Re: [Gnu-arch-users] Slow inventories on large source trees

[Aaron Bentley]

Tom Lord wrote:

> Abently, are you interested in working on this?  Do you know about the
> `cut' operator in Rx?  (I.e., you don't want to combine those
> filename_matches calls by adding parentheses to regexps.  You want to
> arrange for the final state label of the dfa to tell you which pattern
> matched.)

Okay, I've tried it, and it's a horrible pessimization.  I don't 
understand why.  Output in the WINE tree is identical.  As for function 
calls:

without cuts:
real    0m9.604s
user    0m9.490s
sys     0m0.110s

regexec: 32572
filename_matches: 32572


with cuts:
real    2m43.587s !!!!
user    2m42.470s
sys     0m0.490s

regexec: 18036
filename_matches: 14402
filename_matches_cut: 3634


Perhaps you'd like to have a look?  My reading of the gprof output says 
that filename_matches is still consuming most of the runtime, and that 
can't be right, 'cause I've *removed* calls, not added them.

address@hidden/tlasrc--inventory--0

(note: the code's pretty messy, but there's no point making it pretty if 
 it doesn't work)

Aaron