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/power/memset.s | |
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/ape/lib/ap/power/memset.s')
| -rwxr-xr-x | sys/src/ape/lib/ap/power/memset.s | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/sys/src/ape/lib/ap/power/memset.s b/sys/src/ape/lib/ap/power/memset.s new file mode 100755 index 000000000..fa6e8d920 --- /dev/null +++ b/sys/src/ape/lib/ap/power/memset.s @@ -0,0 +1,73 @@ + TEXT memset(SB),$0 +#define BDNZ BC 16,0, + MOVW R3, p+0(FP) /* R3 is pointer */ + +/* + * performance: + * about 100mbytes/sec (8k blocks) on a 603/105 without L2 cache + * drops to 40mbytes/sec (10k blocks) and 28mbytes/sec with 32k blocks + */ + + MOVW n+8(FP), R4 /* R4 is count */ + CMP R4, $0 + BLE ret + MOVW c+4(FP), R5 /* R5 is char */ + +/* + * create 16 copies of c in R5 .. R8 + */ + RLWNM $0, R5, $0xff, R5 + RLWMI $8, R5, $0xff00, R5 + RLWMI $16, R5, $0xffff0000, R5 + MOVW R5, R6 + MOVW R5, R7 + MOVW R5, R8 + +/* + * let STSW do the work for 16 characters or less; aligned and unaligned + */ + CMP R4, $16 + BLE out + +/* + * store enough bytes to align pointer + */ + ANDCC $7,R3, R9 + BEQ l2 + SUBC R9, $8, R9 + MOVW R9, XER + STSW R5, (R3) + ADD R9, R3 + SUB R9, R4 + +/* + * store 16 at a time while there's room + * STSW was used here originally, but it's `completion serialised' + */ +l2: + SRAWCC $4, R4, R9 + BLE out + MOVW R9, CTR +l3: + MOVW R5, 0(R3) + ADD $8, R3, R10 + MOVW R6, 4(R3) + MOVW R7, 0(R10) + ADD $8, R10, R3 + MOVW R8, 4(R10) + BDNZ l3 + RLWNMCC $0, R4, $15, R4 /* residue */ + BEQ ret + +/* + * store up to 16 bytes from R5 .. R8; aligned and unaligned + */ + +out: + MOVW R4, XER + STSW R5, (R3) + +ret: + MOVW 0(FP), R3 + RETURN + END |