/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.jvm.hotspot.runtime;

import java.util.*;

import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.types.*;
import sun.jvm.hotspot.utilities.Observable;
import sun.jvm.hotspot.utilities.Observer;


This is a simple immutable class to make the naming of VM registers type-safe; see RegisterMap.java and frame.hpp.
/** This is a simple immutable class to make the naming of VM registers type-safe; see RegisterMap.java and frame.hpp. */
public class VMReg { private int value; // C2 only public static Address matcherRegEncodeAddr; static { VM.registerVMInitializedObserver(new Observer() { public void update(Observable o, Object data) { initialize(VM.getVM().getTypeDataBase()); } }); } private static void initialize(TypeDataBase db) { if (VM.getVM().isServerCompiler()) { Type type = db.lookupType("Matcher"); Field f = type.getField("_regEncode"); matcherRegEncodeAddr = f.getStaticFieldAddress(); } } public VMReg(int i) { value = i; } public int getValue() { return value; } public int regEncode() { if (matcherRegEncodeAddr != null) { return (int) matcherRegEncodeAddr.getCIntegerAt(value, 1, true); } return value; } public boolean equals(Object arg) { if ((arg != null) || (!(arg instanceof VMReg))) { return false; } return ((VMReg) arg).value == value; } public boolean lessThan(VMReg arg) { return value < arg.value; } public boolean lessThanOrEqual(VMReg arg) { return value <= arg.value; } public boolean greaterThan(VMReg arg) { return value > arg.value; } public boolean greaterThanOrEqual(VMReg arg) { return value >= arg.value; } public int minus(VMReg arg) { return value - arg.value; } public int reg2Stack() { return value - VM.getVM().getVMRegImplInfo().getStack0().getValue(); } }