never@3137: /*
mikael@6198:  * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
never@3137:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
never@3137:  *
never@3137:  * This code is free software; you can redistribute it and/or modify it
never@3137:  * under the terms of the GNU General Public License version 2 only, as
never@3137:  * published by the Free Software Foundation.
never@3137:  *
never@3137:  * This code is distributed in the hope that it will be useful, but WITHOUT
never@3137:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
never@3137:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
never@3137:  * version 2 for more details (a copy is included in the LICENSE file that
never@3137:  * accompanied this code).
never@3137:  *
never@3137:  * You should have received a copy of the GNU General Public License version
never@3137:  * 2 along with this work; if not, write to the Free Software Foundation,
never@3137:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
never@3137:  *
never@3137:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
never@3137:  * or visit www.oracle.com if you need additional information or have any
never@3137:  * questions.
never@3137:  *
never@3137:  */
never@3137: 
never@3137: #ifndef SHARE_VM_OOPS_FIELDINFO_HPP
never@3137: #define SHARE_VM_OOPS_FIELDINFO_HPP
never@3137: 
coleenp@4037: #include "oops/constantPool.hpp"
never@3137: #include "oops/typeArrayOop.hpp"
never@3137: #include "classfile/vmSymbols.hpp"
never@3137: 
never@3137: // This class represents the field information contained in the fields
coleenp@4037: // array of an InstanceKlass.  Currently it's laid on top an array of
never@3137: // Java shorts but in the future it could simply be used as a real
never@3137: // array type.  FieldInfo generally shouldn't be used directly.
coleenp@4037: // Fields should be queried either through InstanceKlass or through
never@3137: // the various FieldStreams.
never@3137: class FieldInfo VALUE_OBJ_CLASS_SPEC {
never@3137:   friend class fieldDescriptor;
never@3137:   friend class JavaFieldStream;
never@3137:   friend class ClassFileParser;
never@3137: 
never@3137:  public:
never@3137:   // fields
never@3137:   // Field info extracted from the class file and stored
jwilhelm@4430:   // as an array of 6 shorts.
jwilhelm@4430: 
jwilhelm@4430: #define FIELDINFO_TAG_SIZE             2
jwilhelm@4430: #define FIELDINFO_TAG_BLANK            0
jwilhelm@4430: #define FIELDINFO_TAG_OFFSET           1
jwilhelm@4430: #define FIELDINFO_TAG_TYPE_PLAIN       2
jwilhelm@4430: #define FIELDINFO_TAG_TYPE_CONTENDED   3
jwilhelm@4430: #define FIELDINFO_TAG_MASK             3
jwilhelm@4430: 
jwilhelm@4430:   // Packed field has the tag, and can be either of:
jwilhelm@4430:   //    hi bits <--------------------------- lo bits
jwilhelm@4430:   //   |---------high---------|---------low---------|
jwilhelm@4430:   //    ..........................................00  - blank
jwilhelm@4430:   //    [------------------offset----------------]01  - real field offset
jwilhelm@4430:   //    ......................[-------type-------]10  - plain field with type
jwilhelm@4430:   //    [--contention_group--][-------type-------]11  - contended field with type and contention group
never@3137:   enum FieldOffset {
never@3137:     access_flags_offset      = 0,
never@3137:     name_index_offset        = 1,
never@3137:     signature_index_offset   = 2,
never@3137:     initval_index_offset     = 3,
jwilhelm@4430:     low_packed_offset        = 4,
jwilhelm@4430:     high_packed_offset       = 5,
jiangli@3803:     field_slots              = 6
never@3137:   };
never@3137: 
never@3137:  private:
never@3137:   u2 _shorts[field_slots];
never@3137: 
never@3137:   void set_name_index(u2 val)                    { _shorts[name_index_offset] = val;         }
never@3137:   void set_signature_index(u2 val)               { _shorts[signature_index_offset] = val;    }
never@3137:   void set_initval_index(u2 val)                 { _shorts[initval_index_offset] = val;      }
never@3137: 
never@3137:   u2 name_index() const                          { return _shorts[name_index_offset];        }
