jdk8-mips64-public/hotspot: src/share/vm/oops/methodDataOop.hpp@e1162778c1c8 (annotated)

src/share/vm/oops/methodDataOop.hpp@e1162778c1c8 (annotated)

src/share/vm/oops/methodDataOop.hpp

Thu, 07 Apr 2011 09:53:20 -0700

author: johnc
date: Thu, 07 Apr 2011 09:53:20 -0700
changeset 2781: e1162778c1c8
parent 2615: f767174aac14
child 2877: bad7ecd0b6ed
permissions: -rw-r--r--

7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes

 /*
  * Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #ifndef SHARE_VM_OOPS_METHODDATAOOP_HPP
 #define SHARE_VM_OOPS_METHODDATAOOP_HPP
 #include "interpreter/bytecodes.hpp"
 #include "memory/universe.hpp"
 #include "oops/methodOop.hpp"
 #include "oops/oop.hpp"
 #include "runtime/orderAccess.hpp"
 class BytecodeStream;
 // The MethodData object collects counts and other profile information
 // during zeroth-tier (interpretive) and first-tier execution.
 // The profile is used later by compilation heuristics.  Some heuristics
 // enable use of aggressive (or "heroic") optimizations.  An aggressive
 // optimization often has a down-side, a corner case that it handles
 // poorly, but which is thought to be rare.  The profile provides
 // evidence of this rarity for a given method or even BCI.  It allows
 // the compiler to back out of the optimization at places where it
 // has historically been a poor choice.  Other heuristics try to use
 // specific information gathered about types observed at a given site.
 //
 // All data in the profile is approximate.  It is expected to be accurate
 // on the whole, but the system expects occasional inaccuraces, due to
 // counter overflow, multiprocessor races during data collection, space
 // limitations, missing MDO blocks, etc.  Bad or missing data will degrade
 // optimization quality but will not affect correctness.  Also, each MDO
 // is marked with its birth-date ("creation_mileage") which can be used
 // to assess the quality ("maturity") of its data.
 //
 // Short (<32-bit) counters are designed to overflow to a known "saturated"
 // state.  Also, certain recorded per-BCI events are given one-bit counters
 // which overflow to a saturated state which applied to all counters at
 // that BCI.  In other words, there is a small lattice which approximates
 // the ideal of an infinite-precision counter for each event at each BCI,
 // and the lattice quickly "bottoms out" in a state where all counters
 // are taken to be indefinitely large.
 //
 // The reader will find many data races in profile gathering code, starting
 // with invocation counter incrementation.  None of these races harm correct
 // execution of the compiled code.
 // forward decl
 class ProfileData;
 // DataLayout
 //
 // Overlay for generic profiling data.
 class DataLayout VALUE_OBJ_CLASS_SPEC {
 private:
   // Every data layout begins with a header.  This header
   // contains a tag, which is used to indicate the size/layout
   // of the data, 4 bits of flags, which can be used in any way,
   // 4 bits of trap history (none/one reason/many reasons),
   // and a bci, which is used to tie this piece of data to a
   // specific bci in the bytecodes.
   union {
     intptr_t _bits;
     struct {
       u1 _tag;
       u1 _flags;
       u2 _bci;
     } _struct;
   } _header;
   // The data layout has an arbitrary number of cells, each sized
   // to accomodate a pointer or an integer.
   intptr_t _cells[1];
   // Some types of data layouts need a length field.
   static bool needs_array_len(u1 tag);
 public:
   enum {
     counter_increment = 1
   };
   enum {
     cell_size = sizeof(intptr_t)
   };
   // Tag values
   enum {
     no_tag,
     bit_data_tag,
     counter_data_tag,
     jump_data_tag,
     receiver_type_data_tag,
     virtual_call_data_tag,
     ret_data_tag,
     branch_data_tag,
     multi_branch_data_tag,
     arg_info_data_tag
   };
   enum {
     // The _struct._flags word is formatted as [trap_state:4 | flags:4].
     // The trap state breaks down further as [recompile:1 | reason:3].
     // This further breakdown is defined in deoptimization.cpp.
     // See Deoptimization::trap_state_reason for an assert that
     // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
     //
     // The trap_state is collected only if ProfileTraps is true.
     trap_bits = 1+3,  // 3: enough to distinguish [0..Reason_RECORDED_LIMIT].
     trap_shift = BitsPerByte - trap_bits,
     trap_mask = right_n_bits(trap_bits),
     trap_mask_in_place = (trap_mask << trap_shift),
     flag_limit = trap_shift,
     flag_mask = right_n_bits(flag_limit),
     first_flag = 0
   };
   // Size computation
   static int header_size_in_bytes() {
     return cell_size;
   }
   static int header_size_in_cells() {
     return 1;
   }
   static int compute_size_in_bytes(int cell_count) {
     return header_size_in_bytes() + cell_count * cell_size;
   }
   // Initialization
   void initialize(u1 tag, u2 bci, int cell_count);
   // Accessors
   u1 tag() {
     return _header._struct._tag;
   }
   // Return a few bits of trap state.  Range is [0..trap_mask].
   // The state tells if traps with zero, one, or many reasons have occurred.
   // It also tells whether zero or many recompilations have occurred.
