Behavioural Expression using Threads

We express the algorithm and steps to be performed as an executable program

• using an imperative program (containing loops and assigments), or
• a functional program (where control flow is less-explicit).

Either way, the tool chain may:

• re-order the operations while preserving semantics, and/or
• re-encode the state and modify memory layouts.

Examples:

• Synopsys Behavioural Compiler for RTL (now defunct),
• Handel-C,
• Liquid Metal (Lime Language, IBM), Kiwi (Univ Cambridge/Microsoft),
• C-to-Gates : C-To-Verilog, SystemCrafter, LegUp, Catapult,
• Using Join Patterns or other parallel process algebra (C-omega).

The Kiwi, C-omega and Handel-C approaches are unusual: start with parallel programs and exploit the scheduler non-determinacy to allow variations in implementation.