linux-user/arm/nwfpe/fpopcode.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, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "fpa11.h"
  22 #include "softfloat.h"
  23 #include "fpopcode.h"
  24 #include "fpsr.h"
  25 //#include "fpmodule.h"
  26 //#include "fpmodule.inl"
  27
  28 const floatx80 floatx80Constant[] = {
  29   { 0x0000000000000000ULL, 0x0000},     /* extended 0.0 */
  30   { 0x8000000000000000ULL, 0x3fff},     /* extended 1.0 */
  31   { 0x8000000000000000ULL, 0x4000},     /* extended 2.0 */
  32   { 0xc000000000000000ULL, 0x4000},     /* extended 3.0 */
  33   { 0x8000000000000000ULL, 0x4001},     /* extended 4.0 */
  34   { 0xa000000000000000ULL, 0x4001},     /* extended 5.0 */
  35   { 0x8000000000000000ULL, 0x3ffe},     /* extended 0.5 */
  36   { 0xa000000000000000ULL, 0x4002}      /* extended 10.0 */
  37 };
  38
  39 const float64 float64Constant[] = {
  40   const_float64(0x0000000000000000ULL),         /* double 0.0 */
  41   const_float64(0x3ff0000000000000ULL),         /* double 1.0 */
  42   const_float64(0x4000000000000000ULL),         /* double 2.0 */
  43   const_float64(0x4008000000000000ULL),         /* double 3.0 */
  44   const_float64(0x4010000000000000ULL),         /* double 4.0 */
  45   const_float64(0x4014000000000000ULL),         /* double 5.0 */
  46   const_float64(0x3fe0000000000000ULL),         /* double 0.5 */
  47   const_float64(0x4024000000000000ULL)                  /* double 10.0 */
  48 };
  49
  50 const float32 float32Constant[] = {
  51   const_float32(0x00000000),                            /* single 0.0 */
  52   const_float32(0x3f800000),                            /* single 1.0 */
  53   const_float32(0x40000000),                            /* single 2.0 */
  54   const_float32(0x40400000),                            /* single 3.0 */
  55   const_float32(0x40800000),                            /* single 4.0 */
  56   const_float32(0x40a00000),                            /* single 5.0 */
  57   const_float32(0x3f000000),                            /* single 0.5 */
  58   const_float32(0x41200000)                             /* single 10.0 */
  59 };
  60
  61 unsigned int getRegisterCount(const unsigned int opcode)
  62 {
  63   unsigned int nRc;
  64
  65   switch (opcode & MASK_REGISTER_COUNT)
  66   {
  67     case 0x00000000: nRc = 4; break;
  68     case 0x00008000: nRc = 1; break;
  69     case 0x00400000: nRc = 2; break;
  70     case 0x00408000: nRc = 3; break;
  71     default: nRc = 0;
  72   }
  73
  74   return(nRc);
  75 }
  76
  77 unsigned int getDestinationSize(const unsigned int opcode)
  78 {
  79   unsigned int nRc;
  80
  81   switch (opcode & MASK_DESTINATION_SIZE)
  82   {
  83     case 0x00000000: nRc = typeSingle; break;
  84     case 0x00000080: nRc = typeDouble; break;
  85     case 0x00080000: nRc = typeExtended; break;
  86     default: nRc = typeNone;
  87   }
  88
  89   return(nRc);
  90 }
  91
  92 /* condition code lookup table
  93  index into the table is test code: EQ, NE, ... LT, GT, AL, NV
  94  bit position in short is condition code: NZCV */
  95 static const unsigned short aCC[16] = {
  96     0xF0F0, // EQ == Z set
  97     0x0F0F, // NE
  98     0xCCCC, // CS == C set
  99     0x3333, // CC
 100     0xFF00, // MI == N set
 101     0x00FF, // PL
 102     0xAAAA, // VS == V set
 103     0x5555, // VC
 104     0x0C0C, // HI == C set && Z clear
 105     0xF3F3, // LS == C clear || Z set
 106     0xAA55, // GE == (N==V)
 107     0x55AA, // LT == (N!=V)
 108     0x0A05, // GT == (!Z && (N==V))
 109     0xF5FA, // LE == (Z || (N!=V))
 110     0xFFFF, // AL always
 111     0 // NV
 112 };