#if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
#define IEEE
#else /* it's not IEEE either */
-/* UNKnown arithmetic. We don't support this and can't go on. */
+/* UNKnown arithmetic. We don't support this and can't go on. */
unknown arithmetic type
#define UNK 1
#endif /* not IEEE */
#define NANS
#endif
-/* Support of NaNs requires support of infinity. */
+/* Support of NaNs requires support of infinity. */
#ifdef NANS
#ifndef INFINITY
#define INFINITY
#endif
\f
/* Find a host integer type that is at least 16 bits wide,
- and another type at least twice whatever that size is. */
+ and another type at least twice whatever that size is. */
#if HOST_BITS_PER_CHAR >= 16
#define EMUSHORT char
#define EMUSHORT_SIZE HOST_BITS_PER_LONG
#define EMULONG_SIZE (2 * HOST_BITS_PER_LONG)
#else
-/* You will have to modify this program to have a smaller unit size. */
+/* You will have to modify this program to have a smaller unit size. */
#define EMU_NON_COMPILE
#endif
#endif
#if HOST_BITS_PER_LONG_LONG >= EMULONG_SIZE
#define EMULONG long long int
#else
-/* You will have to modify this program to have a smaller unit size. */
+/* You will have to modify this program to have a smaller unit size. */
#define EMU_NON_COMPILE
#endif
#endif
#endif
-/* The host interface doesn't work if no 16-bit size exists. */
+/* The host interface doesn't work if no 16-bit size exists. */
#if EMUSHORT_SIZE != 16
#define EMU_NON_COMPILE
#endif
-/* OK to continue compilation. */
+/* OK to continue compilation. */
#ifndef EMU_NON_COMPILE
/* Construct macros to translate between REAL_VALUE_TYPE and e type.
#define MINDECEXP -4956
#ifdef REAL_ARITHMETIC
/* Emulator uses target format internally
- but host stores it in host endian-ness. */
+ but host stores it in host endian-ness. */
#define GET_REAL(r,e) \
do { \
if (HOST_FLOAT_WORDS_BIG_ENDIAN == REAL_WORDS_BIG_ENDIAN) \
- e53toe ((unsigned EMUSHORT*) (r), (e)); \
+ e53toe ((unsigned EMUSHORT *) (r), (e)); \
else \
{ \
unsigned EMUSHORT w[4]; \
{
case TFmode:
- /* Swap halfwords in the fourth long. */
+ /* Swap halfwords in the fourth long. */
th = (unsigned long) e[6] & 0xffff;
t = (unsigned long) e[7] & 0xffff;
t |= th << 16;
case XFmode:
- /* Swap halfwords in the third long. */
+ /* Swap halfwords in the third long. */
th = (unsigned long) e[4] & 0xffff;
t = (unsigned long) e[5] & 0xffff;
t |= th << 16;
}
else
{
- /* Pack the output array without swapping. */
+ /* Pack the output array without swapping. */
switch (mode)
{
case TFmode:
- /* Pack the fourth long. */
+ /* Pack the fourth long. */
th = (unsigned long) e[7] & 0xffff;
t = (unsigned long) e[6] & 0xffff;
t |= th << 16;
GET_REAL (r1, d1);
GET_REAL (r2, d2);
#ifdef NANS
-/* Return NaN input back to the caller. */
+/* Return NaN input back to the caller. */
if (eisnan (d1))
{
PUT_REAL (d1, value);
#ifdef REAL_ARITHMETIC
-/* Check for infinity in a REAL_VALUE_TYPE. */
+/* Check for infinity in a REAL_VALUE_TYPE. */
int
target_isinf (x)
#endif
}
-/* Check whether a REAL_VALUE_TYPE item is a NaN. */
+/* Check whether a REAL_VALUE_TYPE item is a NaN. */
int
target_isnan (x)
/* Check for a negative REAL_VALUE_TYPE number.
