1 /*- 2 * Copyright (c) 2013 The NetBSD Foundation, Inc. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to The NetBSD Foundation 6 * by Matt Thomas of 3am Software Foundry. 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 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __RCSID("$NetBSD: fenv.c,v 1.3 2013/05/01 04:04:54 matt Exp $"); 32 33 #include <sys/types.h> 34 #include <assert.h> 35 #include <fenv.h> 36 #include <string.h> 37 #include <unistd.h> 38 #include <inttypes.h> 39 40 #ifdef __SOFTFP__ 41 #include <ieeefp.h> 42 #include <sys/signal.h> 43 #include <sys/siginfo.h> 44 #else 45 #include <arm/armreg.h> 46 #endif 47 48 #include <arm/vfpreg.h> 49 50 const fenv_t __fe_dfl_env = VFP_FPSCR_FZ|VFP_FPSCR_DN|VFP_FPSCR_RN; 51 52 /* 53 * The feclearexcept() function shall attempt to clear the supported 54 * floating-point exceptions represented by excepts. 55 */ 56 int 57 feclearexcept(int excepts) 58 { 59 #ifndef lint 60 _DIAGASSERT((except & ~FE_EXCEPT_ALL) == 0); 61 #endif 62 #ifdef __SOFTFP__ 63 fpsetsticky(fpgetsticky() & ~excepts); 64 return 0; 65 #else 66 int tmp = armreg_fpscr_read() & ~__SHIFTIN(excepts, VFP_FPSCR_CSUM); 67 armreg_fpscr_write(tmp); 68 return 0; 69 #endif 70 } 71 72 /* 73 * The fegetexceptflag() function shall attempt to store an 74 * implementation-defined representation of the states of the floating-point 75 * status flags indicated by the argument excepts in the object pointed to by 76 * the argument flagp. 77 */ 78 int 79 fegetexceptflag(fexcept_t *flagp, int excepts) 80 { 81 _DIAGASSERT((except & ~FE_EXCEPT_ALL) == 0); 82 #ifdef __SOFTFP__ 83 *flagp = fpgetsticky() & excepts; 84 #else 85 *flagp = __SHIFTOUT(armreg_fpscr_read(), VFP_FPSCR_CSUM) & excepts; 86 #endif 87 return 0; 88 } 89 90 /* 91 * The feraiseexcept() function shall attempt to raise the supported 92 * floating-point exceptions represented by the argument excepts. The order 93 * in which these floating-point exceptions are raised is unspecified. 94 */ 95 int 96 feraiseexcept(int excepts) 97 { 98 #ifndef lint 99 _DIAGASSERT((except & ~FE_EXCEPT_ALL) == 0); 100 #endif 101 #if !defined(__minix) /* LSC: No sigqueueinfo on Minix. */ 102 #ifdef __SOFTFP__ 103 excepts &= fpgetsticky(); 104 105 if (excepts) { 106 siginfo_t info; 107 memset(&info, 0, sizeof info); 108 info.si_signo = SIGFPE; 109 info.si_pid = getpid(); 110 info.si_uid = geteuid(); 111 if (excepts & FE_UNDERFLOW) 112 info.si_code = FPE_FLTUND; 113 else if (excepts & FE_OVERFLOW) 114 info.si_code = FPE_FLTOVF; 115 else if (excepts & FE_DIVBYZERO) 116 info.si_code = FPE_FLTDIV; 117 else if (excepts & FE_INVALID) 118 info.si_code = FPE_FLTINV; 119 else if (excepts & FE_INEXACT) 120 info.si_code = FPE_FLTRES; 121 sigqueueinfo(getpid(), &info); 122 } 123 #else 124 int fpscr = armreg_fpscr_read(); 125 fpscr = (fpscr & ~VFP_FPSCR_ESUM) | __SHIFTIN(excepts, VFP_FPSCR_ESUM); 126 armreg_fpscr_write(fpscr); 127 #endif 128 #endif /* !defined(__minix) */ 129 return 0; 130 } 131 132 /* 133 * The fesetexceptflag() function shall attempt to set the floating-point 134 * status flags indicated by the argument excepts to the states stored in the 135 * object pointed to by flagp. The value pointed to by flagp shall have been 136 * set by a previous call to fegetexceptflag() whose second argument 137 * represented at least those floating-point exceptions represented by the 138 * argument excepts. This function does not raise floating-point exceptions, 139 * but only sets the state of the flags. 140 */ 141 int 142 fesetexceptflag(const fexcept_t *flagp, int excepts) 143 { 144 #ifndef lint 145 _DIAGASSERT((except & ~FE_EXCEPT_ALL) == 0); 146 #endif 147 #ifdef __SOFTFP__ 148 fpsetsticky((fpgetsticky() & ~excepts) | (excepts & *flagp)); 149 #else 150 int fpscr = armreg_fpscr_read(); 151 fpscr &= ~__SHIFTIN(excepts, VFP_FPSCR_CSUM); 152 fpscr |= __SHIFTIN((*flagp & excepts), VFP_FPSCR_CSUM); 153 armreg_fpscr_write(fpscr); 154 #endif 155 return 0; 156 } 157 158 /* 159 * The fetestexcept() function shall determine which of a specified subset of 160 * the floating-point exception flags are currently set. The excepts argument 161 * specifies the floating-point status flags to be queried. 