   // The associated trap histogram in the MDO itself tells whether
   // traps are common or not.  If a BCI shows that a trap X has
   // occurred, and the MDO shows N occurrences of X, we make the
   // simplifying assumption that all N occurrences can be blamed
   // on that BCI.
   int trap_state() {
     return ((_header._struct._flags >> trap_shift) & trap_mask);
   }
   void set_trap_state(int new_state) {
     assert(ProfileTraps, "used only under +ProfileTraps");
     uint old_flags = (_header._struct._flags & flag_mask);
     _header._struct._flags = (new_state << trap_shift) | old_flags;
   }
   u1 flags() {
     return _header._struct._flags;
   }
   u2 bci() {
     return _header._struct._bci;
   }
   void set_header(intptr_t value) {
     _header._bits = value;
   }
   void release_set_header(intptr_t value) {
     OrderAccess::release_store_ptr(&_header._bits, value);
   }
   intptr_t header() {
     return _header._bits;
   }
   void set_cell_at(int index, intptr_t value) {
     _cells[index] = value;
   }
   void release_set_cell_at(int index, intptr_t value) {
     OrderAccess::release_store_ptr(&_cells[index], value);
   }
   intptr_t cell_at(int index) {
     return _cells[index];
   }
   intptr_t* adr_cell_at(int index) {
     return &_cells[index];
   }
   oop* adr_oop_at(int index) {
     return (oop*)&(_cells[index]);
   }
   void set_flag_at(int flag_number) {
     assert(flag_number < flag_limit, "oob");
     _header._struct._flags |= (0x1 << flag_number);
   }
   bool flag_at(int flag_number) {
     assert(flag_number < flag_limit, "oob");
     return (_header._struct._flags & (0x1 << flag_number)) != 0;
   }
   // Low-level support for code generation.
   static ByteSize header_offset() {
     return byte_offset_of(DataLayout, _header);
   }
   static ByteSize tag_offset() {
     return byte_offset_of(DataLayout, _header._struct._tag);
   }
   static ByteSize flags_offset() {
     return byte_offset_of(DataLayout, _header._struct._flags);
   }
   static ByteSize bci_offset() {
     return byte_offset_of(DataLayout, _header._struct._bci);
   }
   static ByteSize cell_offset(int index) {
     return byte_offset_of(DataLayout, _cells) + in_ByteSize(index * cell_size);
   }
   // Return a value which, when or-ed as a byte into _flags, sets the flag.
   static int flag_number_to_byte_constant(int flag_number) {
     assert(0 <= flag_number && flag_number < flag_limit, "oob");
     DataLayout temp; temp.set_header(0);
     temp.set_flag_at(flag_number);
     return temp._header._struct._flags;
   }
   // Return a value which, when or-ed as a word into _header, sets the flag.
   static intptr_t flag_mask_to_header_mask(int byte_constant) {
     DataLayout temp; temp.set_header(0);
     temp._header._struct._flags = byte_constant;
     return temp._header._bits;
   }
   // GC support
   ProfileData* data_in();
   void follow_weak_refs(BoolObjectClosure* cl);
 };
 // ProfileData class hierarchy
 class ProfileData;
 class   BitData;
 class     CounterData;
 class       ReceiverTypeData;
 class         VirtualCallData;
 class       RetData;
 class   JumpData;
 class     BranchData;
 class   ArrayData;
 class     MultiBranchData;
 class     ArgInfoData;
 // ProfileData
 //
 // A ProfileData object is created to refer to a section of profiling
 // data in a structured way.
 class ProfileData : public ResourceObj {
 private:
 #ifndef PRODUCT
   enum {
     tab_width_one = 16,
     tab_width_two = 36
   };
 #endif // !PRODUCT
   // This is a pointer to a section of profiling data.
   DataLayout* _data;
 protected:
   DataLayout* data() { return _data; }
   enum {
     cell_size = DataLayout::cell_size
   };
 public:
   // How many cells are in this?
   virtual int cell_count() {
     ShouldNotReachHere();
     return -1;
   }
   // Return the size of this data.
   int size_in_bytes() {
     return DataLayout::compute_size_in_bytes(cell_count());
   }
 protected:
   // Low-level accessors for underlying data
   void set_intptr_at(int index, intptr_t value) {
     assert(0 <= index && index < cell_count(), "oob");
     data()->set_cell_at(index, value);
   }
   void release_set_intptr_at(int index, intptr_t value) {
     assert(0 <= index && index < cell_count(), "oob");
     data()->release_set_cell_at(index, value);
   }
   intptr_t intptr_at(int index) {
     assert(0 <= index && index < cell_count(), "oob");
     return data()->cell_at(index);
   }
   void set_uint_at(int index, uint value) {
     set_intptr_at(index, (intptr_t) value);
   }
   void release_set_uint_at(int index, uint value) {
     release_set_intptr_at(index, (intptr_t) value);
   }
   uint uint_at(int index) {
     return (uint)intptr_at(index);
   }
   void set_int_at(int index, int value) {
     set_intptr_at(index, (intptr_t) value);
   }
   void release_set_int_at(int index, int value) {
     release_set_intptr_at(index, (intptr_t) value);
   }
   int int_at(int index) {
     return (int)intptr_at(index);
   }
   int int_at_unchecked(int index) {
     return (int)data()->cell_at(index);
   }
   void set_oop_at(int index, oop value) {
     set_intptr_at(index, (intptr_t) value);
   }
   oop oop_at(int index) {
     return (oop)intptr_at(index);
   }
   oop* adr_oop_at(int index) {
     assert(0 <= index && index < cell_count(), "oob");
     return data()->adr_oop_at(index);
   }
   void set_flag_at(int flag_number) {
     data()->set_flag_at(flag_number);
   }
   bool flag_at(int flag_number) {
     return data()->flag_at(flag_number);
   }
   // two convenient imports for use by subclasses:
   static ByteSize cell_offset(int index) {
     return DataLayout::cell_offset(index);
   }
   static int flag_number_to_byte_constant(int flag_number) {
     return DataLayout::flag_number_to_byte_constant(flag_number);
   }
   ProfileData(DataLayout* data) {
     _data = data;
   }
 public:
   // Constructor for invalid ProfileData.
