1 /*
2  * Copyright (c) 1997, 2005, 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.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 #include "jni.h"
27 #include "jvm.h"
28 
29 #include <nativehelper/JNIHelp.h>
30 
31 #define NATIVE_METHOD(className, functionName, signature) \
32 { #functionName, signature, (void*)(className ## _ ## functionName) }
33 
34 
35 /*
36  * Find the float corresponding to a given bit pattern
37  */
38 JNIEXPORT jfloat JNICALL
Float_intBitsToFloat(JNIEnv * env,jclass unused,jint v)39 Float_intBitsToFloat(JNIEnv *env, jclass unused, jint v)
40 {
41     union {
42         int i;
43         float f;
44     } u;
45     u.i = (long)v;
46     return (jfloat)u.f;
47 }
48 
49 /*
50  * Find the bit pattern corresponding to a given float, NOT collapsing NaNs
51  */
52 JNIEXPORT jint JNICALL
Float_floatToRawIntBits(JNIEnv * env,jclass unused,jfloat v)53 Float_floatToRawIntBits(JNIEnv *env, jclass unused, jfloat v)
54 {
55     union {
56         int i;
57         float f;
58     } u;
59     u.f = (float)v;
60     return (jint)u.i;
61 }
62 static JNINativeMethod gMethods[] = {
63   NATIVE_METHOD(Float, intBitsToFloat, "(I)F"),
64   NATIVE_METHOD(Float, floatToRawIntBits, "(F)I"),
65 };
66 
register_java_lang_Float(JNIEnv * env)67 void register_java_lang_Float(JNIEnv* env) {
68   jniRegisterNativeMethods(env, "java/lang/Float", gMethods, NELEM(gMethods));
69 }
70