/* real.c - implementation of REAL_ARITHMETIC, REAL_VALUE_ATOF,
and support for XFmode IEEE extended real floating point arithmetic.
- Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
+ Copyright (C) 1993, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
Contributed by Stephen L. Moshier (moshier@world.std.com).
This file is part of GNU CC.
Boston, MA 02111-1307, USA. */
#include "config.h"
-#include <stdio.h>
-#include <errno.h>
+#include "system.h"
#include "tree.h"
-
-#ifndef errno
-extern int errno;
-#endif
+#include "toplev.h"
/* To enable support of XFmode extended real floating point, define
LONG_DOUBLE_TYPE_SIZE 96 in the tm.h file (m68k.h or i386.h).
netlib.att.com: netlib/cephes. */
\f
/* Type of computer arithmetic.
- Only one of DEC, IBM, IEEE, or UNK should get defined.
+ Only one of DEC, IBM, IEEE, C4X, or UNK should get defined.
`IEEE', when REAL_WORDS_BIG_ENDIAN is non-zero, refers generically
to big-endian IEEE floating-point data structure. This definition
no type wider than DFmode. The IBM conversions were contributed by
frank@atom.ansto.gov.au (Frank Crawford).
+ `C4X' refers specifically to the floating point format used on
+ Texas Instruments TMS320C3x and TMS320C4x digital signal
+ processors. This supports QFmode (32-bit float, double) and HFmode
+ (40-bit long double) where BITS_PER_BYTE is 32.
+
If LONG_DOUBLE_TYPE_SIZE = 64 (the default, unless tm.h defines it)
then `long double' and `double' are both implemented, but they
both mean DFmode. In this case, the software floating-point
/* IBM System/370 style */
#define IBM 1
#else /* it's also not an IBM */
+#if TARGET_FLOAT_FORMAT == C4X_FLOAT_FORMAT
+/* TMS320C3x/C4x style */
+#define C4X 1
+#else /* it's also not a C4X */
#if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
#define IEEE
#else /* it's not IEEE either */
unknown arithmetic type
#define UNK 1
#endif /* not IEEE */
+#endif /* not C4X */
#endif /* not IBM */
#endif /* not VAX */
/* Define INFINITY for support of infinity.
Define NANS for support of Not-a-Number's (NaN's). */
-#if !defined(DEC) && !defined(IBM)
+#if !defined(DEC) && !defined(IBM) && !defined(C4X)
#define INFINITY
#define NANS
#endif
#endif /* not REAL_ARITHMETIC */
#endif /* not TFmode */
-#endif /* no XFmode */
+#endif /* not XFmode */
/* Number of 16 bit words in internal format */
enum machine_mode));
static void eclear PROTO((unsigned EMUSHORT *));
static void emov PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
+#if 0
static void eabs PROTO((unsigned EMUSHORT *));
+#endif
static void eneg PROTO((unsigned EMUSHORT *));
static int eisneg PROTO((unsigned EMUSHORT *));
static int eisinf PROTO((unsigned EMUSHORT *));
static void einan PROTO((unsigned EMUSHORT *));
static int eiisnan PROTO((unsigned EMUSHORT *));
static int eiisneg PROTO((unsigned EMUSHORT *));
+#if 0
static void eiinfin PROTO((unsigned EMUSHORT *));
+#endif