   ProfileData();
   u2 bci() {
     return data()->bci();
   }
   address dp() {
     return (address)_data;
   }
   int trap_state() {
     return data()->trap_state();
   }
   void set_trap_state(int new_state) {
     data()->set_trap_state(new_state);
   }
   // Type checking
   virtual bool is_BitData()         { return false; }
   virtual bool is_CounterData()     { return false; }
   virtual bool is_JumpData()        { return false; }
   virtual bool is_ReceiverTypeData(){ return false; }
   virtual bool is_VirtualCallData() { return false; }
   virtual bool is_RetData()         { return false; }
   virtual bool is_BranchData()      { return false; }
   virtual bool is_ArrayData()       { return false; }
   virtual bool is_MultiBranchData() { return false; }
   virtual bool is_ArgInfoData()     { return false; }
   BitData* as_BitData() {
     assert(is_BitData(), "wrong type");
     return is_BitData()         ? (BitData*)        this : NULL;
   }
   CounterData* as_CounterData() {
     assert(is_CounterData(), "wrong type");
     return is_CounterData()     ? (CounterData*)    this : NULL;
   }
   JumpData* as_JumpData() {
     assert(is_JumpData(), "wrong type");
     return is_JumpData()        ? (JumpData*)       this : NULL;
   }
   ReceiverTypeData* as_ReceiverTypeData() {
     assert(is_ReceiverTypeData(), "wrong type");
     return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
   }
   VirtualCallData* as_VirtualCallData() {
     assert(is_VirtualCallData(), "wrong type");
     return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
   }
   RetData* as_RetData() {
     assert(is_RetData(), "wrong type");
     return is_RetData()         ? (RetData*)        this : NULL;
   }
   BranchData* as_BranchData() {
     assert(is_BranchData(), "wrong type");
     return is_BranchData()      ? (BranchData*)     this : NULL;
   }
   ArrayData* as_ArrayData() {
     assert(is_ArrayData(), "wrong type");
     return is_ArrayData()       ? (ArrayData*)      this : NULL;
   }
   MultiBranchData* as_MultiBranchData() {
     assert(is_MultiBranchData(), "wrong type");
     return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
   }
   ArgInfoData* as_ArgInfoData() {
     assert(is_ArgInfoData(), "wrong type");
     return is_ArgInfoData() ? (ArgInfoData*)this : NULL;
   }
   // Subclass specific initialization
   virtual void post_initialize(BytecodeStream* stream, methodDataOop mdo) {}
   // GC support
   virtual void follow_contents() {}
   virtual void oop_iterate(OopClosure* blk) {}
   virtual void oop_iterate_m(OopClosure* blk, MemRegion mr) {}
   virtual void adjust_pointers() {}
   virtual void follow_weak_refs(BoolObjectClosure* is_alive_closure) {}
 #ifndef SERIALGC
   // Parallel old support
   virtual void follow_contents(ParCompactionManager* cm) {}
   virtual void update_pointers() {}
 #endif // SERIALGC
   // CI translation: ProfileData can represent both MethodDataOop data
   // as well as CIMethodData data. This function is provided for translating
   // an oop in a ProfileData to the ci equivalent. Generally speaking,
   // most ProfileData don't require any translation, so we provide the null
   // translation here, and the required translators are in the ci subclasses.
   virtual void translate_from(ProfileData* data) {}
   virtual void print_data_on(outputStream* st) {
     ShouldNotReachHere();
   }
 #ifndef PRODUCT
   void print_shared(outputStream* st, const char* name);
   void tab(outputStream* st);
 #endif
 };
 // BitData
 //
 // A BitData holds a flag or two in its header.
 class BitData : public ProfileData {
 protected:
   enum {
     // null_seen:
     //  saw a null operand (cast/aastore/instanceof)
     null_seen_flag              = DataLayout::first_flag + 0
   };
   enum { bit_cell_count = 0 };  // no additional data fields needed.
 public:
   BitData(DataLayout* layout) : ProfileData(layout) {
   }
   virtual bool is_BitData() { return true; }
   static int static_cell_count() {
     return bit_cell_count;
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   // Accessor
   // The null_seen flag bit is specially known to the interpreter.
   // Consulting it allows the compiler to avoid setting up null_check traps.
   bool null_seen()     { return flag_at(null_seen_flag); }
   void set_null_seen()    { set_flag_at(null_seen_flag); }
   // Code generation support
   static int null_seen_byte_constant() {
     return flag_number_to_byte_constant(null_seen_flag);
   }
   static ByteSize bit_data_size() {
     return cell_offset(bit_cell_count);
   }
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // CounterData
 //
 // A CounterData corresponds to a simple counter.
 class CounterData : public BitData {
 protected:
   enum {
     count_off,
     counter_cell_count
   };
 public:
   CounterData(DataLayout* layout) : BitData(layout) {}
   virtual bool is_CounterData() { return true; }
   static int static_cell_count() {
     return counter_cell_count;
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   // Direct accessor
   uint count() {
     return uint_at(count_off);
   }
   // Code generation support
   static ByteSize count_offset() {
     return cell_offset(count_off);
   }
   static ByteSize counter_data_size() {
     return cell_offset(counter_cell_count);
   }
   void set_count(uint count) {
     set_uint_at(count_off, count);
   }
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // JumpData
 //
 // A JumpData is used to access profiling information for a direct
 // branch.  It is a counter, used for counting the number of branches,
 // plus a data displacement, used for realigning the data pointer to
 // the corresponding target bci.
