On Oct 26, 2011, at 9:56 AM, Isaac Marino Bavaresco wrote:

> I'm pretty sure that with optimizations on, the compiler
> would remove the redundant instructions.

It would have to be done at link time rather than compile time, =20
because the actual SFR addresses aren't defined until link time.  =20
That's why my original message in this sub-thread was questioning the =20
wisdom of defining SFR addresses at link time.  (the redundant =20
instructions are created with (gcc) compiler optimizations turned on; =20
frankly I don't see how they can be avoided if the SFR addresses =20
aren't known at that point.  It's not even a gcc "failure to =20
optimize"; it's not having the right info (constants) at the right =20
time...)

(Can someone run the code segment through the full optimizing PICC32 =20
compiler and see if it does better?  A code segment like this should =20
be sufficient:
   LATBSET =3D 1;
   LATBCLR =3D 1;
)

BillW

--=20
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