Add fusions for OpenAI CLIP (microsoft#20721)

### Description
This PR adds fusions for [OpenAI's CLIP
model](https://huggingface.co/openai/clip-vit-large-patch14-336). Here
is an example of how to run the ORT transformer optimizer for the linked
CLIP model.

```
$ git clone https://github.com/microsoft/onnxruntime
$ cd onnxruntime/onnxruntime/python/tools/transformers
$ python3 optimizer.py --input /path/to/model.onnx --output /path/to/model_opt.onnx --model_type clip --num_heads 16 --hidden_size 1024 --use_external_data_format --opt_level 0
```

### Motivation and Context
This PR helps optimize multi-modal models that use CLIP for the vision
encoder.

onnxruntime/python/tools/transformers/fusion_attention_clip.py

@@ -97,7 +97,33 @@ def fuse(self, normalize_node, input_name_to_nodes, output_name_to_node):
         else:
             # Deal with the first attention after the embedding layer.
             for i in [0, 1]:
-                node_before_layer_norm = self.model.match_parent(normalize_node, "Add", i)
+                node_before_layer_norm = None
+
+                node_before_layer_norm_1 = self.model.match_parent(normalize_node, "Add", i)
+                node_before_layer_norm_2 = self.model.match_parent(normalize_node, "LayerNormalization", i)
+                if node_before_layer_norm_1 is not None:
+                    #           Add -----------+
+                    #            |             |
+                    #        LayerNorm         |
+                    #            |             |
+                    #        LayerNorm         |
+                    #            |             |
+                    #   Attention subgraph     |
+                    #            |             |
+                    #      SkipLayerNorm ------+
+                    node_before_layer_norm = node_before_layer_norm_1
+                elif node_before_layer_norm_2 is not None:
+                    #           Add
+                    #            |
+                    #        LayerNorm --------+
+                    #            |             |
+                    #        LayerNorm         |
+                    #            |             |
+                    #   Attention subgraph     |
+                    #            |             |
+                    #      SkipLayerNorm ------+
+                    node_before_layer_norm = node_before_layer_norm_2
+
                 if node_before_layer_norm is None:
                     continue
                 child = self.model.find_first_child_by_type(
@@ -130,20 +156,32 @@ def fuse(self, normalize_node, input_name_to_nodes, output_name_to_node):
             return
         (_, _, reshape_v, add_v, matmul_v) = v_nodes
 
+        add_mask = None
         add_mask_indices = []
-        qk_nodes = self.model.match_parent_path(
+        qk_nodes = None
+        qk_nodes_1 = self.model.match_parent_path(
             matmul_qkv,
             ["Softmax", "Reshape", "Add", "Reshape", "MatMul"],
             [0, 0, 0, None, 0],
             return_indice=add_mask_indices,
         )
-        if qk_nodes is None:
+        qk_nodes_2 = self.model.match_parent_path(
+            matmul_qkv,
+            ["Softmax", "MatMul"],
+            [0, 0],
+        )
+        if qk_nodes_1 is not None:
+            qk_nodes = qk_nodes_1
+            assert len(add_mask_indices) == 1
+            causal_mask_input_index = 1 - add_mask_indices[0]
+
+            (_softmax_qk, _, add_mask, _, matmul_qk) = qk_nodes
+        elif qk_nodes_2 is not None:
+            qk_nodes = qk_nodes_2
+            (_softmax_qk, matmul_qk) = qk_nodes
+        else:
             logger.debug("fuse_attention: failed to match qk path")
             return
-        assert len(add_mask_indices) == 1
-        causal_mask_input_index = 1 - add_mask_indices[0]
-
-        (_softmax_qk, _, add_mask, _, matmul_qk) = qk_nodes
 
         q_nodes = self.model.match_parent_path(
             matmul_qk, ["Reshape", "Transpose", "Reshape", "Mul", "Add", "MatMul"], [0, 0, 0, 0, None, None]
@@ -172,23 +210,24 @@ def fuse(self, normalize_node, input_name_to_nodes, output_name_to_node):
 
