rpc: add support for wiring.Component.

Do not infer the ports from the publicly accessible wires, but instead
delegate finding the ports to the `rtlil.convert` function.

amaranth/rpc.py

@@ -3,6 +3,8 @@
 import argparse
 import importlib
 
+from amaranth.lib.wiring import Signature
+
 from .hdl import Signal, Record, Elaboratable
 from .back import rtlil
 
@@ -68,12 +70,14 @@ def _serve_yosys(modules):
 
             try:
                 elaboratable = modules[module_name](*args, **kwargs)
-                ports = []
-                # By convention, any public attribute that is a Signal or a Record is
-                # considered a port.
-                for port_name, port in vars(elaboratable).items():
-                    if not port_name.startswith("_") and isinstance(port, (Signal, Record)):
-                        ports += port._lhs_signals()
+                ports = None
+                if not (hasattr(elaboratable, "signature") and isinstance(elaboratable.signature, Signature)):
+                    ports = []
+                    # By convention, any public attribute that is a Signal or a Record is
+                    # considered a port.
+                    for port_name, port in vars(elaboratable).items():
+                        if not port_name.startswith("_") and isinstance(port, (Signal, Record)):
+                            ports += port._lhs_signals()
                 rtlil_text = rtlil.convert(elaboratable, name=module_name, ports=ports)
                 response = {"frontend": "ilang", "source": rtlil_text}
             except Exception as error:

docs/changes.rst

@@ -9,6 +9,7 @@ Documentation for past releases
 
 Documentation for past releases of the Amaranth language and toolchain is available online:
 
+* `Amaranth 0.5.3 <https://amaranth-lang.org/docs/amaranth/v0.5.3/>`_
 * `Amaranth 0.5.2 <https://amaranth-lang.org/docs/amaranth/v0.5.2/>`_
 * `Amaranth 0.5.1 <https://amaranth-lang.org/docs/amaranth/v0.5.1/>`_
 * `Amaranth 0.5.0 <https://amaranth-lang.org/docs/amaranth/v0.5.0/>`_
@@ -21,8 +22,8 @@ Documentation for past releases of the Amaranth language and toolchain is availa
 * `Amaranth 0.3 <https://amaranth-lang.org/docs/amaranth/v0.3/>`_
 
 
-Version 0.5.3 (unreleased)
-==========================
+Version 0.5.3
+=============
 
 
 Language changes
@@ -31,6 +32,12 @@ Language changes
 * Added: individual bits of the same signal can now be assigned from different modules or domains.
 
 
+Toolchain changes
+-----------------
+
+* Added: the Amaranth RPC server can now elaborate :class:`amaranth.lib.wiring.Component` objects on demand.
+
+
 Version 0.5.2
 =============