of the floating point routines in libgcc1.c for targets without
hardware floating point. */
-/* Copyright 1994-2015 Free Software Foundation, Inc.
+/* Copyright 1994-2021 Free Software Foundation, Inc.
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
#ifndef SIM_FPU_C
#define SIM_FPU_C
+/* This must come before any other includes. */
+#include "defs.h"
+
#include "sim-basics.h"
#include "sim-fpu.h"
#include "sim-io.h"
#include "sim-assert.h"
+#include <stdlib.h>
/* Debugging support.
If digits is -1, then print all digits. */
print (arg, "0");
bit >>= 1;
- if (digits > 0) digits--;
+ if (digits > 0)
+ digits--;
i = (i + 1) % 4;
}
}
-/* Quick and dirty conversion between a host double and host 64bit int */
+/* Quick and dirty conversion between a host double and host 64bit int. */
-typedef union {
+typedef union
+{
double d;
unsigned64 i;
} sim_fpu_map;
#define MAX_UINT (is_64bit ? MAX_UINT64 : MAX_UINT32)
#define NR_INTBITS (is_64bit ? 64 : 32)
-/* Squeese an unpacked sim_fpu struct into a 32/64 bit integer */
+/* Squeeze an unpacked sim_fpu struct into a 32/64 bit integer. */
STATIC_INLINE_SIM_FPU (unsigned64)
pack_fpu (const sim_fpu *src,
int is_double)
switch (src->class)
{
- /* create a NaN */
+ /* Create a NaN. */
case sim_fpu_class_qnan:
sign = src->sign;
exp = EXPMAX;
- /* force fraction to correct class */
+ /* Force fraction to correct class. */
fraction = src->fraction;
fraction >>= NR_GUARDS;
#ifdef SIM_QUIET_NAN_NEGATED
case sim_fpu_class_snan:
sign = src->sign;
exp = EXPMAX;
- /* force fraction to correct class */
+ /* Force fraction to correct class. */
fraction = src->fraction;
fraction >>= NR_GUARDS;
#ifdef SIM_QUIET_NAN_NEGATED
int nr_shift = NORMAL_EXPMIN - src->normal_exp;
if (nr_shift > NR_FRACBITS)
{
- /* underflow, just make the number zero */
+ /* Underflow, just make the number zero. */
sign = src->sign;
exp = 0;
fraction = 0;
{
sign = src->sign;
exp = 0;
- /* Shift by the value */
+ /* Shift by the value. */
fraction = src->fraction;
fraction >>= NR_GUARDS;
fraction >>= nr_shift;
sign = src->sign;
fraction = src->fraction;
/* FIXME: Need to round according to WITH_SIM_FPU_ROUNDING
- or some such */
+ or some such. */
/* Round to nearest: If the guard bits are the all zero, but
the first, then we're half way between two numbers,
choose the one which makes the lsb of the answer 0. */
}
else
{
- /* Add a one to the guards to force round to nearest */
+ /* Add a one to the guards to force round to nearest. */
fraction += GUARDROUND;
}
- if ((fraction & IMPLICIT_2)) /* rounding resulted in carry */
+ if ((fraction & IMPLICIT_2)) /* Rounding resulted in carry. */
{
exp += 1;
fraction >>= 1;
}
fraction >>= NR_GUARDS;
/* When exp == EXPMAX (overflow from carry) fraction must
- have been made zero */
+ have been made zero. */
ASSERT ((exp == EXPMAX) <= ((fraction & ~IMPLICIT_1) == 0));
}
break;
| (exp << NR_FRACBITS)
| LSMASKED64 (fraction, NR_FRACBITS - 1, 0));
- /* trace operation */
+ /* Trace operation. */
#if 0
if (is_double)
{
}
-/* Unpack a 32/64 bit integer into a sim_fpu structure */
+/* Unpack a 32/64 bit integer into a sim_fpu structure. */
STATIC_INLINE_SIM_FPU (void)
unpack_fpu (sim_fpu *dst, unsigned64 packed, int is_double)
{
/* Hmm. Looks like 0 */
if (fraction == 0)
{
- /* tastes like zero */
+ /* Tastes like zero. */
dst->class = sim_fpu_class_zero;
dst->sign = sign;
dst->normal_exp = 0;
/* Huge exponent*/
if (fraction == 0)
