Sun, 13 Apr 2008 17:43:42 -0400
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
Summary: Compressed oops in instances, arrays, and headers. Code contributors are coleenp, phh, never, swamyv
Reviewed-by: jmasa, kamg, acorn, tbell, kvn, rasbold
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 2000-2002 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 | }; |