MLBEDSW-3019: Add profiling debug database

 - Added mechanism to track input to output graph transforms for
   debugging the resultant command stream.
 - Provides base implementation for MLBEDSW-2661

Signed-off-by: Tim Hall <tim.hall@arm.com>
Change-Id: I2dfe8a409fbde7ad0282bfab5acb11ba1c8b82d8
diff --git a/ethosu/vela/debug_database.py b/ethosu/vela/debug_database.py
new file mode 100644
index 0000000..b5852cd
--- /dev/null
+++ b/ethosu/vela/debug_database.py
@@ -0,0 +1,121 @@
+# Copyright (C) 2020 Arm Limited or its affiliates. All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the License); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an AS IS BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import csv
+import io
+
+import lxml.etree as xml
+
+from . import numeric_util
+from .operation import Operation
+
+
+class DebugDatabase:
+    NULLREF = -1
+    show_warnings = False
+
+    SOURCE_TABLE = "source"
+    _sourceUID = {}
+    _sourceHeaders = ["id", "operator", "kernel_w", "kernel_h", "ofm_w", "ofm_h", "ofm_d"]
+    _sourceTable = []
+
+    OPTIMISED_TABLE = "optimised"
+    _optimisedUID = {}
+    _optimisedHeaders = ["id", "source_id", "operator", "kernel_w", "kernel_h", "ofm_w", "ofm_h", "ofm_d"]
+    _optimisedTable = []
+
+    QUEUE_TABLE = "queue"
+    _queueHeaders = ["offset", "cmdstream_id", "optimised_id"]
+    _queueTable = []
+
+    STREAM_TABLE = "cmdstream"
+    _streamUID = {}
+    _streamHeaders = ["id", "file_offset"]
+    _streamTable = []
+
+    @classmethod
+    def add_source(cls, op: Operation):
+        assert isinstance(op, Operation)
+        uid = len(cls._sourceUID)
+        cls._sourceUID[op] = uid
+        ofm_shape = numeric_util.full_shape(3, op.outputs[0].shape, 1)
+        cls._sourceTable.append(
+            [uid, op.type, op.kernel.width, op.kernel.height, ofm_shape[-2], ofm_shape[-3], ofm_shape[-1]]
+        )
+
+    @classmethod
+    def add_optimised(cls, parent: Operation, op: Operation):
+        assert isinstance(parent, Operation) and isinstance(op, Operation)
+        if op not in cls._optimisedUID:
+            if parent not in cls._sourceUID:
+                # The the parent wasn't in the source network try to look it
+                # up in the optimised network and use that op's source parent.
+                if parent in cls._optimisedUID:
+                    src_uid = cls._optimisedUID[parent][1]
+                else:
+                    if DebugDatabase.show_warnings:
+                        print("Debug Database: Associated parent '{0}' not in network".format(parent.type))
+                    src_uid = DebugDatabase.NULLREF
+            else:
+                src_uid = cls._sourceUID[parent]
+            uid = len(cls._optimisedUID)
+            cls._optimisedUID[op] = (uid, src_uid)
+            ofm_shape = numeric_util.full_shape(3, op.outputs[0].shape, 1)
+            cls._optimisedTable.append(
+                [uid, src_uid, op.type, op.kernel.width, op.kernel.height, ofm_shape[-2], ofm_shape[-3], ofm_shape[-1]]
+            )
+
+    @classmethod
+    def add_stream(cls, key):
+        if key not in cls._streamUID:
+            uid = len(cls._streamUID)
+            cls._streamUID[key] = uid
+        return uid
+
+    @classmethod
+    def set_stream_offset(cls, key, file_offset):
+        assert key in cls._streamUID
+        uid = cls._streamUID[key]
+        cls._streamTable.append([uid, file_offset])
+
+    @classmethod
+    def add_command(cls, stream_id, offset, op: Operation):
+        assert stream_id < len(cls._streamUID)
+        assert op in cls._optimisedUID, "Optimised operator must exist before code generation"
+        optimised_id = cls._optimisedUID[op][0]
+        cls._queueTable.append([offset, stream_id, optimised_id])
+
+    @classmethod
+    def _write_table(cls, root, name, headers, table):
+        # Convert table to CSV
+        out = io.StringIO()
+        writer = csv.writer(out, quoting=csv.QUOTE_NONNUMERIC)
+        writer.writerow(headers)
+        writer.writerows(table)
+
+        # Package table into XML output
+        table = xml.SubElement(root, "table", {"name": name})
+        table.text = xml.CDATA(out.getvalue())
+
+    @classmethod
+    def write(cls, file_path, input_file, output_file):
+        root = xml.Element("debug", {"source": input_file, "optimised": output_file})
+
+        cls._write_table(root, cls.SOURCE_TABLE, cls._sourceHeaders, cls._sourceTable)
+        cls._write_table(root, cls.OPTIMISED_TABLE, cls._optimisedHeaders, cls._optimisedTable)
+        cls._write_table(root, cls.QUEUE_TABLE, cls._queueHeaders, cls._queueTable)
+        cls._write_table(root, cls.STREAM_TABLE, cls._streamHeaders, cls._streamTable)
+
+        xml.ElementTree(root).write(file_path, encoding="utf-8", xml_declaration=True, pretty_print=True)