Indexed Reverse Polish Notation, an Alternative to AST
a day ago
- #programming-languages
- #indexed-rpn
- #compiler-construction
- Compiler construction knowledge enhances programming skills.
- Indexed RPN is an alternative to Abstract Syntax Trees (ASTs) for representing parsed source code.
- Indexed RPN uses a contiguous array, similar to Reverse Polish Notation (RPN), but with explicit references to sub-expressions via indices.
- Administrative Normal Form (ANF) is used to name intermediate results, making data flow explicit.
- Indexed RPN allows stable references to sub-expressions, facilitating traversal without a stack.
- Introducer nodes like 'Bind' are used to handle scoping and variable declarations.
- BlockStart and BlockEnd nodes manage nested scopes and variable shadowing.
- Jump nodes (BrFalse, Jmp) handle control flow like if-else and loops in a linear sequence.
- A Virtual Machine (VM) can interpret Indexed RPN efficiently, using an Instruction Pointer (ip) and a values array.
- Indexed RPN can be translated to C code, leveraging existing compilers for optimization and code generation.
- Carbon is a real-world language using Indexed RPN, demonstrating its practical benefits.