/*---------------------------------------------------------------------------+
| reg_ld_str.c |
| |
| All of the functions which transfer data between user memory and FPU_REGs.|
| |
| Copyright (C) 1992,1993,1994 |
| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
| Australia. E-mail billm@vaxc.cc.monash.edu.au |
| |
| |
+---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------+
| Note: |
| The file contains code which accesses user memory. |
| Emulator static data may change when user memory is accessed, due to |
| other processes using the emulator while swapping is in progress. |
+---------------------------------------------------------------------------*/
#include <asm/segment.h>
#include "fpu_system.h"
#include "exception.h"
#include "reg_constant.h"
#include "fpu_emu.h"
#include "control_w.h"
#include "status_w.h"
#define EXTENDED_Ebias 0x3fff
#define EXTENDED_Emin (-0x3ffe) /* smallest valid exponent */
#define DOUBLE_Emax 1023 /* largest valid exponent */
#define DOUBLE_Ebias 1023
#define DOUBLE_Emin (-1022) /* smallest valid exponent */
#define SINGLE_Emax 127 /* largest valid exponent */
#define SINGLE_Ebias 127
#define SINGLE_Emin (-126) /* smallest valid exponent */
static void write_to_extended(FPU_REG *rp, char *d);
FPU_REG FPU_loaded_data;
/* Get a long double from user memory */
int reg_load_extended(void)
{
long double *s = (long double *)FPU_data_address;
unsigned long sigl, sigh, exp;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, s, 10);
/* Use temporary variables here because FPU_loaded data is
static and hence re-entrancy problems can arise */
sigl = get_fs_long((unsigned long *) s);
sigh = get_fs_long(1 + (unsigned long *) s);
exp = get_fs_word(4 + (unsigned short *) s);
RE_ENTRANT_CHECK_ON;
FPU_loaded_data.tag = TW_Valid; /* Default */
FPU_loaded_data.sigl = sigl;
FPU_loaded_data.sigh = sigh;
if (exp & 0x8000)
FPU_loaded_data.sign = SIGN_NEG;
else
FPU_loaded_data.sign = SIGN_POS;
exp &= 0x7fff;
FPU_loaded_data.exp = exp - EXTENDED_Ebias + EXP_BIAS;
/* Assume that optimisation can keep sigl, sigh, and exp in
registers, otherwise it would be more efficient to work
with FPU_loaded_data (which is static) here. */
if ( exp == 0 )
{
if ( !(sigh | sigl) )
{
FPU_loaded_data.tag = TW_Zero;
return 0;
}
/* The number is a de-normal or pseudodenormal. */
if (sigh & 0x80000000)
{
/* Is a pseudodenormal. */
/* Convert it for internal use. */
/* This is non-80486 behaviour because the number
loses its 'denormal' identity. */
FPU_loaded_data.exp++;
return 1;
}
else
{
/* Is a denormal. */
/* Convert it for internal use. */
FPU_loaded_data.exp++;
normalize_nuo(&FPU_loaded_data);
return 0;
}
}
else if ( exp == 0x7fff )
{
if ( !((sigh ^ 0x80000000) | sigl) )
{
/* Matches the bit pattern for Infinity. */
FPU_loaded_data.exp = EXP_Infinity;
FPU_loaded_data.tag = TW_Infinity;
return 0;
}
FPU_loaded_data.exp = EXP_NaN;
FPU_loaded_data.tag = TW_NaN;
if ( !(sigh & 0x80000000) )
{
/* NaNs have the ms bit set to 1. */
/* This is therefore an Unsupported NaN data type. */
/* This is non 80486 behaviour */
/* This should generate an Invalid Operand exception
later, so we convert it to a SNaN */
FPU_loaded_data.sigh = 0x80000000;
FPU_loaded_data.sigl = 0x00000001;
FPU_loaded_data.sign = SIGN_NEG;
return 1;
}
return 0;
}
if ( !(sigh & 0x80000000) )
{
/* Unsupported data type. */
/* Valid numbers have the ms bit set to 1. */
/* Unnormal. */
/* Convert it for internal use. */
/* This is non-80486 behaviour */
/* This should generate an Invalid Operand exception
later, so we convert it to a SNaN */
FPU_loaded_data.sigh = 0x80000000;
FPU_loaded_data.sigl = 0x00000001;
FPU_loaded_data.sign = SIGN_NEG;
FPU_loaded_data.exp = EXP_NaN;
FPU_loaded_data.tag = TW_NaN;
return 1;
}
return 0;
}
/* Get a double from user memory */
int reg_load_double(void)
{
double *dfloat = (double *)FPU_data_address;
int exp;