 class JumpData : public ProfileData {
 protected:
   enum {
     taken_off_set,
     displacement_off_set,
     jump_cell_count
   };
   void set_displacement(int displacement) {
     set_int_at(displacement_off_set, displacement);
   }
 public:
   JumpData(DataLayout* layout) : ProfileData(layout) {
     assert(layout->tag() == DataLayout::jump_data_tag ||
       layout->tag() == DataLayout::branch_data_tag, "wrong type");
   }
   virtual bool is_JumpData() { return true; }
   static int static_cell_count() {
     return jump_cell_count;
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   // Direct accessor
   uint taken() {
     return uint_at(taken_off_set);
   }
   // Saturating counter
   uint inc_taken() {
     uint cnt = taken() + 1;
     // Did we wrap? Will compiler screw us??
     if (cnt == 0) cnt--;
     set_uint_at(taken_off_set, cnt);
     return cnt;
   }
   int displacement() {
     return int_at(displacement_off_set);
   }
   // Code generation support
   static ByteSize taken_offset() {
     return cell_offset(taken_off_set);
   }
   static ByteSize displacement_offset() {
     return cell_offset(displacement_off_set);
   }
   // Specific initialization.
   void post_initialize(BytecodeStream* stream, methodDataOop mdo);
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // ReceiverTypeData
 //
 // A ReceiverTypeData is used to access profiling information about a
 // dynamic type check.  It consists of a counter which counts the total times
 // that the check is reached, and a series of (klassOop, count) pairs
 // which are used to store a type profile for the receiver of the check.
 class ReceiverTypeData : public CounterData {
 protected:
   enum {
     receiver0_offset = counter_cell_count,
     count0_offset,
     receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
   };
 public:
   ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
     assert(layout->tag() == DataLayout::receiver_type_data_tag ||
            layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
   }
   virtual bool is_ReceiverTypeData() { return true; }
   static int static_cell_count() {
     return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count;
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   // Direct accessors
   static uint row_limit() {
     return TypeProfileWidth;
   }
   static int receiver_cell_index(uint row) {
     return receiver0_offset + row * receiver_type_row_cell_count;
   }
   static int receiver_count_cell_index(uint row) {
     return count0_offset + row * receiver_type_row_cell_count;
   }
   // Get the receiver at row.  The 'unchecked' version is needed by parallel old
   // gc; it does not assert the receiver is a klass.  During compaction of the
   // perm gen, the klass may already have moved, so the is_klass() predicate
   // would fail.  The 'normal' version should be used whenever possible.
   klassOop receiver_unchecked(uint row) {
     assert(row < row_limit(), "oob");
     oop recv = oop_at(receiver_cell_index(row));
     return (klassOop)recv;
   }
   klassOop receiver(uint row) {
     klassOop recv = receiver_unchecked(row);
     assert(recv == NULL || ((oop)recv)->is_klass(), "wrong type");
     return recv;
   }
   void set_receiver(uint row, oop p) {
     assert((uint)row < row_limit(), "oob");
     set_oop_at(receiver_cell_index(row), p);
   }
   uint receiver_count(uint row) {
     assert(row < row_limit(), "oob");
     return uint_at(receiver_count_cell_index(row));
   }
   void set_receiver_count(uint row, uint count) {
     assert(row < row_limit(), "oob");
     set_uint_at(receiver_count_cell_index(row), count);
   }
   void clear_row(uint row) {
     assert(row < row_limit(), "oob");
     // Clear total count - indicator of polymorphic call site.
     // The site may look like as monomorphic after that but
     // it allow to have more accurate profiling information because
     // there was execution phase change since klasses were unloaded.
     // If the site is still polymorphic then MDO will be updated
     // to reflect it. But it could be the case that the site becomes
     // only bimorphic. Then keeping total count not 0 will be wrong.
     // Even if we use monomorphic (when it is not) for compilation
     // we will only have trap, deoptimization and recompile again
     // with updated MDO after executing method in Interpreter.
     // An additional receiver will be recorded in the cleaned row
     // during next call execution.
     //
     // Note: our profiling logic works with empty rows in any slot.
     // We do sorting a profiling info (ciCallProfile) for compilation.
     //
     set_count(0);
     set_receiver(row, NULL);
     set_receiver_count(row, 0);
   }
   // Code generation support
   static ByteSize receiver_offset(uint row) {
     return cell_offset(receiver_cell_index(row));
   }
   static ByteSize receiver_count_offset(uint row) {
     return cell_offset(receiver_count_cell_index(row));
   }
   static ByteSize receiver_type_data_size() {
     return cell_offset(static_cell_count());
   }
   // GC support
   virtual void follow_contents();
   virtual void oop_iterate(OopClosure* blk);
   virtual void oop_iterate_m(OopClosure* blk, MemRegion mr);
   virtual void adjust_pointers();
   virtual void follow_weak_refs(BoolObjectClosure* is_alive_closure);
 #ifndef SERIALGC
   // Parallel old support
   virtual void follow_contents(ParCompactionManager* cm);
   virtual void update_pointers();
 #endif // SERIALGC
   oop* adr_receiver(uint row) {
     return adr_oop_at(receiver_cell_index(row));
   }
 #ifndef PRODUCT
   void print_receiver_data_on(outputStream* st);
   void print_data_on(outputStream* st);
 #endif
 };
 // VirtualCallData
 //
 // A VirtualCallData is used to access profiling information about a
 // virtual call.  For now, it has nothing more than a ReceiverTypeData.
 class VirtualCallData : public ReceiverTypeData {
 public:
   VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
     assert(layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
   }
   virtual bool is_VirtualCallData() { return true; }
   static int static_cell_count() {
     // At this point we could add more profile state, e.g., for arguments.
