https://github.com/johnwickerson/memalloy
Memory consistency modelling using Alloy
https://github.com/johnwickerson/memalloy
armv7 c11 compiler-design constraint-solver memory-model model-checking nvidia-gpus opencl powerpc x86
Last synced: 4 months ago
JSON representation
Memory consistency modelling using Alloy
- Host: GitHub
- URL: https://github.com/johnwickerson/memalloy
- Owner: johnwickerson
- License: mit
- Created: 2016-07-20T17:23:40.000Z (about 9 years ago)
- Default Branch: master
- Last Pushed: 2020-12-16T15:23:11.000Z (almost 5 years ago)
- Last Synced: 2024-10-11T21:52:41.434Z (12 months ago)
- Topics: armv7, c11, compiler-design, constraint-solver, memory-model, model-checking, nvidia-gpus, opencl, powerpc, x86
- Language: OCaml
- Homepage: http://johnwickerson.github.io/memalloy
- Size: 4.99 MB
- Stars: 28
- Watchers: 7
- Forks: 6
- Open Issues: 10
-
Metadata Files:
- Readme: README.md
- License: LICENSE.txt
Awesome Lists containing this project
README
| Licence | Master branch | Dev branch |
|---------|---------------|------------|
| [](https://opensource.org/licenses/MIT) | [](https://travis-ci.org/johnwickerson/memalloy) | [](https://travis-ci.org/johnwickerson/memalloy) |
# System requirements
- OCaml 4.07.0 or later (tested with 4.07.0)
- OPAM packages `xml-light`, `ocamlfind`, and `ocamlbuild` (hint: `opam install `)
- Python 2.7
- Java runtime version 8 (tested with [Java SE Development Kit 8u181](http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html)).
- Graphviz (hint: `brew install graphviz`)
- Apache Ant, for building Alloy (hint: `brew install ant`)
# Quick start
1. Modify `configure.sh` to suit your OS.
2. Run `source configure.sh`.
3. Run `make install`. HTML documentation can now be browsed at
`doc/index.html`.
4. Run `make quicktest`. After a few minutes you should find some
pictures of distinguishing executions in the `png` directory.
# Converting .cat models to Alloy (.als) format
- Each `.cat` file must begin with a description of the architecture
being modelled. This must be one of: `"BASIC"`, `"C"`, `"HW"`,
`"X86"`, `"PPC"`, `"ARM7"`, `"ARM8"`, `"PTX"`, `"OpenCL"`, or `"OCaml"`.
- A reasonable fragment of the `.cat` language is supported.
- You can define sets and relations via `let x = e`. Names of sets
must begin with an uppercase letter, and names of relations must
begin with a lowercase letter.
- You can define functions via `let f(r1,...,rn) = e`. The name of
the function must begin with an uppercase letter if the function
returns a set, and must begin with a lowercase letter if the
function returns a relation. Functions cannot return functions.
Set-valued parameters must have a name beginning with an
uppercase letter, and relation-valued parameters must begin with
a lowercase letter. Parameters cannot be functions themselves.
- You can define relations (but not sets) recursively via `let x1
= e1 and ... and xn = en`, and these are unrolled a fixed number
of times when translating into Alloy (since Alloy only checks up
to a finite bound anyway). The number of unrollings is set by
the `-u` flag, which defaults to 3.
- You can define a consistency axiom of the model called `name`
via `acyclic|irreflexive|empty e as name`. You can define a
'definedness' axiom (i.e., one that must hold of every
consistent execution or else the whole program is undefined) by
prepending the statement above with `undefined_unless`, and you
can define a 'deadness' axiom (i.e., one that must hold of an
inconsistent execution in order to guarantee that the resultant
litmus test has no other passing executions) by prepending the
statement above with `deadness_requires` instead.
- You can include the definitions and axioms of the `submodel.cat`
file via `include submodel.cat`.
- There are a few syntactic restrictions on `.cat` files.
- The variable `int`, built into Herd, clashes with a keyword in
Alloy, so is not allowed. You can use `thd` instead.
- The variable `X`, built into Herd, clashes with another variable
in Alloy, so is not allowed. You can use `domain(atom) |
range(atom)` instead.
- The variables `L` and `A` are used in Herd for 'release' and
'acquire' accesses in the Arm8 architecture, but these clash
with the variables for 'local' accesses in OpenCL and 'atomic'
accesses in C and OpenCL, respectively. Alloy does not allow
variables to be re-used in this way, so you must use `SCREL` and
`SCACQ` in the Arm8 architecture instead.