MLBEDSW-3771: Updated to TF 2.4 flatbuffer schema

Updated tflite loader and mappings from tensorflow 2.3 to tensorflow 2.4

Signed-off-by: Tim Hall <tim.hall@arm.com>
Change-Id: I55884000ee139baf639bb0377008e0534f72fe94

13 files changed, 206 insertions, 6 deletions

diff --git a/README.md b/README.md
index 586885c..81bb0a0 100644
--- a/README.md
+++ b/README.md
@@ -25,7 +25,9 @@ compiled model.
 
 ## TensorFlow Support
 
-Vela supports TensorFlow 2.3.0
+* Vela 2.1.0 to current supports TensorFlow 2.4
+* Vela 2.0.0 to 2.0.1 supports TensorFlow 2.3
+* Vela 0.1.0 to 1.2.0 supports TensorFlow 2.1
 
 ## Environment
 
diff --git a/ethosu/vela/operation.py b/ethosu/vela/operation.py
index 963d9e6..09371b7 100644
--- a/ethosu/vela/operation.py
+++ b/ethosu/vela/operation.py
@@ -145,6 +145,7 @@ class Op(Enum):
     )
     Conv2DBias = OperatorInfo(block_type=NpuBlockType.ConvolutionMxN, indices=IFM_WEIGHTS_BIAS_INDICES)
     Cos = OperatorInfo()
+    Cumsum = OperatorInfo()
     Custom = OperatorInfo()  # Custom 3rd party operator, only used in CPU subgraphs
     CustomNpuOp = OperatorInfo()  # NPU custom operator, only used in CPU subgraphs
     DMA = OperatorInfo()
diff --git a/ethosu/vela/tflite/BuiltinOperator.py b/ethosu/vela/tflite/BuiltinOperator.py
index fb23155..73fed9b 100644
--- a/ethosu/vela/tflite/BuiltinOperator.py
+++ b/ethosu/vela/tflite/BuiltinOperator.py
@@ -130,4 +130,6 @@ class BuiltinOperator(object):
     DENSIFY = 124
     SEGMENT_SUM = 125
     BATCH_MATMUL = 126
+    PLACEHOLDER_FOR_GREATER_OP_CODES = 127
+    CUMSUM = 128
 
diff --git a/ethosu/vela/tflite/BuiltinOptions.py b/ethosu/vela/tflite/BuiltinOptions.py
index 6f0aab0..6be2d43 100644
--- a/ethosu/vela/tflite/BuiltinOptions.py
+++ b/ethosu/vela/tflite/BuiltinOptions.py
@@ -105,4 +105,5 @@ class BuiltinOptions(object):
     DensifyOptions = 99
     SegmentSumOptions = 100
     BatchMatMulOptions = 101
+    CumsumOptions = 102
 
diff --git a/ethosu/vela/tflite/CumsumOptions.py b/ethosu/vela/tflite/CumsumOptions.py
new file mode 100644
index 0000000..33e086e
--- /dev/null
+++ b/ethosu/vela/tflite/CumsumOptions.py
@@ -0,0 +1,38 @@
+# automatically generated by the FlatBuffers compiler, do not modify
+
+# namespace: tflite
+
+import flatbuffers
+
+class CumsumOptions(object):
+    __slots__ = ['_tab']
+
+    @classmethod
+    def GetRootAsCumsumOptions(cls, buf, offset):
+        n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, offset)
+        x = CumsumOptions()
+        x.Init(buf, n + offset)
+        return x
+
+    # CumsumOptions
+    def Init(self, buf, pos):
+        self._tab = flatbuffers.table.Table(buf, pos)
+
+    # CumsumOptions
+    def Exclusive(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return bool(self._tab.Get(flatbuffers.number_types.BoolFlags, o + self._tab.Pos))
+        return False
+
+    # CumsumOptions
+    def Reverse(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(6))
+        if o != 0:
+            return bool(self._tab.Get(flatbuffers.number_types.BoolFlags, o + self._tab.Pos))
+        return False
+
+def CumsumOptionsStart(builder): builder.StartObject(2)
+def CumsumOptionsAddExclusive(builder, exclusive): builder.PrependBoolSlot(0, exclusive, 0)
+def CumsumOptionsAddReverse(builder, reverse): builder.PrependBoolSlot(1, reverse, 0)
+def CumsumOptionsEnd(builder): return builder.EndObject()
diff --git a/ethosu/vela/tflite/Model.py b/ethosu/vela/tflite/Model.py
index cc9991b..52aac02 100644
--- a/ethosu/vela/tflite/Model.py
+++ b/ethosu/vela/tflite/Model.py
@@ -134,7 +134,27 @@ class Model(object):
             return self._tab.VectorLen(o)
         return 0
 
