/* real.c - software floating point emulation.
Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
+ 2000, 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
Contributed by Stephen L. Moshier (moshier@world.std.com).
Re-written by Richard Henderson <rth@redhat.com>
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
- Software Foundation, 59 Temple Place - Suite 330, Boston, MA
- 02111-1307, USA. */
+ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "toplev.h"
#include "real.h"
#include "tm_p.h"
+#include "dfp.h"
/* The floating point model used internally is not exactly IEEE 754
compliant, and close to the description in the ISO C99 standard,
have guard digits or rounding, the computation of 10**exp can
accumulate more than a few digits of error. The previous incarnation
of real.c successfully used a 144-bit fraction; given the current
- layout of REAL_VALUE_TYPE we're forced to expand to at least 160 bits.
-
- Target floating point models that use base 16 instead of base 2
- (i.e. IBM 370), are handled during round_for_format, in which we
- canonicalize the exponent to be a multiple of 4 (log2(16)), and
- adjust the significand to match. */
+ layout of REAL_VALUE_TYPE we're forced to expand to at least 160 bits. */
/* Used to classify two numbers simultaneously. */
int shift = 0, exp;
int i, j;
+ if (r->decimal)
+ return;
+
/* Find the first word that is nonzero. */
for (i = SIGSZ - 1; i >= 0; i--)
if (r->sig[i] == 0)
break;
default:
- abort ();
+ gcc_unreachable ();
}
/* Swap the arguments such that A has the larger exponent. */
r->cl = rvc_normal;
r->sign = sign;
SET_REAL_EXP (r, exp);
+ /* Zero out the remaining fields. */
+ r->signalling = 0;
+ r->canonical = 0;
+ r->decimal = 0;
/* Re-normalize the result. */
normalize (r);
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (r == a || r == b)
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (r == a || r == b)
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (a->sign != b->sign)
return -a->sign - -b->sign;
+ if (a->decimal || b->decimal)
+ return decimal_do_compare (a, b, nan_result);
+
if (REAL_EXP (a) > REAL_EXP (b))
ret = 1;
else if (REAL_EXP (a) < REAL_EXP (b))
break;
case rvc_normal:
+ if (r->decimal)
+ {
+ decimal_do_fix_trunc (r, a);
+ return;
+ }
if (REAL_EXP (r) <= 0)
get_zero (r, r->sign);
else if (REAL_EXP (r) < SIGNIFICAND_BITS)
break;
default:
- abort ();
+ gcc_unreachable ();
}
}
/* Perform the binary or unary operation described by CODE.
- For a unary operation, leave OP1 NULL. */
+ For a unary operation, leave OP1 NULL. This function returns
+ true if the result may be inexact due to loss of precision. */
-void
+bool
real_arithmetic (REAL_VALUE_TYPE *r, int icode, const REAL_VALUE_TYPE *op0,
const REAL_VALUE_TYPE *op1)
{
enum tree_code code = icode;
+ if (op0->decimal || (op1 && op1->decimal))
+ return decimal_real_arithmetic (r, icode, op0, op1);
+
switch (code)
{
case PLUS_EXPR:
- do_add (r, op0, op1, 0);
- break;
+ return do_add (r, op0, op1, 0);
case MINUS_EXPR:
- do_add (r, op0, op1, 1);
- break;
+ return do_add (r, op0, op1, 1);
case MULT_EXPR:
- do_multiply (r, op0, op1);
- break;
+ return do_multiply (r, op0, op1);
case RDIV_EXPR:
- do_divide (r, op0, op1);
- break;
+ return do_divide (r, op0, op1);
case MIN_EXPR:
if (op1->cl == rvc_nan)
break;
default:
- abort ();
+ gcc_unreachable ();
}
+ return false;
}
/* Legacy. Similar, but return the result directly. */
return do_compare (op0, op1, 0) != 0;
default:
- abort ();
+ gcc_unreachable ();
}
}
case rvc_normal:
return REAL_EXP (r);
default:
- abort ();
+ gcc_unreachable ();
}
}
break;
default:
- abort ();
+ gcc_unreachable ();
}
}
return (r->cl == rvc_nan);
}
+/* Determine whether a floating-point value X is finite. */
+
+bool
+real_isfinite (const REAL_VALUE_TYPE *r)
+{