unsigned m64, l64;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, dfloat, 8);
m64 = get_fs_long(1 + (unsigned long *) dfloat);
l64 = get_fs_long((unsigned long *) dfloat);
RE_ENTRANT_CHECK_ON;
if (m64 & 0x80000000)
FPU_loaded_data.sign = SIGN_NEG;
else
FPU_loaded_data.sign = SIGN_POS;
exp = ((m64 & 0x7ff00000) >> 20) - DOUBLE_Ebias;
m64 &= 0xfffff;
if (exp > DOUBLE_Emax)
{
/* Infinity or NaN */
if ((m64 == 0) && (l64 == 0))
{
/* +- infinity */
FPU_loaded_data.sigh = 0x80000000;
FPU_loaded_data.sigl = 0x00000000;
FPU_loaded_data.exp = EXP_Infinity;
FPU_loaded_data.tag = TW_Infinity;
return 0;
}
else
{
/* Must be a signaling or quiet NaN */
FPU_loaded_data.exp = EXP_NaN;
FPU_loaded_data.tag = TW_NaN;
FPU_loaded_data.sigh = (m64 << 11) | 0x80000000;
FPU_loaded_data.sigh |= l64 >> 21;
FPU_loaded_data.sigl = l64 << 11;
return 0; /* The calling function must look for NaNs */
}
}
else if ( exp < DOUBLE_Emin )
{
/* Zero or de-normal */
if ((m64 == 0) && (l64 == 0))
{
/* Zero */
int c = FPU_loaded_data.sign;
reg_move(&CONST_Z, &FPU_loaded_data);
FPU_loaded_data.sign = c;
return 0;
}
else
{
/* De-normal */
FPU_loaded_data.exp = DOUBLE_Emin + EXP_BIAS;
FPU_loaded_data.tag = TW_Valid;
FPU_loaded_data.sigh = m64 << 11;
FPU_loaded_data.sigh |= l64 >> 21;
FPU_loaded_data.sigl = l64 << 11;
normalize_nuo(&FPU_loaded_data);
return denormal_operand();
}
}
else
{
FPU_loaded_data.exp = exp + EXP_BIAS;
FPU_loaded_data.tag = TW_Valid;
FPU_loaded_data.sigh = (m64 << 11) | 0x80000000;
FPU_loaded_data.sigh |= l64 >> 21;
FPU_loaded_data.sigl = l64 << 11;
return 0;
}
}
/* Get a float from user memory */
int reg_load_single(void)
{
float *single = (float *)FPU_data_address;
unsigned m32;
int exp;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, single, 4);
m32 = get_fs_long((unsigned long *) single);
RE_ENTRANT_CHECK_ON;
if (m32 & 0x80000000)
FPU_loaded_data.sign = SIGN_NEG;
else
FPU_loaded_data.sign = SIGN_POS;
if (!(m32 & 0x7fffffff))
{
/* Zero */
int c = FPU_loaded_data.sign;
reg_move(&CONST_Z, &FPU_loaded_data);
FPU_loaded_data.sign = c;
return 0;
}
exp = ((m32 & 0x7f800000) >> 23) - SINGLE_Ebias;
m32 = (m32 & 0x7fffff) << 8;
if ( exp < SINGLE_Emin )
{
/* De-normals */
FPU_loaded_data.exp = SINGLE_Emin + EXP_BIAS;
FPU_loaded_data.tag = TW_Valid;
FPU_loaded_data.sigh = m32;
FPU_loaded_data.sigl = 0;
normalize_nuo(&FPU_loaded_data);
return denormal_operand();
}
else if ( exp > SINGLE_Emax )
{
/* Infinity or NaN */
if ( m32 == 0 )
{
/* +- infinity */
FPU_loaded_data.sigh = 0x80000000;
FPU_loaded_data.sigl = 0x00000000;
FPU_loaded_data.exp = EXP_Infinity;
FPU_loaded_data.tag = TW_Infinity;
return 0;
}
else
{
/* Must be a signaling or quiet NaN */
FPU_loaded_data.exp = EXP_NaN;
FPU_loaded_data.tag = TW_NaN;
FPU_loaded_data.sigh = m32 | 0x80000000;
FPU_loaded_data.sigl = 0;
return 0; /* The calling function must look for NaNs */
}
}
else
{
FPU_loaded_data.exp = exp + EXP_BIAS;
FPU_loaded_data.sigh = m32 | 0x80000000;
FPU_loaded_data.sigl = 0;
FPU_loaded_data.tag = TW_Valid;
return 0;
}
}
/* Get a long long from user memory */
void reg_load_int64(void)
{
long long *_s = (long long *)FPU_data_address;
int e;
long long s;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, _s, 8);
((unsigned long *)&s)[0] = get_fs_long((unsigned long *) _s);
((unsigned long *)&s)[1] = get_fs_long(1 + (unsigned long *) _s);
RE_ENTRANT_CHECK_ON;
if (s == 0)
{ reg_move(&CONST_Z, &FPU_loaded_data); return; }
if (s > 0)
FPU_loaded_data.sign = SIGN_POS;
else
{
s = -s;
FPU_loaded_data.sign = SIGN_NEG;
}
e = EXP_BIAS + 63;
significand(&FPU_loaded_data) = s;
FPU_loaded_data.exp = e;
FPU_loaded_data.tag = TW_Valid;
normalize_nuo(&FPU_loaded_data);
}
/* Get a long from user memory */
void reg_load_int32(void)
{
long *_s = (long *)FPU_data_address;
long s;
int e;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, _s, 4);
s = (long)get_fs_long((unsigned long *) _s);
