#include "tree.h"
#include "toplev.h"
#include "real.h"
+#include "realmpfr.h"
#include "tm_p.h"
#include "dfp.h"
Both of these requirements are easily satisfied. The largest target
significand is 113 bits; we store at least 160. The smallest
- denormal number fits in 17 exponent bits; we store 27.
+ denormal number fits in 17 exponent bits; we store 26.
Note that the decimal string conversion routines are sensitive to
rounding errors. Since the raw arithmetic routines do not themselves
static void do_fix_trunc (REAL_VALUE_TYPE *, const REAL_VALUE_TYPE *);
static unsigned long rtd_divmod (REAL_VALUE_TYPE *, REAL_VALUE_TYPE *);
+static void decimal_from_integer (REAL_VALUE_TYPE *);
+static void decimal_integer_string (char *, const REAL_VALUE_TYPE *,
+ size_t);
static const REAL_VALUE_TYPE * ten_to_ptwo (int);
static const REAL_VALUE_TYPE * ten_to_mptwo (int);
real_arithmetic (REAL_VALUE_TYPE *r, int icode, const REAL_VALUE_TYPE *op0,
const REAL_VALUE_TYPE *op1)
{
- enum tree_code code = icode;
+ enum tree_code code = (enum tree_code) icode;
if (op0->decimal || (op1 && op1->decimal))
return decimal_real_arithmetic (r, code, op0, op1);
return false;
}
-/* Legacy. Similar, but return the result directly. */
+REAL_VALUE_TYPE
+real_value_negate (const REAL_VALUE_TYPE *op0)
+{
+ REAL_VALUE_TYPE r;
+ real_arithmetic (&r, NEGATE_EXPR, op0, NULL);
+ return r;
+}
REAL_VALUE_TYPE
-real_arithmetic2 (int icode, const REAL_VALUE_TYPE *op0,
- const REAL_VALUE_TYPE *op1)
+real_value_abs (const REAL_VALUE_TYPE *op0)
{
REAL_VALUE_TYPE r;
- real_arithmetic (&r, icode, op0, op1);
+ real_arithmetic (&r, ABS_EXPR, op0, NULL);
return r;
}
real_compare (int icode, const REAL_VALUE_TYPE *op0,
const REAL_VALUE_TYPE *op1)
{
- enum tree_code code = icode;
+ enum tree_code code = (enum tree_code) icode;
switch (code)
{
if (HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG)
i = r->sig[SIGSZ-1];
- else
+ else
{
gcc_assert (HOST_BITS_PER_WIDE_INT == 2 * HOST_BITS_PER_LONG);
i = r->sig[SIGSZ-1];
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
+ else
{
gcc_assert (HOST_BITS_PER_WIDE_INT == 2*HOST_BITS_PER_LONG);
high = t.sig[SIGSZ-1];
/* Initialize R from string S and desired MODE. */
-void
+void
real_from_string3 (REAL_VALUE_TYPE *r, const char *s, enum machine_mode mode)
{
if (DECIMAL_FLOAT_MODE_P (mode))
real_from_string (r, s);
if (mode != VOIDmode)
- real_convert (r, mode, r);
-}
+ real_convert (r, mode, r);
+}
/* Initialize R from the integer pair HIGH+LOW. */
normalize (r);
}
- if (mode != VOIDmode)
+ if (DECIMAL_FLOAT_MODE_P (mode))
+ decimal_from_integer (r);
+ else if (mode != VOIDmode)
real_convert (r, mode, r);
}
+/* Render R, an integral value, as a floating point constant with no
+ specified exponent. */
+
+static void
+decimal_integer_string (char *str, const REAL_VALUE_TYPE *r_orig,
+ size_t buf_size)
+{
+ int dec_exp, digit, digits;
+ REAL_VALUE_TYPE r, pten;
+ char *p;
+ bool sign;
+
+ r = *r_orig;
+
+ if (r.cl == rvc_zero)
+ {
+ strcpy (str, "0.");
+ return;
+ }
+
+ sign = r.sign;
+ r.sign = 0;
+
+ dec_exp = REAL_EXP (&r) * M_LOG10_2;
+ digits = dec_exp + 1;
+ gcc_assert ((digits + 2) < (int)buf_size);
+
+ pten = *real_digit (1);
+ times_pten (&pten, dec_exp);
+
+ p = str;
+ if (sign)
+ *p++ = '-';
+
+ digit = rtd_divmod (&r, &pten);
+ gcc_assert (digit >= 0 && digit <= 9);
+ *p++ = digit + '0';
+ while (--digits > 0)
+ {
+ times_pten (&r, 1);
+ digit = rtd_divmod (&r, &pten);
+ *p++ = digit + '0';
+ }
+ *p++ = '.';
+ *p++ = '\0';
+}
+