+ return (r->cl != rvc_nan) && (r->cl != rvc_inf);
+}
+
/* Determine whether a floating-point value X is negative. */
bool
return true;
case rvc_normal:
+ if (a->decimal != b->decimal)
+ return false;
if (REAL_EXP (a) != REAL_EXP (b))
return false;
break;
break;
default:
- abort ();
+ gcc_unreachable ();
}
for (i = 0; i < SIGSZ; ++i)
return i;
case rvc_normal:
+ if (r->decimal)
+ return decimal_real_to_integer (r);
+
if (REAL_EXP (r) <= 0)
goto underflow;
/* Only force overflow for unsigned overflow. Signed overflow is
if (HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG)
i = r->sig[SIGSZ-1];
- else if (HOST_BITS_PER_WIDE_INT == 2*HOST_BITS_PER_LONG)
+ else
{
+ gcc_assert (HOST_BITS_PER_WIDE_INT == 2 * HOST_BITS_PER_LONG);
i = r->sig[SIGSZ-1];
i = i << (HOST_BITS_PER_LONG - 1) << 1;
i |= r->sig[SIGSZ-2];
}
- else
- abort ();
i >>= HOST_BITS_PER_WIDE_INT - REAL_EXP (r);
return i;
default:
- abort ();
+ gcc_unreachable ();
}
}
break;
case rvc_normal:
+ if (r->decimal)
+ {
+ decimal_real_to_integer2 (plow, phigh, r);
+ return;
+ }
+
exp = REAL_EXP (r);
if (exp <= 0)
goto underflow;
high = t.sig[SIGSZ-1];
low = t.sig[SIGSZ-2];
}
- else if (HOST_BITS_PER_WIDE_INT == 2*HOST_BITS_PER_LONG)
+ else
{
+ gcc_assert (HOST_BITS_PER_WIDE_INT == 2*HOST_BITS_PER_LONG);
high = t.sig[SIGSZ-1];
high = high << (HOST_BITS_PER_LONG - 1) << 1;
high |= t.sig[SIGSZ-2];
low = low << (HOST_BITS_PER_LONG - 1) << 1;
low |= t.sig[SIGSZ-4];
}
- else
- abort ();
if (r->sign)
{
break;
default:
- abort ();
+ gcc_unreachable ();
}
*plow = low;
strcpy (str, (r.sign ? "-NaN" : "+NaN"));
return;
default:
- abort ();
+ gcc_unreachable ();
+ }
+
+ if (r.decimal)
+ {
+ decimal_real_to_decimal (str, &r, buf_size, digits, crop_trailing_zeros);
+ return;
}
/* Bound the number of digits printed by the size of the representation. */
/* Bound the number of digits printed by the size of the output buffer. */
max_digits = buf_size - 1 - 1 - 2 - max_digits - 1;
- if (max_digits > buf_size)
- abort ();
+ gcc_assert (max_digits <= buf_size);
if (digits > max_digits)
digits = max_digits;
do_multiply (&r, &r, ten);
digit = rtd_divmod (&r, &pten);
dec_exp -= 1;
- if (digit == 0)
- abort ();
+ gcc_assert (digit != 0);
}
/* ... or overflow. */
*p++ = '0';
dec_exp += 1;
}
- else if (digit > 10)
- abort ();
else
- *p++ = digit + '0';
+ {
+ gcc_assert (digit <= 10);
+ *p++ = digit + '0';
+ }
/* Generate subsequent digits. */
while (--digits > 0)
strcpy (str, (r->sign ? "-NaN" : "+NaN"));
return;
default:
- abort ();
+ gcc_unreachable ();
+ }
+
+ if (r->decimal)
+ {
+ /* Hexadecimal format for decimal floats is not interesting. */
+ strcpy (str, "N/A");
+ return;
}
if (digits == 0)
sprintf (exp_buf, "p%+d", exp);
max_digits = buf_size - strlen (exp_buf) - r->sign - 4 - 1;
- if (max_digits > buf_size)
- abort ();
+ gcc_assert (max_digits <= buf_size);
if (digits > max_digits)
digits = max_digits;
}
/* Initialize R from a decimal or hexadecimal string. The string is
- assumed to have been syntax checked already. */
+ assumed to have been syntax checked already. Return -1 if the
+ value underflows, +1 if overflows, and 0 otherwise. */
-void
+int
real_from_string (REAL_VALUE_TYPE *r, const char *str)
{
int exp = 0;
|= (unsigned long) d << (pos % HOST_BITS_PER_LONG);
pos -= 4;
}
+ else if (d)
+ /* Ensure correct rounding by setting last bit if there is
+ a subsequent nonzero digit. */
+ r->sig[0] |= 1;
exp += 4;
str++;
}
|= (unsigned long) d << (pos % HOST_BITS_PER_LONG);
pos -= 4;
}
+ else if (d)
+ /* Ensure correct rounding by setting last bit if there is
+ a subsequent nonzero digit. */
+ r->sig[0] |= 1;
str++;
}
}
+
+ /* If the mantissa is zero, ignore the exponent. */
+ if (!cmp_significand_0 (r))
+ goto is_a_zero;
+
if (*str == 'p' || *str == 'P')
{
bool exp_neg = false;
}
}
