Adding support for keyword arguments to staged methods.

PiperOrigin-RevId: 702342993

Author: james-martens

kfac_jax/_src/utils/staging.py

@@ -14,6 +14,7 @@
 """K-FAC utilities for classes with staged methods."""
 
 import functools
+import inspect
 import numbers
 import operator
 from typing import Any, Callable, Sequence
@@ -165,8 +166,15 @@ def staged(
   This decorator **should** only be applied to instance methods of classes that
   inherit from the `WithStagedMethods` class. The decorator makes the decorated
   method staged, which is equivalent to `jax.jit` if `instance.multi_device` is
-  `False` and to `jax.pmap` otherwise. When specifying static and donated
-  argunms, the `self` reference **must not** be counted. Example:
+  `False` and to `jax.pmap` otherwise.
+
+  Note that the point of this abstraction around JAX's compilation is to make
+  sure that jitting/pmapping is only done once, so that if we are already in a
+  compiled/staged method, we won't initiate a second nested compilation when
+  calling into second staged method.
+
+  Note that when specifying static and donated argunms, the `self` reference
+  **must not** be counted. Example:
 
     @functools.partial(staged, donate_argunms=0)
     def try(self, x):
@@ -210,12 +218,22 @@ def try(self, x):
                         donate_argnums=donate_argnums)
 
   @functools.wraps(method)
-  def decorated(instance: "WithStagedMethods", *args: Any) -> TArrayTree:
+  def decorated(
+      instance: "WithStagedMethods",
+      *args: Any,
+      **kwargs: Any
+  ) -> TArrayTree:
+
+    sig = inspect.signature(method)
+    bound_args = sig.bind(instance, *args, **kwargs)
+    bound_args.apply_defaults()
+    args, kwargs = bound_args.args[1:], bound_args.kwargs
 
     if instance.in_staging:
-      return method(instance, *args)
+      return method(instance, *args, **kwargs)
 
     with instance.staging_context():
+
       if instance.multi_device and instance.debug:
         # In this case we want to call `method` once for each device index.
         # Note that this might not always produce sensible behavior, and will
@@ -241,14 +259,16 @@ def decorated(instance: "WithStagedMethods", *args: Any) -> TArrayTree:
               for j in range(len(args))
           ]
 
+          kwargs_i = jax.tree_util.tree_map(operator.itemgetter(i), kwargs)
+
           with jax.disable_jit():
-            outs.append(method(instance, *args_i))
+            outs.append(method(instance, *args_i, **kwargs_i))
 
         outs = jax.tree_util.tree_map(lambda *args_: jnp.stack(args_), *outs)
 
       elif instance.debug:
         with jax.disable_jit():
-          outs = method(instance, *args)
+          outs = method(instance, *args, **kwargs)
 
       elif instance.multi_device:
 
@@ -274,10 +294,10 @@ def decorated(instance: "WithStagedMethods", *args: Any) -> TArrayTree:
           )
           pmap_funcs[key] = func
 
-        outs = func(instance, *args)
+        outs = func(instance, *args, **kwargs)
 
       else:
-        outs = jitted_func(instance, *args)
+        outs = jitted_func(instance, *args, **kwargs)
 
     return outs