/* real.c - software floating point emulation.
- Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2002, 2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
+ Copyright (C) 1993-2015 Free Software Foundation, Inc.
Contributed by Stephen L. Moshier (moshier@world.std.com).
Re-written by Richard Henderson <rth@redhat.com>
#include "system.h"
#include "coretypes.h"
#include "tm.h"
+#include "alias.h"
+#include "symtab.h"
#include "tree.h"
-#include "toplev.h"
-#include "real.h"
+#include "diagnostic-core.h"
+#include "realmpfr.h"
#include "tm_p.h"
#include "dfp.h"
+#include "rtl.h"
+#include "options.h"
/* The floating point model used internally is not exactly IEEE 754
compliant, and close to the description in the ISO C99 standard,
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.
-
- Note that the decimal string conversion routines are sensitive to
- rounding errors. Since the raw arithmetic routines do not themselves
- 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. */
+ denormal number fits in 17 exponent bits; we store 26. */
/* Used to classify two numbers simultaneously. */
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);
/* Sign of zero doesn't matter for compares. */
return 0;
+ case CLASS2 (rvc_normal, rvc_zero):
+ /* Decimal float zero is special and uses rvc_normal, not rvc_zero. */
+ if (a->decimal)
+ return decimal_do_compare (a, b, nan_result);
+ /* Fall through. */
case CLASS2 (rvc_inf, rvc_zero):
case CLASS2 (rvc_inf, rvc_normal):
- case CLASS2 (rvc_normal, rvc_zero):
return (a->sign ? -1 : 1);
case CLASS2 (rvc_inf, rvc_inf):
return -a->sign - -b->sign;
case CLASS2 (rvc_zero, rvc_normal):
+ /* Decimal float zero is special and uses rvc_normal, not rvc_zero. */
+ if (b->decimal)
+ return decimal_do_compare (a, b, nan_result);
+ /* Fall through. */
case CLASS2 (rvc_zero, rvc_inf):
case CLASS2 (rvc_normal, rvc_inf):
return (b->sign ? 1 : -1);
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, icode, op0, op1);
+ return decimal_real_arithmetic (r, code, op0, op1);
switch (code)
{
case PLUS_EXPR:
+ /* Clear any padding areas in *r if it isn't equal to one of the
+ operands so that we can later do bitwise comparisons later on. */
+ if (r != op0 && r != op1)
+ memset (r, '\0', sizeof (*r));
return do_add (r, op0, op1, 0);
case MINUS_EXPR:
+ if (r != op0 && r != op1)
+ memset (r, '\0', sizeof (*r));
return do_add (r, op0, op1, 1);
case MULT_EXPR:
+ if (r != op0 && r != op1)
+ memset (r, '\0', sizeof (*r));
return do_multiply (r, op0, op1);
case RDIV_EXPR:
+ if (r != op0 && r != op1)
+ memset (r, '\0', sizeof (*r));
return do_divide (r, op0, op1);
case MIN_EXPR:
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)
{
mode MODE. Return true if successful. */
bool
-exact_real_inverse (enum machine_mode mode, REAL_VALUE_TYPE *r)
+exact_real_inverse (machine_mode mode, REAL_VALUE_TYPE *r)
{
const REAL_VALUE_TYPE *one = real_digit (1);
REAL_VALUE_TYPE u;
*r = u;
return true;
}
+
+/* Return true if arithmetic on values in IMODE that were promoted
+ from values in TMODE is equivalent to direct arithmetic on values
+ in TMODE. */
+
+bool
+real_can_shorten_arithmetic (machine_mode imode, machine_mode tmode)
+{
+ const struct real_format *tfmt, *ifmt;
+ tfmt = REAL_MODE_FORMAT (tmode);
+ ifmt = REAL_MODE_FORMAT (imode);
+ /* These conditions are conservative rather than trying to catch the
+ exact boundary conditions; the main case to allow is IEEE float
+ and double. */
+ return (ifmt->b == tfmt->b
+ && ifmt->p > 2 * tfmt->p
+ && ifmt->emin < 2 * tfmt->emin - tfmt->p - 2
+ && ifmt->emin < tfmt->emin - tfmt->emax - tfmt->p - 2
+ && ifmt->emax > 2 * tfmt->emax + 2
+ && ifmt->emax > tfmt->emax - tfmt->emin + tfmt->p + 2
+ && ifmt->round_towards_zero == tfmt->round_towards_zero
+ && (ifmt->has_sign_dependent_rounding