+ /* If the mantissa is zero, ignore the exponent. */
+ if (r->cl == rvc_zero)
+ goto is_a_zero;
+
if (*str == 'e' || *str == 'E')
{
bool exp_neg = false;
}
r->sign = sign;
- return;
+ return 0;
+
+ is_a_zero:
+ get_zero (r, sign);
+ return 0;
underflow:
get_zero (r, sign);
- return;
+ return -1;
overflow:
get_inf (r, sign);
- return;
+ return 1;
}
/* Legacy. Similar, but return the result directly. */
return r;
}
+/* Initialize R from string S and desired MODE. */
+
+void
+real_from_string3 (REAL_VALUE_TYPE *r, const char *s, enum machine_mode mode)
+{
+ if (DECIMAL_FLOAT_MODE_P (mode))
+ decimal_real_from_string (r, s);
+ else
+ real_from_string (r, s);
+
+ if (mode != VOIDmode)
+ real_convert (r, mode, r);
+}
+
/* Initialize R from the integer pair HIGH+LOW. */
void
get_zero (r, 0);
else
{
+ memset (r, 0, sizeof (*r));
r->cl = rvc_normal;
r->sign = high < 0 && !unsigned_p;
SET_REAL_EXP (r, 2 * HOST_BITS_PER_WIDE_INT);
{
r->sig[SIGSZ-1] = high;
r->sig[SIGSZ-2] = low;
- memset (r->sig, 0, sizeof(long)*(SIGSZ-2));
}
- else if (HOST_BITS_PER_LONG*2 == HOST_BITS_PER_WIDE_INT)
+ else
{
+ gcc_assert (HOST_BITS_PER_LONG*2 == HOST_BITS_PER_WIDE_INT);
r->sig[SIGSZ-1] = high >> (HOST_BITS_PER_LONG - 1) >> 1;
r->sig[SIGSZ-2] = high;
r->sig[SIGSZ-3] = low >> (HOST_BITS_PER_LONG - 1) >> 1;
r->sig[SIGSZ-4] = low;
- if (SIGSZ > 4)
- memset (r->sig, 0, sizeof(long)*(SIGSZ-4));
}
- else
- abort ();
normalize (r);
}
{
static REAL_VALUE_TYPE tens[EXP_BITS];
- if (n < 0 || n >= EXP_BITS)
- abort ();
+ gcc_assert (n >= 0);
+ gcc_assert (n < EXP_BITS);
if (tens[n].cl == rvc_zero)
{
{
static REAL_VALUE_TYPE tens[EXP_BITS];
- if (n < 0 || n >= EXP_BITS)
- abort ();
+ gcc_assert (n >= 0);
+ gcc_assert (n < EXP_BITS);
if (tens[n].cl == rvc_zero)
do_divide (&tens[n], real_digit (1), ten_to_ptwo (n));
{
static REAL_VALUE_TYPE num[10];
- if (n < 0 || n > 9)
- abort ();
+ gcc_assert (n >= 0);
+ gcc_assert (n <= 9);
if (n > 0 && num[n].cl == rvc_zero)
real_from_integer (&num[n], VOIDmode, n, 0, 1);
const struct real_format *fmt;
fmt = REAL_MODE_FORMAT (mode);
- if (fmt == NULL)
- abort ();
+ gcc_assert (fmt);
if (*str == 0)
{
else
{
int base = 10, d;
- bool neg = false;
memset (r, 0, sizeof (*r));
r->cl = rvc_nan;
while (ISSPACE (*str))
str++;
if (*str == '-')
- str++, neg = true;
+ str++;
else if (*str == '+')
str++;
if (*str == '0')
{
- if (*++str == 'x')
- str++, base = 16;
+ str++;
+ if (*str == 'x' || *str == 'X')
+ {
+ base = 16;
+ str++;
+ }
else
base = 8;
}
add_significands (r, r, &u);
break;
default:
- abort ();
+ gcc_unreachable ();
}
get_zero (&u, 0);
int np2;
fmt = REAL_MODE_FORMAT (mode);
- if (fmt == NULL)
- abort ();
+ gcc_assert (fmt);
+ memset (r, 0, sizeof (*r));
+
+ if (fmt->b == 10)
+ decimal_real_maxval (r, sign, mode);
+ else
+ {
+ r->cl = rvc_normal;
+ r->sign = sign;
+ SET_REAL_EXP (r, fmt->emax);
- r->cl = rvc_normal;
- r->sign = sign;
- r->signalling = 0;
- r->canonical = 0;
- SET_REAL_EXP (r, fmt->emax * fmt->log2_b);
+ np2 = SIGNIFICAND_BITS - fmt->p;
+ memset (r->sig, -1, SIGSZ * sizeof (unsigned long));
+ clear_significand_below (r, np2);
- np2 = SIGNIFICAND_BITS - fmt->p * fmt->log2_b;
- memset (r->sig, -1, SIGSZ * sizeof (unsigned long));
- clear_significand_below (r, np2);
+ if (fmt->pnan < fmt->p)
+ /* This is an IBM extended double format made up of two IEEE
+ doubles. The value of the long double is the sum of the
+ values of the two parts. The most significant part is
+ required to be the value of the long double rounded to the
+ nearest double. Rounding means we need a slightly smaller
+ value for LDBL_MAX. */
+ clear_significand_bit (r, SIGNIFICAND_BITS - fmt->pnan);
+ }
}
/* Fills R with 2**N. */
bool guard, lsb;
int emin2m1, emax2;
- p2 = fmt->p * fmt->log2_b;
- emin2m1 = (fmt->emin - 1) * fmt->log2_b;
- emax2 = fmt->emax * fmt->log2_b;