-def ModelStart(builder): builder.StartObject(7)
+    # Model
+    def SignatureDefs(self, j):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(18))
+        if o != 0:
+            x = self._tab.Vector(o)
+            x += flatbuffers.number_types.UOffsetTFlags.py_type(j) * 4
+            x = self._tab.Indirect(x)
+            from .SignatureDef import SignatureDef
+            obj = SignatureDef()
+            obj.Init(self._tab.Bytes, x)
+            return obj
+        return None
+
+    # Model
+    def SignatureDefsLength(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(18))
+        if o != 0:
+            return self._tab.VectorLen(o)
+        return 0
+
+def ModelStart(builder): builder.StartObject(8)
 def ModelAddVersion(builder, version): builder.PrependUint32Slot(0, version, 0)
 def ModelAddOperatorCodes(builder, operatorCodes): builder.PrependUOffsetTRelativeSlot(1, flatbuffers.number_types.UOffsetTFlags.py_type(operatorCodes), 0)
 def ModelStartOperatorCodesVector(builder, numElems): return builder.StartVector(4, numElems, 4)
@@ -147,4 +167,6 @@ def ModelAddMetadataBuffer(builder, metadataBuffer): builder.PrependUOffsetTRela
 def ModelStartMetadataBufferVector(builder, numElems): return builder.StartVector(4, numElems, 4)
 def ModelAddMetadata(builder, metadata): builder.PrependUOffsetTRelativeSlot(6, flatbuffers.number_types.UOffsetTFlags.py_type(metadata), 0)
 def ModelStartMetadataVector(builder, numElems): return builder.StartVector(4, numElems, 4)
+def ModelAddSignatureDefs(builder, signatureDefs): builder.PrependUOffsetTRelativeSlot(7, flatbuffers.number_types.UOffsetTFlags.py_type(signatureDefs), 0)
+def ModelStartSignatureDefsVector(builder, numElems): return builder.StartVector(4, numElems, 4)
 def ModelEnd(builder): return builder.EndObject()
diff --git a/ethosu/vela/tflite/OperatorCode.py b/ethosu/vela/tflite/OperatorCode.py
index dd525f5..5a0ba2a 100644
--- a/ethosu/vela/tflite/OperatorCode.py
+++ b/ethosu/vela/tflite/OperatorCode.py
@@ -19,7 +19,7 @@ class OperatorCode(object):
         self._tab = flatbuffers.table.Table(buf, pos)
 
     # OperatorCode
-    def BuiltinCode(self):
+    def DeprecatedBuiltinCode(self):
         o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
         if o != 0:
             return self._tab.Get(flatbuffers.number_types.Int8Flags, o + self._tab.Pos)
@@ -39,8 +39,16 @@ class OperatorCode(object):
             return self._tab.Get(flatbuffers.number_types.Int32Flags, o + self._tab.Pos)
         return 1
 
