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Re: Add conditional addition patterns
> On Thu, Nov 21, 2002 at 11:39:58PM +0100, Jan Hubicka wrote:
> > We define inccc/deccc patterns but have no way to generate them.
>
> We do? Where?
Kind of:
Some machines can also perform @code{and} or @code{plus} operations on
condition code values with less instructions than the corresponding
@samp{s@var{cond}} insn followed by @code{and} or @code{plus}. On those
machines, define the appropriate patterns. Use the names @code{incscc}
and @code{decscc}, respectively, for the patterns which perform
@code{plus} or @code{minus} operations on condition code values. See
@file{rs6000.md} for some examples. The GNU Superoptizer can be used to
find such instruction sequences on other machines.
We also ask for existence of these patterns
static int
noce_try_store_flag_inc (if_info)
struct noce_if_info *if_info;
{
rtx target, seq;
int subtract, normalize;
if (! no_new_pseudos
&& (BRANCH_COST >= 2
|| HAVE_incscc
|| HAVE_decscc)
But my patch attempts to solve the situation differently...
Honza
>
>
> r~