AST

The AST is defined in ast.zig and represents the parsed structure of a translation unit.

What belongs in the AST

• Expression structure (binary ops, unary ops, calls, literals, identifiers)
• Statement structure (if/while/for/return/block)
• Declarations (vars, funcs, types)
• Type syntax (pointers/arrays/functions/etc.)

What should NOT belong in the AST

• target-specific details (RV32 registers, stack layout)
• fully-lowered control flow (that’s IR’s job)
• ad-hoc semantic flags if they can live in a separate analysis table

Recommended invariants

Document invariants here as you discover them. Examples:

• “Every break/continue must appear inside a loop”
• “Every identifier node must resolve to exactly one symbol post-sema”
• “Every function body ends with an explicit return in IR”