1 /*
2 * Copyright (c) 2009, 2015, 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 jdk.vm.ci.code;
24
25 import java.nio.*;
26 import java.util.*;
27
28 import jdk.vm.ci.code.Register.RegisterCategory;
29 import jdk.vm.ci.meta.*;
30
31 /**
32 * Represents a CPU architecture, including information such as its endianness, CPU registers, word
33 * width, etc.
34 */
35 public abstract class Architecture {
36
37 /**
38 * The number of entries required in a {@link ReferenceMap} covering all the registers that may
39 * store references. The index of a register in the reference map is given by
40 * {@link Register#getReferenceMapIndex()}.
41 */
42 private final int registerReferenceMapSize;
43
44 /**
45 * The architecture specific type of a native word.
46 */
47 private final PlatformKind wordKind;
48
49 /**
50 * The name of this architecture (e.g. "AMD64", "SPARCv9").
51 */
52 private final String name;
53
54 /**
55 * Array of all available registers on this architecture. The index of each register in this
56 * array is equal to its {@linkplain Register#number number}.
57 */
58 private final Register[] registers;
59
60 /**
61 * The byte ordering can be either little or big endian.
62 */
63 private final ByteOrder byteOrder;
64
65 /**
66 * Whether the architecture supports unaligned memory accesses.
67 */
68 private final boolean unalignedMemoryAccess;
69
70 /**
71 * Mask of the barrier constants denoting the barriers that are not required to be explicitly
72 * inserted under this architecture.
73 */
74 private final int implicitMemoryBarriers;
75
76 /**
77 * Offset in bytes from the beginning of a call instruction to the displacement.
78 */
79 private final int machineCodeCallDisplacementOffset;
80
81 /**
82 * The size of the return address pushed to the stack by a call instruction. A value of 0
83 * denotes that call linkage uses registers instead (e.g. SPARC).
84 */
85 private final int returnAddressSize;
86
87 protected Architecture(String name, PlatformKind wordKind, ByteOrder byteOrder, boolean unalignedMemoryAccess, Register[] registers, int implicitMemoryBarriers, int nativeCallDisplacementOffset,
88 int registerReferenceMapSize, int returnAddressSize) {
89 this.name = name;
90 this.registers = registers;
91 this.wordKind = wordKind;
92 this.byteOrder = byteOrder;
93 this.unalignedMemoryAccess = unalignedMemoryAccess;
94 this.implicitMemoryBarriers = implicitMemoryBarriers;
95 this.machineCodeCallDisplacementOffset = nativeCallDisplacementOffset;
96 this.registerReferenceMapSize = registerReferenceMapSize;
97 this.returnAddressSize = returnAddressSize;
98 }
99
100 /**
101 * Converts this architecture to a string.
102 *
103 * @return the string representation of this architecture
104 */
105 @Override
106 public final String toString() {
107 return getName().toLowerCase();
108 }
109
110 public int getRegisterReferenceMapSize() {
111 return registerReferenceMapSize;
112 }
113
114 /**
115 * Gets the natural size of words (typically registers and pointers) of this architecture, in
116 * bytes.
117 */
118 public int getWordSize() {
119 return wordKind.getSizeInBytes();
120 }
121
122 public PlatformKind getWordKind() {
123 return wordKind;
124 }
125
126 /**
127 * Gets the name of this architecture.
128 */
129 public String getName() {
130 return name;
131 }
132
133 /**
134 * Gets an array of all available registers on this architecture. The index of each register in
135 * this array is equal to its {@linkplain Register#number number}.
136 */
137 public Register[] getRegisters() {
138 return registers.clone();
139 }
140
141 public ByteOrder getByteOrder() {
142 return byteOrder;
143 }
144
145 /**
146 * @return true if the architecture supports unaligned memory accesses.
147 */
148 public boolean supportsUnalignedMemoryAccess() {
149 return unalignedMemoryAccess;
150 }
151
152 /**
153 * Gets the size of the return address pushed to the stack by a call instruction. A value of 0
154 * denotes that call linkage uses registers instead.
155 */
156 public int getReturnAddressSize() {
157 return returnAddressSize;
158 }
159
160 /**
161 * Gets the offset in bytes from the beginning of a call instruction to the displacement.
162 */
163 public int getMachineCodeCallDisplacementOffset() {
164 return machineCodeCallDisplacementOffset;
165 }
166
167 /**
168 * Determines the barriers in a given barrier mask that are explicitly required on this
169 * architecture.
170 *
171 * @param barriers a mask of the barrier constants
172 * @return the value of {@code barriers} minus the barriers unnecessary on this architecture
173 */
174 public final int requiredBarriers(int barriers) {
175 return barriers & ~implicitMemoryBarriers;
176 }
177
178 /**
179 * Determine whether a kind can be stored in a register of a given category.
180 *
181 * @param category the category of the register
182 * @param kind the kind that should be stored in the register
183 */
184 public abstract boolean canStoreValue(RegisterCategory category, PlatformKind kind);
185
186 /**
187 * Return the largest kind that can be stored in a register of a given category.
188 *
189 * @param category the category of the register
190 * @return the largest kind that can be stored in a register {@code category}
191 */
192 public abstract PlatformKind getLargestStorableKind(RegisterCategory category);
193
194 /**
195 * Return the {@link PlatformKind} that is used to store values of a given {@link JavaKind}.
196 */
197 public abstract PlatformKind getPlatformKind(JavaKind javaKind);
198
199 @Override
200 public final boolean equals(Object obj) {
201 if (obj == this) {
202 return true;
203 }
204 if (obj instanceof Architecture) {
205 Architecture that = (Architecture) obj;
206 if (this.name.equals(that.name)) {
207 assert this.byteOrder.equals(that.byteOrder);
208 assert this.implicitMemoryBarriers == that.implicitMemoryBarriers;
209 assert this.machineCodeCallDisplacementOffset == that.machineCodeCallDisplacementOffset;
210 assert this.registerReferenceMapSize == that.registerReferenceMapSize;
211 assert Arrays.equals(this.registers, that.registers);
212 assert this.returnAddressSize == that.returnAddressSize;
213 assert this.unalignedMemoryAccess == that.unalignedMemoryAccess;
214 assert this.wordKind == that.wordKind;
215 return true;
216 }
217 }
218 return false;
219 }
220
221 @Override
222 public final int hashCode() {
223 return name.hashCode();
224 }
225 }