1 /*
2 * Copyright (c) 2014, 2016, 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 org.graalvm.compiler.hotspot.nodes;
24
25 import static org.graalvm.compiler.core.common.GraalOptions.GeneratePIC;
26 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2;
27 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2;
28
29 import org.graalvm.compiler.core.common.type.AbstractObjectStamp;
30 import org.graalvm.compiler.core.common.type.ObjectStamp;
31 import org.graalvm.compiler.core.common.type.Stamp;
32 import org.graalvm.compiler.debug.GraalError;
33 import org.graalvm.compiler.graph.NodeClass;
34 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
35 import org.graalvm.compiler.hotspot.CompressEncoding;
36 import org.graalvm.compiler.hotspot.HotSpotLIRGenerator;
37 import org.graalvm.compiler.hotspot.nodes.type.KlassPointerStamp;
38 import org.graalvm.compiler.hotspot.nodes.type.NarrowOopStamp;
39 import org.graalvm.compiler.nodeinfo.NodeInfo;
40 import org.graalvm.compiler.nodes.ConstantNode;
41 import org.graalvm.compiler.nodes.ValueNode;
42 import org.graalvm.compiler.nodes.calc.ConvertNode;
43 import org.graalvm.compiler.nodes.calc.UnaryNode;
44 import org.graalvm.compiler.nodes.spi.LIRLowerable;
45 import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
46 import org.graalvm.compiler.nodes.type.StampTool;
47
48 import jdk.vm.ci.hotspot.HotSpotCompressedNullConstant;
49 import jdk.vm.ci.hotspot.HotSpotConstant;
50 import jdk.vm.ci.meta.Constant;
51 import jdk.vm.ci.meta.ConstantReflectionProvider;
52 import jdk.vm.ci.meta.JavaConstant;
53 import jdk.vm.ci.meta.Value;
54
55 /**
56 * Compress or uncompress an oop or metaspace pointer.
57 */
58 @NodeInfo(nameTemplate = "{p#op/s}", cycles = CYCLES_2, size = SIZE_2)
59 public final class CompressionNode extends UnaryNode implements ConvertNode, LIRLowerable {
60
61 public static final NodeClass<CompressionNode> TYPE = NodeClass.create(CompressionNode.class);
62
63 public enum CompressionOp {
64 Compress,
65 Uncompress
66 }
67
68 protected final CompressionOp op;
69 protected final CompressEncoding encoding;
70
71 public CompressionNode(CompressionOp op, ValueNode input, CompressEncoding encoding) {
72 super(TYPE, mkStamp(op, input.stamp(), encoding), input);
73 this.op = op;
74 this.encoding = encoding;
75 }
76
77 @Override
78 public Stamp foldStamp(Stamp newStamp) {
79 assert newStamp.isCompatible(getValue().stamp());
80 return mkStamp(op, newStamp, encoding);
81 }
82
83 public static CompressionNode compress(ValueNode input, CompressEncoding encoding) {
84 return input.graph().unique(new CompressionNode(CompressionOp.Compress, input, encoding));
85 }
86
87 public static CompressionNode compressNoUnique(ValueNode input, CompressEncoding encoding) {
88 return new CompressionNode(CompressionOp.Compress, input, encoding);
89 }
90
91 public static CompressionNode uncompress(ValueNode input, CompressEncoding encoding) {
92 return input.graph().unique(new CompressionNode(CompressionOp.Uncompress, input, encoding));
93 }
94
95 private static Constant compress(Constant c) {
96 if (JavaConstant.NULL_POINTER.equals(c)) {
97 return HotSpotCompressedNullConstant.COMPRESSED_NULL;
98 } else if (c instanceof HotSpotConstant) {
99 return ((HotSpotConstant) c).compress();
100 } else {
101 throw GraalError.shouldNotReachHere("invalid constant input for compress op: " + c);
102 }
103 }
104
105 private static Constant uncompress(Constant c) {
106 if (c instanceof HotSpotConstant) {
107 return ((HotSpotConstant) c).uncompress();
