Fix: list index out of range with softmax when using 0 dim

test/inductor/test_cpu_repro.py

@@ -3274,6 +3274,15 @@ class CPUReproTests(TestCase):
         metrics.reset()
         self.common(fn, (x,))
 
+    def test_softmax_with_zero_dim(self):
+        def fn(x):
+            x = torch.softmax(x, 0)
+            return x
+
+        x = torch.rand([], dtype=torch.bfloat16)
+        metrics.reset()
+        self.common(fn, (x,))
+
     @config.patch({"fx_graph_cache": False, "fx_graph_remote_cache": False})
     def test_local_buffer_in_outer_loop_fusion(self):
         def fn(x):

torch/_inductor/fx_passes/joint_graph.py

@@ -892,6 +892,9 @@ def _other_is_broadcasted_in_dim(match):
     if isinstance(dim, int):
         dim = (dim,)
 
+    if any(d >= len(other_shape) for d in dim):
+        return False
+
     return all(statically_known_true(other_shape[d] == 1) for d in dim)