1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/oops/fieldInfo.hpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,257 @@
1.4 +/*
1.5 + * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#ifndef SHARE_VM_OOPS_FIELDINFO_HPP
1.29 +#define SHARE_VM_OOPS_FIELDINFO_HPP
1.30 +
1.31 +#include "oops/constantPool.hpp"
1.32 +#include "oops/typeArrayOop.hpp"
1.33 +#include "classfile/vmSymbols.hpp"
1.34 +
1.35 +// This class represents the field information contained in the fields
1.36 +// array of an InstanceKlass. Currently it's laid on top an array of
1.37 +// Java shorts but in the future it could simply be used as a real
1.38 +// array type. FieldInfo generally shouldn't be used directly.
1.39 +// Fields should be queried either through InstanceKlass or through
1.40 +// the various FieldStreams.
1.41 +class FieldInfo VALUE_OBJ_CLASS_SPEC {
1.42 + friend class fieldDescriptor;
1.43 + friend class JavaFieldStream;
1.44 + friend class ClassFileParser;
1.45 +
1.46 + public:
1.47 + // fields
1.48 + // Field info extracted from the class file and stored
1.49 + // as an array of 6 shorts.
1.50 +
1.51 +#define FIELDINFO_TAG_SIZE 2
1.52 +#define FIELDINFO_TAG_BLANK 0
1.53 +#define FIELDINFO_TAG_OFFSET 1
1.54 +#define FIELDINFO_TAG_TYPE_PLAIN 2
1.55 +#define FIELDINFO_TAG_TYPE_CONTENDED 3
1.56 +#define FIELDINFO_TAG_MASK 3
1.57 +
1.58 + // Packed field has the tag, and can be either of:
1.59 + // hi bits <--------------------------- lo bits
1.60 + // |---------high---------|---------low---------|
1.61 + // ..........................................00 - blank
1.62 + // [------------------offset----------------]01 - real field offset
1.63 + // ......................[-------type-------]10 - plain field with type
1.64 + // [--contention_group--][-------type-------]11 - contended field with type and contention group
1.65 + enum FieldOffset {
1.66 + access_flags_offset = 0,
1.67 + name_index_offset = 1,
1.68 + signature_index_offset = 2,
1.69 + initval_index_offset = 3,
1.70 + low_packed_offset = 4,
1.71 + high_packed_offset = 5,
1.72 + field_slots = 6
1.73 + };
1.74 +
1.75 + private:
1.76 + u2 _shorts[field_slots];
1.77 +
1.78 + void set_name_index(u2 val) { _shorts[name_index_offset] = val; }
1.79 + void set_signature_index(u2 val) { _shorts[signature_index_offset] = val; }
1.80 + void set_initval_index(u2 val) { _shorts[initval_index_offset] = val; }
1.81 +
1.82 + u2 name_index() const { return _shorts[name_index_offset]; }
1.83 + u2 signature_index() const { return _shorts[signature_index_offset]; }
1.84 + u2 initval_index() const { return _shorts[initval_index_offset]; }
1.85 +
1.86 + public:
1.87 + static FieldInfo* from_field_array(Array<u2>* fields, int index) {
1.88 + return ((FieldInfo*)fields->adr_at(index * field_slots));
1.89 + }
1.90 + static FieldInfo* from_field_array(u2* fields, int index) {
1.91 + return ((FieldInfo*)(fields + index * field_slots));
