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+######################
+Code size analyze tool
+######################
+
+.. contents:: Table of Contents
+
+These are scripts to dump ARMCLANG complie map file detail information and get
+the change between two different build results. The features are:
+
+* Get a database to implement data tables from ARMCLANG or GNUARM map file.
+* Supply an UI for developers to scan sorted information of sections, libraries,
+  object files, functions and data. It can help analyze the biggest or smallest
+  targets in certain image. It can also help search functions or data to locate
+  their address and detail information.
+* Diff two databases to see the code size increasement or decreasement.
+
+***************
+Install sqlite3
+***************
+
+Linux
+=====
+Install sqlite3 for python.
+
+.. code-block:: bash
+
+    sudo apt-get install python3-dev libmysqlclient-dev
+    pip install mysqlclient
+
+
+*****
+Usage
+*****
+
+The command is:
+
+.. code-block:: bash
+
+    python3 code_size_analyze.py -i <map file path> --gnuarm
+    python3 code_size_analyze.py -i <map file path> --armcc
+    python3 code_size_analyze.py --ui
+
+It is required to input map file path for the script before show the UI. While
+input the map file, compiler information such as ``--gnuarm`` or ``--armcc``
+is required.
+
+keys
+====
+
+The script ui.py supplies a menu to choose what developers may be interested.
+There are several keys to move cursor.
+
+* UP: Move UP, mouse scrolling up is same.
+* DOWN: Move down, mouse scrolling down is same.
+* RIGHT: Move right.
+* LEFT: Move left.
+* Enter: Move to next page if it can be unfolded.
+* ``Q`` or ``q``: Escape to previous page or close script if it in top menu.
+
+Search
+======
+
+In ``Function detail`` and ``library detail`` pages, developers can search for
+specific target with key word of target name. Press ``:`` to start search and
+enter the name in the last line of window. All the targets with key word will
+be given.
+
+You can also search or dump the target in command line without Ui, for example:
+.. code-block:: bash
+
+    python3 code_size_analyze.py --search_func <func_name>
+
+All the features provided by UI can be used in command line too. Enter ``-h`` to
+get the help information and choose the option to use.
+
+Save
+====
+
+In any page, press ``s`` or ``S`` to start enter output file name to save the
+content of this page.
+
+Diff
+====
+
+Use ``code_size_diff.py`` to diff two diffrent build results with same compiler.
+Firstly, use ``code_size_analyze.py`` to prepare two different databases. For
+example:
+
+.. code-block:: bash
+
+    cd <TF-M workspace>
+    git checkout branch1
+    # Build with ARMCLANG
+    python3 code_size_analyze.py -i <map file 1> --armcc
+    mv data.db output/branch1.db
+
+    # Do the same steps to create branch2.db
+
+Then compare two database with the diff tool, the branch1 is base.
+
+.. code-block:: bash
+
+    python3 code_size_diff.py -i output/branch1.db output/branch2.db -a
+    Code size:  +++         48928   B               47.78   KB
+    RO data:    +++         29440   B               28.75   KB
+    RW data:    ---         64      B               0.06    KB
+    ZI data:    ---         500     B               0.49    KB
+    Flash size: +++         78304   B               76.47   KB
+    RAM size:   ---         564     B               0.55    KB
+
+The summary information change will be printed. Enter ``-h`` to get more usages
+of diff tool.
+
+--------------
+
+*Copyright (c) 2021, Arm Limited. All rights reserved.*