Thu, 12 Jun 2008 13:50:55 -0700
Merge
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 2000-2004 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 | // A very simple data structure representing a contigous word-aligned |
duke@435 | 26 | // region of address space. |
duke@435 | 27 | |
duke@435 | 28 | #include "incls/_precompiled.incl" |
duke@435 | 29 | #include "incls/_memRegion.cpp.incl" |
duke@435 | 30 | |
duke@435 | 31 | MemRegion MemRegion::intersection(const MemRegion mr2) const { |
duke@435 | 32 | MemRegion res; |
duke@435 | 33 | HeapWord* res_start = MAX2(start(), mr2.start()); |
duke@435 | 34 | HeapWord* res_end = MIN2(end(), mr2.end()); |
duke@435 | 35 | if (res_start < res_end) { |
duke@435 | 36 | res.set_start(res_start); |
duke@435 | 37 | res.set_end(res_end); |
duke@435 | 38 | } |
duke@435 | 39 | return res; |
duke@435 | 40 | } |
duke@435 | 41 | |
duke@435 | 42 | MemRegion MemRegion::_union(const MemRegion mr2) const { |
duke@435 | 43 | // If one region is empty, return the other |
duke@435 | 44 | if (is_empty()) return mr2; |
duke@435 | 45 | if (mr2.is_empty()) return MemRegion(start(), end()); |
duke@435 | 46 | |
duke@435 | 47 | // Otherwise, regions must overlap or be adjacent |
duke@435 | 48 | assert(((start() <= mr2.start()) && (end() >= mr2.start())) || |
duke@435 | 49 | ((mr2.start() <= start()) && (mr2.end() >= start())), |
duke@435 | 50 | "non-adjacent or overlapping regions"); |
duke@435 | 51 | MemRegion res; |
duke@435 | 52 | HeapWord* res_start = MIN2(start(), mr2.start()); |
duke@435 | 53 | HeapWord* res_end = MAX2(end(), mr2.end()); |
duke@435 | 54 | res.set_start(res_start); |
duke@435 | 55 | res.set_end(res_end); |
duke@435 | 56 | return res; |
duke@435 | 57 | } |
duke@435 | 58 | |
duke@435 | 59 | MemRegion MemRegion::minus(const MemRegion mr2) const { |
duke@435 | 60 | // There seem to be 6 cases: |
duke@435 | 61 | // |this MemRegion| |
duke@435 | 62 | // |strictly below| |
duke@435 | 63 | // |overlap beginning| |
duke@435 | 64 | // |interior| |
duke@435 | 65 | // |overlap ending| |
duke@435 | 66 | // |strictly above| |
duke@435 | 67 | // |completely overlapping| |
duke@435 | 68 | // We can't deal with an interior case because it would |
duke@435 | 69 | // produce two disjoint regions as a result. |
duke@435 | 70 | // We aren't trying to be optimal in the number of tests below, |
duke@435 | 71 | // but the order is important to distinguish the strictly cases |
duke@435 | 72 | // from the overlapping cases. |
duke@435 | 73 | if (mr2.end() <= start()) { |
duke@435 | 74 | // strictly below |
duke@435 | 75 | return MemRegion(start(), end()); |
duke@435 | 76 | } |
duke@435 | 77 | if (mr2.start() <= start() && mr2.end() <= end()) { |
duke@435 | 78 | // overlap beginning |
duke@435 | 79 | return MemRegion(mr2.end(), end()); |
duke@435 | 80 | } |
duke@435 | 81 | if (mr2.start() >= end()) { |
duke@435 | 82 | // strictly above |
duke@435 | 83 | return MemRegion(start(), end()); |
duke@435 | 84 | } |
duke@435 | 85 | if (mr2.start() >= start() && mr2.end() >= end()) { |
duke@435 | 86 | // overlap ending |
duke@435 | 87 | return MemRegion(start(), mr2.start()); |
duke@435 | 88 | } |
duke@435 | 89 | if (mr2.start() <= start() && mr2.end() >= end()) { |
duke@435 | 90 | // completely overlapping |
duke@435 | 91 | return MemRegion(); |
duke@435 | 92 | } |
duke@435 | 93 | if (mr2.start() > start() && mr2.end() < end()) { |
duke@435 | 94 | // interior |
duke@435 | 95 | guarantee(false, "MemRegion::minus, but interior"); |
duke@435 | 96 | return MemRegion(); |
duke@435 | 97 | } |
duke@435 | 98 | ShouldNotReachHere(); |
duke@435 | 99 | return MemRegion(); |
duke@435 | 100 | } |