- This just checks the sign bit, so that -0 counts as negative. */
+ This just checks the sign bit, so that -0 counts as negative. */
int
target_negative (x)
return (r);
}
+/* Try to change R into its exact multiplicative inverse in machine mode
+ MODE. Return nonzero function value if successful. */
+
+int
+exact_real_inverse (mode, r)
+ enum machine_mode mode;
+ REAL_VALUE_TYPE *r;
+{
+ unsigned EMUSHORT e[NE], einv[NE];
+ REAL_VALUE_TYPE rinv;
+ int i;
+
+ GET_REAL (r, e);
+
+ /* Test for input in range. Don't transform IEEE special values. */
+ if (eisinf (e) || eisnan (e) || (ecmp (e, ezero) == 0))
+ return 0;
+
+ /* Test for a power of 2: all significand bits zero except the MSB.
+ We are assuming the target has binary (or hex) arithmetic. */
+ if (e[NE - 2] != 0x8000)
+ return 0;
+
+ for (i = 0; i < NE - 2; i++)
+ {
+ if (e[i] != 0)
+ return 0;
+ }
+
+ /* Compute the inverse and truncate it to the required mode. */
+ ediv (e, eone, einv);
+ PUT_REAL (einv, &rinv);
+ rinv = real_value_truncate (mode, rinv);
+
+#ifdef CHECK_FLOAT_VALUE
+ /* This check is not redundant. It may, for example, flush
+ a supposedly IEEE denormal value to zero. */
+ i = 0;
+ if (CHECK_FLOAT_VALUE (mode, rinv, i))
+ return 0;
+#endif
+ GET_REAL (&rinv, einv);
+
+ /* Check the bits again, because the truncation might have
+ generated an arbitrary saturation value on overflow. */
+ if (einv[NE - 2] != 0x8000)
+ return 0;
+
+ for (i = 0; i < NE - 2; i++)
+ {
+ if (einv[i] != 0)
+ return 0;
+ }
+
+ /* Fail if the computed inverse is out of range. */
+ if (eisinf (einv) || eisnan (einv) || (ecmp (einv, ezero) == 0))
+ return 0;
+
+ /* Output the reciprocal and return success flag. */
+ PUT_REAL (einv, r);
+ return 1;
+}
#endif /* REAL_ARITHMETIC defined */
/* Used for debugging--print the value of R in human-readable format
ensure that these values are correct for your computer.
For ANSI C compatibility, define ANSIC equal to 1. Currently
- this affects only the atan2 function and others that use it. */
+ this affects only the atan2 function and others that use it. */
/* Constant definitions for math error conditions. */
/* NaN has maximum exponent */
if ((x[NE - 1] & 0x7fff) != 0x7fff)
return (0);
- /* ... and non-zero significand field. */
+ /* ... and non-zero significand field. */
for (i = 0; i < NE - 1; i++)
{
if (*x++ != 0)
}
/* Fill e-type number X with infinity pattern (IEEE)
- or largest possible number (non-IEEE). */
+ or largest possible number (non-IEEE). */
static void
einfin (x)
*xi++ = 0;
}
-/* Clear out exploded e-type XI, but don't touch the sign. */
+/* Clear out exploded e-type XI, but don't touch the sign. */
static void
ecleazs (xi)
x[M + 1] = 0xc000;
}
-/* Return nonzero if exploded e-type X is a NaN. */
+/* Return nonzero if exploded e-type X is a NaN. */
static int
eiisnan (x)
x[E] = 0x7fff;
}
-/* Return nonzero if exploded e-type X is infinite. */
+/* Return nonzero if exploded e-type X is infinite. */
static int
eiisinf (x)
/* Multiply significands */
+
int
emulm (a, b)
unsigned EMUSHORT a[], b[];
/* Radix 65536 versions of multiply and divide. */
/* Multiply significand of e-type number B
- by 16-bit quantity A, return e-type result to C. */
+ by 16-bit quantity A, return e-type result to C. */
static void
m16m (a, b, c)
tdenm = den[M+1];
for (i=M; i<NI; i++)
{
- /* Find trial quotient digit (the radix is 65536). */
+ /* Find trial quotient digit (the radix is 65536). */
