HPR Library

The HPR L/S library is all based around the HPR VM defined in abstract.hdr.

The library is written in F# (this runs just fine on mono/linux).

A VM contains variable declarations, executable code, temporal logic assertions and child machines.

A system is a list of VMs where each may be the root of a tree of VMs.

Variables are signed and unsiged integers of various precisions and 1-D arrays of such integers. Floating point is being added. A small amount of string handling is also provided.

All variable are static (no dynamic storage) and must be unique in a single namespace that spans the system.

The executable code of a VM has several basic forms:

• DIC - Directly-indexed array: Imperative program (assign/conditional branch/builtin call) stored in an array indexed by a PC.
• ASM - Assembler for a local family of microprocessors
• RTL - Register transfer-level code - a set of parallel assignments to be executed on an event.
• CMD - Abstract syntax tree of a behavioural program (for/while/break/continue/assign/if etc) or single assigment statement.
• FSM - Finite state machine form - like RTL but collated into disjoint sets

The executable code may be clocked or nonclocked.

Fragments may be put in serial or parallel using the SP_par and SP_seq combinators. There are two variants of SP_par, for lockstep and asynchronous composition.