1 /* $OpenBSD: bn_arch.h,v 1.4 2023/02/16 10:41:03 jsing Exp $ */ 2 /* 3 * Copyright (c) 2023 Joel Sing <jsing@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #ifndef HEADER_BN_ARCH_H 19 #define HEADER_BN_ARCH_H 20 21 #ifndef OPENSSL_NO_ASM 22 23 #if 0 /* Needs testing and enabling. */ 24 #if defined(__GNUC__) 25 #define HAVE_BN_MULW 26 27 static inline void 28 bn_mulw(BN_ULONG a, BN_ULONG b, BN_ULONG *out_r1, BN_ULONG *out_r0) 29 { 30 BN_ULONG r1, r0; 31 32 /* Unsigned multiplication using a mulhdu/mul pair. */ 33 __asm__ ("mulhdu %0, %2, %3; mul %1, %2, %3" 34 : "=&r"(r1), "=r"(r0) 35 : "r"(a), "r"(b)); 36 37 *out_r1 = r1; 38 *out_r0 = r0; 39 } 40 #endif /* __GNUC__ */ 41 #endif 42 43 #endif 44 #endif 45