diff options
| author | Denis Vlasenko <vda@ilport.com.ua> | 2005-11-29 22:23:20 +1100 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-01-09 14:15:51 -0800 |
| commit | e6a3a925a25ddd2ebd66dbc8d14ebdd3d57ca0c3 (patch) | |
| tree | 1b13c0cd7da01e4a7c14cdae1231ca22d317df21 | |
| parent | 827c3911d8551842900f44c9a139382bcae68e6e (diff) | |
[CRYPTO] aes-i586: Nano-optimisation on key length check
Reduce the number of comparisons by one through the use of jb/je.
This patch also corrects the comments regarding the different key
lengths.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
| -rw-r--r-- | arch/i386/crypto/aes-i586-asm.S | 40 |
1 files changed, 19 insertions, 21 deletions
diff --git a/arch/i386/crypto/aes-i586-asm.S b/arch/i386/crypto/aes-i586-asm.S index 7b73c67cb4e8..911b15377f2e 100644 --- a/arch/i386/crypto/aes-i586-asm.S +++ b/arch/i386/crypto/aes-i586-asm.S @@ -255,18 +255,17 @@ aes_enc_blk: xor 8(%ebp),%r4 xor 12(%ebp),%r5 - sub $8,%esp // space for register saves on stack - add $16,%ebp // increment to next round key - sub $10,%r3 - je 4f // 10 rounds for 128-bit key - add $32,%ebp - sub $2,%r3 - je 3f // 12 rounds for 128-bit key - add $32,%ebp - -2: fwd_rnd1( -64(%ebp) ,ft_tab) // 14 rounds for 128-bit key + sub $8,%esp // space for register saves on stack + add $16,%ebp // increment to next round key + cmp $12,%r3 + jb 4f // 10 rounds for 128-bit key + lea 32(%ebp),%ebp + je 3f // 12 rounds for 192-bit key + lea 32(%ebp),%ebp + +2: fwd_rnd1( -64(%ebp) ,ft_tab) // 14 rounds for 256-bit key fwd_rnd2( -48(%ebp) ,ft_tab) -3: fwd_rnd1( -32(%ebp) ,ft_tab) // 12 rounds for 128-bit key +3: fwd_rnd1( -32(%ebp) ,ft_tab) // 12 rounds for 192-bit key fwd_rnd2( -16(%ebp) ,ft_tab) 4: fwd_rnd1( (%ebp) ,ft_tab) // 10 rounds for 128-bit key fwd_rnd2( +16(%ebp) ,ft_tab) @@ -334,18 +333,17 @@ aes_dec_blk: xor 8(%ebp),%r4 xor 12(%ebp),%r5 - sub $8,%esp // space for register saves on stack - sub $16,%ebp // increment to next round key - sub $10,%r3 - je 4f // 10 rounds for 128-bit key - sub $32,%ebp - sub $2,%r3 - je 3f // 12 rounds for 128-bit key - sub $32,%ebp + sub $8,%esp // space for register saves on stack + sub $16,%ebp // increment to next round key + cmp $12,%r3 + jb 4f // 10 rounds for 128-bit key + lea -32(%ebp),%ebp + je 3f // 12 rounds for 192-bit key + lea -32(%ebp),%ebp -2: inv_rnd1( +64(%ebp), it_tab) // 14 rounds for 128-bit key +2: inv_rnd1( +64(%ebp), it_tab) // 14 rounds for 256-bit key inv_rnd2( +48(%ebp), it_tab) -3: inv_rnd1( +32(%ebp), it_tab) // 12 rounds for 128-bit key +3: inv_rnd1( +32(%ebp), it_tab) // 12 rounds for 192-bit key inv_rnd2( +16(%ebp), it_tab) 4: inv_rnd1( (%ebp), it_tab) // 10 rounds for 128-bit key inv_rnd2( -16(%ebp), it_tab) |