1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 /**
18  * A few tests of Math.abs for floating-point data.
19  *
20  * Note, as a "quality of implementation", rather than pure "spec compliance",
21  * we require that Math.abs() clears the sign bit (but changes nothing else)
22  * for all numbers, including NaN (signaling NaN may become quiet though).
23  */
24 public class Main {
25 
26   private static final int SPQUIET = 1 << 22;
27   private static final long DPQUIET = 1L << 51;
28 
29   public static boolean doThrow = false;
30 
31   /// CHECK-START: float Main.$opt$noinline$absSP(float) intrinsics_recognition (after)
32   /// CHECK-DAG: <<Result:f\d+>> InvokeStaticOrDirect intrinsic:MathAbsFloat
33   /// CHECK-DAG:                 Return [<<Result>>]
$opt$noinline$absSP(float f)34   private static float $opt$noinline$absSP(float f) {
35     if (doThrow) {
36       throw new Error("Something to prevent inlining");
37     }
38     return Math.abs(f);
39   }
40 
41   /// CHECK-START: double Main.$opt$noinline$absDP(double) intrinsics_recognition (after)
42   /// CHECK-DAG: <<Result:d\d+>> InvokeStaticOrDirect intrinsic:MathAbsDouble
43   /// CHECK-DAG:                 Return [<<Result>>]
$opt$noinline$absDP(double d)44   private static double $opt$noinline$absDP(double d) {
45     if (doThrow) {
46       throw new Error("Something to prevent inlining");
47     }
48     return Math.abs(d);
49   }
50 
main(String args[])51   public static void main(String args[]) {
52     // A few obvious numbers.
53     for (float f = -100.0f; f < 0.0f; f += 0.5f) {
54       expectEqualsSP(-f, $opt$noinline$absSP(f));
55     }
56     for (float f = 0.0f; f <= 100.0f; f += 0.5f) {
57       expectEqualsSP(f, $opt$noinline$absSP(f));
58     }
59     for (float f = -1.5f; f <= -1.499f; f = Math.nextAfter(f, Float.POSITIVE_INFINITY)) {
60       expectEqualsSP(-f, $opt$noinline$absSP(f));
61     }
62     for (float f = 1.499f; f <= 1.5f; f = Math.nextAfter(f, Float.POSITIVE_INFINITY)) {
63       expectEqualsSP(f, $opt$noinline$absSP(f));
64     }
65 
66     // Zero
67     expectEquals32(0, Float.floatToRawIntBits($opt$noinline$absSP(+0.0f)));
68     expectEquals32(0, Float.floatToRawIntBits($opt$noinline$absSP(-0.0f)));
69 
70     // Inf.
71     expectEqualsSP(Float.POSITIVE_INFINITY, $opt$noinline$absSP(Float.NEGATIVE_INFINITY));
72     expectEqualsSP(Float.POSITIVE_INFINITY, $opt$noinline$absSP(Float.POSITIVE_INFINITY));
73 
74     // A few NaN numbers.
75     int[] spnans = {
76       0x7f800001,
77       0x7fa00000,
78       0x7fc00000,
79       0x7fffffff,
80       0xff800001,
81       0xffa00000,
82       0xffc00000,
83       0xffffffff
84     };
85     for (int i = 0; i < spnans.length; i++) {
86       float f = Float.intBitsToFloat(spnans[i]);
87       expectEqualsNaN32(
88           spnans[i] & Integer.MAX_VALUE,
89           Float.floatToRawIntBits($opt$noinline$absSP(f)));
90     }
91 
92     // A few obvious numbers.
93     for (double d = -100.0; d < 0.0; d += 0.5) {
94       expectEqualsDP(-d, $opt$noinline$absDP(d));
95     }
96     for (double d = 0.0; d <= 100.0; d += 0.5) {
97       expectEqualsDP(d, $opt$noinline$absDP(d));
98     }
99     for (double d = -1.5d; d <= -1.49999999999d; d = Math.nextAfter(d, Double.POSITIVE_INFINITY)) {
100       expectEqualsDP(-d, $opt$noinline$absDP(d));
101     }
102     for (double d = 1.49999999999d; d <= 1.5; d = Math.nextAfter(d, Double.POSITIVE_INFINITY)) {
103       expectEqualsDP(d, $opt$noinline$absDP(d));
104     }
105 
106     // Zero
107     expectEquals64(0L, Double.doubleToRawLongBits($opt$noinline$absDP(+0.0f)));
108     expectEquals64(0L, Double.doubleToRawLongBits($opt$noinline$absDP(-0.0f)));
109 
110     // Inf.
111     expectEqualsDP(Double.POSITIVE_INFINITY, $opt$noinline$absDP(Double.NEGATIVE_INFINITY));
112     expectEqualsDP(Double.POSITIVE_INFINITY, $opt$noinline$absDP(Double.POSITIVE_INFINITY));
113 
114     // A few NaN numbers.
115     long[] dpnans = {
116       0x7ff0000000000001L,
117       0x7ff4000000000000L,
118       0x7ff8000000000000L,
119       0x7fffffffffffffffL,
120       0xfff0000000000001L,
121       0xfff4000000000000L,
122       0xfff8000000000000L,
123       0xffffffffffffffffL
124     };
125     for (int i = 0; i < dpnans.length; i++) {
126       double d = Double.longBitsToDouble(dpnans[i]);
127       expectEqualsNaN64(
128           dpnans[i] & Long.MAX_VALUE,
129           Double.doubleToRawLongBits($opt$noinline$absDP(d)));
130     }
131 
132     System.out.println("passed");
133   }
134 
expectEquals32(int expected, int result)135   private static void expectEquals32(int expected, int result) {
136     if (expected != result) {
137       throw new Error("Expected: 0x" + Integer.toHexString(expected)
138           + ", found: 0x" + Integer.toHexString(result));
139     }
140   }
141 
142   // We allow that an expected NaN result has become quiet.
expectEqualsNaN32(int expected, int result)143   private static void expectEqualsNaN32(int expected, int result) {
144     if (expected != result && (expected | SPQUIET) != result) {
145       throw new Error("Expected: 0x" + Integer.toHexString(expected)
146           + ", found: 0x" + Integer.toHexString(result));
147     }
148   }
149 
expectEquals64(long expected, long result)150   private static void expectEquals64(long expected, long result) {
151     if (expected != result) {
152       throw new Error("Expected: 0x" + Long.toHexString(expected)
153           + ", found: 0x" + Long.toHexString(result));
154     }
155   }
156 
157   // We allow that an expected NaN result has become quiet.
expectEqualsNaN64(long expected, long result)158   private static void expectEqualsNaN64(long expected, long result) {
159     if (expected != result && (expected | DPQUIET) != result) {
160       throw new Error("Expected: 0x" + Long.toHexString(expected)
161           + ", found: 0x" + Long.toHexString(result));
162     }
163   }
164 
expectEqualsSP(float expected, float result)165   private static void expectEqualsSP(float expected, float result) {
166     if (expected != result) {
167       throw new Error("Expected: " + expected + ", found: " + result);
168     }
169   }
170 
expectEqualsDP(double expected, double result)171   private static void expectEqualsDP(double expected, double result) {
172     if (expected != result) {
173       throw new Error("Expected: " + expected + ", found: " + result);
174     }
175   }
176 }
177