-def OperatorCodeStart(builder): builder.StartObject(3)
-def OperatorCodeAddBuiltinCode(builder, builtinCode): builder.PrependInt8Slot(0, builtinCode, 0)
+    # OperatorCode
+    def BuiltinCode(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(10))
+        if o != 0:
+            return self._tab.Get(flatbuffers.number_types.Int32Flags, o + self._tab.Pos)
+        return 0
+
+def OperatorCodeStart(builder): builder.StartObject(4)
+def OperatorCodeAddDeprecatedBuiltinCode(builder, deprecatedBuiltinCode): builder.PrependInt8Slot(0, deprecatedBuiltinCode, 0)
 def OperatorCodeAddCustomCode(builder, customCode): builder.PrependUOffsetTRelativeSlot(1, flatbuffers.number_types.UOffsetTFlags.py_type(customCode), 0)
 def OperatorCodeAddVersion(builder, version): builder.PrependInt32Slot(2, version, 1)
+def OperatorCodeAddBuiltinCode(builder, builtinCode): builder.PrependInt32Slot(3, builtinCode, 0)
 def OperatorCodeEnd(builder): return builder.EndObject()
diff --git a/ethosu/vela/tflite/SignatureDef.py b/ethosu/vela/tflite/SignatureDef.py
new file mode 100644
index 0000000..149f8fc
--- /dev/null
+++ b/ethosu/vela/tflite/SignatureDef.py
@@ -0,0 +1,82 @@
+# automatically generated by the FlatBuffers compiler, do not modify
+
+# namespace: tflite
+
+import flatbuffers
+
+class SignatureDef(object):
+    __slots__ = ['_tab']
+
+    @classmethod
+    def GetRootAsSignatureDef(cls, buf, offset):
+        n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, offset)
+        x = SignatureDef()
+        x.Init(buf, n + offset)
+        return x
+
+    # SignatureDef
+    def Init(self, buf, pos):
+        self._tab = flatbuffers.table.Table(buf, pos)
+
+    # SignatureDef
+    def Inputs(self, j):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            x = self._tab.Vector(o)
+            x += flatbuffers.number_types.UOffsetTFlags.py_type(j) * 4
+            x = self._tab.Indirect(x)
+            from .TensorMap import TensorMap
+            obj = TensorMap()
+            obj.Init(self._tab.Bytes, x)
+            return obj
+        return None
+
+    # SignatureDef
+    def InputsLength(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return self._tab.VectorLen(o)
+        return 0
+
+    # SignatureDef
+    def Outputs(self, j):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(6))
+        if o != 0:
+            x = self._tab.Vector(o)
+            x += flatbuffers.number_types.UOffsetTFlags.py_type(j) * 4
+            x = self._tab.Indirect(x)
+            from .TensorMap import TensorMap
+            obj = TensorMap()
+            obj.Init(self._tab.Bytes, x)
+            return obj
+        return None
+
+    # SignatureDef
+    def OutputsLength(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(6))
+        if o != 0:
+            return self._tab.VectorLen(o)
+        return 0
+
+    # SignatureDef
+    def MethodName(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(8))
+        if o != 0:
+            return self._tab.String(o + self._tab.Pos)
+        return None
+
+    # SignatureDef
+    def Key(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(10))
+        if o != 0:
+            return self._tab.String(o + self._tab.Pos)
+        return None
+
+def SignatureDefStart(builder): builder.StartObject(4)
+def SignatureDefAddInputs(builder, inputs): builder.PrependUOffsetTRelativeSlot(0, flatbuffers.number_types.UOffsetTFlags.py_type(inputs), 0)
+def SignatureDefStartInputsVector(builder, numElems): return builder.StartVector(4, numElems, 4)
+def SignatureDefAddOutputs(builder, outputs): builder.PrependUOffsetTRelativeSlot(1, flatbuffers.number_types.UOffsetTFlags.py_type(outputs), 0)
+def SignatureDefStartOutputsVector(builder, numElems): return builder.StartVector(4, numElems, 4)
+def SignatureDefAddMethodName(builder, methodName): builder.PrependUOffsetTRelativeSlot(2, flatbuffers.number_types.UOffsetTFlags.py_type(methodName), 0)
+def SignatureDefAddKey(builder, key): builder.PrependUOffsetTRelativeSlot(3, flatbuffers.number_types.UOffsetTFlags.py_type(key), 0)
+def SignatureDefEnd(builder): return builder.EndObject()
diff --git a/ethosu/vela/tflite/TensorMap.py b/ethosu/vela/tflite/TensorMap.py
new file mode 100644
index 0000000..e9b036d
--- /dev/null
+++ b/ethosu/vela/tflite/TensorMap.py
@@ -0,0 +1,38 @@
+# automatically generated by the FlatBuffers compiler, do not modify
+
+# namespace: tflite
+
+import flatbuffers
+
+class TensorMap(object):
+    __slots__ = ['_tab']
+
+    @classmethod
+    def GetRootAsTensorMap(cls, buf, offset):
+        n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, offset)
+        x = TensorMap()
+        x.Init(buf, n + offset)
+        return x
+
+    # TensorMap
+    def Init(self, buf, pos):
+        self._tab = flatbuffers.table.Table(buf, pos)
+
+    # TensorMap
+    def Name(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return self._tab.String(o + self._tab.Pos)
+        return None
+
+    # TensorMap
+    def TensorIndex(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(6))
+        if o != 0:
+            return self._tab.Get(flatbuffers.number_types.Uint32Flags, o + self._tab.Pos)
+        return 0
+
+def TensorMapStart(builder): builder.StartObject(2)
+def TensorMapAddName(builder, name): builder.PrependUOffsetTRelativeSlot(0, flatbuffers.number_types.UOffsetTFlags.py_type(name), 0)
+def TensorMapAddTensorIndex(builder, tensorIndex): builder.PrependUint32Slot(1, tensorIndex, 0)
+def TensorMapEnd(builder): return builder.EndObject()
diff --git a/ethosu/vela/tflite_mapping.py b/ethosu/vela/tflite_mapping.py
index 6fcbb95..c1e45c0 100644
--- a/ethosu/vela/tflite_mapping.py
+++ b/ethosu/vela/tflite_mapping.py
@@ -40,6 +40,7 @@ from .tflite import ConcatEmbeddingsOptions
 from .tflite import ConcatenationOptions
 from .tflite import Conv2DOptions
 from .tflite import CosOptions
+from .tflite import CumsumOptions
 from .tflite import DensifyOptions
 from .tflite import DepthToSpaceOptions
 from .tflite import DepthwiseConv2DOptions
@@ -278,6 +279,7 @@ builtin_options_map = {
     BuiltinOptions.SelectV2Options: SelectV2Options.SelectV2Options,
     BuiltinOptions.WhileOptions: WhileOptions.WhileOptions,
     BuiltinOptions.BatchMatMulOptions: BatchMatMulOptions.BatchMatMulOptions,
+    BuiltinOptions.CumsumOptions: CumsumOptions.CumsumOptions,
 }
 
