K 10
svn:author
V 3
mjg
K 8
svn:date
V 27
2017-09-08T20:09:14.710788Z
K 7
svn:log
V 379
Allow __builtin_memset instead of bzero for small buffers of known size

In particular this eliminates function calls and related register save/restore
when only few writes would suffice.

Example speed up can be seen in a fstat microbenchmark on AMD Ryzen cpus, where
the throughput went up by ~4.5%.

Thanks to cem@ for benchmarking and reviewing the patch.

MFC after:	1 week

END