bootstrap.c: Use clrbit and roinit.

1 files changed, 6 insertions, 10 deletions

diff --git a/bootstrap.c b/bootstrap.c
index bff960ed8..11affac00 100644
--- a/bootstrap.c
+++ b/bootstrap.c
@@ -1,6 +1,6 @@
 /* Functions needed for bootstrapping the gmp build, based on mini-gmp.
 
-Copyright 2001, 2002, 2004, 2011, 2012 Free Software Foundation, Inc.
+Copyright 2001, 2002, 2004, 2011, 2012, 2015 Free Software Foundation, Inc.
 
 This file is part of the GNU MP Library.
 
@@ -88,7 +88,7 @@ log2_ceil (int n)
 /* Set inv to the inverse of d, in the style of invert_limb, ie. for
    udiv_qrnnd_preinv.  */
 void
-mpz_preinv_invert (mpz_t inv, mpz_t d, int numb_bits)
+mpz_preinv_invert (mpz_t inv, const mpz_t d, int numb_bits)
 {
   mpz_t  t;
   int    norm;
@@ -99,16 +99,14 @@ mpz_preinv_invert (mpz_t inv, mpz_t d, int numb_bits)
   mpz_init_set_ui (t, 1L);
   mpz_mul_2exp (t, t, 2*numb_bits - norm);
   mpz_tdiv_q (inv, t, d);
-  mpz_set_ui (t, 1L);
-  mpz_mul_2exp (t, t, numb_bits);
-  mpz_sub (inv, inv, t);
+  mpz_clrbit (inv, numb_bits);
 
   mpz_clear (t);
 }
 
 /* Calculate r satisfying r*d == 1 mod 2^n. */
 void
-mpz_invert_2exp (mpz_t r, mpz_t a, unsigned long n)
+mpz_invert_2exp (mpz_t r, const mpz_t a, unsigned long n)
 {
   unsigned long  i;
   mpz_t  inv, prod;
@@ -137,10 +135,8 @@ mpz_invert_2exp (mpz_t r, mpz_t a, unsigned long n)
 
 /* Calculate inv satisfying r*a == 1 mod 2^n. */
 void
-mpz_invert_ui_2exp (mpz_t r, unsigned long a, unsigned long n)
+mpz_invert_ui_2exp (mpz_t r, mp_limb_t a, unsigned long n)
 {
   mpz_t  az;
-  mpz_init_set_ui (az, a);
-  mpz_invert_2exp (r, az, n);
-  mpz_clear (az);
+  mpz_invert_2exp (r, mpz_roinit_n (az, &a, 1), n);
 }