1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * under the terms of the GNU General Public License version 2 only, as
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  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).
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  24 
  25 #ifndef SHARE_OOPS_METHODDATA_HPP
  26 #define SHARE_OOPS_METHODDATA_HPP
  27 
  28 #include "interpreter/bytecodes.hpp"
  29 #include "oops/metadata.hpp"
  30 #include "oops/method.hpp"
  31 #include "oops/oop.hpp"
  32 #include "runtime/atomic.hpp"
  33 #include "runtime/deoptimization.hpp"
  34 #include "runtime/mutex.hpp"
  35 #include "utilities/align.hpp"
  36 #include "utilities/copy.hpp"
  37 
  38 class BytecodeStream;
  39 
  40 // The MethodData object collects counts and other profile information
  41 // during zeroth-tier (interpreter) and third-tier (C1 with full profiling)
  42 // execution.
  43 //
  44 // The profile is used later by compilation heuristics.  Some heuristics
  45 // enable use of aggressive (or "heroic") optimizations.  An aggressive
  46 // optimization often has a down-side, a corner case that it handles
  47 // poorly, but which is thought to be rare.  The profile provides
  48 // evidence of this rarity for a given method or even BCI.  It allows
  49 // the compiler to back out of the optimization at places where it
  50 // has historically been a poor choice.  Other heuristics try to use
  51 // specific information gathered about types observed at a given site.
  52 //
  53 // All data in the profile is approximate.  It is expected to be accurate
  54 // on the whole, but the system expects occasional inaccuraces, due to
  55 // counter overflow, multiprocessor races during data collection, space
  56 // limitations, missing MDO blocks, etc.  Bad or missing data will degrade
  57 // optimization quality but will not affect correctness.  Also, each MDO
  58 // is marked with its birth-date ("creation_mileage") which can be used
  59 // to assess the quality ("maturity") of its data.
  60 //
  61 // Short (<32-bit) counters are designed to overflow to a known "saturated"
  62 // state.  Also, certain recorded per-BCI events are given one-bit counters
  63 // which overflow to a saturated state which applied to all counters at
  64 // that BCI.  In other words, there is a small lattice which approximates
  65 // the ideal of an infinite-precision counter for each event at each BCI,
  66 // and the lattice quickly "bottoms out" in a state where all counters
  67 // are taken to be indefinitely large.
  68 //
  69 // The reader will find many data races in profile gathering code, starting
  70 // with invocation counter incrementation.  None of these races harm correct
  71 // execution of the compiled code.
  72 
  73 // forward decl
  74 class ProfileData;
  75 
  76 // DataLayout
  77 //
  78 // Overlay for generic profiling data.
  79 class DataLayout {
  80   friend class VMStructs;
  81   friend class JVMCIVMStructs;
  82 
  83 private:
  84   // Every data layout begins with a header.  This header
  85   // contains a tag, which is used to indicate the size/layout
  86   // of the data, 8 bits of flags, which can be used in any way,
  87   // 32 bits of trap history (none/one reason/many reasons),
  88   // and a bci, which is used to tie this piece of data to a
  89   // specific bci in the bytecodes.
  90   union {
  91     u8 _bits;
  92     struct {
  93       u1 _tag;
  94       u1 _flags;
  95       u2 _bci;
  96       u4 _traps;
  97     } _struct;
  98   } _header;
  99 
 100   // The data layout has an arbitrary number of cells, each sized
 101   // to accommodate a pointer or an integer.
 102   intptr_t _cells[1];
 103 
 104   // Some types of data layouts need a length field.
 105   static bool needs_array_len(u1 tag);
 106 
 107 public:
 108   enum {
 109     counter_increment = 1
 110   };
 111 
 112   enum {
 113     cell_size = sizeof(intptr_t)
 114   };
 115 
 116   // Tag values
 117   enum {
 118     no_tag,
 119     bit_data_tag,
 120     counter_data_tag,
 121     jump_data_tag,
 122     receiver_type_data_tag,
 123     virtual_call_data_tag,
 124     ret_data_tag,
 125     branch_data_tag,
 126     multi_branch_data_tag,
 127     arg_info_data_tag,
 128     call_type_data_tag,
 129     virtual_call_type_data_tag,
 130     parameters_type_data_tag,
 131     speculative_trap_data_tag,
 132     array_load_store_data_tag,
 133     acmp_data_tag
 134   };
 135 
 136   enum {
 137     // The trap state breaks down as [recompile:1 | reason:31].
 138     // This further breakdown is defined in deoptimization.cpp.
 139     // See Deoptimization::trap_state_reason for an assert that
 140     // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
 141     //
 142     // The trap_state is collected only if ProfileTraps is true.
 143     trap_bits = 1+31,  // 31: enough to distinguish [0..Reason_RECORDED_LIMIT].
 144     trap_mask = -1,
 145     first_flag = 0
 146   };
 147 
 148   // Size computation
 149   static int header_size_in_bytes() {
 150     return header_size_in_cells() * cell_size;
 151   }
 152   static int header_size_in_cells() {
 153     return LP64_ONLY(1) NOT_LP64(2);
 154   }
 155 
 156   static int compute_size_in_bytes(int cell_count) {
 157     return header_size_in_bytes() + cell_count * cell_size;
 158   }
 159 
 160   // Initialization
 161   void initialize(u1 tag, u2 bci, int cell_count);
 162 
 163   // Accessors
 164   u1 tag() {
 165     return _header._struct._tag;
 166   }
 167 
 168   // Return 32 bits of trap state.
 169   // The state tells if traps with zero, one, or many reasons have occurred.
 170   // It also tells whether zero or many recompilations have occurred.
 171   // The associated trap histogram in the MDO itself tells whether
 172   // traps are common or not.  If a BCI shows that a trap X has
 173   // occurred, and the MDO shows N occurrences of X, we make the
 174   // simplifying assumption that all N occurrences can be blamed
 175   // on that BCI.
 176   uint trap_state() const {
 177     return _header._struct._traps;
 178   }
 179 
 180   void set_trap_state(uint new_state) {
 181     assert(ProfileTraps, "used only under +ProfileTraps");
 182     uint old_flags = _header._struct._traps;
 183     _header._struct._traps = new_state | old_flags;
 184   }
 185 
 186   u1 flags() const {
 187     return _header._struct._flags;
 188   }
 189 
 190   u2 bci() const {
 191     return _header._struct._bci;
 192   }
 193 
 194   void set_header(u8 value) {
 195     _header._bits = value;
 196   }
 197   u8 header() {
 198     return _header._bits;
 199   }
 200   void set_cell_at(int index, intptr_t value) {
 201     _cells[index] = value;
 202   }
 203   void release_set_cell_at(int index, intptr_t value);
 204   intptr_t cell_at(int index) const {
 205     return _cells[index];
 206   }
 207 
 208   void set_flag_at(u1 flag_number) {
 209     _header._struct._flags |= (0x1 << flag_number);
 210   }
 211   bool flag_at(u1 flag_number) const {
 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   // Return a value which, when or-ed as a byte into _flags, sets the flag.
 232   static u1 flag_number_to_constant(u1 flag_number) {
 233     DataLayout temp; temp.set_header(0);
 234     temp.set_flag_at(flag_number);
 235     return temp._header._struct._flags;
 236   }
 237   // Return a value which, when or-ed as a word into _header, sets the flag.
 238   static u8 flag_mask_to_header_mask(uint byte_constant) {
 239     DataLayout temp; temp.set_header(0);
 240     temp._header._struct._flags = byte_constant;
 241     return temp._header._bits;
 242   }
 243 
 244   ProfileData* data_in();
 245 
 246   int size_in_bytes() {
 247     int cells = cell_count();
 248     assert(cells >= 0, "invalid number of cells");
 249     return DataLayout::compute_size_in_bytes(cells);
 250   }
 251   int cell_count();
 252 
 253   // GC support
 254   void clean_weak_klass_links(bool always_clean);
 255 };
 256 
 257 
 258 // ProfileData class hierarchy
 259 class ProfileData;
 260 class   BitData;
 261 class     CounterData;
 262 class       ReceiverTypeData;
 263 class         VirtualCallData;
 264 class           VirtualCallTypeData;
 265 class       RetData;
 266 class       CallTypeData;
 267 class   JumpData;
 268 class     BranchData;
 269 class       ACmpData;
 270 class   ArrayData;
 271 class     MultiBranchData;
 272 class     ArgInfoData;
 273 class     ParametersTypeData;
 274 class   SpeculativeTrapData;
 275 class   ArrayLoadStoreData;
 276 
 277 // ProfileData
 278 //
 279 // A ProfileData object is created to refer to a section of profiling
 280 // data in a structured way.
 281 class ProfileData : public ResourceObj {
 282   friend class TypeEntries;
 283   friend class SingleTypeEntry;
 284   friend class TypeStackSlotEntries;
 285 private:
 286   enum {
 287     tab_width_one = 16,
 288     tab_width_two = 36
 289   };
 290 
 291   // This is a pointer to a section of profiling data.
 292   DataLayout* _data;
 293 
 294   char* print_data_on_helper(const MethodData* md) const;
 295 
 296 protected:
 297   DataLayout* data() { return _data; }
 298   const DataLayout* data() const { return _data; }
 299 
 300   enum {
 301     cell_size = DataLayout::cell_size
 302   };
 303 
 304 public:
 305   // How many cells are in this?
 306   virtual int cell_count() const {
 307     ShouldNotReachHere();
 308     return -1;
 309   }
 310 
 311   // Return the size of this data.
