5 Jul
2021
5 Jul
'21
8:43 p.m.
On Mon, Jul 05, 2021 at 02:23:36PM +1000, George Michaelson wrote:
Forgive me a side note, but has it not been shown for
some time that
apart from a very gifted few people, hand-crafted machine-code is
usually slower than the best optimising compilers these days? With out
of order instruction stuff, side effects (inter-core locking) cache
coherency &c it isn't hard to wind up using "simpler" machine code
which performs worserer.
I dunno where my team sat on the "gifted" scale, I like to think they
were pretty good. We ran our code through Intel's fancy C compiler and
it made less than a 1% difference vs GCC. We cared about performance
and had already done the by hand work to make the critical paths go fast.