1 /* mpn_addmul_1 -- multiply the S1_SIZE long limb vector pointed to by S1_PTR
2 by S2_LIMB, add the S1_SIZE least significant limbs of the product to the
3 limb vector pointed to by RES_PTR. Return the most significant limb of
4 the product, adjusted for carry-out from the addition.
6 Copyright (C) 1992, 1993, 1994, 1996 Free Software Foundation, Inc.
8 This file is part of the GNU MP Library.
10 The GNU MP Library is free software; you can redistribute it and/or modify
11 it under the terms of the GNU Library General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or (at your
13 option) any later version.
15 The GNU MP Library is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
17 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
18 License for more details.
20 You should have received a copy of the GNU Library General Public License
21 along with the GNU MP Library; see the file COPYING.LIB. If not, write to
22 the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
29 mpn_addmul_1 (res_ptr
, s1_ptr
, s1_size
, s2_limb
)
30 register mp_ptr res_ptr
;
31 register mp_srcptr s1_ptr
;
33 register mp_limb s2_limb
;
35 register mp_limb cy_limb
;
37 register mp_limb prod_high
, prod_low
;
40 /* The loop counter and index J goes from -SIZE to -1. This way
41 the loop becomes faster. */
44 /* Offset the base pointers to compensate for the negative indices. */
51 umul_ppmm (prod_high
, prod_low
, s1_ptr
[j
], s2_limb
);
54 cy_limb
= (prod_low
< cy_limb
) + prod_high
;
57 prod_low
= x
+ prod_low
;
58 cy_limb
+= (prod_low
< x
);
59 res_ptr
[j
] = prod_low
;