Add pl.when function

PiperOrigin-RevId: 543791101

jax_triton/pallas/__init__.py

@@ -33,6 +33,7 @@
 from jax_triton.pallas.primitives import program_id
 from jax_triton.pallas.primitives import store
 from jax_triton.pallas.primitives import swap
+from jax_triton.pallas.utils import when
 from jax_triton.utils import cdiv
 
 from jax_triton.pallas import registration

jax_triton/pallas/utils.py

@@ -0,0 +1,26 @@
+# Copyright 2023 The jax_triton Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Pallas utility functions."""
+from jax import lax
+
+
+def when(condition):
+  def _wrapped(f):
+    if isinstance(condition, bool):
+      if condition:
+        f()
+    else:
+      lax.cond(condition, f, lambda: None)
+  return _wrapped