+ == tfmt->has_sign_dependent_rounding)
+ && ifmt->has_nans >= tfmt->has_nans
+ && ifmt->has_inf >= tfmt->has_inf
+ && ifmt->has_signed_zero >= tfmt->has_signed_zero
+ && !MODE_COMPOSITE_P (tmode)
+ && !MODE_COMPOSITE_P (imode));
+}
\f
/* Render R as an integer. */
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];
}
}
-/* Likewise, but to an integer pair, HI+LOW. */
+/* Likewise, but producing a wide-int of PRECISION. If the value cannot
+ be represented in precision, *FAIL is set to TRUE. */
-void
-real_to_integer2 (HOST_WIDE_INT *plow, HOST_WIDE_INT *phigh,
- const REAL_VALUE_TYPE *r)
+wide_int
+real_to_integer (const REAL_VALUE_TYPE *r, bool *fail, int precision)
{
- REAL_VALUE_TYPE t;
- HOST_WIDE_INT low, high;
+ HOST_WIDE_INT val[2 * WIDE_INT_MAX_ELTS];
int exp;
+ int words, w;
+ wide_int result;
switch (r->cl)
{
case rvc_zero:
underflow:
- low = high = 0;
- break;
+ return wi::zero (precision);
case rvc_inf:
case rvc_nan:
overflow:
- high = (unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT - 1);
+ *fail = true;
+
if (r->sign)
- low = 0;
+ return wi::set_bit_in_zero (precision - 1, precision);
else
- {
- high--;
- low = -1;
- }
- break;
+ return ~wi::set_bit_in_zero (precision - 1, precision);
case rvc_normal:
if (r->decimal)
- {
- decimal_real_to_integer2 (plow, phigh, r);
- return;
- }
-
+ return decimal_real_to_integer (r, fail, precision);
+
exp = REAL_EXP (r);
if (exp <= 0)
goto underflow;
undefined, so it doesn't matter what we return, and some callers
expect to be able to use this routine for both signed and
unsigned conversions. */
- if (exp > 2*HOST_BITS_PER_WIDE_INT)
+ if (exp > precision)
goto overflow;
- rshift_significand (&t, r, 2*HOST_BITS_PER_WIDE_INT - exp);
- if (HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG)
+ /* Put the significand into a wide_int that has precision W, which
+ is the smallest HWI-multiple that has at least PRECISION bits.
+ This ensures that the top bit of the significand is in the
+ top bit of the wide_int. */
+ words = (precision + HOST_BITS_PER_WIDE_INT - 1) / HOST_BITS_PER_WIDE_INT;
+ w = words * HOST_BITS_PER_WIDE_INT;
+
+#if (HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG)
+ for (int i = 0; i < words; i++)
{
- high = t.sig[SIGSZ-1];
- low = t.sig[SIGSZ-2];
+ int j = SIGSZ - words + i;
+ val[i] = (j < 0) ? 0 : r->sig[j];
}
- else
+#else
+ gcc_assert (HOST_BITS_PER_WIDE_INT == 2 * HOST_BITS_PER_LONG);
+ for (int i = 0; i < words; i++)
{
- 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 = t.sig[SIGSZ-3];
- low = low << (HOST_BITS_PER_LONG - 1) << 1;
- low |= t.sig[SIGSZ-4];
+ int j = SIGSZ - (words * 2) + (i * 2);
+ if (j < 0)
+ val[i] = 0;
+ else
+ val[i] = r->sig[j];
+ j += 1;
+ if (j >= 0)
+ val[i] |= (unsigned HOST_WIDE_INT) r->sig[j] << HOST_BITS_PER_LONG;
}
+#endif
+ /* Shift the value into place and truncate to the desired precision. */
+ result = wide_int::from_array (val, words, w);
+ result = wi::lrshift (result, w - exp);
+ result = wide_int::from (result, precision, UNSIGNED);
if (r->sign)
- {
- if (low == 0)
- high = -high;
- else
- low = -low, high = ~high;
- }
- break;
+ return -result;
+ else
+ return result;
default:
gcc_unreachable ();
}
-
- *plow = low;
- *phigh = high;
}
/* A subroutine of real_to_decimal. Compute the quotient and remainder
void
real_to_decimal_for_mode (char *str, const REAL_VALUE_TYPE *r_orig,
size_t buf_size, size_t digits,
- int crop_trailing_zeros, enum machine_mode mode)
+ int crop_trailing_zeros, machine_mode mode)
{
const struct real_format *fmt = NULL;
const REAL_VALUE_TYPE *one, *ten;
else
{
/* Decimal floating point. */
- const REAL_VALUE_TYPE *ten = ten_to_ptwo (0);
- int d;
+ const char *cstr = str;
+ mpfr_t m;
+ bool inexact;
- while (*str == '0')
- str++;
- while (ISDIGIT (*str))
+ while (*cstr == '0')
+ cstr++;
+ if (*cstr == '.')
