodeInterpreter;)
2032 private:
2033   friend class ProfileData;
2034 
2035   // Back pointer to the Method*
2036   Method* _method;
2037 
2038   // Size of this oop in bytes
2039   int _size;
2040 
2041   // Cached hint for bci_to_dp and bci_to_data
2042   int _hint_di;
2043 
2044   Mutex _extra_data_lock;
2045 
2046   MethodData(methodHandle method, int size, TRAPS);
2047 public:
2048   static MethodData* allocate(ClassLoaderData* loader_data, methodHandle method, TRAPS);
2049   MethodData() : _extra_data_lock(Monitor::leaf, "MDO extra data lock") {}; // For ciMethodData
2050 
2051   bool is_methodData() const volatile { return true; }
2052 
2053   // Whole-method sticky bits and flags
2054   enum {
2055     _trap_hist_limit    = 18,   // decoupled from Deoptimization::Reason_LIMIT
2056     _trap_hist_mask     = max_jubyte,
2057     _extra_data_count   = 4     // extra DataLayout headers, for trap history
2058   }; // Public flag values
2059 private:
2060   uint _nof_decompiles;             // count of all nmethod removals
2061   uint _nof_overflow_recompiles;    // recompile count, excluding recomp. bits
2062   uint _nof_overflow_traps;         // trap count, excluding _trap_hist
2063   union {
2064     intptr_t _align;
2065     u1 _array[_trap_hist_limit];
2066   } _trap_hist;
2067 
2068   // Support for interprocedural escape analysis, from Thomas Kotzmann.
2069   intx              _eflags;          // flags on escape information
2070   intx              _arg_local;       // bit set of non-escaping arguments
2071   intx              _arg_stack;       // bit set of stack-allocatable arguments
2072   intx              _arg_returned;    // bit set of returned arguments
2073 
2074   int _creation_mileage;              // method mileage at MDO creation
2075 
2076   // How many invocations has this MDO seen?
2077   // These counters are used to determine the exact age of MDO.
2078   // We need those because in tiered a method can be concurrently
2079   // executed at different levels.
2080   InvocationCounter _invocation_counter;
2081   // Same for backedges.
2082   InvocationCounter _backedge_counter;
2083   // Counter values at the time profiling started.
2084   int               _invocation_counter_start;
2085   int               _backedge_counter_start;
2086   // Number of loops and blocks is computed when compiling the first
2087   // time with C1. It is used to determine if method is trivial.
2088   short             _num_loops;
2089   short             _num_blocks;
2090   // Highest compile level this method has ever seen.
2091   u1                _highest_comp_level;
2092   // Same for OSR level
2093   u1                _highest_osr_comp_level;
2094   // Does this method contain anything worth profiling?
2095   bool              _would_profile;
2096 
2097   // Size of _data array in bytes.  (Excludes header and extra_data fields.)
2098   int _data_size;
2099 
2100   // data index for the area dedicated to parameters. -1 if no
2101   // parameter profiling.
2102   int _parameters_type_data_di;
2103 
2104   // Beginning of the data entries
2105   intptr_t _data[1];
2106 
2107   // Helper for size computation
2108   static int compute_data_size(BytecodeStream* stream);
2109   static int bytecode_cell_count(Bytecodes::Code code);
2110   static bool is_speculative_trap_bytecode(Bytecodes::Code code);
2111   enum { no_profile_data = -1, variable_cell_count = -2 };
2112 
2113   // Helper for initialization
2114   DataLayout* data_layout_at(int data_index) const {
2115     assert(data_index % sizeof(intptr_t) == 0, "unaligned");
2116     return (DataLayout*) (((address)_data) + data_index);
2117   }
2118 
2119   // Initialize an individual data segment.  Returns the size of
2120   // the segment in bytes.
2121   int initialize_data(BytecodeStream* stream, int data_index);
2122 
2123   // Helper for data_at
2124   DataLayout* limit_data_position() const {
2125     return (DataLayout*)((address)data_base() + _data_size);
2126   }
2127   bool out_of_bounds(int data_index) const {
2128     return data_index >= data_size();
2129   }
2130 
2131   // Give each of the data entries a chance to perform specific
2132   // data initialization.
