Implementation Plan: Zero-Copy Vox Codegen

Implementation Plan: Zero-Copy Vox Codegen

Overview

This plan outlines the technical steps to transition Vox from a “Clone-Heavy” Rust backend to a “Zero-Copy” systems-native backend. This is Phase 1 of the Native Code Emission strategy.

1. Enrich HIR with Type Information

The primary blocker for smart codegen is that HIR nodes do not know their types. We store resolved types in a centralized map within the HirModule.

• Extend HirModule in crates/vox-compiler/src/hir/nodes/decl.rs:
  • Add pub inferred_types: HashMap<Span, HirType> field.
• Update Checker in crates/vox-compiler/src/typeck/checker/mod.rs:
  • Add inferred_types map to the Checker struct.
  • Write resolved types to the map during check_expr in expr.rs.
• Refactor typecheck_hir:
  • Pass the module’s inferred_types to the checker.
  • Resolve borrow-checker conflicts by temporarily taking ownership of the map during checking.

2. Implement Smart Ownership Tracking in Codegen

Update vox-codegen to use type information to avoid unnecessary .clone() calls.

• Refactor Codegen Layers:
  • Propagate inferred_types through emit_lib, emit_fn, emit_stmt, and emit_expr_with.
  • Update all call sites in stmt_expr.rs, stmt_expr_tail.rs, workflow.rs, and http.rs.
• Optimize Identifiers:
  • Check for Copy types: If the inferred type is a primitive (int, bool, float, char, dec), omit .clone().
• Advanced String Optimization:
  • Escape Analysis: If an identifier is passed to a function that takes a reference (e.g., str -> &str), emit &n or n.as_str() instead of n.clone().
  • Last-Use Detection: If the compiler can prove an identifier is used for the last time in a scope, “move” it instead of cloning.

3. Native UI Prototype (Visus)

Establish a pathway for non-React UI emission.

• Create crates/vox-native-gui:
  • Define a NativeRenderer trait.
  • Implement a Slint or egui backend that maps HirJsxElement to native widgets.
• Update vox-codegen:
  • Add --target=native flag to the CLI.
  • Branch the Component lowering path: HIR → WebIR (for React) vs HIR → NativeIR (for systems UI).

4. WASM Logic Offloading

Enable high-performance logic offloading to WASM for @pure functions.

• Identify @pure performance-critical functions:
  • Use the @intrinsic decorator (proposed in research) to flag these functions.
• Lower to WASM:
  • Use vox-wasm-engine to compile these functions to .wasm blobs.
  • Emit Rust glue code in the server that calls into the WASM module instead of executing interpreted logic.

Verification

• Benchmark: Run the vox-bench suite before and after the “Zero-Copy” changes.
• Regression: Ensure cargo test --workspace passes, specifically checking vox-codegen tests that previously relied on .clone() behavior.

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Last Updated: 2026-05-12 Status: In Progress