linux/arch/arm/nwfpe/single_cpdo.c
Richard Purdie f148af2593 [PATCH] ARM: 2837/2: Re: ARM: Make NWFPE preempt safe
Patch from Richard Purdie

NWFPE used global variables which meant it wasn't safe for use with
preemptive kernels. This patch removes them and communicates the
information between functions in a preempt safe manner. Generation
of some exceptions was broken and this has also been corrected.
Tests with glibc's maths test suite show no change in the results
before/after this patch.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-03 19:49:17 +01:00

124 lines
3.5 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 "softfloat.h"
#include "fpopcode.h"
float32 float32_exp(float32 Fm);
float32 float32_ln(float32 Fm);
float32 float32_sin(float32 rFm);
float32 float32_cos(float32 rFm);
float32 float32_arcsin(float32 rFm);
float32 float32_arctan(float32 rFm);
float32 float32_log(float32 rFm);
float32 float32_tan(float32 rFm);
float32 float32_arccos(float32 rFm);
float32 float32_pow(float32 rFn, float32 rFm);
float32 float32_pol(float32 rFn, float32 rFm);
static float32 float32_rsf(struct roundingData *roundData, float32 rFn, float32 rFm)
{
return float32_sub(roundData, rFm, rFn);
}
static float32 float32_rdv(struct roundingData *roundData, float32 rFn, float32 rFm)
{
return float32_div(roundData, rFm, rFn);
}
static float32 (*const dyadic_single[16])(struct roundingData *, float32 rFn, float32 rFm) = {
[ADF_CODE >> 20] = float32_add,
[MUF_CODE >> 20] = float32_mul,
[SUF_CODE >> 20] = float32_sub,
[RSF_CODE >> 20] = float32_rsf,
[DVF_CODE >> 20] = float32_div,
[RDF_CODE >> 20] = float32_rdv,
[RMF_CODE >> 20] = float32_rem,
[FML_CODE >> 20] = float32_mul,
[FDV_CODE >> 20] = float32_div,
[FRD_CODE >> 20] = float32_rdv,
};
static float32 float32_mvf(struct roundingData *roundData, float32 rFm)
{
return rFm;
}
static float32 float32_mnf(struct roundingData *roundData, float32 rFm)
{
return rFm ^ 0x80000000;
}
static float32 float32_abs(struct roundingData *roundData, float32 rFm)
{
return rFm & 0x7fffffff;
}
static float32 (*const monadic_single[16])(struct roundingData*, float32 rFm) = {
[MVF_CODE >> 20] = float32_mvf,
[MNF_CODE >> 20] = float32_mnf,
[ABS_CODE >> 20] = float32_abs,
[RND_CODE >> 20] = float32_round_to_int,
[URD_CODE >> 20] = float32_round_to_int,
[SQT_CODE >> 20] = float32_sqrt,
[NRM_CODE >> 20] = float32_mvf,
};
unsigned int SingleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd)
{
FPA11 *fpa11 = GET_FPA11();
float32 rFm;
unsigned int Fm, opc_mask_shift;
Fm = getFm(opcode);
if (CONSTANT_FM(opcode)) {
rFm = getSingleConstant(Fm);
} else if (fpa11->fType[Fm] == typeSingle) {
rFm = fpa11->fpreg[Fm].fSingle;
} else {
return 0;
}
opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
if (!MONADIC_INSTRUCTION(opcode)) {
unsigned int Fn = getFn(opcode);
float32 rFn;
if (fpa11->fType[Fn] == typeSingle &&
dyadic_single[opc_mask_shift]) {
rFn = fpa11->fpreg[Fn].fSingle;
rFd->fSingle = dyadic_single[opc_mask_shift](roundData, rFn, rFm);
} else {
return 0;
}
} else {
if (monadic_single[opc_mask_shift]) {
rFd->fSingle = monadic_single[opc_mask_shift](roundData, rFm);
} else {
return 0;
}
}
return 1;
}