Add a no-op batching rule for optimization_barrier_p

PiperOrigin-RevId: 704507586

jax/_src/lax/lax.py

@@ -6496,3 +6496,7 @@ def _optimization_barrier_lowering_rule(ctx, *args):
 optimization_barrier_p.def_abstract_eval(_optimization_barrier_abstract_eval)
 mlir.register_lowering(optimization_barrier_p,
                        _optimization_barrier_lowering_rule)
+
+def _optimization_barrier_batcher(batched_args, batch_dims, **params):
+  return optimization_barrier_p.bind(*batched_args, **params), batch_dims
+batching.primitive_batchers[optimization_barrier_p] = _optimization_barrier_batcher

tests/lax_test.py

@@ -3551,7 +3551,7 @@ def testAsarray(self, typ):
     with jax.transfer_guard('disallow'):
       jax.jit(asarray_closure)()
 
-  def testOptimizationBarrier(self):
+  def test_optimization_barrier(self):
     x = lax.optimization_barrier((2, 3))
     self.assertEqual((2, 3), x)
 

tests/lax_vmap_test.py

@@ -691,6 +691,25 @@ def testTopK(self, shape, dtype, k, bdims):
     op2 = lambda x: lax.top_k(x, k=k)[1]
     self._CheckBatching(op2, 5, bdims, (shape,), (dtype,), rng)
 
+  @jtu.sample_product(
+    [dict(shape=shape, bdims=bdims)
+      for shape in [(8,), (3, 4, 5)]
+      for bdims in lax_test_util.all_bdims(shape)],
+    dtype=lax_test_util.default_dtypes,
+  )
+  def test_optimization_barrier_vmap(self, shape, dtype, bdims):
+    rng = jtu.rand_small(self.rng())
+    self._CheckBatching(lax.optimization_barrier, 5, bdims, (shape,), (dtype,),
+                        rng)
+
+  def test_optimization_barrier_vmap_out_axes(self):
+    x = jnp.arange(8)
+    y = x.reshape(1, 8)
+    out = jax.vmap(lax.optimization_barrier, in_axes=((0, 1),),
+                   out_axes=(0, 1))((x, y))
+    self.assertArraysEqual(out[0], x)
+    self.assertArraysEqual(out[1], y)
+
   @jtu.sample_product(
     [dict(shape=shape, bdims=bdims, dimension=dimension, arity=arity)
       for shape in [(2, 3)]