[PATCH v4 3/8] Benchtests: Improve memrchr benchmarks
Noah Goldstein
goldstein.w.n@gmail.com
Tue Jun 7 04:10:14 GMT 2022
On Mon, Jun 6, 2022 at 7:44 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Mon, Jun 6, 2022 at 3:37 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
> >
> > Add a second iteration for memrchr to set `pos` starting from the end
> > of the buffer.
> >
> > Previously `pos` was only set relative to the begining of the
>
> beginning
> > buffer. This isn't really useful for memchr because the beginning
> memrchr
Fixed in V5.
> > of the search space is (buf + len).
> > ---
> > benchtests/bench-memchr.c | 110 ++++++++++++++++++++++----------------
> > 1 file changed, 65 insertions(+), 45 deletions(-)
> >
> > diff --git a/benchtests/bench-memchr.c b/benchtests/bench-memchr.c
> > index 4d7212332f..0facda2fa0 100644
> > --- a/benchtests/bench-memchr.c
> > +++ b/benchtests/bench-memchr.c
> > @@ -76,7 +76,7 @@ do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s, int c,
> >
> > static void
> > do_test (json_ctx_t *json_ctx, size_t align, size_t pos, size_t len,
> > - int seek_char)
> > + int seek_char, int invert_pos)
> > {
> > size_t i;
> >
> > @@ -96,7 +96,10 @@ do_test (json_ctx_t *json_ctx, size_t align, size_t pos, size_t len,
> >
> > if (pos < len)
> > {
> > - buf[align + pos] = seek_char;
> > + if (invert_pos)
> > + buf[align + len - pos] = seek_char;
> > + else
> > + buf[align + pos] = seek_char;
> > buf[align + len] = -seek_char;
> > }
> > else
> > @@ -109,6 +112,7 @@ do_test (json_ctx_t *json_ctx, size_t align, size_t pos, size_t len,
> > json_attr_uint (json_ctx, "pos", pos);
> > json_attr_uint (json_ctx, "len", len);
> > json_attr_uint (json_ctx, "seek_char", seek_char);
> > + json_attr_uint (json_ctx, "invert_pos", invert_pos);
> >
> > json_array_begin (json_ctx, "timings");
> >
> > @@ -123,6 +127,7 @@ int
> > test_main (void)
> > {
> > size_t i;
> > + int repeats;
> > json_ctx_t json_ctx;
> > test_init ();
> >
> > @@ -142,53 +147,68 @@ test_main (void)
> >
> > json_array_begin (&json_ctx, "results");
> >
> > - for (i = 1; i < 8; ++i)
> > + for (repeats = 0; repeats < 2; ++repeats)
> > {
> > - do_test (&json_ctx, 0, 16 << i, 2048, 23);
> > - do_test (&json_ctx, i, 64, 256, 23);
> > - do_test (&json_ctx, 0, 16 << i, 2048, 0);
> > - do_test (&json_ctx, i, 64, 256, 0);
> > -
> > - do_test (&json_ctx, getpagesize () - 15, 64, 256, 0);
> > + for (i = 1; i < 8; ++i)
> > + {
> > + do_test (&json_ctx, 0, 16 << i, 2048, 23, repeats);
> > + do_test (&json_ctx, i, 64, 256, 23, repeats);
> > + do_test (&json_ctx, 0, 16 << i, 2048, 0, repeats);
> > + do_test (&json_ctx, i, 64, 256, 0, repeats);
> > +
> > + do_test (&json_ctx, getpagesize () - 15, 64, 256, 0, repeats);
> > #ifdef USE_AS_MEMRCHR
> > - /* Also test the position close to the beginning for memrchr. */
> > - do_test (&json_ctx, 0, i, 256, 23);
> > - do_test (&json_ctx, 0, i, 256, 0);
> > - do_test (&json_ctx, i, i, 256, 23);
> > - do_test (&json_ctx, i, i, 256, 0);
> > + /* Also test the position close to the beginning for memrchr. */
> > + do_test (&json_ctx, 0, i, 256, 23, repeats);
> > + do_test (&json_ctx, 0, i, 256, 0, repeats);
> > + do_test (&json_ctx, i, i, 256, 23, repeats);
> > + do_test (&json_ctx, i, i, 256, 0, repeats);
> > #endif
> > - }