RE_ENTRANT_CHECK_ON;
if (s == 0)
{ reg_move(&CONST_Z, &FPU_loaded_data); return; }
if (s > 0)
FPU_loaded_data.sign = SIGN_POS;
else
{
s = -s;
FPU_loaded_data.sign = SIGN_NEG;
}
e = EXP_BIAS + 31;
FPU_loaded_data.sigh = s;
FPU_loaded_data.sigl = 0;
FPU_loaded_data.exp = e;
FPU_loaded_data.tag = TW_Valid;
normalize_nuo(&FPU_loaded_data);
}
/* Get a short from user memory */
void reg_load_int16(void)
{
short *_s = (short *)FPU_data_address;
int s, e;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, _s, 2);
/* Cast as short to get the sign extended. */
s = (short)get_fs_word((unsigned short *) _s);
RE_ENTRANT_CHECK_ON;
if (s == 0)
{ reg_move(&CONST_Z, &FPU_loaded_data); return; }
if (s > 0)
FPU_loaded_data.sign = SIGN_POS;
else
{
s = -s;
FPU_loaded_data.sign = SIGN_NEG;
}
e = EXP_BIAS + 15;
FPU_loaded_data.sigh = s << 16;
FPU_loaded_data.sigl = 0;
FPU_loaded_data.exp = e;
FPU_loaded_data.tag = TW_Valid;
normalize_nuo(&FPU_loaded_data);
}
/* Get a packed bcd array from user memory */
void reg_load_bcd(void)
{
char *s = (char *)FPU_data_address;
int pos;
unsigned char bcd;
long long l=0;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, s, 10);
RE_ENTRANT_CHECK_ON;
for ( pos = 8; pos >= 0; pos--)
{
l *= 10;
RE_ENTRANT_CHECK_OFF;
bcd = (unsigned char)get_fs_byte((unsigned char *) s+pos);
RE_ENTRANT_CHECK_ON;
l += bcd >> 4;
l *= 10;
l += bcd & 0x0f;
}
/* Finish all access to user memory before putting stuff into
the static FPU_loaded_data */
RE_ENTRANT_CHECK_OFF;
FPU_loaded_data.sign =
((unsigned char)get_fs_byte((unsigned char *) s+9)) & 0x80 ?
SIGN_NEG : SIGN_POS;
RE_ENTRANT_CHECK_ON;
if (l == 0)
{
char sign = FPU_loaded_data.sign;
reg_move(&CONST_Z, &FPU_loaded_data);
FPU_loaded_data.sign = sign;
}
else
{
significand(&FPU_loaded_data) = l;
FPU_loaded_data.exp = EXP_BIAS + 63;
FPU_loaded_data.tag = TW_Valid;
normalize_nuo(&FPU_loaded_data);
}
}
/*===========================================================================*/
/* Put a long double into user memory */
int reg_store_extended(void)
{
/*
The only exception raised by an attempt to store to an
extended format is the Invalid Stack exception, i.e.
attempting to store from an empty register.
*/
long double *d = (long double *)FPU_data_address;
if ( FPU_st0_tag != TW_Empty )
{
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE, d, 10);
RE_ENTRANT_CHECK_ON;
write_to_extended(FPU_st0_ptr, (char *) FPU_data_address);
return 1;
}
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
if ( control_word & CW_Invalid )
{
/* The masked response */
/* Put out the QNaN indefinite */
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,10);
put_fs_long(0, (unsigned long *) d);
put_fs_long(0xc0000000, 1 + (unsigned long *) d);
put_fs_word(0xffff, 4 + (short *) d);
RE_ENTRANT_CHECK_ON;
return 1;
}
else
return 0;
}
/* Put a double into user memory */
int reg_store_double(void)
{
double *dfloat = (double *)FPU_data_address;
unsigned long l[2];
unsigned long increment = 0; /* avoid gcc warnings */
if (FPU_st0_tag == TW_Valid)
{
int exp;
FPU_REG tmp;
reg_move(FPU_st0_ptr, &tmp);
exp = tmp.exp - EXP_BIAS;
if ( exp < DOUBLE_Emin ) /* It may be a denormal */
{
int precision_loss;
/* A denormal will always underflow. */
#ifndef PECULIAR_486
/* An 80486 is supposed to be able to generate
a denormal exception here, but... */
if ( FPU_st0_ptr->exp <= EXP_UNDER )
{
/* Underflow has priority. */
if ( control_word & CW_Underflow )
denormal_operand();
}
#endif PECULIAR_486
tmp.exp += -DOUBLE_Emin + 52; /* largest exp to be 51 */
if ( (precision_loss = round_to_int(&tmp)) )
{
#ifdef PECULIAR_486
/* Did it round to a non-denormal ? */
/* This behaviour might be regarded as peculiar, it appears
that the 80486 rounds to the dest precision, then
converts to decide underflow. */
if ( !((tmp.sigh == 0x00100000) && (tmp.sigl == 0) &&
(FPU_st0_ptr->sigl & 0x000007ff)) )