 312   int size_in_bytes() {
 313     return DataLayout::compute_size_in_bytes(cell_count());
 314   }
 315 
 316 protected:
 317   // Low-level accessors for underlying data
 318   void set_intptr_at(int index, intptr_t value) {
 319     assert(0 <= index && index < cell_count(), "oob");
 320     data()->set_cell_at(index, value);
 321   }
 322   void release_set_intptr_at(int index, intptr_t value);
 323   intptr_t intptr_at(int index) const {
 324     assert(0 <= index && index < cell_count(), "oob");
 325     return data()->cell_at(index);
 326   }
 327   void set_uint_at(int index, uint value) {
 328     set_intptr_at(index, (intptr_t) value);
 329   }
 330   void release_set_uint_at(int index, uint value);
 331   uint uint_at(int index) const {
 332     return (uint)intptr_at(index);
 333   }
 334   void set_int_at(int index, int value) {
 335     set_intptr_at(index, (intptr_t) value);
 336   }
 337   void release_set_int_at(int index, int value);
 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_constant(int flag_number) {
 363     return DataLayout::flag_number_to_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   virtual bool is_SpeculativeTrapData()const { return false; }
 404   virtual bool is_ArrayLoadStoreData() const { return false; }
 405   virtual bool is_ACmpData()           const { return false; }
 406 
 407 
 408   BitData* as_BitData() const {
 409     assert(is_BitData(), "wrong type");
 410     return is_BitData()         ? (BitData*)        this : NULL;
 411   }
 412   CounterData* as_CounterData() const {
 413     assert(is_CounterData(), "wrong type");
 414     return is_CounterData()     ? (CounterData*)    this : NULL;
 415   }
 416   JumpData* as_JumpData() const {
 417     assert(is_JumpData(), "wrong type");
 418     return is_JumpData()        ? (JumpData*)       this : NULL;
 419   }
 420   ReceiverTypeData* as_ReceiverTypeData() const {
 421     assert(is_ReceiverTypeData(), "wrong type");
 422     return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
 423   }
 424   VirtualCallData* as_VirtualCallData() const {
 425     assert(is_VirtualCallData(), "wrong type");
 426     return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
 427   }
 428   RetData* as_RetData() const {
 429     assert(is_RetData(), "wrong type");
 430     return is_RetData()         ? (RetData*)        this : NULL;
 431   }
 432   BranchData* as_BranchData() const {
 433     assert(is_BranchData(), "wrong type");
 434     return is_BranchData()      ? (BranchData*)     this : NULL;
 435   }
 436   ArrayData* as_ArrayData() const {
 437     assert(is_ArrayData(), "wrong type");
 438     return is_ArrayData()       ? (ArrayData*)      this : NULL;
 439   }
 440   MultiBranchData* as_MultiBranchData() const {
 441     assert(is_MultiBranchData(), "wrong type");
 442     return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
 443   }
 444   ArgInfoData* as_ArgInfoData() const {
 445     assert(is_ArgInfoData(), "wrong type");
 446     return is_ArgInfoData() ? (ArgInfoData*)this : NULL;
 447   }
 448   CallTypeData* as_CallTypeData() const {
 449     assert(is_CallTypeData(), "wrong type");
 450     return is_CallTypeData() ? (CallTypeData*)this : NULL;
 451   }
 452   VirtualCallTypeData* as_VirtualCallTypeData() const {
 453     assert(is_VirtualCallTypeData(), "wrong type");
 454     return is_VirtualCallTypeData() ? (VirtualCallTypeData*)this : NULL;
 455   }
 456   ParametersTypeData* as_ParametersTypeData() const {
 457     assert(is_ParametersTypeData(), "wrong type");
 458     return is_ParametersTypeData() ? (ParametersTypeData*)this : NULL;
 459   }
 460   SpeculativeTrapData* as_SpeculativeTrapData() const {
 461     assert(is_SpeculativeTrapData(), "wrong type");
 462     return is_SpeculativeTrapData() ? (SpeculativeTrapData*)this : NULL;
 463   }
 464   ArrayLoadStoreData* as_ArrayLoadStoreData() const {
 465     assert(is_ArrayLoadStoreData(), "wrong type");
 466     return is_ArrayLoadStoreData() ? (ArrayLoadStoreData*)this : NULL;
 467   }
 468   ACmpData* as_ACmpData() const {
 469     assert(is_ACmpData(), "wrong type");
 470     return is_ACmpData() ? (ACmpData*)this : NULL;
 471   }
 472 
 473 
 474   // Subclass specific initialization
 475   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo) {}
 476 
 477   // GC support
 478   virtual void clean_weak_klass_links(bool always_clean) {}
 479 
 480   // CI translation: ProfileData can represent both MethodDataOop data
 481   // as well as CIMethodData data. This function is provided for translating
 482   // an oop in a ProfileData to the ci equivalent. Generally speaking,
 483   // most ProfileData don't require any translation, so we provide the null
 484   // translation here, and the required translators are in the ci subclasses.
 485   virtual void translate_from(const ProfileData* data) {}
 486 
 487   virtual void print_data_on(outputStream* st, const char* extra = NULL) const {
 488     ShouldNotReachHere();
 489   }
 490 
 491   void print_data_on(outputStream* st, const MethodData* md) const;
 492 
 493   void print_shared(outputStream* st, const char* name, const char* extra) const;
 494   void tab(outputStream* st, bool first = false) const;
 495 };
 496 
 497 // BitData
 498 //
 499 // A BitData holds a flag or two in its header.
 500 class BitData : public ProfileData {
 501   friend class VMStructs;
 502   friend class JVMCIVMStructs;
 503 protected:
 504   enum {
 505     // null_seen:
 506     //  saw a null operand (cast/aastore/instanceof)
 507       null_seen_flag              = DataLayout::first_flag + 0
 508 #if INCLUDE_JVMCI
 509     // bytecode threw any exception
 510     , exception_seen_flag         = null_seen_flag + 1
 511 #endif
 512   };
 513   enum { bit_cell_count = 0 };  // no additional data fields needed.
 514 public:
 515   BitData(DataLayout* layout) : ProfileData(layout) {
 516   }
 517 
 518   virtual bool is_BitData() const { return true; }
 519 
 520   static int static_cell_count() {
 521     return bit_cell_count;
 522   }
 523 
 524   virtual int cell_count() const {
 525     return static_cell_count();
 526   }
 527 
 528   // Accessor
 529 
 530   // The null_seen flag bit is specially known to the interpreter.
 531   // Consulting it allows the compiler to avoid setting up null_check traps.
 532   bool null_seen()     { return flag_at(null_seen_flag); }
 533   void set_null_seen()    { set_flag_at(null_seen_flag); }
 534 
 535 #if INCLUDE_JVMCI
 536   // true if an exception was thrown at the specific BCI
 537   bool exception_seen() { return flag_at(exception_seen_flag); }
 538   void set_exception_seen() { set_flag_at(exception_seen_flag); }
 539 #endif
 540 
 541   // Code generation support
 542   static int null_seen_byte_constant() {
 543     return flag_number_to_constant(null_seen_flag);
 544   }
 545 
 546   static ByteSize bit_data_size() {
 547     return cell_offset(bit_cell_count);
 548   }
 549 
 550   void print_data_on(outputStream* st, const char* extra = NULL) const;
 551 };
 552 
 553 // CounterData
 554 //
 555 // A CounterData corresponds to a simple counter.
 556 class CounterData : public BitData {
 557   friend class VMStructs;
 558   friend class JVMCIVMStructs;
 559 protected:
 560   enum {
 561     count_off,
 562     counter_cell_count
 563   };
 564 public:
 565   CounterData(DataLayout* layout) : BitData(layout) {}
 566 
 567   virtual bool is_CounterData() const { return true; }
 568 
 569   static int static_cell_count() {
 570     return counter_cell_count;
 571   }
 572 
 573   virtual int cell_count() const {
 574     return static_cell_count();
 575   }
 576 
 577   // Direct accessor
 578   int count() const {
 579     intptr_t raw_data = intptr_at(count_off);
 580     if (raw_data > max_jint) {
 581       raw_data = max_jint;
 582     } else if (raw_data < min_jint) {
 583       raw_data = min_jint;
 584     }
 585     return int(raw_data);
 586   }
 587 
 588   // Code generation support
 589   static ByteSize count_offset() {
 590     return cell_offset(count_off);
 591   }
 592   static ByteSize counter_data_size() {
 593     return cell_offset(counter_cell_count);
 594   }
 595 
 596   void set_count(int count) {
 597     set_int_at(count_off, count);
 598   }
 599 
 600   void print_data_on(outputStream* st, const char* extra = NULL) const;
 601 };
 602 
 603 // JumpData
 604 //
 605 // A JumpData is used to access profiling information for a direct
 606 // branch.  It is a counter, used for counting the number of branches,
 607 // plus a data displacement, used for realigning the data pointer to
 608 // the corresponding target bci.
 609 class JumpData : public ProfileData {
 610   friend class VMStructs;
 611   friend class JVMCIVMStructs;
 612 protected:
 613   enum {
 614     taken_off_set,
 615     displacement_off_set,
 616     jump_cell_count
 617   };
 618 
 619   void set_displacement(int displacement) {
 620     set_int_at(displacement_off_set, displacement);
 621   }
 622 
 623 public:
 624   JumpData(DataLayout* layout) : ProfileData(layout) {
 625     assert(layout->tag() == DataLayout::jump_data_tag ||
 626       layout->tag() == DataLayout::branch_data_tag ||
 627       layout->tag() == DataLayout::acmp_data_tag, "wrong type");
 628   }
 629 
 630   virtual bool is_JumpData() const { return true; }
 631 
 632   static int static_cell_count() {
 633     return jump_cell_count;
 634   }
 635 
 636   virtual int cell_count() const {
 637     return static_cell_count();
 638   }
 639 
 640   // Direct accessor
 641   uint taken() const {
 642     return uint_at(taken_off_set);
 643   }
 644 
 645   void set_taken(uint cnt) {
 646     set_uint_at(taken_off_set, cnt);
 647   }
 648 
 649   // Saturating counter
 650   uint inc_taken() {
 651     uint cnt = taken() + 1;
 652     // Did we wrap? Will compiler screw us??
 653     if (cnt == 0) cnt--;
 654     set_uint_at(taken_off_set, cnt);
 655     return cnt;
 656   }
 657 
 658   int displacement() const {
 659     return int_at(displacement_off_set);
 660   }
 661 
 662   // Code generation support
 663   static ByteSize taken_offset() {
 664     return cell_offset(taken_off_set);
 665   }
 666 
 667   static ByteSize displacement_offset() {
 668     return cell_offset(displacement_off_set);
 669   }
 670 
 671   // Specific initialization.
 672   void post_initialize(BytecodeStream* stream, MethodData* mdo);
 673 
 674   void print_data_on(outputStream* st, const char* extra = NULL) const;
 675 };
 676 
 677 // Entries in a ProfileData object to record types: it can either be
 678 // none (no profile), unknown (conflicting profile data) or a klass if
 679 // a single one is seen. Whether a null reference was seen is also
 680 // recorded. No counter is associated with the type and a single type
 681 // is tracked (unlike VirtualCallData).
 682 class TypeEntries {
 683 
 684 public:
 685 
 686   // A single cell is used to record information for a type:
 687   // - the cell is initialized to 0
 688   // - when a type is discovered it is stored in the cell
 689   // - bit zero of the cell is used to record whether a null reference
 690   // was encountered or not
 691   // - bit 1 is set to record a conflict in the type information
 692 
 693   enum {
 694     null_seen = 1,
 695     type_mask = ~null_seen,
 696     type_unknown = 2,
 697     status_bits = null_seen | type_unknown,
 698     type_klass_mask = ~status_bits
 699   };
 700 
 701   // what to initialize a cell to
 702   static intptr_t type_none() {
 703     return 0;
 704   }
 705 
 706   // null seen = bit 0 set?
 707   static bool was_null_seen(intptr_t v) {
 708     return (v & null_seen) != 0;
 709   }
 710 
 711   // conflicting type information = bit 1 set?
 712   static bool is_type_unknown(intptr_t v) {
 713     return (v & type_unknown) != 0;
 714   }
 715 
 716   // not type information yet = all bits cleared, ignoring bit 0?
 717   static bool is_type_none(intptr_t v) {
 718     return (v & type_mask) == 0;
 719   }
 720 
 721   // recorded type: cell without bit 0 and 1
 722   static intptr_t klass_part(intptr_t v) {
 723     intptr_t r = v & type_klass_mask;
 724     return r;
 725   }
 726 
 727   // type recorded
 728   static Klass* valid_klass(intptr_t k) {
 729     if (!is_type_none(k) &&
 730         !is_type_unknown(k)) {
 731       Klass* res = (Klass*)klass_part(k);
 732       assert(res != NULL, "invalid");
 733       return res;
 734     } else {
 735       return NULL;
 736     }
 737   }
 738 
 739   static intptr_t with_status(intptr_t k, intptr_t in) {
 740     return k | (in & status_bits);
 741   }
 742 
 743   static intptr_t with_status(Klass* k, intptr_t in) {
 744     return with_status((intptr_t)k, in);
 745   }
 746 
 747   static void print_klass(outputStream* st, intptr_t k);
 748 
 749 protected:
 750   // ProfileData object these entries are part of
 751   ProfileData* _pd;
 752   // offset within the ProfileData object where the entries start
 753   const int _base_off;
 754 
 755   TypeEntries(int base_off)
 756     : _pd(NULL), _base_off(base_off) {}
 757 
 758   void set_intptr_at(int index, intptr_t value) {
 759     _pd->set_intptr_at(index, value);
 760   }
 761 
 762   intptr_t intptr_at(int index) const {
 763     return _pd->intptr_at(index);
 764   }
 765 
 766 public:
 767   void set_profile_data(ProfileData* pd) {
 768     _pd = pd;
 769   }
 770 };
 771 
 772 // Type entries used for arguments passed at a call and parameters on
 773 // method entry. 2 cells per entry: one for the type encoded as in
 774 // TypeEntries and one initialized with the stack slot where the
 775 // profiled object is to be found so that the interpreter can locate
 776 // it quickly.
