| Message ID | 1453902888-20457-2-git-send-email-armbru@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 01/27/2016 06:54 AM, Markus Armbruster wrote: > For a simple union SU, gen_visit_union() generates a visit of its > single tag member, like this: > > visit_type_SUKind(v, "type", &(*obj)->type, &err); > > For a flat union FU with base B, it generates a visit of its base > fields: > > visit_type_B_fields(v, (B **)obj, &err); > > Instead, we can simply visit the common members using the same fields > visit function we use for structs, generated with > gen_visit_struct_fields(). This function visits the base if any, then > the local members. I like how you've split up my gen_struct/gen_union merge into a few more steps. I'll be incorporating your patch into my v10 spin. > > For a simple union SU, visit_type_SU_fields() contains exactly the old > tag member visit, because there is no base, and the tag member is the > only member. For instance, the code generated for > qapi-schema-test.json's UserDefNativeListUnion changes like this: > > @@ -740,6 +766,19 @@ out: > error_propagate(errp, err); > } > > +static void visit_type_UserDefNativeListUnion_fields(Visitor *v, UserDefNativeListUnion **obj, Error **errp) I may try to rewrite the commit to pick a shorter example, though :) > > As you see, the generated code grows a bit, but in practice, it's lost > in the noise: qapi-schema.json's qapi-visit.c gains roughly 1%. > > This simplification became possible with commit 441cbac "qapi-visit: > Convert to QAPISchemaVisitor, fixing bugs". It's a step towards > unifying gen_struct() and gen_union(). > > Signed-off-by: Markus Armbruster <armbru@redhat.com> > --- > scripts/qapi-visit.py | 27 ++++----------------------- > 1 file changed, 4 insertions(+), 23 deletions(-) >
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py index 573bb81..5c0d4d2 100644 --- a/scripts/qapi-visit.py +++ b/scripts/qapi-visit.py @@ -238,11 +238,8 @@ out: return ret -def gen_visit_union(name, base, variants): - ret = '' - - if base: - ret += gen_visit_fields_decl(base) +def gen_visit_union(name, base, members, variants): + ret = gen_visit_struct_fields(name, base, members) for var in variants.variants: # Ugly special case for simple union TODO get rid of it @@ -262,21 +259,9 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error if (!*obj) { goto out_obj; } + visit_type_%(c_name)s_fields(v, obj, &err); ''', c_name=c_name(name)) - - if base: - ret += mcgen(''' - visit_type_%(c_name)s_fields(v, (%(c_name)s **)obj, &err); -''', - c_name=base.c_name()) - else: - ret += mcgen(''' - visit_type_%(c_type)s(v, "%(name)s", &(*obj)->%(c_name)s, &err); -''', - c_type=variants.tag_member.type.c_name(), - c_name=c_name(variants.tag_member.name), - name=variants.tag_member.name) ret += gen_err_check(label='out_obj') ret += mcgen(''' if (!visit_start_union(v, !!(*obj)->u.data, &err) || err) { @@ -381,11 +366,7 @@ class QAPISchemaGenVisitVisitor(QAPISchemaVisitor): def visit_object_type(self, name, info, base, members, variants): self.decl += gen_visit_decl(name) if variants: - if members: - # Members other than variants.tag_member not implemented - assert len(members) == 1 - assert members[0] == variants.tag_member - self.defn += gen_visit_union(name, base, variants) + self.defn += gen_visit_union(name, base, members, variants) else: self.defn += gen_visit_struct(name, base, members)
For a simple union SU, gen_visit_union() generates a visit of its single tag member, like this: visit_type_SUKind(v, "type", &(*obj)->type, &err); For a flat union FU with base B, it generates a visit of its base fields: visit_type_B_fields(v, (B **)obj, &err); Instead, we can simply visit the common members using the same fields visit function we use for structs, generated with gen_visit_struct_fields(). This function visits the base if any, then the local members. For a simple union SU, visit_type_SU_fields() contains exactly the old tag member visit, because there is no base, and the tag member is the only member. For instance, the code generated for qapi-schema-test.json's UserDefNativeListUnion changes like this: @@ -740,6 +766,19 @@ out: error_propagate(errp, err); } +static void visit_type_UserDefNativeListUnion_fields(Visitor *v, UserDefNativeListUnion **obj, Error **errp) +{ + Error *err = NULL; + + visit_type_UserDefNativeListUnionKind(v, "type", &(*obj)->type, &err); + if (err) { + goto out; + } + +out: + error_propagate(errp, err); +} + void visit_type_UserDefNativeListUnion(Visitor *v, const char *name, UserDefNativeListUnion **obj, Error **errp) { Error *err = NULL; @@ -751,7 +790,7 @@ void visit_type_UserDefNativeListUnion(V if (!*obj) { goto out_obj; } - visit_type_UserDefNativeListUnionKind(v, "type", &(*obj)->type, &err); + visit_type_UserDefNativeListUnion_fields(v, obj, &err); if (err) { goto out_obj; } For a flat union FU, visit_type_FU_fields() contains exactly the old base fields visit, because there is a base, but no members. For instance, the code generated for qapi-schema-test.json's UserDefFlatUnion changes like this: @@ -616,6 +616,19 @@ out: static void visit_type_UserDefUnionBase_fields(Visitor *v, UserDefUnionBase **obj, Error **errp); +static void visit_type_UserDefFlatUnion_fields(Visitor *v, UserDefFlatUnion **obj, Error **errp) +{ + Error *err = NULL; + + visit_type_UserDefUnionBase_fields(v, (UserDefUnionBase **)obj, &err); + if (err) { + goto out; + } + +out: + error_propagate(errp, err); +} + static void visit_type_implicit_UserDefA(Visitor *v, UserDefA **obj, Error **errp) { Error *err = NULL; @@ -651,7 +664,7 @@ void visit_type_UserDefFlatUnion(Visitor if (!*obj) { goto out_obj; } - visit_type_UserDefUnionBase_fields(v, (UserDefUnionBase **)obj, &err); + visit_type_UserDefFlatUnion_fields(v, obj, &err); if (err) { goto out_obj; } As you see, the generated code grows a bit, but in practice, it's lost in the noise: qapi-schema.json's qapi-visit.c gains roughly 1%. This simplification became possible with commit 441cbac "qapi-visit: Convert to QAPISchemaVisitor, fixing bugs". It's a step towards unifying gen_struct() and gen_union(). Signed-off-by: Markus Armbruster <armbru@redhat.com> --- scripts/qapi-visit.py | 27 ++++----------------------- 1 file changed, 4 insertions(+), 23 deletions(-)