static int eiisinf PROTO((unsigned EMUSHORT *));
static int ecmpm PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
static void eshdn1 PROTO((unsigned EMUSHORT *));
static void etoe24 PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
static void toe24 PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
static int ecmp PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
+#if 0
static void eround PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
+#endif
static void ltoe PROTO((HOST_WIDE_INT *, unsigned EMUSHORT *));
static void ultoe PROTO((unsigned HOST_WIDE_INT *, unsigned EMUSHORT *));
static void eifrac PROTO((unsigned EMUSHORT *, HOST_WIDE_INT *,
unsigned EMUSHORT *));
static int eshift PROTO((unsigned EMUSHORT *, int));
static int enormlz PROTO((unsigned EMUSHORT *));
+#if 0
static void e24toasc PROTO((unsigned EMUSHORT *, char *, int));
static void e53toasc PROTO((unsigned EMUSHORT *, char *, int));
static void e64toasc PROTO((unsigned EMUSHORT *, char *, int));
static void e113toasc PROTO((unsigned EMUSHORT *, char *, int));
+#endif /* 0 */
static void etoasc PROTO((unsigned EMUSHORT *, char *, int));
static void asctoe24 PROTO((char *, unsigned EMUSHORT *));
static void asctoe53 PROTO((char *, unsigned EMUSHORT *));
static void toibm PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *,
enum machine_mode));
#endif
+#ifdef C4X
+static void c4xtoe PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *,
+ enum machine_mode));
+static void etoc4x PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *,
+ enum machine_mode));
+static void toc4x PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *,
+ enum machine_mode));
+#endif
static void make_nan PROTO((unsigned EMUSHORT *, int, enum machine_mode));
#if 0
static void uditoe PROTO((unsigned EMUSHORT *, unsigned EMUSHORT *));
{
switch (mode)
{
-
case TFmode:
/* Swap halfwords in the fourth long. */
th = (unsigned long) e[6] & 0xffff;
x[3] = (long) t;
case XFmode:
-
/* Swap halfwords in the third long. */
th = (unsigned long) e[4] & 0xffff;
t = (unsigned long) e[5] & 0xffff;
/* fall into the double case */
case DFmode:
-
- /* swap halfwords in the second word */
+ /* Swap halfwords in the second word. */
th = (unsigned long) e[2] & 0xffff;
t = (unsigned long) e[3] & 0xffff;
t |= th << 16;
x[1] = (long) t;
/* fall into the float case */
- case HFmode:
case SFmode:
-
- /* swap halfwords in the first word */
+ case HFmode:
+ /* Swap halfwords in the first word. */
th = (unsigned long) e[0] & 0xffff;
t = (unsigned long) e[1] & 0xffff;
t |= th << 16;
switch (mode)
{
-
case TFmode:
-
/* Pack the fourth long. */
th = (unsigned long) e[7] & 0xffff;
t = (unsigned long) e[6] & 0xffff;
x[3] = (long) t;
case XFmode:
-
/* Pack the third long.
Each element of the input REAL_VALUE_TYPE array has 16 useful bits
in it. */
/* fall into the double case */
case DFmode:
-
- /* pack the second long */
+ /* Pack the second long */