+ if (r->decimal)
+ {
+ if (fmt->b == 10)
+ {
+ decimal_round_for_format (fmt, r);
+ return;
+ }
+ /* FIXME. We can come here via fp_easy_constant
+ (e.g. -O0 on '_Decimal32 x = 1.0 + 2.0dd'), but have not
+ investigated whether this convert needs to be here, or
+ something else is missing. */
+ decimal_real_convert (r, DFmode, r);
+ }
+
+ p2 = fmt->p;
+ emin2m1 = fmt->emin - 1;
+ emax2 = fmt->emax;
np2 = SIGNIFICAND_BITS - p2;
switch (r->cl)
break;
default:
- abort ();
- }
-
- /* If we're not base2, normalize the exponent to a multiple of
- the true base. */
- if (fmt->log2_b != 1)
- {
- int shift = REAL_EXP (r) & (fmt->log2_b - 1);
- if (shift)
- {
- shift = fmt->log2_b - shift;
- r->sig[0] |= sticky_rshift_significand (r, r, shift);
- SET_REAL_EXP (r, REAL_EXP (r) + shift);
- }
+ gcc_unreachable ();
}
/* Check the range of the exponent. If we're out of range,
if (REAL_EXP (r) > emax2)
goto overflow;
r->sig[SIGSZ-1] = SIG_MSB;
-
- if (fmt->log2_b != 1)
- {
- int shift = REAL_EXP (r) & (fmt->log2_b - 1);
- if (shift)
- {
- shift = fmt->log2_b - shift;
- rshift_significand (r, r, shift);
- SET_REAL_EXP (r, REAL_EXP (r) + shift);
- if (REAL_EXP (r) > emax2)
- goto overflow;
- }
- }
}
}
const struct real_format *fmt;
fmt = REAL_MODE_FORMAT (mode);
- if (fmt == NULL)
- abort ();
+ gcc_assert (fmt);
*r = *a;
+
+ if (a->decimal || fmt->b == 10)
+ decimal_real_convert (r, mode, a);
+
round_for_format (fmt, r);
/* round_for_format de-normalizes denormals. Undo just that part. */
bool
exact_real_truncate (enum machine_mode mode, const REAL_VALUE_TYPE *a)
{
+ const struct real_format *fmt;
REAL_VALUE_TYPE t;
+ int emin2m1;
+
+ fmt = REAL_MODE_FORMAT (mode);
+ gcc_assert (fmt);
+
+ /* Don't allow conversion to denormals. */
+ emin2m1 = fmt->emin - 1;
+ if (REAL_EXP (a) <= emin2m1)
+ return false;
+
+ /* After conversion to the new mode, the value must be identical. */
real_convert (&t, mode, a);
return real_identical (&t, a);
}
const struct real_format *fmt;
fmt = REAL_MODE_FORMAT (mode);
- if (fmt == NULL)
- abort ();
+ gcc_assert (fmt);
return real_to_target_fmt (buf, r, fmt);
}
const struct real_format *fmt;
fmt = REAL_MODE_FORMAT (mode);
- if (fmt == NULL)
- abort ();
+ gcc_assert (fmt);
(*fmt->decode) (fmt, r, buf);
}
-/* Return the number of bits in the significand for MODE. */
+/* Return the number of bits of the largest binary value that the
+ significand of MODE will hold. */
/* ??? Legacy. Should get access to real_format directly. */
int
if (fmt == NULL)
return 0;
- return fmt->p * fmt->log2_b;
+ if (fmt->b == 10)
+ {
+ /* Return the size in bits of the largest binary value that can be
+ held by the decimal coefficient for this mode. This is one more
+ than the number of bits required to hold the largest coefficient
+ of this mode. */
+ double log2_10 = 3.3219281;
+ return fmt->p * log2_10;
+ }
+ return fmt->p;
}
/* Return a hash value for the given real value. */
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (sizeof(unsigned long) > sizeof(unsigned int))
if (fmt->has_nans)
{
if (r->canonical)
- sig = 0;
+ sig = (fmt->canonical_nan_lsbs_set ? (1 << 22) - 1 : 0);
if (r->signalling == fmt->qnan_msb_set)
sig &= ~(1 << 22);
else
sig |= 1 << 22;
- /* We overload qnan_msb_set here: it's only clear for
- mips_ieee_single, which wants all mantissa bits but the
- quiet/signalling one set in canonical NaNs (at least
- Quiet ones). */
- if (r->canonical && !fmt->qnan_msb_set)
- sig |= (1 << 22) - 1;
- else if (sig == 0)
+ if (sig == 0)
sig = 1 << 21;
image |= 255 << 23;
break;
default:
- abort ();
+ gcc_unreachable ();
}
buf[0] = image;
encode_ieee_single,
decode_ieee_single,
2,
- 1,
24,
24,
-125,
128,
31,
+ 31,
true,
true,
true,
true,
- true
+ true,
+ false
};
const struct real_format mips_single_format =
encode_ieee_single,
