Hi Paul,
It disables the peephole optimizations in the rx.md file that combine a
load followed by a zero- or sign- extend operation. The disabling
only happens at -O3 (or higher) as although the peepholes reduce the
number of instructions they can introduce pipeline stalls that
actually make the program slower.
Doesn't that mean it should be disabled for any optimization other than
optimize_size?
That is what I thought as well. But Renesas have specifically asked for
this arrangement, so that is what I have done.
Cheers
Nick
