Mercurial > hg > truffle
view graal/com.oracle.max.asmdis/src/com/sun/max/asm/gen/risc/bitRange/DescendingBitRange.java @ 4138:82af018d61db
Merge fixes.
author | Thomas Wuerthinger <thomas.wuerthinger@oracle.com> |
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date | Sat, 17 Dec 2011 22:03:44 +0100 |
parents | e233f5660da4 |
children |
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/* * Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.sun.max.asm.gen.risc.bitRange; /** * A bit range that has its most significant bit on the left and its least significant bit on the right. */ public class DescendingBitRange extends SimpleBitRange { public DescendingBitRange(int firstIndex, int lastIndex) { super(firstIndex, lastIndex); if (firstIndex < lastIndex) { throw new IllegalArgumentException("bit ranges are specified from left to right, and descending notation starts at 31 and goes down to 0"); } } @Override public DescendingBitRange move(boolean left, int bits) { if (left) { return new DescendingBitRange(firstBitIndex + bits, lastBitIndex + bits); } return new DescendingBitRange(firstBitIndex - bits, lastBitIndex - bits); } @Override public int numberOfLessSignificantBits() { return lastBitIndex; } @Override public int width() { return (firstBitIndex - lastBitIndex) + 1; } }