 777 class TypeStackSlotEntries : public TypeEntries {
 778 
 779 private:
 780   enum {
 781     stack_slot_entry,
 782     type_entry,
 783     per_arg_cell_count
 784   };
 785 
 786   // offset of cell for stack slot for entry i within ProfileData object
 787   int stack_slot_offset(int i) const {
 788     return _base_off + stack_slot_local_offset(i);
 789   }
 790 
 791   const int _number_of_entries;
 792 
 793   // offset of cell for type for entry i within ProfileData object
 794   int type_offset_in_cells(int i) const {
 795     return _base_off + type_local_offset(i);
 796   }
 797 
 798 public:
 799 
 800   TypeStackSlotEntries(int base_off, int nb_entries)
 801     : TypeEntries(base_off), _number_of_entries(nb_entries) {}
 802 
 803   static int compute_cell_count(Symbol* signature, bool include_receiver, int max);
 804 
 805   void post_initialize(Symbol* signature, bool has_receiver, bool include_receiver);
 806 
 807   int number_of_entries() const { return _number_of_entries; }
 808 
 809   // offset of cell for stack slot for entry i within this block of cells for a TypeStackSlotEntries
 810   static int stack_slot_local_offset(int i) {
 811     return i * per_arg_cell_count + stack_slot_entry;
 812   }
 813 
 814   // offset of cell for type for entry i within this block of cells for a TypeStackSlotEntries
 815   static int type_local_offset(int i) {
 816     return i * per_arg_cell_count + type_entry;
 817   }
 818 
 819   // stack slot for entry i
 820   uint stack_slot(int i) const {
 821     assert(i >= 0 && i < _number_of_entries, "oob");
 822     return _pd->uint_at(stack_slot_offset(i));
 823   }
 824 
 825   // set stack slot for entry i
 826   void set_stack_slot(int i, uint num) {
 827     assert(i >= 0 && i < _number_of_entries, "oob");
 828     _pd->set_uint_at(stack_slot_offset(i), num);
 829   }
 830 
 831   // type for entry i
 832   intptr_t type(int i) const {
 833     assert(i >= 0 && i < _number_of_entries, "oob");
 834     return _pd->intptr_at(type_offset_in_cells(i));
 835   }
 836 
 837   // set type for entry i
 838   void set_type(int i, intptr_t k) {
 839     assert(i >= 0 && i < _number_of_entries, "oob");
 840     _pd->set_intptr_at(type_offset_in_cells(i), k);
 841   }
 842 
 843   static ByteSize per_arg_size() {
 844     return in_ByteSize(per_arg_cell_count * DataLayout::cell_size);
 845   }
 846 
 847   static int per_arg_count() {
 848     return per_arg_cell_count;
 849   }
 850 
 851   ByteSize type_offset(int i) const {
 852     return DataLayout::cell_offset(type_offset_in_cells(i));
 853   }
 854 
 855   // GC support
 856   void clean_weak_klass_links(bool always_clean);
 857 
 858   void print_data_on(outputStream* st) const;
 859 };
 860 
 861 // Type entry used for return from a call. A single cell to record the
 862 // type.
 863 class SingleTypeEntry : public TypeEntries {
 864 
 865 private:
 866   enum {
 867     cell_count = 1
 868   };
 869 
 870 public:
 871   SingleTypeEntry(int base_off)
 872     : TypeEntries(base_off) {}
 873 
 874   void post_initialize() {
 875     set_type(type_none());
 876   }
 877 
 878   intptr_t type() const {
 879     return _pd->intptr_at(_base_off);
 880   }
 881 
 882   void set_type(intptr_t k) {
 883     _pd->set_intptr_at(_base_off, k);
 884   }
 885 
 886   static int static_cell_count() {
 887     return cell_count;
 888   }
 889 
 890   static ByteSize size() {
 891     return in_ByteSize(cell_count * DataLayout::cell_size);
 892   }
 893 
 894   ByteSize type_offset() {
 895     return DataLayout::cell_offset(_base_off);
 896   }
 897 
 898   // GC support
 899   void clean_weak_klass_links(bool always_clean);
 900 
 901   void print_data_on(outputStream* st) const;
 902 };
 903 
 904 // Entries to collect type information at a call: contains arguments
 905 // (TypeStackSlotEntries), a return type (SingleTypeEntry) and a
 906 // number of cells. Because the number of cells for the return type is
 907 // smaller than the number of cells for the type of an arguments, the
 908 // number of cells is used to tell how many arguments are profiled and
 909 // whether a return value is profiled. See has_arguments() and
 910 // has_return().
 911 class TypeEntriesAtCall {
 912 private:
 913   static int stack_slot_local_offset(int i) {
 914     return header_cell_count() + TypeStackSlotEntries::stack_slot_local_offset(i);
 915   }
 916 
 917   static int argument_type_local_offset(int i) {
 918     return header_cell_count() + TypeStackSlotEntries::type_local_offset(i);
 919   }
 920 
 921 public:
 922 
 923   static int header_cell_count() {
 924     return 1;
 925   }
 926 
 927   static int cell_count_local_offset() {
 928     return 0;
 929   }
 930 
 931   static int compute_cell_count(BytecodeStream* stream);
 932 
 933   static void initialize(DataLayout* dl, int base, int cell_count) {
 934     int off = base + cell_count_local_offset();
 935     dl->set_cell_at(off, cell_count - base - header_cell_count());
 936   }
 937 
 938   static bool arguments_profiling_enabled();
 939   static bool return_profiling_enabled();
 940 
 941   // Code generation support
 942   static ByteSize cell_count_offset() {
 943     return in_ByteSize(cell_count_local_offset() * DataLayout::cell_size);
 944   }
 945 
 946   static ByteSize args_data_offset() {
 947     return in_ByteSize(header_cell_count() * DataLayout::cell_size);
 948   }
 949 
 950   static ByteSize stack_slot_offset(int i) {
 951     return in_ByteSize(stack_slot_local_offset(i) * DataLayout::cell_size);
 952   }
 953 
 954   static ByteSize argument_type_offset(int i) {
 955     return in_ByteSize(argument_type_local_offset(i) * DataLayout::cell_size);
 956   }
 957 
 958   static ByteSize return_only_size() {
 959     return SingleTypeEntry::size() + in_ByteSize(header_cell_count() * DataLayout::cell_size);
 960   }
 961 
 962 };
 963 
 964 // CallTypeData
 965 //
 966 // A CallTypeData is used to access profiling information about a non
 967 // virtual call for which we collect type information about arguments
 968 // and return value.
 969 class CallTypeData : public CounterData {
 970 private:
 971   // entries for arguments if any
 972   TypeStackSlotEntries _args;
 973   // entry for return type if any
 974   SingleTypeEntry _ret;
 975 
 976   int cell_count_global_offset() const {
 977     return CounterData::static_cell_count() + TypeEntriesAtCall::cell_count_local_offset();
 978   }
 979 
 980   // number of cells not counting the header
 981   int cell_count_no_header() const {
 982     return uint_at(cell_count_global_offset());
 983   }
 984 
 985   void check_number_of_arguments(int total) {
 986     assert(number_of_arguments() == total, "should be set in DataLayout::initialize");
 987   }
 988 
 989 public:
 990   CallTypeData(DataLayout* layout) :
 991     CounterData(layout),
 992     _args(CounterData::static_cell_count()+TypeEntriesAtCall::header_cell_count(), number_of_arguments()),
 993     _ret(cell_count() - SingleTypeEntry::static_cell_count())
 994   {
 995     assert(layout->tag() == DataLayout::call_type_data_tag, "wrong type");
 996     // Some compilers (VC++) don't want this passed in member initialization list
 997     _args.set_profile_data(this);
 998     _ret.set_profile_data(this);
 999   }
1000 
1001   const TypeStackSlotEntries* args() const {
1002     assert(has_arguments(), "no profiling of arguments");
1003     return &_args;
1004   }
1005 
1006   const SingleTypeEntry* ret() const {
1007     assert(has_return(), "no profiling of return value");
1008     return &_ret;
1009   }
1010 
1011   virtual bool is_CallTypeData() const { return true; }
1012 
1013   static int static_cell_count() {
1014     return -1;
1015   }
1016 
1017   static int compute_cell_count(BytecodeStream* stream) {
1018     return CounterData::static_cell_count() + TypeEntriesAtCall::compute_cell_count(stream);
1019   }
1020 
1021   static void initialize(DataLayout* dl, int cell_count) {
1022     TypeEntriesAtCall::initialize(dl, CounterData::static_cell_count(), cell_count);
1023   }
1024 
1025   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1026 
1027   virtual int cell_count() const {
1028     return CounterData::static_cell_count() +
1029       TypeEntriesAtCall::header_cell_count() +
1030       int_at_unchecked(cell_count_global_offset());
1031   }
1032 
1033   int number_of_arguments() const {
1034     return cell_count_no_header() / TypeStackSlotEntries::per_arg_count();
1035   }
1036 
1037   void set_argument_type(int i, Klass* k) {
1038     assert(has_arguments(), "no arguments!");
1039     intptr_t current = _args.type(i);
1040     _args.set_type(i, TypeEntries::with_status(k, current));
1041   }
1042 
1043   void set_return_type(Klass* k) {
1044     assert(has_return(), "no return!");
1045     intptr_t current = _ret.type();
1046     _ret.set_type(TypeEntries::with_status(k, current));
1047   }
1048 
1049   // An entry for a return value takes less space than an entry for an
1050   // argument so if the number of cells exceeds the number of cells
1051   // needed for an argument, this object contains type information for
1052   // at least one argument.
1053   bool has_arguments() const {
1054     bool res = cell_count_no_header() >= TypeStackSlotEntries::per_arg_count();
1055     assert (!res || TypeEntriesAtCall::arguments_profiling_enabled(), "no profiling of arguments");
1056     return res;
1057   }
1058 
1059   // An entry for a return value takes less space than an entry for an
1060   // argument, so if the remainder of the number of cells divided by
1061   // the number of cells for an argument is not null, a return value
1062   // is profiled in this object.
1063   bool has_return() const {
1064     bool res = (cell_count_no_header() % TypeStackSlotEntries::per_arg_count()) != 0;
1065     assert (!res || TypeEntriesAtCall::return_profiling_enabled(), "no profiling of return values");
1066     return res;
1067   }
1068 
1069   // Code generation support
1070   static ByteSize args_data_offset() {
1071     return cell_offset(CounterData::static_cell_count()) + TypeEntriesAtCall::args_data_offset();
1072   }
1073 
1074   ByteSize argument_type_offset(int i) {
1075     return _args.type_offset(i);
1076   }
1077 
1078   ByteSize return_type_offset() {
1079     return _ret.type_offset();
1080   }
1081 
1082   // GC support
1083   virtual void clean_weak_klass_links(bool always_clean) {
1084     if (has_arguments()) {
1085       _args.clean_weak_klass_links(always_clean);
1086     }
1087     if (has_return()) {
1088       _ret.clean_weak_klass_links(always_clean);
1089     }
1090   }
1091 
1092   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1093 };
1094 
1095 // ReceiverTypeData
1096 //
1097 // A ReceiverTypeData is used to access profiling information about a
1098 // dynamic type check.  It consists of a counter which counts the total times
1099 // that the check is reached, and a series of (Klass*, count) pairs
1100 // which are used to store a type profile for the receiver of the check.