2133   void post_initialize(BytecodeStream* stream);
2134 
2135   // hint accessors
2136   int      hint_di() const  { return _hint_di; }
2137   void set_hint_di(int di)  {
2138     assert(!out_of_bounds(di), "hint_di out of bounds");
2139     _hint_di = di;
2140   }
2141   ProfileData* data_before(int bci) {
2142     // avoid SEGV on this edge case
2143     if (data_size() == 0)
2144       return NULL;
2145     int hint = hint_di();
2146     if (data_layout_at(hint)->bci() <= bci)
2147       return data_at(hint);
2148     return first_data();
2149   }
2150 
2151   // What is the index of the first data entry?
2152   int first_di() const { return 0; }
2153 
2154   ProfileData* bci_to_extra_data_helper(int bci, Method* m, DataLayout*& dp, bool concurrent);
2155   // Find or create an extra ProfileData:
2156   ProfileData* bci_to_extra_data(int bci, Method* m, bool create_if_missing);
2157 
2158   // return the argument info cell
2159   ArgInfoData *arg_info();
2160 
2161   enum {
2162     no_type_profile = 0,
2163     type_profile_jsr292 = 1,
2164     type_profile_all = 2
2165   };
2166 
2167   static bool profile_jsr292(methodHandle m, int bci);
2168   static int profile_arguments_flag();
2169   static bool profile_arguments_jsr292_only();
2170   static bool profile_all_arguments();
2171   static bool profile_arguments_for_invoke(methodHandle m, int bci);
2172   static int profile_return_flag();
2173   static bool profile_all_return();
2174   static bool profile_return_for_invoke(methodHandle m, int bci);
2175   static int profile_parameters_flag();
2176   static bool profile_parameters_jsr292_only();
2177   static bool profile_all_parameters();
2178 
2179   void clean_extra_data(BoolObjectClosure* is_alive);
2180   void clean_extra_data_helper(DataLayout* dp, int shift, bool reset = false);
2181   void verify_extra_data_clean(BoolObjectClosure* is_alive);
2182 
2183 public:
2184   static int header_size() {
2185     return sizeof(MethodData)/wordSize;
2186   }
2187 
2188   // Compute the size of a MethodData* before it is created.
2189   static int compute_allocation_size_in_bytes(methodHandle method);
2190   static int compute_allocation_size_in_words(methodHandle method);
2191   static int compute_extra_data_count(int data_size, int empty_bc_count, bool needs_speculative_traps);
2192 
2193   // Determine if a given bytecode can have profile information.
2194   static bool bytecode_has_profile(Bytecodes::Code code) {
2195     return bytecode_cell_count(code) != no_profile_data;
2196   }
2197 
2198   // reset into original state
2199   void init();
2200 
2201   // My size
2202   int size_in_bytes() const { return _size; }
2203   int size() const    { return align_object_size(align_size_up(_size, BytesPerWord)/BytesPerWord); }
2204 #if INCLUDE_SERVICES
2205   void collect_statistics(KlassSizeStats *sz) const;
2206 #endif
2207 
2208   int      creation_mileage() const  { return _creation_mileage; }
2209   void set_creation_mileage(int x)   { _creation_mileage = x; }
2210 
2211   int invocation_count() {
2212     if (invocation_counter()->carry()) {
2213       return InvocationCounter::count_limit;
2214     }
2215     return invocation_counter()->count();
2216   }
2217   int backedge_count() {
2218     if (backedge_counter()->carry()) {
2219       return InvocationCounter::count_limit;
2220     }
2221     return backedge_counter()->count();
2222   }
2223 
2224   int invocation_count_start() {
2225     if (invocation_counter()->carry()) {
2226       return 0;
2227     }
2228     return _invocation_counter_start;
2229   }
2230 
2231   int backedge_count_start() {
2232     if (backedge_counter()->carry()) {
2233       return 0;
2234     }
2235     return _backedge_counter_start;
2236   }
2237 
2238   int invocation_count_delta() { return invocation_count() - invocation_count_start(); }
2239   int backedge_count_delta()   { return backedge_count()   - backedge_count_start();   }
2240 
2241   void reset_start_counters() {
2242     _invocation_counter_start = invocation_count();
2243     _backedge_counter_start = backedge_count();
2244   }
2245 
2246   InvocationCounter* invocation_counter()     { return &_invocation_counter; }
2247   InvocationCounter* backedge_counter()       { return &_backedge_counter;   }
2248 
2249   void set_would_profile(bool p)              { _would_profile = p;    }
2250   bool would_profile() const                  { return _would_profile; }
2251 
2252   int highest_comp_level() const              { return _highest_comp_level;      }
2253   void set_highest_comp_level(int level)      { _highest_comp_level = level;     }
2254   int highest_osr_comp_level() const          { return _highest_osr_comp_level;  }
2255   void set_highest_osr_comp_level(int level)  { _highest_osr_comp_level = level; }
2256 
2257   int num_loops() const                       { return _num_loops;  }
2258   void set_num_loops(int n)                   { _num_loops = n;     }
2259   int num_blocks() const                      { return _num_blocks; }
2260   void set_num_blocks(int n)                  { _num_blocks = n;    }
2261 
2262   bool is_mature() const;  // consult mileage and ProfileMaturityPercentage
2263   static int mileage_of(Method* m);
2264 
2265   // Support for interprocedural escape analysis, from Thomas Kotzmann.
