Some benchmarks with a very short runtime show significantly
different results across runs on Aarch64 - up to tens of percents.
Increasing the runtime to 100ms+ makes the deviation under 5%.
Tested on Aarch64 and x86-64.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* benchtests/bench-memccpy.c: Replace INNER_LOOP_ITERS
with INNER_LOOP_ITERS_LARGE.
* benchtests/bench-memchr.c: Likewise.
* benchtests/bench-rawmemchr.c: Likewise.
* benchtests/bench-strcat.c: Likewise.
* benchtests/bench-strchr.c: Likewise.
* benchtests/bench-string.h: Likewise.
* benchtests/bench-strlen.c: Likewise.
* benchtests/bench-strncpy.c: Likewise.
* benchtests/bench-strnlen.c: Likewise.
Replace slow byte-oriented tests in several string benchmarks with the
generic implementations from the string/ directory so the comparisons
are more realistic and useful.
* benchtests/bench-stpcpy.c (SIMPLE_STPCPY): Remove function.
(generic_stpcpy): New function.
* benchtests/bench-stpncpy.c (SIMPLE_STPNCPY): Remove function.
(generic_stpncpy): New function.
* benchtests/bench-strcat.c (SIMPLE_STRCAT): Remove function.
(generic_strcat): New function.
* benchtests/bench-strcpy.c (SIMPLE_STRCPY): Remove function.
(generic_strcpy): New function.
* benchtests/bench-strncat.c (SIMPLE_STRNCAT): Remove function.
(STUPID_STRNCAT): Remove function.
(generic_strncat): New function.
* benchtests/bench-strncpy.c (SIMPLE_STRNCPY): Remove function.
(STUPID_STRNCPY): Remove function.
(generic_strncpy): New function.
* benchtests/bench-strnlen.c (SIMPLE_STRNLEN): Remove function.
(generic_strnlen): New function.
(memchr_strnlen): New function.
* benchtests/bench-strlen.c (generic_strlen): Define for WIDE.
(memchr_strlen): Likewise.
Switch the string benchmarks to using bench-timing.h instead
of hp-timing.h directly. This allows the string benchmarks to
be run usefully on architectures such as ARM that do not have
support for hp-timing.h.
In order to do this the tests have been changed from timing each
individual call and picking the lowest execution time recorded to
timing a number of calls and taking the mean execution time.
ChangeLog:
2013-09-04 Will Newton <will.newton@linaro.org>
* benchtests/bench-timing.h (TIMING_PRINT_MEAN): New macro.
* benchtests/bench-string.h: Include bench-timing.h instead
of including hp-timing.h directly. (INNER_LOOP_ITERS): New
define. (HP_TIMING_BEST): Delete macro. (test_init): Remove
call to HP_TIMING_DIFF_INIT.
* benchtests/bench-memccpy.c: Use bench-timing.h macros
instead of hp-timing.h macros.
* benchtests/bench-memchr.c: Likewise.
* benchtests/bench-memcmp.c: Likewise.
* benchtests/bench-memcpy.c: Likewise.
* benchtests/bench-memmem.c: Likewise.
* benchtests/bench-memmove.c: Likewise.
* benchtests/bench-memset.c: Likewise.
* benchtests/bench-rawmemchr.c: Likewise.
* benchtests/bench-strcasecmp.c: Likewise.
* benchtests/bench-strcasestr.c: Likewise.
* benchtests/bench-strcat.c: Likewise.
* benchtests/bench-strchr.c: Likewise.
* benchtests/bench-strcmp.c: Likewise.
* benchtests/bench-strcpy.c: Likewise.
* benchtests/bench-strcpy_chk.c: Likewise.
* benchtests/bench-strlen.c: Likewise.
* benchtests/bench-strncasecmp.c: Likewise.
* benchtests/bench-strncat.c: Likewise.
* benchtests/bench-strncmp.c: Likewise.
* benchtests/bench-strncpy.c: Likewise.
* benchtests/bench-strnlen.c: Likewise.
* benchtests/bench-strpbrk.c: Likewise.
* benchtests/bench-strrchr.c: Likewise.
* benchtests/bench-strspn.c: Likewise.
* benchtests/bench-strstr.c: Likewise.
