[fpc-devel] x86_64 Optimizer Overhaul

[Marģers .]

> Nice spot with the "incq" command there.  It
wasn't intentional for that to be split into 3
commands, but is likely just a side-effect of pass
1 not being run twice now... granted, since one of
my criteria was that the code should not be less
optimal, I'll see if I can watch out for that one.

Both versions are kinda equivalent in execution
speed. 

> One interesting thing to note though is that the
read and add work on the 32-bit register, but then
the full 64-bit register is written.

As local variables are meant to be allocated in 
registers, but procedure has calls to other
procedures, they are stored "temporarily" on stack
as 64 bit registers.
It's not an error or at least not an error for
program logic in this case.


> > # [468] inc(sk);
> > --trunk ---------
> > incq 272(%rsp)

> > -- overhaul -------
> > movl 272(%rsp),%eax
> > addl $1,%eax
> > movq %rax,272(%rsp)

> > did you mean to be so?

> > margers