#endif PECULIAR_486
{
EXCEPTION(EX_Underflow);
/* This is a special case: see sec 16.2.5.1 of
the 80486 book */
if ( !(control_word & CW_Underflow) )
return 0;
}
EXCEPTION(precision_loss);
if ( !(control_word & CW_Precision) )
return 0;
}
l[0] = tmp.sigl;
l[1] = tmp.sigh;
}
else
{
if ( tmp.sigl & 0x000007ff )
{
switch (control_word & CW_RC)
{
case RC_RND:
/* Rounding can get a little messy.. */
increment = ((tmp.sigl & 0x7ff) > 0x400) | /* nearest */
((tmp.sigl & 0xc00) == 0xc00); /* odd -> even */
break;
case RC_DOWN: /* towards -infinity */
increment = (tmp.sign == SIGN_POS) ? 0 : tmp.sigl & 0x7ff;
break;
case RC_UP: /* towards +infinity */
increment = (tmp.sign == SIGN_POS) ? tmp.sigl & 0x7ff : 0;
break;
case RC_CHOP:
increment = 0;
break;
}
/* Truncate the mantissa */
tmp.sigl &= 0xfffff800;
if ( increment )
{
set_precision_flag_up();
if ( tmp.sigl >= 0xfffff800 )
{
/* the sigl part overflows */
if ( tmp.sigh == 0xffffffff )
{
/* The sigh part overflows */
tmp.sigh = 0x80000000;
exp++;
if (exp >= EXP_OVER)
goto overflow;
}
else
{
tmp.sigh ++;
}
tmp.sigl = 0x00000000;
}
else
{
/* We only need to increment sigl */
tmp.sigl += 0x00000800;
}
}
else
set_precision_flag_down();
}
l[0] = (tmp.sigl >> 11) | (tmp.sigh << 21);
l[1] = ((tmp.sigh >> 11) & 0xfffff);
if ( exp > DOUBLE_Emax )
{
overflow:
EXCEPTION(EX_Overflow);
if ( !(control_word & CW_Overflow) )
return 0;
set_precision_flag_up();
if ( !(control_word & CW_Precision) )
return 0;
/* This is a special case: see sec 16.2.5.1 of the 80486 book */
/* Overflow to infinity */
l[0] = 0x00000000; /* Set to */
l[1] = 0x7ff00000; /* + INF */
}
else
{
/* Add the exponent */
l[1] |= (((exp+DOUBLE_Ebias) & 0x7ff) << 20);
}
}
}
else if (FPU_st0_tag == TW_Zero)
{
/* Number is zero */
l[0] = 0;
l[1] = 0;
}
else if (FPU_st0_tag == TW_Infinity)
{
l[0] = 0;
l[1] = 0x7ff00000;
}
else if (FPU_st0_tag == TW_NaN)
{
/* See if we can get a valid NaN from the FPU_REG */
l[0] = (FPU_st0_ptr->sigl >> 11) | (FPU_st0_ptr->sigh << 21);
l[1] = ((FPU_st0_ptr->sigh >> 11) & 0xfffff);
if ( !(FPU_st0_ptr->sigh & 0x40000000) )
{
/* It is a signalling NaN */
EXCEPTION(EX_Invalid);
if ( !(control_word & CW_Invalid) )
return 0;
l[1] |= (0x40000000 >> 11);
}
l[1] |= 0x7ff00000;
}
else if ( FPU_st0_tag == TW_Empty )
{
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
if ( control_word & CW_Invalid )
{
/* The masked response */
/* Put out the QNaN indefinite */
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,(void *)dfloat,8);
put_fs_long(0, (unsigned long *) dfloat);
put_fs_long(0xfff80000, 1 + (unsigned long *) dfloat);
RE_ENTRANT_CHECK_ON;
return 1;
}
else
return 0;
}
if (FPU_st0_ptr->sign)
l[1] |= 0x80000000;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,(void *)dfloat,8);
put_fs_long(l[0], (unsigned long *)dfloat);
put_fs_long(l[1], 1 + (unsigned long *)dfloat);
RE_ENTRANT_CHECK_ON;
return 1;
}
/* Put a float into user memory */
int reg_store_single(void)
{
float *single = (float *)FPU_data_address;
long templ;
unsigned long increment = 0; /* avoid gcc warnings */
if (FPU_st0_tag == TW_Valid)
{
int exp;
FPU_REG tmp;
reg_move(FPU_st0_ptr, &tmp);
exp = tmp.exp - EXP_BIAS;
if ( exp < SINGLE_Emin )
{
int precision_loss;
/* A denormal will always underflow. */
#ifndef PECULIAR_486
/* An 80486 is supposed to be able to generate
a denormal exception here, but... */
if ( FPU_st0_ptr->exp <= EXP_UNDER )
{
/* Underflow has priority. */
if ( control_word & CW_Underflow )
denormal_operand();
}
#endif PECULIAR_486
tmp.exp += -SINGLE_Emin + 23; /* largest exp to be 22 */
if ( (precision_loss = round_to_int(&tmp)) )
{
#ifdef PECULIAR_486
/* Did it round to a non-denormal ? */
/* This behaviour might be regarded as peculiar, it appears
that the 80486 rounds to the dest precision, then
converts to decide underflow. */
if ( !((tmp.sigl == 0x00800000) &&
((FPU_st0_ptr->sigh & 0x000000ff) || FPU_st0_ptr->sigl)) )