{
- d = *str++ - '0';
- do_multiply (r, r, ten);
- if (d)
- do_add (r, r, real_digit (d), 0);
- }
- if (*str == '.')
- {
- str++;
- if (r->cl == rvc_zero)
- {
- while (*str == '0')
- str++, exp--;
- }
- while (ISDIGIT (*str))
- {
- d = *str++ - '0';
- do_multiply (r, r, ten);
- if (d)
- do_add (r, r, real_digit (d), 0);
- exp--;
- }
+ cstr++;
+ while (*cstr == '0')
+ cstr++;
}
/* If the mantissa is zero, ignore the exponent. */
- if (r->cl == rvc_zero)
+ if (!ISDIGIT (*cstr))
goto is_a_zero;
- if (*str == 'e' || *str == 'E')
+ /* Nonzero value, possibly overflowing or underflowing. */
+ mpfr_init2 (m, SIGNIFICAND_BITS);
+ inexact = mpfr_strtofr (m, str, NULL, 10, GMP_RNDZ);
+ /* The result should never be a NaN, and because the rounding is
+ toward zero should never be an infinity. */
+ gcc_assert (!mpfr_nan_p (m) && !mpfr_inf_p (m));
+ if (mpfr_zero_p (m) || mpfr_get_exp (m) < -MAX_EXP + 4)
{
- bool exp_neg = false;
-
- str++;
- if (*str == '-')
- {
- exp_neg = true;
- str++;
- }
- else if (*str == '+')
- str++;
-
- d = 0;
- while (ISDIGIT (*str))
- {
- d *= 10;
- d += *str - '0';
- if (d > MAX_EXP)
- {
- /* Overflowed the exponent. */
- if (exp_neg)
- goto underflow;
- else
- goto overflow;
- }
- str++;
- }
- if (exp_neg)
- d = -d;
- exp += d;
+ mpfr_clear (m);
+ goto underflow;
+ }
+ else if (mpfr_get_exp (m) > MAX_EXP - 4)
+ {
+ mpfr_clear (m);
+ goto overflow;
+ }
+ else
+ {
+ real_from_mpfr (r, m, NULL_TREE, GMP_RNDZ);
+ /* 1 to 3 bits may have been shifted off (with a sticky bit)
+ because the hex digits used in real_from_mpfr did not
+ start with a digit 8 to f, but the exponent bounds above
+ should have avoided underflow or overflow. */
+ gcc_assert (r->cl == rvc_normal);
+ /* Set a sticky bit if mpfr_strtofr was inexact. */
+ r->sig[0] |= inexact;
+ mpfr_clear (m);
}
-
- if (exp)
- times_pten (r, exp);
}
r->sign = sign;
/* Legacy. Similar, but return the result directly. */
REAL_VALUE_TYPE
-real_from_string2 (const char *s, enum machine_mode mode)
+real_from_string2 (const char *s, machine_mode mode)
{
REAL_VALUE_TYPE r;
/* Initialize R from string S and desired MODE. */
-void
-real_from_string3 (REAL_VALUE_TYPE *r, const char *s, enum machine_mode mode)
+void
+real_from_string3 (REAL_VALUE_TYPE *r, const char *s, machine_mode mode)
{
if (DECIMAL_FLOAT_MODE_P (mode))
decimal_real_from_string (r, s);
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. */
+/* Initialize R from the wide_int VAL_IN. The MODE is not VOIDmode,*/
void
-real_from_integer (REAL_VALUE_TYPE *r, enum machine_mode mode,
- unsigned HOST_WIDE_INT low, HOST_WIDE_INT high,
- int unsigned_p)
+real_from_integer (REAL_VALUE_TYPE *r, machine_mode mode,
+ const wide_int_ref &val_in, signop sgn)
{
- if (low == 0 && high == 0)
+ if (val_in == 0)
