dfava / mmgo

Operational Semantics of a Weak Memory Model with Channel Synchronization

mmGo

Operational Semantics of a Weak Memory Model with Channel Synchronization

This is an implementation, in the K-framework, of a weak memory model for a calculus inspired by the Go programming language. The model has buffered channel communication as the sole synchronization primitive.

Details of the memory model can be found in the following technical report.

Install

It uses the K executable semantics framework. Follow installation instructions from K's github page. It requires the Java Development Kit, Apache Maven.

(Note that there currently exist two versions of K, one called RV-K and another UIUC-K. Though the mmGo semantics here works with both, the link above points to RV-K. RV-K is recommended; UIUC-K is in the process of being deprecated.)

Running

Once K is installed, it is easy to run an example by following the steps:

1. kompile

cd src/k/mmgo-dw
kompile mmgo.k

2. krun

From src/k/mmgo-dw:

krun ../../mmgo/example/example.mmgo

This runs the delayed-writes version of the memory model (mmgo-dw). There is also a sequentially consistent version of the memory model, which you can run by replacing mmgo-dw with mmgo-sc.

Development

These step are only required if you want to further develop mmgo.

It assumes you have Python3 installed and assumes that you checked out the mmgo repository at ~/mmgo.

1. Set-up for running regression tests

It is recommended to:

• add $HOME/mmgo/bin and $HOME/mmgo/lib to your PYTHONPATH; and
• add $HOME/mmgo/bin to PATH.

One way to do this, for example, is by adding the following lines to a .bash_profile:

export PYTHONPATH=$PYTHONPATH:$HOME/mmgo/bin:$HOME/mmgo/lib
export PATH=$PATH:$HOME/mmgo/bin

Install dependencies

• pyparsing, which can be installed with pip:
  pip3 install pyparsing

The regression scripts also use the Python unittest library, which should be installed by default.

2. Running regression tests

Here is an example of running a single test, in this case var_write.mmgo, using the delayed-writes version of the memory model called mmmgo-dw

cd src/mmgo/tests
mmgo-run.py mmgo-dw var_write.mmgo

Here is an example of running all tests using the sequentially consistent version of the memory model, called mmgo-sc

cd src/mmgo/tests
mmgo-run.py mmgo-sc *.mmgo

Updates

Date	Comment
Feb 9, 2018	mmGo semantics works on RV-K as well as UIUC-K
Jan 23, 2018	Updated technical report with proof of SC-DRF guarantee
Nov 29, 2017	Update to test framework Removed dependency on simplexquery library