1.92 + }
1.93 +
1.94 + void initialize(u2 access_flags,
1.95 + u2 name_index,
1.96 + u2 signature_index,
1.97 + u2 initval_index) {
1.98 + _shorts[access_flags_offset] = access_flags;
1.99 + _shorts[name_index_offset] = name_index;
1.100 + _shorts[signature_index_offset] = signature_index;
1.101 + _shorts[initval_index_offset] = initval_index;
1.102 + _shorts[low_packed_offset] = 0;
1.103 + _shorts[high_packed_offset] = 0;
1.104 + }
1.105 +
1.106 + u2 access_flags() const { return _shorts[access_flags_offset]; }
1.107 + u4 offset() const {
1.108 + u2 lo = _shorts[low_packed_offset];
1.109 + switch(lo & FIELDINFO_TAG_MASK) {
1.110 + case FIELDINFO_TAG_OFFSET:
1.111 + return build_int_from_shorts(_shorts[low_packed_offset], _shorts[high_packed_offset]) >> FIELDINFO_TAG_SIZE;
1.112 +#ifndef PRODUCT
1.113 + case FIELDINFO_TAG_TYPE_PLAIN:
1.114 + fatal("Asking offset for the plain type field");
1.115 + case FIELDINFO_TAG_TYPE_CONTENDED:
1.116 + fatal("Asking offset for the contended type field");
1.117 + case FIELDINFO_TAG_BLANK:
1.118 + fatal("Asking offset for the blank field");
1.119 +#endif
1.120 + }
1.121 + ShouldNotReachHere();
1.122 + return 0;
1.123 + }
1.124 +
1.125 + bool is_contended() const {
1.126 + u2 lo = _shorts[low_packed_offset];
1.127 + switch(lo & FIELDINFO_TAG_MASK) {
1.128 + case FIELDINFO_TAG_TYPE_PLAIN:
1.129 + return false;
1.130 + case FIELDINFO_TAG_TYPE_CONTENDED:
1.131 + return true;
1.132 +#ifndef PRODUCT
1.133 + case FIELDINFO_TAG_OFFSET:
1.134 + fatal("Asking contended flag for the field with offset");
1.135 + case FIELDINFO_TAG_BLANK:
1.136 + fatal("Asking contended flag for the blank field");
1.137 +#endif
1.138 + }
1.139 + ShouldNotReachHere();
1.140 + return false;
1.141 + }
1.142 +
1.143 + u2 contended_group() const {
1.144 + u2 lo = _shorts[low_packed_offset];
1.145 + switch(lo & FIELDINFO_TAG_MASK) {
1.146 + case FIELDINFO_TAG_TYPE_PLAIN:
1.147 + return 0;
1.148 + case FIELDINFO_TAG_TYPE_CONTENDED:
1.149 + return _shorts[high_packed_offset];
1.150 +#ifndef PRODUCT
1.151 + case FIELDINFO_TAG_OFFSET:
1.152 + fatal("Asking the contended group for the field with offset");
1.153 + case FIELDINFO_TAG_BLANK:
1.154 + fatal("Asking the contended group for the blank field");
1.155 +#endif
1.156 + }
1.157 + ShouldNotReachHere();
1.158 + return 0;
1.159 + }
1.160 +
1.161 + u2 allocation_type() const {
1.162 + u2 lo = _shorts[low_packed_offset];
1.163 + switch(lo & FIELDINFO_TAG_MASK) {
1.164 + case FIELDINFO_TAG_TYPE_PLAIN:
1.165 + case FIELDINFO_TAG_TYPE_CONTENDED:
1.166 + return (lo >> FIELDINFO_TAG_SIZE);
1.167 +#ifndef PRODUCT
1.168 + case FIELDINFO_TAG_OFFSET:
1.169 + fatal("Asking the field type for field with offset");
1.170 + case FIELDINFO_TAG_BLANK:
1.171 + fatal("Asking the field type for the blank field");
1.172 +#endif
1.173 + }
1.174 + ShouldNotReachHere();
1.175 + return 0;
1.176 + }
1.177 +
1.178 + bool is_offset_set() const {
