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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/subnormal.c183
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diff --git a/Build/source/libs/mpfr/mpfr-src/src/subnormal.c b/Build/source/libs/mpfr/mpfr-src/src/subnormal.c
deleted file mode 100644
index 76fccf0576f..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/subnormal.c
+++ /dev/null
@@ -1,183 +0,0 @@
-/* mpfr_subnormalize -- Subnormalize a floating point number
- emulating sub-normal numbers.
-
-Copyright 2005-2020 Free Software Foundation, Inc.
-Contributed by the AriC and Caramba projects, INRIA.
-
-This file is part of the GNU MPFR Library.
-
-The GNU MPFR Library is free software; you can redistribute it and/or modify
-it under the terms of the GNU Lesser General Public License as published by
-the Free Software Foundation; either version 3 of the License, or (at your
-option) any later version.
-
-The GNU MPFR Library is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
-License for more details.
-
-You should have received a copy of the GNU Lesser General Public License
-along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
-https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
-51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
-
-#include "mpfr-impl.h"
-
-/* For MPFR_RNDN, we can have a problem of double rounding.
- In such a case, this table helps to conclude what to do (y positive):
- Rounding Bit | Sticky Bit | inexact | Action | new inexact
- 0 | ? | ? | Trunc | sticky
- 1 | 0 | 1 | Trunc |
- 1 | 0 | 0 | Trunc if even |
- 1 | 0 | -1 | AddOneUlp |
- 1 | 1 | ? | AddOneUlp |
-
- For other rounding mode, there isn't such a problem.
- Just round it again and merge the ternary values.
-
- Set the inexact flag if the returned ternary value is non-zero.
- Set the underflow flag if a second rounding occurred (whether this
- rounding is exact or not). See
- https://sympa.inria.fr/sympa/arc/mpfr/2009-06/msg00000.html
- https://sympa.inria.fr/sympa/arc/mpfr/2009-06/msg00008.html
- https://sympa.inria.fr/sympa/arc/mpfr/2009-06/msg00010.html
-*/
-
-int
-mpfr_subnormalize (mpfr_ptr y, int old_inexact, mpfr_rnd_t rnd)
-{
- int sign;
-
- /* The subnormal exponent range is [ emin, emin + MPFR_PREC(y) - 2 ] */
- if (MPFR_LIKELY (MPFR_IS_SINGULAR (y)
- || (MPFR_GET_EXP (y) >=
- __gmpfr_emin + (mpfr_exp_t) MPFR_PREC (y) - 1)))
- MPFR_RET (old_inexact);
-
- MPFR_SET_UNDERFLOW ();
- sign = MPFR_SIGN (y);
-
- /* We have to emulate one bit rounding if EXP(y) = emin */
- if (MPFR_GET_EXP (y) == __gmpfr_emin)
- {
- /* If this is a power of 2, we don't need rounding.
- It handles cases when |y| = 0.1 * 2^emin */
- if (mpfr_powerof2_raw (y))
- MPFR_RET (old_inexact);
-
- /* We keep the same sign for y.
- Assuming Y is the real value and y the approximation
- and since y is not a power of 2: 0.5*2^emin < Y < 1*2^emin
- We also know the direction of the error thanks to ternary value. */
-
- if (rnd == MPFR_RNDN || rnd == MPFR_RNDNA)
- {
- mp_limb_t *mant, rb ,sb;
- mp_size_t s;
- /* We need the rounding bit and the sticky bit. Read them
- and use the previous table to conclude. */
- s = MPFR_LIMB_SIZE (y) - 1;
- mant = MPFR_MANT (y) + s;
- rb = *mant & (MPFR_LIMB_HIGHBIT >> 1);
- if (rb == 0)
- goto set_min;
- sb = *mant & ((MPFR_LIMB_HIGHBIT >> 1) - 1);
- while (sb == 0 && s-- != 0)
- sb = *--mant;
- if (sb != 0)
- goto set_min_p1;
- /* Rounding bit is 1 and sticky bit is 0.
