Tasks provide a framework for running the VTR flow on multiple benchmarks and architectures.

A task specifies a set of benchmark circuits and architectures to be used. By default, tasks execute the run_vtr_flow script for every circuit/architecture combination.

Example Tasks

  • basic_flow: Runs the VTR flow mapping a simple Verilog circuit to an FPGA architecture.
  • timing: Runs the flagship VTR benchmarks on a comprehensive, realistic architecture file.
  • timing_chain: Same as timing but with carry chains.
  • regression_mcnc: Runs VTR on the historical MCNC benchmarks on a legacy architecture file. (Note: This is only useful for comparing to the past, it is not realistic in the modern world)
  • regression_titan\titan_small: Runs a small subset of the Titan benchmarks targetting a simplified Altera Stratix IV (commercial FPGA) architecture capture
  • regression_fpu_hard_block_arch: Custom hard FPU logic block architecture

File Layout

All of VTR’s included tasks are located here:


If users wishes to create their own task, they must do so in this location.

All tasks must contain a configuration file located here:


Fig. 8 illustrates the file layout for a VTR task. Every time the task is run a new run<#> directory is created to store the output files, where <#> is the smallest integer to make the run directory name unique.


Fig. 8 Task file layout.

Creating a New Task

  1. Create the folder $VTR_ROOT/vtr_flow/tasks/<task_name>
  2. Create the folder $VTR_ROOT/vtr_flow/tasks/<task_name>/config
  3. Create and configure the file $VTR_ROOT/vtr_flow/tasks/<task_name>/config/config.txt

Task Configuration File

The task configuration file contains key/value pairs separated by the = character. Comment line are indicted using the # symbol.

Example configuration file:

# Path to directory of circuits to use

# Path to directory of architectures to use

# Add circuits to list to sweep

# Add architectures to list to sweep

# Parse info and how to parse

Required Fields

  • circuit_dir: Directory path of the benchmark circuits.

    Absolute path or relative to $VTR_ROOT/vtr_flow/.

  • arch_dir: Directory path of the architecture XML files.

    Absolute path or relative to $VTR_ROOT/vtr_flow/.

  • circuit_list_add: Name of a benchmark circuit file.

    Use multiple lines to add multiple circuits.

  • arch_list_add: Name of an architecture XML file.

    Use multiple lines to add multiple architectures.

  • parse_file: Parse Configuration file used for parsing and extracting the statistics.

    Absolute path or relative to $VTR_ROOT/vtr_flow/parse/parse_config.

Optional Fields

  • script_path: Script to run for each architecture/circuit combination.

    Absolute path or relative to $VTR_ROOT/vtr_flow/scripts/ or $VTR_ROOT/vtr_flow/tasks/<task_name>/config/)

    Default: run_vtr_flow

    Users can set this option to use their own script instead of the default. The circuit path will be provided as the first argument, and architecture path as the second argument to the user script.

  • script_params: Parameters to be passed to the script.

    This can be used to run partial VTR flows, or to preserve intermediate files.

    Default: none

  • pass_requirements_file: Pass Requirements file.

    Absolute path or relative to $VTR_ROOT/vtr_flow/parse/pass_requirements/ or $VTR_ROOT/vtr_flow/tasks/<task_name>/config/

    Default: none