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sha3: remove two "small code" codepaths: I can't reproduce code size win on them anymore

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2013-01-15 22:07:48 +01:00
parent 8e7312e12f
commit 8fb3ab528e
1 changed files with 18 additions and 43 deletions
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61
libbb/hash_md5_sha.c
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@ -977,14 +977,12 @@ static const uint8_t KECCAK_PI_LANE[25] = {
14, 22, 9, 6, 1 14, 22, 9, 6, 1
}; };
static const uint8_t MOD5[10] = {
0, 1, 2, 3, 4, 0, 1, 2, 3, 4
};
#define ARCH_IS_64BIT (sizeof(long) >= sizeof(uint64_t)) #define ARCH_IS_64BIT (sizeof(long) >= sizeof(uint64_t))
static void KeccakF(uint64_t *state) static void KeccakF(uint64_t *state)
{ {
/*static const uint8_t MOD5[10] = { 0, 1, 2, 3, 4, 0, 1, 2, 3, 4 };*/
unsigned x, y; unsigned x, y;
unsigned round; unsigned round;
@ -1009,18 +1007,11 @@ static void KeccakF(uint64_t *state)
*/ */
for (x = 0; x < 5; ++x) { for (x = 0; x < 5; ++x) {
uint64_t temp = BC[x + 4] ^ rotl64(BC[x + 1], 1); uint64_t temp = BC[x + 4] ^ rotl64(BC[x + 1], 1);
if (SHA3_SMALL && !ARCH_IS_64BIT) { state[x] ^= temp;
for (y = 0; y <= 20; y += 5) state[x + 5] ^= temp;
state[x + y] ^= temp; state[x + 10] ^= temp;
} else { state[x + 15] ^= temp;
/* On 64-bit, this is also smaller, state[x + 20] ^= temp;
* not only faster, than loop */
state[x] ^= temp;
state[x + 5] ^= temp;
state[x + 10] ^= temp;
state[x + 15] ^= temp;
state[x + 20] ^= temp;
}
} }
} }
@ -1057,33 +1048,17 @@ static void KeccakF(uint64_t *state)
/* Chi */ /* Chi */
for (y = 0; y <= 20; y += 5) { for (y = 0; y <= 20; y += 5) {
if (SHA3_SMALL && !ARCH_IS_64BIT) { uint64_t BC0, BC1, BC2, BC3, BC4;
uint64_t BC[5]; BC0 = state[y + 0];
BC[0] = state[y + 0]; BC1 = state[y + 1];
BC[1] = state[y + 1]; BC2 = state[y + 2];
BC[2] = state[y + 2]; state[y + 0] = BC0 ^ ((~BC1) & BC2);
BC[3] = state[y + 3]; BC3 = state[y + 3];
BC[4] = state[y + 4]; state[y + 1] = BC1 ^ ((~BC2) & BC3);
for (x = 0; x < 5; ++x) { BC4 = state[y + 4];
state[y + x] = state[y + 2] = BC2 ^ ((~BC3) & BC4);
BC[x] ^ ((~BC[MOD5[x + 1]]) & state[y + 3] = BC3 ^ ((~BC4) & BC0);
BC[MOD5[x + 2]]); state[y + 4] = BC4 ^ ((~BC0) & BC1);
}
} else {
/* 32-bit x86: +50 bytes code, 10% faster */
/* 64-bit x86: ~same code size, 30% faster */
uint64_t BC0, BC1, BC2, BC3, BC4;
BC0 = state[y + 0];
BC1 = state[y + 1];
BC2 = state[y + 2];
state[y + 0] = BC0 ^ ((~BC1) & BC2);
BC3 = state[y + 3];
state[y + 1] = BC1 ^ ((~BC2) & BC3);
BC4 = state[y + 4];
state[y + 2] = BC2 ^ ((~BC3) & BC4);
state[y + 3] = BC3 ^ ((~BC4) & BC0);
state[y + 4] = BC4 ^ ((~BC0) & BC1);
}
} }
/* Iota */ /* Iota */