SNL Compiler

SNL Compiler frontend implemented in rust and c(with ffi).

Structure

• snl-lexer: Lexer written in Rust
  • Tokenize
  • Line & Column
  • Comment
• snl-rdp: Recursive descent parser written in Rust
• snl-ll1: LL(1) parser written in Rust.
• snl-semantic: Semantic Analysis part written in Rust
  • Construct symbol table
    • Type
    • Variable
    • Procedure
  • Semantic errors
    • Duplicated identifier
    • Undefined identifier
    • Undefined type
    • Uncompatable type
    • Invalid variable represent
    • Invalid array definition
    • Array index outbound
    • Unexpected array index
    • Invalid field index type
    • Undefined record field
    • Assign type mismatch
    • Invalid assignee
    • Call parameter type mismatch
    • Call parameter count mismatch
    • Invalid bool expression
    • Invalid read type
    • Invalid write type
• snl-utils: Some common parts
• snlc: Simple representation program, uses all the librarys above

Grammar information

• BNF: https://github.com/Yesterday17/SNLCompiler/blob/master/grammar/snl.bnf
• BNF(LL(1)): https://github.com/Yesterday17/SNLCompiler/blob/master/grammar/snl_ll1.bnf
• Format used to generate predict table: https://github.com/Yesterday17/SNLCompiler/blob/6587ea8046c9727f1895a408f513d3072e5f46d0/grammar/snl_ll1

Tools used

• Predict table generation: http://jsmachines.sourceforge.net/machines/ll1.html
• AST(JSON) to SVG: https://vanya.jp.net/vtree/