162 */ 163 int 164 fetestexcept(int excepts) 165 { 166 _DIAGASSERT((except & ~FE_EXCEPT_ALL) == 0); 167 #ifdef __SOFTFP__ 168 return fpgetsticky() & excepts; 169 #else 170 return __SHIFTOUT(armreg_fpscr_read(), VFP_FPSCR_CSUM) & excepts; 171 #endif 172 } 173 174 /* 175 * The fegetround() function shall get the current rounding direction. 176 */ 177 int 178 fegetround(void) 179 { 180 #ifdef __SOFTFP__ 181 return fpgetround(); 182 #else 183 return __SHIFTOUT(armreg_fpscr_read(), VFP_FPSCR_RMODE); 184 #endif 185 } 186 187 /* 188 * The fesetround() function shall establish the rounding direction represented 189 * by its argument round. If the argument is not equal to the value of a 190 * rounding direction macro, the rounding direction is not changed. 191 */ 192 int 193 fesetround(int round) 194 { 195 #ifndef lint 196 _DIAGASSERT(!(round & ~__SHIFTOUT(VFP_FPSCR_RMODE, VFP_FPSCR_RMODE))); 197 #endif 198 #ifdef __SOFTFP__ 199 (void)fpsetround(round); 200 #else 201 int fpscr = armreg_fpscr_read() & ~VFP_FPSCR_RMODE; 202 fpscr |= __SHIFTIN(round, VFP_FPSCR_RMODE); 203 armreg_fpscr_write(fpscr); 204 #endif 205 return 0; 206 } 207 208 /* 209 * The fegetenv() function shall attempt to store the current floating-point 210 * environment in the object pointed to by envp. 211 */ 212 int 213 fegetenv(fenv_t *envp) 214 { 215 #ifdef __SOFTFP__ 216 *envp = __SHIFTIN(fpgetround(), VFP_FPSCR_RMODE) 217 | __SHIFTIN(fpgetmask(), VFP_FPSCR_ESUM) 218 | __SHIFTIN(fpgetsticky(), VFP_FPSCR_CSUM); 219 #else 220 *envp = armreg_fpscr_read(); 221 #endif 222 return 0; 223 } 224 225 /* 226 * The feholdexcept() function shall save the current floating-point 227 * environment in the object pointed to by envp, clear the floating-point 228 * status flags, and then install a non-stop (continue on floating-point 229 * exceptions) mode, if available, for all floating-point exceptions. 230 */ 231 int 232 feholdexcept(fenv_t *envp) 233 { 234 #ifdef __SOFTFP__ 235 *envp = __SHIFTIN(fpgetround(), VFP_FPSCR_RMODE) 236 | __SHIFTIN(fpgetmask(), VFP_FPSCR_ESUM) 237 | __SHIFTIN(fpgetsticky(), VFP_FPSCR_CSUM); 238 fpsetmask(0); 239 fpsetsticky(0); 240 #else 241 *envp = armreg_fpscr_read(); 242 armreg_fpscr_write((*envp) & ~(VFP_FPSCR_ESUM|VFP_FPSCR_CSUM)); 243 #endif 244 return 0; 245 } 246 247 /* 248 * The fesetenv() function shall attempt to establish the floating-point 249 * environment represented by the object pointed to by envp. The fesetenv() 250 * function does not raise floating-point exceptions, but only installs the 251 * state of the floating-point status flags represented through its argument. 252 */ 253 int 254 fesetenv(const fenv_t *envp) 255 { 256 #ifdef __SOFTFP__ 257 (void)fpsetround(__SHIFTIN(*envp, VFP_FPSCR_RMODE)); 258 (void)fpsetmask(__SHIFTOUT(*envp, VFP_FPSCR_ESUM)); 259 (void)fpsetsticky(__SHIFTOUT(*envp, VFP_FPSCR_CSUM)); 260 #else 261 armreg_fpscr_write(*envp); 262 #endif 263 return 0; 264 } 265 266 /* 267 * The feupdateenv() function shall attempt to save the currently raised 268 * floating-point exceptions in its automatic storage, attempt to install the 269 * floating-point environment represented by the object pointed to by envp, 270 * and then attempt to raise the saved floating-point exceptions. 271 */ 272 int 273 feupdateenv(const fenv_t *envp) 274 { 275 #ifndef lint 276 _DIAGASSERT(envp != NULL); 277 #endif 278 #ifdef __SOFTFP__ 279 (void)fpsetround(__SHIFTIN(*envp, VFP_FPSCR_RMODE)); 280 (void)fpsetmask(fpgetmask() | __SHIFTOUT(*envp, VFP_FPSCR_ESUM)); 281 (void)fpsetsticky(fpgetsticky() | __SHIFTOUT(*envp, VFP_FPSCR_CSUM)); 282 #else 283 int fpscr = armreg_fpscr_read() & ~(VFP_FPSCR_ESUM|VFP_FPSCR_CSUM); 284 fpscr |= *envp; 285 armreg_fpscr_write(fpscr); 286 #endif 287 288 /* Success */ 289 return 0; 290 } 291