never@3137:   u2 signature_index() const                     { return _shorts[signature_index_offset];   }
never@3137:   u2 initval_index() const                       { return _shorts[initval_index_offset];     }
never@3137: 
never@3137:  public:
coleenp@4037:   static FieldInfo* from_field_array(Array<u2>* fields, int index) {
coleenp@4037:     return ((FieldInfo*)fields->adr_at(index * field_slots));
never@3137:   }
jiangli@3803:   static FieldInfo* from_field_array(u2* fields, int index) {
jiangli@3803:     return ((FieldInfo*)(fields + index * field_slots));
jiangli@3803:   }
never@3137: 
never@3137:   void initialize(u2 access_flags,
never@3137:                   u2 name_index,
never@3137:                   u2 signature_index,
jwilhelm@4430:                   u2 initval_index) {
never@3137:     _shorts[access_flags_offset] = access_flags;
never@3137:     _shorts[name_index_offset] = name_index;
never@3137:     _shorts[signature_index_offset] = signature_index;
never@3137:     _shorts[initval_index_offset] = initval_index;
jwilhelm@4430:     _shorts[low_packed_offset] = 0;
jwilhelm@4430:     _shorts[high_packed_offset] = 0;
never@3137:   }
never@3137: 
never@3137:   u2 access_flags() const                        { return _shorts[access_flags_offset];            }
jwilhelm@4430:   u4 offset() const {
jwilhelm@4430:     u2 lo = _shorts[low_packed_offset];
jwilhelm@4430:     switch(lo & FIELDINFO_TAG_MASK) {
jwilhelm@4430:       case FIELDINFO_TAG_OFFSET:
jwilhelm@4430:         return build_int_from_shorts(_shorts[low_packed_offset], _shorts[high_packed_offset]) >> FIELDINFO_TAG_SIZE;
jwilhelm@4430: #ifndef PRODUCT
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_PLAIN:
neliasso@4769:         fatal("Asking offset for the plain type field");
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_CONTENDED:
neliasso@4769:         fatal("Asking offset for the contended type field");
jwilhelm@4430:       case FIELDINFO_TAG_BLANK:
neliasso@4769:         fatal("Asking offset for the blank field");
jwilhelm@4430: #endif
jwilhelm@4430:     }
jwilhelm@4430:     ShouldNotReachHere();
jwilhelm@4430:     return 0;
jwilhelm@4430:   }
jwilhelm@4430: 
jwilhelm@4430:   bool is_contended() const {
jwilhelm@4430:     u2 lo = _shorts[low_packed_offset];
jwilhelm@4430:     switch(lo & FIELDINFO_TAG_MASK) {
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_PLAIN:
jwilhelm@4430:         return false;
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_CONTENDED:
jwilhelm@4430:         return true;
jwilhelm@4430: #ifndef PRODUCT
jwilhelm@4430:       case FIELDINFO_TAG_OFFSET:
neliasso@4769:         fatal("Asking contended flag for the field with offset");
jwilhelm@4430:       case FIELDINFO_TAG_BLANK:
neliasso@4769:         fatal("Asking contended flag for the blank field");
jwilhelm@4430: #endif
jwilhelm@4430:     }
jwilhelm@4430:     ShouldNotReachHere();
jwilhelm@4430:     return false;
jwilhelm@4430:   }
jwilhelm@4430: 
jwilhelm@4430:   u2 contended_group() const {
jwilhelm@4430:     u2 lo = _shorts[low_packed_offset];
jwilhelm@4430:     switch(lo & FIELDINFO_TAG_MASK) {
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_PLAIN:
jwilhelm@4430:         return 0;
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_CONTENDED:
jwilhelm@4430:         return _shorts[high_packed_offset];
jwilhelm@4430: #ifndef PRODUCT
jwilhelm@4430:       case FIELDINFO_TAG_OFFSET:
neliasso@4769:         fatal("Asking the contended group for the field with offset");
jwilhelm@4430:       case FIELDINFO_TAG_BLANK:
neliasso@4769:         fatal("Asking the contended group for the blank field");
jwilhelm@4430: #endif
jwilhelm@4430:     }
jwilhelm@4430:     ShouldNotReachHere();
jwilhelm@4430:     return 0;
jwilhelm@4430:  }
jwilhelm@4430: 
jwilhelm@4430:   u2 allocation_type() const {
jwilhelm@4430:     u2 lo = _shorts[low_packed_offset];
jwilhelm@4430:     switch(lo & FIELDINFO_TAG_MASK) {
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_PLAIN:
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_CONTENDED:
jwilhelm@4430:         return (lo >> FIELDINFO_TAG_SIZE);
jwilhelm@4430: #ifndef PRODUCT
jwilhelm@4430:       case FIELDINFO_TAG_OFFSET:
