On Thu, 26 Jan 2012, Eric Botcazou wrote:
> > Of course get_inner_reference looks through these kind of
> > conversions when returning the ultimate decl in MEM [&foo],
> > see the jumps in tree-ssa-alias.c we perform to re-discover
> > the view-converting cases ... (at some point I realized that
> > this probably wasn't the best design decision). So maybe
> > if the passed type isn't used in any other way we can
> > get around and discover the view-convert and use the alias-type
> > of the MEM_REF ...
>
> But I presume that the regular MEM_REF expander can cope with this case?
Sure.
Btw, we seem to use the TYPE argument solely for the purpose of
the assign_temp call - and in the forwarding to store_field
we pass down the very same alias_set which isn't needed,
we can just use MEM_ALIAS_SET (blk_object) here it seems,
it's different memory after all, no need to conflict with TARGET
(or set MEM_KEEP_ALIAS_SET_P - what's that ..., ah, DECL_NONADDRESSABLE
...).
Of course if you can simplify the code by using the regular
expander all the better (and eliminate the TYPE argument?).
@@ -6299,7 +6302,7 @@ store_field (rtx target, HOST_WIDE_INT b
store_field (blk_object, bitsize, bitpos,
bitregion_start, bitregion_end,
- mode, exp, type, alias_set, nontemporal);
+ mode, exp, type, MEM_ALIAS_SET (blk_object),
nontemporal);
emit_move_insn (target, object);
works for me.
Thanks,
Richard.
