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Subject[20/28] crypto: sha512 - Use binary and instead of modulus
3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Herbert Xu <herbert@gondor.apana.org.au>

commit 58d7d18b5268febb8b1391c6dffc8e2aaa751fcd upstream.

The previous patch used the modulus operator over a power of 2
unnecessarily which may produce suboptimal binary code. This
patch changes changes them to binary ands instead.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
crypto/sha512_generic.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/crypto/sha512_generic.c
+++ b/crypto/sha512_generic.c
@@ -78,7 +78,7 @@ static inline void LOAD_OP(int I, u64 *W

static inline void BLEND_OP(int I, u64 *W)
{
- W[I % 16] += s1(W[(I-2) % 16]) + W[(I-7) % 16] + s0(W[(I-15) % 16]);
+ W[I & 15] += s1(W[(I-2) & 15]) + W[(I-7) & 15] + s0(W[(I-15) & 15]);
}

static void
@@ -105,7 +105,7 @@ sha512_transform(u64 *state, const u8 *i

#define SHA512_16_79(i, a, b, c, d, e, f, g, h) \
BLEND_OP(i, W); \
- t1 = h + e1(e) + Ch(e, f, g) + sha512_K[i] + W[(i)%16]; \
+ t1 = h + e1(e) + Ch(e, f, g) + sha512_K[i] + W[(i)&15]; \
t2 = e0(a) + Maj(a, b, c); \
d += t1; \
h = t1 + t2



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