decode_ieee_single,
2,
- 1,
24,
24,
-125,
128,
31,
+ 31,
true,
true,
true,
true,
- false
+ false,
+ true
};
+const struct real_format motorola_single_format =
+ {
+ encode_ieee_single,
+ decode_ieee_single,
+ 2,
+ 24,
+ 24,
+ -125,
+ 128,
+ 31,
+ 31,
+ true,
+ true,
+ true,
+ true,
+ true,
+ true
+ };
\f
/* IEEE double-precision format. */
if (fmt->has_nans)
{
if (r->canonical)
- sig_hi = sig_lo = 0;
+ {
+ if (fmt->canonical_nan_lsbs_set)
+ {
+ sig_hi = (1 << 19) - 1;
+ sig_lo = 0xffffffff;
+ }
+ else
+ {
+ sig_hi = 0;
+ sig_lo = 0;
+ }
+ }
if (r->signalling == fmt->qnan_msb_set)
sig_hi &= ~(1 << 19);
else
sig_hi |= 1 << 19;
- /* We overload qnan_msb_set here: it's only clear for
- mips_ieee_single, which wants all mantissa bits but the
- quiet/signalling one set in canonical NaNs (at least
- Quiet ones). */
- if (r->canonical && !fmt->qnan_msb_set)
- {
- sig_hi |= (1 << 19) - 1;
- sig_lo = 0xffffffff;
- }
- else if (sig_hi == 0 && sig_lo == 0)
+ if (sig_hi == 0 && sig_lo == 0)
sig_hi = 1 << 18;
image_hi |= 2047 << 20;
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (FLOAT_WORDS_BIG_ENDIAN)
encode_ieee_double,
decode_ieee_double,
2,
- 1,
53,
53,
-1021,
1024,
63,
+ 63,
true,
true,
true,
true,
- true
+ true,
+ false
};
const struct real_format mips_double_format =
encode_ieee_double,
decode_ieee_double,
2,
- 1,
53,
53,
-1021,
1024,
63,
+ 63,
true,
true,
true,
true,
- false
+ false,
+ true
};
+const struct real_format motorola_double_format =
+ {
+ encode_ieee_double,
+ decode_ieee_double,
+ 2,
+ 53,
+ 53,
+ -1021,
+ 1024,
+ 63,
+ 63,
+ true,
+ true,
+ true,
+ true,
+ true,
+ true
+ };
\f
/* IEEE extended real format. This comes in three flavors: Intel's as
a 12 byte image, Intel's as a 16 byte image, and Motorola's. Intel
if (fmt->has_nans)
{
image_hi |= 32767;
- if (HOST_BITS_PER_LONG == 32)
+ if (r->canonical)
+ {
+ if (fmt->canonical_nan_lsbs_set)
+ {
+ sig_hi = (1 << 30) - 1;
+ sig_lo = 0xffffffff;
+ }
+ }
+ else if (HOST_BITS_PER_LONG == 32)
{
sig_hi = r->sig[SIGSZ-1];
sig_lo = r->sig[SIGSZ-2];
else
{
exp += 16383 - 1;
- if (exp < 0)
- abort ();
+ gcc_assert (exp >= 0);
}
image_hi |= exp;
break;
default:
- abort ();
+ gcc_unreachable ();
}
buf[0] = sig_lo, buf[1] = sig_hi, buf[2] = image_hi;
encode_ieee_extended_motorola,
decode_ieee_extended_motorola,
2,
- 1,
64,
64,
-16382,
16384,
95,
+ 95,
+ true,
true,
true,
true,
encode_ieee_extended_intel_96,
decode_ieee_extended_intel_96,
2,
- 1,
64,
64,
-16381,
16384,
79,
+ 79,
true,
true,
true,
true,
- true
+ true,
+ false
};
const struct real_format ieee_extended_intel_128_format =
encode_ieee_extended_intel_128,
decode_ieee_extended_intel_128,
2,
- 1,
64,
64,
-16381,
16384,
79,
+ 79,
true,
true,
true,
true,
- true
+ true,
+ false
};
/* The following caters to i386 systems that set the rounding precision
encode_ieee_extended_intel_96,
decode_ieee_extended_intel_96,
2,
- 1,
53,
53,
-16381,
16384,
79,
+ 79,
true,
true,
true,
true,
- true
+ true,
+ false
};
\f
/* IBM 128-bit extended precision format: a pair of IEEE double precision
range as an IEEE double precision value, but effectively 106 bits of
significand precision. Infinity and NaN are represented by their IEEE
double precision value stored in the first number, the second number is
- ignored. Zeroes, Infinities, and NaNs are set in both doubles
- due to precedent. */
+ +0.0 or -0.0 for Infinity and don't-care for NaN. */
static void encode_ibm_extended (const struct real_format *fmt,
long *, const REAL_VALUE_TYPE *);
encode_ibm_extended,
decode_ibm_extended,
2,
- 1,
53 + 53,
53,
-1021 + 53,
1024,
+ 127,
-1,
true,
true,
true,
true,
- true
+ true,
+ false
};
const struct real_format mips_extended_format =
encode_ibm_extended,
decode_ibm_extended,
2,
- 1,
53 + 53,
53,
-1021 + 53,
1024,
+ 127,
-1,
true,
true,
true,
true,
