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Re: Design a microcontroller for gcc
On Wed, 15 Feb 2006, DJ Delorie wrote:
I wrote:
> > Anyway, at least keep a way to add reg+reg and reg+integer, load and
> > store of memory and load of integer and address without condition
> > code effects and your port has a chance to avoid the related bloat.
>
> At least, move/load/store shouldn't touch flags.
I may have listed more operations than necessary, but the
important bit is that you need to form arbitrary addresses in
the stack frame without touching flags. If for any const_int N,
(plus reg N) is a valid address for moves to and from memory
that doesn't touch flags, then I suppose you don't *need* an
"add" that doesn't touch flags.
brgds, H-P