Re: [PATCH v2 3/6] fprintf: Print types only once

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Tue, Dec 14, 2021 at 06:23:07PM +0000, Douglas Raillard escreveu:
> On 12/14/21 2:06 PM, Arnaldo Carvalho de Melo wrote:
> > Em Tue, Dec 07, 2021 at 05:31:48PM +0000, Douglas RAILLARD escreveu:
> > > From: Douglas Raillard <douglas.raillard@arm.com>
> > > 
> > > Use (struct tag).visited member to track what type has been printed
> > > already to avoid printing it twice. This allows producing a valid C
> > > header along with --expand_types.
> > 
> > And here you changed the default, i.e. it is useful to have the current
> > --expand_types behaviour of expanding types as it traverse containers,
> > so I think this needs another option to ask for this new
> > behaviour, I think we can have that as --expand_types_once that would be
> > used instead of --expand_types, ok?
> 
> Changed it to have --expand_types_once in the next version I'll send.

Ok, just one other nit, to make the patch smaller, please just use
continue:

diff --git a/pahole.c b/pahole.c
index f3a51cb2fe74afd2..b8beb71ae2c6a0b0 100644
--- a/pahole.c
+++ b/pahole.c
@@ -2964,6 +2964,9 @@ out_btf:
                        goto dump_it;
                }

+               if (class && class->printed)
+                       continue;
+
                if (class)
                        class__find_holes(tag__class(class));
                if (reorganize) {

