arch/arm/nwfpe/fpa11_cpdo.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3     NetWinder Floating Point Emulator
   4     (c) Rebel.COM, 1998,1999
   5     (c) Philip Blundell, 2001
   6
   7     Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
   8
   9 */
  10
  11 #include "fpa11.h"
  12 #include "fpopcode.h"
  13
  14 unsigned int SingleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd);
  15 unsigned int DoubleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd);
  16 unsigned int ExtendedCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd);
  17
  18 unsigned int EmulateCPDO(const unsigned int opcode)
  19 {
  20         FPA11 *fpa11 = GET_FPA11();
  21         FPREG *rFd;
  22         unsigned int nType, nDest, nRc;
  23         struct roundingData roundData;
  24
  25         /* Get the destination size.  If not valid let Linux perform
  26            an invalid instruction trap. */
  27         nDest = getDestinationSize(opcode);
  28         if (typeNone == nDest)
  29                 return 0;
  30
  31         roundData.mode = SetRoundingMode(opcode);
  32         roundData.precision = SetRoundingPrecision(opcode);
  33         roundData.exception = 0;
  34
  35         /* Compare the size of the operands in Fn and Fm.
  36            Choose the largest size and perform operations in that size,
  37            in order to make use of all the precision of the operands.
  38            If Fm is a constant, we just grab a constant of a size
  39            matching the size of the operand in Fn. */
  40         if (MONADIC_INSTRUCTION(opcode))
  41                 nType = nDest;
  42         else
  43                 nType = fpa11->fType[getFn(opcode)];
  44
  45         if (!CONSTANT_FM(opcode)) {
  46                 register unsigned int Fm = getFm(opcode);
  47                 if (nType < fpa11->fType[Fm]) {
  48                         nType = fpa11->fType[Fm];
  49                 }
  50         }
  51
  52         rFd = &fpa11->fpreg[getFd(opcode)];
  53
  54         switch (nType) {
  55         case typeSingle:
  56                 nRc = SingleCPDO(&roundData, opcode, rFd);
  57                 break;
  58         case typeDouble:
  59                 nRc = DoubleCPDO(&roundData, opcode, rFd);
  60                 break;
  61 #ifdef CONFIG_FPE_NWFPE_XP
  62         case typeExtended:
  63                 nRc = ExtendedCPDO(&roundData, opcode, rFd);
  64                 break;
  65 #endif
  66         default:
  67                 nRc = 0;
  68         }
  69
  70         /* The CPDO functions used to always set the destination type
  71            to be the same as their working size. */
  72
  73         if (nRc != 0) {
  74                 /* If the operation succeeded, check to see if the result in the
  75                    destination register is the correct size.  If not force it
  76                    to be. */
  77
  78                 fpa11->fType[getFd(opcode)] = nDest;
  79
  80 #ifdef CONFIG_FPE_NWFPE_XP
  81                 if (nDest != nType) {
  82                         switch (nDest) {
  83                         case typeSingle:
  84                                 {
  85                                         if (typeDouble == nType)
  86                                                 rFd->fSingle = float64_to_float32(&roundData, rFd->fDouble);
  87                                         else
  88                                                 rFd->fSingle = floatx80_to_float32(&roundData, rFd->fExtended);
  89                                 }
  90                                 break;
  91
  92                         case typeDouble:
  93                                 {
  94                                         if (typeSingle == nType)
  95                                                 rFd->fDouble = float32_to_float64(rFd->fSingle);
  96                                         else
  97                                                 rFd->fDouble = floatx80_to_float64(&roundData, rFd->fExtended);
  98                                 }
  99                                 break;
 100
 101                         case typeExtended:
 102                                 {
 103                                         if (typeSingle == nType)
 104                                                 rFd->fExtended = float32_to_floatx80(rFd->fSingle);
 105                                         else
 106                                                 rFd->fExtended = float64_to_floatx80(rFd->fDouble);
 107                                 }
 108                                 break;
 109                         }
 110                 }
 111 #else
 112                 if (nDest != nType) {
 113                         if (nDest == typeSingle)
 114                                 rFd->fSingle = float64_to_float32(&roundData, rFd->fDouble);
 115                         else
 116                                 rFd->fDouble = float32_to_float64(rFd->fSingle);
 117                 }
 118 #endif
 119         }
 120
 121         if (roundData.exception)
 122                 float_raise(roundData.exception);
 123
 124         return nRc;
 125 }