- false
+ false,
+ true
};
\f
if (r->canonical)
{
- /* Don't use bits from the significand. The
- initialization above is right. */
+ if (fmt->canonical_nan_lsbs_set)
+ {
+ image3 |= 0x7fff;
+ image2 = image1 = image0 = 0xffffffff;
+ }
}
else if (HOST_BITS_PER_LONG == 32)
{
image3 &= ~0x8000;
else
image3 |= 0x8000;
- /* We overload qnan_msb_set here: it's only clear for
- mips_ieee_single, which wants all mantissa bits but the
- quiet/signalling one set in canonical NaNs (at least
- Quiet ones). */
- if (r->canonical && !fmt->qnan_msb_set)
- {
- image3 |= 0x7fff;
- image2 = image1 = image0 = 0xffffffff;
- }
- else if (((image3 & 0xffff) | image2 | image1 | image0) == 0)
+ if (((image3 & 0xffff) | image2 | image1 | image0) == 0)
image3 |= 0x4000;
}
else
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (FLOAT_WORDS_BIG_ENDIAN)
encode_ieee_quad,
decode_ieee_quad,
2,
- 1,
113,
113,
-16381,
16384,
127,
+ 127,
true,
true,
true,
true,
- true
+ true,
+ false
};
const struct real_format mips_quad_format =
encode_ieee_quad,
decode_ieee_quad,
2,
- 1,
113,
113,
-16381,
16384,
127,
+ 127,
true,
true,
true,
true,
- false
+ false,
+ true
};
\f
/* Descriptions of VAX floating point formats can be found beginning at
break;
default:
- abort ();
+ gcc_unreachable ();
}
buf[0] = image;
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (FLOAT_WORDS_BIG_ENDIAN)
break;
default:
- abort ();
+ gcc_unreachable ();
}
if (FLOAT_WORDS_BIG_ENDIAN)
encode_vax_f,
decode_vax_f,
2,
- 1,
24,
24,
-127,
127,
15,
+ 15,
+ false,
false,
false,
false,
encode_vax_d,
decode_vax_d,
2,
- 1,
56,
56,
-127,
127,
15,
+ 15,
+ false,
false,
false,
false,
encode_vax_g,
decode_vax_g,
2,
- 1,
53,
53,
-1023,
1023,
15,
+ 15,
+ false,
false,
false,
false,
false
};
\f
-/* A good reference for these can be found in chapter 9 of
- "ESA/390 Principles of Operation", IBM document number SA22-7201-01.
- An on-line version can be found here:
-
- http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DZ9AR001/9.1?DT=19930923083613
-*/
-
-static void encode_i370_single (const struct real_format *fmt,
- long *, const REAL_VALUE_TYPE *);
-static void decode_i370_single (const struct real_format *,
- REAL_VALUE_TYPE *, const long *);
-static void encode_i370_double (const struct real_format *fmt,
- long *, const REAL_VALUE_TYPE *);
-static void decode_i370_double (const struct real_format *,
- REAL_VALUE_TYPE *, const long *);
-
+/* Encode real R into a single precision DFP value in BUF. */
static void
-encode_i370_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
- long *buf, const REAL_VALUE_TYPE *r)
+encode_decimal_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
+ long *buf ATTRIBUTE_UNUSED,
+ const REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED)
{
- unsigned long sign, exp, sig, image;
-
- sign = r->sign << 31;
-
- switch (r->cl)
- {
- case rvc_zero:
- image = 0;
- break;
-
- case rvc_inf:
- case rvc_nan:
- image = 0x7fffffff | sign;
- break;
-
- case rvc_normal:
- sig = (r->sig[SIGSZ-1] >> (HOST_BITS_PER_LONG - 24)) & 0xffffff;
- exp = ((REAL_EXP (r) / 4) + 64) << 24;
- image = sign | exp | sig;
- break;
-
- default:
- abort ();
- }
-
- buf[0] = image;
+ encode_decimal32 (fmt, buf, r);
}
-static void
-decode_i370_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
- REAL_VALUE_TYPE *r, const long *buf)
+/* Decode a single precision DFP value in BUF into a real R. */
+static void
+decode_decimal_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
+ REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
+ const long *buf ATTRIBUTE_UNUSED)
{
- unsigned long sign, sig, image = buf[0];
- int exp;
-
- sign = (image >> 31) & 1;
- exp = (image >> 24) & 0x7f;
- sig = image & 0xffffff;
-
- memset (r, 0, sizeof (*r));
-
- if (exp || sig)
- {
- r->cl = rvc_normal;
