[ExecuTorch][Weight Sharing][XNNPACK] Serialize constant tensors into named data map

backends/xnnpack/_passes/TARGETS

@@ -19,5 +19,6 @@ python_library(
         "//executorch/exir/passes:const_prop_pass",
         "//executorch/exir/passes:memory_format_ops_pass",
         "//executorch/exir/program:program",
+        "//executorch/backends/transforms:utils",
     ],
 )

backends/xnnpack/_passes/fuse_batch_norm_with_conv.py

@@ -7,13 +7,22 @@
 import operator
 
 import torch
+from executorch.backends.transforms.utils import (
+    create_constant_placeholder,
+    delete_constant_placeholder,
+)
 
 from executorch.backends.xnnpack._passes.xnnpack_pass import XNNPACKPass
 
-from executorch.backends.xnnpack.utils.utils import get_param_tensor, is_param_node
+from executorch.backends.xnnpack.utils.utils import (
+    get_param_tensor,
+    get_tensor_name,
+    is_param_node,
+)
 from executorch.exir import ExportedProgram
 from executorch.exir.dialects._ops import ops as exir_ops
 from executorch.exir.pass_base import PassResult
+from torch.export.graph_signature import InputKind
 
 from torch.nn.utils.fusion import fuse_conv_bn_weights
 
@@ -28,7 +37,7 @@ class FuseBatchNormWithConvPass(XNNPACKPass):
 
     def call(self, graph_module: torch.fx.GraphModule):
         graph = graph_module.graph
-        counter = 0
+        constant_placeholders_to_delete = set()
         for conv in graph.nodes:
             # We want to discover a chain of conv -> batch_norm.
             # Only proceed if the current node is a conv node, and has a single
@@ -55,9 +64,11 @@ def call(self, graph_module: torch.fx.GraphModule):
             assert len(conv.args) == 9
 
             conv_weight = get_param_tensor(self.exported_program, conv.args[1])
+            conv_weight_name = get_tensor_name(self.exported_program, conv.args[1])
             assert conv_weight is not None
 
             conv_bias = get_param_tensor(self.exported_program, conv.args[2])
+            conv_bias_name = get_tensor_name(self.exported_program, conv.args[2])
 
             # Get the parameters from the batchnorm op
             assert (
@@ -95,32 +106,57 @@ def call(self, graph_module: torch.fx.GraphModule):
                 bn_bias,
                 is_transpose,
             )
+            fused_weight_name = (conv_weight_name + "_fused_bn").replace(".", "_")
+            if conv_bias_name == "":
+                fused_bias_name = (conv_weight_name + "_bias_fused_bn").replace(
+                    ".", "_"
+                )
+            else:
+                fused_bias_name = (conv_bias_name + "_fused_bn").replace(".", "_")
 
             # Modify the graph by updating the weight and bias of conv op
             # with the fused weight and bias params, and replacing all the users
             # of getitem(batchnorm) with the conv op.
-            with graph.inserting_before(conv):
-                fused_weight_name = f"_fused_with_bn_weight_{counter}"
-                graph_module.register_parameter(fused_weight_name, fused_weight)
-                fused_weight_node = graph.get_attr(fused_weight_name)
-                fused_bias_name = f"_fused_with_bn_bias_{counter}"
-                graph_module.register_parameter(fused_bias_name, fused_bias)
-                fused_bias_node = graph.get_attr(fused_bias_name)
-
-            # Update the weight and bias of conv op
-            conv_args = list(conv.args) + ([None] if len(conv.args) == 2 else [])
-            conv_args[1] = fused_weight_node
-            conv_args[2] = fused_bias_node
-            conv.args = tuple(conv_args)
+            with graph.inserting_before(conv.args[1]):
+                fused_conv_weight_node = create_constant_placeholder(
+                    exp_program=self.exported_program,
+                    graph=graph_module.graph,
+                    kind=InputKind.PARAMETER,
+                    name=fused_weight_name,
+                    data=fused_weight,
+                )
+                if fused_bias is not None:
+                    fused_conv_bias_node = create_constant_placeholder(
+                        exp_program=self.exported_program,
+                        graph=graph_module.graph,
+                        kind=InputKind.PARAMETER,
+                        name=fused_bias_name,
+                        data=fused_bias,
+                    )
+                else:
+                    fused_conv_bias_node = None
+
+                conv.args = (
+                    conv.args[0],
+                    fused_conv_weight_node,
+                    fused_conv_bias_node,
+                    *conv.args[3:],
+                )
+
             # Remove any use of batchnorm from the graph
             for user in bn.users.copy():
                 assert user.target == operator.getitem
                 user.replace_all_uses_with(conv)
                 graph.erase_node(user)
 
             graph.erase_node(bn)
+            constant_placeholders_to_delete.update(conv.args[1:3] + bn.args[1:5])
 
