Merge branch 'pchandrasekaran/decompose_reverse' into 'main'

Decomposed reverse op into adv_index

See merge request tenstorrent/tvm!49

python/tvm/relay/op/contrib/buda/buda_passes.py

@@ -191,6 +191,37 @@ def callback(self, pre, post, node_map):
             return slice_concatenate
         return post
 
+class DecomposeReverse(DFPatternCallback):
+    def __init__(self):
+        super().__init__(rewrite_once=False, require_type=True)
+        self.input = wildcard()
+        self.pattern = is_op("reverse")(self.input)
+    def callback(self, pre, post, node_map):
+        input_shape = node_map[self.input][0].checked_type.shape
+        axis = int(post.attrs.axis)
+        if int(axis) < 0:
+            axis = abs(int(axis) + int(len(input_shape)))
+        act = post.args[0]
+        start = int(input_shape[axis]) - 1
+        stop = -1
+        step = -1
+        indices = tvm.relay.Constant(tvm.nd.array(np.arange(start,stop,step).astype(int)))
+        if int(axis) == 0:
+            adv_index_out = tvm.relay.adv_index([act,indices])
+            return adv_index_out
+        else:
+            transpose_1_axes = [int(axis)]
+            intermediate = list(set(np.arange(int(len(input_shape))).tolist()).difference(set(transpose_1_axes)))
+            intermediate.sort()
+            transpose_1_axes.extend(intermediate)
+            transpose_2_axes = []
+            transpose_2_axes.extend(np.arange(1,int(len(input_shape))).tolist())
+            transpose_2_axes.insert(int(axis),0)
+            transpose_1 = tvm.relay.transpose(act,axes=transpose_1_axes)
+            adv_index_1 = tvm.relay.adv_index([transpose_1,indices])
+            transpose_2 = tvm.relay.transpose(adv_index_1,axes=transpose_2_axes)
+            return transpose_2
+
 class DecomposeDynamicResize2d(DFPatternCallback):
     def __init__(self):
         super().__init__(require_type=True)
@@ -3710,6 +3741,7 @@ def run_buda_compile_passes(relay_module, params=None, inputs=None, target=None,
     return run_pattern_callbacks(
         relay_module,
         [
+            DecomposeReverse(),
             ConvertLayout(),
             ResolveConvChannels(),
             DecomposeDynamicResize2d(),