get_zero (r, 0);
else
{
+ unsigned int len = val_in.get_precision ();
+ int i, j, e = 0;
+ int maxbitlen = MAX_BITSIZE_MODE_ANY_INT + HOST_BITS_PER_WIDE_INT;
+ const unsigned int realmax = (SIGNIFICAND_BITS / HOST_BITS_PER_WIDE_INT
+ * HOST_BITS_PER_WIDE_INT);
+
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->sign = wi::neg_p (val_in, sgn);
+
+ /* We have to ensure we can negate the largest negative number. */
+ wide_int val = wide_int::from (val_in, maxbitlen, sgn);
if (r->sign)
+ val = -val;
+
+ /* Ensure a multiple of HOST_BITS_PER_WIDE_INT, ceiling, as elt
+ won't work with precisions that are not a multiple of
+ HOST_BITS_PER_WIDE_INT. */
+ len += HOST_BITS_PER_WIDE_INT - 1;
+
+ /* Ensure we can represent the largest negative number. */
+ len += 1;
+
+ len = len/HOST_BITS_PER_WIDE_INT * HOST_BITS_PER_WIDE_INT;
+
+ /* Cap the size to the size allowed by real.h. */
+ if (len > realmax)
{
- high = ~high;
- if (low == 0)
- high += 1;
- else
- low = -low;
+ HOST_WIDE_INT cnt_l_z;
+ cnt_l_z = wi::clz (val);
+
+ if (maxbitlen - cnt_l_z > realmax)
+ {
+ e = maxbitlen - cnt_l_z - realmax;
+
+ /* This value is too large, we must shift it right to
+ preserve all the bits we can, and then bump the
+ exponent up by that amount. */
+ val = wi::lrshift (val, e);
+ }
+ len = realmax;
}
+ /* Clear out top bits so elt will work with precisions that aren't
+ a multiple of HOST_BITS_PER_WIDE_INT. */
+ val = wide_int::from (val, len, sgn);
+ len = len / HOST_BITS_PER_WIDE_INT;
+
+ SET_REAL_EXP (r, len * HOST_BITS_PER_WIDE_INT + e);
+
+ j = SIGSZ - 1;
if (HOST_BITS_PER_LONG == HOST_BITS_PER_WIDE_INT)
- {
- r->sig[SIGSZ-1] = high;
- r->sig[SIGSZ-2] = low;
- }
+ for (i = len - 1; i >= 0; i--)
+ {
+ r->sig[j--] = val.elt (i);
+ if (j < 0)
+ break;
+ }
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;
+ for (i = len - 1; i >= 0; i--)
+ {
+ HOST_WIDE_INT e = val.elt (i);
+ r->sig[j--] = e >> (HOST_BITS_PER_LONG - 1) >> 1;
+ if (j < 0)
+ break;
+ r->sig[j--] = e;
+ if (j < 0)
+ break;
+ }
}
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 *
for (i = 0; i < n; ++i)
t *= t;
- real_from_integer (&tens[n], VOIDmode, t, 0, 1);
+ real_from_integer (&tens[n], VOIDmode, t, UNSIGNED);
}
else
{
gcc_assert (n <= 9);
if (n > 0 && num[n].cl == rvc_zero)
- real_from_integer (&num[n], VOIDmode, n, 0, 1);
+ real_from_integer (&num[n], VOIDmode, n, UNSIGNED);
return &num[n];
}
do_divide (r, r, &pten);
}
-/* Returns the special REAL_VALUE_TYPE enumerated by E. */
+/* Returns the special REAL_VALUE_TYPE corresponding to 'e'. */
const REAL_VALUE_TYPE *
-get_real_const (enum real_value_const e)
+dconst_e_ptr (void)
{
- static REAL_VALUE_TYPE value[rv_max];
+ static REAL_VALUE_TYPE value;
+
+ /* Initialize mathematical constants for constant folding builtins.
