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Re: PATCH: powerpc/strchr.S for BPs

Greg McGary <greg@mcgary.org> writes:

> ./words-old 1: 0:09.77 real, 9.75 user, 0.02 sys, 99% CPU
> ./words-old 1: 0:09.85 real, 9.84 user, 0.01 sys, 99% CPU
> ./words-old 1: 0:09.83 real, 9.81 user, 0.02 sys, 100% CPU
> ./words-new 1: 0:10.51 real, 10.50 user, 0.02 sys, 100% CPU
> ./words-new 1: 0:10.50 real, 10.50 user, 0.00 sys, 99% CPU
> ./words-new 1: 0:10.50 real, 10.48 user, 0.02 sys, 99% CPU

This quantifies the overhead:

./words-nul 1: 0:01.85 real, 1.84 user, 0.01 sys, 99% CPU
./words-nul 1: 0:01.85 real, 1.83 user, 0.02 sys, 99% CPU
./words-nul 1: 0:01.85 real, 1.84 user, 0.00 sys, 99% CPU

words-nul links in a dummy strchr that does nothing and returns NULL.
It's output is the same as for the others:

0/45402000 hits for '1'

That puts the slow-down for pure strchr in the return-NULL case at approx 1%.

Greg
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