fpu.h revision 122295
150477Speter/*- 22998Swollman * Copyright (c) 1990 The Regents of the University of California. 3221032Srmacklem * All rights reserved. 4122770Simp * 583651Speter * This code is derived from software contributed to Berkeley by 683651Speter * William Jolitz. 7210455Srmacklem * 8203968Smarius * Redistribution and use in source and binary forms, with or without 9131840Sbrian * modification, are permitted provided that the following conditions 10193744Sbz * are met: 1170711Sobrien * 1. Redistributions of source code must retain the above copyright 12151350Syar * notice, this list of conditions and the following disclaimer. 13151350Syar * 2. Redistributions in binary form must reproduce the above copyright 14151350Syar * notice, this list of conditions and the following disclaimer in the 15155823Syar * documentation and/or other materials provided with the distribution. 16151350Syar * 3. All advertising materials mentioning features or use of this software 17134748Sru * must display the following acknowledgement: 1883651Speter * This product includes software developed by the University of 1937462Sbde * California, Berkeley and its contributors. 2032357Seivind * 4. Neither the name of the University nor the names of its contributors 2132357Seivind * may be used to endorse or promote products derived from this software 22100134Salfred * without specific prior written permission. 23100134Salfred * 24100134Salfred * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25100134Salfred * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26155823Syar * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27155823Syar * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28155823Syar * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29155823Syar * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30151350Syar * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31155823Syar * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32155823Syar * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33155823Syar * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34155823Syar * SUCH DAMAGE. 35155823Syar * 36155823Syar * from: @(#)npx.h 5.3 (Berkeley) 1/18/91 37155823Syar * $FreeBSD: head/sys/amd64/include/fpu.h 122295 2003-11-08 04:37:54Z peter $ 38155823Syar */ 39100134Salfred 40155823Syar/* 41155823Syar * Floating Point Data Structures and Constants 42155823Syar * W. Jolitz 1/90 43155823Syar */ 4460966Speter 45#ifndef _MACHINE_FPU_H_ 46#define _MACHINE_FPU_H_ 47 48/* Contents of each x87 floating point accumulator */ 49struct fpacc87 { 50 u_char fp_bytes[10]; 51}; 52 53/* Contents of each SSE extended accumulator */ 54struct xmmacc { 55 u_char xmm_bytes[16]; 56}; 57 58struct envxmm { 59 u_int16_t en_cw; /* control word (16bits) */ 60 u_int16_t en_sw; /* status word (16bits) */ 61 u_int8_t en_tw; /* tag word (8bits) */ 62 u_int8_t en_zero; 63 u_int16_t en_opcode; /* opcode last executed (11 bits ) */ 64 u_int64_t en_rip; /* floating point instruction pointer */ 65 u_int64_t en_rdp; /* floating operand pointer */ 66 u_int32_t en_mxcsr; /* SSE sontorol/status register */ 67 u_int32_t en_mxcsr_mask; /* valid bits in mxcsr */ 68}; 69 70struct savefpu { 71 struct envxmm sv_env; 72 struct { 73 struct fpacc87 fp_acc; 74 u_char fp_pad[6]; /* padding */ 75 } sv_fp[8]; 76 struct xmmacc sv_xmm[16]; 77 u_char sv_pad[96]; 78} __aligned(16); 79 80/* 81 * The hardware default control word for i387's and later coprocessors is 82 * 0x37F, giving: 83 * 84 * round to nearest 85 * 64-bit precision 86 * all exceptions masked. 87 * 88 * FreeBSD/i386 uses 53 bit precision for things like fadd/fsub/fsqrt etc 89 * because of the difference between memory and fpu register stack arguments. 90 * If its using an intermediate fpu register, it has 80/64 bits to work 91 * with. If it uses memory, it has 64/53 bits to work with. However, 92 * gcc is aware of this and goes to a fair bit of trouble to make the 93 * best use of it. 94 * 95 * This is mostly academic for AMD64, because the ABI prefers the use 96 * SSE2 based math. For FreeBSD/amd64, we go with the default settings. 97 */ 98#define __INITIAL_FPUCW__ 0x037F 99#define __INITIAL_MXCSR__ 0x1F80 100#define __INITIAL_MXCSR_MASK__ 0xFFBF 101 102#ifdef _KERNEL 103int fpudna(void); 104void fpudrop(void); 105void fpuexit(struct thread *td); 106int fpuformat(void); 107int fpugetregs(struct thread *td, struct savefpu *addr); 108void fpuinit(void); 109void fpusave(struct savefpu *addr); 110void fpusetregs(struct thread *td, struct savefpu *addr); 111int fputrap(void); 112#endif 113 114#endif /* !_MACHINE_FPU_H_ */ 115