+ These constants need to be given to at least 160 bits precision. */
+ if (value.cl == rvc_zero)
+ {
+ mpfr_t m;
+ mpfr_init2 (m, SIGNIFICAND_BITS);
+ mpfr_set_ui (m, 1, GMP_RNDN);
+ mpfr_exp (m, m, GMP_RNDN);
+ real_from_mpfr (&value, m, NULL_TREE, GMP_RNDN);
+ mpfr_clear (m);
+
+ }
+ return &value;
+}
+
+/* Returns the special REAL_VALUE_TYPE corresponding to 1/3. */
- gcc_assert (e < rv_max);
+const REAL_VALUE_TYPE *
+dconst_third_ptr (void)
+{
+ static REAL_VALUE_TYPE value;
/* Initialize mathematical constants for constant folding builtins.
These constants need to be given to at least 160 bits precision. */
- if (value[e].cl == rvc_zero)
- switch (e)
+ if (value.cl == rvc_zero)
{
- case rv_e:
- {
- mpfr_t m;
- mpfr_init2 (m, SIGNIFICAND_BITS);
- mpfr_set_ui (m, 1, GMP_RNDN);
- mpfr_exp (m, m, GMP_RNDN);
- real_from_mpfr (&value[e], m, NULL_TREE, GMP_RNDN);
- mpfr_clear (m);
- }
- break;
- case rv_third:
- real_arithmetic (&value[e], RDIV_EXPR, &dconst1, real_digit (3));
- break;
- case rv_sqrt2:
- {
- mpfr_t m;
- mpfr_init2 (m, SIGNIFICAND_BITS);
- mpfr_sqrt_ui (m, 2, GMP_RNDN);
- real_from_mpfr (&value[e], m, NULL_TREE, GMP_RNDN);
- mpfr_clear (m);
- }
- break;
- default:
- gcc_unreachable();
+ real_arithmetic (&value, RDIV_EXPR, &dconst1, real_digit (3));
}
+ return &value;
+}
+
+/* Returns the special REAL_VALUE_TYPE corresponding to sqrt(2). */
+
+const REAL_VALUE_TYPE *
+dconst_sqrt2_ptr (void)
+{
+ static REAL_VALUE_TYPE value;
- return &value[e];
+ /* Initialize mathematical constants for constant folding builtins.
+ These constants need to be given to at least 160 bits precision. */
+ if (value.cl == rvc_zero)
+ {
+ mpfr_t m;
+ mpfr_init2 (m, SIGNIFICAND_BITS);
+ mpfr_sqrt_ui (m, 2, GMP_RNDN);
+ real_from_mpfr (&value, m, NULL_TREE, GMP_RNDN);
+ mpfr_clear (m);
+ }
+ return &value;
}
/* Fills R with +Inf. */
bool
real_nan (REAL_VALUE_TYPE *r, const char *str, int quiet,
- enum machine_mode mode)
+ machine_mode mode)
{
const struct real_format *fmt;
If SIGN is nonzero, R is set to the most negative finite value. */
void
-real_maxval (REAL_VALUE_TYPE *r, int sign, enum machine_mode mode)
+real_maxval (REAL_VALUE_TYPE *r, int sign, machine_mode mode)
{
const struct real_format *fmt;
int np2;
fmt = REAL_MODE_FORMAT (mode);
gcc_assert (fmt);
memset (r, 0, sizeof (*r));
-
+
if (fmt->b == 10)
decimal_real_maxval (r, sign, mode);
else
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);
+ clear_significand_bit (r, SIGNIFICAND_BITS - fmt->pnan - 1);
}
}
/* Fills R with 2**N. */
void
-real_2expN (REAL_VALUE_TYPE *r, int n, enum machine_mode fmode)
+real_2expN (REAL_VALUE_TYPE *r, int n, machine_mode fmode)
{
memset (r, 0, sizeof (*r));
/* Extend or truncate to a new mode. */
void
-real_convert (REAL_VALUE_TYPE *r, enum machine_mode mode,
+real_convert (REAL_VALUE_TYPE *r, machine_mode mode,
const REAL_VALUE_TYPE *a)
{
const struct real_format *fmt;
/* Legacy. Likewise, except return the struct directly. */
REAL_VALUE_TYPE
-real_value_truncate (enum machine_mode mode, REAL_VALUE_TYPE a)
+real_value_truncate (machine_mode mode, REAL_VALUE_TYPE a)
{
REAL_VALUE_TYPE r;
real_convert (&r, mode, &a);
/* Return true if truncating to MODE is exact. */
bool
-exact_real_truncate (enum machine_mode mode, const REAL_VALUE_TYPE *a)
+exact_real_truncate (machine_mode mode, const REAL_VALUE_TYPE *a)
{
const struct real_format *fmt;
REAL_VALUE_TYPE t;
/* Similar, but look up the format from MODE. */
long
-real_to_target (long *buf, const REAL_VALUE_TYPE *r, enum machine_mode mode)
+real_to_target (long *buf, const REAL_VALUE_TYPE *r, machine_mode mode)
{
const struct real_format *fmt;
/* Similar, but look up the format from MODE. */
void
-real_from_target (REAL_VALUE_TYPE *r, const long *buf, enum machine_mode mode)
+real_from_target (REAL_VALUE_TYPE *r, const long *buf, machine_mode mode)
{
const struct real_format *fmt;