1.179 + return (_shorts[low_packed_offset] & FIELDINFO_TAG_MASK) == FIELDINFO_TAG_OFFSET;
1.180 + }
1.181 +
1.182 + Symbol* name(constantPoolHandle cp) const {
1.183 + int index = name_index();
1.184 + if (is_internal()) {
1.185 + return lookup_symbol(index);
1.186 + }
1.187 + return cp->symbol_at(index);
1.188 + }
1.189 +
1.190 + Symbol* signature(constantPoolHandle cp) const {
1.191 + int index = signature_index();
1.192 + if (is_internal()) {
1.193 + return lookup_symbol(index);
1.194 + }
1.195 + return cp->symbol_at(index);
1.196 + }
1.197 +
1.198 + void set_access_flags(u2 val) { _shorts[access_flags_offset] = val; }
1.199 + void set_offset(u4 val) {
1.200 + val = val << FIELDINFO_TAG_SIZE; // make room for tag
1.201 + _shorts[low_packed_offset] = extract_low_short_from_int(val) | FIELDINFO_TAG_OFFSET;
1.202 + _shorts[high_packed_offset] = extract_high_short_from_int(val);
1.203 + }
1.204 +
1.205 + void set_allocation_type(int type) {
1.206 + u2 lo = _shorts[low_packed_offset];
1.207 + switch(lo & FIELDINFO_TAG_MASK) {
1.208 + case FIELDINFO_TAG_BLANK:
1.209 + _shorts[low_packed_offset] = ((type << FIELDINFO_TAG_SIZE)) & 0xFFFF;
1.210 + _shorts[low_packed_offset] &= ~FIELDINFO_TAG_MASK;
1.211 + _shorts[low_packed_offset] |= FIELDINFO_TAG_TYPE_PLAIN;
1.212 + return;
1.213 +#ifndef PRODUCT
1.214 + case FIELDINFO_TAG_TYPE_PLAIN:
1.215 + case FIELDINFO_TAG_TYPE_CONTENDED:
1.216 + case FIELDINFO_TAG_OFFSET:
1.217 + fatal("Setting the field type with overwriting");
1.218 +#endif
1.219 + }
1.220 + ShouldNotReachHere();
1.221 + }
1.222 +
1.223 + void set_contended_group(u2 val) {
1.224 + u2 lo = _shorts[low_packed_offset];
1.225 + switch(lo & FIELDINFO_TAG_MASK) {
1.226 + case FIELDINFO_TAG_TYPE_PLAIN:
1.227 + _shorts[low_packed_offset] |= FIELDINFO_TAG_TYPE_CONTENDED;
1.228 + _shorts[high_packed_offset] = val;
1.229 + return;
1.230 +#ifndef PRODUCT
1.231 + case FIELDINFO_TAG_TYPE_CONTENDED:
1.232 + fatal("Overwriting contended group");
1.233 + case FIELDINFO_TAG_BLANK:
1.234 + fatal("Setting contended group for the blank field");
1.235 + case FIELDINFO_TAG_OFFSET:
1.236 + fatal("Setting contended group for field with offset");
1.237 +#endif
1.238 + }
1.239 + ShouldNotReachHere();
1.240 + }
1.241 +
1.242 + bool is_internal() const {
1.243 + return (access_flags() & JVM_ACC_FIELD_INTERNAL) != 0;
1.244 + }
1.245 +
1.246 + bool is_stable() const {
1.247 + return (access_flags() & JVM_ACC_FIELD_STABLE) != 0;
1.248 + }
1.249 + void set_stable(bool z) {
1.250 + if (z) _shorts[access_flags_offset] |= JVM_ACC_FIELD_STABLE;
1.251 + else _shorts[access_flags_offset] &= ~JVM_ACC_FIELD_STABLE;
1.252 + }
1.253 +
1.254 + Symbol* lookup_symbol(int symbol_index) const {
1.255 + assert(is_internal(), "only internal fields");
1.256 + return vmSymbols::symbol_at((vmSymbols::SID)symbol_index);
1.257 + }
1.258 +};
1.259 +
1.260 +#endif // SHARE_VM_OOPS_FIELDINFO_HPP