1101 class ReceiverTypeData : public CounterData {
1102   friend class VMStructs;
1103   friend class JVMCIVMStructs;
1104 protected:
1105   enum {
1106 #if INCLUDE_JVMCI
1107     // Description of the different counters
1108     // ReceiverTypeData for instanceof/checkcast/aastore:
1109     //   count is decremented for failed type checks
1110     //   JVMCI only: nonprofiled_count is incremented on type overflow
1111     // VirtualCallData for invokevirtual/invokeinterface:
1112     //   count is incremented on type overflow
1113     //   JVMCI only: nonprofiled_count is incremented on method overflow
1114 
1115     // JVMCI is interested in knowing the percentage of type checks involving a type not explicitly in the profile
1116     nonprofiled_count_off_set = counter_cell_count,
1117     receiver0_offset,
1118 #else
1119     receiver0_offset = counter_cell_count,
1120 #endif
1121     count0_offset,
1122     receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
1123   };
1124 
1125 public:
1126   ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
1127     assert(layout->tag() == DataLayout::receiver_type_data_tag ||
1128            layout->tag() == DataLayout::virtual_call_data_tag ||
1129            layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1130   }
1131 
1132   virtual bool is_ReceiverTypeData() const { return true; }
1133 
1134   static int static_cell_count() {
1135     return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count JVMCI_ONLY(+ 1);
1136   }
1137 
1138   virtual int cell_count() const {
1139     return static_cell_count();
1140   }
1141 
1142   // Direct accessors
1143   static uint row_limit() {
1144     return TypeProfileWidth;
1145   }
1146   static int receiver_cell_index(uint row) {
1147     return receiver0_offset + row * receiver_type_row_cell_count;
1148   }
1149   static int receiver_count_cell_index(uint row) {
1150     return count0_offset + row * receiver_type_row_cell_count;
1151   }
1152 
1153   Klass* receiver(uint row) const {
1154     assert(row < row_limit(), "oob");
1155 
1156     Klass* recv = (Klass*)intptr_at(receiver_cell_index(row));
1157     assert(recv == NULL || recv->is_klass(), "wrong type");
1158     return recv;
1159   }
1160 
1161   void set_receiver(uint row, Klass* k) {
1162     assert((uint)row < row_limit(), "oob");
1163     set_intptr_at(receiver_cell_index(row), (uintptr_t)k);
1164   }
1165 
1166   uint receiver_count(uint row) const {
1167     assert(row < row_limit(), "oob");
1168     return uint_at(receiver_count_cell_index(row));
1169   }
1170 
1171   void set_receiver_count(uint row, uint count) {
1172     assert(row < row_limit(), "oob");
1173     set_uint_at(receiver_count_cell_index(row), count);
1174   }
1175 
1176   void clear_row(uint row) {
1177     assert(row < row_limit(), "oob");
1178     // Clear total count - indicator of polymorphic call site.
1179     // The site may look like as monomorphic after that but
1180     // it allow to have more accurate profiling information because
1181     // there was execution phase change since klasses were unloaded.
1182     // If the site is still polymorphic then MDO will be updated
1183     // to reflect it. But it could be the case that the site becomes
1184     // only bimorphic. Then keeping total count not 0 will be wrong.
1185     // Even if we use monomorphic (when it is not) for compilation
1186     // we will only have trap, deoptimization and recompile again
1187     // with updated MDO after executing method in Interpreter.
1188     // An additional receiver will be recorded in the cleaned row
1189     // during next call execution.
1190     //
1191     // Note: our profiling logic works with empty rows in any slot.
1192     // We do sorting a profiling info (ciCallProfile) for compilation.
1193     //
1194     set_count(0);
1195     set_receiver(row, NULL);
1196     set_receiver_count(row, 0);
1197 #if INCLUDE_JVMCI
1198     if (!this->is_VirtualCallData()) {
1199       // if this is a ReceiverTypeData for JVMCI, the nonprofiled_count
1200       // must also be reset (see "Description of the different counters" above)
1201       set_nonprofiled_count(0);
1202     }
1203 #endif
1204   }
1205 
1206   // Code generation support
1207   static ByteSize receiver_offset(uint row) {
1208     return cell_offset(receiver_cell_index(row));
1209   }
1210   static ByteSize receiver_count_offset(uint row) {
1211     return cell_offset(receiver_count_cell_index(row));
1212   }
1213 #if INCLUDE_JVMCI
1214   static ByteSize nonprofiled_receiver_count_offset() {
1215     return cell_offset(nonprofiled_count_off_set);
1216   }
1217   uint nonprofiled_count() const {
1218     return uint_at(nonprofiled_count_off_set);
1219   }
1220   void set_nonprofiled_count(uint count) {
1221     set_uint_at(nonprofiled_count_off_set, count);
1222   }
1223 #endif // INCLUDE_JVMCI
1224   static ByteSize receiver_type_data_size() {
1225     return cell_offset(static_cell_count());
1226   }
1227 
1228   // GC support
1229   virtual void clean_weak_klass_links(bool always_clean);
1230 
1231   void print_receiver_data_on(outputStream* st) const;
1232   void print_data_on(outputStream* st, const char* extra = NULL) const;
1233 };
1234 
1235 // VirtualCallData
1236 //
1237 // A VirtualCallData is used to access profiling information about a
1238 // virtual call.  For now, it has nothing more than a ReceiverTypeData.
1239 class VirtualCallData : public ReceiverTypeData {
1240 public:
1241   VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
1242     assert(layout->tag() == DataLayout::virtual_call_data_tag ||
1243            layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1244   }
1245 
1246   virtual bool is_VirtualCallData() const { return true; }
1247 
1248   static int static_cell_count() {
1249     // At this point we could add more profile state, e.g., for arguments.
1250     // But for now it's the same size as the base record type.
1251     return ReceiverTypeData::static_cell_count();
1252   }
1253 
1254   virtual int cell_count() const {
1255     return static_cell_count();
1256   }
1257 
1258   // Direct accessors
1259   static ByteSize virtual_call_data_size() {
1260     return cell_offset(static_cell_count());
1261   }
1262 
1263   void print_method_data_on(outputStream* st) const NOT_JVMCI_RETURN;
1264   void print_data_on(outputStream* st, const char* extra = NULL) const;
1265 };
1266 
1267 // VirtualCallTypeData
1268 //
1269 // A VirtualCallTypeData is used to access profiling information about
1270 // a virtual call for which we collect type information about
1271 // arguments and return value.
1272 class VirtualCallTypeData : public VirtualCallData {
1273 private:
1274   // entries for arguments if any
1275   TypeStackSlotEntries _args;
1276   // entry for return type if any
1277   SingleTypeEntry _ret;
1278 
1279   int cell_count_global_offset() const {
1280     return VirtualCallData::static_cell_count() + TypeEntriesAtCall::cell_count_local_offset();
1281   }
1282 
1283   // number of cells not counting the header
1284   int cell_count_no_header() const {
1285     return uint_at(cell_count_global_offset());
1286   }
1287 
1288   void check_number_of_arguments(int total) {
1289     assert(number_of_arguments() == total, "should be set in DataLayout::initialize");
1290   }
1291 
1292 public:
1293   VirtualCallTypeData(DataLayout* layout) :
1294     VirtualCallData(layout),
1295     _args(VirtualCallData::static_cell_count()+TypeEntriesAtCall::header_cell_count(), number_of_arguments()),
1296     _ret(cell_count() - SingleTypeEntry::static_cell_count())
1297   {
1298     assert(layout->tag() == DataLayout::virtual_call_type_data_tag, "wrong type");
1299     // Some compilers (VC++) don't want this passed in member initialization list
1300     _args.set_profile_data(this);
1301     _ret.set_profile_data(this);
1302   }
1303 
1304   const TypeStackSlotEntries* args() const {
1305     assert(has_arguments(), "no profiling of arguments");
1306     return &_args;
1307   }
1308 
1309   const SingleTypeEntry* ret() const {
1310     assert(has_return(), "no profiling of return value");
1311     return &_ret;
1312   }
1313 
1314   virtual bool is_VirtualCallTypeData() const { return true; }
1315 
1316   static int static_cell_count() {
1317     return -1;
1318   }
1319 
1320   static int compute_cell_count(BytecodeStream* stream) {
1321     return VirtualCallData::static_cell_count() + TypeEntriesAtCall::compute_cell_count(stream);
1322   }
1323 
1324   static void initialize(DataLayout* dl, int cell_count) {
1325     TypeEntriesAtCall::initialize(dl, VirtualCallData::static_cell_count(), cell_count);
1326   }
1327 
1328   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1329 
1330   virtual int cell_count() const {
1331     return VirtualCallData::static_cell_count() +
1332       TypeEntriesAtCall::header_cell_count() +
1333       int_at_unchecked(cell_count_global_offset());
1334   }
1335 
1336   int number_of_arguments() const {
1337     return cell_count_no_header() / TypeStackSlotEntries::per_arg_count();
1338   }
1339 
1340   void set_argument_type(int i, Klass* k) {
1341     assert(has_arguments(), "no arguments!");
1342     intptr_t current = _args.type(i);
1343     _args.set_type(i, TypeEntries::with_status(k, current));
1344   }
1345 
1346   void set_return_type(Klass* k) {
1347     assert(has_return(), "no return!");
1348     intptr_t current = _ret.type();
1349     _ret.set_type(TypeEntries::with_status(k, current));
1350   }
1351 
1352   // An entry for a return value takes less space than an entry for an
1353   // argument, so if the remainder of the number of cells divided by
1354   // the number of cells for an argument is not null, a return value
1355   // is profiled in this object.
1356   bool has_return() const {
1357     bool res = (cell_count_no_header() % TypeStackSlotEntries::per_arg_count()) != 0;
1358     assert (!res || TypeEntriesAtCall::return_profiling_enabled(), "no profiling of return values");
1359     return res;
1360   }
1361 
1362   // An entry for a return value takes less space than an entry for an
1363   // argument so if the number of cells exceeds the number of cells
1364   // needed for an argument, this object contains type information for
1365   // at least one argument.
1366   bool has_arguments() const {
1367     bool res = cell_count_no_header() >= TypeStackSlotEntries::per_arg_count();
1368     assert (!res || TypeEntriesAtCall::arguments_profiling_enabled(), "no profiling of arguments");
1369     return res;
1370   }
1371 
1372   // Code generation support
1373   static ByteSize args_data_offset() {
1374     return cell_offset(VirtualCallData::static_cell_count()) + TypeEntriesAtCall::args_data_offset();
1375   }
1376 
1377   ByteSize argument_type_offset(int i) {
1378     return _args.type_offset(i);
1379   }
1380 
1381   ByteSize return_type_offset() {
1382     return _ret.type_offset();
1383   }
1384 
1385   // GC support
1386   virtual void clean_weak_klass_links(bool always_clean) {
1387     ReceiverTypeData::clean_weak_klass_links(always_clean);
1388     if (has_arguments()) {
1389       _args.clean_weak_klass_links(always_clean);
1390     }
1391     if (has_return()) {
1392       _ret.clean_weak_klass_links(always_clean);
1393     }
1394   }
1395 
1396   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1397 };
1398 
1399 // RetData
1400 //
1401 // A RetData is used to access profiling information for a ret bytecode.