- r->sign = sign;
- SET_REAL_EXP (r, (exp - 64) * 4);
- r->sig[SIGSZ-1] = sig << (HOST_BITS_PER_LONG - 24);
- normalize (r);
- }
+ decode_decimal32 (fmt, r, buf);
}
-static void
-encode_i370_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
- long *buf, const REAL_VALUE_TYPE *r)
+/* Encode real R into a double precision DFP value in BUF. */
+static void
+encode_decimal_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
+ long *buf ATTRIBUTE_UNUSED,
+ const REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED)
{
- unsigned long sign, exp, image_hi, image_lo;
-
- sign = r->sign << 31;
-
- switch (r->cl)
- {
- case rvc_zero:
- image_hi = image_lo = 0;
- break;
-
- case rvc_inf:
- case rvc_nan:
- image_hi = 0x7fffffff | sign;
- image_lo = 0xffffffff;
- break;
-
- case rvc_normal:
- if (HOST_BITS_PER_LONG == 64)
- {
- image_hi = r->sig[SIGSZ-1];
- image_lo = (image_hi >> (64 - 56)) & 0xffffffff;
- image_hi = (image_hi >> (64 - 56 + 1) >> 31) & 0xffffff;
- }
- else
- {
- image_hi = r->sig[SIGSZ-1];
- image_lo = r->sig[SIGSZ-2];
- image_lo = (image_lo >> 8) | (image_hi << 24);
- image_hi >>= 8;
- }
-
- exp = ((REAL_EXP (r) / 4) + 64) << 24;
- image_hi |= sign | exp;
- break;
-
- default:
- abort ();
- }
-
- if (FLOAT_WORDS_BIG_ENDIAN)
- buf[0] = image_hi, buf[1] = image_lo;
- else
- buf[0] = image_lo, buf[1] = image_hi;
+ encode_decimal64 (fmt, buf, r);
}
-static void
-decode_i370_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
- REAL_VALUE_TYPE *r, const long *buf)
+/* Decode a double precision DFP value in BUF into a real R. */
+static void
+decode_decimal_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
+ REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
+ const long *buf ATTRIBUTE_UNUSED)
{
- unsigned long sign, image_hi, image_lo;
- int exp;
-
- if (FLOAT_WORDS_BIG_ENDIAN)
- image_hi = buf[0], image_lo = buf[1];
- else
- image_lo = buf[0], image_hi = buf[1];
-
- sign = (image_hi >> 31) & 1;
- exp = (image_hi >> 24) & 0x7f;
- image_hi &= 0xffffff;
- image_lo &= 0xffffffff;
-
- memset (r, 0, sizeof (*r));
-
- if (exp || image_hi || image_lo)
- {
- r->cl = rvc_normal;
- r->sign = sign;
- SET_REAL_EXP (r, (exp - 64) * 4 + (SIGNIFICAND_BITS - 56));
+ decode_decimal64 (fmt, r, buf);
+}
- if (HOST_BITS_PER_LONG == 32)
- {
- r->sig[0] = image_lo;
- r->sig[1] = image_hi;
- }
- else
- r->sig[0] = image_lo | (image_hi << 31 << 1);
+/* Encode real R into a quad precision DFP value in BUF. */
+static void
+encode_decimal_quad (const struct real_format *fmt ATTRIBUTE_UNUSED,
+ long *buf ATTRIBUTE_UNUSED,
+ const REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED)
+{
+ encode_decimal128 (fmt, buf, r);
+}
- normalize (r);
- }
+/* Decode a quad precision DFP value in BUF into a real R. */
+static void
+decode_decimal_quad (const struct real_format *fmt ATTRIBUTE_UNUSED,
+ REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
+ const long *buf ATTRIBUTE_UNUSED)
+{
+ decode_decimal128 (fmt, r, buf);
}
-const struct real_format i370_single_format =
+/* Single precision decimal floating point (IEEE 754R). */
+const struct real_format decimal_single_format =
{
- encode_i370_single,
- decode_i370_single,
- 16,
- 4,
- 6,
- 6,
- -64,
- 63,
+ encode_decimal_single,
+ decode_decimal_single,
+ 10,
+ 7,
+ 7,
+ -95,
+ 96,
31,
- false,
- false,
- false, /* ??? The encoding does allow for "unnormals". */
- false, /* ??? The encoding does allow for "unnormals". */
+ 31,
+ true,
+ true,
+ true,
+ true,
+ true,
false
};
-const struct real_format i370_double_format =
+/* Double precision decimal floating point (IEEE 754R). */
+const struct real_format decimal_double_format =
{
- encode_i370_double,
- decode_i370_double,
+ encode_decimal_double,
+ decode_decimal_double,
+ 10,
+ 16,
16,
- 4,
- 14,
- 14,
- -64,
+ -383,
+ 384,
63,
63,
- false,
