mirror of https://gitee.com/openkylin/linux.git
138 lines
3.7 KiB
C
138 lines
3.7 KiB
C
/*
|
|
NetWinder Floating Point Emulator
|
|
(c) Rebel.COM, 1998,1999
|
|
(c) Philip Blundell, 2001
|
|
|
|
Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
|
|
#include "fpa11.h"
|
|
#include "fpopcode.h"
|
|
|
|
unsigned int SingleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd);
|
|
unsigned int DoubleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd);
|
|
unsigned int ExtendedCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd);
|
|
|
|
unsigned int EmulateCPDO(const unsigned int opcode)
|
|
{
|
|
FPA11 *fpa11 = GET_FPA11();
|
|
FPREG *rFd;
|
|
unsigned int nType, nDest, nRc;
|
|
struct roundingData roundData;
|
|
|
|
/* Get the destination size. If not valid let Linux perform
|
|
an invalid instruction trap. */
|
|
nDest = getDestinationSize(opcode);
|
|
if (typeNone == nDest)
|
|
return 0;
|
|
|
|
roundData.mode = SetRoundingMode(opcode);
|
|
roundData.precision = SetRoundingPrecision(opcode);
|
|
roundData.exception = 0;
|
|
|
|
/* Compare the size of the operands in Fn and Fm.
|
|
Choose the largest size and perform operations in that size,
|
|
in order to make use of all the precision of the operands.
|
|
If Fm is a constant, we just grab a constant of a size
|
|
matching the size of the operand in Fn. */
|
|
if (MONADIC_INSTRUCTION(opcode))
|
|
nType = nDest;
|
|
else
|
|
nType = fpa11->fType[getFn(opcode)];
|
|
|
|
if (!CONSTANT_FM(opcode)) {
|
|
register unsigned int Fm = getFm(opcode);
|
|
if (nType < fpa11->fType[Fm]) {
|
|
nType = fpa11->fType[Fm];
|
|
}
|
|
}
|
|
|
|
rFd = &fpa11->fpreg[getFd(opcode)];
|
|
|
|
switch (nType) {
|
|
case typeSingle:
|
|
nRc = SingleCPDO(&roundData, opcode, rFd);
|
|
break;
|
|
case typeDouble:
|
|
nRc = DoubleCPDO(&roundData, opcode, rFd);
|
|
break;
|
|
#ifdef CONFIG_FPE_NWFPE_XP
|
|
case typeExtended:
|
|
nRc = ExtendedCPDO(&roundData, opcode, rFd);
|
|
break;
|
|
#endif
|
|
default:
|
|
nRc = 0;
|
|
}
|
|
|
|
/* The CPDO functions used to always set the destination type
|
|
to be the same as their working size. */
|
|
|
|
if (nRc != 0) {
|
|
/* If the operation succeeded, check to see if the result in the
|
|
destination register is the correct size. If not force it
|
|
to be. */
|
|
|
|
fpa11->fType[getFd(opcode)] = nDest;
|
|
|
|
#ifdef CONFIG_FPE_NWFPE_XP
|
|
if (nDest != nType) {
|
|
switch (nDest) {
|
|
case typeSingle:
|
|
{
|
|
if (typeDouble == nType)
|
|
rFd->fSingle = float64_to_float32(&roundData, rFd->fDouble);
|
|
else
|
|
rFd->fSingle = floatx80_to_float32(&roundData, rFd->fExtended);
|
|
}
|
|
break;
|
|
|
|
case typeDouble:
|
|
{
|
|
if (typeSingle == nType)
|
|
rFd->fDouble = float32_to_float64(rFd->fSingle);
|
|
else
|
|
rFd->fDouble = floatx80_to_float64(&roundData, rFd->fExtended);
|
|
}
|
|
break;
|
|
|
|
case typeExtended:
|
|
{
|
|
if (typeSingle == nType)
|
|
rFd->fExtended = float32_to_floatx80(rFd->fSingle);
|
|
else
|
|
rFd->fExtended = float64_to_floatx80(rFd->fDouble);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
#else
|
|
if (nDest != nType) {
|
|
if (nDest == typeSingle)
|
|
rFd->fSingle = float64_to_float32(&roundData, rFd->fDouble);
|
|
else
|
|
rFd->fDouble = float32_to_float64(rFd->fSingle);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if (roundData.exception)
|
|
float_raise(roundData.exception);
|
|
|
|
return nRc;
|
|
}
|