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/*
! * Copyright (c) 2011, 2023, 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.
/*
! * Copyright (c) 2011, 2025, 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.
#ifndef SHARE_OOPS_FIELDINFO_HPP
#define SHARE_OOPS_FIELDINFO_HPP
#include "memory/allocation.hpp"
#include "oops/typeArrayOop.hpp"
#include "utilities/unsigned5.hpp"
#include "utilities/vmEnums.hpp"
static constexpr u4 flag_mask(int pos) {
return (u4)1 << pos;
}
-
// Helper class for access to the underlying Array<u1> used to
// store the compressed stream of FieldInfo
template<typename ARR, typename OFF>
struct ArrayHelper {
uint8_t operator()(ARR a, OFF i) const { return a->at(i); };
#ifndef SHARE_OOPS_FIELDINFO_HPP
#define SHARE_OOPS_FIELDINFO_HPP
#include "memory/allocation.hpp"
+ #include "oops/layoutKind.hpp"
#include "oops/typeArrayOop.hpp"
#include "utilities/unsigned5.hpp"
#include "utilities/vmEnums.hpp"
static constexpr u4 flag_mask(int pos) {
return (u4)1 << pos;
}
// Helper class for access to the underlying Array<u1> used to
// store the compressed stream of FieldInfo
template<typename ARR, typename OFF>
struct ArrayHelper {
uint8_t operator()(ARR a, OFF i) const { return a->at(i); };
public:
class FieldFlags {
friend class VMStructs;
friend class JVMCIVMStructs;
// The ordering of this enum is totally internal. More frequent
// flags should come earlier than less frequent ones, because
// earlier ones compress better.
enum FieldFlagBitPosition {
_ff_initialized, // has ConstantValue initializer attribute
_ff_injected, // internal field injected by the JVM
_ff_generic, // has a generic signature
_ff_stable, // trust as stable b/c declared as @Stable
! _ff_contended, // is contended, may have contention-group
};
// Some but not all of the flag bits signal the presence of an
// additional 32-bit item in the field record.
static const u4 _optional_item_bit_mask =
flag_mask((int)_ff_initialized) |
flag_mask((int)_ff_generic) |
! flag_mask((int)_ff_contended);
// boilerplate:
u4 _flags;
bool test_flag(FieldFlagBitPosition pos) const {
public:
class FieldFlags {
friend class VMStructs;
friend class JVMCIVMStructs;
+ friend class FieldDesc;
// The ordering of this enum is totally internal. More frequent
// flags should come earlier than less frequent ones, because
// earlier ones compress better.
enum FieldFlagBitPosition {
+ _ff_null_free_inline_type, // field's type is an inline type and the field is null free
+ _ff_flat, // field is a flat field, optional section includes a layout kind
+ _ff_null_marker, // field has a null marker, optional section includes the null marker offset
_ff_initialized, // has ConstantValue initializer attribute
_ff_injected, // internal field injected by the JVM
_ff_generic, // has a generic signature
_ff_stable, // trust as stable b/c declared as @Stable
! _ff_contended // is contended, may have contention-group
};
// Some but not all of the flag bits signal the presence of an
// additional 32-bit item in the field record.
static const u4 _optional_item_bit_mask =
flag_mask((int)_ff_initialized) |
flag_mask((int)_ff_generic) |
! flag_mask((int)_ff_contended) |
+ flag_mask((int)_ff_flat) |
+ flag_mask((int)_ff_null_marker);
// boilerplate:
u4 _flags;
bool test_flag(FieldFlagBitPosition pos) const {
bool has_any_optionals() const {
return (_flags & _optional_item_bit_mask) != 0;
}
bool is_initialized() const { return test_flag(_ff_initialized); }
+ bool is_null_free_inline_type() const { return test_flag(_ff_null_free_inline_type); }
+ bool is_flat() const { return test_flag(_ff_flat); }
bool is_injected() const { return test_flag(_ff_injected); }
bool is_generic() const { return test_flag(_ff_generic); }
bool is_stable() const { return test_flag(_ff_stable); }
bool is_contended() const { return test_flag(_ff_contended); }
+ bool has_null_marker() const { return test_flag(_ff_null_marker); }
void update_initialized(bool z) { update_flag(_ff_initialized, z); }
+ void update_null_free_inline_type(bool z) { update_flag(_ff_null_free_inline_type, z); }
+ void update_flat(bool z) { update_flag(_ff_flat, z); }
void update_injected(bool z) { update_flag(_ff_injected, z); }
void update_generic(bool z) { update_flag(_ff_generic, z); }
void update_stable(bool z) { update_flag(_ff_stable, z); }
