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comparison graal/com.oracle.max.cri/src/com/oracle/max/cri/ci/CiAddress.java @ 4199:aaac4894175c

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Renamed cri packages from sun to oracle.
author Thomas Wuerthinger <thomas.wuerthinger@oracle.com>
date Tue, 03 Jan 2012 16:29:28 +0100
parents graal/com.oracle.max.cri/src/com/sun/cri/ci/CiAddress.java@9e0c1b4cfef5
children 430b5db3e6f8
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4198:8c9c0e1eaab1 4199:aaac4894175c
1 /*
2 * Copyright (c) 2010, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23 package com.oracle.max.cri.ci;
24
25 import static com.oracle.max.cri.ci.CiValueUtil.*;
26
27 /**
28 * Represents an address in target machine memory, specified via some combination of a base register, an index register,
29 * a displacement and a scale. Note that the base and index registers may be {@link CiVariable variable}, that is as yet
30 * unassigned to target machine registers.
31 */
32 public final class CiAddress extends CiValue {
33 private static final long serialVersionUID = -1003772042519945089L;
34
35 /**
36 * A sentinel value used as a place holder in an instruction stream for an address that will be patched.
37 */
38 public static final CiAddress Placeholder = new CiAddress(CiKind.Illegal, CiValue.IllegalValue);
39
40 /**
41 * Base register that defines the start of the address computation; always present.
42 */
43 public final CiValue base;
44 /**
45 * Optional index register, the value of which (possibly scaled by {@link #scale}) is added to {@link #base}.
46 * If not present, is denoted by {@link CiValue#IllegalValue}.
47 */
48 public final CiValue index;
49 /**
50 * Scaling factor for indexing, dependent on target operand size.
51 */
52 public final Scale scale;
53 /**
54 * Optional additive displacement.
55 */
56 public final int displacement;
57
58 /**
59 * Creates a {@code CiAddress} with given base register, no scaling and no displacement.
60 * @param kind the kind of the value being addressed
61 * @param base the base register
62 */
63 public CiAddress(CiKind kind, CiValue base) {
64 this(kind, base, IllegalValue, Scale.Times1, 0);
65 }
66
67 /**
68 * Creates a {@code CiAddress} with given base register, no scaling and a given displacement.
69 * @param kind the kind of the value being addressed
70 * @param base the base register
71 * @param displacement the displacement
72 */
73 public CiAddress(CiKind kind, CiValue base, int displacement) {
74 this(kind, base, IllegalValue, Scale.Times1, displacement);
75 }
76
77 /**
78 * Creates a {@code CiAddress} with given base and offset registers, no scaling and no displacement.
79 * @param kind the kind of the value being addressed
80 * @param base the base register
81 * @param offset the offset register
82 */
83 public CiAddress(CiKind kind, CiValue base, CiValue offset) {
84 this(kind, base, offset, Scale.Times1, 0);
85 }
86
87 /**
88 * Creates a {@code CiAddress} with given base and index registers, scaling and displacement.
89 * This is the most general constructor..
90 * @param kind the kind of the value being addressed
91 * @param base the base register
92 * @param index the index register
93 * @param scale the scaling factor
94 * @param displacement the displacement
95 */
96 public CiAddress(CiKind kind, CiValue base, CiValue index, Scale scale, int displacement) {
97 super(kind);
98
99 this.base = base;
100 if (isConstant(index)) {
101 long longIndex = ((CiConstant) index).asLong();
102 long longDisp = displacement + longIndex * scale.value;
103 if ((int) longIndex != longIndex || (int) longDisp != longDisp) {
104 throw new Error("integer overflow when computing constant displacement");
105 }
106 this.displacement = (int) longDisp;
107 this.index = IllegalValue;
108 this.scale = Scale.Times1;
109 } else {
110 assert isIllegal(base) || isVariable(base) || isRegister(base);
111 assert isIllegal(index) || isVariable(index) || isRegister(index);
112
113 this.index = index;
114 this.scale = scale;
115 this.displacement = displacement;
116 }
117 }
118
119 /**
120 * A scaling factor used in complex addressing modes such as those supported by x86 platforms.
121 */
122 public enum Scale {
123 Times1(1, 0),
124 Times2(2, 1),
125 Times4(4, 2),
126 Times8(8, 3);
127
128 Scale(int value, int log2) {
129 this.value = value;
130 this.log2 = log2;
131 }
132
133 /**
134 * The value (or multiplier) of this scale.
135 */
136 public final int value;
137
138 /**
139 * The {@linkplain #value value} of this scale log 2.
140 */
141 public final int log2;
142
143 public static Scale fromInt(int scale) {
144 // Checkstyle: stop
145 switch (scale) {
146 case 1: return Times1;
147 case 2: return Times2;
148 case 4: return Times4;
149 case 8: return Times8;
150 default: throw new IllegalArgumentException(String.valueOf(scale));
151 }
152 // Checkstyle: resume
153 }
154
155 public static Scale fromShift(int shift) {
156 return fromInt(1 << shift);
157 }
158 }
159
160 /**
161 * Encodes the possible addressing modes as a simple value.
162 */
163 public enum Format {
164 BASE,
165 BASE_DISP,
166 BASE_INDEX,
167 BASE_INDEX_DISP,
168 PLACEHOLDER;
169 }
170
171 /**
172 * Returns the {@link Format encoded addressing mode} that this {@code CiAddress} represents.
173 * @return the encoded addressing mode
174 */
175 public Format format() {
176 if (this == Placeholder) {
177 return Format.PLACEHOLDER;
178 }
179 assert isLegal(base);
180 if (isLegal(index)) {
181 if (displacement != 0) {
182 return Format.BASE_INDEX_DISP;
183 } else {
184 return Format.BASE_INDEX;
185 }
186 } else {
187 if (displacement != 0) {
188 return Format.BASE_DISP;
189 } else {
190 return Format.BASE;
191 }
192 }
193 }
194
195 private static String s(CiValue location) {
196 if (isRegister(location)) {
197 return asRegister(location).name;
198 }
199 assert isVariable(location);
200 return "v" + ((CiVariable) location).index;
201 }
202
203 private static String signed(int i) {
204 if (i >= 0) {
205 return "+" + i;
206 }
207 return String.valueOf(i);
208 }
209
210 @Override
211 public String toString() {
212 // Checkstyle: stop
213 switch (format()) {
214 case BASE : return "[" + s(base) + kindSuffix() + "]";
215 case BASE_DISP : return "[" + s(base) + signed(displacement) + kindSuffix() + "]";
216 case BASE_INDEX : return "[" + s(base) + "+" + s(index) + kindSuffix() + "]";
217 case BASE_INDEX_DISP : return "[" + s(base) + "+(" + s(index) + "*" + scale.value + ")" + signed(displacement) + kindSuffix() + "]";
218 case PLACEHOLDER : return "[<placeholder>]";
219 default : throw new IllegalArgumentException("unknown format: " + format());
220 }
221 // Checkstyle: resume
222 }
223
224 @Override
225 public boolean equals(Object obj) {
226 if (obj instanceof CiAddress) {
227 CiAddress addr = (CiAddress) obj;
228 return kind == addr.kind && displacement == addr.displacement && base.equals(addr.base) && scale == addr.scale && index.equals(addr.index);
229 }
230 return false;
231 }
232
233 @Override
234 public int hashCode() {
235 return (base.hashCode() << 4) | kind.ordinal();
236 }
237 }