th = (unsigned long) e[3] & 0xffff;
t = (unsigned long) e[2] & 0xffff;
t |= th << 16;
x[1] = (long) t;
/* fall into the float case */
- case HFmode:
case SFmode:
-
- /* pack the first long */
+ case HFmode:
+ /* Pack the first long */
th = (unsigned long) e[1] & 0xffff;
t = (unsigned long) e[0] & 0xffff;
t |= th << 16;
switch (t)
{
+#ifdef C4X
+ case QFmode:
+ case HFmode:
+ asctoe53 (s, tem);
+ e53toe (tem, e);
+ break;
+#else
case HFmode:
+#endif
+
case SFmode:
asctoe24 (s, tem);
e24toe (tem, e);
break;
+
case DFmode:
asctoe53 (s, tem);
e53toe (tem, e);
break;
+
case XFmode:
asctoe64 (s, tem);
e64toe (tem, e);
break;
+
case TFmode:
asctoe113 (s, tem);
e113toe (tem, e);
break;
+
default:
asctoe (s, e);
}
e53toe (t, t);
break;
- case HFmode:
case SFmode:
+#ifndef C4X
+ case HFmode:
+#endif
etoe24 (e, t);
e24toe (t, t);
break;
+#ifdef C4X
+ case HFmode:
+ case QFmode:
+ etoe53 (e, t);
+ e53toe (t, t);
+ break;
+#endif
+
case SImode:
r = etrunci (arg);
return (r);
e53toe (&d, e) IEEE double precision to e type
e64toe (&d, e) IEEE long double precision to e type
e113toe (&d, e) 128-bit long double precision to e type
+#if 0
eabs (e) absolute value
+#endif
eadd (a, b, c) c = b + a
eclear (e) e = 0
ecmp (a, b) Returns 1 if a > b, 0 if a == b,
emov (a, b) b = a
emul (a, b, c) c = b * a
eneg (e) e = -e
+#if 0
eround (a, b) b = nearest integer value to a
+#endif
esub (a, b, c) c = b - a
+#if 0
e24toasc (&f, str, n) single to ASCII string, n digits after decimal
e53toasc (&d, str, n) double to ASCII string, n digits after decimal
e64toasc (&d, str, n) 80-bit long double to ASCII string
e113toasc (&d, str, n) 128-bit long double to ASCII string
+#endif
etoasc (e, str, n) e to ASCII string, n digits after decimal
etoe24 (e, &f) convert e type to IEEE single precision
etoe53 (e, &d) convert e type to IEEE double precision
eiisnan (ai) 1 if a NaN
eiisneg (ai) 1 if sign bit of ai != 0, else 0
einan (ai) set ai = NaN
+#if 0
eiinfin (ai) set ai = infinity
+#endif
The result is always normalized and rounded to NI-4 word precision
after each arithmetic operation.
}
+#if 0
/* Absolute value of e-type X. */
static void
/* sign is top bit of last word of external format */
x[NE - 1] &= 0x7fff;
}
+#endif /* 0 */
/* Negate the e-type number X. */
return x[0] != 0;
}
+#if 0
/* Fill exploded e-type X with infinity pattern.
This has maximum exponent and significand all zeros. */
ecleaz (x);
x[E] = 0x7fff;
}
+#endif /* 0 */
/* Return nonzero if exploded e-type X is infinite. */
re = rw - 1;
rebit = 1;
break;
+
case 113:
rw = 10;
rmsk = 0x7fff;
rebit = 0x8000;
re = rw;
break;
+
case 64:
rw = 7;
rmsk = 0xffff;
re = rw - 1;
rebit = 1;
break;
+
/* For DEC or IBM arithmetic */
case 56:
rw = 6;
rebit = 0x100;
re = rw;
break;
+
case 53:
rw = 6;
rmsk = 0x7ff;
rebit = 0x800;
re = rw;
break;
+
+ /* For C4x arithmetic */
+ case 32:
+ rw = 5;
+ rmsk = 0xffff;
+ rmbit = 0x8000;
+ rebit = 1;
+ re = rw - 1;
+ break;
