1 /*- 2 * SPDX-License-Identifier: BSD-4-Clause 3 * 4 * Copyright (c) 2003 Peter Wemm. 5 * Copyright (c) 1990 Andrew Moore, Talke Studio 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef _MACHINE_IEEEFP_H_ 38 #define _MACHINE_IEEEFP_H_ 39 40 /* Deprecated historical FPU control interface */ 41 42 #include <x86/x86_ieeefp.h> 43 44 /* 45 * IEEE floating point type, constant and function definitions. 46 * XXX: {FP,SSE}*FLD and {FP,SSE}*OFF are undocumented pollution. 47 */ 48 49 /* 50 * SSE mxcsr register bit-field masks. 51 */ 52 #define SSE_STKY_FLD 0x3f /* exception flags */ 53 #define SSE_DAZ_FLD 0x40 /* Denormals are zero */ 54 #define SSE_MSKS_FLD 0x1f80 /* exception masks field */ 55 #define SSE_RND_FLD 0x6000 /* rounding control */ 56 #define SSE_FZ_FLD 0x8000 /* flush to zero on underflow */ 57 58 /* 59 * SSE mxcsr register bit-field offsets (shift counts). 60 */ 61 #define SSE_STKY_OFF 0 /* exception flags offset */ 62 #define SSE_DAZ_OFF 6 /* DAZ exception mask offset */ 63 #define SSE_MSKS_OFF 7 /* other exception masks offset */ 64 #define SSE_RND_OFF 13 /* rounding control offset */ 65 #define SSE_FZ_OFF 15 /* flush to zero offset */ 66 67 /* 68 * General notes about conflicting SSE vs FP status bits. 69 * This code assumes that software will not fiddle with the control 70 * bits of the SSE and x87 in such a way to get them out of sync and 71 * still expect this to work. Break this at your peril. 72 * Because I based this on the i386 port, the x87 state is used for 73 * the fpget*() functions, and is shadowed into the SSE state for 74 * the fpset*() functions. For dual source fpget*() functions, I 75 * merge the two together. I think. 76 */ 77 78 static __inline fp_rnd_t 79 __fpgetround(void) 80 { 81 unsigned short _cw; 82 83 __fnstcw(&_cw); 84 return ((fp_rnd_t)((_cw & FP_RND_FLD) >> FP_RND_OFF)); 85 } 86 87 static __inline fp_rnd_t 88 __fpsetround(fp_rnd_t _m) 89 { 90 fp_rnd_t _p; 91 unsigned _mxcsr; 92 unsigned short _cw, _newcw; 93 94 __fnstcw(&_cw); 95 _p = (fp_rnd_t)((_cw & FP_RND_FLD) >> FP_RND_OFF); 96 _newcw = _cw & ~FP_RND_FLD; 97 _newcw |= (_m << FP_RND_OFF) & FP_RND_FLD; 98 __fnldcw(_cw, _newcw); 99 __stmxcsr(&_mxcsr); 100 _mxcsr &= ~SSE_RND_FLD; 101 _mxcsr |= (_m << SSE_RND_OFF) & SSE_RND_FLD; 102 __ldmxcsr(&_mxcsr); 103 return (_p); 104 } 105 106 /* 107 * Get or set the rounding precision for x87 arithmetic operations. 108 * There is no equivalent SSE mode or control. 109 */ 110 111 static __inline fp_prec_t 112 __fpgetprec(void) 113 { 114 unsigned short _cw; 115 116 __fnstcw(&_cw); 117 return ((fp_prec_t)((_cw & FP_PRC_FLD) >> FP_PRC_OFF)); 118 } 119 120 static __inline fp_prec_t 121 __fpsetprec(fp_prec_t _m) 122 { 123 fp_prec_t _p; 124 unsigned short _cw, _newcw; 125 126 __fnstcw(&_cw); 127 _p = (fp_prec_t)((_cw & FP_PRC_FLD) >> FP_PRC_OFF); 128 _newcw = _cw & ~FP_PRC_FLD; 129 _newcw |= (_m << FP_PRC_OFF) & FP_PRC_FLD; 130 __fnldcw(_cw, _newcw); 131 return (_p); 132 } 133 134 /* 135 * Get or set the exception mask. 136 * Note that the x87 mask bits are inverted by the API -- a mask bit of 1 137 * means disable for x87 and SSE, but for fp*mask() it means enable. 138 */ 139 140 static __inline fp_except_t 141 __fpgetmask(void) 142 { 143 unsigned short _cw; 144 145 __fnstcw(&_cw); 146 return ((~_cw & FP_MSKS_FLD) >> FP_MSKS_OFF); 147 } 148 149 static __inline fp_except_t 150 __fpsetmask(fp_except_t _m) 151 { 152 fp_except_t _p; 153 unsigned _mxcsr; 154 unsigned short _cw, _newcw; 155 156 __fnstcw(&_cw); 157 _p = (~_cw & FP_MSKS_FLD) >> FP_MSKS_OFF; 158 _newcw = _cw & ~FP_MSKS_FLD; 159 _newcw |= (~_m << FP_MSKS_OFF) & FP_MSKS_FLD; 160 __fnldcw(_cw, _newcw); 161 __stmxcsr(&_mxcsr); 162 /* XXX should we clear non-ieee SSE_DAZ_FLD and SSE_FZ_FLD ? */ 163 _mxcsr &= ~SSE_MSKS_FLD; 164 _mxcsr |= (~_m << SSE_MSKS_OFF) & SSE_MSKS_FLD; 165 __ldmxcsr(&_mxcsr); 166 return (_p); 167 } 168 169 static __inline fp_except_t 170 __fpgetsticky(void) 171 { 172 unsigned _ex, _mxcsr; 173 unsigned short _sw; 174 175 __fnstsw(&_sw); 176 _ex = (_sw & FP_STKY_FLD) >> FP_STKY_OFF; 177 __stmxcsr(&_mxcsr); 178 _ex |= (_mxcsr & SSE_STKY_FLD) >> SSE_STKY_OFF; 179 return ((fp_except_t)_ex); 180 } 181 182 #if !defined(__IEEEFP_NOINLINES__) 183 184 #define fpgetmask() __fpgetmask() 185 #define fpgetprec() __fpgetprec() 186 #define fpgetround() __fpgetround() 187 #define fpgetsticky() __fpgetsticky() 188 #define fpsetmask(m) __fpsetmask(m) 189 #define fpsetprec(m) __fpsetprec(m) 190 #define fpsetround(m) __fpsetround(m) 191 192 #else /* __IEEEFP_NOINLINES__ */ 193 194 /* Augment the userland declarations. */ 195 __BEGIN_DECLS 196 extern fp_rnd_t fpgetround(void); 197 extern fp_rnd_t fpsetround(fp_rnd_t); 198 extern fp_except_t fpgetmask(void); 199 extern fp_except_t fpsetmask(fp_except_t); 200 extern fp_except_t fpgetsticky(void); 201 extern fp_except_t fpsetsticky(fp_except_t); 202 fp_prec_t fpgetprec(void); 203 fp_prec_t fpsetprec(fp_prec_t); 204 __END_DECLS 205 206 #endif /* !__IEEEFP_NOINLINES__ */ 207 208 #endif /* !_MACHINE_IEEEFP_H_ */ 209