Mercurial > hg > graal-jvmci-8
view graal/com.oracle.jvmci.asm.amd64/src/com/oracle/jvmci/asm/amd64/AMD64Address.java @ 21711:1c41d00e6b2f
moved com.oracle.graal.bytecode to JVMCI namespace (JBS:GRAAL-53)
author | Doug Simon <doug.simon@oracle.com> |
---|---|
date | Wed, 03 Jun 2015 21:42:01 +0200 |
parents | 6df25b1418be |
children |
line wrap: on
line source
/* * Copyright (c) 2010, 2013, 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.oracle.jvmci.asm.amd64; import com.oracle.jvmci.code.Register; import com.oracle.jvmci.code.AbstractAddress; /** * Represents an address in target machine memory, specified via some combination of a base * register, an index register, a displacement and a scale. Note that the base and index registers * may be a variable that will get a register assigned later by the register allocator. */ public final class AMD64Address extends AbstractAddress { private final Register base; private final Register index; private final Scale scale; private final int displacement; /** * Creates an {@link AMD64Address} with given base register, no scaling and no displacement. * * @param base the base register */ public AMD64Address(Register base) { this(base, Register.None, Scale.Times1, 0); } /** * Creates an {@link AMD64Address} with given base register, no scaling and a given * displacement. * * @param base the base register * @param displacement the displacement */ public AMD64Address(Register base, int displacement) { this(base, Register.None, Scale.Times1, displacement); } /** * Creates an {@link AMD64Address} with given base and index registers, scaling and * displacement. This is the most general constructor. * * @param base the base register * @param index the index register * @param scale the scaling factor * @param displacement the displacement */ public AMD64Address(Register base, Register index, Scale scale, int displacement) { this.base = base; this.index = index; this.scale = scale; this.displacement = displacement; assert scale != null; } /** * A scaling factor used in the SIB addressing mode. */ public enum Scale { Times1(1, 0), Times2(2, 1), Times4(4, 2), Times8(8, 3); private Scale(int value, int log2) { this.value = value; this.log2 = log2; } /** * The value (or multiplier) of this scale. */ public final int value; /** * The {@linkplain #value value} of this scale log 2. */ public final int log2; public static Scale fromInt(int scale) { switch (scale) { case 1: return Times1; case 2: return Times2; case 4: return Times4; case 8: return Times8; default: return null; } } } @Override public String toString() { StringBuilder s = new StringBuilder(); s.append("["); String sep = ""; if (!getBase().equals(Register.None)) { s.append(getBase()); sep = " + "; } if (!getIndex().equals(Register.None)) { s.append(sep).append(getIndex()).append(" * ").append(getScale().value); sep = " + "; } if (getDisplacement() < 0) { s.append(" - ").append(-getDisplacement()); } else if (getDisplacement() > 0) { s.append(sep).append(getDisplacement()); } s.append("]"); return s.toString(); } /** * @return Base register that defines the start of the address computation. If not present, is * denoted by {@link Register#None}. */ public Register getBase() { return base; } /** * @return Index register, the value of which (possibly scaled by {@link #getScale}) is added to * {@link #getBase}. If not present, is denoted by {@link Register#None}. */ public Register getIndex() { return index; } /** * @return Scaling factor for indexing, dependent on target operand size. */ public Scale getScale() { return scale; } /** * @return Optional additive displacement. */ public int getDisplacement() { return displacement; } }