+
case 24:
rw = 4;
rmsk = 0xff;
ibmtoe (pe, y, DFmode);
#else
+#ifdef C4X
+
+ c4xtoe (pe, y, HFmode);
+
+#else
register unsigned EMUSHORT r;
register unsigned EMUSHORT *e, *p;
unsigned EMUSHORT yy[NI];
#endif
eshift (yy, -5);
if (denorm)
- { /* if zero exponent, then normalize the significand */
+ {
+ /* If zero exponent, then normalize the significand. */
if ((k = enormlz (yy)) > NBITS)
ecleazs (yy);
else
yy[E] -= (unsigned EMUSHORT) (k - 1);
}
emovo (yy, y);
+#endif /* not C4X */
#endif /* not IBM */
#endif /* not DEC */
}
ibmtoe (pe, y, SFmode);
#else
+
+#ifdef C4X
+
+ c4xtoe (pe, y, QFmode);
+
+#else
+
register unsigned EMUSHORT r;
register unsigned EMUSHORT *e, *p;
unsigned EMUSHORT yy[NI];
yy[E] -= (unsigned EMUSHORT) (k - 1);
}
emovo (yy, y);
+#endif /* not C4X */
#endif /* not IBM */
}
toibm (x, y, DFmode);
}
-#else /* it's neither DEC nor IBM */
+#else /* it's neither DEC nor IBM */
+#ifdef C4X
+/* Convert e-type X to C4X-format long double E. */
+
+static void
+etoe53 (x, e)
+ unsigned EMUSHORT *x, *e;
+{
+ etoc4x (x, e, HFmode);
+}
+
+/* Convert exploded e-type X, that has already been rounded to
+ 56-bit precision, to IBM 370 double Y. */
+
+static void
+toe53 (x, y)
+ unsigned EMUSHORT *x, *y;
+{
+ toc4x (x, y, HFmode);
+}
+
+#else /* it's neither DEC nor IBM nor C4X */
/* Convert e-type X to IEEE double E. */
}
}
+#endif /* not C4X */
#endif /* not IBM */
#endif /* not DEC */
}
#else
+
+#ifdef C4X
+/* Convert e-type X to C4X float E. */
+
+static void
+etoe24 (x, e)
+ unsigned EMUSHORT *x, *e;
+{
+ etoc4x (x, e, QFmode);
+}
+
+/* Convert exploded e-type X, that has already been rounded to
+ float precision, to IBM 370 float Y. */
+
+static void
+toe24 (x, y)
+ unsigned EMUSHORT *x, *y;
+{
+ toc4x (x, y, QFmode);
+}
+
+#else
+
/* Convert e-type X to IEEE float E. DEC float is the same as IEEE float. */
static void
}
#endif
}
+#endif /* not C4X */
#endif /* not IBM */
/* Compare two e type numbers.
return (-msign); /* p is littler */
}
+#if 0
/* Find e-type nearest integer to X, as floor (X + 0.5). */
static void
eadd (ehalf, x, y);
efloor (y, y);
}
+#endif /* 0 */
/* Convert HOST_WIDE_INT LP to e type Y. */
};
#endif
+#if 0
/* Convert float value X to ASCII string STRING with NDIG digits after
the decimal point. */
e113toe (x, w);
etoasc (w, string, ndigs);
}
+#endif /* 0 */
/* Convert e-type X to ASCII string STRING with NDIGS digits after
the decimal point. */
#if defined(DEC) || defined(IBM)
asctoeg (s, y, 56);
#else
+#if defined(C4X)
+ asctoeg (s, y, 32);
+#else
asctoeg (s, y, 53);
#endif
+#endif
}
/* Round and convert directly to the destination type */
if (oprec == 53)
lexp -= EXONE - 0x3ff;
+#ifdef C4X
+ else if (oprec == 24 || oprec == 32)
+ lexp -= (EXONE - 0x7f);
+#else
#ifdef IBM
else if (oprec == 24 || oprec == 56)
lexp -= EXONE - (0x41 << 2);
#else
else if (oprec == 24)
lexp -= EXONE - 0177;
-#endif
+#endif /* IBM */
+#endif /* C4X */
#ifdef DEC