#endif PECULIAR_486
{
EXCEPTION(EX_Underflow);
/* This is a special case: see sec 16.2.5.1 of
the 80486 book */
if ( !(control_word & EX_Underflow) )
return 0;
}
EXCEPTION(precision_loss);
if ( !(control_word & EX_Precision) )
return 0;
}
templ = tmp.sigl;
}
else
{
if ( tmp.sigl | (tmp.sigh & 0x000000ff) )
{
unsigned long sigh = tmp.sigh;
unsigned long sigl = tmp.sigl;
switch (control_word & CW_RC)
{
case RC_RND:
increment = ((sigh & 0xff) > 0x80) /* more than half */
|| (((sigh & 0xff) == 0x80) && sigl) /* more than half */
|| ((sigh & 0x180) == 0x180); /* round to even */
break;
case RC_DOWN: /* towards -infinity */
increment = (tmp.sign == SIGN_POS)
? 0 : (sigl | (sigh & 0xff));
break;
case RC_UP: /* towards +infinity */
increment = (tmp.sign == SIGN_POS)
? (sigl | (sigh & 0xff)) : 0;
break;
case RC_CHOP:
increment = 0;
break;
}
/* Truncate part of the mantissa */
tmp.sigl = 0;
if (increment)
{
set_precision_flag_up();
if ( sigh >= 0xffffff00 )
{
/* The sigh part overflows */
tmp.sigh = 0x80000000;
exp++;
if ( exp >= EXP_OVER )
goto overflow;
}
else
{
tmp.sigh &= 0xffffff00;
tmp.sigh += 0x100;
}
}
else
{
set_precision_flag_down();
tmp.sigh &= 0xffffff00; /* Finish the truncation */
}
}
templ = (tmp.sigh >> 8) & 0x007fffff;
if ( exp > SINGLE_Emax )
{
overflow:
EXCEPTION(EX_Overflow);
if ( !(control_word & CW_Overflow) )
return 0;
set_precision_flag_up();
if ( !(control_word & CW_Precision) )
return 0;
/* This is a special case: see sec 16.2.5.1 of the 80486 book. */
/* Masked respose is overflow to infinity. */
templ = 0x7f800000;
}
else
templ |= ((exp+SINGLE_Ebias) & 0xff) << 23;
}
}
else if (FPU_st0_tag == TW_Zero)
{
templ = 0;
}
else if (FPU_st0_tag == TW_Infinity)
{
templ = 0x7f800000;
}
else if (FPU_st0_tag == TW_NaN)
{
/* See if we can get a valid NaN from the FPU_REG */
templ = FPU_st0_ptr->sigh >> 8;
if ( !(FPU_st0_ptr->sigh & 0x40000000) )
{
/* It is a signalling NaN */
EXCEPTION(EX_Invalid);
if ( !(control_word & CW_Invalid) )
return 0;
templ |= (0x40000000 >> 8);
}
templ |= 0x7f800000;
}
else if ( FPU_st0_tag == TW_Empty )
{
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
if ( control_word & EX_Invalid )
{
/* The masked response */
/* Put out the QNaN indefinite */
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,(void *)single,4);
put_fs_long(0xffc00000, (unsigned long *) single);
RE_ENTRANT_CHECK_ON;
return 1;
}
else
return 0;
}
#ifdef PARANOID
else
{
EXCEPTION(EX_INTERNAL|0x106);
return 0;
}
#endif
if (FPU_st0_ptr->sign)
templ |= 0x80000000;
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,(void *)single,4);
put_fs_long(templ,(unsigned long *) single);
RE_ENTRANT_CHECK_ON;
return 1;
}
/* Put a long long into user memory */
int reg_store_int64(void)
{
long long *d = (long long *)FPU_data_address;
FPU_REG t;
long long tll;
int precision_loss;
if ( FPU_st0_tag == TW_Empty )
{
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
goto invalid_operand;
}
else if ( (FPU_st0_tag == TW_Infinity) ||
(FPU_st0_tag == TW_NaN) )
{
EXCEPTION(EX_Invalid);
goto invalid_operand;
}
reg_move(FPU_st0_ptr, &t);
precision_loss = round_to_int(&t);
((long *)&tll)[0] = t.sigl;
((long *)&tll)[1] = t.sigh;
if ( (precision_loss == 1) ||
((t.sigh & 0x80000000) &&
!((t.sigh == 0x80000000) && (t.sigl == 0) &&
(t.sign == SIGN_NEG))) )
{
EXCEPTION(EX_Invalid);
/* This is a special case: see sec 16.2.5.1 of the 80486 book */
invalid_operand:
if ( control_word & EX_Invalid )
{
/* Produce something like QNaN "indefinite" */
tll = 0x8000000000000000LL;
}
else
return 0;
}
else
{
if ( precision_loss )
set_precision_flag(precision_loss);
if ( t.sign )
tll = - tll;
}
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,(void *)d,8);
put_fs_long(((long *)&tll)[0],(unsigned long *) d);
put_fs_long(((long *)&tll)[1],1 + (unsigned long *) d);
RE_ENTRANT_CHECK_ON;
return 1;
}
/* Put a long into user memory */
