From 7c6ef2f2142f0a4c22b5505d95553cac17867a21 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 20 Sep 2005 12:27:13 -0400 Subject: [PATCH] ARM optimized SHA1 implementation This is my ARM assembly SHA1 implementation for GIT. It is approximately 50% faster than the generic C version. On an XScale processor running at 400MHz: generic C version: 9.8 MB/s my version: 14.5 MB/s It's not that I expect a lot of big GIT users on ARM, but I stillknow about one important ARM user that might benefit from it, and writing that code was fun. I also reworked the makefile a bit so any optimized SHA1 implementations is used regardless of whether NO_OPENSSL is defined or not. Signed-off-by: Nicolas Pitre Signed-off-by: Junio C Hamano --- arm/sha1_arm.S | 184 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) create mode 100644 arm/sha1_arm.S (limited to 'arm/sha1_arm.S') diff --git a/arm/sha1_arm.S b/arm/sha1_arm.S new file mode 100644 index 0000000000..da92d20e84 --- /dev/null +++ b/arm/sha1_arm.S @@ -0,0 +1,184 @@ +/* + * SHA transform optimized for ARM + * + * Copyright: (C) 2005 by Nicolas Pitre + * Created: September 17, 2005 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + + .text + .globl sha_transform + +/* + * void sha_transform(uint32_t *hash, const unsigned char *data, uint32_t *W); + * + * note: the "data" pointer may be unaligned. + */ + +sha_transform: + + stmfd sp!, {r4 - r8, lr} + + @ for (i = 0; i < 16; i++) + @ W[i] = ntohl(((uint32_t *)data)[i]); */ + +#ifdef __ARMEB__ + mov r4, r0 + mov r0, r2 + mov r2, #64 + bl memcpy + mov r2, r0 + mov r0, r4 +#else + mov r3, r2 + mov lr, #16 +1: ldrb r4, [r1], #1 + ldrb r5, [r1], #1 + ldrb r6, [r1], #1 + ldrb r7, [r1], #1 + subs lr, lr, #1 + orr r5, r5, r4, lsl #8 + orr r6, r6, r5, lsl #8 + orr r7, r7, r6, lsl #8 + str r7, [r3], #4 + bne 1b +#endif + + @ for (i = 0; i < 64; i++) + @ W[i+16] = ror(W[i+13] ^ W[i+8] ^ W[i+2] ^ W[i], 31); + + sub r3, r2, #4 + mov lr, #64 +2: ldr r4, [r3, #4]! + subs lr, lr, #1 + ldr r5, [r3, #8] + ldr r6, [r3, #32] + ldr r7, [r3, #52] + eor r4, r4, r5 + eor r4, r4, r6 + eor r4, r4, r7 + mov r4, r4, ror #31 + str r4, [r3, #64] + bne 2b + + /* + * The SHA functions are: + * + * f1(B,C,D) = (D ^ (B & (C ^ D))) + * f2(B,C,D) = (B ^ C ^ D) + * f3(B,C,D) = ((B & C) | (D & (B | C))) + * + * Then the sub-blocks are processed as follows: + * + * A' = ror(A, 27) + f(B,C,D) + E + K + *W++ + * B' = A + * C' = ror(B, 2) + * D' = C + * E' = D + * + * We therefore unroll each loop 5 times to avoid register shuffling. + * Also the ror for C (and also D and E which are successivelyderived + * from it) is applied in place to cut on an additional mov insn for + * each round. + */ + + .macro sha_f1, A, B, C, D, E + ldr r3, [r2], #4 + eor ip, \C, \D + add \E, r1, \E, ror #2 + and ip, \B, ip, ror #2 + add \E, \E, \A, ror #27 + eor ip, ip, \D, ror #2 + add \E, \E, r3 + add \E, \E, ip + .endm + + .macro sha_f2, A, B, C, D, E + ldr r3, [r2], #4 + add \E, r1, \E, ror #2 + eor ip, \B, \C, ror #2 + add \E, \E, \A, ror #27 + eor ip, ip, \D, ror #2 + add \E, \E, r3 + add \E, \E, ip + .endm + + .macro sha_f3, A, B, C, D, E + ldr r3, [r2], #4 + add \E, r1, \E, ror #2 + orr ip, \B, \C, ror #2 + add \E, \E, \A, ror #27 + and ip, ip, \D, ror #2 + add \E, \E, r3 + and r3, \B, \C, ror #2 + orr ip, ip, r3 + add \E, \E, ip + .endm + + ldmia r0, {r4 - r8} + + mov lr, #4 + ldr r1, .L_sha_K + 0 + + /* adjust initial values */ + mov r6, r6, ror #30 + mov r7, r7, ror #30 + mov r8, r8, ror #30 + +3: subs lr, lr, #1 + sha_f1 r4, r5, r6, r7, r8 + sha_f1 r8, r4, r5, r6, r7 + sha_f1 r7, r8, r4, r5, r6 + sha_f1 r6, r7, r8, r4, r5 + sha_f1 r5, r6, r7, r8, r4 + bne 3b + + ldr r1, .L_sha_K + 4 + mov lr, #4 + +4: subs lr, lr, #1 + sha_f2 r4, r5, r6, r7, r8 + sha_f2 r8, r4, r5, r6, r7 + sha_f2 r7, r8, r4, r5, r6 + sha_f2 r6, r7, r8, r4, r5 + sha_f2 r5, r6, r7, r8, r4 + bne 4b + + ldr r1, .L_sha_K + 8 + mov lr, #4 + +5: subs lr, lr, #1 + sha_f3 r4, r5, r6, r7, r8 + sha_f3 r8, r4, r5, r6, r7 + sha_f3 r7, r8, r4, r5, r6 + sha_f3 r6, r7, r8, r4, r5 + sha_f3 r5, r6, r7, r8, r4 + bne 5b + + ldr r1, .L_sha_K + 12 + mov lr, #4 + +6: subs lr, lr, #1 + sha_f2 r4, r5, r6, r7, r8 + sha_f2 r8, r4, r5, r6, r7 + sha_f2 r7, r8, r4, r5, r6 + sha_f2 r6, r7, r8, r4, r5 + sha_f2 r5, r6, r7, r8, r4 + bne 6b + + ldmia r0, {r1, r2, r3, ip, lr} + add r4, r1, r4 + add r5, r2, r5 + add r6, r3, r6, ror #2 + add r7, ip, r7, ror #2 + add r8, lr, r8, ror #2 + stmia r0, {r4 - r8} + + ldmfd sp!, {r4 - r8, pc} + +.L_sha_K: + .word 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6 + -- cgit v1.2.3