else if (oprec == 56)
lexp -= EXONE - 0201;
toibm (yy, y, DFmode);
break;
#endif
+#ifdef C4X
+ case 32:
+ toc4x (yy, y, HFmode);
+ break;
+#endif
+
case 53:
toe53 (yy, y);
break;
}
#endif /* IBM */
+
+#ifdef C4X
+/* Convert C4X single/double precision to e type. */
+
+static void
+c4xtoe (d, e, mode)
+ unsigned EMUSHORT *d;
+ unsigned EMUSHORT *e;
+ enum machine_mode mode;
+{
+ unsigned EMUSHORT y[NI];
+ int r;
+ int rndsav;
+ int isnegative;
+ int size;
+ int i;
+ int carry;
+
+ /* Short-circuit the zero case. */
+ if ((d[0] == 0x8000)
+ && (d[1] == 0x0000)
+ && ((mode == QFmode) || ((d[2] == 0x0000) && (d[3] == 0x0000))))
+ {
+ e[0] = 0;
+ e[1] = 0;
+ e[2] = 0;
+ e[3] = 0;
+ e[4] = 0;
+ e[5] = 0;
+ return;
+ }
+
+ ecleaz (y); /* start with a zero */
+ r = d[0]; /* get sign/exponent part */
+ if (r & (unsigned int) 0x0080)
+ {
+ y[0] = 0xffff; /* fill in our sign */
+ isnegative = TRUE;
+ }
+ else
+ {
+ isnegative = FALSE;
+ }
+
+ r >>= 8; /* Shift exponent word down 8 bits. */
+ if (r & 0x80) /* Make the exponent negative if it is. */
+ {
+ r = r | (~0 & ~0xff);
+ }
+
+ if (isnegative)
+ {
+ /* Now do the high order mantissa. We don't "or" on the high bit
+ because it is 2 (not 1) and is handled a little differently
+ below. */
+ y[M] = d[0] & 0x7f;
+
+ y[M+1] = d[1];
+ if (mode != QFmode) /* There are only 2 words in QFmode. */
+ {
+ y[M+2] = d[2]; /* Fill in the rest of our mantissa. */
+ y[M+3] = d[3];
+ size = 4;
+ }
+ else
+ {
+ size = 2;
+ }
+ eshift(y, -8);
+
+ /* Now do the two's complement on the data. */
+
+ carry = 1; /* Initially add 1 for the two's complement. */
+ for (i=size + M; i > M; i--)
+ {
+ if (carry && (y[i] == 0x0000))
+ {
+ /* We overflowed into the next word, carry is the same. */
+ y[i] = carry ? 0x0000 : 0xffff;
+ }
+ else
+ {
+ /* No overflow, just invert and add carry. */
+ y[i] = ((~y[i]) + carry) & 0xffff;
+ carry = 0;
+ }
+ }
+
+ if (carry)
+ {
+ eshift(y, -1);
+ y[M+1] |= 0x8000;
+ r++;
+ }
+ y[1] = r + EXONE;
+ }
+ else
+ {
+ /* Add our e type exponent offset to form our exponent. */
+ r += EXONE;
+ y[1] = r;
+
+ /* Now do the high order mantissa strip off the exponent and sign
+ bits and add the high 1 bit. */
+ y[M] = d[0] & 0x7f | 0x80;
+
+ y[M+1] = d[1];
+ if (mode != QFmode) /* There are only 2 words in QFmode. */
+ {
+ y[M+2] = d[2]; /* Fill in the rest of our mantissa. */
+ y[M+3] = d[3];
+ }
+ eshift(y, -8);
+ }
+
+ emovo (y, e);
+}
+
+
+/* Convert e type to C4X single/double precision. */
+
+static void
+etoc4x (x, d, mode)
+ unsigned EMUSHORT *x, *d;
+ enum machine_mode mode;
+{
+ unsigned EMUSHORT xi[NI];
+ EMULONG exp;
+ int rndsav;
+
+ emovi (x, xi);
+
+ /* Adjust exponent for offsets. */
+ exp = (EMULONG) xi[E] - (EXONE - 0x7f);
+
+ /* Round off to nearest or even. */
+ rndsav = rndprc;
+ rndprc = mode == QFmode ? 24 : 32;
+ emdnorm (xi, 0, 0, exp, 64);
+ rndprc = rndsav;
+ toc4x (xi, d, mode);
+}
+
+static void