tnum = (((unsigned EMULONG) num[M]) << 16) + num[M+1];
- /* Do not execute the divide instruction if it will overflow. */
+ /* Do not execute the divide instruction if it will overflow. */
if ((tdenm * 0xffffL) < tnum)
tquot = 0xffff;
else
tquot = tnum / tdenm;
- /* Multiply denominator by trial quotient digit. */
+ /* Multiply denominator by trial quotient digit. */
m16m ((unsigned int)tquot, den, tprod);
- /* The quotient digit may have been overestimated. */
+ /* The quotient digit may have been overestimated. */
if (ecmpm (tprod, num) > 0)
{
tquot -= 1;
/* Normalize */
j = enormlz (s);
- /* a blank significand could mean either zero or infinity. */
+ /* a blank significand could mean either zero or infinity. */
#ifndef INFINITY
if (j > NBITS)
{
return;
}
}
- /* Round off, unless told not to by rcntrl. */
+ /* Round off, unless told not to by rcntrl. */
if (rcntrl == 0)
goto mdfin;
- /* Set up rounding parameters if the control register changed. */
+ /* Set up rounding parameters if the control register changed. */
if (rndprc != rlast)
{
ecleaz (rbit);
eaddm (rbit, s);
}
mddone:
-/* Undo the temporary shift for denormal values. */
+/* Undo the temporary shift for denormal values. */
if ((exp <= 0) && (rndprc != NBITS)
&& ((rndprc != 64) || ((rndprc == 64) && ! REAL_WORDS_BIG_ENDIAN)))
{
return;
}
/* Infinity minus infinity is a NaN.
- Test for subtracting infinities of the same sign. */
+ Test for subtracting infinities of the same sign. */
if (eisinf (a) && eisinf (b)
&& ((eisneg (a) ^ eisneg (b)) == 0))
{
eadd1 (a, b, c);
}
-/* Add. C = A + B, all e type. */
+/* Add. C = A + B, all e type. */
static void
eadd (a, b, c)
{
#ifdef NANS
-/* NaN plus anything is a NaN. */
+/* NaN plus anything is a NaN. */
if (eisnan (a))
{
emov (a, c);
return;
}
/* Infinity minus infinity is a NaN.
- Test for adding infinities of opposite signs. */
+ Test for adding infinities of opposite signs. */
if (eisinf (a) && eisinf (b)
&& ((eisneg (a) ^ eisneg (b)) != 0))
{
sign = eisneg(a) ^ eisneg(b);
#ifdef NANS
-/* Return any NaN input. */
+/* Return any NaN input. */
if (eisnan (a))
{
emov (a, c);
emov (b, c);
return;
}
-/* Zero over zero, or infinity over infinity, is a NaN. */
+/* Zero over zero, or infinity over infinity, is a NaN. */
if (((ecmp (a, ezero) == 0) && (ecmp (b, ezero) == 0))
|| (eisinf (a) && eisinf (b)))
{
return;
}
#endif
-/* Infinity over anything else is infinity. */
+/* Infinity over anything else is infinity. */
#ifdef INFINITY
if (eisinf (b))
{
einfin (c);
goto divsign;
}
-/* Anything else over infinity is zero. */
+/* Anything else over infinity is zero. */
if (eisinf (a))
{
eclear (c);
lta = ai[E];
ltb = bi[E];
if (bi[E] == 0)
- { /* See if numerator is zero. */
+ { /* See if numerator is zero. */
for (i = 1; i < NI - 1; i++)
{
if (bi[i] != 0)
sign = eisneg(a) ^ eisneg(b);
#ifdef NANS
-/* NaN times anything is the same NaN. */
+/* NaN times anything is the same NaN. */
if (eisnan (a))
{
emov (a, c);
emov (b, c);
return;
}
-/* Zero times infinity is a NaN. */
+/* Zero times infinity is a NaN. */
if ((eisinf (a) && (ecmp (b, ezero) == 0))
|| (eisinf (b) && (ecmp (a, ezero) == 0)))
{
return;
}
#endif
-/* Infinity times anything else is infinity. */
+/* Infinity times anything else is infinity. */
#ifdef INFINITY
if (eisinf (a) || eisinf (b))
{
#endif /* INFINITY */
r >>= 4;
/* If zero exponent, then the significand is denormalized.
