On 11/18/23 03:27, Jakub Jelinek wrote:
Hi!
On Fri, Nov 17, 2023 at 03:01:04PM +0100, Jakub Jelinek wrote:
As a follow-up, I'm considering changing in this routine the popcount
call to IFN_POPCOUNT with 2 arguments and during expansion test costs.
Here is the follow-up which does the rtx costs testing.
While having to tweak internal-fn.def so that POPCOUNT can have a custom
expand_POPCOUNT, I have noticed we are inconsistent, some DEF_INTERNAL*
macros (most of them) were undefined at the end of internal-fn.def (but in
some cases uselessly undefined again after inclusion), while others were not
(and sometimes undefined after the inclusion). I've changed it to always
undefine at the end of internal-fn.def.
Ok for trunk if it passes bootstrap/regtest?
2023-11-18 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/90693
* tree-ssa-math-opts.cc (match_single_bit_test): Mark POPCOUNT with
result only used in equality comparison against 1 with direct optab
support as .POPCOUNT call with 2 arguments.
* internal-fn.h (expand_POPCOUNT): Declare.
* internal-fn.def: Document missing DEF_INTERNAL* macros and make sure
they are all undefined at the end.
(DEF_INTERNAL_INT_EXT_FN): New macro.
(POPCOUNT): Use it instead of DEF_INTERNAL_INT_FN.
* internal-fn.cc (lookup_hilo_internal_fn, lookup_evenodd_internal_fn,
widening_fn_p, get_len_internal_fn): Don't undef DEF_INTERNAL_*FN
macros after inclusion of internal-fn.def.
(DEF_INTERNAL_INT_EXT_FN): Define to nothing before inclusion to
define expanders.
(expand_POPCOUNT): New function.
+ unsigned cmp_cost = seq_cost (cmp_insns, speed_p);
+ if (popcount_cost < cmp_cost)
+ emit_insn (popcount_insns);
+ else
+ {
+ emit_insn (cmp_insns);
+ plhs = expand_normal (lhs);
+ if (GET_MODE (cmp) != GET_MODE (plhs))
+ cmp = convert_to_mode (GET_MODE (plhs), cmp, 1);
+ emit_move_insn (plhs, cmp);
+ }
Did you want <= for the test to use popcount? That seems like a better
choice in that scenario to me as the popcount is likely smaller.
OK for the trunk as-is or using a <= test.
jeff
