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.options.OptionValues;
39 import org.graalvm.compiler.phases.util.Providers;
40 import org.graalvm.compiler.replacements.SnippetTemplate;
41 import org.graalvm.compiler.replacements.SnippetTemplate.Arguments;
42 import org.graalvm.compiler.replacements.Snippets;
43
44 import jdk.vm.ci.code.TargetDescription;
45 import jdk.vm.ci.meta.JavaKind;
46
47 /**
48 * AArch64 does not have a remainder operation. We use <code>n % d == n - Truncate(n / d) * d</code>
49 * for it instead. This is not correct for some edge cases, so we have to fix it up using these
50 * snippets.
51 */
52 public class AArch64FloatArithmeticSnippets extends SnippetTemplate.AbstractTemplates implements Snippets {
53
54 private final SnippetTemplate.SnippetInfo drem;
55 private final SnippetTemplate.SnippetInfo frem;
56
57 public AArch64FloatArithmeticSnippets(OptionValues options, Providers providers, SnippetReflectionProvider snippetReflection, TargetDescription target) {
58 super(options, providers, snippetReflection, target);
59 drem = snippet(AArch64FloatArithmeticSnippets.class, "dremSnippet");
60 frem = snippet(AArch64FloatArithmeticSnippets.class, "fremSnippet");
61 }
62
63 public void lower(RemNode node, LoweringTool tool) {
64 JavaKind kind = node.stamp().getStackKind();
65 assert kind == JavaKind.Float || kind == JavaKind.Double;
66 if (node instanceof SafeNode) {
67 // We already introduced the necessary checks, nothing to do.
68 return;
69 }
70 SnippetTemplate.SnippetInfo snippet = kind == JavaKind.Float ? frem : drem;
71 StructuredGraph graph = node.graph();
72 Arguments args = new Arguments(snippet, graph.getGuardsStage(), tool.getLoweringStage());
73 args.add("x", node.getX());
74 args.add("y", node.getY());
75 template(args).instantiate(providers.getMetaAccess(), node, SnippetTemplate.DEFAULT_REPLACER, tool, args);
76 }
77
78 @Snippet
79 public static float fremSnippet(float x, float y) {
80 // JVMS: If either value1' or value2' is NaN, the result is NaN.
81 // JVMS: If the dividend is an infinity or the divisor is a zero or both, the result is NaN.
82 if (Float.isInfinite(x) || y == 0.0f || Float.isNaN(y)) {
83 return Float.NaN;
84 }
85 // JVMS: If the dividend is finite and the divisor is an infinity, the result equals the
86 // dividend.
87 // JVMS: If the dividend is a zero and the divisor is finite, the result equals the
88 // dividend.
89 if (x == 0.0f || Float.isInfinite(y)) {
90 return x;
91 }
92
93 float result = safeRem(x, y);
94
95 // JVMS: If neither value1' nor value2' is NaN, the sign of the result equals the sign of
96 // the dividend.
97 if (result == 0.0f && x < 0.0f) {
98 return -result;
99 }
100 return result;
101 }
102
103 @Snippet
104 public static double dremSnippet(double x, double y) {
105 // JVMS: If either value1' or value2' is NaN, the result is NaN.
106 // JVMS: If the dividend is an infinity or the divisor is a zero or both, the result is NaN.
107 if (Double.isInfinite(x) || y == 0.0 || Double.isNaN(y)) {
108 return Double.NaN;
109 }
110 // JVMS: If the dividend is finite and the divisor is an infinity, the result equals the
111 // dividend.
112 // JVMS: If the dividend is a zero and the divisor is finite, the result equals the
113 // dividend.
114 if (x == 0.0 || Double.isInfinite(y)) {
115 return x;
116 }
117
118 double result = safeRem(x, y);
119
120 // JVMS: If neither value1' nor value2' is NaN, the sign of the result equals the sign of
121 // the dividend.
122 if (result == 0.0 && x < 0.0) {
123 return -result;
124 }
125 return result;
126 }
127
128 @NodeIntrinsic(SafeFloatRemNode.class)
129 private static native float safeRem(float x, float y);
130
131 @NodeIntrinsic(SafeFloatRemNode.class)
132 private static native double safeRem(double x, double y);
133
134 /**
135 * Marker interface to distinguish untreated nodes from ones where we have installed the
136 * additional checks.
137 */
138 private interface SafeNode {
139 }
140
141 @NodeInfo(cycles = CYCLES_IGNORED, size = SIZE_IGNORED)
142 // static class SafeFloatRemNode extends FloatRemNode implements SafeNode {
143 static class SafeFloatRemNode extends RemNode implements SafeNode {
144 public static final NodeClass<SafeFloatRemNode> TYPE = NodeClass.create(SafeFloatRemNode.class);
145
146 protected SafeFloatRemNode(ValueNode x, ValueNode y) {
147 super(TYPE, x, y);
148 }
149 }
150
151 }