/* ??? Legacy. Should get access to real_format directly. */
int
-significand_size (enum machine_mode mode)
+significand_size (machine_mode mode)
{
const struct real_format *fmt;
gcc_unreachable ();
}
- if (sizeof(unsigned long) > sizeof(unsigned int))
+ if (sizeof (unsigned long) > sizeof (unsigned int))
for (i = 0; i < SIGSZ; ++i)
{
unsigned long s = r->sig[i];
true,
true,
true,
- false
+ true,
+ false,
+ "ieee_single"
};
const struct real_format mips_single_format =
true,
true,
true,
+ true,
false,
- true
+ true,
+ "mips_single"
};
const struct real_format motorola_single_format =
true,
true,
true,
- true
+ true,
+ true,
+ "motorola_single"
};
/* SPU Single Precision (Extended-Range Mode) format is the same as IEEE
true,
false,
false,
+ false,
true,
true,
false,
- false
+ false,
+ "spu_single"
};
\f
/* IEEE double-precision format. */
true,
true,
true,
- false
+ true,
+ false,
+ "ieee_double"
};
const struct real_format mips_double_format =
true,
true,
true,
+ true,
false,
- true
+ true,
+ "mips_double"
};
const struct real_format motorola_double_format =
true,
true,
true,
- true
+ true,
+ true,
+ "motorola_double"
};
\f
/* IEEE extended real format. This comes in three flavors: Intel's as
long intermed[3];
encode_ieee_extended (fmt, intermed, r);
+ if (r->cl == rvc_inf)
+ /* For infinity clear the explicit integer bit again, so that the
+ format matches the canonical infinity generated by the FPU. */
+ intermed[1] = 0;
+
/* Motorola chips are assumed always to be big-endian. Also, the
padding in a Motorola extended real goes between the exponent and
the mantissa. At this point the mantissa is entirely within
true,
true,
true,
- true
+ true,
+ true,
+ "ieee_extended_motorola"
};
const struct real_format ieee_extended_intel_96_format =
true,
true,
true,
- false
+ true,
+ false,
+ "ieee_extended_intel_96"
};
const struct real_format ieee_extended_intel_128_format =
true,
true,
true,
- false
+ true,
+ false,
+ "ieee_extended_intel_128"
};
/* The following caters to i386 systems that set the rounding precision
true,
true,
true,
- false
+ true,
+ false,
+ "ieee_extended_intel_96_round_53"
};
\f
/* IBM 128-bit extended precision format: a pair of IEEE double precision
true,
true,
true,
- false
+ true,
+ false,
+ "ibm_extended"
};
const struct real_format mips_extended_format =
true,
true,
true,
+ true,
false,
- true
+ true,
+ "mips_extended"
};
\f
true,
true,
true,
- false
+ true,
+ false,
+ "ieee_quad"
};
const struct real_format mips_quad_format =
true,
true,
true,
+ true,
false,
- true
+ true,
+ "mips_quad"
};
\f
/* Descriptions of VAX floating point formats can be found beginning at
false,
false,
false,
- false
+ false,
+ false,
+ "vax_f"
};
const struct real_format vax_d_format =
false,
false,
false,
- false
+ false,
+ false,
+ "vax_d"
};
const struct real_format vax_g_format =
false,
false,
false,
- false
+ false,
+ false,
+ "vax_g"
};
\f
/* 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,
- -95,
- 96,
+ -94,
+ 97,
31,
31,
false,
true,
true,
true,
- true,
true,
- false
+ true,
+ true,
+ false,
+ "decimal_single"
};
/* Double precision decimal floating point (IEEE 754). */
10,
16,
16,
- -383,
- 384,
+ -382,
+ 385,
63,
63,
false,
true,
true,
true,
- false
+ true,
+ false,
+ "decimal_double"
};
/* Quad precision decimal floating point (IEEE 754). */
10,
34,
34,
- -6143,
- 6144,
+ -6142,
+ 6145,
127,
127,
false,
true,
true,
- true,
- true,
true,
- false
+ true,
+ true,
+ true,
+ false,
+ "decimal_quad"
+ };
+\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,
+ "ieee_half"
+ };
+
+/* 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,
+ "arm_half"
};
\f
/* A synthetic "format" for internal arithmetic. It's the size of the
-1,
-1,
false,
+ false,
true,
true,
false,
true,
true,
- false
+ false,
+ "real_internal"
};
\f
-/* Calculate the square root of X in mode MODE, and store the result
- in R. Return TRUE if the operation does not raise an exception.
