1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* Copyright (c) 1988 AT&T */ 23 /* All Rights Reserved */ 24 25 26 /* 27 * Copyright 2014 Garrett D'Amore <garrett@damore.org> 28 * 29 * Copyright (c) 1996, by Sun Microsystems, Inc. 30 * All Rights Reserved 31 */ 32 33 #ifndef _NAN_H 34 #define _NAN_H 35 36 /* 37 * Handling of Not_a_Number's (only in IEEE floating-point standard) 38 */ 39 40 #include <sys/isa_defs.h> 41 #include <values.h> 42 43 #ifdef __cplusplus 44 extern "C" { 45 #endif 46 47 #if defined(_IEEE_754) 48 /* 49 * Structure order is endian dependent. Only the common variants of 50 * big and little endian are supported. 51 */ 52 53 #if defined(_BIG_ENDIAN) 54 55 typedef union 56 { 57 struct 58 { 59 unsigned sign : 1; 60 unsigned exponent :11; 61 unsigned bits :20; 62 unsigned fraction_low :32; 63 } inf_parts; 64 struct 65 { 66 unsigned sign : 1; 67 unsigned exponent :11; 68 unsigned qnan_bit : 1; 69 unsigned bits :19; 70 unsigned fraction_low :32; 71 } nan_parts; 72 double d; 73 74 } dnan; 75 76 #else /* Must be _LITTLE_ENDIAN */ 77 78 typedef union 79 { 80 struct { 81 unsigned fraction_low :32; 82 unsigned bits :20; 83 unsigned exponent :11; 84 unsigned sign : 1; 85 } inf_parts; 86 struct { 87 unsigned fraction_low :32; 88 unsigned bits :19; 89 unsigned qnan_bit : 1; 90 unsigned exponent :11; 91 unsigned sign : 1; 92 } nan_parts; 93 double d; 94 } dnan; 95 96 #endif /* Endian based selection */ 97 98 /* 99 * IsNANorINF checks that exponent of double == 2047 100 * i.e. that number is a NaN or an infinity 101 */ 102 #define IsNANorINF(X) (((dnan *)&(X))->nan_parts.exponent == 0x7ff) 103 104 /* 105 * IsINF must be used after IsNANorINF has checked the exponent 106 */ 107 #define IsINF(X) (((dnan *)&(X))->inf_parts.bits == 0 && \ 108 ((dnan *)&(X))->inf_parts.fraction_low == 0) 109 110 /* 111 * IsPosNAN and IsNegNAN can be used to check the sign of infinities too 112 */ 113 #define IsPosNAN(X) (((dnan *)&(X))->nan_parts.sign == 0) 114 115 #define IsNegNAN(X) (((dnan *)&(X))->nan_parts.sign == 1) 116 117 /* 118 * GETNaNPC gets the leftmost 32 bits of the fraction part 119 */ 120 #define GETNaNPC(dval) (((dnan *)&(dval))->inf_parts.bits << 12 | \ 121 ((dnan *)&(dval))->nan_parts.fraction_low >> 20) 122 123 #define KILLFPE() (void) _kill(_getpid(), 8) 124 #define NaN(X) (((dnan *)&(X))->nan_parts.exponent == 0x7ff) 125 #define KILLNaN(X) if (NaN(X)) KILLFPE() 126 127 #else /* defined(_IEEE_754) */ 128 /* #error is strictly ansi-C, but works as well as anything for K&R systems. */ 129 #error ISA not supported 130 #endif /* defined(_IEEE_754) */ 131 132 #ifdef __cplusplus 133 } 134 #endif 135 136 #endif /* _NAN_H */ 137