Bytecode and VM Integration

[Roger-luo]

Summary

Reintroduce virtual machine interfaces and orchestration capabilities in the ppvm project to support mix-mode propagation (DFS + BFS) and make the bytecode more easily integrable with downstream users.

Background

• Previous implementation details can be referenced from the pao project.
• Current components related to virtual hardware are being refactored in stellarscope/vihaco by Kai-Hsin Wu (expected to be ready in about a week).

Motivation

• Enable support for both Depth-First Search (DFS) and Breadth-First Search (BFS) propagation modes in the VM layer.
• Facilitate broader bytecode compatibility and easier integration for downstream users and frameworks.
• Unify present and future virtual hardware abstractions with orchestration features for more flexible program execution.

Action Items

• Review previous virtual machine and orchestration logic from pao.
• Evaluate and integrate refactored components from stellarscope/vihaco once available.
• Redesign/expose an interface to seamlessly support both DFS and BFS propagation.
• Document bytecode integration guidelines for external users.
• Add tests for mixed-mode propagation and downstream interop.

/cc @kaihsin (please update this thread when refactor PR is ready)

[david-pl]

@Roger-luo could you provide some more details on how we should support the combination of BFS and DFS? What exactly do you mean by the "mixed-mode propagation"?