{
- /* Attached to a zero fraction - means infinity */
+ /* Attached to a zero fraction - means infinity. */
dst->class = sim_fpu_class_infinity;
dst->sign = sign;
/* dst->normal_exp = EXPBIAS; */
{
int qnan;
- /* Non zero fraction, means NaN */
+ /* Non zero fraction, means NaN. */
dst->sign = sign;
dst->fraction = (fraction << NR_GUARDS);
#ifdef SIM_QUIET_NAN_NEGATED
}
else
{
- /* Nothing strange about this number */
+ /* Nothing strange about this number. */
dst->class = sim_fpu_class_number;
dst->sign = sign;
dst->fraction = ((fraction << NR_GUARDS) | IMPLICIT_1);
dst->normal_exp = exp - EXPBIAS;
}
- /* trace operation */
+ /* Trace operation. */
#if 0
if (is_double)
{
}
-/* Convert a floating point into an integer */
+/* Convert a floating point into an integer. */
STATIC_INLINE_SIM_FPU (int)
fpu2i (signed64 *i,
const sim_fpu *s,
*i = MIN_INT; /* FIXME */
return sim_fpu_status_invalid_cvi;
}
- /* map infinity onto MAX_INT... */
+ /* Map infinity onto MAX_INT... */
if (sim_fpu_is_infinity (s))
{
*i = s->sign ? MIN_INT : MAX_INT;
return sim_fpu_status_invalid_cvi;
}
- /* it is a number, but a small one */
+ /* It is a number, but a small one. */
if (s->normal_exp < 0)
{
*i = 0;
return 0; /* exact */
if (is_64bit) /* can't round */
return sim_fpu_status_invalid_cvi; /* must be overflow */
- /* For a 32bit with MAX_INT, rounding is possible */
+ /* For a 32bit with MAX_INT, rounding is possible. */
switch (round)
{
case sim_fpu_round_default:
*i = s->sign ? MIN_INT : MAX_INT;
return sim_fpu_status_invalid_cvi;
}
- /* normal number shift it into place */
+ /* Normal number, shift it into place. */
tmp = s->fraction;
shift = (s->normal_exp - (NR_FRAC_GUARD));
if (shift > 0)
return status;
}
-/* convert an integer into a floating point */
+/* Convert an integer into a floating point. */
STATIC_INLINE_SIM_FPU (int)
i2fpu (sim_fpu *f, signed64 i, int is_64bit)
{
if (f->sign)
{
/* Special case for minint, since there is no corresponding
- +ve integer representation for it */
+ +ve integer representation for it. */
if (i == MIN_INT)
{
f->fraction = IMPLICIT_1;
}
-/* Convert a floating point into an integer */
+/* Convert a floating point into an integer. */
STATIC_INLINE_SIM_FPU (int)
fpu2u (unsigned64 *u, const sim_fpu *s, int is_64bit)
{
*u = 0;
return 0;
}
- /* it is a negative number */
+ /* It is a negative number. */
if (s->sign)
{
*u = 0;
return 0;
}
- /* get reasonable MAX_USI_INT... */
+ /* Get reasonable MAX_USI_INT... */
if (sim_fpu_is_infinity (s))
{
*u = MAX_UINT;
return 0;
}
- /* it is a number, but a small one */
+ /* It is a number, but a small one. */
if (s->normal_exp < 0)
{
*u = 0;
return 0;
}
-/* Convert an unsigned integer into a floating point */
+/* Convert an unsigned integer into a floating point. */
STATIC_INLINE_SIM_FPU (int)
u2fpu (sim_fpu *f, unsigned64 u, int is_64bit)
{
f->class = sim_fpu_class_number;
f->sign = sign;
f->normal_exp = normal_exp;
- /* shift the fraction to where sim-fpu expects it */
+ /* Shift the fraction to where sim-fpu expects it. */
if (shift >= 0)
f->fraction = (fraction << shift);
else
sim_fpu_tofraction (const sim_fpu *d,
int precision)
{
- /* we have NR_FRAC_GUARD bits, we want only PRECISION bits */
+ /* We have NR_FRAC_GUARD bits, we want only PRECISION bits. */
int shift = (NR_FRAC_GUARD - precision);
unsigned64 fraction = (d->fraction & ~IMPLICIT_1);
if (shift >= 0)
/* Round a number using NR_GUARDS.