+/* Convert a real with an integral value to decimal float. */
+
+static void
+decimal_from_integer (REAL_VALUE_TYPE *r)
+{
+ char str[256];
+
+ decimal_integer_string (str, r, sizeof (str) - 1);
+ decimal_real_from_string (r, str);
+}
+
/* Returns 10**2**N. */
static const REAL_VALUE_TYPE *
mpfr_exp (m, m, GMP_RNDN);
real_from_mpfr (&value, m, NULL_TREE, GMP_RNDN);
mpfr_clear (m);
-
+
}
return &value;
}
fmt = REAL_MODE_FORMAT (mode);
gcc_assert (fmt);
memset (r, 0, sizeof (*r));
-
+
if (fmt->b == 10)
decimal_real_maxval (r, sign, mode);
else
/* Encode real R into a single precision DFP value in BUF. */
static void
encode_decimal_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
- long *buf ATTRIBUTE_UNUSED,
+ long *buf ATTRIBUTE_UNUSED,
const REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED)
{
encode_decimal32 (fmt, buf, r);
}
/* Decode a single precision DFP value in BUF into a real R. */
-static void
+static void
decode_decimal_single (const struct real_format *fmt ATTRIBUTE_UNUSED,
- REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
+ REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
const long *buf ATTRIBUTE_UNUSED)
{
decode_decimal32 (fmt, r, buf);
}
/* Encode real R into a double precision DFP value in BUF. */
-static void
+static void
encode_decimal_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
- long *buf ATTRIBUTE_UNUSED,
+ long *buf ATTRIBUTE_UNUSED,
const REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED)
{
encode_decimal64 (fmt, buf, r);
}
/* Decode a double precision DFP value in BUF into a real R. */
-static void
+static void
decode_decimal_double (const struct real_format *fmt ATTRIBUTE_UNUSED,
- REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
+ REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
const long *buf ATTRIBUTE_UNUSED)
{
decode_decimal64 (fmt, r, buf);
}
/* Encode real R into a quad precision DFP value in BUF. */
-static void
+static void
encode_decimal_quad (const struct real_format *fmt ATTRIBUTE_UNUSED,
long *buf ATTRIBUTE_UNUSED,
const REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED)
}
/* Decode a quad precision DFP value in BUF into a real R. */
-static void
+static void
decode_decimal_quad (const struct real_format *fmt ATTRIBUTE_UNUSED,
REAL_VALUE_TYPE *r ATTRIBUTE_UNUSED,
const long *buf ATTRIBUTE_UNUSED)
{
encode_decimal_single,
decode_decimal_single,
- 10,
+ 10,
7,
7,
-94,
true,
true,
true,
- true,
+ true,
true,
false
};
true,
true,
true,
- true,
- true,
+ true,
+ true,
+ true,
+ false
+ };
+\f
+/* Encode half-precision floats. This routine is used both for the IEEE
+ ARM alternative encodings. */
+static void
+encode_ieee_half (const struct real_format *fmt, long *buf,
+ const REAL_VALUE_TYPE *r)
+{
+ unsigned long image, sig, exp;
+ unsigned long sign = r->sign;
+ bool denormal = (r->sig[SIGSZ-1] & SIG_MSB) == 0;
+
+ image = sign << 15;
+ sig = (r->sig[SIGSZ-1] >> (HOST_BITS_PER_LONG - 11)) & 0x3ff;
+
+ switch (r->cl)
+ {
+ case rvc_zero:
+ break;
+
+ case rvc_inf:
+ if (fmt->has_inf)
+ image |= 31 << 10;
+ else
+ image |= 0x7fff;
+ break;
+
+ case rvc_nan:
+ if (fmt->has_nans)
+ {
+ if (r->canonical)
+ sig = (fmt->canonical_nan_lsbs_set ? (1 << 9) - 1 : 0);
+ if (r->signalling == fmt->qnan_msb_set)
+ sig &= ~(1 << 9);
+ else
+ sig |= 1 << 9;
+ if (sig == 0)
+ sig = 1 << 8;
+
+ image |= 31 << 10;
+ image |= sig;
+ }
+ else
+ image |= 0x3ff;
+ break;
+
+ case rvc_normal:
+ /* Recall that IEEE numbers are interpreted as 1.F x 2**exp,
+ whereas the intermediate representation is 0.F x 2**exp.
