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Merge branch 'jc/sha1'

* jc/sha1:
  A better-scheduled PPC SHA-1 implementation.
  test-sha1: test hashing large buffer
  Makefile: add framework to verify and bench sha1 implementations.
This commit is contained in:
Junio C Hamano 2006-07-05 16:36:25 -07:00
commit b296990c3b
4 changed files with 319 additions and 144 deletions

View file

@ -651,6 +651,12 @@ test-delta$X: test-delta.c diff-delta.o patch-delta.o
test-dump-cache-tree$X: dump-cache-tree.o $(GITLIBS)
$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
test-sha1$X: test-sha1.o $(GITLIBS)
$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS)
check-sha1:: test-sha1$X
./test-sha1.sh
check:
for i in *.c; do sparse $(ALL_CFLAGS) $(SPARSE_FLAGS) $$i || exit; done

View file

@ -3,183 +3,222 @@
*
* Copyright (C) 2005 Paul Mackerras <paulus@samba.org>
*/
#define FS 80
/*
* We roll the registers for T, A, B, C, D, E around on each
* iteration; T on iteration t is A on iteration t+1, and so on.
* We use registers 7 - 12 for this.
* PowerPC calling convention:
* %r0 - volatile temp
* %r1 - stack pointer.
* %r2 - reserved
* %r3-%r12 - Incoming arguments & return values; volatile.
* %r13-%r31 - Callee-save registers
* %lr - Return address, volatile
* %ctr - volatile
*
* Register usage in this routine:
* %r0 - temp
* %r3 - argument (pointer to 5 words of SHA state)
* %r4 - argument (pointer to data to hash)
* %r5 - Contant K in SHA round (initially number of blocks to hash)
* %r6-%r10 - Working copies of SHA variables A..E (actually E..A order)
* %r11-%r26 - Data being hashed W[].
* %r27-%r31 - Previous copies of A..E, for final add back.
* %ctr - loop count
*/
#define RT(t) ((((t)+5)%6)+7)
#define RA(t) ((((t)+4)%6)+7)
#define RB(t) ((((t)+3)%6)+7)
#define RC(t) ((((t)+2)%6)+7)
#define RD(t) ((((t)+1)%6)+7)
#define RE(t) ((((t)+0)%6)+7)
/* We use registers 16 - 31 for the W values */
#define W(t) (((t)%16)+16)
#define STEPD0(t) \
and %r6,RB(t),RC(t); \
andc %r0,RD(t),RB(t); \
rotlwi RT(t),RA(t),5; \
rotlwi RB(t),RB(t),30; \
or %r6,%r6,%r0; \
add %r0,RE(t),%r15; \
add RT(t),RT(t),%r6; \
add %r0,%r0,W(t); \
add RT(t),RT(t),%r0
/*
* We roll the registers for A, B, C, D, E around on each
* iteration; E on iteration t is D on iteration t+1, and so on.
* We use registers 6 - 10 for this. (Registers 27 - 31 hold
* the previous values.)
*/
#define RA(t) (((t)+4)%5+6)
#define RB(t) (((t)+3)%5+6)
#define RC(t) (((t)+2)%5+6)
#define RD(t) (((t)+1)%5+6)
#define RE(t) (((t)+0)%5+6)
/* We use registers 11 - 26 for the W values */
#define W(t) ((t)%16+11)
/* Register 5 is used for the constant k */
/*
* The basic SHA-1 round function is:
* E += ROTL(A,5) + F(B,C,D) + W[i] + K; B = ROTL(B,30)
* Then the variables are renamed: (A,B,C,D,E) = (E,A,B,C,D).
*
* Every 20 rounds, the function F() and the contant K changes:
* - 20 rounds of f0(b,c,d) = "bit wise b ? c : d" = (^b & d) + (b & c)
* - 20 rounds of f1(b,c,d) = b^c^d = (b^d)^c
* - 20 rounds of f2(b,c,d) = majority(b,c,d) = (b&d) + ((b^d)&c)
* - 20 more rounds of f1(b,c,d)
*
* These are all scheduled for near-optimal performance on a G4.
* The G4 is a 3-issue out-of-order machine with 3 ALUs, but it can only
* *consider* starting the oldest 3 instructions per cycle. So to get
* maximum performace out of it, you have to treat it as an in-order
* machine. Which means interleaving the computation round t with the
* computation of W[t+4].