- For details see "High Precision Division and Square Root",
- Alan H. Karp and Peter Markstein, HP Lab Report 93-93-42, June
- 1993. http://www.hpl.hp.com/techreports/93/HPL-93-42.pdf. */
-
-bool
-real_sqrt (REAL_VALUE_TYPE *r, enum machine_mode mode,
- const REAL_VALUE_TYPE *x)
-{
- static REAL_VALUE_TYPE halfthree;
- static bool init = false;
- REAL_VALUE_TYPE h, t, i;
- int iter, exp;
-
- /* sqrt(-0.0) is -0.0. */
- if (real_isnegzero (x))
- {
- *r = *x;
- return false;
- }
-
- /* Negative arguments return NaN. */
- if (real_isneg (x))
- {
- get_canonical_qnan (r, 0);
- return false;
- }
-
- /* Infinity and NaN return themselves. */
- if (!real_isfinite (x))
- {
- *r = *x;
- return false;
- }
-
- if (!init)
- {
- do_add (&halfthree, &dconst1, &dconsthalf, 0);
- init = true;
- }
-
- /* Initial guess for reciprocal sqrt, i. */
- exp = real_exponent (x);
- real_ldexp (&i, &dconst1, -exp/2);
-
- /* Newton's iteration for reciprocal sqrt, i. */
- for (iter = 0; iter < 16; iter++)
- {
- /* i(n+1) = i(n) * (1.5 - 0.5*i(n)*i(n)*x). */
- do_multiply (&t, x, &i);
- do_multiply (&h, &t, &i);
- do_multiply (&t, &h, &dconsthalf);
- do_add (&h, &halfthree, &t, 1);
- do_multiply (&t, &i, &h);
-
- /* Check for early convergence. */
- if (iter >= 6 && real_identical (&i, &t))
- break;
-
- /* ??? Unroll loop to avoid copying. */
- i = t;
- }
-
- /* Final iteration: r = i*x + 0.5*i*x*(1.0 - i*(i*x)). */
- do_multiply (&t, x, &i);
- do_multiply (&h, &t, &i);
- do_add (&i, &dconst1, &h, 1);
- do_multiply (&h, &t, &i);
- do_multiply (&i, &dconsthalf, &h);
- do_add (&h, &t, &i, 0);
-
- /* ??? We need a Tuckerman test to get the last bit. */
-
- real_convert (r, mode, &h);
- return true;
-}
-
/* Calculate X raised to the integer exponent N in mode MODE and store
the result in R. Return true if the result may be inexact due to
loss of precision. The algorithm is the classic "left-to-right binary
Algorithms", "The Art of Computer Programming", Volume 2. */
bool
-real_powi (REAL_VALUE_TYPE *r, enum machine_mode mode,
+real_powi (REAL_VALUE_TYPE *r, machine_mode mode,
const REAL_VALUE_TYPE *x, HOST_WIDE_INT n)
{
unsigned HOST_WIDE_INT bit;
towards zero, placing the result in R in mode MODE. */
void
-real_trunc (REAL_VALUE_TYPE *r, enum machine_mode mode,
+real_trunc (REAL_VALUE_TYPE *r, machine_mode mode,
const REAL_VALUE_TYPE *x)
{
do_fix_trunc (r, x);
down, placing the result in R in mode MODE. */
void
-real_floor (REAL_VALUE_TYPE *r, enum machine_mode mode,
+real_floor (REAL_VALUE_TYPE *r, machine_mode mode,
const REAL_VALUE_TYPE *x)
{
REAL_VALUE_TYPE t;