- false,
- false, /* ??? The encoding does allow for "unnormals". */
- false, /* ??? The encoding does allow for "unnormals". */
+ true,
+ true,
+ true,
+ true,
+ true,
+ false
+ };
+
+/* Quad precision decimal floating point (IEEE 754R). */
+const struct real_format decimal_quad_format =
+ {
+ encode_decimal_quad,
+ decode_decimal_quad,
+ 10,
+ 34,
+ 34,
+ -6143,
+ 6144,
+ 127,
+ 127,
+ true,
+ true,
+ true,
+ true,
+ true,
false
};
\f
break;
default:
- abort ();
+ gcc_unreachable ();
}
image = ((exp & 0xff) << 24) | (sig & 0xffffff);
break;
default:
- abort ();
+ gcc_unreachable ();
}
exp = (exp & 0xff) << 24;
encode_c4x_single,
decode_c4x_single,
2,
- 1,
24,
24,
-126,
128,
+ 23,
-1,
false,
false,
false,
false,
+ false,
false
};
encode_c4x_extended,
decode_c4x_extended,
2,
- 1,
32,
32,
-126,
128,
+ 31,
-1,
false,
false,
false,
false,
+ false,
false
};
encode_internal,
decode_internal,
2,
- 1,
SIGNIFICAND_BITS - 2,
SIGNIFICAND_BITS - 2,
-MAX_EXP,
MAX_EXP,
-1,
+ -1,
true,
true,
false,
true,
- true
+ true,
+ false
};
\f
/* Calculate the square root of X in mode MODE, and store the result
}
/* Infinity and NaN return themselves. */
- if (real_isinf (x) || real_isnan (x))
+ if (!real_isfinite (x))
{
*r = *x;
return false;
do_add (&t, &t, &dconstm1, 0);
if (mode != VOIDmode)
real_convert (r, mode, &t);
+ else
+ *r = t;
}
/* Round X to the smallest integer not less then argument, i.e. round
do_add (&t, &t, &dconst1, 0);
if (mode != VOIDmode)
real_convert (r, mode, &t);
+ else
+ *r = t;
}
/* Round X to the nearest integer, but round halfway cases away from
r->sign = x->sign;
}
+/* Convert from REAL_VALUE_TYPE to MPFR. The caller is responsible
+ for initializing and clearing the MPFR parameter. */
+
+void
+mpfr_from_real (mpfr_ptr m, const REAL_VALUE_TYPE *r, mp_rnd_t rndmode)
+{
+ /* We use a string as an intermediate type. */
+ char buf[128];
+ int ret;
+
+ /* Take care of Infinity and NaN. */
+ if (r->cl == rvc_inf)
+ {
+ mpfr_set_inf (m, r->sign == 1 ? -1 : 1);
+ return;
+ }
+
+ if (r->cl == rvc_nan)
+ {
+ mpfr_set_nan (m);
+ return;
+ }
+
+ real_to_hexadecimal (buf, r, sizeof (buf), 0, 1);
+ /* mpfr_set_str() parses hexadecimal floats from strings in the same
+ format that GCC will output them. Nothing extra is needed. */
+ ret = mpfr_set_str (m, buf, 16, rndmode);
+ gcc_assert (ret == 0);
+}
+
+/* Convert from MPFR to REAL_VALUE_TYPE, for a given type TYPE and rounding
+ mode RNDMODE. TYPE is only relevant if M is a NaN. */
+
+void
+real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, tree type, mp_rnd_t rndmode)
+{
+ /* We use a string as an intermediate type. */
+ char buf[128], *rstr;
+ mp_exp_t exp;
+
+ /* Take care of Infinity and NaN. */
+ if (mpfr_inf_p (m))
+ {
+ real_inf (r);
+ if (mpfr_sgn (m) < 0)
+ *r = REAL_VALUE_NEGATE (*r);
+ return;
+ }
+
+ if (mpfr_nan_p (m))
+ {
+ real_nan (r, "", 1, TYPE_MODE (type));
+ return;
+ }
+
+ rstr = mpfr_get_str (NULL, &exp, 16, 0, m, rndmode);
+
+ /* The additional 12 chars add space for the sprintf below. This
+ leaves 6 digits for the exponent which is supposedly enough. */
+ gcc_assert (rstr != NULL && strlen (rstr) < sizeof (buf) - 12);
+
+ /* REAL_VALUE_ATOF expects the exponent for mantissa * 2**exp,
+ mpfr_get_str returns the exponent for mantissa * 16**exp, adjust
+ for that. */
+ exp *= 4;
+
+ if (rstr[0] == '-')
+ sprintf (buf, "-0x.%sp%d", &rstr[1], (int) exp);
+ else
+ sprintf (buf, "0x.%sp%d", rstr, (int) exp);
+
+ mpfr_free_str (rstr);
+
+ real_from_string (r, buf);
+}
+
+/* Check whether the real constant value given is an integer. */
+
+bool
+real_isinteger (const REAL_VALUE_TYPE *c, enum machine_mode mode)
+{
+ REAL_VALUE_TYPE cint;
+
+ real_trunc (&cint, mode, c);
+ return real_identical (c, &cint);
+}
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