*
* The first 16 rounds use W values loaded directly from memory, while the
* remianing 64 use values computed from those first 16. We preload
* 4 values before starting, so there are three kinds of rounds:
* - The first 12 (all f0) also load the W values from memory.
* - The next 64 compute W(i+4) in parallel. 8*f0, 20*f1, 20*f2, 16*f1.
* - The last 4 (all f1) do not do anything with W.
*
* Therefore, we have 6 different round functions:
* STEPD0_LOAD(t,s) - Perform round t and load W(s). s < 16
* STEPD0_UPDATE(t,s) - Perform round t and compute W(s). s >= 16.
* STEPD1_UPDATE(t,s)
* STEPD2_UPDATE(t,s)
* STEPD1(t) - Perform round t with no load or update.
*
* The G5 is more fully out-of-order, and can find the parallelism
* by itself. The big limit is that it has a 2-cycle ALU latency, so
* even though it's 2-way, the code has to be scheduled as if it's
* 4-way, which can be a limit. To help it, we try to schedule the
* read of RA(t) as late as possible so it doesn't stall waiting for
* the previous round's RE(t-1), and we try to rotate RB(t) as early
* as possible while reading RC(t) (= RB(t-1)) as late as possible.
*/
/* the initial loads. */
#define LOADW(s) \
lwz W(s),(s)*4(%r4)
/*
* Perform a step with F0, and load W(s). Uses W(s) as a temporary
* before loading it.
* This is actually 10 instructions, which is an awkward fit.
* It can execute grouped as listed, or delayed one instruction.
* (If delayed two instructions, there is a stall before the start of the
* second line.) Thus, two iterations take 7 cycles, 3.5 cycles per round.
*/
#define STEPD0_LOAD(t,s) \
add RE(t),RE(t),W(t); andc %r0,RD(t),RB(t); and W(s),RC(t),RB(t); \
add RE(t),RE(t),%r0; rotlwi %r0,RA(t),5; rotlwi RB(t),RB(t),30; \
add RE(t),RE(t),W(s); add %r0,%r0,%r5; lwz W(s),(s)*4(%r4); \
add RE(t),RE(t),%r0
/*
* This is likewise awkward, 13 instructions. However, it can also
* execute starting with 2 out of 3 possible moduli, so it does 2 rounds
* in 9 cycles, 4.5 cycles/round.
*/
#define STEPD0_UPDATE(t,s,loadk...) \
add RE(t),RE(t),W(t); andc %r0,RD(t),RB(t); xor W(s),W((s)-16),W((s)-3); \
add RE(t),RE(t),%r0; and %r0,RC(t),RB(t); xor W(s),W(s),W((s)-8); \
add RE(t),RE(t),%r0; rotlwi %r0,RA(t),5; xor W(s),W(s),W((s)-14); \
add RE(t),RE(t),%r5; loadk; rotlwi RB(t),RB(t),30; rotlwi W(s),W(s),1; \
add RE(t),RE(t),%r0
/* Nicely optimal. Conveniently, also the most common. */
#define STEPD1_UPDATE(t,s,loadk...) \
add RE(t),RE(t),W(t); xor %r0,RD(t),RB(t); xor W(s),W((s)-16),W((s)-3); \
add RE(t),RE(t),%r5; loadk; xor %r0,%r0,RC(t); xor W(s),W(s),W((s)-8); \
add RE(t),RE(t),%r0; rotlwi %r0,RA(t),5; xor W(s),W(s),W((s)-14); \
add RE(t),RE(t),%r0; rotlwi RB(t),RB(t),30; rotlwi W(s),W(s),1
/*
* The naked version, no UPDATE, for the last 4 rounds. 3 cycles per.
* We could use W(s) as a temp register, but we don't need it.
