I've been busy changing/implementing (new) passes in ocamlopt back-end
for my own target. A collateral of that is that it improves the
generated code for x86 -- ocamlopt is great but isn't exactly an
optimizing compiler :) Simple constant propagation and invariant code
motion sometimes doesn't happen. Below is trivial example -- the if i/
9 >s 201 test may be removed at some stage. I've seen lots of things
like it. This generates inefficient code (on x86 and ARM at least).
I've had up to 30% speed improvement. Of course, the speed can also be
improved by modifying the Ocaml code itself, so I'm not claiming what
I've done is a major improvement at all.
camlA__matchdtree_63(R/0[%eax])
{ + R/0[%eax]}
a/8 := R/0[%eax]
{a/8*}
i/9 := 1
{a/8* i/9}
catch
{a/8* i/9 + i/9}
if i/9 >s 201 then
[...]
Short questions --
(1) Any optimizing option I would be unaware of? Inlining option
doesn't help much.
(2) Any way to contribute this work back to Ocaml community (on a
separate cvs branch?) or is this kind of work planned by the core
Ocaml team?