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Re: PATCH: Add objc-lang.c, further cleanup - TAKE TWO



On Monday, December 3, 2001, at 04:04 , Stan Shebs wrote:

> Ziemowit Laski wrote:
> This looks good, please go ahead and commit it.  Might as well
> take the opportunity to put the ^L on a line by itself:
>
> ! ^L/* Compute a hash value for a given method SEL_NAME.  */

Done and done. :)

> Incidentally, I understand the purpose of hash_func is to use
> something more predictable than the raw address of a tree node,
> but this does entail a speed hit.  Did you ever get any numbers
> for the effect on the processing of a large ObjC header, like
> OS X or GNUstep Foundation.h or AppKit.h?

Gotta admit I did not measure the speed hit.  However, we absolutely
need address-independent hash functions throughout the compiler for
the upcoming persistent front-end to run properly.

Also, I suspect (although, again, I did not measure it), that the
bucket distribution achieved by the previous HASHFUNCTION macro
wasn't that great.  The algorithm for the new hash_func is stolen
from cpplib, so it ought to be good. :) :)  At any rate, improvements
to hash_func are welcome (so long as it remains address-independent).

--Zem

--------------------------------------------------------------
Ziemowit Laski                   Apple Computer, Inc.
zlaski@apple.com                 2 Infinite Loop, MS 302-4SN
+1.408.974.6229  Fax .1344       Cupertino, CA  95014-2085


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