From 56ded708ec38e4cb75a7c7357480ca34c0dc6875 Mon Sep 17 00:00:00 2001 From: Peter Lieven Date: Tue, 26 Mar 2013 10:58:33 +0100 Subject: buffer_is_zero: use vector optimizations if possible performance gain on SSE2 is approx. 20-25%. altivec is not tested. performance for unsigned long arithmetic is unchanged. Signed-off-by: Peter Lieven Reviewed-by: Eric Blake Reviewed-by: Orit Wasserman Signed-off-by: Juan Quintela --- util/cutils.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'util') diff --git a/util/cutils.c b/util/cutils.c index 0696a3ba5e..5024253405 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -215,6 +215,11 @@ bool buffer_is_zero(const void *buf, size_t len) long d0, d1, d2, d3; const long * const data = buf; + /* use vector optimized zero check if possible */ + if (can_use_buffer_find_nonzero_offset(buf, len)) { + return buffer_find_nonzero_offset(buf, len) == len; + } + assert(len % (4 * sizeof(long)) == 0); len /= sizeof(long); -- cgit v1.2.1