[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>
diff --git a/arch/i386/crypto/aes-i586-asm.S b/arch/i386/crypto/aes-i586-asm.S
index 7b73c67..911b153 100644
--- a/arch/i386/crypto/aes-i586-asm.S
+++ b/arch/i386/crypto/aes-i586-asm.S
@@ -255,18 +255,17 @@
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
+ 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 128-bit key
+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 @@
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)