2. Quickstart

2.1. Install Python

UbuntuCentOS7

Ubuntu 17.10 and 18.04 by default come with python-3.6.9 which is sufficient for using riscv-isac.

If you are are Ubuntu 16.10 and 17.04 you can directly install python3.6 using the Universe repository

$ sudo apt-get install python3.6
$ pip3 install --upgrade pip

If you are using Ubuntu 14.04 or 16.04 you need to get python3.6 from a Personal Package Archive (PPA)

$ sudo add-apt-repository ppa:deadsnakes/ppa
$ sudo apt-get update
$ sudo apt-get install python3.6 -y
$ pip3 install --upgrade pip

You should now have 2 binaries: python3 and pip3 available in your $PATH. You can check the versions as below

$ python3 --version
Python 3.6.9
$ pip3 --version
pip 20.1 from <user-path>.local/lib/python3.6/site-packages/pip (python 3.6)

2.1.1. Using Virtualenv for Python

Many a times users face issues in installing and managing multiple python versions. This is actually a major issue as many gui elements in Linux use the default python versions, in which case installing python3.6 using the above methods might break other software. We thus advise the use of pyenv to install python3.6.

For Ubuntu and CentosOS, please follow the steps here: https://github.com/pyenv/pyenv#basic-github-checkout

RHEL users can find more detailed guides for virtual-env here: https://developers.redhat.com/blog/2018/08/13/install-python3-rhel/#create-env

Once you have pyenv installed do the following to install python 3.6.0:

$ pyenv install 3.6.0
$ pip3 install --upgrade pip
$ pyenv shell 3.6.0

You can check the version in the same shell:

$ python --version
Python 3.6.0
$ pip --version
pip 20.1 from <user-path>.local/lib/python3.6/site-packages/pip (python 3.6)

2.2. Install RISC-V ISAC

via gitvia pipfor Dev

$ python3 -m pip3 install git+https://github.com/riscv/riscv-isac.git

This is the preferred method to install RISC-V ISA Coverage, as it will always install the most recent stable release.

If you don’t have pip installed, this Python installation guide can guide you through the process.

2.3. Test RISC-V ISAC

Once you have RISCV-ISAC installed, executing riscv_isac --help should print the following on the terminal.

Options:
   --version                       Show the version and exit.
   -v, --verbose [info|error|debug]
                                   Set verbose level
   --help                          Show this message and exit.

Commands:
  coverage   Run Coverage analysis on tracefile.
  merge      Merge given coverage files.
  normalize  Normalize the cgf.

RISCV-ISAC has three commands : coverage, merge and normalize which are described below. Help text for each command can be accessed by executing riscv_isac <command> --help

CoverageMergeNormalize

Usage: riscv_isac coverage [OPTIONS]

  Run Coverage analysis on tracefile.

Options:
  -e, --elf PATH                  ELF file
  -t, --trace-file PATH           Instruction trace file to be analyzed
                                  [required]

  -c, --cgf-file PATH             Coverage Group File(s). Multiple allowed.
                                  [required]

  -d, --detailed                  Select detailed mode of  coverage printing
  --parser-name NAME              Parser plugin name. Parsers shipped with
                                  ISAC - [c_sail, spike]  [default: c_sail]

  --decoder-name NAME             Decoder plugin name. Decoders shipped with
                                  ISAC - [internaldecoder]  [default:
                                  internaldecoder]

  --parser-path PATH              Parser file path
  --decoder-path PATH             Decoder file path
  -o, --output-file PATH          Coverage Group File
  --test-label LABEL_START LABEL_END
                                  Pair of labels denoting start and end points
                                  of the test region(s). Multiple allowed.

  --sig-label LABEL_START LABEL_END
                                  Pair of labels denoting start and end points
                                  of the signature region(s). Multiple
                                  allowed.

  --dump PATH                     Dump Normalized Coverage Group File
  -l, --cov-label COVERAGE LABEL  Coverage labels to consider for this run.
  -x, --xlen [32|64]              XLEN value for the ISA.
  --help                          Show this message and exit.

2.4. Running RISC-V ISAC

There are 3 different operations which can be performed by RISC-V ISAC namely,

1. coverage - Calculate the coverage of a test using the given log and cgf file(s).

2. merge - Merge different coverage reports to produce a single report with all statistics.

3. normalize - Dump a cgf file without any yaml anchors and abstract functions. The output file will contain the elaborated coverpoints as specified by the input cgf file(s).

The CGF file(s) used in these examples can be obtained from here.

Example usage of each of the commands are given below:

CoverageMergeNormalize

RISC-V ISAC is shipped with the following standard plugins.

1. Parser Plugins:

   • SAIL C Model c_sail: Parser for execution logs from the C model generated by SAIL.

   • SPIKE spike: Parser for execution logs from riscv-isa-sim.

2. Decoder Plugins:

   • Native Python Decoder internaldecoder: A decoder for the RISC-V isa written in python.

The c_sail and the internaldecoder plugins are used by default. To use custom plugins with RISC-V ISAC refer here.

For a log file generated after running a test from the Architecture Test Suite on the SAIL C Model, the following command can be used to compute coverage for the test:

riscv_isac --verbose info coverage -d -t add-01.log --parser-name c_sail --decoder-name internaldecoder -o coverage.rpt --sig-label begin_signature end_signature --test-label rvtest_code_begin rvtest_code_end -e add-01.elf -c dataset.cgf -c rv32i.cgf -x 32 -l add

Note

The command assumes that the cgf files are in the same directory. Modify paths to the -c argument accordingly.

Note

The command assumes that the coverage is calculated for the add test. Modify paths to the -e and -t arguments accordingly. The label should also be changed based on requirements.

Note

To use the spike parser use --parser-name spike.

Warning

Coverage reported by ISAC is based on the instructions reported in the trace file. Hence it is imperative that all instructions are reported in the trace file. Currently the coverage reporting using the SPIKE model is inaccurate because instructions which trap are not reported in the trace file. It is advisable to use the SAIL model for accurate coverage reporting.