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>
We modify protoc-gen-go to stop generating exported XXX fields.
The unsafe implementation is unaffected by this change since unsafe
can access fields regardless of visibility. However, for the purego
implementation, we need to respect Go visibility rules as enforced
by the reflect package.
We work around this by generating a exporter function that given
a reference to the message and the field to export, returns a reference
to the unexported field value. This exporter function is protected by
a constant such that it is not linked into the final binary in non-purego
build environment.
Updates golang/protobuf#276
Change-Id: Idf5c1f158973fa1c61187ff41440acb21c5dac94
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/185141
Reviewed-by: Damien Neil <dneil@google.com>
The internal/fileinit package is split apart into two packages:
* internal/filedesc constructs descriptors from the raw proto.
It is very similar to the previous internal/fileinit package.
* internal/filetype wraps descriptors with Go type information
Overview:
* The internal/fileinit package will be deleted in a future CL.
It is kept around since the v1 repo currently depends on it.
* The internal/prototype package is deleted. All former usages of it
are now using internal/filedesc instead. Most significantly,
the reflect/protodesc package was almost entirely re-written.
* The internal/impl package drops support for messages that do not
have a Descriptor method (pre-2016). This removes a significant amount
of technical debt.
filedesc.Builder to parse raw descriptors.
* The internal/encoding/defval package now handles enum values by name.
Change-Id: I3957bcc8588a70470fd6c7de1122216b80615ab7
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/182360
Reviewed-by: Damien Neil <dneil@google.com>
Generate the needed infrastructure to ensure that we can statically
enforce minimum and maximum versions. This enables us to have a policy
when we release v2 where it fails to build for:
* new generated code with really old runtimes
* new runtimes with really old generated code
Change-Id: Ib699ad62c06dff8f9285806394a741c18db00288
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/178546
Reviewed-by: Damien Neil <dneil@google.com>
The name MessageType is easily confused with protoreflect.MessageType.
Rename it as MessageInfo, which follows the pattern set by v1,
where the equivalent data structure is called InternalMessageInfo.
Change-Id: I535956e1f7c6e9b07e9585e889d5e93388d0d2ce
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/178478
Reviewed-by: Damien Neil <dneil@google.com>
Rename each generated protobuf package such that the base of the
Go package path is always equal to the Go package name to follow
proper Go package naming conventions.
The Go package name is derived from the .proto source file name by
replacing ".proto" with "pb" and stripping all underscores.
Change-Id: Iea05d1b5d94b1b2821ae10276ab771bb2df93c0e
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/177380
Reviewed-by: Damien Neil <dneil@google.com>