arch/arm/nwfpe/double_cpdo.c

   1 /*
   2     NetWinder Floating Point Emulator
   3     (c) Rebel.COM, 1998,1999
   4
   5     Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program; if not, write to the Free Software
  19     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "fpa11.h"
  23 #include "softfloat.h"
  24 #include "fpopcode.h"
  25
  26 union float64_components {
  27         float64 f64;
  28         unsigned int i[2];
  29 };
  30
  31 float64 float64_exp(float64 Fm);
  32 float64 float64_ln(float64 Fm);
  33 float64 float64_sin(float64 rFm);
  34 float64 float64_cos(float64 rFm);
  35 float64 float64_arcsin(float64 rFm);
  36 float64 float64_arctan(float64 rFm);
  37 float64 float64_log(float64 rFm);
  38 float64 float64_tan(float64 rFm);
  39 float64 float64_arccos(float64 rFm);
  40 float64 float64_pow(float64 rFn, float64 rFm);
  41 float64 float64_pol(float64 rFn, float64 rFm);
  42
  43 static float64 float64_rsf(float64 rFn, float64 rFm)
  44 {
  45         return float64_sub(rFm, rFn);
  46 }
  47
  48 static float64 float64_rdv(float64 rFn, float64 rFm)
  49 {
  50         return float64_div(rFm, rFn);
  51 }
  52
  53 static float64 (*const dyadic_double[16])(float64 rFn, float64 rFm) = {
  54         [ADF_CODE >> 20] = float64_add,
  55         [MUF_CODE >> 20] = float64_mul,
  56         [SUF_CODE >> 20] = float64_sub,
  57         [RSF_CODE >> 20] = float64_rsf,
  58         [DVF_CODE >> 20] = float64_div,
  59         [RDF_CODE >> 20] = float64_rdv,
  60         [RMF_CODE >> 20] = float64_rem,
  61
  62         /* strictly, these opcodes should not be implemented */
  63         [FML_CODE >> 20] = float64_mul,
  64         [FDV_CODE >> 20] = float64_div,
  65         [FRD_CODE >> 20] = float64_rdv,
  66 };
  67
  68 static float64 float64_mvf(float64 rFm)
  69 {
  70         return rFm;
  71 }
  72
  73 static float64 float64_mnf(float64 rFm)
  74 {
  75         union float64_components u;
  76
  77         u.f64 = rFm;
  78         u.i[1] ^= 0x80000000;
  79
  80         return u.f64;
  81 }
  82
  83 static float64 float64_abs(float64 rFm)
  84 {
  85         union float64_components u;
  86
  87         u.f64 = rFm;
  88         u.i[1] &= 0x7fffffff;
  89
  90         return u.f64;
  91 }
  92
  93 static float64 (*const monadic_double[16])(float64 rFm) = {
  94         [MVF_CODE >> 20] = float64_mvf,
  95         [MNF_CODE >> 20] = float64_mnf,
  96         [ABS_CODE >> 20] = float64_abs,
  97         [RND_CODE >> 20] = float64_round_to_int,
  98         [URD_CODE >> 20] = float64_round_to_int,
  99         [SQT_CODE >> 20] = float64_sqrt,
 100         [NRM_CODE >> 20] = float64_mvf,
 101 };
 102
 103 unsigned int DoubleCPDO(const unsigned int opcode, FPREG * rFd)
 104 {
 105         FPA11 *fpa11 = GET_FPA11();
 106         float64 rFm;
 107         unsigned int Fm, opc_mask_shift;
 108
 109         Fm = getFm(opcode);
 110         if (CONSTANT_FM(opcode)) {
 111                 rFm = getDoubleConstant(Fm);
 112         } else {
 113                 switch (fpa11->fType[Fm]) {
 114                 case typeSingle:
 115                         rFm = float32_to_float64(fpa11->fpreg[Fm].fSingle);
 116                         break;
 117
 118                 case typeDouble:
 119                         rFm = fpa11->fpreg[Fm].fDouble;
 120                         break;
 121
 122                 default:
 123                         return 0;
 124                 }
 125         }
 126
 127         opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
 128         if (!MONADIC_INSTRUCTION(opcode)) {
 129                 unsigned int Fn = getFn(opcode);
 130                 float64 rFn;
 131
 132                 switch (fpa11->fType[Fn]) {
 133                 case typeSingle:
 134                         rFn = float32_to_float64(fpa11->fpreg[Fn].fSingle);
 135                         break;
 136
 137                 case typeDouble:
 138                         rFn = fpa11->fpreg[Fn].fDouble;
 139                         break;
 140
 141                 default:
 142                         return 0;
 143                 }
 144
 145                 if (dyadic_double[opc_mask_shift]) {
 146                         rFd->fDouble = dyadic_double[opc_mask_shift](rFn, rFm);
 147                 } else {
 148                         return 0;
 149                 }
 150         } else {
 151                 if (monadic_double[opc_mask_shift]) {
 152                         rFd->fDouble = monadic_double[opc_mask_shift](rFm);
 153                 } else {
 154                         return 0;
 155                 }
 156         }
 157
 158         return 1;
 159 }