1402 // It is composed of a count of the number of times that the ret has
1403 // been executed, followed by a series of triples of the form
1404 // (bci, count, di) which count the number of times that some bci was the
1405 // target of the ret and cache a corresponding data displacement.
1406 class RetData : public CounterData {
1407 protected:
1408   enum {
1409     bci0_offset = counter_cell_count,
1410     count0_offset,
1411     displacement0_offset,
1412     ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
1413   };
1414 
1415   void set_bci(uint row, int bci) {
1416     assert((uint)row < row_limit(), "oob");
1417     set_int_at(bci0_offset + row * ret_row_cell_count, bci);
1418   }
1419   void release_set_bci(uint row, int bci);
1420   void set_bci_count(uint row, uint count) {
1421     assert((uint)row < row_limit(), "oob");
1422     set_uint_at(count0_offset + row * ret_row_cell_count, count);
1423   }
1424   void set_bci_displacement(uint row, int disp) {
1425     set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
1426   }
1427 
1428 public:
1429   RetData(DataLayout* layout) : CounterData(layout) {
1430     assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
1431   }
1432 
1433   virtual bool is_RetData() const { return true; }
1434 
1435   enum {
1436     no_bci = -1 // value of bci when bci1/2 are not in use.
1437   };
1438 
1439   static int static_cell_count() {
1440     return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
1441   }
1442 
1443   virtual int cell_count() const {
1444     return static_cell_count();
1445   }
1446 
1447   static uint row_limit() {
1448     return BciProfileWidth;
1449   }
1450   static int bci_cell_index(uint row) {
1451     return bci0_offset + row * ret_row_cell_count;
1452   }
1453   static int bci_count_cell_index(uint row) {
1454     return count0_offset + row * ret_row_cell_count;
1455   }
1456   static int bci_displacement_cell_index(uint row) {
1457     return displacement0_offset + row * ret_row_cell_count;
1458   }
1459 
1460   // Direct accessors
1461   int bci(uint row) const {
1462     return int_at(bci_cell_index(row));
1463   }
1464   uint bci_count(uint row) const {
1465     return uint_at(bci_count_cell_index(row));
1466   }
1467   int bci_displacement(uint row) const {
1468     return int_at(bci_displacement_cell_index(row));
1469   }
1470 
1471   // Interpreter Runtime support
1472   address fixup_ret(int return_bci, MethodData* mdo);
1473 
1474   // Code generation support
1475   static ByteSize bci_offset(uint row) {
1476     return cell_offset(bci_cell_index(row));
1477   }
1478   static ByteSize bci_count_offset(uint row) {
1479     return cell_offset(bci_count_cell_index(row));
1480   }
1481   static ByteSize bci_displacement_offset(uint row) {
1482     return cell_offset(bci_displacement_cell_index(row));
1483   }
1484 
1485   // Specific initialization.
1486   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1487 
1488   void print_data_on(outputStream* st, const char* extra = NULL) const;
1489 };
1490 
1491 // BranchData
1492 //
1493 // A BranchData is used to access profiling data for a two-way branch.
1494 // It consists of taken and not_taken counts as well as a data displacement
1495 // for the taken case.
1496 class BranchData : public JumpData {
1497   friend class VMStructs;
1498   friend class JVMCIVMStructs;
1499 protected:
1500   enum {
1501     not_taken_off_set = jump_cell_count,
1502     branch_cell_count
1503   };
1504 
1505   void set_displacement(int displacement) {
1506     set_int_at(displacement_off_set, displacement);
1507   }
1508 
1509 public:
1510   BranchData(DataLayout* layout) : JumpData(layout) {
1511     assert(layout->tag() == DataLayout::branch_data_tag || layout->tag() == DataLayout::acmp_data_tag, "wrong type");
1512   }
1513 
1514   virtual bool is_BranchData() const { return true; }
1515 
1516   static int static_cell_count() {
1517     return branch_cell_count;
1518   }
1519 
1520   virtual int cell_count() const {
1521     return static_cell_count();
1522   }
1523 
1524   // Direct accessor
1525   uint not_taken() const {
1526     return uint_at(not_taken_off_set);
1527   }
1528 
1529   void set_not_taken(uint cnt) {
1530     set_uint_at(not_taken_off_set, cnt);
1531   }
1532 
1533   uint inc_not_taken() {
1534     uint cnt = not_taken() + 1;
1535     // Did we wrap? Will compiler screw us??
1536     if (cnt == 0) cnt--;
1537     set_uint_at(not_taken_off_set, cnt);
1538     return cnt;
1539   }
1540 
1541   // Code generation support
1542   static ByteSize not_taken_offset() {
1543     return cell_offset(not_taken_off_set);
1544   }
1545   static ByteSize branch_data_size() {
1546     return cell_offset(branch_cell_count);
1547   }
1548 
1549   // Specific initialization.
1550   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1551 
1552   void print_data_on(outputStream* st, const char* extra = NULL) const;
1553 };
1554 
1555 // ArrayData
1556 //
1557 // A ArrayData is a base class for accessing profiling data which does
1558 // not have a statically known size.  It consists of an array length
1559 // and an array start.
1560 class ArrayData : public ProfileData {
1561   friend class VMStructs;
1562   friend class JVMCIVMStructs;
1563 protected:
1564   friend class DataLayout;
1565 
1566   enum {
1567     array_len_off_set,
1568     array_start_off_set
1569   };
1570 
1571   uint array_uint_at(int index) const {
1572     int aindex = index + array_start_off_set;
1573     return uint_at(aindex);
1574   }
1575   int array_int_at(int index) const {
1576     int aindex = index + array_start_off_set;
1577     return int_at(aindex);
1578   }
1579   oop array_oop_at(int index) const {
1580     int aindex = index + array_start_off_set;
1581     return oop_at(aindex);
1582   }
1583   void array_set_int_at(int index, int value) {
1584     int aindex = index + array_start_off_set;
1585     set_int_at(aindex, value);
1586   }
1587 
1588   // Code generation support for subclasses.
1589   static ByteSize array_element_offset(int index) {
1590     return cell_offset(array_start_off_set + index);
1591   }
1592 
1593 public:
1594   ArrayData(DataLayout* layout) : ProfileData(layout) {}
1595 
1596   virtual bool is_ArrayData() const { return true; }
1597 
1598   static int static_cell_count() {
1599     return -1;
1600   }
1601 
1602   int array_len() const {
1603     return int_at_unchecked(array_len_off_set);
1604   }
1605 
1606   virtual int cell_count() const {
1607     return array_len() + 1;
1608   }
1609 
1610   // Code generation support
1611   static ByteSize array_len_offset() {
1612     return cell_offset(array_len_off_set);
1613   }
1614   static ByteSize array_start_offset() {
1615     return cell_offset(array_start_off_set);
1616   }
1617 };
1618 
1619 // MultiBranchData
1620 //
1621 // A MultiBranchData is used to access profiling information for
1622 // a multi-way branch (*switch bytecodes).  It consists of a series
1623 // of (count, displacement) pairs, which count the number of times each
1624 // case was taken and specify the data displacement for each branch target.
1625 class MultiBranchData : public ArrayData {
1626   friend class VMStructs;
1627   friend class JVMCIVMStructs;
1628 protected:
1629   enum {
1630     default_count_off_set,
1631     default_disaplacement_off_set,
1632     case_array_start
1633   };
1634   enum {
1635     relative_count_off_set,
1636     relative_displacement_off_set,
1637     per_case_cell_count
1638   };
1639 
1640   void set_default_displacement(int displacement) {
1641     array_set_int_at(default_disaplacement_off_set, displacement);
1642   }
1643   void set_displacement_at(int index, int displacement) {
1644     array_set_int_at(case_array_start +
1645                      index * per_case_cell_count +
1646                      relative_displacement_off_set,
1647                      displacement);
1648   }
1649 
1650 public:
1651   MultiBranchData(DataLayout* layout) : ArrayData(layout) {
1652     assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
1653   }
1654 
1655   virtual bool is_MultiBranchData() const { return true; }
1656 
1657   static int compute_cell_count(BytecodeStream* stream);
1658 
1659   int number_of_cases() const {
1660     int alen = array_len() - 2; // get rid of default case here.
1661     assert(alen % per_case_cell_count == 0, "must be even");
1662     return (alen / per_case_cell_count);
1663   }
1664 
1665   uint default_count() const {
1666     return array_uint_at(default_count_off_set);
1667   }
1668   int default_displacement() const {
1669     return array_int_at(default_disaplacement_off_set);
1670   }
1671 
1672   uint count_at(int index) const {
1673     return array_uint_at(case_array_start +
1674                          index * per_case_cell_count +
1675                          relative_count_off_set);
1676   }
1677   int displacement_at(int index) const {
1678     return array_int_at(case_array_start +
1679                         index * per_case_cell_count +
1680                         relative_displacement_off_set);
1681   }
1682 
1683   // Code generation support
1684   static ByteSize default_count_offset() {
1685     return array_element_offset(default_count_off_set);
1686   }
1687   static ByteSize default_displacement_offset() {
1688     return array_element_offset(default_disaplacement_off_set);
1689   }
1690   static ByteSize case_count_offset(int index) {
1691     return case_array_offset() +
1692            (per_case_size() * index) +
1693            relative_count_offset();
1694   }
1695   static ByteSize case_array_offset() {
1696     return array_element_offset(case_array_start);
1697   }
1698   static ByteSize per_case_size() {
1699     return in_ByteSize(per_case_cell_count) * cell_size;
1700   }
1701   static ByteSize relative_count_offset() {
1702     return in_ByteSize(relative_count_off_set) * cell_size;
1703   }
1704   static ByteSize relative_displacement_offset() {
1705     return in_ByteSize(relative_displacement_off_set) * cell_size;
1706   }
1707 
1708   // Specific initialization.
