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Re: if-conversion a performance bottleneck


Hi,

On Wed, 3 May 2000, Brad Lucier wrote:
> Your changes to flow.c have cut the number of calls to 
> sbitmap_intersection_of_succs from 40604 to 24225, so they are definitely
> worthwhile.

Yes, that was the purpose of the patch ;)
Anyway, I saw some issues of that patch with one of your other test files,
where the runtime exploded, and on my HDD at home I have another version
which even more reduces the time. If I find time, I'll rewrite the sbitmap
routines for large homogeneous bitmaps, clean up all that stuff and see if
anything comes out of it ;)

Btw. do you have also slightly smaller test cases (a quarter or so)? At
home I only have a slow machine and waiting 10 minutes everytime to see,
if one change was worthwhile is, erhh... slow.

>  rest of compilation   :   1.07 ( 0%) usr   0.00 ( 0%) sys   1.07 ( 0%) wall
>  TOTAL                 : 226.10             1.27           227.32

God! For me that was ca. 1110 seconds ;) (Now I'm down to 580)


Ciao,
Michael.


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