+toc4x (x, y, mode)
+ unsigned EMUSHORT *x, *y;
+ enum machine_mode mode;
+{
+ int i;
+ int r;
+ int v;
+ int carry;
+
+ /* Short-circuit the zero case */
+ if ((x[0] == 0) /* Zero exponent and sign */
+ && (x[1] == 0)
+ && (x[M] == 0) /* The rest is for zero mantissa */
+ && (x[M+1] == 0)
+ /* Only check for double if necessary */
+ && ((mode == QFmode) || ((x[M+2] == 0) && (x[M+3] == 0))))
+ {
+ /* We have a zero. Put it into the output and return. */
+ *y++ = 0x8000;
+ *y++ = 0x0000;
+ if (mode != QFmode)
+ {
+ *y++ = 0x0000;
+ *y++ = 0x0000;
+ }
+ return;
+ }
+
+ *y = 0;
+
+ /* Negative number require a two's complement conversion of the
+ mantissa. */
+ if (x[0])
+ {
+ *y = 0x0080;
+
+ i = ((int) x[1]) - 0x7f;
+
+ /* Now add 1 to the inverted data to do the two's complement. */
+ if (mode != QFmode)
+ v = 4 + M;
+ else
+ v = 2 + M;
+ carry = 1;
+ while (v > M)
+ {
+ if (x[v] == 0x0000)
+ {
+ x[v] = carry ? 0x0000 : 0xffff;
+ }
+ else
+ {
+ x[v] = ((~x[v]) + carry) & 0xffff;
+ carry = 0;
+ }
+ v--;
+ }
+
+ /* The following is a special case. The C4X negative float requires
+ a zero in the high bit (because the format is (2 - x) x 2^m), so
+ if a one is in that bit, we have to shift left one to get rid
+ of it. This only occurs if the number is -1 x 2^m. */
+ if (x[M+1] & 0x8000)
+ {
+ /* This is the case of -1 x 2^m, we have to rid ourselves of the
+ high sign bit and shift the exponent. */
+ eshift(x, 1);
+ i--;
+ }
+ }
+ else
+ {
+ i = ((int) x[1]) - 0x7f;
+ }
+
+ if ((i < -128) || (i > 127))
+ {
+ y[0] |= 0xff7f;
+ y[1] = 0xffff;
+ if (mode != QFmode)
+ {
+ y[2] = 0xffff;
+ y[3] = 0xffff;
+ }
+#ifdef ERANGE
+ errno = ERANGE;
+#endif
+ return;
+ }
+
+ y[0] |= ((i & 0xff) << 8);
+
+ eshift (x, 8);
+
+ y[0] |= x[M] & 0x7f;
+ y[1] = x[M + 1];
+ if (mode != QFmode)
+ {
+ y[2] = x[M + 2];
+ y[3] = x[M + 3];
+ }
+}
+#endif /* C4X */
+
/* Output a binary NaN bit pattern in the target machine's format. */
/* If special NaN bit patterns are required, define them in tm.h
{
/* Possibly the `reserved operand' patterns on a VAX can be
used like NaN's, but probably not in the same way as IEEE. */
-#if !defined(DEC) && !defined(IBM)
+#if !defined(DEC) && !defined(IBM) && !defined(C4X)
case TFmode:
n = 8;
if (REAL_WORDS_BIG_ENDIAN)
else
p = TFlittlenan;
break;
+
case XFmode:
n = 6;
if (REAL_WORDS_BIG_ENDIAN)
else
p = XFlittlenan;
break;
+
case DFmode:
n = 4;
if (REAL_WORDS_BIG_ENDIAN)
else
p = DFlittlenan;
break;
- case HFmode:
+
case SFmode:
+ case HFmode:
n = 2;
if (REAL_WORDS_BIG_ENDIAN)
p = SFbignan;
p = SFlittlenan;
break;
#endif
+
default:
abort ();
}
switch (GET_MODE_BITSIZE (mode))
{
case 32:
+
+#if TARGET_FLOAT_FORMAT == C4X_FLOAT_FORMAT
+ return 56;
+#endif
+
return 24;
case 64:
#if TARGET_FLOAT_FORMAT == VAX_FLOAT_FORMAT
return 56;
#else
+#if TARGET_FLOAT_FORMAT == C4X_FLOAT_FORMAT
+ return 56;
+#else
abort ();
#endif
#endif
#endif
+#endif
case 96:
return 64;
OSDN Git Service