> > - Arnaldo
> > > Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
> > > ---
> > >   dwarves.h         |  3 ++-
> > >   dwarves_fprintf.c | 22 ++++++++++++++++------
> > >   pahole.c          | 34 ++++++++++++++++++----------------
> > >   3 files changed, 36 insertions(+), 23 deletions(-)
> > > 
> > > diff --git a/dwarves.h b/dwarves.h
> > > index 52d162d..fc5b3fa 100644
> > > --- a/dwarves.h
> > > +++ b/dwarves.h
> > > @@ -413,6 +413,7 @@ struct tag {
> > >   	type_id_t	 type;
> > >   	uint16_t	 tag;
> > >   	bool		 visited;
> > > +	bool		 printed;
> > >   	bool		 top_level;
> > >   	bool		 has_btf_type_tag;
> > >   	uint16_t	 recursivity_level;
> > > @@ -1370,7 +1371,7 @@ static inline const char *enumerator__name(const struct enumerator *enumerator)
> > >   void enumeration__delete(struct type *type);
> > >   void enumeration__add(struct type *type, struct enumerator *enumerator);
> > > -size_t enumeration__fprintf(const struct tag *tag_enum,
> > > +size_t enumeration__fprintf(struct tag *tag_enum,
> > >   			    const struct conf_fprintf *conf, FILE *fp);
> > >   int dwarves__init(void);
> > > diff --git a/dwarves_fprintf.c b/dwarves_fprintf.c
> > > index c5921d7..2c5dce6 100644
> > > --- a/dwarves_fprintf.c
> > > +++ b/dwarves_fprintf.c
> > > @@ -278,8 +278,8 @@ size_t typedef__fprintf(const struct tag *tag, const struct cu *cu,
> > >   {
> > >   	struct type *type = tag__type(tag);
> > >   	const struct conf_fprintf *pconf = conf ?: &conf_fprintf__defaults;
> > > -	const struct tag *tag_type;
> > > -	const struct tag *ptr_type;
> > > +	struct tag *tag_type;
> > > +	struct tag *ptr_type;
> > >   	char bf[512];
> > >   	int is_pointer = 0;
> > >   	size_t printed;
> > > @@ -394,13 +394,14 @@ out:
> > >   	return type->max_tag_name_len;
> > >   }
> > > -size_t enumeration__fprintf(const struct tag *tag, const struct conf_fprintf *conf, FILE *fp)
> > > +size_t enumeration__fprintf(struct tag *tag, const struct conf_fprintf *conf, FILE *fp)
> > >   {
> > >   	struct type *type = tag__type(tag);
> > >   	struct enumerator *pos;
> > >   	int max_entry_name_len = enumeration__max_entry_name_len(type);
> > >   	size_t printed = fprintf(fp, "enum%s%s {\n", type__name(type) ? " " : "", type__name(type) ?: "");
> > >   	int indent = conf->indent;
> > > +	tag->printed = 1;
> > >   	if (indent >= (int)sizeof(tabs))
> > >   		indent = sizeof(tabs) - 1;
> > > @@ -651,10 +652,14 @@ static size_t type__fprintf(struct tag *type, const struct cu *cu,
> > >   	size_t printed = 0;
> > >   	int expand_types = conf->expand_types;
> > >   	int suppress_offset_comment = conf->suppress_offset_comment;
> > > +	bool type_printed;
> > >   	if (type == NULL)
> > >   		goto out_type_not_found;
> > > +	type_printed = type->printed;
> > > +	type->printed = 1;
> > > +
> > >   	if (conf->expand_pointers) {
> > >   		int nr_indirections = 0;
> > > @@ -794,7 +799,7 @@ print_default:
> > >   	case DW_TAG_structure_type:
> > >   		ctype = tag__type(type);
> > > -		if (type__name(ctype) != NULL && !expand_types) {
> > > +		if (type__name(ctype) != NULL && (!expand_types || type_printed)) {
> > >   			printed += fprintf(fp, "%s %-*s %s",
> > >   					   (type->tag == DW_TAG_class_type &&
> > >   					    !tconf.classes_as_structs) ? "class" : "struct",
> > > @@ -813,7 +818,7 @@ print_default:
> > >   	case DW_TAG_union_type:
> > >   		ctype = tag__type(type);
> > > -		if (type__name(ctype) != NULL && !expand_types) {
> > > +		if (type__name(ctype) != NULL && (!expand_types || type_printed)) {
> > >   			printed += fprintf(fp, "union %-*s %s", tconf.type_spacing - 6, type__name(ctype), name ?: "");
> > >   		} else {
> > >   			tconf.type_spacing -= 8;
> > > @@ -823,7 +828,7 @@ print_default:
> > >   	case DW_TAG_enumeration_type:
> > >   		ctype = tag__type(type);
> > > -		if (type__name(ctype) != NULL)
> > > +		if (type__name(ctype) != NULL || type_printed)
> > >   			printed += fprintf(fp, "enum %-*s %s", tconf.type_spacing - 5, type__name(ctype), name ?: "");
> > >   		else
> > >   			printed += enumeration__fprintf(type, &tconf, fp);
> > > @@ -1000,6 +1005,8 @@ static size_t union__fprintf(struct type *type, const struct cu *cu,
> > >   	uint32_t initial_union_cacheline;
> > >   	uint32_t cacheline = 0; /* This will only be used if this is the outermost union */
> > > +	type__tag(type)->printed = 1;
> > > +
> > >   	if (indent >= (int)sizeof(tabs))
> > >   		indent = sizeof(tabs) - 1;
> > > @@ -1394,6 +1401,8 @@ static size_t __class__fprintf(struct class *class, const struct cu *cu,
> > >   				 type__name(type) ?: "");
> > >   	int indent = cconf.indent;
> > > +	class__tag(class)->printed = 1;
> > > +
> > >   	if (indent >= (int)sizeof(tabs))
> > >   		indent = sizeof(tabs) - 1;
> > > @@ -1856,6 +1865,7 @@ size_t tag__fprintf(struct tag *tag, const struct cu *cu,
> > >   	size_t printed = 0;
> > >   	struct conf_fprintf tconf;
> > >   	const struct conf_fprintf *pconf = conf;
> > > +	tag->printed = 1;
> > >   	if (conf == NULL) {
> > >   		tconf = conf_fprintf__defaults;
> > > diff --git a/pahole.c b/pahole.c
> > > index f3a51cb..42ba110 100644
> > > --- a/pahole.c
> > > +++ b/pahole.c
> > > @@ -2964,22 +2964,24 @@ out_btf:
> > >   			goto dump_it;
> > >   		}
> > > -		if (class)
> > > -			class__find_holes(tag__class(class));
> > > -		if (reorganize) {
> > > -			if (class && tag__is_struct(class))
> > > -				do_reorg(class, cu);
> > > -		} else if (find_containers)
> > > -			print_containers(cu, class_id, 0);
> > > -		else if (find_pointers_in_structs)
> > > -			print_structs_with_pointer_to(cu, class_id);
> > > -		else if (class) {
> > > -			/*
> > > -			 * We don't need to print it for every compile unit
> > > -			 * but the previous options need
> > > -			 */
> > > -			tag__fprintf(class, cu, &conf, stdout);
> > > -			putchar('\n');
> > > +		if (!class->printed) {
> > > +			if (class)
> > > +				class__find_holes(tag__class(class));
> > > +			if (reorganize) {
> > > +				if (class && tag__is_struct(class))
> > > +					do_reorg(class, cu);
> > > +			} else if (find_containers)
> > > +				print_containers(cu, class_id, 0);
> > > +			else if (find_pointers_in_structs)
> > > +				print_structs_with_pointer_to(cu, class_id);
> > > +			else if (class) {
> > > +				/*
> > > +				 * We don't need to print it for every compile unit
> > > +				 * but the previous options need
> > > +				 */
> > > +				tag__fprintf(class, cu, &conf, stdout);
> > > +				putchar('\n');
> > > +			}
> > >   		}
> > >   	}
> > > -- 
> > > 2.25.1
> > 

-- 

- Arnaldo