| 1 | /* $NetBSD: ieee.h,v 1.13 2024/01/02 19:28:25 christos Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 1992, 1993 |
| 5 | * The Regents of the University of California. All rights reserved. |
| 6 | * |
| 7 | * This software was developed by the Computer Systems Engineering group |
| 8 | * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and |
| 9 | * contributed to Berkeley. |
| 10 | * |
| 11 | * All advertising materials mentioning features or use of this software |
| 12 | * must display the following acknowledgement: |
| 13 | * This product includes software developed by the University of |
| 14 | * California, Lawrence Berkeley Laboratory. |
| 15 | * |
| 16 | * Redistribution and use in source and binary forms, with or without |
| 17 | * modification, are permitted provided that the following conditions |
| 18 | * are met: |
| 19 | * 1. Redistributions of source code must retain the above copyright |
| 20 | * notice, this list of conditions and the following disclaimer. |
| 21 | * 2. Redistributions in binary form must reproduce the above copyright |
| 22 | * notice, this list of conditions and the following disclaimer in the |
| 23 | * documentation and/or other materials provided with the distribution. |
| 24 | * 3. Neither the name of the University nor the names of its contributors |
| 25 | * may be used to endorse or promote products derived from this software |
| 26 | * without specific prior written permission. |
| 27 | * |
| 28 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 29 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 30 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 31 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 32 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 33 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 34 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 35 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 36 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 37 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 38 | * SUCH DAMAGE. |
| 39 | * |
| 40 | * @(#)ieee.h 8.1 (Berkeley) 6/11/93 |
| 41 | */ |
| 42 | #ifndef _X86_IEEE_H_ |
| 43 | #define _X86_IEEE_H_ |
| 44 | |
| 45 | /* |
| 46 | * ieee.h defines the machine-dependent layout of the machine's IEEE |
| 47 | * floating point. It does *not* define (yet?) any of the rounding |
| 48 | * mode bits, exceptions, and so forth. |
| 49 | */ |
| 50 | |
| 51 | #include <sys/ieee754.h> |
| 52 | |
| 53 | #define EXT_EXPBITS 15 |
| 54 | #define EXT_FRACHBITS 32 |
| 55 | #define EXT_FRACLBITS 32 |
| 56 | #define EXT_FRACBITS (EXT_FRACLBITS + EXT_FRACHBITS) |
| 57 | |
| 58 | #define EXT_TO_ARRAY32(u, a) do { \ |
| 59 | (a)[0] = (uint32_t)(u).extu_ext.ext_fracl; \ |
| 60 | (a)[1] = (uint32_t)(u).extu_ext.ext_frach; \ |
| 61 | } while(/*CONSTCOND*/0) |
| 62 | |
| 63 | /* |
| 64 | * struct ieee_ext is the raw storage layout of the 80-bit |
| 65 | * extended-precision type as implemented by the FPU. Per the |
| 66 | * respective ABI specifications, it is followed by a tail padding of |
| 67 | * |
| 68 | * amd64: 48 bits, |
| 69 | * i386: 16 bits. |
| 70 | */ |
| 71 | struct ieee_ext { |
| 72 | uint32_t ext_fracl:EXT_FRACLBITS; |
| 73 | uint32_t ext_frach:EXT_FRACHBITS; |
| 74 | #if 0 |
| 75 | uint32_t ext_int:1; |
| 76 | #endif |
| 77 | uint32_t ext_exp:EXT_EXPBITS; |
| 78 | uint32_t ext_sign:1; |
| 79 | }; |
| 80 | |
| 81 | /* |
| 82 | * Floats whose exponent is in [1..INFNAN) (of whatever type) are |
| 83 | * `normal'. Floats whose exponent is INFNAN are either Inf or NaN. |
| 84 | * Floats whose exponent is zero are either zero (iff all fraction |
| 85 | * bits are zero) or subnormal values. |
| 86 | * |
| 87 | * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its |
| 88 | * high fraction; if the bit is set, it is a `quiet NaN'. |
| 89 | */ |
| 90 | #define EXT_EXP_INFNAN 0x7fff |
| 91 | #define EXT_EXP_INF 0x7fff |
| 92 | #define EXT_EXP_NAN 0x7fff |
| 93 | |
| 94 | #if 0 |
| 95 | #define SNG_QUIETNAN (1 << 22) |
| 96 | #define DBL_QUIETNAN (1 << 19) |
| 97 | #define EXT_QUIETNAN (1 << 30) |
| 98 | #endif |
| 99 | |
| 100 | /* |
| 101 | * Exponent biases. |
| 102 | */ |
| 103 | #define EXT_EXP_BIAS 16383 |
| 104 | |
| 105 | /* |
| 106 | * Convenience data structures. |
| 107 | */ |
| 108 | union ieee_ext_u { |
| 109 | long double extu_ld; |
| 110 | struct ieee_ext extu_ext; |
| 111 | }; |
| 112 | |
| 113 | #define extu_exp extu_ext.ext_exp |
| 114 | #define extu_sign extu_ext.ext_sign |
| 115 | #define extu_fracl extu_ext.ext_fracl |
| 116 | #define extu_frach extu_ext.ext_frach |
| 117 | |
| 118 | #define LDBL_NBIT 0x80000000 |
| 119 | #define mask_nbit_l(u) ((u).extu_frach &= ~LDBL_NBIT) |
| 120 | |
| 121 | #endif /* _X86_IEEE_H_ */ |