     // But for now it's the same size as the base record type.
     return ReceiverTypeData::static_cell_count();
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   // Direct accessors
   static ByteSize virtual_call_data_size() {
     return cell_offset(static_cell_count());
   }
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // RetData
 //
 // A RetData is used to access profiling information for a ret bytecode.
 // It is composed of a count of the number of times that the ret has
 // been executed, followed by a series of triples of the form
 // (bci, count, di) which count the number of times that some bci was the
 // target of the ret and cache a corresponding data displacement.
 class RetData : public CounterData {
 protected:
   enum {
     bci0_offset = counter_cell_count,
     count0_offset,
     displacement0_offset,
     ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
   };
   void set_bci(uint row, int bci) {
     assert((uint)row < row_limit(), "oob");
     set_int_at(bci0_offset + row * ret_row_cell_count, bci);
   }
   void release_set_bci(uint row, int bci) {
     assert((uint)row < row_limit(), "oob");
     // 'release' when setting the bci acts as a valid flag for other
     // threads wrt bci_count and bci_displacement.
     release_set_int_at(bci0_offset + row * ret_row_cell_count, bci);
   }
   void set_bci_count(uint row, uint count) {
     assert((uint)row < row_limit(), "oob");
     set_uint_at(count0_offset + row * ret_row_cell_count, count);
   }
   void set_bci_displacement(uint row, int disp) {
     set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
   }
 public:
   RetData(DataLayout* layout) : CounterData(layout) {
     assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
   }
   virtual bool is_RetData() { return true; }
   enum {
     no_bci = -1 // value of bci when bci1/2 are not in use.
   };
   static int static_cell_count() {
     return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   static uint row_limit() {
     return BciProfileWidth;
   }
   static int bci_cell_index(uint row) {
     return bci0_offset + row * ret_row_cell_count;
   }
   static int bci_count_cell_index(uint row) {
     return count0_offset + row * ret_row_cell_count;
   }
   static int bci_displacement_cell_index(uint row) {
     return displacement0_offset + row * ret_row_cell_count;
   }
   // Direct accessors
   int bci(uint row) {
     return int_at(bci_cell_index(row));
   }
   uint bci_count(uint row) {
     return uint_at(bci_count_cell_index(row));
   }
   int bci_displacement(uint row) {
     return int_at(bci_displacement_cell_index(row));
   }
   // Interpreter Runtime support
   address fixup_ret(int return_bci, methodDataHandle mdo);
   // Code generation support
   static ByteSize bci_offset(uint row) {
     return cell_offset(bci_cell_index(row));
   }
   static ByteSize bci_count_offset(uint row) {
     return cell_offset(bci_count_cell_index(row));
   }
   static ByteSize bci_displacement_offset(uint row) {
     return cell_offset(bci_displacement_cell_index(row));
   }
   // Specific initialization.
   void post_initialize(BytecodeStream* stream, methodDataOop mdo);
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // BranchData
 //
 // A BranchData is used to access profiling data for a two-way branch.
 // It consists of taken and not_taken counts as well as a data displacement
 // for the taken case.
 class BranchData : public JumpData {
 protected:
   enum {
     not_taken_off_set = jump_cell_count,
     branch_cell_count
   };
   void set_displacement(int displacement) {
     set_int_at(displacement_off_set, displacement);
   }
 public:
   BranchData(DataLayout* layout) : JumpData(layout) {
     assert(layout->tag() == DataLayout::branch_data_tag, "wrong type");
   }
   virtual bool is_BranchData() { return true; }
   static int static_cell_count() {
     return branch_cell_count;
   }
   virtual int cell_count() {
     return static_cell_count();
   }
   // Direct accessor
   uint not_taken() {
     return uint_at(not_taken_off_set);
   }
   uint inc_not_taken() {
     uint cnt = not_taken() + 1;
     // Did we wrap? Will compiler screw us??
     if (cnt == 0) cnt--;
     set_uint_at(not_taken_off_set, cnt);
     return cnt;
   }
   // Code generation support
   static ByteSize not_taken_offset() {
     return cell_offset(not_taken_off_set);
   }
   static ByteSize branch_data_size() {
     return cell_offset(branch_cell_count);
   }
   // Specific initialization.
   void post_initialize(BytecodeStream* stream, methodDataOop mdo);
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // ArrayData
 //
 // A ArrayData is a base class for accessing profiling data which does
 // not have a statically known size.  It consists of an array length
 // and an array start.
 class ArrayData : public ProfileData {
 protected:
   friend class DataLayout;
   enum {
     array_len_off_set,
     array_start_off_set
   };
   uint array_uint_at(int index) {
     int aindex = index + array_start_off_set;
     return uint_at(aindex);
   }
   int array_int_at(int index) {
     int aindex = index + array_start_off_set;
     return int_at(aindex);
   }
   oop array_oop_at(int index) {
     int aindex = index + array_start_off_set;
     return oop_at(aindex);
   }
   void array_set_int_at(int index, int value) {
     int aindex = index + array_start_off_set;
     set_int_at(aindex, value);
   }
   // Code generation support for subclasses.
