CVS commit: basesrc/lib/libc/arch/sh3/string

[ITOH Yasufumi <itohy%netbsd.org@localhost>]

Module Name:    basesrc
Committed By:   itohy
Date:           Wed Aug 28 15:34:37 UTC 2002

Modified Files:
        basesrc/lib/libc/arch/sh3/string: ffs.S
        syssrc/sys/lib/libkern/arch/sh3: ffs.S

Log Message:
Slightly improved version of ffs(3).
Partially from SHIMIZU Ryo <ryo%iij.ad.jp@localhost>.  Thanks.
Some cases are slower, but other most cases are faster.

Here's a benchmark on SH-4 200MHz.

return value    C version       previous vers   this version    speed ratio
of ffs()        (ns/call) *1    (ns/call)       (ns/call) *2    (*1/*2)
------------    ------------    -------------   ------------    -----------
 0                86             86              81             1.06
 1               110             86             106 *(slower)   1.04
 2               132             86             106 *           1.25
 3               165            105             117 *           1.41
 4               201            104             116 *           1.73
 5               237            111             107             2.21
 6               271            111             106             2.56
 7               307            126             116             2.65
 8               342            125             116             2.95
 9               376            122             126 *           2.98
10               410            121             127 *           3.23
11               446            139             136             3.28
12               483            140             134             3.60
13               518            146             125             4.14
14               551            146             126             4.37
15               587            161             135             4.35
16               624            162             136             4.59
17               658            141             139             4.73
18               694            142             140             4.96
19               727            160             148             4.91
20               764            161             150             5.09
21               799            167             141             5.67
22               834            167             142             5.87
23               868            181             152             5.71
24               903            181             153             5.90
25               939            146             140             6.71
26               974            146             141             6.91
27              1009            166             152             6.64
28              1044            165             148             7.05
29              1080            171             141             7.66
30              1115            171             141             7.91
31              1151            185             151             7.62
32              1185            186             151             7.85


To generate a diff of this commit:
cvs rdiff -r1.2 -r1.3 basesrc/lib/libc/arch/sh3/string/ffs.S
cvs rdiff -r1.2 -r1.3 syssrc/sys/lib/libkern/arch/sh3/ffs.S

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.