- We need to examine old inexact flag to conclude. */
- if ((old_inexact > 0 && sign > 0) ||
- (old_inexact < 0 && sign < 0))
- goto set_min;
- /* If inexact != 0, return 0.1*2^(emin+1).
- Otherwise, rounding bit = 1, sticky bit = 0 and inexact = 0
- So we have 0.1100000000000000000000000*2^emin exactly.
- We return 0.1*2^(emin+1) according to the even-rounding
- rule on subnormals. Note the same holds for RNDNA. */
- goto set_min_p1;
- }
- else if (MPFR_IS_LIKE_RNDZ (rnd, MPFR_IS_NEG (y)))
- {
- set_min:
- mpfr_setmin (y, __gmpfr_emin);
- MPFR_RET (-sign);
- }
- else
- {
- set_min_p1:
- /* Note: mpfr_setmin will abort if __gmpfr_emax == __gmpfr_emin. */
- mpfr_setmin (y, __gmpfr_emin + 1);
- MPFR_RET (sign);
- }
- }
- else /* Hard case: It is more or less the same problem as mpfr_cache */
- {
- mpfr_t dest;
- mpfr_prec_t q;
- mpfr_rnd_t rnd2;
- int inexact, inex2;
-
- MPFR_ASSERTD (MPFR_GET_EXP (y) > __gmpfr_emin);
-
- /* Compute the intermediary precision */
- q = (mpfr_uexp_t) MPFR_GET_EXP (y) - __gmpfr_emin + 1;
- MPFR_ASSERTD (q >= MPFR_PREC_MIN && q < MPFR_PREC (y));
-
- /* TODO: perform the rounding in place. */
- mpfr_init2 (dest, q);
- /* Round y in dest */
- MPFR_SET_EXP (dest, MPFR_GET_EXP (y));
- MPFR_SET_SIGN (dest, sign);
- rnd2 = rnd == MPFR_RNDNA ? MPFR_RNDN : rnd;
- MPFR_RNDRAW_EVEN (inexact, dest,
- MPFR_MANT (y), MPFR_PREC (y), rnd2, sign,
- MPFR_SET_EXP (dest, MPFR_GET_EXP (dest) + 1));
- if (MPFR_LIKELY (old_inexact != 0))
- {
- if (MPFR_UNLIKELY (rnd2 == MPFR_RNDN &&
- (inexact == MPFR_EVEN_INEX ||
- inexact == -MPFR_EVEN_INEX)))
- {
- /* If both roundings are in the same direction,
- we have to go back in the other direction.
- For MPFR_RNDNA it is the same, since we are not
- exactly in the middle case (old_inexact != 0). */
- if (SAME_SIGN (inexact, old_inexact))
- {
- if (SAME_SIGN (inexact, MPFR_INT_SIGN (y)))
- mpfr_nexttozero (dest);
- else /* subnormal range, thus no overflow */
- {
- mpfr_nexttoinf (dest);
- MPFR_ASSERTD(!MPFR_IS_INF (dest));
- }
- inexact = -inexact;
- }
- }
- else if (MPFR_UNLIKELY (inexact == 0))
- inexact = old_inexact;
- }
- else if (rnd == MPFR_RNDNA &&
- (inexact == MPFR_EVEN_INEX || inexact == -MPFR_EVEN_INEX))
- {
- /* We are in the middle case: since we used RNDN to round, we should
- round in the opposite direction when inexact has the opposite
- sign of y. */
- if (!SAME_SIGN (inexact, MPFR_INT_SIGN (y)))
- {
- mpfr_nexttoinf (dest);
- MPFR_ASSERTD(!MPFR_IS_INF (dest));
- inexact = -inexact;
- }
- }
-
- inex2 = mpfr_set (y, dest, rnd);
- MPFR_ASSERTN (inex2 == 0);
- MPFR_ASSERTN (MPFR_IS_PURE_FP (y));
- mpfr_clear (dest);
-
- MPFR_RET (inexact);
- }
-}