-            counter += 1
+        if len(constant_placeholders_to_delete) > 0:
+            graph_module.graph.eliminate_dead_code()
+            for node in constant_placeholders_to_delete:
+                if (node is not None) and (len(node.users) == 0):
+                    delete_constant_placeholder(self.exported_program, node)
 
         graph_module.recompile()
         # To Regenerate meta data and shape information, retrace module

backends/xnnpack/operators/node_visitor.py

@@ -34,20 +34,23 @@
     check_or_raise,
     get_input_node,
     get_param_tensor,
+    get_tensor_name,
     is_param_node,
     PERM_NCHW_TO_NHWC,
 )
 
-from executorch.backends.xnnpack.utils.xnnpack_constants import XNN_INVALID_VALUE_ID
+from executorch.backends.xnnpack.utils.xnnpack_constants import (
+    UINT64_MAX,
+    XNN_INVALID_VALUE_ID,
+)
+from executorch.exir._serialize._named_data_store import NamedDataStore
 from torch.export import ExportedProgram
 
 XNN_TYPE_MAP = {
     torch.float32: XNNDatatype.xnn_datatype_fp32,
 }
 
 from executorch.backends.xnnpack.serialization.xnnpack_graph_serialize import (
-    _aligned_size,
-    _pad_to,
     CONSTANT_TENSOR_ALIGNMENT,
 )
 
@@ -86,11 +89,11 @@ def __init__(
         self,
         exported_program: ExportedProgram,
         external_ids: Dict,
-        constant_data_bytes: bytearray,
+        named_data_store: NamedDataStore,
     ) -> None:
         self._external_ids = external_ids or {}
         self._exported_program = exported_program or None
-        self._constant_data_bytes = constant_data_bytes
+        self._named_data_store = named_data_store
 
     @property
     def external_ids(self) -> Dict:
@@ -579,11 +582,16 @@ def get_serialized_buffer_index(
             ctypes.POINTER(array_type),
         ).contents
 
-        offset = len(self._constant_data_bytes)
+        named_key = get_tensor_name(self.exported_program, get_attr_node)
+        if named_key == "":
+            raise ValueError(f"Tensor from node: {get_attr_node} has no name")
+
         size = const_val.untyped_storage().nbytes()
-        xnn_graph.constant_data.append(ConstantDataOffset(offset=offset, size=size))
-        self._constant_data_bytes.extend(
-            _pad_to(bytes(array), _aligned_size(size, CONSTANT_TENSOR_ALIGNMENT))
+        xnn_graph.constant_data.append(
+            ConstantDataOffset(offset=UINT64_MAX, size=size, named_key=named_key)
+        )
+        self._named_data_store.add_named_data(
+            named_key, bytes(array), alignment=CONSTANT_TENSOR_ALIGNMENT
         )
 
         return buffer_idx

backends/xnnpack/serialization/schema.fbs

@@ -316,11 +316,20 @@ table XNNLeakyReLU {
 table ConstantDataOffset {
   // Constant data offsets are relative to the constant data base offset provided
   // in the XNNPACKHeader.
+  // named_key and offset are mutually exclusive, meaning only one of these values
+  // are valid. If the named key is a non-empty string, then the offset must be UINT64_MAX.
+  // If the offset is not UINT64_MAX, then the named key must be an empty string
   offset: uint64;
 
   // The size in bytes of valid data starting at the offset. The constant data
   // may be followed by padding before the next piece of constant data
   size: uint64;
+
+  // unique string id used to query the offset from the named data store.
+  // named_key and offset are mutually exclusive, meaning only one of these values
+  // are valid. If the named key is a non-empty string, then the offset must be UINT64_MAX.
+  // If the offset is not UINT64_MAX, then the named key must be an empty string
+  named_key: string;
 }
 
 table XNNGraph {

backends/xnnpack/serialization/xnnpack_graph_schema.py

@@ -470,6 +470,7 @@ class XValue:
 class ConstantDataOffset:
     offset: int
     size: int
+    named_key: str = ""
 
