On Thu, Oct 05, 2023 at 02:01:40PM +0000, Tamar Christina wrote:
> gcc/ChangeLog:
>
> * tree-if-conv.cc (INCLUDE_ALGORITHM): Remove.
> (typedef struct ifcvt_arg_entry): New.
> (cmp_arg_entry): New.
> (gen_phi_arg_condition, gen_phi_nest_statement,
> predicate_scalar_phi): Use them.
> - /* Compute phi_arg_map. */
> + /* Compute phi_arg_map, determine the list of unique PHI args and the
> indices
> + where they are in the PHI node. The indices will be used to determine
> + the conditions to apply and their complexity. */
> + auto_vec<tree> unique_args (num_args);
> for (i = 0; i < num_args; i++)
> {
> tree arg;
>
> arg = gimple_phi_arg_def (phi, i);
> if (!phi_arg_map.get (arg))
> - args.quick_push (arg);
> + unique_args.quick_push (arg);
> phi_arg_map.get_or_insert (arg).safe_push (i);
> }
I meant instead of using another vector (unique_args) just do
args.quick_push ({ arg, 0, 0, NULL });
above (to avoid needing another allocation etc.).
> - /* Determine element with max number of occurrences and complexity.
> Looking at only
> - number of occurrences as a measure for complexity isn't enough as all
> usages can
> - be unique but the comparisons to reach the PHI node differ per branch.
> */
> - typedef std::pair <tree, std::pair <unsigned, unsigned>> ArgEntry;
> - auto_vec<ArgEntry> argsKV;
> - for (i = 0; i < args.length (); i++)
> + /* Determine element with max number of occurrences and complexity.
> Looking
> + at only number of occurrences as a measure for complexity isn't enough
> as
> + all usages can be unique but the comparisons to reach the PHI node
> differ
> + per branch. */
> + for (auto arg : unique_args)
And then
for (auto &entry : args)
here with entry.arg instead of arg and
> {
> unsigned int len = 0;
> - for (int index : phi_arg_map.get (args[i]))
> + vec<int> *indices = phi_arg_map.get (arg);
> + for (int index : *indices)
> {
> edge e = gimple_phi_arg_edge (phi, index);
> len += get_bb_num_predicate_stmts (e->src);
> }
>
> - unsigned occur = phi_arg_map.get (args[i])->length ();
> + unsigned occur = indices->length ();
> if (dump_file && (dump_flags & TDF_DETAILS))
> fprintf (dump_file, "Ranking %d as len=%d, idx=%d\n", i, len, occur);
> - argsKV.safe_push ({ args[i], { len, occur }});
> + args.safe_push ({ arg, len, occur, indices });
either
entry.num_compares = len;
entry.occur = occur;
entry.indices = indices;
here or just using entry.{num_occurrences,occur,indices} directly
instead of the extra automatic vars.
> }
>
> + unique_args.release ();
Plus drop this.
Though, if Richi or Jeff think this is ok as is, I won't stand against it.
Jakub
