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authorNicolas Pitre <nico@cam.org>2005-09-20 16:27:13 (GMT)
committerJunio C Hamano <junkio@cox.net>2005-09-21 01:10:00 (GMT)
commit7c6ef2f2142f0a4c22b5505d95553cac17867a21 (patch)
tree5eff144d174355bd17dc7b12d77af58202c46ea5 /arm
parentf1f0d0889e5557bc467490fdbd53f7b912503a33 (diff)
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[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 <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
Diffstat (limited to 'arm')
-rw-r--r--arm/sha1.c82
-rw-r--r--arm/sha1.h18
-rw-r--r--arm/sha1_arm.S184
3 files changed, 284 insertions, 0 deletions
diff --git a/arm/sha1.c b/arm/sha1.c
new file mode 100644
index 0000000..11b1a04
--- /dev/null
+++ b/arm/sha1.c
@@ -0,0 +1,82 @@
+/*
+ * SHA-1 implementation optimized for ARM
+ *
+ * Copyright: (C) 2005 by Nicolas Pitre <nico@cam.org>
+ * Created: September 17, 2005
+ */
+
+#include <string.h>
+#include "sha1.h"
+
+extern void sha_transform(uint32_t *hash, const unsigned char *data, uint32_t *W);
+
+void SHA1_Init(SHA_CTX *c)
+{
+ c->len = 0;
+ c->hash[0] = 0x67452301;
+ c->hash[1] = 0xefcdab89;
+ c->hash[2] = 0x98badcfe;
+ c->hash[3] = 0x10325476;
+ c->hash[4] = 0xc3d2e1f0;
+}
+
+void SHA1_Update(SHA_CTX *c, const void *p, unsigned long n)
+{
+ uint32_t workspace[80];
+ unsigned int partial;
+ unsigned long done;
+
+ partial = c->len & 0x3f;
+ c->len += n;
+ if ((partial + n) >= 64) {
+ if (partial) {
+ done = 64 - partial;
+ memcpy(c->buffer + partial, p, done);
+ sha_transform(c->hash, c->buffer, workspace);
+ partial = 0;
+ } else
+ done = 0;
+ while (n >= done + 64) {
+ sha_transform(c->hash, p + done, workspace);
+ done += 64;
+ }
+ } else
+ done = 0;
+ if (n - done)
+ memcpy(c->buffer + partial, p + done, n - done);
+}
+
+void SHA1_Final(unsigned char *hash, SHA_CTX *c)
+{
+ uint64_t bitlen;
+ uint32_t bitlen_hi, bitlen_lo;
+ unsigned int i, offset, padlen;
+ unsigned char bits[8];
+ static const unsigned char padding[64] = { 0x80, };
+
+ bitlen = c->len << 3;
+ offset = c->len & 0x3f;
+ padlen = ((offset < 56) ? 56 : (64 + 56)) - offset;
+ SHA1_Update(c, padding, padlen);
+
+ bitlen_hi = bitlen >> 32;
+ bitlen_lo = bitlen & 0xffffffff;
+ bits[0] = bitlen_hi >> 24;
+ bits[1] = bitlen_hi >> 16;
+ bits[2] = bitlen_hi >> 8;
+ bits[3] = bitlen_hi;
+ bits[4] = bitlen_lo >> 24;
+ bits[5] = bitlen_lo >> 16;
+ bits[6] = bitlen_lo >> 8;
+ bits[7] = bitlen_lo;
+ SHA1_Update(c, bits, 8);
+
+ for (i = 0; i < 5; i++) {
+ uint32_t v = c->hash[i];
+ hash[0] = v >> 24;
+ hash[1] = v >> 16;
+ hash[2] = v >> 8;
+ hash[3] = v;
+ hash += 4;
+ }
+}
diff --git a/arm/sha1.h b/arm/sha1.h
new file mode 100644
index 0000000..3952646
--- /dev/null
+++ b/arm/sha1.h
@@ -0,0 +1,18 @@
+/*
+ * SHA-1 implementation optimized for ARM
+ *
+ * Copyright: (C) 2005 by Nicolas Pitre <nico@cam.org>
+ * Created: September 17, 2005
+ */
+
+#include <stdint.h>
+
+typedef struct sha_context {
+ uint64_t len;
+ uint32_t hash[5];
+ unsigned char buffer[64];
+} SHA_CTX;
+
+void SHA1_Init(SHA_CTX *c);
+void SHA1_Update(SHA_CTX *c, const void *p, unsigned long n);
+void SHA1_Final(unsigned char *hash, SHA_CTX *c);
diff --git a/arm/sha1_arm.S b/arm/sha1_arm.S
new file mode 100644
index 0000000..da92d20
--- /dev/null
+++ b/arm/sha1_arm.S
@@ -0,0 +1,184 @@
+/*
+ * SHA transform optimized for ARM
+ *
+ * Copyright: (C) 2005 by Nicolas Pitre <nico@cam.org>
+ * 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
+