src/share/vm/memory/modRefBarrierSet.hpp

Wed, 02 Jul 2008 12:55:16 -0700

author
xdono
date
Wed, 02 Jul 2008 12:55:16 -0700
changeset 631
d1605aabd0a1
parent 548
ba764ed4b6f2
child 791
1ee8caae33af
permissions
-rw-r--r--

6719955: Update copyright year
Summary: Update copyright year for files that have been modified in 2008
Reviewed-by: ohair, tbell

duke@435 1 /*
xdono@631 2 * Copyright 2000-2008 Sun Microsystems, Inc. All Rights Reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
duke@435 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435 20 * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435 21 * have any questions.
duke@435 22 *
duke@435 23 */
duke@435 24
duke@435 25 // This kind of "BarrierSet" allows a "CollectedHeap" to detect and
duke@435 26 // enumerate ref fields that have been modified (since the last
duke@435 27 // enumeration), using a card table.
duke@435 28
duke@435 29 class OopClosure;
duke@435 30 class Generation;
duke@435 31
duke@435 32 class ModRefBarrierSet: public BarrierSet {
duke@435 33 public:
duke@435 34 // Barriers only on ref writes.
duke@435 35 bool has_read_ref_barrier() { return false; }
duke@435 36 bool has_read_prim_barrier() { return false; }
duke@435 37 bool has_write_ref_barrier() { return true; }
duke@435 38 bool has_write_prim_barrier() { return false; }
duke@435 39
coleenp@548 40 bool read_ref_needs_barrier(void* field) { return false; }
duke@435 41 bool read_prim_needs_barrier(HeapWord* field, size_t bytes) { return false; }
coleenp@548 42 virtual bool write_ref_needs_barrier(void* field, oop new_val) = 0;
duke@435 43 bool write_prim_needs_barrier(HeapWord* field, size_t bytes,
duke@435 44 juint val1, juint val2) { return false; }
duke@435 45
duke@435 46 void write_prim_field(oop obj, size_t offset, size_t bytes,
duke@435 47 juint val1, juint val2) {}
duke@435 48
coleenp@548 49 void read_ref_field(void* field) {}
duke@435 50 void read_prim_field(HeapWord* field, size_t bytes) {}
duke@435 51 protected:
coleenp@548 52 virtual void write_ref_field_work(void* field, oop new_val) = 0;
duke@435 53 public:
duke@435 54 void write_prim_field(HeapWord* field, size_t bytes,
duke@435 55 juint val1, juint val2) {}
duke@435 56
duke@435 57 bool has_read_ref_array_opt() { return false; }
duke@435 58 bool has_read_prim_array_opt() { return false; }
duke@435 59 bool has_write_prim_array_opt() { return false; }
duke@435 60
duke@435 61 bool has_read_region_opt() { return false; }
duke@435 62
duke@435 63
duke@435 64 // These operations should assert false unless the correponding operation
duke@435 65 // above returns true.
duke@435 66 void read_ref_array(MemRegion mr) {
duke@435 67 assert(false, "can't call");
duke@435 68 }
duke@435 69 void read_prim_array(MemRegion mr) {
duke@435 70 assert(false, "can't call");
duke@435 71 }
duke@435 72 void write_prim_array(MemRegion mr) {
duke@435 73 assert(false, "can't call");
duke@435 74 }
duke@435 75 void read_region(MemRegion mr) {
duke@435 76 assert(false, "can't call");
duke@435 77 }
duke@435 78
duke@435 79 // Invoke "cl->do_oop" on (the address of) every possibly-modifed
duke@435 80 // reference field in objects in "sp". If "clear" is "true", the oops
duke@435 81 // are no longer considered possibly modified after application of the
duke@435 82 // closure. If' "before_save_marks" is true, oops in objects allocated
duke@435 83 // after the last call to "save_marks" on "sp" will not be considered.
duke@435 84 virtual void mod_oop_in_space_iterate(Space* sp, OopClosure* cl,
duke@435 85 bool clear = false,
duke@435 86 bool before_save_marks = false) = 0;
duke@435 87
duke@435 88 // Causes all refs in "mr" to be assumed to be modified.
duke@435 89 virtual void invalidate(MemRegion mr) = 0;
duke@435 90
duke@435 91 // The caller guarantees that "mr" contains no references. (Perhaps it's
duke@435 92 // objects have been moved elsewhere.)
duke@435 93 virtual void clear(MemRegion mr) = 0;
duke@435 94
duke@435 95 // Pass along the argument to the superclass.
duke@435 96 ModRefBarrierSet(int max_covered_regions) :
duke@435 97 BarrierSet(max_covered_regions) {}
duke@435 98
duke@435 99 #ifndef PRODUCT
duke@435 100 // Verifies that the given region contains no modified references.
duke@435 101 virtual void verify_clean_region(MemRegion mr) = 0;
duke@435 102 #endif
duke@435 103
duke@435 104 };

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