AVSL Compiler

A compiler for A Very Simple Language

This compiler compile AVSL code to MIPS Assembly Language. The code generated in file a.out by default, you can run the generated code by using Mars, a MIPS simulator. The compiler use Jflex for generating lexer/scanner and CUP for generating parser.

First download jflex and CUP and follow their install instructions. Then generate lexer, parser and compile all java files together. Read Makefile for more details.

To run a test case use this command:

  java -cp java-cup-11b-runtime.jar:. genMain your_test_case

Notes: If you are using Windows, make sure change : to ; in the Makefile and the command to run test cases.

AVSL grammar

You must code AVSL follow a grammar listed below, otherwise the compiler will crash, it doesn't have any error handlers. The grammar contains just basic rules.

ID → letter (letter | digit)*
NUM → digit+
letter → [a-z] | [A-Z]
digit → [0-9]

Program → Block
Expr → ID | NUM | ‘(’ Expr ‘)’
Expr → Unop Expr
Unop → ‘-’ | '+' | '~'
Expr → Expr Binop Expr
Binop → ‘+’ | ‘-’ | ‘*’ | ‘/’ | ‘%’
Stmt → ID ‘=’ Expr ‘;’
Stmt → read ID ‘;’
Stmt → write Expr ‘;’
Stmt → if Expr then Stmt
Stmt → while Expr do Stmt
Stmt → Block
Block → begin Stmts end
Stmts → Stmt | Stmt Stmts