[PATCH 0/2] aarch64,falkor: memcpy/memmove performance improvements

Siddhesh Poyarekar siddhesh@sourceware.org
Thu May 3 17:52:00 GMT 2018


Hi,

Here are a couple of patches to improve performance of the falkor memcpy
and memmove implementations based on testing on the latest hardware.
The theme of the optimization is to avoid trying to train the hardware
prefetcher for smaller sizes and in the loop tail since that just
mis-trains the prefetcher.  Instead, use multiple registers to aid
reordering wherever possible.  Testing showed that regressions in these
sizes compared to generic memcpy are resolved with this patch.

Siddhesh

Siddhesh Poyarekar (2):
  aarch64,falkor: Ignore prefetcher hints for memmove tail
  Ignore prefetcher tagging for smaller copies

 sysdeps/aarch64/multiarch/memcpy_falkor.S  | 68 ++++++++++++++++++------------
 sysdeps/aarch64/multiarch/memmove_falkor.S | 48 ++++++++++++---------
 2 files changed, 70 insertions(+), 46 deletions(-)

-- 
2.14.3



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