void update_contended(bool z) { update_flag(_ff_contended, z); }
+ void update_null_marker(bool z) { update_flag(_ff_null_marker, z); }
};
private:
// The following items are the unpacked bitwise information content
// of a field record. Per-field metadata extracted from the class
u2 _name_index; // index in CP of name
u2 _signature_index; // index in CP of descriptor
u4 _offset; // offset in object layout
AccessFlags _access_flags; // access flags (JVM spec)
FieldFlags _field_flags; // VM defined flags (not JVM spec)
+ LayoutKind _layout_kind; // LayoutKind if the field is flat
+ u4 _null_marker_offset; // null marker offset for this field in the object layout
u2 _initializer_index; // index from ConstantValue attr (or 0)
u2 _generic_signature_index; // index from GenericSignature attr (or 0)
u2 _contention_group; // index from @Contended group item (or 0)
public:
FieldInfo() : _name_index(0),
_signature_index(0),
_offset(0),
_access_flags(AccessFlags(0)),
_field_flags(FieldFlags(0)),
+ _layout_kind(LayoutKind::UNKNOWN),
+ _null_marker_offset(0),
_initializer_index(0),
_generic_signature_index(0),
_contention_group(0) { }
FieldInfo(AccessFlags access_flags, u2 name_index, u2 signature_index, u2 initval_index, FieldInfo::FieldFlags fflags) :
_name_index(name_index),
_signature_index(signature_index),
_offset(0),
_access_flags(access_flags),
_field_flags(fflags),
+ _layout_kind(LayoutKind::UNKNOWN),
+ _null_marker_offset(0),
_initializer_index(initval_index),
_generic_signature_index(0),
_contention_group(0) {
if (initval_index != 0) {
_field_flags.update_initialized(true);
u4 offset() const { return _offset; }
void set_offset(u4 offset) { _offset = offset; }
AccessFlags access_flags() const { return _access_flags; }
FieldFlags field_flags() const { return _field_flags; }
FieldFlags* field_flags_addr() { return &_field_flags; }
+ LayoutKind layout_kind() const { return _layout_kind; }
+ void set_layout_kind(LayoutKind lk) {
+ assert(_field_flags.is_flat(), "Must be");
+ _layout_kind = lk;
+ }
+ u4 null_marker_offset() const { return _null_marker_offset; }
+ void set_null_marker_offset(u4 offset) {
+ _field_flags.update_null_marker(true);
+ _null_marker_offset = offset;
+ }
u2 initializer_index() const { return _initializer_index; }
void set_initializer_index(u2 index) { _initializer_index = index; }
u2 generic_signature_index() const { return _generic_signature_index; }
void set_generic_signature_index(u2 index) { _generic_signature_index = index; }
u2 contention_group() const { return _contention_group; }
class FieldStatus {
enum FieldStatusBitPosition {
_fs_access_watched, // field access is watched by JVMTI
_fs_modification_watched, // field modification is watched by JVMTI
+ _fs_strict_static_unset, // JVM_ACC_STRICT static field has not yet been set
+ _fs_strict_static_unread, // SS field has not yet been read
_initialized_final_update // (static) final field updated outside (class) initializer
};
// boilerplate:
u1 _flags;
public:
FieldStatus() { _flags = 0; }
FieldStatus(u1 flags) { _flags = flags; }
u1 as_uint() { return _flags; }
! bool is_access_watched() { return test_flag(_fs_access_watched); }
! bool is_modification_watched() { return test_flag(_fs_modification_watched); }
bool is_initialized_final_update() { return test_flag(_initialized_final_update); }
void update_access_watched(bool z);
void update_modification_watched(bool z);
void update_initialized_final_update(bool z);
};
#endif // SHARE_OOPS_FIELDINFO_HPP
public:
FieldStatus() { _flags = 0; }
FieldStatus(u1 flags) { _flags = flags; }
u1 as_uint() { return _flags; }
! bool is_access_watched() { return test_flag(_fs_access_watched); }
! bool is_modification_watched() { return test_flag(_fs_modification_watched); }
+ bool is_strict_static_unset() { return test_flag(_fs_strict_static_unset); }
+ bool is_strict_static_unread() { return test_flag(_fs_strict_static_unread); }
bool is_initialized_final_update() { return test_flag(_initialized_final_update); }
void update_access_watched(bool z);
void update_modification_watched(bool z);
+ void update_strict_static_unset(bool z);
+ void update_strict_static_unread(bool z);
void update_initialized_final_update(bool z);
};
#endif // SHARE_OOPS_FIELDINFO_HPP
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