From a1ede0e256c4e38d274d8e111374c2e84f8c0f7e Mon Sep 17 00:00:00 2001
From: Andrew Grebenisan <agrebenisan@meta.com>
Date: Thu, 9 Oct 2025 14:19:06 -0700
Subject: [PATCH] Pass which replaces torch quantized embedding byte with
 cadence variant (#14906)

Summary:

As titled

Reviewed By: mcremon-meta, zonglinpeng

Differential Revision: D84109801
---
 backends/cadence/aot/replace_ops.py           | 47 +++++++++++++++++++
 .../aot/tests/test_replace_ops_passes.py      | 46 ++++++++++++++++++
 2 files changed, 93 insertions(+)

diff --git a/backends/cadence/aot/replace_ops.py b/backends/cadence/aot/replace_ops.py
index 7025159e443..3cfc059e75b 100644
--- a/backends/cadence/aot/replace_ops.py
+++ b/backends/cadence/aot/replace_ops.py
@@ -2156,6 +2156,52 @@ def call_operator(self, op, args, kwargs, meta):
         )
 
 
+@register_cadence_pass(CadencePassAttribute(opt_level=0))
+class ReplaceTorchQuantizedEmbeddingWithCadenceQuantizedEmbedding(ExportPass):
+    """
+    Replace torch.ops.quantized_decomposed.embedding_byte.dtype with
+    torch.ops.cadence.quantized_embedding_byte
+    """
+
+    def call_operator(
+        self,
+        op: torch._ops.OpOverload,
+        args: Tuple[Argument, ...],
+        kwargs: Dict[str, Argument],
+        meta: NodeMetadata,
+    ) -> ProxyValue:
+        # Check if the op is the quantized_decomposed.embedding_byte.dtype
+        if (
+            op == exir_ops.edge.quantized_decomposed.embedding_byte.default
+            or op == exir_ops.edge.quantized_decomposed.embedding_byte.dtype
+        ):
+            # Replace with cadence.quantized_embedding_byte
+            if len(args) < 6:
+                raise AssertionError(
+                    f"Expected 6 arguments for embedding_byte, got {len(args)}"
+                )
+            embedding = args[0]
+            scales = args[1]
+            weight_zero_points = args[2]
+            indices = args[5]
+            if op == exir_ops.edge.quantized_decomposed.embedding_byte.dtype:
+                dtype = kwargs.get("dtype", None)
+                if dtype is not None and dtype != torch.float32:
+                    raise AssertionError(
+                        f"Unsupported output dtype for embedding_byte: {dtype}"
+                    )
+
+            new_args = (embedding, scales, weight_zero_points, indices, False)
+            new_kwargs = {}
+            return super().call_operator(
+                exir_ops.edge.cadence.quantized_embedding_byte.default,
+                new_args,
+                new_kwargs,
+                meta,
+            )
+        return super().call_operator(op, args, kwargs, meta)
+
+
 class CommonReplacePasses:
     passes = [
         ReplaceSqueezeAndUnsqueezeWithViewPass,
@@ -2168,6 +2214,7 @@ class CommonReplacePasses:
         ReplacePT2QuantWithCadenceQuantPass,
         ReplacePT2DequantWithCadenceDequantPass,
         ReplacePowWithMulPass,
+        ReplaceTorchQuantizedEmbeddingWithCadenceQuantizedEmbedding,
     ]
 
 
diff --git a/backends/cadence/aot/tests/test_replace_ops_passes.py b/backends/cadence/aot/tests/test_replace_ops_passes.py
index c15755f58c5..e2fbd516757 100644
--- a/backends/cadence/aot/tests/test_replace_ops_passes.py
+++ b/backends/cadence/aot/tests/test_replace_ops_passes.py
@@ -45,6 +45,7 @@
     ReplaceSingleElementTensorArgumentsFromFullOpWithScalarPass,
     ReplaceSplitWithSlicePass,
     ReplaceSqueezeAndUnsqueezeWithViewPass,
+    ReplaceTorchQuantizedEmbeddingWithCadenceQuantizedEmbedding,
     ReplaceTransposedConvWithLinearPass,
     ReplaceTrivialConvWithLinear,
     ReplaceWhereWithFullArgsWithWhereScalar,
@@ -2269,3 +2270,48 @@ def test_replace_aten_linalg_svd_with_cadence_linalg_svd(
             count_node(graph_after_passes, exir_ops.edge.cadence.linalg_svd.default),
             1,
         )
+
+    @expand([("dtype",), ("default",)])
+    @torch.no_grad()
+    def test_replace_quantized_embedding(
+        self,
+        name: str,
+    ) -> None:
+        embedding = torch.ones(5, 6, dtype=torch.int8)
+        indices = torch.tensor([0, 2], dtype=torch.int32)
+        scales = torch.ones(5, 2, dtype=torch.float32)
+        zero_points = None
+
+        original_gm = single_op_builder(
+            placeholders=(embedding, scales, indices),
+            op=(
+                exir_ops.edge.quantized_decomposed.embedding_byte.dtype
+                if name == "dtype"
+                else exir_ops.edge.quantized_decomposed.embedding_byte.default
+            ),
+            args=(embedding, scales, zero_points, -128, 127, indices),
+            kwargs={"dtype": torch.float32} if name == "dtype" else {},
+        )
+
+        p = ReplaceTorchQuantizedEmbeddingWithCadenceQuantizedEmbedding()
+        graph_after_passes = cast(PassResult, p(original_gm)).graph_module
+
+        self.assertEqual(
+            count_node(
+                graph_after_passes,
+                (
+                    exir_ops.edge.quantized_decomposed.embedding_byte.dtype
+                    if name == "dtype"
+                    else exir_ops.edge.quantized_decomposed.embedding_byte.default
+                ),
+            ),
+            0,
+        )
+
+        self.assertEqual(
+            count_node(
+                graph_after_passes,
+                exir_ops.edge.cadence.quantized_embedding_byte.default,
+            ),
+            1,
+        )