xref: /openbsd/lib/libcrypto/bn/arch/amd64/bn_arch.h (revision 72c7c57a)
1 /*	$OpenBSD: bn_arch.h,v 1.14 2024/03/26 06:09:25 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 #include <openssl/bn.h>
19 
20 #ifndef HEADER_BN_ARCH_H
21 #define HEADER_BN_ARCH_H
22 
23 #ifndef OPENSSL_NO_ASM
24 
25 #define HAVE_BN_ADD
26 #define HAVE_BN_ADD_WORDS
27 
28 #define HAVE_BN_DIV_WORDS
29 
30 #define HAVE_BN_MUL_ADD_WORDS
31 #define HAVE_BN_MUL_COMBA4
32 #define HAVE_BN_MUL_COMBA8
33 #define HAVE_BN_MUL_WORDS
34 
35 #define HAVE_BN_SQR
36 #define HAVE_BN_SQR_COMBA4
37 #define HAVE_BN_SQR_COMBA8
38 
39 #define HAVE_BN_SUB
40 #define HAVE_BN_SUB_WORDS
41 
42 #define HAVE_BN_WORD_CLZ
43 
44 #if defined(__GNUC__)
45 
46 #define HAVE_BN_DIV_REM_WORDS_INLINE
47 
48 static inline void
49 bn_div_rem_words_inline(BN_ULONG h, BN_ULONG l, BN_ULONG d, BN_ULONG *out_q,
50     BN_ULONG *out_r)
51 {
52 	BN_ULONG q, r;
53 
54 	/*
55 	 * Unsigned division of %rdx:%rax by d with quotient being stored in
56 	 * %rax and remainder in %rdx.
57 	 */
58 	__asm__ volatile ("divq %4"
59 	    : "=a"(q), "=d"(r)
60 	    : "d"(h), "a"(l), "rm"(d)
61 	    : "cc");
62 
63 	*out_q = q;
64 	*out_r = r;
65 }
66 
67 #define HAVE_BN_MULW
68 
69 static inline void
70 bn_mulw(BN_ULONG a, BN_ULONG b, BN_ULONG *out_r1, BN_ULONG *out_r0)
71 {
72 	BN_ULONG r1, r0;
73 
74 	/*
75 	 * Unsigned multiplication of %rax, with the double word result being
76 	 * stored in %rdx:%rax.
77 	 */
78 	__asm__ ("mulq %3"
79 	    : "=d"(r1), "=a"(r0)
80 	    : "a"(a), "rm"(b)
81 	    : "cc");
82 
83 	*out_r1 = r1;
84 	*out_r0 = r0;
85 }
86 
87 #define HAVE_BN_SUBW
88 
89 static inline void
90 bn_subw(BN_ULONG a, BN_ULONG b, BN_ULONG *out_borrow, BN_ULONG *out_r0)
91 {
92 	BN_ULONG borrow, r0;
93 
94 	__asm__ (
95 	    "subq   %3, %1 \n"
96 	    "setb   %b0 \n"
97 	    "and    $1, %0 \n"
98 	    : "=r"(borrow), "=r"(r0)
99 	    : "1"(a), "rm"(b)
100 	    : "cc");
101 
102 	*out_borrow = borrow;
103 	*out_r0 = r0;
104 }
105 
106 #endif /* __GNUC__ */
107 
108 #endif
109 #endif
110