diff options
Diffstat (limited to 'arch/sh/lib')
| -rw-r--r-- | arch/sh/lib/checksum.S | 67 |
1 files changed, 18 insertions, 49 deletions
diff --git a/arch/sh/lib/checksum.S b/arch/sh/lib/checksum.S index 3e07074e00..06fed5a21e 100644 --- a/arch/sh/lib/checksum.S +++ b/arch/sh/lib/checksum.S @@ -33,7 +33,8 @@ */ /* - * asmlinkage __wsum csum_partial(const void *buf, int len, __wsum sum); + * unsigned int csum_partial(const unsigned char *buf, int len, + * unsigned int sum); */ .text @@ -45,31 +46,11 @@ ENTRY(csum_partial) * Fortunately, it is easy to convert 2-byte alignment to 4-byte * alignment for the unrolled loop. */ + mov r5, r1 mov r4, r0 - tst #3, r0 ! Check alignment. - bt/s 2f ! Jump if alignment is ok. - mov r4, r7 ! Keep a copy to check for alignment + tst #2, r0 ! Check alignment. + bt 2f ! Jump if alignment is ok. ! - tst #1, r0 ! Check alignment. - bt 21f ! Jump if alignment is boundary of 2bytes. - - ! buf is odd - tst r5, r5 - add #-1, r5 - bt 9f - mov.b @r4+, r0 - extu.b r0, r0 - addc r0, r6 ! t=0 from previous tst - mov r6, r0 - shll8 r6 - shlr16 r0 - shlr8 r0 - or r0, r6 - mov r4, r0 - tst #2, r0 - bt 2f -21: - ! buf is 2 byte aligned (len could be 0) add #-2, r5 ! Alignment uses up two bytes. cmp/pz r5 ! bt/s 1f ! Jump if we had at least two bytes. @@ -77,17 +58,16 @@ ENTRY(csum_partial) bra 6f add #2, r5 ! r5 was < 2. Deal with it. 1: + mov r5, r1 ! Save new len for later use. mov.w @r4+, r0 extu.w r0, r0 addc r0, r6 bf 2f add #1, r6 2: - ! buf is 4 byte aligned (len could be 0) - mov r5, r1 mov #-5, r0 - shld r0, r1 - tst r1, r1 + shld r0, r5 + tst r5, r5 bt/s 4f ! if it's =0, go to 4f clrt .align 2 @@ -109,31 +89,30 @@ ENTRY(csum_partial) addc r0, r6 addc r2, r6 movt r0 - dt r1 + dt r5 bf/s 3b cmp/eq #1, r0 - ! here, we know r1==0 - addc r1, r6 ! add carry to r6 + ! here, we know r5==0 + addc r5, r6 ! add carry to r6 4: - mov r5, r0 + mov r1, r0 and #0x1c, r0 tst r0, r0 - bt 6f - ! 4 bytes or more remaining - mov r0, r1 - shlr2 r1 + bt/s 6f + mov r0, r5 + shlr2 r5 mov #0, r2 5: addc r2, r6 mov.l @r4+, r2 movt r0 - dt r1 + dt r5 bf/s 5b cmp/eq #1, r0 addc r2, r6 - addc r1, r6 ! r1==0 here, so it means add carry-bit + addc r5, r6 ! r5==0 here, so it means add carry-bit 6: - ! 3 bytes or less remaining + mov r1, r5 mov #3, r0 and r0, r5 tst r5, r5 @@ -159,16 +138,6 @@ ENTRY(csum_partial) mov #0, r0 addc r0, r6 9: - ! Check if the buffer was misaligned, if so realign sum - mov r7, r0 - tst #1, r0 - bt 10f - mov r6, r0 - shll8 r6 - shlr16 r0 - shlr8 r0 - or r0, r6 -10: rts mov r6, r0 |