int reg_store_int32(void)
{
long *d = (long *)FPU_data_address;
FPU_REG t;
int precision_loss;
if ( FPU_st0_tag == TW_Empty )
{
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
goto invalid_operand;
}
else if ( (FPU_st0_tag == TW_Infinity) ||
(FPU_st0_tag == TW_NaN) )
{
EXCEPTION(EX_Invalid);
goto invalid_operand;
}
reg_move(FPU_st0_ptr, &t);
precision_loss = round_to_int(&t);
if (t.sigh ||
((t.sigl & 0x80000000) &&
!((t.sigl == 0x80000000) && (t.sign == SIGN_NEG))) )
{
EXCEPTION(EX_Invalid);
/* This is a special case: see sec 16.2.5.1 of the 80486 book */
invalid_operand:
if ( control_word & EX_Invalid )
{
/* Produce something like QNaN "indefinite" */
t.sigl = 0x80000000;
}
else
return 0;
}
else
{
if ( precision_loss )
set_precision_flag(precision_loss);
if ( t.sign )
t.sigl = -(long)t.sigl;
}
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,4);
put_fs_long(t.sigl, (unsigned long *) d);
RE_ENTRANT_CHECK_ON;
return 1;
}
/* Put a short into user memory */
int reg_store_int16(void)
{
short *d = (short *)FPU_data_address;
FPU_REG t;
int precision_loss;
if ( FPU_st0_tag == TW_Empty )
{
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
goto invalid_operand;
}
else if ( (FPU_st0_tag == TW_Infinity) ||
(FPU_st0_tag == TW_NaN) )
{
EXCEPTION(EX_Invalid);
goto invalid_operand;
}
reg_move(FPU_st0_ptr, &t);
precision_loss = round_to_int(&t);
if (t.sigh ||
((t.sigl & 0xffff8000) &&
!((t.sigl == 0x8000) && (t.sign == SIGN_NEG))) )
{
EXCEPTION(EX_Invalid);
/* This is a special case: see sec 16.2.5.1 of the 80486 book */
invalid_operand:
if ( control_word & EX_Invalid )
{
/* Produce something like QNaN "indefinite" */
t.sigl = 0x8000;
}
else
return 0;
}
else
{
if ( precision_loss )
set_precision_flag(precision_loss);
if ( t.sign )
t.sigl = -t.sigl;
}
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,2);
put_fs_word((short)t.sigl,(short *) d);
RE_ENTRANT_CHECK_ON;
return 1;
}
/* Put a packed bcd array into user memory */
int reg_store_bcd(void)
{
char *d = (char *)FPU_data_address;
FPU_REG t;
unsigned long long ll;
unsigned char b;
int i, precision_loss;
unsigned char sign = (FPU_st0_ptr->sign == SIGN_NEG) ? 0x80 : 0;
if ( FPU_st0_tag == TW_Empty )
{
/* Empty register (stack underflow) */
EXCEPTION(EX_StackUnder);
goto invalid_operand;
}
reg_move(FPU_st0_ptr, &t);
precision_loss = round_to_int(&t);
ll = significand(&t);
/* Check for overflow, by comparing with 999999999999999999 decimal. */
if ( (t.sigh > 0x0de0b6b3) ||
((t.sigh == 0x0de0b6b3) && (t.sigl > 0xa763ffff)) )
{
EXCEPTION(EX_Invalid);
/* This is a special case: see sec 16.2.5.1 of the 80486 book */
invalid_operand:
if ( control_word & CW_Invalid )
{
/* Produce the QNaN "indefinite" */
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,10);
for ( i = 0; i < 7; i++)
put_fs_byte(0, (unsigned char *) d+i); /* These bytes "undefined" */
put_fs_byte(0xc0, (unsigned char *) d+7); /* This byte "undefined" */
put_fs_byte(0xff, (unsigned char *) d+8);
put_fs_byte(0xff, (unsigned char *) d+9);
RE_ENTRANT_CHECK_ON;
return 1;
}
else
return 0;
}
else if ( precision_loss )
{
/* Precision loss doesn't stop the data transfer */
set_precision_flag(precision_loss);
}
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,10);
RE_ENTRANT_CHECK_ON;
for ( i = 0; i < 9; i++)
{
b = div_small(&ll, 10);
b |= (div_small(&ll, 10)) << 4;
RE_ENTRANT_CHECK_OFF;
put_fs_byte(b,(unsigned char *) d+i);
RE_ENTRANT_CHECK_ON;
}
RE_ENTRANT_CHECK_OFF;
put_fs_byte(sign,(unsigned char *) d+9);
RE_ENTRANT_CHECK_ON;
return 1;
}
/*===========================================================================*/
/* r gets mangled such that sig is int, sign:
it is NOT normalized */
/* The return value (in eax) is zero if the result is exact,
if bits are changed due to rounding, truncation, etc, then
a non-zero value is returned */
/* Overflow is signalled by a non-zero return value (in eax).
