diff options
author | Jiri Kosina <jkosina@suse.cz> | 2012-02-03 23:12:42 +0100 |
---|---|---|
committer | Jiri Kosina <jkosina@suse.cz> | 2012-02-03 23:13:05 +0100 |
commit | 972c5ae961d6e5103e2b33d935cfa4145fd47140 (patch) | |
tree | 350b2a76b979ba8766c09838617df67ff330eca0 /lib/mpi/generic_mpih-mul3.c | |
parent | drivers/char: comment fix: CMOS RTC update code is now in kernel/time/ntp.c (diff) | |
parent | Merge tag 'kmemleak-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/c... (diff) | |
download | linux-972c5ae961d6e5103e2b33d935cfa4145fd47140.tar.xz linux-972c5ae961d6e5103e2b33d935cfa4145fd47140.zip |
Merge branch 'master' into for-next
Sync with Linus' tree to be able to apply patch to a newer
code (namely drivers/gpu/drm/gma500/psb_intel_lvds.c)
Diffstat (limited to 'lib/mpi/generic_mpih-mul3.c')
-rw-r--r-- | lib/mpi/generic_mpih-mul3.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/lib/mpi/generic_mpih-mul3.c b/lib/mpi/generic_mpih-mul3.c new file mode 100644 index 000000000000..f96df327be63 --- /dev/null +++ b/lib/mpi/generic_mpih-mul3.c @@ -0,0 +1,61 @@ +/* mpihelp-mul_3.c - MPI helper functions + * Copyright (C) 1994, 1996, 1997, 1998, 2001 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + * + * Note: This code is heavily based on the GNU MP Library. + * Actually it's the same code with only minor changes in the + * way the data is stored; this is to support the abstraction + * of an optional secure memory allocation which may be used + * to avoid revealing of sensitive data due to paging etc. + * The GNU MP Library itself is published under the LGPL; + * however I decided to publish this code under the plain GPL. + */ + +#include "mpi-internal.h" +#include "longlong.h" + +mpi_limb_t +mpihelp_submul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, + mpi_size_t s1_size, mpi_limb_t s2_limb) +{ + mpi_limb_t cy_limb; + mpi_size_t j; + mpi_limb_t prod_high, prod_low; + mpi_limb_t x; + + /* The loop counter and index J goes from -SIZE to -1. This way + * the loop becomes faster. */ + j = -s1_size; + res_ptr -= j; + s1_ptr -= j; + + cy_limb = 0; + do { + umul_ppmm(prod_high, prod_low, s1_ptr[j], s2_limb); + + prod_low += cy_limb; + cy_limb = (prod_low < cy_limb ? 1 : 0) + prod_high; + + x = res_ptr[j]; + prod_low = x - prod_low; + cy_limb += prod_low > x ? 1 : 0; + res_ptr[j] = prod_low; + } while (++j); + + return cy_limb; +} |