         attention_last_node = reshape_qkv
 
-        # Here we do not match the whole subgraph since it is very complex. Instead, we just check whether a key path
-        # of computing causal mask.
-        causal_mask_nodes = self.model.match_parent_path(
-            add_mask,
-            ["Concat", "Expand", "Unsqueeze", "Unsqueeze", "Where", "Less"],
-            [causal_mask_input_index, 0, 0, 0, 0, 0],
-        )
-        if causal_mask_nodes is None:
-            # If the model is exported with batch_size == 1, there is no Concat node
+        if add_mask is not None:
+            # Here we do not match the whole subgraph since it is very complex. Instead, we just check whether a key path
+            # of computing causal mask.
             causal_mask_nodes = self.model.match_parent_path(
                 add_mask,
-                ["Expand", "Unsqueeze", "Unsqueeze", "Where", "Less"],
-                [causal_mask_input_index, 0, 0, 0, 0],
+                ["Concat", "Expand", "Unsqueeze", "Unsqueeze", "Where", "Less"],
+                [causal_mask_input_index, 0, 0, 0, 0, 0],
             )
             if causal_mask_nodes is None:
-                logger.debug("fuse_attention: failed to match causal mask subgraph")
-                return
+                # If the model is exported with batch_size == 1, there is no Concat node
+                causal_mask_nodes = self.model.match_parent_path(
+                    add_mask,
+                    ["Expand", "Unsqueeze", "Unsqueeze", "Where", "Less"],
+                    [causal_mask_input_index, 0, 0, 0, 0],
+                )
+                if causal_mask_nodes is None:
+                    logger.debug("fuse_attention: failed to match causal mask subgraph")
+                    return
 
         new_node = self.create_attention_node(
             mask_index=None,
@@ -204,7 +243,7 @@ def fuse(self, normalize_node, input_name_to_nodes, output_name_to_node):
             output=attention_last_node.output[0],
             add_qk_str=None,
             scale=None,
-            causal=True,
+            causal=(add_mask is not None),
         )
         if new_node is None:
             return

onnxruntime/python/tools/transformers/fusion_layernorm.py

@@ -38,6 +38,7 @@ def fuse(self, node, input_name_to_nodes: Dict, output_name_to_node: Dict):
               |                      |
               +----------------------+
         """
+        subgraph_nodes = []
         children = self.model.get_children(node, input_name_to_nodes)
         if len(children) == 0 or len(children) > 2:
             return
@@ -53,20 +54,24 @@ def fuse(self, node, input_name_to_nodes: Dict, output_name_to_node: Dict):
 
         div_node = None
         for child in children:
-            div_node = self.model.find_first_child_by_type(child, "Div", input_name_to_nodes, recursive=False)
-            if div_node is not None:
-                break
+            # Check if Sub --> Div exists
+            div_node_1 = self.model.find_first_child_by_type(child, "Div", input_name_to_nodes, recursive=False)
+
+            # Check if Sub --> Cast --> Div
+            div_node_2 = self.model.match_child_path(child, ["Cast", "Div"], exclude=[])
+
+            if div_node_1 is not None:
+                div_node = div_node_1
+            elif div_node_2 is not None:
+                div_node = div_node_2[-1]
         if div_node is None:
             return
 
         path_id, parent_nodes, _ = self.model.match_parent_paths(
             div_node,
             [
                 (["Sqrt", "Add", "ReduceMean", "Pow", "Sub"], [1, 0, 0, 0, 0]),
-                (
-                    ["Sqrt", "Add", "ReduceMean", "Pow", "Cast", "Sub"],
-                    [1, 0, 0, 0, 0, 0],
-                ),
+                (["Sqrt", "Add", "ReduceMean", "Pow", "Cast", "Sub"], [1, 0, 0, 0, 0, 0]),
             ],
             output_name_to_node,
         )
@@ -87,15 +92,22 @@ def fuse(self, node, input_name_to_nodes: Dict, output_name_to_node: Dict):
         if self.model.find_constant_input(pow_node, 2.0) != 1:
             return
 
-        mul_node = input_name_to_nodes[div_node.output[0]][0]
+        temp_node = input_name_to_nodes[div_node.output[0]][0]
+        if temp_node.op_type == "Cast":
+            # Div --> Cast --> Mul
+            subgraph_nodes.append(temp_node)  # add Cast node to list of subgraph nodes
+            mul_node = input_name_to_nodes[temp_node.output[0]][0]
+        else:
+            # Div --> Mul
+            mul_node = temp_node
         if mul_node.op_type != "Mul":
             return
 
         last_add_node = input_name_to_nodes[mul_node.output[0]][0]
         if last_add_node.op_type != "Add":
             return
 
-        subgraph_nodes = [node]
+        subgraph_nodes.append(node)
         subgraph_nodes.extend(children)
         subgraph_nodes.extend(parent_nodes[:-1])
 
@@ -109,7 +121,8 @@ def fuse(self, node, input_name_to_nodes: Dict, output_name_to_node: Dict):
             logger.debug("It is not safe to fuse LayerNormalization node. Skip")
             return
 