1709   void post_initialize(BytecodeStream* stream, MethodData* mdo);
1710 
1711   void print_data_on(outputStream* st, const char* extra = NULL) const;
1712 };
1713 
1714 class ArgInfoData : public ArrayData {
1715 
1716 public:
1717   ArgInfoData(DataLayout* layout) : ArrayData(layout) {
1718     assert(layout->tag() == DataLayout::arg_info_data_tag, "wrong type");
1719   }
1720 
1721   virtual bool is_ArgInfoData() const { return true; }
1722 
1723 
1724   int number_of_args() const {
1725     return array_len();
1726   }
1727 
1728   uint arg_modified(int arg) const {
1729     return array_uint_at(arg);
1730   }
1731 
1732   void set_arg_modified(int arg, uint val) {
1733     array_set_int_at(arg, val);
1734   }
1735 
1736   void print_data_on(outputStream* st, const char* extra = NULL) const;
1737 };
1738 
1739 // ParametersTypeData
1740 //
1741 // A ParametersTypeData is used to access profiling information about
1742 // types of parameters to a method
1743 class ParametersTypeData : public ArrayData {
1744 
1745 private:
1746   TypeStackSlotEntries _parameters;
1747 
1748   static int stack_slot_local_offset(int i) {
1749     assert_profiling_enabled();
1750     return array_start_off_set + TypeStackSlotEntries::stack_slot_local_offset(i);
1751   }
1752 
1753   static int type_local_offset(int i) {
1754     assert_profiling_enabled();
1755     return array_start_off_set + TypeStackSlotEntries::type_local_offset(i);
1756   }
1757 
1758   static bool profiling_enabled();
1759   static void assert_profiling_enabled() {
1760     assert(profiling_enabled(), "method parameters profiling should be on");
1761   }
1762 
1763 public:
1764   ParametersTypeData(DataLayout* layout) : ArrayData(layout), _parameters(1, number_of_parameters()) {
1765     assert(layout->tag() == DataLayout::parameters_type_data_tag, "wrong type");
1766     // Some compilers (VC++) don't want this passed in member initialization list
1767     _parameters.set_profile_data(this);
1768   }
1769 
1770   static int compute_cell_count(Method* m);
1771 
1772   virtual bool is_ParametersTypeData() const { return true; }
1773 
1774   virtual void post_initialize(BytecodeStream* stream, MethodData* mdo);
1775 
1776   int number_of_parameters() const {
1777     return array_len() / TypeStackSlotEntries::per_arg_count();
1778   }
1779 
1780   const TypeStackSlotEntries* parameters() const { return &_parameters; }
1781 
1782   uint stack_slot(int i) const {
1783     return _parameters.stack_slot(i);
1784   }
1785 
1786   void set_type(int i, Klass* k) {
1787     intptr_t current = _parameters.type(i);
1788     _parameters.set_type(i, TypeEntries::with_status((intptr_t)k, current));
1789   }
1790 
1791   virtual void clean_weak_klass_links(bool always_clean) {
1792     _parameters.clean_weak_klass_links(always_clean);
1793   }
1794 
1795   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1796 
1797   static ByteSize stack_slot_offset(int i) {
1798     return cell_offset(stack_slot_local_offset(i));
1799   }
1800 
1801   static ByteSize type_offset(int i) {
1802     return cell_offset(type_local_offset(i));
1803   }
1804 };
1805 
1806 // SpeculativeTrapData
1807 //
1808 // A SpeculativeTrapData is used to record traps due to type
1809 // speculation. It records the root of the compilation: that type
1810 // speculation is wrong in the context of one compilation (for
1811 // method1) doesn't mean it's wrong in the context of another one (for
1812 // method2). Type speculation could have more/different data in the
1813 // context of the compilation of method2 and it's worthwhile to try an
1814 // optimization that failed for compilation of method1 in the context
1815 // of compilation of method2.
1816 // Space for SpeculativeTrapData entries is allocated from the extra
1817 // data space in the MDO. If we run out of space, the trap data for
1818 // the ProfileData at that bci is updated.
1819 class SpeculativeTrapData : public ProfileData {
1820 protected:
1821   enum {
1822     speculative_trap_method,
1823 #ifndef _LP64
1824     // The size of the area for traps is a multiple of the header
1825     // size, 2 cells on 32 bits. Packed at the end of this area are
1826     // argument info entries (with tag
1827     // DataLayout::arg_info_data_tag). The logic in
1828     // MethodData::bci_to_extra_data() that guarantees traps don't
1829     // overflow over argument info entries assumes the size of a
1830     // SpeculativeTrapData is twice the header size. On 32 bits, a
1831     // SpeculativeTrapData must be 4 cells.
1832     padding,
1833 #endif
1834     speculative_trap_cell_count
1835   };
1836 public:
1837   SpeculativeTrapData(DataLayout* layout) : ProfileData(layout) {
1838     assert(layout->tag() == DataLayout::speculative_trap_data_tag, "wrong type");
1839   }
1840 
1841   virtual bool is_SpeculativeTrapData() const { return true; }
1842 
1843   static int static_cell_count() {
1844     return speculative_trap_cell_count;
1845   }
1846 
1847   virtual int cell_count() const {
1848     return static_cell_count();
1849   }
1850 
1851   // Direct accessor
1852   Method* method() const {
1853     return (Method*)intptr_at(speculative_trap_method);
1854   }
1855 
1856   void set_method(Method* m) {
1857     assert(!m->is_old(), "cannot add old methods");
1858     set_intptr_at(speculative_trap_method, (intptr_t)m);
1859   }
1860 
1861   static ByteSize method_offset() {
1862     return cell_offset(speculative_trap_method);
1863   }
1864 
1865   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1866 };
1867 
1868 class ArrayLoadStoreData : public ProfileData {
1869 private:
1870   enum {
1871     flat_array_flag = DataLayout::first_flag,
1872     null_free_array_flag = flat_array_flag + 1,
1873   };
1874 
1875   SingleTypeEntry _array;
1876   SingleTypeEntry _element;
1877 
1878 public:
1879   ArrayLoadStoreData(DataLayout* layout) :
1880     ProfileData(layout),
1881     _array(0),
1882     _element(SingleTypeEntry::static_cell_count()) {
1883     assert(layout->tag() == DataLayout::array_load_store_data_tag, "wrong type");
1884     _array.set_profile_data(this);
1885     _element.set_profile_data(this);
1886   }
1887 
1888   const SingleTypeEntry* array() const {
1889     return &_array;
1890   }
1891 
1892   const SingleTypeEntry* element() const {
1893     return &_element;
1894   }
1895 
1896   virtual bool is_ArrayLoadStoreData() const { return true; }
1897 
1898   static int static_cell_count() {
1899     return SingleTypeEntry::static_cell_count() * 2;
1900   }
1901 
1902   virtual int cell_count() const {
1903     return static_cell_count();
1904   }
1905 
1906   void set_flat_array() { set_flag_at(flat_array_flag); }
1907   bool flat_array() const { return flag_at(flat_array_flag); }
1908 
1909   void set_null_free_array() { set_flag_at(null_free_array_flag); }
1910   bool null_free_array() const { return flag_at(null_free_array_flag); }
1911 
1912   // Code generation support
1913   static int flat_array_byte_constant() {
1914     return flag_number_to_constant(flat_array_flag);
1915   }
1916 
1917   static int null_free_array_byte_constant() {
1918     return flag_number_to_constant(null_free_array_flag);
1919   }
1920 
1921   static ByteSize array_offset() {
1922     return cell_offset(0);
1923   }
1924 
1925   static ByteSize element_offset() {
1926     return cell_offset(SingleTypeEntry::static_cell_count());
1927   }
1928 
1929   virtual void clean_weak_klass_links(bool always_clean) {
1930     _array.clean_weak_klass_links(always_clean);
1931     _element.clean_weak_klass_links(always_clean);
1932   }
1933 
1934   static ByteSize array_load_store_data_size() {
1935     return cell_offset(static_cell_count());
1936   }
1937 
1938   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
1939 };
1940 
1941 class ACmpData : public BranchData {
1942 private:
1943   enum {
1944     left_inline_type_flag = DataLayout::first_flag,
1945     right_inline_type_flag
1946   };
1947 
1948   SingleTypeEntry _left;
1949   SingleTypeEntry _right;
1950 
1951 public:
1952   ACmpData(DataLayout* layout) :
1953     BranchData(layout),
1954     _left(BranchData::static_cell_count()),
1955     _right(BranchData::static_cell_count() + SingleTypeEntry::static_cell_count()) {
1956     assert(layout->tag() == DataLayout::acmp_data_tag, "wrong type");
1957     _left.set_profile_data(this);
1958     _right.set_profile_data(this);
1959   }
1960 
1961   const SingleTypeEntry* left() const {
1962     return &_left;
1963   }
1964 
1965   const SingleTypeEntry* right() const {
1966     return &_right;
1967   }
1968 
1969   virtual bool is_ACmpData() const { return true; }
1970 
1971   static int static_cell_count() {
1972     return BranchData::static_cell_count() + SingleTypeEntry::static_cell_count() * 2;
1973   }
1974 
1975   virtual int cell_count() const {
1976     return static_cell_count();
1977   }
1978 
1979   void set_left_inline_type() { set_flag_at(left_inline_type_flag); }
1980   bool left_inline_type() const { return flag_at(left_inline_type_flag); }
1981 
1982   void set_right_inline_type() { set_flag_at(right_inline_type_flag); }
1983   bool right_inline_type() const { return flag_at(right_inline_type_flag); }
1984 
1985   // Code generation support
1986   static int left_inline_type_byte_constant() {
1987     return flag_number_to_constant(left_inline_type_flag);
1988   }
1989 
1990   static int right_inline_type_byte_constant() {
1991     return flag_number_to_constant(right_inline_type_flag);
1992   }
1993 
1994   static ByteSize left_offset() {
1995     return cell_offset(BranchData::static_cell_count());
1996   }
1997 
1998   static ByteSize right_offset() {
1999     return cell_offset(BranchData::static_cell_count() + SingleTypeEntry::static_cell_count());
2000   }
2001 
2002   virtual void clean_weak_klass_links(bool always_clean) {
2003     _left.clean_weak_klass_links(always_clean);
2004     _right.clean_weak_klass_links(always_clean);
2005   }
2006 
2007   static ByteSize acmp_data_size() {
2008     return cell_offset(static_cell_count());
2009   }
2010 
2011   virtual void print_data_on(outputStream* st, const char* extra = NULL) const;
2012 };
2013 
2014 // MethodData*
2015 //
2016 // A MethodData* holds information which has been collected about
2017 // a method.  Its layout looks like this:
2018 //
2019 // -----------------------------
2020 // | header                    |
2021 // | klass                     |
2022 // -----------------------------
2023 // | method                    |
2024 // | size of the MethodData* |
2025 // -----------------------------
2026 // | Data entries...           |
2027 // |   (variable size)         |
2028 // |                           |
2029 // .                           .
2030 // .                           .
2031 // .                           .
2032 // |                           |
2033 // -----------------------------
2034 //
2035 // The data entry area is a heterogeneous array of DataLayouts. Each
2036 // DataLayout in the array corresponds to a specific bytecode in the
2037 // method.  The entries in the array are sorted by the corresponding
2038 // bytecode.  Access to the data is via resource-allocated ProfileData,
2039 // which point to the underlying blocks of DataLayout structures.
2040 //
2041 // During interpretation, if profiling in enabled, the interpreter
2042 // maintains a method data pointer (mdp), which points at the entry
2043 // in the array corresponding to the current bci.  In the course of
2044 // interpretation, when a bytecode is encountered that has profile data
2045 // associated with it, the entry pointed to by mdp is updated, then the
2046 // mdp is adjusted to point to the next appropriate DataLayout.  If mdp
2047 // is NULL to begin with, the interpreter assumes that the current method
2048 // is not (yet) being profiled.
2049 //
2050 // In MethodData* parlance, "dp" is a "data pointer", the actual address
2051 // of a DataLayout element.  A "di" is a "data index", the offset in bytes
2052 // from the base of the data entry array.  A "displacement" is the byte offset
2053 // in certain ProfileData objects that indicate the amount the mdp must be
2054 // adjusted in the event of a change in control flow.
2055 //
2056 
2057 class CleanExtraDataClosure : public StackObj {
2058 public:
2059   virtual bool is_live(Method* m) = 0;
2060 };
2061 
2062 
2063 #if INCLUDE_JVMCI
2064 // Encapsulates an encoded speculation reason. These are linked together in
2065 // a list that is atomically appended to during deoptimization. Entries are
2066 // never removed from the list.