   static ByteSize array_element_offset(int index) {
     return cell_offset(array_start_off_set + index);
   }
 public:
   ArrayData(DataLayout* layout) : ProfileData(layout) {}
   virtual bool is_ArrayData() { return true; }
   static int static_cell_count() {
     return -1;
   }
   int array_len() {
     return int_at_unchecked(array_len_off_set);
   }
   virtual int cell_count() {
     return array_len() + 1;
   }
   // Code generation support
   static ByteSize array_len_offset() {
     return cell_offset(array_len_off_set);
   }
   static ByteSize array_start_offset() {
     return cell_offset(array_start_off_set);
   }
 };
 // MultiBranchData
 //
 // A MultiBranchData is used to access profiling information for
 // a multi-way branch (*switch bytecodes).  It consists of a series
 // of (count, displacement) pairs, which count the number of times each
 // case was taken and specify the data displacment for each branch target.
 class MultiBranchData : public ArrayData {
 protected:
   enum {
     default_count_off_set,
     default_disaplacement_off_set,
     case_array_start
   };
   enum {
     relative_count_off_set,
     relative_displacement_off_set,
     per_case_cell_count
   };
   void set_default_displacement(int displacement) {
     array_set_int_at(default_disaplacement_off_set, displacement);
   }
   void set_displacement_at(int index, int displacement) {
     array_set_int_at(case_array_start +
                      index * per_case_cell_count +
                      relative_displacement_off_set,
                      displacement);
   }
 public:
   MultiBranchData(DataLayout* layout) : ArrayData(layout) {
     assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
   }
   virtual bool is_MultiBranchData() { return true; }
   static int compute_cell_count(BytecodeStream* stream);
   int number_of_cases() {
     int alen = array_len() - 2; // get rid of default case here.
     assert(alen % per_case_cell_count == 0, "must be even");
     return (alen / per_case_cell_count);
   }
   uint default_count() {
     return array_uint_at(default_count_off_set);
   }
   int default_displacement() {
     return array_int_at(default_disaplacement_off_set);
   }
   uint count_at(int index) {
     return array_uint_at(case_array_start +
                          index * per_case_cell_count +
                          relative_count_off_set);
   }
   int displacement_at(int index) {
     return array_int_at(case_array_start +
                         index * per_case_cell_count +
                         relative_displacement_off_set);
   }
   // Code generation support
   static ByteSize default_count_offset() {
     return array_element_offset(default_count_off_set);
   }
   static ByteSize default_displacement_offset() {
     return array_element_offset(default_disaplacement_off_set);
   }
   static ByteSize case_count_offset(int index) {
     return case_array_offset() +
            (per_case_size() * index) +
            relative_count_offset();
   }
   static ByteSize case_array_offset() {
     return array_element_offset(case_array_start);
   }
   static ByteSize per_case_size() {
     return in_ByteSize(per_case_cell_count) * cell_size;
   }
   static ByteSize relative_count_offset() {
     return in_ByteSize(relative_count_off_set) * cell_size;
   }
   static ByteSize relative_displacement_offset() {
     return in_ByteSize(relative_displacement_off_set) * cell_size;
   }
   // Specific initialization.
   void post_initialize(BytecodeStream* stream, methodDataOop mdo);
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 class ArgInfoData : public ArrayData {
 public:
   ArgInfoData(DataLayout* layout) : ArrayData(layout) {
     assert(layout->tag() == DataLayout::arg_info_data_tag, "wrong type");
   }
   virtual bool is_ArgInfoData() { return true; }
   int number_of_args() {
     return array_len();
   }
   uint arg_modified(int arg) {
     return array_uint_at(arg);
   }
   void set_arg_modified(int arg, uint val) {
     array_set_int_at(arg, val);
   }
 #ifndef PRODUCT
   void print_data_on(outputStream* st);
 #endif
 };
 // methodDataOop
 //
 // A methodDataOop holds information which has been collected about
 // a method.  Its layout looks like this:
 //
 // -----------------------------
 // | header                    |
 // | klass                     |
 // -----------------------------
 // | method                    |
 // | size of the methodDataOop |
 // -----------------------------
 // | Data entries...           |
 // |   (variable size)         |
 // |                           |
 // .                           .
 // .                           .
 // .                           .
 // |                           |
 // -----------------------------
 //
 // The data entry area is a heterogeneous array of DataLayouts. Each
 // DataLayout in the array corresponds to a specific bytecode in the
 // method.  The entries in the array are sorted by the corresponding
 // bytecode.  Access to the data is via resource-allocated ProfileData,
 // which point to the underlying blocks of DataLayout structures.
 //
 // During interpretation, if profiling in enabled, the interpreter
 // maintains a method data pointer (mdp), which points at the entry
 // in the array corresponding to the current bci.  In the course of
 // intepretation, when a bytecode is encountered that has profile data
 // associated with it, the entry pointed to by mdp is updated, then the
 // mdp is adjusted to point to the next appropriate DataLayout.  If mdp
 // is NULL to begin with, the interpreter assumes that the current method
 // is not (yet) being profiled.
 //
 // In methodDataOop parlance, "dp" is a "data pointer", the actual address
 // of a DataLayout element.  A "di" is a "data index", the offset in bytes
 // from the base of the data entry array.  A "displacement" is the byte offset
 // in certain ProfileData objects that indicate the amount the mdp must be
 // adjusted in the event of a change in control flow.