> > - for (i = 1; i < 8; ++i)
> > - {
> > - do_test (&json_ctx, i, i << 5, 192, 23);
> > - do_test (&json_ctx, i, i << 5, 192, 0);
> > - do_test (&json_ctx, i, i << 5, 256, 23);
> > - do_test (&json_ctx, i, i << 5, 256, 0);
> > - do_test (&json_ctx, i, i << 5, 512, 23);
> > - do_test (&json_ctx, i, i << 5, 512, 0);
> > -
> > - do_test (&json_ctx, getpagesize () - 15, i << 5, 256, 23);
> > - }
> > - for (i = 1; i < 32; ++i)
> > - {
> > - do_test (&json_ctx, 0, i, i + 1, 23);
> > - do_test (&json_ctx, 0, i, i + 1, 0);
> > - do_test (&json_ctx, i, i, i + 1, 23);
> > - do_test (&json_ctx, i, i, i + 1, 0);
> > - do_test (&json_ctx, 0, i, i - 1, 23);
> > - do_test (&json_ctx, 0, i, i - 1, 0);
> > - do_test (&json_ctx, i, i, i - 1, 23);
> > - do_test (&json_ctx, i, i, i - 1, 0);
> > -
> > - do_test (&json_ctx, getpagesize () - 15, i, i - 1, 23);
> > - do_test (&json_ctx, getpagesize () - 15, i, i - 1, 0);
> > -
> > - do_test (&json_ctx, getpagesize () - 15, i, i + 1, 23);
> > - do_test (&json_ctx, getpagesize () - 15, i, i + 1, 0);
> > + }
> > + for (i = 1; i < 8; ++i)
> > + {
> > + do_test (&json_ctx, i, i << 5, 192, 23, repeats);
> > + do_test (&json_ctx, i, i << 5, 192, 0, repeats);
> > + do_test (&json_ctx, i, i << 5, 256, 23, repeats);
> > + do_test (&json_ctx, i, i << 5, 256, 0, repeats);
> > + do_test (&json_ctx, i, i << 5, 512, 23, repeats);
> > + do_test (&json_ctx, i, i << 5, 512, 0, repeats);
> > +
> > + do_test (&json_ctx, getpagesize () - 15, i << 5, 256, 23, repeats);
> > + }
> > + for (i = 1; i < 32; ++i)
> > + {
> > + do_test (&json_ctx, 0, i, i + 1, 23, repeats);
> > + do_test (&json_ctx, 0, i, i + 1, 0, repeats);
> > + do_test (&json_ctx, i, i, i + 1, 23, repeats);
> > + do_test (&json_ctx, i, i, i + 1, 0, repeats);
> > + do_test (&json_ctx, 0, i, i - 1, 23, repeats);
> > + do_test (&json_ctx, 0, i, i - 1, 0, repeats);
> > + do_test (&json_ctx, i, i, i - 1, 23, repeats);
> > + do_test (&json_ctx, i, i, i - 1, 0, repeats);
> > +
> > + do_test (&json_ctx, getpagesize () / 2, i, i + 1, 23, repeats);
> > + do_test (&json_ctx, getpagesize () / 2, i, i + 1, 0, repeats);
> > + do_test (&json_ctx, getpagesize () / 2 + i, i, i + 1, 23, repeats);
> > + do_test (&json_ctx, getpagesize () / 2 + i, i, i + 1, 0, repeats);
> > + do_test (&json_ctx, getpagesize () / 2, i, i - 1, 23, repeats);
> > + do_test (&json_ctx, getpagesize () / 2, i, i - 1, 0, repeats);
> > + do_test (&json_ctx, getpagesize () / 2 + i, i, i - 1, 23, repeats);
> > + do_test (&json_ctx, getpagesize () / 2 + i, i, i - 1, 0, repeats);
> > +
> > + do_test (&json_ctx, getpagesize () - 15, i, i - 1, 23, repeats);
> > + do_test (&json_ctx, getpagesize () - 15, i, i - 1, 0, repeats);
> > +
> > + do_test (&json_ctx, getpagesize () - 15, i, i + 1, 23, repeats);
> > + do_test (&json_ctx, getpagesize () - 15, i, i + 1, 0, repeats);
> > +
> > #ifdef USE_AS_MEMRCHR
> > - /* Also test the position close to the beginning for memrchr. */
> > - do_test (&json_ctx, 0, 1, i + 1, 23);
> > - do_test (&json_ctx, 0, 2, i + 1, 0);
> > + do_test (&json_ctx, 0, 1, i + 1, 23, repeats);
> > + do_test (&json_ctx, 0, 2, i + 1, 0, repeats);
> > +#endif
> > + }
> > +#ifndef USE_AS_MEMRCHR
> > + break;
> > #endif
> > }
> >
> > --
> > 2.34.1
> >
>
>
> --
> H.J.
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