 
 @dataclass

backends/xnnpack/utils/gen_xnnpack_constants.sh

@@ -26,5 +26,6 @@
 } > xnnpack_constants.py
 
 echo UINT32_MAX = 4294967295 >> xnnpack_constants.py
+echo UINT64_MAX = 18446744073709551615 >> xnnpack_constants.py
 awk '/^#define\s+XNN_/ { print $2,"=",$3} ' "$1"/include/xnnpack.h >> xnnpack_constants.py
 if ! grep -qc "^XNN_" xnnpack_constants.py; then false; fi

backends/xnnpack/utils/utils.py

@@ -131,6 +131,22 @@ def get_param_tensor(
     raise RuntimeError(f"unsupported param type, {node.op}.")
 
 
+def get_tensor_name(exp_prog: ExportedProgram, node: torch.fx.Node) -> str:
+    if node is None:
+        return ""
+    if is_param(exp_prog, node):
+        return exp_prog.graph_signature.inputs_to_parameters[node.name]
+    elif is_buffer(exp_prog, node):
+        return exp_prog.graph_signature.inputs_to_buffers[node.name]
+    elif is_lifted_tensor_constant(exp_prog, node):
+        return exp_prog.graph_signature.inputs_to_lifted_tensor_constants[node.name]
+    else:
+        assert isinstance(node.target, str)
+        return node.target
+
+    return ""
+
+
 def get_source_fn(node: torch.fx.Node) -> Optional[torch.fx.Node]:
     """
     Returns the source fn of the given node, return None if something goes wrong

backends/xnnpack/utils/xnnpack_constants.py

@@ -6,8 +6,11 @@
 
 # Auto-generated by gen_xnnpack_constants.sh script. Do not modify
 UINT32_MAX = 4294967295
+UINT64_MAX = 18446744073709551615
+XNN_EXTRA_BYTES = 128
 XNN_EXTRA_BYTES = 16
 XNN_MAX_TENSOR_DIMS = 6
+XNN_INVALID_VALUE_ID = UINT32_MAX
 XNN_FLAG_HINT_SPARSE_INFERENCE = 0x00000001
 XNN_FLAG_HINT_FP16_INFERENCE = 0x00000002
 XNN_FLAG_FORCE_FP16_INFERENCE = 0x00000004
@@ -26,7 +29,8 @@
 XNN_FLAG_YIELD_WORKERS = 0x00000010
 XNN_FLAG_TRANSIENT_INDIRECTION_BUFFER = 0x00000020
 XNN_FLAG_KEEP_DIMS = 0x00000040
-XNN_EXTRA_QUANTIZATION_PARAMS = 8
+XNN_EXTRA_QUANTIZATION_PARAMS = 10
+XNN_MIN_BLOCKSIZE = 32
 XNN_VALUE_FLAG_EXTERNAL_INPUT = 0x00000001
 XNN_VALUE_FLAG_EXTERNAL_OUTPUT = 0x00000002
 XNN_VALUE_FLAG_PERSISTENT = 0x00000004

backends/xnnpack/xnnpack_preprocess.py

@@ -31,6 +31,7 @@
     XNN_VALUE_FLAG_EXTERNAL_INPUT,
     XNN_VALUE_FLAG_EXTERNAL_OUTPUT,
 )
+from executorch.exir._serialize._named_data_store import NamedDataStore
 
 from executorch.exir.backend.backend_details import (
     BackendDetails,
@@ -103,7 +104,7 @@ def preprocess(
         edge_program: ExportedProgram,
         compile_specs: List[CompileSpec],
     ) -> PreprocessResult:
-
+        named_data_store = NamedDataStore()
         xnnpack_edge_compile_config = get_xnnpack_edge_compile_config()
 
         # Need to wrap EP here because xnnpack does addmm to linear
@@ -162,7 +163,7 @@ def preprocess(
         )
 
         constant_data_bytes = bytearray()
-        node_visitors = get_node_visitors(ep, node_to_external_map, constant_data_bytes)
+        node_visitors = get_node_visitors(ep, node_to_external_map, named_data_store)
 
         for node in graph_module.graph.nodes:
             if node.op == "call_function":
@@ -191,4 +192,5 @@ def preprocess(
                 xnnpack_graph, constant_data_bytes
             ),
             debug_handle_map={},
+            data_store_output=named_data_store.get_named_data_store_output(),
         )