 //
 class methodDataOopDesc : public oopDesc {
   friend class VMStructs;
 private:
   friend class ProfileData;
   // Back pointer to the methodOop
   methodOop _method;
   // Size of this oop in bytes
   int _size;
   // Cached hint for bci_to_dp and bci_to_data
   int _hint_di;
   // Whole-method sticky bits and flags
 public:
   enum {
     _trap_hist_limit    = 16,   // decoupled from Deoptimization::Reason_LIMIT
     _trap_hist_mask     = max_jubyte,
     _extra_data_count   = 4     // extra DataLayout headers, for trap history
   }; // Public flag values
 private:
   uint _nof_decompiles;             // count of all nmethod removals
   uint _nof_overflow_recompiles;    // recompile count, excluding recomp. bits
   uint _nof_overflow_traps;         // trap count, excluding _trap_hist
   union {
     intptr_t _align;
     u1 _array[_trap_hist_limit];
   } _trap_hist;
   // Support for interprocedural escape analysis, from Thomas Kotzmann.
   intx              _eflags;          // flags on escape information
   intx              _arg_local;       // bit set of non-escaping arguments
   intx              _arg_stack;       // bit set of stack-allocatable arguments
   intx              _arg_returned;    // bit set of returned arguments
   int _creation_mileage;              // method mileage at MDO creation
   // How many invocations has this MDO seen?
   // These counters are used to determine the exact age of MDO.
   // We need those because in tiered a method can be concurrently
   // executed at different levels.
   InvocationCounter _invocation_counter;
   // Same for backedges.
   InvocationCounter _backedge_counter;
   // Counter values at the time profiling started.
   int               _invocation_counter_start;
   int               _backedge_counter_start;
   // Number of loops and blocks is computed when compiling the first
   // time with C1. It is used to determine if method is trivial.
   short             _num_loops;
   short             _num_blocks;
   // Highest compile level this method has ever seen.
   u1                _highest_comp_level;
   // Same for OSR level
   u1                _highest_osr_comp_level;
   // Does this method contain anything worth profiling?
   bool              _would_profile;
   // Size of _data array in bytes.  (Excludes header and extra_data fields.)
   int _data_size;
   // Beginning of the data entries
   intptr_t _data[1];
   // Helper for size computation
   static int compute_data_size(BytecodeStream* stream);
   static int bytecode_cell_count(Bytecodes::Code code);
   enum { no_profile_data = -1, variable_cell_count = -2 };
   // Helper for initialization
   DataLayout* data_layout_at(int data_index) {
     assert(data_index % sizeof(intptr_t) == 0, "unaligned");
     return (DataLayout*) (((address)_data) + data_index);
   }
   // Initialize an individual data segment.  Returns the size of
   // the segment in bytes.
   int initialize_data(BytecodeStream* stream, int data_index);
   // Helper for data_at
   DataLayout* limit_data_position() {
     return (DataLayout*)((address)data_base() + _data_size);
   }
   bool out_of_bounds(int data_index) {
     return data_index >= data_size();
   }
   // Give each of the data entries a chance to perform specific
   // data initialization.
   void post_initialize(BytecodeStream* stream);
   // hint accessors
   int      hint_di() const  { return _hint_di; }
   void set_hint_di(int di)  {
     assert(!out_of_bounds(di), "hint_di out of bounds");
     _hint_di = di;
   }
   ProfileData* data_before(int bci) {
     // avoid SEGV on this edge case
     if (data_size() == 0)
       return NULL;
     int hint = hint_di();
     if (data_layout_at(hint)->bci() <= bci)
       return data_at(hint);
     return first_data();
   }
   // What is the index of the first data entry?
   int first_di() { return 0; }
   // Find or create an extra ProfileData:
   ProfileData* bci_to_extra_data(int bci, bool create_if_missing);
   // return the argument info cell
   ArgInfoData *arg_info();
 public:
   static int header_size() {
     return sizeof(methodDataOopDesc)/wordSize;
   }
   // Compute the size of a methodDataOop before it is created.
   static int compute_allocation_size_in_bytes(methodHandle method);
   static int compute_allocation_size_in_words(methodHandle method);
   static int compute_extra_data_count(int data_size, int empty_bc_count);
   // Determine if a given bytecode can have profile information.
   static bool bytecode_has_profile(Bytecodes::Code code) {
     return bytecode_cell_count(code) != no_profile_data;
   }
   // Perform initialization of a new methodDataOop
   void initialize(methodHandle method);
   // My size
   int object_size_in_bytes() { return _size; }
   int object_size() {
     return align_object_size(align_size_up(_size, BytesPerWord)/BytesPerWord);
   }
   int      creation_mileage() const  { return _creation_mileage; }
   void set_creation_mileage(int x)   { _creation_mileage = x; }
   int invocation_count() {
     if (invocation_counter()->carry()) {
       return InvocationCounter::count_limit;
     }
     return invocation_counter()->count();
   }
   int backedge_count() {
     if (backedge_counter()->carry()) {
       return InvocationCounter::count_limit;
     }
     return backedge_counter()->count();
   }
   int invocation_count_start() {
     if (invocation_counter()->carry()) {
       return 0;
     }
     return _invocation_counter_start;
   }
   int backedge_count_start() {
     if (backedge_counter()->carry()) {
       return 0;
     }
     return _backedge_counter_start;
   }
   int invocation_count_delta() { return invocation_count() - invocation_count_start(); }
   int backedge_count_delta()   { return backedge_count()   - backedge_count_start();   }
   void reset_start_counters() {
     _invocation_counter_start = invocation_count();
     _backedge_counter_start = backedge_count();
   }
   InvocationCounter* invocation_counter()     { return &_invocation_counter; }
   InvocationCounter* backedge_counter()       { return &_backedge_counter;   }
   void set_would_profile(bool p)              { _would_profile = p;    }
   bool would_profile() const                  { return _would_profile; }
   int highest_comp_level()                    { return _highest_comp_level;      }
   void set_highest_comp_level(int level)      { _highest_comp_level = level;     }
   int highest_osr_comp_level()                { return _highest_osr_comp_level;  }
   void set_highest_osr_comp_level(int level)  { _highest_osr_comp_level = level; }
   int num_loops() const                       { return _num_loops;  }
   void set_num_loops(int n)                   { _num_loops = n;     }
   int num_blocks() const                      { return _num_blocks; }
   void set_num_blocks(int n)                  { _num_blocks = n;    }
   bool is_mature() const;  // consult mileage and ProfileMaturityPercentage
   static int mileage_of(methodOop m);
   // Support for interprocedural escape analysis, from Thomas Kotzmann.