- So take back the understood high significand bit. */
+ So take back the understood high significand bit. */
if (r == 0)
{
p = yy;
for (i = 0; i < NE - 5; i++)
*p++ = 0;
-/* This precision is not ordinarily supported on DEC or IBM. */
+/* This precision is not ordinarily supported on DEC or IBM. */
#ifdef DEC
for (i = 0; i < 5; i++)
*p++ = *e++;
*p++ = *e++;
}
#endif
-/* If denormal, remove the implied bit; else shift down 1. */
+/* If denormal, remove the implied bit; else shift down 1. */
if (r == 0)
{
yy[M] = 0;
#endif /* INFINITY */
r >>= 7;
/* If zero exponent, then the significand is denormalized.
- So take back the understood high significand bit. */
+ So take back the understood high significand bit. */
if (r == 0)
{
denorm = 1;
else
q = b + 7; /* point to output exponent */
- /* If not denormal, delete the implied bit. */
+ /* If not denormal, delete the implied bit. */
if (a[E] != 0)
{
eshup1 (a);
i = *p++;
if (i >= (unsigned int) 2047)
- { /* Saturate at largest number less than infinity. */
+ {
+ /* Saturate at largest number less than infinity. */
#ifdef INFINITY
*y |= 0x7ff0;
if (! REAL_WORDS_BIG_ENDIAN)
*y = 0x8000; /* output sign bit */
i = *p++;
-/* Handle overflow cases. */
+/* Handle overflow cases. */
if (i >= 255)
{
#ifdef INFINITY
*i = (HOST_WIDE_INT) xi[M] & 0xffff;
}
- if (xi[0]) /* A negative value yields unsigned integer 0. */
+ if (xi[0]) /* A negative value yields unsigned integer 0. */
*i = 0L;
xi[0] = 0;
}
tnzro:
- /* Test for infinity. */
+ /* Test for infinity. */
if (y[NE - 1] == 0x7fff)
{
if (sign)
if (i < 0)
{ /* Number is greater than 1 */
- /* Convert significand to an integer and strip trailing decimal zeros. */
+ /* Convert significand to an integer and strip trailing decimal zeros. */
emov (y, u);
u[NE - 1] = EXONE + NBITS - 1;
emov (eone, t);
m = MAXP;
p = &etens[0][0];
- /* An unordered compare result shouldn't happen here. */
+ /* An unordered compare result shouldn't happen here. */
while (ecmp (ten, u) <= 0)
{
if (ecmp (p, u) <= 0)
}
else
{ /* Number is less than 1.0 */
- /* Pad significand with trailing decimal zeros. */
+ /* Pad significand with trailing decimal zeros. */
if (y[NE - 1] == 0)
{
while ((y[NE - 2] & 0x8000) == 0)
ediv (t, eone, t);
}
isone:
- /* Find the first (leading) digit. */
+ /* Find the first (leading) digit. */
emovi (t, w);
emovz (w, t);
emovi (y, w);
*s++ = '-';
else
*s++ = ' ';
- /* Examine number of digits requested by caller. */
+ /* Examine number of digits requested by caller. */
if (ndigs < 0)
ndigs = 0;
if (ndigs > NDEC)
*s++ = (char)digit + '0';
*s++ = '.';
}
- /* Generate digits after the decimal point. */
+ /* Generate digits after the decimal point. */
for (k = 0; k <= ndigs; k++)
{
/* multiply current number by 10, without normalizing */
/* round off the ASCII string */
if (digit > 4)
{
- /* Test for critical rounding case in ASCII output. */
+ /* Test for critical rounding case in ASCII output. */
if (digit == 5)
{
emovo (y, t);
}
/* Convert ASCII string SS to e type Y, with a specified rounding precision
- of OPREC bits. */
+ of OPREC bits. */
static void
asctoeg (ss, y, oprec)
unsigned EMUSHORT nsign, *p;
char *sp, *s, *lstr;
- /* Copy the input string. */
+ /* Copy the input string. */
lstr = (char *) alloca (strlen (ss) + 1);
s = ss;
while (*s == ' ') /* skip leading spaces */
/* Ignore leading zeros */
if ((prec == 0) && (decflg == 0) && (k == 0))