- Will return the rounded number or F->FRACTION == 0 when underflow */
+ Will return the rounded number or F->FRACTION == 0 when underflow. */
STATIC_INLINE_SIM_FPU (int)
do_normal_round (sim_fpu *f,
break;
}
f->fraction &= ~guardmask;
- /* round if needed, handle resulting overflow */
+ /* Round if needed, handle resulting overflow. */
if ((status & sim_fpu_status_rounded))
{
f->fraction += fraclsb;
return 0;
break;
case sim_fpu_class_snan:
- /* Quieten a SignalingNaN */
+ /* Quieten a SignalingNaN. */
f->class = sim_fpu_class_qnan;
return sim_fpu_status_invalid_snan;
break;
&& !(denorm & sim_fpu_denorm_zero))
{
status = do_normal_round (f, shift + NR_GUARDS, round);
- if (f->fraction == 0) /* rounding underflowed */
+ if (f->fraction == 0) /* Rounding underflowed. */
{
status |= do_normal_underflow (f, is_double, round);
}
before rounding, some after! */
if (status & sim_fpu_status_inexact)
status |= sim_fpu_status_underflow;
- /* Flag that resultant value has been denormalized */
+ /* Flag that resultant value has been denormalized. */
f->class = sim_fpu_class_denorm;
}
else if ((denorm & sim_fpu_denorm_underflow_inexact))
/* f->class = sim_fpu_class_zero; */
status |= do_normal_underflow (f, is_double, round);
else if (f->normal_exp > NORMAL_EXPMAX)
- /* oops! rounding caused overflow */
+ /* Oops! rounding caused overflow. */
status |= do_normal_overflow (f, is_double, round);
}
ASSERT ((f->class == sim_fpu_class_number
/* use exp of larger */
if (shift >= NR_FRAC_GUARD)
{
- /* left has much bigger magnitute */
+ /* left has much bigger magnitude */
*f = *l;
return sim_fpu_status_inexact;
}
if (shift <= - NR_FRAC_GUARD)
{
- /* right has much bigger magnitute */
+ /* right has much bigger magnitude */
*f = *r;
return sim_fpu_status_inexact;
}
if (rfraction & LSMASK64 (shift - 1, 0))
{
status |= sim_fpu_status_inexact;
- rfraction |= LSBIT64 (shift); /* stick LSBit */
+ rfraction |= LSBIT64 (shift); /* Stick LSBit. */
}
rfraction >>= shift;
}
if (lfraction & LSMASK64 (- shift - 1, 0))
{
status |= sim_fpu_status_inexact;
- lfraction |= LSBIT64 (- shift); /* stick LSBit */
+ lfraction |= LSBIT64 (- shift); /* Stick LSBit. */
}
lfraction >>= -shift;
}
f->normal_exp = r->normal_exp;
}
- /* perform the addition */
+ /* Perform the addition. */
if (l->sign)
lfraction = - lfraction;
if (r->sign)
/* sign? */
f->class = sim_fpu_class_number;
- if ((signed64) f->fraction >= 0)
+ if (((signed64) f->fraction) >= 0)
f->sign = 0;
else
{
f->fraction = - f->fraction;
}
- /* normalize it */
+ /* Normalize it. */
if ((f->fraction & IMPLICIT_2))
{
f->fraction = (f->fraction >> 1) | (f->fraction & 1);
/* use exp of larger */
if (shift >= NR_FRAC_GUARD)
{
- /* left has much bigger magnitute */
+ /* left has much bigger magnitude */
*f = *l;
return sim_fpu_status_inexact;
}
if (shift <= - NR_FRAC_GUARD)
{
- /* right has much bigger magnitute */
+ /* right has much bigger magnitude */
*f = *r;
