1 -> BITS_PER_MP_LIMB

1 << (BITS_PER_MP_LIMB - 1) -> MP_LIMB_T_HIGHBIT


git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@1501 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 23 insertions, 22 deletions

diff --git a/add_ulp.c b/add_ulp.c
index d94fd73b6..1c0c695b1 100644
--- a/add_ulp.c
+++ b/add_ulp.c
@@ -26,23 +26,21 @@ MA 02111-1307, USA. */
 
 /* sets x to x+sign(x)*2^(MPFR_EXP(x)-MPFR_PREC(x)) */
 void
-#if __STDC__
-mpfr_add_one_ulp(mpfr_ptr x)
-#else
-mpfr_add_one_ulp(x)
-     mpfr_ptr x; 
-#endif
+mpfr_add_one_ulp (mpfr_ptr x)
 {
-  int xn, sh; mp_limb_t *xp;
+  int xn, sh;
+  mp_limb_t *xp;
 
-  if (MPFR_IS_INF(x)) { return; }
-  xn = 1 + (MPFR_PREC(x)-1)/BITS_PER_MP_LIMB;
-  sh = xn*BITS_PER_MP_LIMB - MPFR_PREC(x);
+  if (MPFR_IS_INF(x))
+    return;
+
+  xn = 1 + (MPFR_PREC(x) - 1) / BITS_PER_MP_LIMB;
+  sh = xn * BITS_PER_MP_LIMB - MPFR_PREC(x);
   xp = MPFR_MANT(x);
-  if (mpn_add_1(xp, xp, xn, (mp_limb_t)1<<sh)) {
-    MPFR_EXP(x)++;
-    mpn_rshift(xp, xp, xn, 1);
-    xp[xn-1] += (mp_limb_t)1<<(BITS_PER_MP_LIMB-1);
+  if (mpn_add_1 (xp, xp, xn, MP_LIMB_T_ONE << sh)) /* got 1.0000... */
+    {
+      MPFR_EXP(x)++;
+      xp[xn-1] = MP_LIMB_T_HIGHBIT;
   }
   return;
 }
@@ -51,18 +49,21 @@ mpfr_add_one_ulp(x)
 void
 mpfr_sub_one_ulp(mpfr_ptr x)
 {
-  int xn, sh; mp_limb_t *xp;
+  int xn, sh;
+  mp_limb_t *xp;
+
+  if (MPFR_IS_INF(x))
+    return;
 
-  if (MPFR_IS_INF(x)) { return; }
-  xn = 1 + (MPFR_PREC(x)-1)/BITS_PER_MP_LIMB;
-  sh = xn*BITS_PER_MP_LIMB-MPFR_PREC(x);
+  xn = 1 + (MPFR_PREC(x) - 1) / BITS_PER_MP_LIMB;
+  sh = xn * BITS_PER_MP_LIMB - MPFR_PREC(x);
   xp = MPFR_MANT(x);
-  mpn_sub_1(xp, xp, xn, (mp_limb_t)1<<sh);
-  if (xp[xn-1] >> (BITS_PER_MP_LIMB-1) == 0) {
+  mpn_sub_1 (xp, xp, xn, MP_LIMB_T_ONE << sh);
+  if (xp[xn-1] >> (BITS_PER_MP_LIMB - 1) == 0) {
     /* was an exact power of two: not normalized any more */
     MPFR_EXP(x)--;
-    mpn_lshift(xp, xp, xn, 1);
-    *xp |= ((mp_limb_t)1 << sh);
+    mpn_lshift (xp, xp, xn, 1);
+    *xp |= MP_LIMB_T_ONE << sh;
   }
   return;
 }