up, placing the result in R in mode MODE. */
void
-real_ceil (REAL_VALUE_TYPE *r, enum machine_mode mode,
+real_ceil (REAL_VALUE_TYPE *r, machine_mode mode,
const REAL_VALUE_TYPE *x)
{
REAL_VALUE_TYPE t;
zero. */
void
-real_round (REAL_VALUE_TYPE *r, enum machine_mode mode,
+real_round (REAL_VALUE_TYPE *r, machine_mode mode,
const REAL_VALUE_TYPE *x)
{
do_add (r, x, &dconsthalf, x->sign);
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_isinteger (const REAL_VALUE_TYPE *c, machine_mode mode)
{
REAL_VALUE_TYPE cint;
gcc_assert (strlen (buf) < len);
}
+
+/* True if mode M has a NaN representation and
+ the treatment of NaN operands is important. */
+
+bool
+HONOR_NANS (machine_mode m)
+{
+ return MODE_HAS_NANS (m) && !flag_finite_math_only;
+}
+
+bool
+HONOR_NANS (const_tree t)
+{
+ return HONOR_NANS (element_mode (t));
+}
+
+bool
+HONOR_NANS (const_rtx x)
+{
+ return HONOR_NANS (GET_MODE (x));
+}
+
+/* Like HONOR_NANs, but true if we honor signaling NaNs (or sNaNs). */
+
+bool
+HONOR_SNANS (machine_mode m)
+{
+ return flag_signaling_nans && HONOR_NANS (m);
+}
+
+bool
+HONOR_SNANS (const_tree t)
+{
+ return HONOR_SNANS (element_mode (t));
+}
+
+bool
+HONOR_SNANS (const_rtx x)
+{
+ return HONOR_SNANS (GET_MODE (x));
+}
+
+/* As for HONOR_NANS, but true if the mode can represent infinity and
+ the treatment of infinite values is important. */
+
+bool
+HONOR_INFINITIES (machine_mode m)
+{
+ return MODE_HAS_INFINITIES (m) && !flag_finite_math_only;
+}
+
+bool
+HONOR_INFINITIES (const_tree t)
+{
+ return HONOR_INFINITIES (element_mode (t));
+}
+
+bool
+HONOR_INFINITIES (const_rtx x)
+{
+ return HONOR_INFINITIES (GET_MODE (x));
+}
+
+/* Like HONOR_NANS, but true if the given mode distinguishes between
+ positive and negative zero, and the sign of zero is important. */
+
+bool
+HONOR_SIGNED_ZEROS (machine_mode m)
+{
+ return MODE_HAS_SIGNED_ZEROS (m) && flag_signed_zeros;
+}
+
+bool
+HONOR_SIGNED_ZEROS (const_tree t)
+{
+ return HONOR_SIGNED_ZEROS (element_mode (t));
+}
+
+bool
+HONOR_SIGNED_ZEROS (const_rtx x)
+{
+ return HONOR_SIGNED_ZEROS (GET_MODE (x));
+}
+
+/* Like HONOR_NANS, but true if given mode supports sign-dependent rounding,
+ and the rounding mode is important. */
+
+bool
+HONOR_SIGN_DEPENDENT_ROUNDING (machine_mode m)
+{
+ return MODE_HAS_SIGN_DEPENDENT_ROUNDING (m) && flag_rounding_math;
+}
+
+bool
+HONOR_SIGN_DEPENDENT_ROUNDING (const_tree t)
+{
+ return HONOR_SIGN_DEPENDENT_ROUNDING (element_mode (t));
+}
+
+bool
+HONOR_SIGN_DEPENDENT_ROUNDING (const_rtx x)
+{
+ return HONOR_SIGN_DEPENDENT_ROUNDING (GET_MODE (x));
+}
projects / gcc.git / blobdiff