2266   enum EscapeFlag {
2267     estimated    = 1 << 0,
2268     return_local = 1 << 1,
2269     return_allocated = 1 << 2,
2270     allocated_escapes = 1 << 3,
2271     unknown_modified = 1 << 4
2272   };
2273 
2274   intx eflags()                                  { return _eflags; }
2275   intx arg_local()                               { return _arg_local; }
2276   intx arg_stack()                               { return _arg_stack; }
2277   intx arg_returned()                            { return _arg_returned; }
2278   uint arg_modified(int a)                       { ArgInfoData *aid = arg_info();
2279                                                    assert(aid != NULL, "arg_info must be not null");
2280                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
2281                                                    return aid->arg_modified(a); }
2282 
2283   void set_eflags(intx v)                        { _eflags = v; }
2284   void set_arg_local(intx v)                     { _arg_local = v; }
2285   void set_arg_stack(intx v)                     { _arg_stack = v; }
2286   void set_arg_returned(intx v)                  { _arg_returned = v; }
2287   void set_arg_modified(int a, uint v)           { ArgInfoData *aid = arg_info();
2288                                                    assert(aid != NULL, "arg_info must be not null");
2289                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
2290                                                    aid->set_arg_modified(a, v); }
2291 
2292   void clear_escape_info()                       { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
2293 
2294   // Location and size of data area
2295   address data_base() const {
2296     return (address) _data;
2297   }
2298   int data_size() const {
2299     return _data_size;
2300   }
2301 
2302   // Accessors
2303   Method* method() const { return _method; }
2304 
2305   // Get the data at an arbitrary (sort of) data index.
2306   ProfileData* data_at(int data_index) const;
2307 
2308   // Walk through the data in order.
2309   ProfileData* first_data() const { return data_at(first_di()); }
2310   ProfileData* next_data(ProfileData* current) const;
2311   bool is_valid(ProfileData* current) const { return current != NULL; }
2312 
2313   // Convert a dp (data pointer) to a di (data index).
2314   int dp_to_di(address dp) const {
2315     return dp - ((address)_data);
2316   }
2317 
2318   address di_to_dp(int di) {
2319     return (address)data_layout_at(di);
2320   }
2321 
2322   // bci to di/dp conversion.
2323   address bci_to_dp(int bci);
2324   int bci_to_di(int bci) {
2325     return dp_to_di(bci_to_dp(bci));
2326   }
2327 
2328   // Get the data at an arbitrary bci, or NULL if there is none.
2329   ProfileData* bci_to_data(int bci);
2330 
2331   // Same, but try to create an extra_data record if one is needed:
2332   ProfileData* allocate_bci_to_data(int bci, Method* m) {
2333     ProfileData* data = NULL;
2334     // If m not NULL, try to allocate a SpeculativeTrapData entry
2335     if (m == NULL) {
2336       data = bci_to_data(bci);
2337     }
2338     if (data != NULL) {
2339       return data;
2340     }
2341     data = bci_to_extra_data(bci, m, true);
2342     if (data != NULL) {
2343       return data;
2344     }
2345     // If SpeculativeTrapData allocation fails try to allocate a
2346     // regular entry
2347     data = bci_to_data(bci);
2348     if (data != NULL) {
2349       return data;
2350     }
2351     return bci_to_extra_data(bci, NULL, true);
2352   }
2353 
2354   // Add a handful of extra data records, for trap tracking.
