[Qemu-devel] [PATCH 0/7] Improve buffer_is_zero

[Richard Henderson <rth@twiddle.net>]

Patches 1-3 remove the use of ifunc from the implementation.

Patch 5 adjusts the x86 implementation a bit more to take
advantage of ptest (in sse4.1) and unaligned accesses (in avx1).

Patches 2 and 6 are the result of my conversation with Vijaya
Kumar with respect to ThunderX.

Patch 7 is the result of seeing some really really horrible code
produced for ppc64le (gcc 4.9 and mainline).

This has had limited testing.  What I don't know is the best way
to benchmark this -- the only way I know to trigger this is via
the console, by hand, which doesn't make for reasonable timing.


r~


Richard Henderson (7):
  cutils: Remove SPLAT macro
  cutils: Export only buffer_is_zero
  cutils: Rearrange buffer_is_zero acceleration
  cutils: Add generic prefetch
  cutils: Rewrite x86 buffer zero checking
  cutils: Rewrite aarch64 buffer zero checking
  cutils: Rewrite ppc buffer zero checking

 configure             |  21 +-
 include/qemu/cutils.h |   2 -
 migration/ram.c       |   2 +-
 migration/rdma.c      |   5 +-
 util/cutils.c         | 526 +++++++++++++++++++++++++++++++++-----------------
 5 files changed, 352 insertions(+), 204 deletions(-)

-- 
2.7.4