1 /*
2 * Copyright (c) 2014, 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
24 package org.graalvm.compiler.replacements.aarch64;
25
26 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_IGNORED;
27 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_IGNORED;
28
29 import org.graalvm.compiler.api.replacements.Snippet;
30 import org.graalvm.compiler.api.replacements.SnippetReflectionProvider;
31 import org.graalvm.compiler.graph.Node.NodeIntrinsic;
32 import org.graalvm.compiler.graph.NodeClass;
33 import org.graalvm.compiler.nodeinfo.NodeInfo;
34 import org.graalvm.compiler.nodes.StructuredGraph;
35 import org.graalvm.compiler.nodes.ValueNode;
36 import org.graalvm.compiler.nodes.calc.RemNode;
37 import org.graalvm.compiler.nodes.spi.LoweringTool;
38 import org.graalvm.compiler.phases.util.Providers;
39 import org.graalvm.compiler.replacements.SnippetTemplate;
40 import org.graalvm.compiler.replacements.SnippetTemplate.Arguments;
41 import org.graalvm.compiler.replacements.Snippets;
42
43 import jdk.vm.ci.code.TargetDescription;
44 import jdk.vm.ci.meta.JavaKind;
45
46 /**
47 * AArch64 does not have a remainder operation. We use <code>n % d == n - Truncate(n / d) * d</code>
48 * for it instead. This is not correct for some edge cases, so we have to fix it up using these
49 * snippets.
50 */
51 public class AArch64FloatArithmeticSnippets extends SnippetTemplate.AbstractTemplates implements Snippets {
52
53 private final SnippetTemplate.SnippetInfo drem;
54 private final SnippetTemplate.SnippetInfo frem;
55
56 public AArch64FloatArithmeticSnippets(Providers providers, SnippetReflectionProvider snippetReflection, TargetDescription target) {
57 super(providers, snippetReflection, target);
58 drem = snippet(AArch64FloatArithmeticSnippets.class, "dremSnippet");
59 frem = snippet(AArch64FloatArithmeticSnippets.class, "fremSnippet");
60 }
61
62 public void lower(RemNode node, LoweringTool tool) {
63 JavaKind kind = node.stamp().getStackKind();
64 assert kind == JavaKind.Float || kind == JavaKind.Double;
65 if (node instanceof SafeNode) {
66 // We already introduced the necessary checks, nothing to do.
67 return;
68 }
69 SnippetTemplate.SnippetInfo snippet = kind == JavaKind.Float ? frem : drem;
70 StructuredGraph graph = node.graph();
71 Arguments args = new Arguments(snippet, graph.getGuardsStage(), tool.getLoweringStage());
72 args.add("x", node.getX());
73 args.add("y", node.getY());
74 template(args).instantiate(providers.getMetaAccess(), node, SnippetTemplate.DEFAULT_REPLACER, tool, args);
75 }
76
77 @Snippet
78 public static float fremSnippet(float x, float y) {
79 // JVMS: If either value1' or value2' is NaN, the result is NaN.
80 // JVMS: If the dividend is an infinity or the divisor is a zero or both, the result is NaN.
81 if (Float.isInfinite(x) || y == 0.0f || Float.isNaN(y)) {
82 return Float.NaN;
83 }
84 // JVMS: If the dividend is finite and the divisor is an infinity, the result equals the
85 // dividend.
86 // JVMS: If the dividend is a zero and the divisor is finite, the result equals the
87 // dividend.
88 if (x == 0.0f || Float.isInfinite(y)) {
89 return x;
90 }
91
92 float result = safeRem(x, y);
93
94 // JVMS: If neither value1' nor value2' is NaN, the sign of the result equals the sign of
95 // the dividend.
96 if (result == 0.0f && x < 0.0f) {
97 return -result;
98 }
99 return result;
100 }
101
102 @Snippet
103 public static double dremSnippet(double x, double y) {
104 // JVMS: If either value1' or value2' is NaN, the result is NaN.
105 // JVMS: If the dividend is an infinity or the divisor is a zero or both, the result is NaN.
106 if (Double.isInfinite(x) || y == 0.0 || Double.isNaN(y)) {
107 return Double.NaN;
108 }
109 // JVMS: If the dividend is finite and the divisor is an infinity, the result equals the
110 // dividend.
111 // JVMS: If the dividend is a zero and the divisor is finite, the result equals the
112 // dividend.
113 if (x == 0.0 || Double.isInfinite(y)) {
114 return x;
115 }
116
117 double result = safeRem(x, y);
118
119 // JVMS: If neither value1' nor value2' is NaN, the sign of the result equals the sign of
120 // the dividend.
121 if (result == 0.0 && x < 0.0) {
122 return -result;
123 }
124 return result;
125 }
126
127 @NodeIntrinsic(SafeFloatRemNode.class)
128 private static native float safeRem(float x, float y);
129
130 @NodeIntrinsic(SafeFloatRemNode.class)
131 private static native double safeRem(double x, double y);
132
133 /**
134 * Marker interface to distinguish untreated nodes from ones where we have installed the
135 * additional checks.
136 */
137 private interface SafeNode {
138 }
139
140 @NodeInfo(cycles = CYCLES_IGNORED, size = SIZE_IGNORED)
141 // static class SafeFloatRemNode extends FloatRemNode implements SafeNode {
142 static class SafeFloatRemNode extends RemNode implements SafeNode {
143 public static final NodeClass<SafeFloatRemNode> TYPE = NodeClass.create(SafeFloatRemNode.class);
144
145 protected SafeFloatRemNode(ValueNode x, ValueNode y) {
146 super(TYPE, x, y);
147 }
148 }
149
150 }