On Oct 26, 2011, at 3:17 AM, Isaac Marino Bavaresco wrote:

> What the OP wants?
> I can see "load the bit mask" -> "load base address" -> "output the
> value at base address+offset".

The original complaint was against the slightly larger piece of
source code for:
   digitalWriteFast(3,1);
   digitalWriteFast(3,0);
Which produced:
   li      v0,1
   lui     v1,0xbf88
   sw      v0,24808(v1)
   lui     v1,0xbf88
   sw      v0,24804(v1)
Which has an obvious extra instruction.
In a loop, two different registers are used to hold the (same)
address "page" of two io registers.

It's similar to setting the RAM page explicitly for every access
on PIC16; not really horrible, but exactly the sort of thing that
I would hope a compiler would NOT do.  I guess Microchip is really
hooked on the idea!  :-)

BillW

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