*/
#define STEPD1(t) \
xor %r6,RB(t),RC(t); \
rotlwi RT(t),RA(t),5; \
rotlwi RB(t),RB(t),30; \
xor %r6,%r6,RD(t); \
add %r0,RE(t),%r15; \
add RT(t),RT(t),%r6; \
add %r0,%r0,W(t); \
add RT(t),RT(t),%r0
add RE(t),RE(t),W(t); xor %r0,RD(t),RB(t); \
rotlwi RB(t),RB(t),30; add RE(t),RE(t),%r5; xor %r0,%r0,RC(t); \
add RE(t),RE(t),%r0; rotlwi %r0,RA(t),5; /* spare slot */ \
add RE(t),RE(t),%r0
#define STEPD2(t) \
and %r6,RB(t),RC(t); \
and %r0,RB(t),RD(t); \
rotlwi RT(t),RA(t),5; \
rotlwi RB(t),RB(t),30; \
or %r6,%r6,%r0; \
and %r0,RC(t),RD(t); \
or %r6,%r6,%r0; \
add %r0,RE(t),%r15; \
add RT(t),RT(t),%r6; \
add %r0,%r0,W(t); \
add RT(t),RT(t),%r0
/*
* 14 instructions, 5 cycles per. The majority function is a bit
* awkward to compute. This can execute with a 1-instruction delay,
* but it causes a 2-instruction delay, which triggers a stall.
*/
#define STEPD2_UPDATE(t,s,loadk...) \
add RE(t),RE(t),W(t); and %r0,RD(t),RB(t); xor W(s),W((s)-16),W((s)-3); \
add RE(t),RE(t),%r0; xor %r0,RD(t),RB(t); xor W(s),W(s),W((s)-8); \
add RE(t),RE(t),%r5; loadk; and %r0,%r0,RC(t); xor W(s),W(s),W((s)-14); \
add RE(t),RE(t),%r0; rotlwi %r0,RA(t),5; rotlwi W(s),W(s),1; \
add RE(t),RE(t),%r0; rotlwi RB(t),RB(t),30
#define LOADW(t) \
lwz W(t),(t)*4(%r4)
#define STEP0_LOAD4(t,s) \
STEPD0_LOAD(t,s); \
STEPD0_LOAD((t+1),(s)+1); \
STEPD0_LOAD((t)+2,(s)+2); \
STEPD0_LOAD((t)+3,(s)+3)
#define UPDATEW(t) \
xor %r0,W((t)-3),W((t)-8); \
xor W(t),W((t)-16),W((t)-14); \
xor W(t),W(t),%r0; \
rotlwi W(t),W(t),1
#define STEPUP4(fn, t, s, loadk...) \
STEP##fn##_UPDATE(t,s,); \
STEP##fn##_UPDATE((t)+1,(s)+1,); \
STEP##fn##_UPDATE((t)+2,(s)+2,); \
STEP##fn##_UPDATE((t)+3,(s)+3,loadk)
#define STEP0LD4(t) \
STEPD0(t); LOADW((t)+4); \
STEPD0((t)+1); LOADW((t)+5); \
STEPD0((t)+2); LOADW((t)+6); \
STEPD0((t)+3); LOADW((t)+7)
#define STEPUP4(t, fn) \
STEP##fn(t); UPDATEW((t)+4); \
STEP##fn((t)+1); UPDATEW((t)+5); \
STEP##fn((t)+2); UPDATEW((t)+6); \
STEP##fn((t)+3); UPDATEW((t)+7)
#define STEPUP20(t, fn) \
STEPUP4(t, fn); \
STEPUP4((t)+4, fn); \
STEPUP4((t)+8, fn); \
STEPUP4((t)+12, fn); \
STEPUP4((t)+16, fn)
#define STEPUP20(fn, t, s, loadk...) \
STEPUP4(fn, t, s,); \
STEPUP4(fn, (t)+4, (s)+4,); \
STEPUP4(fn, (t)+8, (s)+8,); \
STEPUP4(fn, (t)+12, (s)+12,); \
STEPUP4(fn, (t)+16, (s)+16, loadk)
.globl sha1_core
sha1_core:
stwu %r1,-FS(%r1)
stw %r15,FS-68(%r1)
stw %r16,FS-64(%r1)
stw %r17,FS-60(%r1)
stw %r18,FS-56(%r1)
stw %r19,FS-52(%r1)
stw %r20,FS-48(%r1)
stw %r21,FS-44(%r1)
stw %r22,FS-40(%r1)
stw %r23,FS-36(%r1)
