diff options
Diffstat (limited to 'sub1.c')
| -rw-r--r-- | sub1.c | 8 |
1 files changed, 5 insertions, 3 deletions
@@ -392,13 +392,14 @@ mpfr_sub1 (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mp_rnd_t rnd_mode) inexact = 0; goto truncate; - sub_one_ulp: /* add one unit in last place to a */ + sub_one_ulp: /* sub one unit in last place to a */ mpn_sub_1 (ap, ap, an, MP_LIMB_T_ONE << sh); inexact = -1; goto end_of_sub; add_one_ulp: /* add one unit in last place to a */ - if (mpn_add_1 (ap, ap, an, MP_LIMB_T_ONE << sh)) /* result is a power of 2 */ + if (MPFR_UNLIKELY(mpn_add_1 (ap, ap, an, MP_LIMB_T_ONE << sh))) + /* result is a power of 2: 11111111111111 + 1 = 1000000000000000 */ { ap[an-1] = MPFR_LIMB_HIGHBIT; add_exp = 1; @@ -406,7 +407,8 @@ mpfr_sub1 (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mp_rnd_t rnd_mode) inexact = 1; /* result larger than exact value */ truncate: - if ((ap[an-1] >> (BITS_PER_MP_LIMB - 1)) == 0) /* case 1 - epsilon */ + if (MPFR_UNLIKELY((ap[an-1] >> (BITS_PER_MP_LIMB - 1)) == 0)) + /* case 1 - epsilon */ { ap[an-1] = MPFR_LIMB_HIGHBIT; add_exp = 1; |