108 } else {
109 throw GraalError.shouldNotReachHere("invalid constant input for uncompress op: " + c);
110 }
111 }
112
113 @Override
114 public Constant convert(Constant c, ConstantReflectionProvider constantReflection) {
115 switch (op) {
116 case Compress:
117 return compress(c);
118 case Uncompress:
119 return uncompress(c);
120 default:
121 throw GraalError.shouldNotReachHere();
122 }
123 }
124
125 @Override
126 public Constant reverse(Constant c, ConstantReflectionProvider constantReflection) {
127 switch (op) {
128 case Compress:
129 return uncompress(c);
130 case Uncompress:
131 return compress(c);
132 default:
133 throw GraalError.shouldNotReachHere();
134 }
135 }
136
137 @Override
138 public boolean isLossless() {
139 return true;
140 }
141
142 private static Stamp mkStamp(CompressionOp op, Stamp input, CompressEncoding encoding) {
143 switch (op) {
144 case Compress:
145 if (input instanceof ObjectStamp) {
146 // compressed oop
147 return NarrowOopStamp.compressed((ObjectStamp) input, encoding);
148 } else if (input instanceof KlassPointerStamp) {
149 // compressed klass pointer
150 return ((KlassPointerStamp) input).compressed(encoding);
151 }
152 break;
153 case Uncompress:
154 if (input instanceof NarrowOopStamp) {
155 // oop
156 assert encoding.equals(((NarrowOopStamp) input).getEncoding());
157 return ((NarrowOopStamp) input).uncompressed();
158 } else if (input instanceof KlassPointerStamp) {
159 // metaspace pointer
160 assert encoding.equals(((KlassPointerStamp) input).getEncoding());
161 return ((KlassPointerStamp) input).uncompressed();
162 }
163 break;
164 }
165 throw GraalError.shouldNotReachHere(String.format("Unexpected input stamp %s", input));
166 }
167
168 public CompressionOp getOp() {
169 return op;
170 }
171
172 public CompressEncoding getEncoding() {
173 return encoding;
174 }
175
176 @Override
177 public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) {
178 if (forValue.isConstant()) {
179 if (GeneratePIC.getValue()) {
180 // We always want uncompressed constants
181 return this;
182 }
183 int stableDimension = ((ConstantNode) forValue).getStableDimension();
184 boolean isDefaultStable = ((ConstantNode) forValue).isDefaultStable();
185 return ConstantNode.forConstant(stamp(), convert(forValue.asConstant(), tool.getConstantReflection()), stableDimension, isDefaultStable, tool.getMetaAccess());
186 } else if (forValue instanceof CompressionNode) {
187 CompressionNode other = (CompressionNode) forValue;
188 if (op != other.op && encoding.equals(other.encoding)) {
189 return other.getValue();
190 }
191 }
192 return this;
193 }
194
195 @Override
196 public void generate(NodeLIRBuilderTool gen) {
197 HotSpotLIRGenerator hsGen = (HotSpotLIRGenerator) gen.getLIRGeneratorTool();
198 boolean nonNull;
199 if (getValue().stamp() instanceof AbstractObjectStamp) {
200 nonNull = StampTool.isPointerNonNull(getValue().stamp());
201 } else {
202 // metaspace pointers are never null
203 nonNull = true;
204 }
205
206 Value result;
207 switch (op) {
208 case Compress:
209 result = hsGen.emitCompress(gen.operand(getValue()), encoding, nonNull);
210 break;
211 case Uncompress:
212 result = hsGen.emitUncompress(gen.operand(getValue()), encoding, nonNull);
213 break;
214 default:
215 throw GraalError.shouldNotReachHere();
216 }
217 gen.setResult(this, result);
218 }
219
220 @NodeIntrinsic
221 public static native Object compression(@ConstantNodeParameter CompressionOp op, Object object, @ConstantNodeParameter CompressEncoding encoding);
222 }