stw %r24,FS-32(%r1)
stw %r25,FS-28(%r1)
stw %r26,FS-24(%r1)
stw %r27,FS-20(%r1)
stw %r28,FS-16(%r1)
stw %r29,FS-12(%r1)
stw %r30,FS-8(%r1)
stw %r31,FS-4(%r1)
stwu %r1,-80(%r1)
stmw %r13,4(%r1)
/* Load up A - E */
lwz RA(0),0(%r3) /* A */
lwz RB(0),4(%r3) /* B */
lwz RC(0),8(%r3) /* C */
lwz RD(0),12(%r3) /* D */
lwz RE(0),16(%r3) /* E */
lmw %r27,0(%r3)
mtctr %r5
1: LOADW(0)
1:
LOADW(0)
lis %r5,0x5a82
mr RE(0),%r31
LOADW(1)
mr RD(0),%r30
mr RC(0),%r29
LOADW(2)
ori %r5,%r5,0x7999 /* K0-19 */
mr RB(0),%r28
LOADW(3)
mr RA(0),%r27
lis %r15,0x5a82 /* K0-19 */
ori %r15,%r15,0x7999
STEP0LD4(0)
STEP0LD4(4)
STEP0LD4(8)
STEPUP4(12, D0)
STEPUP4(16, D0)
STEP0_LOAD4(0, 4)
STEP0_LOAD4(4, 8)
STEP0_LOAD4(8, 12)
STEPUP4(D0, 12, 16,)
STEPUP4(D0, 16, 20, lis %r5,0x6ed9)
lis %r15,0x6ed9 /* K20-39 */
ori %r15,%r15,0xeba1
STEPUP20(20, D1)
ori %r5,%r5,0xeba1 /* K20-39 */
STEPUP20(D1, 20, 24, lis %r5,0x8f1b)
lis %r15,0x8f1b /* K40-59 */
ori %r15,%r15,0xbcdc
STEPUP20(40, D2)
ori %r5,%r5,0xbcdc /* K40-59 */
STEPUP20(D2, 40, 44, lis %r5,0xca62)
lis %r15,0xca62 /* K60-79 */
ori %r15,%r15,0xc1d6
STEPUP4(60, D1)
STEPUP4(64, D1)
STEPUP4(68, D1)
STEPUP4(72, D1)
ori %r5,%r5,0xc1d6 /* K60-79 */
STEPUP4(D1, 60, 64,)
STEPUP4(D1, 64, 68,)
STEPUP4(D1, 68, 72,)
STEPUP4(D1, 72, 76,)
addi %r4,%r4,64
STEPD1(76)
STEPD1(77)
STEPD1(78)
STEPD1(79)
lwz %r20,16(%r3)
lwz %r19,12(%r3)
lwz %r18,8(%r3)
lwz %r17,4(%r3)
lwz %r16,0(%r3)
add %r20,RE(80),%r20
add RD(0),RD(80),%r19
add RC(0),RC(80),%r18
add RB(0),RB(80),%r17
add RA(0),RA(80),%r16
mr RE(0),%r20
stw RA(0),0(%r3)
stw RB(0),4(%r3)
stw RC(0),8(%r3)
stw RD(0),12(%r3)
stw RE(0),16(%r3)
/* Add results to original values */
add %r31,%r31,RE(0)
add %r30,%r30,RD(0)
add %r29,%r29,RC(0)
add %r28,%r28,RB(0)
add %r27,%r27,RA(0)
addi %r4,%r4,64
bdnz 1b
lwz %r15,FS-68(%r1)
lwz %r16,FS-64(%r1)
lwz %r17,FS-60(%r1)
lwz %r18,FS-56(%r1)
lwz %r19,FS-52(%r1)
lwz %r20,FS-48(%r1)
lwz %r21,FS-44(%r1)
lwz %r22,FS-40(%r1)
lwz %r23,FS-36(%r1)
lwz %r24,FS-32(%r1)
lwz %r25,FS-28(%r1)
lwz %r26,FS-24(%r1)
lwz %r27,FS-20(%r1)
lwz %r28,FS-16(%r1)
lwz %r29,FS-12(%r1)
lwz %r30,FS-8(%r1)
lwz %r31,FS-4(%r1)
addi %r1,%r1,FS
/* Save final hash, restore registers, and return */
stmw %r27,0(%r3)
lmw %r13,4(%r1)
addi %r1,%r1,80
blr

47
test-sha1.c Normal file
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@ -0,0 +1,47 @@
#include "cache.h"
int main(int ac, char **av)
{
SHA_CTX ctx;
unsigned char sha1[20];
unsigned bufsz = 8192;
char *buffer;
if (ac == 2)
bufsz = strtoul(av[1], NULL, 10) * 1024 * 1024;