In the case of overflow, the returned significand always has the
the largest possible value */
int round_to_int(FPU_REG *r)
{
char very_big;
unsigned eax;
if (r->tag == TW_Zero)
{
/* Make sure that zero is returned */
significand(r) = 0;
return 0; /* o.k. */
}
if (r->exp > EXP_BIAS + 63)
{
r->sigl = r->sigh = ~0; /* The largest representable number */
return 1; /* overflow */
}
eax = shrxs(&r->sigl, EXP_BIAS + 63 - r->exp);
very_big = !(~(r->sigh) | ~(r->sigl)); /* test for 0xfff...fff */
#define half_or_more (eax & 0x80000000)
#define frac_part (eax)
#define more_than_half ((eax & 0x80000001) == 0x80000001)
switch (control_word & CW_RC)
{
case RC_RND:
if ( more_than_half /* nearest */
|| (half_or_more && (r->sigl & 1)) ) /* odd -> even */
{
if ( very_big ) return 1; /* overflow */
significand(r) ++;
return PRECISION_LOST_UP;
}
break;
case RC_DOWN:
if (frac_part && r->sign)
{
if ( very_big ) return 1; /* overflow */
significand(r) ++;
return PRECISION_LOST_UP;
}
break;
case RC_UP:
if (frac_part && !r->sign)
{
if ( very_big ) return 1; /* overflow */
significand(r) ++;
return PRECISION_LOST_UP;
}
break;
case RC_CHOP:
break;
}
return eax ? PRECISION_LOST_DOWN : 0;
}
/*===========================================================================*/
char *fldenv(fpu_addr_modes addr_modes)
{
char *s = (char *)FPU_data_address;
unsigned short tag_word = 0;
unsigned char tag;
int i;
if ( addr_modes.vm86
|| (addr_modes.override.operand_size == OP_SIZE_PREFIX) )
{
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, s, 0x0e);
control_word = get_fs_word((unsigned short *) s);
partial_status = get_fs_word((unsigned short *) (s+2));
tag_word = get_fs_word((unsigned short *) (s+4));
ip_offset = get_fs_word((unsigned short *) (s+6));
cs_selector = get_fs_word((unsigned short *) (s+8));
data_operand_offset = get_fs_word((unsigned short *) (s+0x0a));
operand_selector = get_fs_word((unsigned short *) (s+0x0c));
RE_ENTRANT_CHECK_ON;
s += 0x0e;
if ( addr_modes.vm86 )
{
ip_offset += (cs_selector & 0xf000) << 4;
data_operand_offset += (operand_selector & 0xf000) << 4;
}
}
else
{
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_READ, s, 0x1c);
control_word = get_fs_word((unsigned short *) s);
partial_status = get_fs_word((unsigned short *) (s+4));
tag_word = get_fs_word((unsigned short *) (s+8));
ip_offset = get_fs_long((unsigned long *) (s+0x0c));
cs_selector = get_fs_long((unsigned long *) (s+0x10));
data_operand_offset = get_fs_long((unsigned long *) (s+0x14));
operand_selector = get_fs_long((unsigned long *) (s+0x18));
RE_ENTRANT_CHECK_ON;
s += 0x1c;
}
#ifdef PECULIAR_486
control_word &= ~0xe080;
#endif PECULIAR_486
top = (partial_status >> SW_Top_Shift) & 7;
if ( partial_status & ~control_word & CW_Exceptions )
partial_status |= (SW_Summary | SW_Backward);
else
partial_status &= ~(SW_Summary | SW_Backward);
for ( i = 0; i < 8; i++ )
{
tag = tag_word & 3;
tag_word >>= 2;
if ( tag == 3 )
/* New tag is empty. Accept it */
regs[i].tag = TW_Empty;
else if ( regs[i].tag == TW_Empty )
{
/* Old tag is empty and new tag is not empty. New tag is determined
by old reg contents */
if ( regs[i].exp == EXP_BIAS - EXTENDED_Ebias )
{
if ( !(regs[i].sigl | regs[i].sigh) )
regs[i].tag = TW_Zero;
else
regs[i].tag = TW_Valid;
}
else if ( regs[i].exp == 0x7fff + EXP_BIAS - EXTENDED_Ebias )
{
if ( !((regs[i].sigh & ~0x80000000) | regs[i].sigl) )
regs[i].tag = TW_Infinity;
else
regs[i].tag = TW_NaN;
}
else
regs[i].tag = TW_Valid;
}
/* Else old tag is not empty and new tag is not empty. Old tag
remains correct */
}
/* Ensure that the values just loaded are not changed by
fix-up operations. */
NO_NET_DATA_EFFECT;
NO_NET_INSTR_EFFECT;
return s;
}
void frstor(fpu_addr_modes addr_modes)
{
int i, stnr;
unsigned char tag;
char *s = fldenv(addr_modes);
for ( i = 0; i < 8; i++ )
{
/* Load each register. */
FPU_data_address = (void *)(s+i*10);
reg_load_extended();
stnr = (i+top) & 7;
tag = regs[stnr].tag; /* Derived from the loaded tag word. */
reg_move(&FPU_loaded_data, ®s[stnr]);
if ( tag == TW_Empty ) /* The loaded data over-rides all other cases. */
regs[stnr].tag = tag;
}
/* Reverse the effect which loading the registers had on the