f->sign = !r->sign;
return sim_fpu_status_inexact;
if (rfraction & LSMASK64 (shift - 1, 0))
{
status |= sim_fpu_status_inexact;
- rfraction |= LSBIT64 (shift); /* stick LSBit */
+ rfraction |= LSBIT64 (shift); /* Stick LSBit. */
}
rfraction >>= shift;
}
if (lfraction & LSMASK64 (- shift - 1, 0))
{
status |= sim_fpu_status_inexact;
- lfraction |= LSBIT64 (- shift); /* stick LSBit */
+ lfraction |= LSBIT64 (- shift); /* Stick LSBit. */
}
lfraction >>= -shift;
}
f->normal_exp = r->normal_exp;
}
- /* perform the subtraction */
+ /* Perform the subtraction. */
if (l->sign)
lfraction = - lfraction;
if (!r->sign)
/* sign? */
f->class = sim_fpu_class_number;
- if ((signed64) f->fraction >= 0)
+ if (((signed64) f->fraction) >= 0)
f->sign = 0;
else
{
f->fraction = - f->fraction;
}
- /* normalize it */
+ /* Normalize it. */
if ((f->fraction & IMPLICIT_2))
{
f->fraction = (f->fraction >> 1) | (f->fraction & 1);
return 0;
}
/* Calculate the mantissa by multiplying both 64bit numbers to get a
- 128 bit number */
+ 128 bit number. */
{
unsigned64 low;
unsigned64 high;
ASSERT (high >= LSBIT64 ((NR_FRAC_GUARD * 2) - 64));
ASSERT (LSBIT64 (((NR_FRAC_GUARD + 1) * 2) - 64) < IMPLICIT_1);
- /* normalize */
+ /* Normalize. */
do
{
f->normal_exp--;
}
/* Calculate the mantissa by multiplying both 64bit numbers to get a
- 128 bit number */
+ 128 bit number. */
{
/* quotient = ( ( numerator / denominator)
x 2^(numerator exponent - denominator exponent)
}
ASSERT (numerator >= denominator);
- /* Gain extra precision, already used one spare bit */
+ /* Gain extra precision, already used one spare bit. */
numerator <<= NR_SPARE;
denominator <<= NR_SPARE;
numerator <<= 1;
}
- /* discard (but save) the extra bits */
+ /* Discard (but save) the extra bits. */
if ((quotient & LSMASK64 (NR_SPARE -1, 0)))
quotient = (quotient >> NR_SPARE) | 1;
else
ASSERT (f->fraction >= IMPLICIT_1 && f->fraction < IMPLICIT_2);
if (numerator != 0)
{
- f->fraction |= 1; /* stick remaining bits */
+ f->fraction |= 1; /* Stick remaining bits. */
return sim_fpu_status_inexact;
}
else
}
+INLINE_SIM_FPU (int)
+sim_fpu_rem (sim_fpu *f,
+ const sim_fpu *l,
+ const sim_fpu *r)
+{
+ if (sim_fpu_is_snan (l))
+ {
+ *f = *l;
+ f->class = sim_fpu_class_qnan;
+ return sim_fpu_status_invalid_snan;
+ }
+ if (sim_fpu_is_snan (r))
+ {
+ *f = *r;
+ f->class = sim_fpu_class_qnan;
+ return sim_fpu_status_invalid_snan;
+ }
+ if (sim_fpu_is_qnan (l))
+ {
+ *f = *l;
+ f->class = sim_fpu_class_qnan;
+ return 0;
+ }
+ if (sim_fpu_is_qnan (r))
+ {
+ *f = *r;
+ f->class = sim_fpu_class_qnan;
+ return 0;
+ }
+ if (sim_fpu_is_infinity (l))
+ {
+ *f = sim_fpu_qnan;
+ return sim_fpu_status_invalid_irx;
+ }
+ if (sim_fpu_is_zero (r))
+ {
+ *f = sim_fpu_qnan;
+ return sim_fpu_status_invalid_div0;
+ }
+ if (sim_fpu_is_zero (l))
+ {
+ *f = *l;
+ return 0;
+ }
+ if (sim_fpu_is_infinity (r))
+ {
+ *f = *l;
+ return 0;
+ }
+ {
+ sim_fpu n, tmp;
+
