In <[EMAIL PROTECTED]>, on 07/18/2005
at 09:15 AM, Bill Fairchild <[EMAIL PROTECTED]> said:
>OK, I'll byte (pun intended). Why is LH r,=H'5' rather than LA r,5
>atrocious?
Extra cache hits and perhaps extra page hits.
>And why is LH r,FIVE with FIVE DC H'5' worse than atrocious?
What does "worse than atrocious" mean and who[1] said that it was?
The word for code that is worse than some other atrocious code is
still "atrocious".
FIVE DC H'5' is worse because it is a "magic number"; almost
invariably the constant does not really represent 5 but rather some
value[2] that sooner or later will change. When it does, someone will
change the value on the DC and you will wind up with, e.g., FIVE DC
H'7', a source of both confusion and errors.
[1] Well, there was the obnoxious commercial with "whiter than white"
as a precedent.
[2] E.g., entry size, number of rows, duration of sample.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT
ISO position; see <http://patriot.net/~shmuel/resume/brief.html>
We don't care. We don't have to care, we're Congress.
(S877: The Shut up and Eat Your spam act of 2003)
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