data pointer */
NO_NET_DATA_EFFECT;
}
unsigned short tag_word(void)
{
unsigned short word = 0;
unsigned char tag;
int i;
for ( i = 7; i >= 0; i-- )
{
switch ( tag = regs[i].tag )
{
case TW_Valid:
if ( regs[i].exp <= (EXP_BIAS - EXTENDED_Ebias) )
tag = 2;
break;
case TW_Infinity:
case TW_NaN:
tag = 2;
break;
case TW_Empty:
tag = 3;
break;
/* TW_Zero already has the correct value */
}
word <<= 2;
word |= tag;
}
return word;
}
char *fstenv(fpu_addr_modes addr_modes)
{
char *d = (char *)FPU_data_address;
if ( addr_modes.vm86
|| (addr_modes.override.operand_size == OP_SIZE_PREFIX) )
{
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,14);
#ifdef PECULIAR_486
put_fs_long(control_word & ~0xe080, (unsigned short *) d);
#else
put_fs_word(control_word, (unsigned short *) d);
#endif PECULIAR_486
put_fs_word(status_word(), (unsigned short *) (d+2));
put_fs_word(tag_word(), (unsigned short *) (d+4));
put_fs_word(ip_offset, (unsigned short *) (d+6));
put_fs_word(data_operand_offset, (unsigned short *) (d+0x0a));
if ( addr_modes.vm86 )
{
put_fs_word((ip_offset & 0xf0000) >> 4,
(unsigned short *) (d+8));
put_fs_word((data_operand_offset & 0xf0000) >> 4,
(unsigned short *) (d+0x0c));
}
else
{
put_fs_word(cs_selector, (unsigned short *) (d+8));
put_fs_word(operand_selector, (unsigned short *) (d+0x0c));
}
RE_ENTRANT_CHECK_ON;
d += 0x0e;
}
else
{
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,28);
#ifdef PECULIAR_486
/* An 80486 sets all the reserved bits to 1. */
put_fs_long(0xffff0040 | (control_word & ~0xe080), (unsigned long *) d);
put_fs_long(0xffff0000 | status_word(), (unsigned long *) (d+4));
put_fs_long(0xffff0000 | tag_word(), (unsigned long *) (d+8));
#else
put_fs_word(control_word, (unsigned short *) d);
put_fs_word(status_word(), (unsigned short *) (d+4));
put_fs_word(tag_word(), (unsigned short *) (d+8));
#endif PECULIAR_486
put_fs_long(ip_offset, (unsigned long *) (d+0x0c));
put_fs_long(cs_selector & ~0xf8000000, (unsigned long *) (d+0x10));
put_fs_long(data_operand_offset, (unsigned long *) (d+0x14));
#ifdef PECULIAR_486
/* An 80486 sets all the reserved bits to 1. */
put_fs_long(0xffff0000 | operand_selector, (unsigned long *) (d+0x18));
#else
put_fs_long(operand_selector, (unsigned long *) (d+0x18));
#endif PECULIAR_486
RE_ENTRANT_CHECK_ON;
d += 0x1c;
}
control_word |= CW_Exceptions;
partial_status &= ~(SW_Summary | SW_Backward);
return d;
}
void fsave(fpu_addr_modes addr_modes)
{
char *d;
int i;
d = fstenv(addr_modes);
RE_ENTRANT_CHECK_OFF;
FPU_verify_area(VERIFY_WRITE,d,80);
RE_ENTRANT_CHECK_ON;
for ( i = 0; i < 8; i++ )
write_to_extended(®s[(top + i) & 7], d + 10 * i);
finit();
}
/*===========================================================================*/
/*
A call to this function must be preceeded by a call to
FPU_verify_area() to verify access to the 10 bytes at d
*/
static void write_to_extended(FPU_REG *rp, char *d)
{
long e;
FPU_REG tmp;
e = rp->exp - EXP_BIAS + EXTENDED_Ebias;
#ifdef PARANOID
switch ( rp->tag )
{
case TW_Zero:
if ( rp->sigh | rp->sigl | e )
EXCEPTION(EX_INTERNAL | 0x114);
break;
case TW_Infinity:
case TW_NaN:
if ( (e ^ 0x7fff) | !(rp->sigh & 0x80000000) )
EXCEPTION(EX_INTERNAL | 0x114);
break;
default:
if (e > 0x7fff || e < -63)
EXCEPTION(EX_INTERNAL | 0x114);
}
#endif PARANOID
/*
All numbers except denormals are stored internally in a
format which is compatible with the extended real number
format.
*/
if ( e > 0 )
{
/* just copy the reg */
RE_ENTRANT_CHECK_OFF;
put_fs_long(rp->sigl, (unsigned long *) d);
put_fs_long(rp->sigh, (unsigned long *) (d + 4));
RE_ENTRANT_CHECK_ON;
}
else
{
/*
The number is a de-normal stored as a normal using our
extra exponent range, or is Zero.
Convert it back to a de-normal, or leave it as Zero.
*/
reg_move(rp, &tmp);
tmp.exp += -EXTENDED_Emin + 63; /* largest exp to be 63 */
round_to_int(&tmp);
e = 0;
RE_ENTRANT_CHECK_OFF;
put_fs_long(tmp.sigl, (unsigned long *) d);
put_fs_long(tmp.sigh, (unsigned long *) (d + 4));
RE_ENTRANT_CHECK_ON;
}
e |= rp->sign == SIGN_POS ? 0 : 0x8000;
RE_ENTRANT_CHECK_OFF;
put_fs_word(e, (unsigned short *) (d + 8));
RE_ENTRANT_CHECK_ON;
}
