/*
* 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.ppc;
import com.sun.max.asm.*;
import com.sun.max.util.*;
/**
* The constants denoting the eight 4-bit fields into which the 32-bit Condition Register
* is logically partitioned.
*/
public enum CRF implements EnumerableArgument<CRF> {
CR0, CR1, CR2, CR3, CR4, CR5, CR6, CR7;
/**
* Determines if a mask of bits only selects one of the 8 condition register fields.
*/
public static boolean isExactlyOneCRFSelected(int mask) {
return (mask & (mask - 1)) == 0 && mask > 0 && mask <= 128;
}
public int value() {
return ordinal();
}
public long asLong() {
return value();
}
public String externalValue() {
return Integer.toString(ordinal());
}
public String disassembledValue() {
return externalValue();
}
public Enumerator<CRF> enumerator() {
return ENUMERATOR;
}
public CRF exampleValue() {
return CR0;
}
/**
* Given the index of a bit within this 4-bit field, returns the index of the same bit
* in the 32-bit Condition Register.
*
* @throws IllegalArgumentException if n is not between 0 and 3 inclusive
*/
public int bitFor(int n) {
if (n < 0 || n > 3) {
throw new IllegalArgumentException("bit specifier must be between 0 and 3");
}
return ordinal() * 4 + n;
}
/**
* @return the index of the bit within the 32-bit Condition Register corresponding to the <i>less than</i> bit in this Condition Register field
*/
public int lt() {
return bitFor(LT);
}
/**
* @return the index of the bit within the 32-bit Condition Register corresponding to the <i>greater than</i> bit in this Condition Register field
*/
public int gt() {
return bitFor(GT);
}
/**
* @return the index of the bit within the 32-bit Condition Register corresponding to the <i>equal</i> bit in this Condition Register field
*/
public int eq() {
return bitFor(EQ);
}
/**
* @return the index of the bit within the 32-bit Condition Register corresponding to the <i>summary overflow</i> bit in this Condition Register field
*/
public int so() {
return bitFor(SO);
}
/**
* @return the index of the bit within the 32-bit Condition Register corresponding to the <i>unordered (after floating-point comparison)</i> bit in this Condition Register field
*/
public int un() {
return bitFor(UN);
}
/**
* Index of the bit in a 4-bit Condition Register field indicating a <i>less than</i> condition.
*/
public static final int LT = 0;
/**
* Index of the bit in a 4-bit Condition Register field indicating a <i>greater than</i> condition.
*/
public static final int GT = 1;
/**
* Index of the bit in a 4-bit Condition Register field indicating an <i>equal</i> condition.
*/
public static final int EQ = 2;
/**
* Index of the bit in a 4-bit Condition Register field indicating a <i>summary overflow</i> condition.
*/
public static final int SO = 3;
/**
* Index of the bit in a 4-bit Condition Register field indicating an <i>unordered (after floating-point comparison)</i> condition.
*/
public static final int UN = 3;
public static final Enumerator<CRF> ENUMERATOR = new Enumerator<CRF>(CRF.class);
}