github/esphome
2
0
Fork 0
mirror of https://github.com/esphome/esphome.git synced 2026-09-27 06:50:22 +00:00
Code Issues Packages Projects Releases Wiki Activity

[api] Decode without a vtable

Browse Source 
decode_field() becomes a static per message function and the generated decode() hands it
to the shared loop as a function pointer, so decodable messages carry no vtable and no
vptr store at every construction site. The loop loses the two vtable loads per field. The
protected destructor on ProtoDecodableMessage goes with the virtuals; ProtoMessage keeps
its own guard for the dump builds that still have them.
This commit is contained in:
J. Nick Koston
2026-09-08 04:43:02 +02:00
parent 5ac2fa8811
commit 0e3554f6f8
6 changed files with 675 additions and 412 deletions
Download Patch File Download Diff File Expand all files Collapse all files
script/api_protobuf/api_protobuf.py
+12 -5
View File
@@ -2661,15 +2661,22 @@ def build_message_type(
cpp = ""
if decode:
o = f"void {desc.name}::decode_field(uint32_t tag, const uint8_t *data, proto_varint_value_t scalar) {{\n"
o = f"void {desc.name}::decode_field(void *self, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar) {{\n"
o += f" auto &msg = *static_cast<{desc.name} *>(self);\n"
o += " const ProtoFieldValue value(data, scalar);\n"
o += " switch (tag) {\n"
o += indent("\n".join(decode), " ") + "\n"
o += indent("\n".join(decode), " ").replace("this->", "msg.") + "\n"
o += " }\n"
o += "}\n"
cpp += o
prot = "void decode_field(uint32_t tag, const uint8_t *data, proto_varint_value_t scalar) override;"
prot = "static void decode_field(void *self, uint32_t tag, const uint8_t *data, proto_varint_value_t scalar);"
protected_content.insert(0, prot)
if not fixed_vector_fields:
public_content.append(
"void decode(const uint8_t *buffer, size_t length) {\n"
" ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);\n"
"}"
)
# Generate custom decode() override for messages with FixedVector fields
if fixed_vector_fields:
@@ -2679,8 +2686,8 @@ def build_message_type(
for field_name, field_number in fixed_vector_fields:
o += f" uint32_t count_{field_name} = ProtoDecodableMessage::count_repeated_field(buffer, length, {field_number});\n"
o += f" this->{field_name}.init(count_{field_name});\n"
# Call parent decode to populate the fields
o += " ProtoDecodableMessage::decode(buffer, length);\n"
# Then the shared loop fills them
o += " ProtoDecodableMessage::decode_fields(this, buffer, length, &decode_field);\n"
o += "}\n"
cpp += o
# Generate the decode() declaration in header (public method)