if (!bufsz)
bufsz = 8192;
while ((buffer = malloc(bufsz)) == NULL) {
fprintf(stderr, "bufsz %u is too big, halving...\n", bufsz);
bufsz /= 2;
if (bufsz < 1024)
die("OOPS");
}
SHA1_Init(&ctx);
while (1) {
ssize_t sz, this_sz;
char *cp = buffer;
unsigned room = bufsz;
this_sz = 0;
while (room) {
sz = xread(0, cp, room);
if (sz == 0)
break;
if (sz < 0)
die("test-sha1: %s", strerror(errno));
this_sz += sz;
cp += sz;
room -= sz;
}
if (this_sz == 0)
break;
SHA1_Update(&ctx, buffer, this_sz);
}
SHA1_Final(sha1, &ctx);
puts(sha1_to_hex(sha1));
exit(0);
}

83
test-sha1.sh Executable file
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@ -0,0 +1,83 @@
#!/bin/sh
dd if=/dev/zero bs=1048576 count=100 2>/dev/null |
/usr/bin/time ./test-sha1 >/dev/null
while read expect cnt pfx
do
case "$expect" in '#'*) continue ;; esac
actual=`
{
test -z "$pfx" || echo "$pfx"
dd if=/dev/zero bs=1048576 count=$cnt 2>/dev/null |
tr '[\0]' '[g]'
} | ./test-sha1 $cnt
`
if test "$expect" = "$actual"
then
echo "OK: $expect $cnt $pfx"
else
echo >&2 "OOPS: $cnt"
echo >&2 "expect: $expect"
echo >&2 "actual: $actual"
exit 1
fi
done <<EOF
da39a3ee5e6b4b0d3255bfef95601890afd80709 0
3f786850e387550fdab836ed7e6dc881de23001b 0 a
5277cbb45a15902137d332d97e89cf8136545485 0 ab
03cfd743661f07975fa2f1220c5194cbaff48451 0 abc
3330b4373640f9e4604991e73c7e86bfd8da2dc3 0 abcd
ec11312386ad561674f724b8cca7cf1796e26d1d 0 abcde
bdc37c074ec4ee6050d68bc133c6b912f36474df 0 abcdef
69bca99b923859f2dc486b55b87f49689b7358c7 0 abcdefg
e414af7161c9554089f4106d6f1797ef14a73666 0 abcdefgh
0707f2970043f9f7c22029482db27733deaec029 0 abcdefghi
a4dd8aa74a5636728fe52451636e2e17726033aa 1
9986b45e2f4d7086372533bb6953a8652fa3644a 1 frotz
23d8d4f788e8526b4877548a32577543cbaaf51f 10
8cd23f822ab44c7f481b8c92d591f6d1fcad431c 10 frotz
f3b5604a4e604899c1233edb3bf1cc0ede4d8c32 512
b095bd837a371593048136e429e9ac4b476e1bb3 512 frotz
08fa81d6190948de5ccca3966340cc48c10cceac 1200 xyzzy
e33a291f42c30a159733dd98b8b3e4ff34158ca0 4090 4G
#a3bf783bc20caa958f6cb24dd140a7b21984838d 9999 nitfol
EOF
exit
# generating test vectors
# inputs are number of megabytes followed by some random string to prefix.
while read cnt pfx
do
actual=`
{
test -z "$pfx" || echo "$pfx"
dd if=/dev/zero bs=1048576 count=$cnt 2>/dev/null |
tr '[\0]' '[g]'
} | sha1sum |
sed -e 's/ .*//'
`
echo "$actual $cnt $pfx"
done <<EOF
0
0 a
0 ab
0 abc
0 abcd
0 abcde
0 abcdef
0 abcdefg
0 abcdefgh
0 abcdefghi
1
1 frotz
10
10 frotz
512
512 frotz
1200 xyzzy
4090 4G
9999 nitfol
EOF