 builtin_options_inv_map = inverse_map(builtin_options_map)
@@ -690,6 +692,7 @@ builtin_operator_map = {
     BuiltinOperator.DENSIFY: (Op.Densify, OptionsSerializer("DensifyOptions")),
     BuiltinOperator.SEGMENT_SUM: (Op.SegmentSum, OptionsSerializer("SegmentSumOptions")),
     BuiltinOperator.BATCH_MATMUL: (Op.BatchMatMul, OptionsSerializer("BatchMatMulOptions", ("adj_x", "adj_y"))),
+    BuiltinOperator.CUMSUM: (Op.Cumsum, OptionsSerializer("CumsumOptions", ("exclusive", "reverse"))),
     BuiltinOperator.CUSTOM: (Op.Custom, CustomOptionsSerializer()),
 }
 
diff --git a/ethosu/vela/tflite_reader.py b/ethosu/vela/tflite_reader.py
index 45397c2..ae99c33 100644
--- a/ethosu/vela/tflite_reader.py
+++ b/ethosu/vela/tflite_reader.py
@@ -266,6 +266,8 @@ class TFLiteGraph:
 
     def parse_operator_code(self, code):
         c = code.BuiltinCode()
+        if c == 0:
+            c = code.DeprecatedBuiltinCode()
         if c not in builtin_operator_map:
             raise InputFileError(
                 self.name, f"The input file contains operator code '{c}' which is currently not supported"
diff --git a/ethosu/vela/tflite_writer.py b/ethosu/vela/tflite_writer.py
index 82a063f..e190a74 100644
--- a/ethosu/vela/tflite_writer.py
+++ b/ethosu/vela/tflite_writer.py
@@ -193,6 +193,7 @@ class TFLiteSerialiser:
             self.operator_code_map[op_type] = (idx, tf_code, opt_serializer)
 
         OperatorCode.OperatorCodeStart(builder)
+        OperatorCode.OperatorCodeAddDeprecatedBuiltinCode(builder, tf_code if tf_code < 127 else 127)
         OperatorCode.OperatorCodeAddBuiltinCode(builder, tf_code)
         if custom_code_offset is not None:
             OperatorCode.OperatorCodeAddCustomCode(builder, custom_code_offset)
diff --git a/setup.py b/setup.py
index c62944a..f67d42e 100644
--- a/setup.py
+++ b/setup.py
@@ -78,7 +78,7 @@ setup(
     packages=find_namespace_packages(include=["ethosu.*"]),
     python_requires="~=3.6",  # We support only 3.6+
     install_requires=[
-        "flatbuffers==1.11.0",
+        "flatbuffers==1.12.0",
         "numpy>=1.16.6",
         "numpy>=1.16.6,<1.19.4 ; platform_system=='Windows'",
         "lxml>=4.5.1",