Re: [PATCH dwarves v2 02/10] btf_encoder: separate elf function, saved function representations

[Jiri Olsa <olsajiri@gmail.com>]

On Fri, Dec 13, 2024 at 10:36:53PM +0000, Ihor Solodrai wrote:

SNIP

> +	btf_encoders__for_each_encoder(e) {
> +		list_for_each_entry(s, &e->func_states, node)
> +			nr_saved_fns++;
> +	}
> +
> +	if (nr_saved_fns == 0)
> +		return 0;
> +
> +	saved_fns = calloc(nr_saved_fns, sizeof(*saved_fns));
> +	btf_encoders__for_each_encoder(e) {
> +		list_for_each_entry(s, &e->func_states, node)
> +			saved_fns[i++] = s;
> +	}
> +	qsort(saved_fns, nr_saved_fns, sizeof(*saved_fns), saved_functions_cmp);
> +
> +	for (i = 0; i < nr_saved_fns; i = j) {
> +		struct btf_encoder_func_state *state = saved_fns[i];
> +
> +		/* Compare across sorted functions that match by name/prefix;
> +		 * share inconsistent/unexpected reg state between them.
> +		 */
> +		j = i + 1;
> +
> +		while (j < nr_saved_fns && saved_functions_combine(saved_fns[i], saved_fns[j]) == 0)
> +			j++;
> +
> +		/* do not exclude functions with optimized-out parameters; they
> +		 * may still be _called_ with the right parameter values, they
> +		 * just do not _use_ them.  Only exclude functions with
> +		 * unexpected register use or multiple inconsistent prototypes.
> +		 */
> +		if (!encoder->skip_encoding_inconsistent_proto ||
> +		    (!state->unexpected_reg && !state->inconsistent_proto)) {
> +			if (btf_encoder__add_func(state->encoder, state)) {
> +				free(saved_fns);
> +				return -1;
> +			}
> +		}
> +	}
> +	/* Now that we are done with function states, free them. */
> +	free(saved_fns);
> +	btf_encoders__for_each_encoder(e)
> +		btf_encoder__delete_saved_funcs(e);

nit, wrong indent

jirka

> +	return 0;
> +}
> +
>  static int btf_encoder__collect_function(struct btf_encoder *encoder, GElf_Sym *sym)

SNIP