-        weight_input = mul_node.input[1 - self.model.input_index(div_node.output[0], mul_node)]
+        node_before_weight = div_node if temp_node.op_type != "Cast" else temp_node
+        weight_input = mul_node.input[1 - self.model.input_index(node_before_weight.output[0], mul_node)]
         if not self.model.is_constant_with_specified_dimension(weight_input, 1, "layernorm weight"):
             return
 

onnxruntime/python/tools/transformers/fusion_quickgelu.py

@@ -0,0 +1,74 @@
+# -------------------------------------------------------------------------
+# Copyright (c) Microsoft Corporation.  All rights reserved.
+# Licensed under the MIT License.
+# --------------------------------------------------------------------------
+
+import logging
+
+from fusion_base import Fusion
+from onnx import helper
+from onnx_model import OnnxModel
+
+logger = logging.getLogger(__name__)
+
+
+class FusionQuickGelu(Fusion):
+    def __init__(self, model: OnnxModel):
+        super().__init__(model, "QuickGelu", ["Mul"])
+
+    def fuse(self, node, input_name_to_nodes, output_name_to_node):
+        # Fuse the following subgraph to `QuickGelu`
+        #
+        #       root_input
+        #      /          \
+        #     |           Mul       ----+
+        #     |       (B = ~1.702)      |
+        #      \           |            |
+        #       \       Sigmoid         |---- `QuickGelu`
+        #        \     /                |
+        #         \   /                 |
+        #          Mul              ----+
+        #           |
+        #       root_output
+
+        if node.op_type != "Mul":
+            logger.debug("fuse_quickgelu: failed to match second Mul node")
+            return
+
+        second_mul_node = node
+        root_input = second_mul_node.input[0]
+
+        sigmoid_node = self.model.match_parent_path(second_mul_node, ["Sigmoid"], [1])
+        if sigmoid_node is None:
+            logger.debug("fuse_quickgelu: failed to match Sigmoid node")
+            return
+        sigmoid_node = sigmoid_node[0]
+
+        first_mul_node = self.model.match_parent_path(sigmoid_node, ["Mul"], [0])
+        if first_mul_node is None:
+            logger.debug("fuse_quickgelu: failed to match first Mul node")
+            return
+        first_mul_node = first_mul_node[0]
+
+        approximation_value = self.model.get_constant_value(first_mul_node.input[1]).item()
+        if abs(approximation_value - 1.7021484375) >= 1e-3:
+            logger.debug("fuse_quickgelu: failed to match approximation value")
+            return
+
+        if first_mul_node.input[0] != root_input:
+            logger.debug("fuse_quickgelu: failed to match root input with first Mul node's input")
+            return
+
+        new_node = helper.make_node(
+            "QuickGelu",
+            inputs=[root_input],
+            outputs=[second_mul_node.output[0]],
+            name=self.model.create_node_name("QuickGelu"),
+        )
+        new_node.domain = "com.microsoft"
+        new_node.attribute.extend([helper.make_attribute("alpha", approximation_value)])
+
+        self.nodes_to_remove.extend([first_mul_node, sigmoid_node, second_mul_node])
+        self.nodes_to_add.append(new_node)
+        self.node_name_to_graph_name[new_node.name] = self.this_graph_name
+        self.increase_counter("QuickGelu")

onnxruntime/python/tools/transformers/onnx_model_bert.py

@@ -21,6 +21,7 @@
 from fusion_qordered_gelu import FusionQOrderedGelu
 from fusion_qordered_layernorm import FusionQOrderedLayerNormalization
 from fusion_qordered_matmul import FusionQOrderedMatMul
+from fusion_quickgelu import FusionQuickGelu
 from fusion_reshape import FusionReshape
 from fusion_rotary_attention import FusionRotaryEmbeddings
 from fusion_shape import FusionShape
@@ -65,6 +66,8 @@ def fuse_gelu(self):
         fusion.apply()
         fusion = FusionFastGelu(self)
         fusion.apply()
+        fusion = FusionQuickGelu(self)
+        fusion.apply()
         # Only relevant in models with Q-DQ nodes
         fusion = FusionQOrderedGelu(self)
         fusion.apply()

onnxruntime/python/tools/transformers/onnx_model_clip.py

@@ -25,6 +25,7 @@ def get_fused_operator_statistics(self):
         ops = [
             "Attention",
             "LayerNormalization",
+            "QuickGelu",
             "SkipLayerNormalization",
         ]
         for op in ops:

onnxruntime/test/python/transformers/test_gelu_fusions.py

@@ -21,6 +21,11 @@ def forward(self, x):
         return 0.5 * x * (1.0 + torch.tanh(x * 0.7978845608 * (1.0 + 0.044715 * x * x)))
 
 
+class HuggingfaceQuickGelu(torch.nn.Module):
+    def forward(self, x):
+        return x * torch.sigmoid(1.702 * x)
+
+
 class MegatronGelu(torch.nn.Module):
     def forward(self, x):
         # The original implementation using ones_like, which might cause problem for input with dynamic axes in onnx.
@@ -36,6 +41,7 @@ def forward(self, x):
 test_cases = [
     ("huggingface", "Gelu", HuggingfaceGelu),
     ("huggingface", "FastGelu", HuggingfaceFastGelu),
+    ("huggingface", "QuickGelu", HuggingfaceQuickGelu),
     ("megatron", "Gelu", MegatronGelu),
     ("megatron", "FastGelu", MegatronFastGelu),
 ]