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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/set.c127
1 files changed, 123 insertions, 4 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/set.c b/Build/source/libs/mpfr/mpfr-src/src/set.c
index 4d4d5ecfaed..39b93e14bcc 100644
--- a/Build/source/libs/mpfr/mpfr-src/src/set.c
+++ b/Build/source/libs/mpfr/mpfr-src/src/set.c
@@ -23,7 +23,7 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
#include "mpfr-impl.h"
/* set a to abs(b) * signb: a=b when signb = SIGN(b), a=abs(b) when signb=1 */
-int
+MPFR_HOT_FUNCTION_ATTR int
mpfr_set4 (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode, int signb)
{
/* Sign is ALWAYS copied */
@@ -43,7 +43,7 @@ mpfr_set4 (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode, int signb)
else
MPFR_RET (0);
}
- else if (MPFR_LIKELY (MPFR_PREC (b) == MPFR_PREC (a)))
+ else if (MPFR_PREC (b) == MPFR_PREC (a))
{
/* Same precision and b is not singular:
* just copy the mantissa, and set the exponent and the sign
@@ -57,8 +57,9 @@ mpfr_set4 (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode, int signb)
/* Else Round B inside a */
MPFR_RNDRAW (inex, a, MPFR_MANT (b), MPFR_PREC (b), rnd_mode, signb,
- if (MPFR_UNLIKELY ( ++MPFR_EXP (a) > __gmpfr_emax))
- return mpfr_overflow (a, rnd_mode, signb) );
+ if (MPFR_UNLIKELY (++ MPFR_EXP (a) > __gmpfr_emax))
+ return mpfr_overflow (a, rnd_mode, signb)
+ );
MPFR_RET (inex);
}
}
@@ -78,3 +79,121 @@ mpfr_abs (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode)
{
return mpfr_set4 (a, b, rnd_mode, MPFR_SIGN_POS);
}
+
+/* Round (u, inex) into s with rounding mode rnd, where inex is the ternary
+ value associated to u with the *same* rounding mode.
+ Assumes PREC(u) = 2*PREC(s).
+ The main algorithm is the following:
+ rnd=RNDZ: inex2 = mpfr_set (s, u, rnd_mode); return inex2 | inex;
+ (a negative value, if any, is preserved in inex2 | inex)
+ rnd=RNDA: idem
+ rnd=RNDN: inex2 = mpfr_set (s, u, rnd_mode);
+ if (inex2) return inex2; else return inex; */
+int
+mpfr_set_1_2 (mpfr_ptr s, mpfr_srcptr u, mpfr_rnd_t rnd_mode, int inex)
+{
+ mpfr_prec_t p = MPFR_PREC(s);
+ mpfr_prec_t sh = GMP_NUMB_BITS - p;
+ mp_limb_t rb, sb;
+ mp_limb_t *sp = MPFR_MANT(s);
+ mp_limb_t *up = MPFR_MANT(u);
+ mp_limb_t mask;
+ int inex2;
+
+ if (MPFR_UNLIKELY(MPFR_IS_SINGULAR(u)))
+ {
+ mpfr_set (s, u, rnd_mode);
+ return inex;
+ }
+
+ MPFR_ASSERTD(MPFR_PREC(u) == 2 * MPFR_PREC(s));
+
+ if (MPFR_PREC(s) < GMP_NUMB_BITS)
+ {
+ mask = MPFR_LIMB_MASK(sh);
+
+ if (MPFR_PREC(u) <= GMP_NUMB_BITS)
+ {
+ mp_limb_t u0 = up[0];
+
+ /* it suffices to round (u0, inex) */
+ rb = u0 & (MPFR_LIMB_ONE << (sh - 1));
+ sb = (u0 & mask) ^ rb;
+ sp[0] = u0 & ~mask;
+ }
+ else
+ {
+ mp_limb_t u1 = up[1];
+
+ /* we need to round (u1, u0, inex) */
+ mask = MPFR_LIMB_MASK(sh);
+ rb = u1 & (MPFR_LIMB_ONE << (sh - 1));
+ sb = ((u1 & mask) ^ rb) | up[0];
+ sp[0] = u1 & ~mask;
+ }
+
+ inex2 = inex * MPFR_SIGN(u);
+ MPFR_SIGN(s) = MPFR_SIGN(u);
+ MPFR_EXP(s) = MPFR_EXP(u);
+
+ /* in case inex2 > 0, the value of u is rounded away,
+ thus we need to subtract something from (u0, rb, sb):
+ (a) if sb is not zero, since the subtracted value is < 1, we can leave
+ sb as it is;
+ (b) if rb <> 0 and sb = 0: change to rb = 0 and sb = 1
+ (c) if rb = sb = 0: change to rb = 1 and sb = 1, and subtract 1 */
+ if (inex2 > 0)
+ {
+ if (rb && sb == 0)
+ {
+ rb = 0;
+ sb = 1;
+ }
+ }
+ else /* inex2 <= 0 */
+ sb |= inex;
+
+ /* now rb, sb are the round and sticky bits, together with the value of
+ sp[0], except possibly in the case rb = sb = 0 and inex2 > 0 */
+ if (rb == 0 && sb == 0)
+ {
+ if (inex2 <= 0)
+ MPFR_RET(0);
+ else /* inex2 > 0 can only occur for RNDN and RNDA:
+ RNDN: return sp[0] and inex
+ RNDA: return sp[0] and inex */
+ MPFR_RET(inex);
+ }
+ else if (rnd_mode == MPFR_RNDN)
+ {
+ if (rb == 0 || (sb == 0 && (sp[0] & (MPFR_LIMB_ONE << sh)) == 0))
+ goto truncate;
+ else
+ goto add_one_ulp;
+ }
+ else if (MPFR_IS_LIKE_RNDZ(rnd_mode, MPFR_IS_NEG(s)))
+ {
+ truncate:
+ MPFR_RET(-MPFR_SIGN(s));
+ }
+ else /* round away from zero */
+ {
+ add_one_ulp:
+ sp[0] += MPFR_LIMB_ONE << sh;
+ if (MPFR_UNLIKELY(sp[0] == 0))
+ {
+ sp[0] = MPFR_LIMB_HIGHBIT;
+ if (MPFR_EXP(s) + 1 <= __gmpfr_emax)
+ MPFR_SET_EXP (s, MPFR_EXP(s) + 1);
+ else /* overflow */
+ return mpfr_overflow (s, rnd_mode, MPFR_SIGN(s));
+ }
+ MPFR_RET(MPFR_SIGN(s));
+ }
+ }
+
+ /* general case PREC(s) >= GMP_NUMB_BITS */
+ inex2 = mpfr_set (s, u, rnd_mode);
+ return (rnd_mode != MPFR_RNDN) ? inex | inex2
+ : (inex2) ? inex2 : inex;
+}