[JAX] Add Python binding for building a colocated Python program

This change adds a Python binding that makes `ifrt::CustomCallProgram` for a
colocated Python program. This Python binding will be used internally in the
colocated Python API implementation. The API does not yet compile the program
into an executable, which will be added separately.

PiperOrigin-RevId: 700443656

jax/BUILD

@@ -1198,5 +1198,6 @@ pytype_library(
         ":util",
         ":xla_bridge",
         "//jax/_src/lib",
+        "//jax/extend:ifrt_programs",
     ] + py_deps("numpy") + py_deps("cloudpickle"),
 )

jax/experimental/colocated_python/func.py

@@ -28,7 +28,8 @@
 from jax._src.traceback_util import api_boundary
 from jax._src.util import wraps
 from jax.experimental.colocated_python import func_backend
-from jax.experimental.colocated_python.serialization import _deserialize_specs, _make_specs_for_serialized_specs, _serialize_specs
+from jax.experimental.colocated_python.serialization import _deserialize_specs, _make_specs_for_serialized_specs, _serialize, _serialize_specs
+from jax.extend.ifrt_programs import ifrt_programs
 
 ShapeDtypeStructTree = Any  # PyTree[api.ShapeDtypeStruct]
 
@@ -141,8 +142,13 @@ def _compile_to_executable(
     devices: xc.DeviceList,
 ) -> Callable[..., Any]:
   """Compiles a Python function into a runtime executable."""
-  # TODO(hyeontaek): Wrap fun as CustomCallProgram and compile it into an
-  # executable.
+  pickled_function = _serialize(fun)
+  program = ifrt_programs.make_colocated_python_program(
+      name, pickled_function, devices, in_specs_leaves, out_specs_leaves
+  )
+  # TODO(hyeontaek): Compile the program and use the executable.
+  del program
+
   del name
   del in_specs_leaves
   del out_specs_leaves

tests/BUILD

@@ -1387,6 +1387,7 @@ jax_multiplatform_test(
     srcs = ["colocated_python_test.py"],
     deps = [
         "//jax:experimental_colocated_python",
+        "//jax/extend:ifrt_programs",
     ],
 )
 

tests/colocated_python_test.py

@@ -22,6 +22,8 @@
 from jax._src.lib import xla_extension_version  # pylint: disable=g-importing-member
 from jax.experimental import colocated_python
 from jax.experimental.colocated_python import func as colocated_python_func
+from jax.experimental.colocated_python import serialization
+from jax.extend.ifrt_programs import ifrt_programs
 import jax.numpy as jnp
 import numpy as np
 
@@ -77,8 +79,22 @@ class ColocatedPythonTest(jtu.JaxTestCase):
 
   def setUp(self):
     super().setUp()
-    if xla_extension_version < 290:
-      self.skipTest("Requires xla_extension_version >= 290")
+    if xla_extension_version < 298:
+      self.skipTest("Requires xla_extension_version >= 298")
+
+  def testMakeColocatedPythonProgram(self):
+    def add_one(x):
+      return x + 1
+
+    cpu_devices = _colocated_cpu_devices(jax.local_devices())
+    sharding = jax.sharding.SingleDeviceSharding(cpu_devices[0])
+    aval = jax.ShapeDtypeStruct((), jnp.int32, sharding=sharding)
+
+    pickled_function = serialization._serialize(add_one)
+    program = ifrt_programs.make_colocated_python_program(
+        "add_one", pickled_function, [cpu_devices[0]], [aval], [aval]
+    )
+    del program
 
   def testSimpleFunction(self):
     @colocated_python.colocated_python