2067 // @see jdk.vm.ci.hotspot.HotSpotSpeculationLog.HotSpotSpeculationEncoding
2068 class FailedSpeculation: public CHeapObj<mtCompiler> {
2069  private:
2070   // The length of HotSpotSpeculationEncoding.toByteArray(). The data itself
2071   // is an array embedded at the end of this object.
2072   int   _data_len;
2073 
2074   // Next entry in a linked list.
2075   FailedSpeculation* _next;
2076 
2077   FailedSpeculation(address data, int data_len);
2078 
2079   FailedSpeculation** next_adr() { return &_next; }
2080 
2081   // Placement new operator for inlining the speculation data into
2082   // the FailedSpeculation object.
2083   void* operator new(size_t size, size_t fs_size) throw();
2084 
2085  public:
2086   char* data()         { return (char*)(((address) this) + sizeof(FailedSpeculation)); }
2087   int data_len() const { return _data_len; }
2088   FailedSpeculation* next() const { return _next; }
2089 
2090   // Atomically appends a speculation from nm to the list whose head is at (*failed_speculations_address).
2091   // Returns false if the FailedSpeculation object could not be allocated.
2092   static bool add_failed_speculation(nmethod* nm, FailedSpeculation** failed_speculations_address, address speculation, int speculation_len);
2093 
2094   // Frees all entries in the linked list whose head is at (*failed_speculations_address).
2095   static void free_failed_speculations(FailedSpeculation** failed_speculations_address);
2096 };
2097 #endif
2098 
2099 class ciMethodData;
2100 
2101 class MethodData : public Metadata {
2102   friend class VMStructs;
2103   friend class JVMCIVMStructs;
2104 private:
2105   friend class ProfileData;
2106   friend class TypeEntriesAtCall;
2107   friend class ciMethodData;
2108 
2109   // If you add a new field that points to any metaspace object, you
2110   // must add this field to MethodData::metaspace_pointers_do().
2111 
2112   // Back pointer to the Method*
2113   Method* _method;
2114 
2115   // Size of this oop in bytes
2116   int _size;
2117 
2118   // Cached hint for bci_to_dp and bci_to_data
2119   int _hint_di;
2120 
2121   Mutex _extra_data_lock;
2122 
2123   MethodData(const methodHandle& method);
2124 public:
2125   static MethodData* allocate(ClassLoaderData* loader_data, const methodHandle& method, TRAPS);
2126 
2127   virtual bool is_methodData() const { return true; }
2128   void initialize();
2129 
2130   // Whole-method sticky bits and flags
2131   enum {
2132     _trap_hist_limit    = Deoptimization::Reason_TRAP_HISTORY_LENGTH,
2133     _trap_hist_mask     = max_jubyte,
2134     _extra_data_count   = 4     // extra DataLayout headers, for trap history
2135   }; // Public flag values
2136 
2137   // Compiler-related counters.
2138   class CompilerCounters {
2139     friend class VMStructs;
2140     friend class JVMCIVMStructs;
2141 
2142     uint _nof_decompiles;             // count of all nmethod removals
2143     uint _nof_overflow_recompiles;    // recompile count, excluding recomp. bits
2144     uint _nof_overflow_traps;         // trap count, excluding _trap_hist
2145     union {
2146       intptr_t _align;
2147       // JVMCI separates trap history for OSR compilations from normal compilations
2148       u1 _array[JVMCI_ONLY(2 *) MethodData::_trap_hist_limit];
2149     } _trap_hist;
2150 
2151   public:
2152     CompilerCounters() : _nof_decompiles(0), _nof_overflow_recompiles(0), _nof_overflow_traps(0) {
2153 #ifndef ZERO
2154       // Some Zero platforms do not have expected alignment, and do not use
2155       // this code. static_assert would still fire and fail for them.
2156       static_assert(sizeof(_trap_hist) % HeapWordSize == 0, "align");
2157 #endif
2158       uint size_in_words = sizeof(_trap_hist) / HeapWordSize;
2159       Copy::zero_to_words((HeapWord*) &_trap_hist, size_in_words);
2160     }
2161 
2162     // Return (uint)-1 for overflow.
2163     uint trap_count(int reason) const {
2164       assert((uint)reason < ARRAY_SIZE(_trap_hist._array), "oob");
2165       return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
2166     }
2167 
2168     uint inc_trap_count(int reason) {
2169       // Count another trap, anywhere in this method.
2170       assert(reason >= 0, "must be single trap");
2171       assert((uint)reason < ARRAY_SIZE(_trap_hist._array), "oob");
2172       uint cnt1 = 1 + _trap_hist._array[reason];
2173       if ((cnt1 & _trap_hist_mask) != 0) {  // if no counter overflow...
2174         _trap_hist._array[reason] = cnt1;
2175         return cnt1;
2176       } else {
2177         return _trap_hist_mask + (++_nof_overflow_traps);
2178       }
2179     }
2180 
2181     uint overflow_trap_count() const {
2182       return _nof_overflow_traps;
2183     }
2184     uint overflow_recompile_count() const {
2185       return _nof_overflow_recompiles;
2186     }
2187     uint inc_overflow_recompile_count() {
2188       return ++_nof_overflow_recompiles;
2189     }
2190     uint decompile_count() const {
2191       return _nof_decompiles;
2192     }
2193     uint inc_decompile_count() {
2194       return ++_nof_decompiles;
2195     }
2196 
2197     // Support for code generation
2198     static ByteSize trap_history_offset() {
2199       return byte_offset_of(CompilerCounters, _trap_hist._array);
2200     }
2201   };
2202 
2203 private:
2204   CompilerCounters _compiler_counters;
2205 
2206   // Support for interprocedural escape analysis, from Thomas Kotzmann.
2207   intx              _eflags;          // flags on escape information
2208   intx              _arg_local;       // bit set of non-escaping arguments
2209   intx              _arg_stack;       // bit set of stack-allocatable arguments
2210   intx              _arg_returned;    // bit set of returned arguments
2211 
2212   int               _creation_mileage; // method mileage at MDO creation
2213 
2214   // How many invocations has this MDO seen?
2215   // These counters are used to determine the exact age of MDO.
2216   // We need those because in tiered a method can be concurrently
2217   // executed at different levels.
2218   InvocationCounter _invocation_counter;
2219   // Same for backedges.
2220   InvocationCounter _backedge_counter;
2221   // Counter values at the time profiling started.
2222   int               _invocation_counter_start;
2223   int               _backedge_counter_start;
2224   uint              _tenure_traps;
2225   int               _invoke_mask;      // per-method Tier0InvokeNotifyFreqLog
2226   int               _backedge_mask;    // per-method Tier0BackedgeNotifyFreqLog
2227 
2228 #if INCLUDE_RTM_OPT
2229   // State of RTM code generation during compilation of the method
2230   int               _rtm_state;
2231 #endif
2232 
2233   // Number of loops and blocks is computed when compiling the first
2234   // time with C1. It is used to determine if method is trivial.
2235   short             _num_loops;
2236   short             _num_blocks;
2237   // Does this method contain anything worth profiling?
2238   enum WouldProfile {unknown, no_profile, profile};
2239   WouldProfile      _would_profile;
2240 
2241 #if INCLUDE_JVMCI
2242   // Support for HotSpotMethodData.setCompiledIRSize(int)
2243   int                _jvmci_ir_size;
2244   FailedSpeculation* _failed_speculations;
2245 #endif
2246 
2247   // Size of _data array in bytes.  (Excludes header and extra_data fields.)
2248   int _data_size;
2249 
2250   // data index for the area dedicated to parameters. -1 if no
2251   // parameter profiling.
2252   enum { no_parameters = -2, parameters_uninitialized = -1 };
2253   int _parameters_type_data_di;
2254 
2255   // Beginning of the data entries
2256   intptr_t _data[1];
2257 
2258   // Helper for size computation
2259   static int compute_data_size(BytecodeStream* stream);
2260   static int bytecode_cell_count(Bytecodes::Code code);
2261   static bool is_speculative_trap_bytecode(Bytecodes::Code code);
2262   enum { no_profile_data = -1, variable_cell_count = -2 };
2263 
2264   // Helper for initialization
2265   DataLayout* data_layout_at(int data_index) const {
2266     assert(data_index % sizeof(intptr_t) == 0, "unaligned");
2267     return (DataLayout*) (((address)_data) + data_index);
2268   }
2269 
2270   // Initialize an individual data segment.  Returns the size of
2271   // the segment in bytes.
2272   int initialize_data(BytecodeStream* stream, int data_index);
2273 
2274   // Helper for data_at
2275   DataLayout* limit_data_position() const {
2276     return data_layout_at(_data_size);
2277   }
2278   bool out_of_bounds(int data_index) const {
2279     return data_index >= data_size();
2280   }
2281 
2282   // Give each of the data entries a chance to perform specific
2283   // data initialization.
2284   void post_initialize(BytecodeStream* stream);
2285 
2286   // hint accessors
2287   int      hint_di() const  { return _hint_di; }
2288   void set_hint_di(int di)  {
2289     assert(!out_of_bounds(di), "hint_di out of bounds");
2290     _hint_di = di;
2291   }
2292 
2293   DataLayout* data_layout_before(int bci) {
2294     // avoid SEGV on this edge case
2295     if (data_size() == 0)
2296       return NULL;
2297     DataLayout* layout = data_layout_at(hint_di());
2298     if (layout->bci() <= bci)
2299       return layout;
2300     return data_layout_at(first_di());
2301   }
2302 
2303   // What is the index of the first data entry?
2304   int first_di() const { return 0; }
2305 
2306   ProfileData* bci_to_extra_data_helper(int bci, Method* m, DataLayout*& dp, bool concurrent);
2307   // Find or create an extra ProfileData:
2308   ProfileData* bci_to_extra_data(int bci, Method* m, bool create_if_missing);
2309 
2310   // return the argument info cell
2311   ArgInfoData *arg_info();
2312 
2313   enum {
2314     no_type_profile = 0,
2315     type_profile_jsr292 = 1,
2316     type_profile_all = 2
2317   };
2318 
2319   static bool profile_jsr292(const methodHandle& m, int bci);
2320   static bool profile_unsafe(const methodHandle& m, int bci);
2321   static bool profile_memory_access(const methodHandle& m, int bci);
2322   static int profile_arguments_flag();
2323   static bool profile_all_arguments();
2324   static bool profile_arguments_for_invoke(const methodHandle& m, int bci);
2325   static int profile_return_flag();
2326   static bool profile_all_return();
2327   static bool profile_return_for_invoke(const methodHandle& m, int bci);
2328   static int profile_parameters_flag();
2329   static bool profile_parameters_jsr292_only();
2330   static bool profile_all_parameters();
2331 
2332   void clean_extra_data_helper(DataLayout* dp, int shift, bool reset = false);
2333   void verify_extra_data_clean(CleanExtraDataClosure* cl);
2334 
2335 public:
2336   void clean_extra_data(CleanExtraDataClosure* cl);
2337 
2338   static int header_size() {
2339     return sizeof(MethodData)/wordSize;
2340   }
2341 
2342   // Compute the size of a MethodData* before it is created.
2343   static int compute_allocation_size_in_bytes(const methodHandle& method);
2344   static int compute_allocation_size_in_words(const methodHandle& method);
2345   static int compute_extra_data_count(int data_size, int empty_bc_count, bool needs_speculative_traps);
2346 
2347   // Determine if a given bytecode can have profile information.
