diff options
| author | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
|---|---|---|
| committer | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
| commit | e5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch) | |
| tree | d8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/ape/lib/ap/sparc/memset.s | |
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/ape/lib/ap/sparc/memset.s')
| -rwxr-xr-x | sys/src/ape/lib/ap/sparc/memset.s | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/sys/src/ape/lib/ap/sparc/memset.s b/sys/src/ape/lib/ap/sparc/memset.s new file mode 100755 index 000000000..8c7b26c86 --- /dev/null +++ b/sys/src/ape/lib/ap/sparc/memset.s @@ -0,0 +1,88 @@ + TEXT memset(SB),$0 + +/* + * performance: + * (tba) + */ + +MOVW R7, 0(FP) + MOVW n+8(FP), R9 /* R9 is count */ + MOVW p+0(FP), R10 /* R10 is pointer */ + MOVW c+4(FP), R11 /* R11 is char */ + ADD R9,R10, R12 /* R12 is end pointer */ + +/* + * if not at least 4 chars, + * dont even mess around. + * 3 chars to guarantee any + * rounding up to a word + * boundary and 4 characters + * to get at least maybe one + * full word store. + */ + SUBCC $4,R9, R0 + BL out + +/* + * turn R11 into a word of characters + */ + AND $0xff, R11 + SLL $8,R11, R7 + OR R7, R11 + SLL $16,R11, R7 + OR R7, R11 + +/* + * store one byte at a time until pointer + * is alligned on a word boundary + */ +l1: + ANDCC $3,R10, R0 + BE l2 + MOVB R11, 0(R10) + ADD $1, R10 + JMP l1 + +/* + * turn R9 into end pointer-15 + * store 16 at a time while theres room + */ +l2: + ADD $-15,R12, R9 + SUBCC R10,R9, R0 + BLEU l4 +l3: + MOVW R11, 0(R10) + MOVW R11, 4(R10) + ADD $16, R10 + SUBCC R10,R9, R0 + MOVW R11, -8(R10) + MOVW R11, -4(R10) + BGU l3 + +/* + * turn R9 into end pointer-3 + * store 4 at a time while theres room + */ +l4: + ADD $-3,R12, R9 +l5: + SUBCC R10,R9, R0 + BLEU out + MOVW R11, 0(R10) + ADD $4, R10 + JMP l5 + +/* + * last loop, store byte at a time + */ +out: + SUBCC R10,R12, R0 + BLEU ret + MOVB R11, 0(R10) + ADD $1, R10 + JMP out + +ret: + MOVW s1+0(FP), R7 + RETURN |