vm-dev

Bytecode design defines the instruction set and operand stack behavior for cross-platform execution. Start by specifying opcodes in BytecodeDefinition, then implement corresponding instruction handlers. This approach simplifies runtime behavior and enables portable execution across different environments.

A stack-based VM manages stack frames, local variables, and call/return operations to simplify runtime execution. Define your instruction set, implement stack frame management, and wire instruction handlers to bytecode operations. Use mvn test to validate each new instruction as you add it.

Garbage collection strategies like mark-sweep and reference counting reduce memory leaks in VM execution. Implement object layout specifications, track reachable objects during marking phases, and reclaim unreachable memory. This prevents memory bloat during long-running bytecode execution.

Stack-based VMs are simpler to implement and manage stack frames naturally, while register-based VMs offer performance optimization. This Skill covers both approaches; choose stack-based for clarity and register-based when you need efficiency gains after profiling bytecode execution.

Add new instructions to BytecodeDefinition, implement their handler logic, then run mvn test to validate behavior. This workflow integrates testing into the development cycle, catching instruction errors early and ensuring memory safety during execution.