1 /* ieee-utils/fp-gnum68k.c 2 * 3 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 2007 Brian Gough 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 3 of the License, or (at 8 * your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 18 */ 19 20 #include <stdio.h> 21 #include <fpu_control.h> 22 #include "gsl_errno.h" 23 #include "gsl_ieee_utils.h" 24 25 int 26 gsl_ieee_set_mode (int precision, int rounding, int exception_mask) 27 { 28 unsigned short mode = 0 ; 29 30 switch (precision) 31 { 32 case GSL_IEEE_SINGLE_PRECISION: 33 mode |= _FPU_SINGLE ; 34 break ; 35 case GSL_IEEE_DOUBLE_PRECISION: 36 mode |= _FPU_DOUBLE ; 37 break ; 38 case GSL_IEEE_EXTENDED_PRECISION: 39 mode |= _FPU_EXTENDED ; 40 break ; 41 default: 42 mode |= _FPU_EXTENDED ; 43 } 44 45 switch (rounding) 46 { 47 case GSL_IEEE_ROUND_TO_NEAREST: 48 mode |= _FPU_RC_NEAREST ; 49 break ; 50 case GSL_IEEE_ROUND_DOWN: 51 mode |= _FPU_RC_DOWN ; 52 break ; 53 case GSL_IEEE_ROUND_UP: 54 mode |= _FPU_RC_UP ; 55 break ; 56 case GSL_IEEE_ROUND_TO_ZERO: 57 mode |= _FPU_RC_ZERO ; 58 break ; 59 default: 60 mode |= _FPU_RC_NEAREST ; 61 } 62 63 /* FIXME: I don't have documentation for the M68K so I'm not sure 64 about the mapping of the exceptions below. Maybe someone who does 65 know could correct this. */ 66 67 if (exception_mask & GSL_IEEE_MASK_INVALID) 68 mode |= _FPU_MASK_OPERR ; 69 70 if (exception_mask & GSL_IEEE_MASK_DENORMALIZED) 71 { 72 /* do nothing */ 73 } 74 else 75 { 76 GSL_ERROR ("the denormalized operand exception has not been implemented for m68k yet. Use 'mask-denormalized' to work around this.", GSL_EUNSUP) ; 77 /*mode |= _FPU_MASK_DM ; ???? */ 78 } 79 80 if (exception_mask & GSL_IEEE_MASK_DIVISION_BY_ZERO) 81 mode |= _FPU_MASK_DZ ; 82 83 if (exception_mask & GSL_IEEE_MASK_OVERFLOW) 84 mode |= _FPU_MASK_OVFL ; 85 86 if (exception_mask & GSL_IEEE_MASK_UNDERFLOW) 87 mode |= _FPU_MASK_UNFL ; 88 89 if (exception_mask & GSL_IEEE_TRAP_INEXACT) 90 { 91 mode &= ~ (_FPU_MASK_INEX1 | _FPU_MASK_INEX2) ; 92 } 93 else 94 { 95 mode |= (_FPU_MASK_INEX1 | _FPU_MASK_INEX2) ; 96 } 97 98 _FPU_SETCW(mode) ; 99 100 return GSL_SUCCESS ; 101 } 102