2355   DataLayout* extra_data_base() const { return limit_data_position(); }
2356   DataLayout* extra_data_limit() const { return (DataLayout*)((address)this + size_in_bytes()); }
2357   int extra_data_size() const { return (address)extra_data_limit()
2358                                - (address)extra_data_base(); }
2359   static DataLayout* next_extra(DataLayout* dp);
2360 
2361   // Return (uint)-1 for overflow.
2362   uint trap_count(int reason) const {
2363     assert((uint)reason < _trap_hist_limit, "oob");
2364     return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
2365   }
2366   // For loops:
2367   static uint trap_reason_limit() { return _trap_hist_limit; }
2368   static uint trap_count_limit()  { return _trap_hist_mask; }
2369   uint inc_trap_count(int reason) {
2370     // Count another trap, anywhere in this method.
2371     assert(reason >= 0, "must be single trap");
2372     if ((uint)reason < _trap_hist_limit) {
2373       uint cnt1 = 1 + _trap_hist._array[reason];
2374       if ((cnt1 & _trap_hist_mask) != 0) {  // if no counter overflow...
2375         _trap_hist._array[reason] = cnt1;
2376         return cnt1;
2377       } else {
2378         return _trap_hist_mask + (++_nof_overflow_traps);
2379       }
2380     } else {
2381       // Could not represent the count in the histogram.
2382       return (++_nof_overflow_traps);
2383     }
2384   }
2385 
2386   uint overflow_trap_count() const {
2387     return _nof_overflow_traps;
2388   }
2389   uint overflow_recompile_count() const {
2390     return _nof_overflow_recompiles;
2391   }
2392   void inc_overflow_recompile_count() {
2393     _nof_overflow_recompiles += 1;
2394   }
2395   uint decompile_count() const {
2396     return _nof_decompiles;
2397   }
2398   void inc_decompile_count() {
2399     _nof_decompiles += 1;
2400     if (decompile_count() > (uint)PerMethodRecompilationCutoff) {
2401       method()->set_not_compilable(CompLevel_full_optimization, true, "decompile_count > PerMethodRecompilationCutoff");
2402     }
2403   }
2404 
2405   // Return pointer to area dedicated to parameters in MDO
2406   ParametersTypeData* parameters_type_data() const {
2407     return _parameters_type_data_di != -1 ? data_layout_at(_parameters_type_data_di)->data_in()->as_ParametersTypeData() : NULL;
2408   }
2409 
2410   int parameters_type_data_di() const {
2411     assert(_parameters_type_data_di != -1, "no args type data");
2412     return _parameters_type_data_di;
2413   }
2414 
2415   // Support for code generation
2416   static ByteSize data_offset() {
2417     return byte_offset_of(MethodData, _data[0]);
2418   }
2419 
2420   static ByteSize invocation_counter_offset() {
2421     return byte_offset_of(MethodData, _invocation_counter);
2422   }
2423   static ByteSize backedge_counter_offset() {
2424     return byte_offset_of(MethodData, _backedge_counter);
2425   }
2426 
2427   static ByteSize parameters_type_data_di_offset() {
2428     return byte_offset_of(MethodData, _parameters_type_data_di);
2429   }
2430 
2431   // Deallocation support - no pointer fields to deallocate
2432   void deallocate_contents(ClassLoaderData* loader_data) {}
2433 
2434   // GC support
2435   void set_size(int object_size_in_bytes) { _size = object_size_in_bytes; }
2436 
2437   // Printing
2438 #ifndef PRODUCT
2439   void print_on      (outputStream* st) const;
2440 #endif
2441   void print_value_on(outputStream* st) const;
2442 
2443 #ifndef PRODUCT
2444   // printing support for method data
2445   void print_data_on(outputStream* st) const;
2446 #endif
2447 
2448   const char* internal_name() const { return "{method data}"; }
2449 
2450   // verification
2451   void verify_on(outputStream* st);
2452   void verify_data_on(outputStream* st);
2453 
2454   static bool profile_parameters_for_method(methodHandle m);
2455   static bool profile_arguments();
2456   static bool profile_return();
2457   static bool profile_parameters();
2458   static bool profile_return_jsr292_only();
2459 
2460   void clean_method_data(BoolObjectClosure* is_alive);
2461 };
2462 
2463 #endif // SHARE_VM_OOPS_METHODDATAOOP_HPP