+ /* Remainder is calculated as l-n*r, where n is l/r rounded to the
+ nearest integer. The variable n is rounded half even. */
+
+ sim_fpu_div (&n, l, r);
+ sim_fpu_round_64 (&n, 0, 0);
+
+ if (n.normal_exp < -1) /* If n looks like zero just return l. */
+ {
+ *f = *l;
+ return 0;
+ }
+ else if (n.class == sim_fpu_class_number
+ && n.normal_exp <= (NR_FRAC_GUARD)) /* If not too large round. */
+ do_normal_round (&n, (NR_FRAC_GUARD) - n.normal_exp, sim_fpu_round_near);
+
+ /* Mark 0's as zero so multiply can detect zero. */
+ if (n.fraction == 0)
+ n.class = sim_fpu_class_zero;
+
+ /* Calculate n*r. */
+ sim_fpu_mul (&tmp, &n, r);
+ sim_fpu_round_64 (&tmp, 0, 0);
+
+ /* Finally calculate l-n*r. */
+ sim_fpu_sub (f, l, &tmp);
+
+ return 0;
+ }
+}
+
+
INLINE_SIM_FPU (int)
sim_fpu_max (sim_fpu *f,
const sim_fpu *l,
if (l->sign)
*f = *r; /* -inf < anything */
else
- *f = *l; /* +inf > anthing */
+ *f = *l; /* +inf > anything */
return 0;
}
if (sim_fpu_is_infinity (r))
if (r->sign)
*f = *l; /* anything > -inf */
else
- *f = *r; /* anthing < +inf */
+ *f = *r; /* anything < +inf */
return 0;
}
if (l->sign > r->sign)
}
ASSERT (l->sign == r->sign);
if (l->normal_exp > r->normal_exp
- || (l->normal_exp == r->normal_exp &&
- l->fraction > r->fraction))
+ || (l->normal_exp == r->normal_exp
+ && l->fraction > r->fraction))
{
/* |l| > |r| */
if (l->sign)
}
ASSERT (l->sign == r->sign);
if (l->normal_exp > r->normal_exp
- || (l->normal_exp == r->normal_exp &&
- l->fraction > r->fraction))
+ || (l->normal_exp == r->normal_exp
+ && l->fraction > r->fraction))
{
/* |l| > |r| */
if (l->sign)
* If (2) is false, then q = q ; otherwise q = q + 2 .
* i+1 i i+1 i
*
- * With some algebric manipulation, it is not difficult to see
+ * With some algebraic manipulation, it is not difficult to see
* that (2) is equivalent to
* -(i+1)
* s + 2 <= y (3)
* sqrt(+-0) = +-0 ... exact
* sqrt(inf) = inf
* sqrt(-ve) = NaN ... with invalid signal
- * sqrt(NaN) = NaN ... with invalid signal for signaling NaN
+ * sqrt(NaN) = NaN ... with invalid signal for signalling NaN
*
* Other methods : see the appended file at the end of the program below.
*---------------
*/
{
- /* generate sqrt(x) bit by bit */
+ /* Generate sqrt(x) bit by bit. */
unsigned64 y;
unsigned64 q;
unsigned64 s;
y = r->fraction;
f->normal_exp = (r->normal_exp >> 1); /* exp = [exp/2] */
- /* odd exp, double x to make it even */
+ /* Odd exp, double x to make it even. */
ASSERT (y >= IMPLICIT_1 && y < IMPLICIT_4);
if ((r->normal_exp & 1))
{
f->fraction = q;
if (y != 0)
{
- f->fraction |= 1; /* stick remaining bits */
+ f->fraction |= 1; /* Stick remaining bits. */
return sim_fpu_status_inexact;
}
else
case sim_fpu_status_invalid_sqrt:
print (arg, "%sSQRT", prefix);
break;
+ case sim_fpu_status_invalid_irx:
+ print (arg, "%sIRX", prefix);
+ break;
case sim_fpu_status_inexact:
print (arg, "%sX", prefix);
break;
projects / deliverable / binutils-gdb.git / blobdiff