DB4HLS

Herein you can find the sources and the instruction to perform parallel DSEs using a DSL thought for an efficient definition of large design spaces, and to concurrently execute the synthesis with VivadoHLS using gnu-parallel. Moreover, SQL scripts to interact with the DB4HLS database are provided in order to retrieve data from it.

DB prerequisites:

mysql installed on your machine

DB4HLS framework prerequisites:

python3
gnu-parallel

How to use DB4HLS

After having installed mysql on your machine, import the DB4HLS schema available from the follwing link into your mysql database.

Firstly, run mysql and create an empty db4hls database:

CREATE DATABASE db4hls;

Then, close mysql and import the db4hls.sql content in your database.

mysql -u <your_username> -p<your_password> db4hls < db4hls.sql

Now, by running msql you can access the content of DB4HLS and query it in order to access its data. Please refer to the tutorial for more details regarding the SQL scripts and to the DB4HLS documentation for more info about the database structure.

An sql script can be executed running the follwing instruction:

mysql -u <username> -p<username_password> -e "<sql_query>"

Example:

mysql -u lorenzo -pmypassword -e "SELECT * FROM db4hls.design;"

Will return the following output:

+--------------------+-----------+--------------+-----------------------------+------------------------+----------------+
| name               | id_design | id_algorithm | relative_path               | src_files              | testbench_file |
+--------------------+-----------+--------------+-----------------------------+------------------------+----------------+
| aes                |       428 |            1 | MachSuite/aes/aes           | aes.c, aes.h           |                |
| notable-noexpanded |         1 |            1 | MachSuite/aes/aes           | aes.c, aes.h           | aes_test.c     |
| table              |         3 |            1 | MachSuite/aes/aes           | aes.c, aes.h           | aes_test.c     |
| table-noexpanded   |         2 |            1 | MachSuite/aes/aes           | aes.c, aes.h           | aes_test.c     |
| ncubed             |         6 |            6 | MachSuite/gemm/ncubed       | gemm.c, gemm.h         |                |
| stencil2d          |       299 |          299 | MachSuite/stencil/stencil2d | stencil.c, stencil.h   |                |
| radix              |       335 |          335 | MachSuite/sort/radix        | sort.c, sort.h         |                |
| update             |       380 |          335 | MachSuite/sort/radix        | sort.c, sort.h         |                |
| backprop           |       365 |          338 | MachSuite/backprop/backprop | backprop.c, backprop.h |                |
| bulk               |       371 |          371 | MachSuite/bfs/bulk          | bfs.c, bfs.h           |                |
| fft                |       394 |          394 | MachSuite/fft/strided       | fft.c, fft.h           |                |
| strided            |       395 |          394 | MachSuite/fft/strided       | fft.c, fft.h           |                |
| knn                |       398 |          398 | MachSuite/md/knn            | md.c, md.h             |                |
| transpose          |       399 |          399 | MachSuite/fft/transpose     | fft.c, fft.h           |                |
| stencil3d          |       417 |          417 | MachSuite/stencil/stencil3d | stencil.c, stencil.h   |                |
| ellpack            |       419 |          419 | MachSuite/spmv/ellpack      | spmv.c, spmv.h         |                |
| blocked            |       420 |          420 | MachSuite/gemm/blocked      | gemm.c, gemm.h         |                |
| viterbi            |       425 |          425 | MachSuite/viterbi/viterbi   | viterbi.c, viterbi.h   |                |
| merge              |       450 |          450 | MachSuite/sort/merge        | sort.c, sort.h         |                |
+--------------------+-----------+--------------+-----------------------------+------------------------+----------------+

How to use the DB4HLS framework

Run the db4hls_config.sh script. It will create a virtual environment and install all the python modules required. Activate the virtual environment created with the following instruction:

source venv/bin/activate

Source the VivadoHLS script settings64.sh in order to run VivadoHLS from the DB4HLS folder. Example:

source <path_of_your_vivado_version>/settings64.sh

On my machine is:

source /local/tools/Xilinx/Vivado/2018.2/settings64.sh

NOTE: The venv activation and source of VivadoHLS script need to be re-run after each time you have closed your terminal.

Change the main.py python script according to your preferences and execute it in order to concurrently run an exhaustive exploration of the configuration space defined with the configuration space descriptor files. Please see the content of main.py for an example of small exhaustive DSE exploration.

NOTE: The size of the design spaces grows exponentially with the number of knobs and the number of directive values considered. Therefore the exploration may generate a large number of designs and require a significant amount of time and resources.

Folder structure

All the performed synthesis are generated in the ./syn/ folder. At the end of the exploration, the synthesis folders generated by VivadoHLS are compressed and saved in the ./syn_zip/ folder. Only the report file and the .tcl scrips are saved in order to reduce the amount of memory occupied by the exploration. The original folders are removed from ./syn/, and only the log file of the synthesis process and the list of synthesized design is available in ./syn/. Similarly, the ./tcl_scripts/ is used to temporarily store the .tcl and .dir files automatically generated by the framework.