2348   static bool bytecode_has_profile(Bytecodes::Code code) {
2349     return bytecode_cell_count(code) != no_profile_data;
2350   }
2351 
2352   // reset into original state
2353   void init();
2354 
2355   // My size
2356   int size_in_bytes() const { return _size; }
2357   int size() const    { return align_metadata_size(align_up(_size, BytesPerWord)/BytesPerWord); }
2358 
2359   int      creation_mileage() const { return _creation_mileage; }
2360   void set_creation_mileage(int x)  { _creation_mileage = x; }
2361 
2362   int invocation_count() {
2363     if (invocation_counter()->carry()) {
2364       return InvocationCounter::count_limit;
2365     }
2366     return invocation_counter()->count();
2367   }
2368   int backedge_count() {
2369     if (backedge_counter()->carry()) {
2370       return InvocationCounter::count_limit;
2371     }
2372     return backedge_counter()->count();
2373   }
2374 
2375   int invocation_count_start() {
2376     if (invocation_counter()->carry()) {
2377       return 0;
2378     }
2379     return _invocation_counter_start;
2380   }
2381 
2382   int backedge_count_start() {
2383     if (backedge_counter()->carry()) {
2384       return 0;
2385     }
2386     return _backedge_counter_start;
2387   }
2388 
2389   int invocation_count_delta() { return invocation_count() - invocation_count_start(); }
2390   int backedge_count_delta()   { return backedge_count()   - backedge_count_start();   }
2391 
2392   void reset_start_counters() {
2393     _invocation_counter_start = invocation_count();
2394     _backedge_counter_start = backedge_count();
2395   }
2396 
2397   InvocationCounter* invocation_counter()     { return &_invocation_counter; }
2398   InvocationCounter* backedge_counter()       { return &_backedge_counter;   }
2399 
2400 #if INCLUDE_JVMCI
2401   FailedSpeculation** get_failed_speculations_address() {
2402     return &_failed_speculations;
2403   }
2404 #endif
2405 
2406 #if INCLUDE_RTM_OPT
2407   int rtm_state() const {
2408     return _rtm_state;
2409   }
2410   void set_rtm_state(RTMState rstate) {
2411     _rtm_state = (int)rstate;
2412   }
2413   void atomic_set_rtm_state(RTMState rstate) {
2414     Atomic::store(&_rtm_state, (int)rstate);
2415   }
2416 
2417   static int rtm_state_offset_in_bytes() {
2418     return offset_of(MethodData, _rtm_state);
2419   }
2420 #endif
2421 
2422   void set_would_profile(bool p)              { _would_profile = p ? profile : no_profile; }
2423   bool would_profile() const                  { return _would_profile != no_profile; }
2424 
2425   int num_loops() const                       { return _num_loops;  }
2426   void set_num_loops(int n)                   { _num_loops = n;     }
2427   int num_blocks() const                      { return _num_blocks; }
2428   void set_num_blocks(int n)                  { _num_blocks = n;    }
2429 
2430   bool is_mature() const;  // consult mileage and ProfileMaturityPercentage
2431   static int mileage_of(Method* m);
2432 
2433   // Support for interprocedural escape analysis, from Thomas Kotzmann.
2434   enum EscapeFlag {
2435     estimated    = 1 << 0,
2436     return_local = 1 << 1,
2437     return_allocated = 1 << 2,
2438     allocated_escapes = 1 << 3,
2439     unknown_modified = 1 << 4
2440   };
2441 
2442   intx eflags()                                  { return _eflags; }
2443   intx arg_local()                               { return _arg_local; }
2444   intx arg_stack()                               { return _arg_stack; }
2445   intx arg_returned()                            { return _arg_returned; }
2446   uint arg_modified(int a)                       { ArgInfoData *aid = arg_info();
2447                                                    assert(aid != NULL, "arg_info must be not null");
2448                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
2449                                                    return aid->arg_modified(a); }
2450 
2451   void set_eflags(intx v)                        { _eflags = v; }
2452   void set_arg_local(intx v)                     { _arg_local = v; }
2453   void set_arg_stack(intx v)                     { _arg_stack = v; }
2454   void set_arg_returned(intx v)                  { _arg_returned = v; }
2455   void set_arg_modified(int a, uint v)           { ArgInfoData *aid = arg_info();
2456                                                    assert(aid != NULL, "arg_info must be not null");
2457                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
2458                                                    aid->set_arg_modified(a, v); }
2459 
2460   void clear_escape_info()                       { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
2461 
2462   // Location and size of data area
2463   address data_base() const {
2464     return (address) _data;
2465   }
2466   int data_size() const {
2467     return _data_size;
2468   }
2469 
2470   int parameters_size_in_bytes() const {
2471     ParametersTypeData* param = parameters_type_data();
2472     return param == NULL ? 0 : param->size_in_bytes();
2473   }
2474 
2475   // Accessors
2476   Method* method() const { return _method; }
2477 
2478   // Get the data at an arbitrary (sort of) data index.
2479   ProfileData* data_at(int data_index) const;
2480 
2481   // Walk through the data in order.
2482   ProfileData* first_data() const { return data_at(first_di()); }
2483   ProfileData* next_data(ProfileData* current) const;
2484   DataLayout*  next_data_layout(DataLayout* current) const;
2485   bool is_valid(ProfileData* current) const { return current != NULL; }
2486   bool is_valid(DataLayout*  current) const { return current != NULL; }
2487 
2488   // Convert a dp (data pointer) to a di (data index).
2489   int dp_to_di(address dp) const {
2490     return dp - ((address)_data);
2491   }
2492 
2493   // bci to di/dp conversion.
2494   address bci_to_dp(int bci);
2495   int bci_to_di(int bci) {
2496     return dp_to_di(bci_to_dp(bci));
2497   }
2498 
2499   // Get the data at an arbitrary bci, or NULL if there is none.
2500   ProfileData* bci_to_data(int bci);
2501 
2502   // Same, but try to create an extra_data record if one is needed:
2503   ProfileData* allocate_bci_to_data(int bci, Method* m) {
2504     ProfileData* data = NULL;
2505     // If m not NULL, try to allocate a SpeculativeTrapData entry
2506     if (m == NULL) {
2507       data = bci_to_data(bci);
2508     }
2509     if (data != NULL) {
2510       return data;
2511     }
2512     data = bci_to_extra_data(bci, m, true);
2513     if (data != NULL) {
2514       return data;
2515     }
2516     // If SpeculativeTrapData allocation fails try to allocate a
2517     // regular entry
2518     data = bci_to_data(bci);
2519     if (data != NULL) {
2520       return data;
2521     }
2522     return bci_to_extra_data(bci, NULL, true);
2523   }
2524 
2525   // Add a handful of extra data records, for trap tracking.
2526   DataLayout* extra_data_base() const  { return limit_data_position(); }
2527   DataLayout* extra_data_limit() const { return (DataLayout*)((address)this + size_in_bytes()); }
2528   DataLayout* args_data_limit() const  { return (DataLayout*)((address)this + size_in_bytes() -
2529                                                               parameters_size_in_bytes()); }
2530   int extra_data_size() const          { return (address)extra_data_limit() - (address)extra_data_base(); }
2531   static DataLayout* next_extra(DataLayout* dp);
2532 
2533   // Return (uint)-1 for overflow.
2534   uint trap_count(int reason) const {
2535     return _compiler_counters.trap_count(reason);
2536   }
2537   // For loops:
2538   static uint trap_reason_limit() { return _trap_hist_limit; }
2539   static uint trap_count_limit()  { return _trap_hist_mask; }
2540   uint inc_trap_count(int reason) {
2541     return _compiler_counters.inc_trap_count(reason);
2542   }
2543 
2544   uint overflow_trap_count() const {
2545     return _compiler_counters.overflow_trap_count();
2546   }
2547   uint overflow_recompile_count() const {
2548     return _compiler_counters.overflow_recompile_count();
2549   }
2550   uint inc_overflow_recompile_count() {
2551     return _compiler_counters.inc_overflow_recompile_count();
2552   }
2553   uint decompile_count() const {
2554     return _compiler_counters.decompile_count();
2555   }
2556   uint inc_decompile_count() {
2557     uint dec_count = _compiler_counters.inc_decompile_count();
2558     if (dec_count > (uint)PerMethodRecompilationCutoff) {
2559       method()->set_not_compilable("decompile_count > PerMethodRecompilationCutoff", CompLevel_full_optimization);
2560     }
2561     return dec_count;
2562   }
2563   uint tenure_traps() const {
2564     return _tenure_traps;
2565   }
2566   void inc_tenure_traps() {
2567     _tenure_traps += 1;
2568   }
2569 
2570   // Return pointer to area dedicated to parameters in MDO
2571   ParametersTypeData* parameters_type_data() const {
2572     assert(_parameters_type_data_di != parameters_uninitialized, "called too early");
2573     return _parameters_type_data_di != no_parameters ? data_layout_at(_parameters_type_data_di)->data_in()->as_ParametersTypeData() : NULL;
2574   }
2575 
2576   int parameters_type_data_di() const {
2577     assert(_parameters_type_data_di != parameters_uninitialized && _parameters_type_data_di != no_parameters, "no args type data");
2578     return _parameters_type_data_di;
2579   }
2580 
2581   // Support for code generation
2582   static ByteSize data_offset() {
2583     return byte_offset_of(MethodData, _data[0]);
2584   }
2585 
2586   static ByteSize trap_history_offset() {
2587     return byte_offset_of(MethodData, _compiler_counters) + CompilerCounters::trap_history_offset();
2588   }
2589 
2590   static ByteSize invocation_counter_offset() {
2591     return byte_offset_of(MethodData, _invocation_counter);
2592   }
2593 
2594   static ByteSize backedge_counter_offset() {
2595     return byte_offset_of(MethodData, _backedge_counter);
2596   }
2597 
2598   static ByteSize invoke_mask_offset() {
2599     return byte_offset_of(MethodData, _invoke_mask);
2600   }
2601 
2602   static ByteSize backedge_mask_offset() {
2603     return byte_offset_of(MethodData, _backedge_mask);
2604   }
2605 
2606   static ByteSize parameters_type_data_di_offset() {
2607     return byte_offset_of(MethodData, _parameters_type_data_di);
2608   }
2609 
2610   virtual void metaspace_pointers_do(MetaspaceClosure* iter);
2611   virtual MetaspaceObj::Type type() const { return MethodDataType; }
2612 
2613   // Deallocation support - no metaspace pointer fields to deallocate
2614   void deallocate_contents(ClassLoaderData* loader_data) {}
2615 
2616   // GC support
2617   void set_size(int object_size_in_bytes) { _size = object_size_in_bytes; }
2618 
2619   // Printing
2620   void print_on      (outputStream* st) const;
2621   void print_value_on(outputStream* st) const;
2622 
2623   // printing support for method data
2624   void print_data_on(outputStream* st) const;
2625 
2626   const char* internal_name() const { return "{method data}"; }
2627 
2628   // verification
2629   void verify_on(outputStream* st);
2630   void verify_data_on(outputStream* st);
2631 
2632   static bool profile_parameters_for_method(const methodHandle& m);
2633   static bool profile_arguments();
2634   static bool profile_arguments_jsr292_only();
2635   static bool profile_return();
2636   static bool profile_parameters();
2637   static bool profile_return_jsr292_only();
2638 
2639   void clean_method_data(bool always_clean);
2640   void clean_weak_method_links();
2641   Mutex* extra_data_lock() { return &_extra_data_lock; }
2642 };
2643 
2644 #endif // SHARE_OOPS_METHODDATA_HPP