goto donchr;
- /* Identify and strip trailing zeros after the decimal point. */
+ /* Identify and strip trailing zeros after the decimal point. */
if ((trail == 0) && (decflg != 0))
{
sp = s;
daldone:
nexp = exp - nexp;
- /* Pad trailing zeros to minimize power of 10, per IEEE spec. */
+ /* Pad trailing zeros to minimize power of 10, per IEEE spec. */
while ((nexp > 0) && (yy[2] == 0))
{
emovz (yy, xt);
esign = -1;
if (nexp > 4096)
{
- /* Punt. Can't handle this without 2 divides. */
+ /* Punt. Can't handle this without 2 divides. */
emovi (etens[0], tt);
lexp -= tt[E];
k = edivm (tt, yy);
/* If special NaN bit patterns are required, define them in tm.h
as arrays of unsigned 16-bit shorts. Otherwise, use the default
- patterns here. */
+ patterns here. */
#ifdef TFMODE_NAN
TFMODE_NAN;
#else
switch (mode)
{
/* Possibly the `reserved operand' patterns on a VAX can be
- used like NaN's, but probably not in the same way as IEEE. */
+ used like NaN's, but probably not in the same way as IEEE. */
#if !defined(DEC) && !defined(IBM)
case TFmode:
n = 8;
s[0] = (unsigned EMUSHORT) f;
s[1] = (unsigned EMUSHORT) (f >> 16);
}
- /* Convert and promote the target float to E-type. */
+ /* Convert and promote the target float to E-type. */
e24toe (s, e);
- /* Output E-type to REAL_VALUE_TYPE. */
+ /* Output E-type to REAL_VALUE_TYPE. */
PUT_REAL (e, &r);
return r;
}
s[3] = (unsigned EMUSHORT) (d[0] >> 48);
#endif
}
- /* Convert target double to E-type. */
+ /* Convert target double to E-type. */
e53toe (s, e);
- /* Output E-type to REAL_VALUE_TYPE. */
+ /* Output E-type to REAL_VALUE_TYPE. */
PUT_REAL (e, &r);
return r;
}
static void
uditoe (di, e)
- unsigned EMUSHORT *di; /* Address of the 64-bit int. */
+ unsigned EMUSHORT *di; /* Address of the 64-bit int. */
unsigned EMUSHORT *e;
{
unsigned EMUSHORT yi[NI];
emovo (yi, e);
}
-/* Convert target computer signed 64-bit integer to e-type. */
+/* Convert target computer signed 64-bit integer to e-type. */
static void
ditoe (di, e)
- unsigned EMUSHORT *di; /* Address of the 64-bit int. */
+ unsigned EMUSHORT *di; /* Address of the 64-bit int. */
unsigned EMUSHORT *e;
{
unsigned EMULONG acc;
}
-/* Convert e-type to unsigned 64-bit int. */
+/* Convert e-type to unsigned 64-bit int. */
static void
etoudi (x, i)
}
-/* Convert e-type to signed 64-bit int. */
+/* Convert e-type to signed 64-bit int. */
static void
etodi (x, i)
}
-/* Longhand square root routine. */
+/* Longhand square root routine. */
static int esqinited = 0;
return;
}
#endif
- /* Bring in the arg and renormalize if it is denormal. */
+ /* Bring in the arg and renormalize if it is denormal. */
emovi (x, xx);
m = (EMULONG) xx[1]; /* local long word exponent */
if (m == 0)
/* bring in next word of arg */
if (j < NE)
num[NI - 1] = xx[j + 3];
- /* Do additional bit on last outer loop, for roundoff. */
+ /* Do additional bit on last outer loop, for roundoff. */
if (nlups <= 8)
n = nlups + 1;
for (i = 0; i < n; i++)
j += 1;
}
- /* Adjust for extra, roundoff loop done. */
+ /* Adjust for extra, roundoff loop done. */
exp += (NBITS - 1) - rndprc;
- /* Sticky bit = 1 if the remainder is nonzero. */
+ /* Sticky bit = 1 if the remainder is nonzero. */
k = 0;
for (i = 3; i < NI; i++)
k |= (int) num[i];
- /* Renormalize and round off. */
+ /* Renormalize and round off. */
emdnorm (sq, k, 0, exp, 64);
emovo (sq, y);
}
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