Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /* mpihelp-add_2.c  -  MPI helper functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Copyright (C) 1994, 1996, 1997, 1998, 2001 Free Software Foundation, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * This file is part of GnuPG.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  * Note: This code is heavily based on the GNU MP Library.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  *	 Actually it's the same code with only minor changes in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  *	 way the data is stored; this is to support the abstraction
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  *	 of an optional secure memory allocation which may be used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  *	 to avoid revealing of sensitive data due to paging etc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  *	 The GNU MP Library itself is published under the LGPL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)  *	 however I decided to publish this code under the plain GPL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include "mpi-internal.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include "longlong.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) mpi_limb_t
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) mpihelp_sub_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	      mpi_ptr_t s2_ptr, mpi_size_t size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	mpi_limb_t x, y, cy;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 	mpi_size_t j;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	/* The loop counter and index J goes from -SIZE to -1.  This way
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	   the loop becomes faster.  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	j = -size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	/* Offset the base pointers to compensate for the negative indices.  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	s1_ptr -= j;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	s2_ptr -= j;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	res_ptr -= j;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	cy = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 		y = s2_ptr[j];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 		x = s1_ptr[j];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 		y += cy;	/* add previous carry to subtrahend */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		cy = y < cy;	/* get out carry from that addition */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 		y = x - y;	/* main subtract */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 		cy += y > x;	/* get out carry from the subtract, combine */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 		res_ptr[j] = y;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	} while (++j);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	return cy;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) }