internal/impl: add MessageState to every generated message
We define MessageState, which is essentially an atomically set *MessageInfo.
By nesting this as the first field in every generated message, we can
implement the reflective methods on a *MessageState when obtained by
unsafe casting a concrete message pointer as a *MessageState.
The MessageInfo held by MessageState provides additional Go type information
to interpret the memory that comes after the contents of the MessageState.
Since we are nesting a MessageState in every message,
the memory use of every message instance grows by 8B.
On average, the body of ProtoReflect grows from 133B to 202B (+50%).
However, this is offset by XXX_Methods, which is 108B and
will be removed in a future CL. Taking into account the eventual removal
of XXX_Methods, this is a net reduction of 25%.
name old time/op new time/op delta
Name/Value-4 70.3ns ± 2% 17.5ns ± 6% -75.08% (p=0.000 n=10+10)
Name/Nil-4 70.6ns ± 3% 33.4ns ± 2% -52.66% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
Name/Value-4 16.0B ± 0% 0.0B -100.00% (p=0.000 n=10+10)
Name/Nil-4 16.0B ± 0% 0.0B -100.00% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
Name/Value-4 1.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10)
Name/Nil-4 1.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10)
Change-Id: I92bd58dc681c57c92612fd5ba7fc066aea34e95a
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/185460
Reviewed-by: Damien Neil <dneil@google.com>
diff --git a/internal/testprotos/test/test_public.pb.go b/internal/testprotos/test/test_public.pb.go
index 01037d5..edef5f9 100644
--- a/internal/testprotos/test/test_public.pb.go
+++ b/internal/testprotos/test/test_public.pb.go
@@ -18,6 +18,7 @@
)
type PublicImportMessage struct {
+ state protoimpl.MessageState
sizeCache protoimpl.SizeCache
unknownFields protoimpl.UnknownFields
}
@@ -33,10 +34,18 @@
func (*PublicImportMessage) ProtoMessage() {}
func (x *PublicImportMessage) ProtoReflect() protoreflect.Message {
- return file_test_test_public_proto_msgTypes[0].MessageOf(x)
+ mi := &file_test_test_public_proto_msgTypes[0]
+ if protoimpl.UnsafeEnabled && x != nil {
+ ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+ if ms.LoadMessageInfo() == nil {
+ ms.StoreMessageInfo(mi)
+ }
+ return ms
+ }
+ return mi.MessageOf(x)
}
-func (m *PublicImportMessage) XXX_Methods() *protoiface.Methods {
+func (x *PublicImportMessage) XXX_Methods() *protoiface.Methods {
return file_test_test_public_proto_msgTypes[0].Methods()
}
@@ -91,8 +100,10 @@
file_test_test_public_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
switch v := v.(*PublicImportMessage); i {
case 0:
- return &v.sizeCache
+ return &v.state
case 1:
+ return &v.sizeCache
+ case 2:
return &v.unknownFields
default:
return nil