   enum EscapeFlag {
     estimated    = 1 << 0,
     return_local = 1 << 1,
     return_allocated = 1 << 2,
     allocated_escapes = 1 << 3,
     unknown_modified = 1 << 4
   };
   intx eflags()                                  { return _eflags; }
   intx arg_local()                               { return _arg_local; }
   intx arg_stack()                               { return _arg_stack; }
   intx arg_returned()                            { return _arg_returned; }
   uint arg_modified(int a)                       { ArgInfoData *aid = arg_info();
                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
                                                    return aid->arg_modified(a); }
   void set_eflags(intx v)                        { _eflags = v; }
   void set_arg_local(intx v)                     { _arg_local = v; }
   void set_arg_stack(intx v)                     { _arg_stack = v; }
   void set_arg_returned(intx v)                  { _arg_returned = v; }
   void set_arg_modified(int a, uint v)           { ArgInfoData *aid = arg_info();
                                                    assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
                                                    aid->set_arg_modified(a, v); }
   void clear_escape_info()                       { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
   // Location and size of data area
   address data_base() const {
     return (address) _data;
   }
   int data_size() {
     return _data_size;
   }
   // Accessors
   methodOop method() { return _method; }
   // Get the data at an arbitrary (sort of) data index.
   ProfileData* data_at(int data_index);
   // Walk through the data in order.
   ProfileData* first_data() { return data_at(first_di()); }
   ProfileData* next_data(ProfileData* current);
   bool is_valid(ProfileData* current) { return current != NULL; }
   // Convert a dp (data pointer) to a di (data index).
   int dp_to_di(address dp) {
     return dp - ((address)_data);
   }
   address di_to_dp(int di) {
     return (address)data_layout_at(di);
   }
   // bci to di/dp conversion.
   address bci_to_dp(int bci);
   int bci_to_di(int bci) {
     return dp_to_di(bci_to_dp(bci));
   }
   // Get the data at an arbitrary bci, or NULL if there is none.
   ProfileData* bci_to_data(int bci);
   // Same, but try to create an extra_data record if one is needed:
   ProfileData* allocate_bci_to_data(int bci) {
     ProfileData* data = bci_to_data(bci);
     return (data != NULL) ? data : bci_to_extra_data(bci, true);
   }
   // Add a handful of extra data records, for trap tracking.
   DataLayout* extra_data_base() { return limit_data_position(); }
   DataLayout* extra_data_limit() { return (DataLayout*)((address)this + object_size_in_bytes()); }
   int extra_data_size() { return (address)extra_data_limit()
                                - (address)extra_data_base(); }
   static DataLayout* next_extra(DataLayout* dp) { return (DataLayout*)((address)dp + in_bytes(DataLayout::cell_offset(0))); }
   // Return (uint)-1 for overflow.
   uint trap_count(int reason) const {
     assert((uint)reason < _trap_hist_limit, "oob");
     return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
   }
   // For loops:
   static uint trap_reason_limit() { return _trap_hist_limit; }
   static uint trap_count_limit()  { return _trap_hist_mask; }
   uint inc_trap_count(int reason) {
     // Count another trap, anywhere in this method.
     assert(reason >= 0, "must be single trap");
     if ((uint)reason < _trap_hist_limit) {
       uint cnt1 = 1 + _trap_hist._array[reason];
       if ((cnt1 & _trap_hist_mask) != 0) {  // if no counter overflow...
         _trap_hist._array[reason] = cnt1;
         return cnt1;
       } else {
         return _trap_hist_mask + (++_nof_overflow_traps);
       }
     } else {
       // Could not represent the count in the histogram.
       return (++_nof_overflow_traps);
     }
   }
   uint overflow_trap_count() const {
     return _nof_overflow_traps;
   }
   uint overflow_recompile_count() const {
     return _nof_overflow_recompiles;
   }
   void inc_overflow_recompile_count() {
     _nof_overflow_recompiles += 1;
   }
   uint decompile_count() const {
     return _nof_decompiles;
   }
   void inc_decompile_count() {
     _nof_decompiles += 1;
     if (decompile_count() > (uint)PerMethodRecompilationCutoff) {
       method()->set_not_compilable(CompLevel_full_optimization);
     }
   }
   // Support for code generation
   static ByteSize data_offset() {
     return byte_offset_of(methodDataOopDesc, _data[0]);
   }
   static ByteSize invocation_counter_offset() {
     return byte_offset_of(methodDataOopDesc, _invocation_counter);
   }
   static ByteSize backedge_counter_offset() {
     return byte_offset_of(methodDataOopDesc, _backedge_counter);
   }
   // GC support
   oop* adr_method() const { return (oop*)&_method; }
   bool object_is_parsable() const { return _size != 0; }
   void set_object_is_parsable(int object_size_in_bytes) { _size = object_size_in_bytes; }
 #ifndef PRODUCT
   // printing support for method data
   void print_data_on(outputStream* st);
 #endif
   // verification
   void verify_data_on(outputStream* st);
 };
 #endif // SHARE_VM_OOPS_METHODDATAOOP_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/oops/methodDataOop.hpp@e1162778c1c8 (annotated)

src/share/vm/oops/methodDataOop.hpp