neliasso@4769:         fatal("Asking the field type for field with offset");
jwilhelm@4430:       case FIELDINFO_TAG_BLANK:
neliasso@4769:         fatal("Asking the field type for the blank field");
jwilhelm@4430: #endif
jwilhelm@4430:     }
jwilhelm@4430:     ShouldNotReachHere();
jwilhelm@4430:     return 0;
jwilhelm@4430:   }
jwilhelm@4430: 
jwilhelm@4430:   bool is_offset_set() const {
jwilhelm@4430:     return (_shorts[low_packed_offset] & FIELDINFO_TAG_MASK) == FIELDINFO_TAG_OFFSET;
jwilhelm@4430:   }
never@3137: 
never@3137:   Symbol* name(constantPoolHandle cp) const {
never@3137:     int index = name_index();
never@3137:     if (is_internal()) {
never@3137:       return lookup_symbol(index);
never@3137:     }
never@3137:     return cp->symbol_at(index);
never@3137:   }
never@3137: 
never@3137:   Symbol* signature(constantPoolHandle cp) const {
never@3137:     int index = signature_index();
never@3137:     if (is_internal()) {
never@3137:       return lookup_symbol(index);
never@3137:     }
never@3137:     return cp->symbol_at(index);
never@3137:   }
never@3137: 
never@3137:   void set_access_flags(u2 val)                  { _shorts[access_flags_offset] = val;             }
never@3137:   void set_offset(u4 val)                        {
jwilhelm@4430:     val = val << FIELDINFO_TAG_SIZE; // make room for tag
jwilhelm@4430:     _shorts[low_packed_offset] = extract_low_short_from_int(val) | FIELDINFO_TAG_OFFSET;
jwilhelm@4430:     _shorts[high_packed_offset] = extract_high_short_from_int(val);
jwilhelm@4430:   }
jwilhelm@4430: 
jwilhelm@4430:   void set_allocation_type(int type) {
jwilhelm@4430:     u2 lo = _shorts[low_packed_offset];
jwilhelm@4430:     switch(lo & FIELDINFO_TAG_MASK) {
jwilhelm@4430:       case FIELDINFO_TAG_BLANK:
jwilhelm@4430:         _shorts[low_packed_offset] = ((type << FIELDINFO_TAG_SIZE)) & 0xFFFF;
jwilhelm@4430:         _shorts[low_packed_offset] &= ~FIELDINFO_TAG_MASK;
jwilhelm@4430:         _shorts[low_packed_offset] |= FIELDINFO_TAG_TYPE_PLAIN;
jwilhelm@4430:         return;
jwilhelm@4430: #ifndef PRODUCT
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_PLAIN:
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_CONTENDED:
jwilhelm@4430:       case FIELDINFO_TAG_OFFSET:
neliasso@4769:         fatal("Setting the field type with overwriting");
jwilhelm@4430: #endif
jwilhelm@4430:     }
jwilhelm@4430:     ShouldNotReachHere();
jwilhelm@4430:   }
jwilhelm@4430: 
jwilhelm@4430:   void set_contended_group(u2 val) {
jwilhelm@4430:     u2 lo = _shorts[low_packed_offset];
jwilhelm@4430:     switch(lo & FIELDINFO_TAG_MASK) {
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_PLAIN:
jwilhelm@4430:         _shorts[low_packed_offset] |= FIELDINFO_TAG_TYPE_CONTENDED;
jwilhelm@4430:         _shorts[high_packed_offset] = val;
jwilhelm@4430:         return;
jwilhelm@4430: #ifndef PRODUCT
jwilhelm@4430:       case FIELDINFO_TAG_TYPE_CONTENDED:
neliasso@4769:         fatal("Overwriting contended group");
jwilhelm@4430:       case FIELDINFO_TAG_BLANK:
neliasso@4769:         fatal("Setting contended group for the blank field");
jwilhelm@4430:       case FIELDINFO_TAG_OFFSET:
neliasso@4769:         fatal("Setting contended group for field with offset");
jwilhelm@4430: #endif
jwilhelm@4430:     }
jwilhelm@4430:     ShouldNotReachHere();
never@3137:   }
never@3137: 
never@3137:   bool is_internal() const {
never@3137:     return (access_flags() & JVM_ACC_FIELD_INTERNAL) != 0;
never@3137:   }
never@3137: 
vlivanov@5658:   bool is_stable() const {
vlivanov@5658:     return (access_flags() & JVM_ACC_FIELD_STABLE) != 0;
vlivanov@5658:   }
vlivanov@5658:   void set_stable(bool z) {
vlivanov@5658:     if (z) _shorts[access_flags_offset] |=  JVM_ACC_FIELD_STABLE;
vlivanov@5658:     else   _shorts[access_flags_offset] &= ~JVM_ACC_FIELD_STABLE;
vlivanov@5658:   }
vlivanov@5658: 
never@3137:   Symbol* lookup_symbol(int symbol_index) const {
never@3137:     assert(is_internal(), "only internal fields");
never@3137:     return vmSymbols::symbol_at((vmSymbols::SID)symbol_index);
never@3137:   }
never@3137: };
never@3137: 
never@3137: #endif // SHARE_VM_OOPS_FIELDINFO_HPP