+ Which means we're off by one. */
+ if (denormal)
+ exp = 0;
+ else
+ exp = REAL_EXP (r) + 15 - 1;
+ image |= exp << 10;
+ image |= sig;
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
+
+ buf[0] = image;
+}
+
+/* Decode half-precision floats. This routine is used both for the IEEE
+ ARM alternative encodings. */
+static void
+decode_ieee_half (const struct real_format *fmt, REAL_VALUE_TYPE *r,
+ const long *buf)
+{
+ unsigned long image = buf[0] & 0xffff;
+ bool sign = (image >> 15) & 1;
+ int exp = (image >> 10) & 0x1f;
+
+ memset (r, 0, sizeof (*r));
+ image <<= HOST_BITS_PER_LONG - 11;
+ image &= ~SIG_MSB;
+
+ if (exp == 0)
+ {
+ if (image && fmt->has_denorm)
+ {
+ r->cl = rvc_normal;
+ r->sign = sign;
+ SET_REAL_EXP (r, -14);
+ r->sig[SIGSZ-1] = image << 1;
+ normalize (r);
+ }
+ else if (fmt->has_signed_zero)
+ r->sign = sign;
+ }
+ else if (exp == 31 && (fmt->has_nans || fmt->has_inf))
+ {
+ if (image)
+ {
+ r->cl = rvc_nan;
+ r->sign = sign;
+ r->signalling = (((image >> (HOST_BITS_PER_LONG - 2)) & 1)
+ ^ fmt->qnan_msb_set);
+ r->sig[SIGSZ-1] = image;
+ }
+ else
+ {
+ r->cl = rvc_inf;
+ r->sign = sign;
+ }
+ }
+ else
+ {
+ r->cl = rvc_normal;
+ r->sign = sign;
+ SET_REAL_EXP (r, exp - 15 + 1);
+ r->sig[SIGSZ-1] = image | SIG_MSB;
+ }
+}
+
+/* Half-precision format, as specified in IEEE 754R. */
+const struct real_format ieee_half_format =
+ {
+ encode_ieee_half,
+ decode_ieee_half,
+ 2,
+ 11,
+ 11,
+ -13,
+ 16,
+ 15,
+ 15,
+ false,
+ true,
+ true,
+ true,
+ true,
+ true,
true,
false
};
+
+/* ARM's alternative half-precision format, similar to IEEE but with
+ no reserved exponent value for NaNs and infinities; rather, it just
+ extends the range of exponents by one. */
+const struct real_format arm_half_format =
+ {
+ encode_ieee_half,
+ decode_ieee_half,
+ 2,
+ 11,
+ 11,
+ -13,
+ 17,
+ 15,
+ 15,
+ false,
+ true,
+ false,
+ false,
+ true,
+ true,
+ false,
+ false
+ };
\f
/* A synthetic "format" for internal arithmetic. It's the size of the
internal significand minus the two bits needed for proper rounding.
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
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