grammmars.txt

L_var

    exp ::= Constant(int)
          | Call(Name('input_int'),[])
          | UnaryOp(USub(), exp)
          | BinOp(exp, Add(), exp)
          | BinOp(exp, Sub(), exp)
          | Name(var)
    stmt ::= Expr(Call(Name('print'), [exp]))
           | Expr(exp) 
           | Assign([Name(var)], exp)
    LVar ::= Module(stmt∗)

L_var^mon

    atm ::= Constant(int)
          | Name(var)
    exp ::= atm
          | Call(Name('input_int'),[])
          | UnaryOp(USub(), atm)
          | BinOp(atm, Add(), atm)
          | BinOp(atm, Sub(), atm)
    stmt ::= Expr(Call(Name('print'), [atm]))
           | Expr(exp) 
           | Assign([Name(var)], exp)
    LVar ::= Module(stmt∗)

X86_Var

    reg ::= 'rsp' | 'rbp' | 'rax' | 'rbx' | 'rcx' | 'rdx' | 'rsi' | 'rdi'
	  | 'r8' | 'r9' | 'r10' | 'r11' | 'r12' | 'r13' | 'r14' | 'r15'
    arg ::= Immediate(int)
	  | Reg(reg)
	  | Deref(reg,int)
	  | Variable(var)
    instr ::= Instr('addq',[arg,arg])
	  | Instr('subq',[arg,arg])
	  | Instr('movq',[arg,arg])
	  | Instr('negq',[arg])
	  | Instr('pushq',[arg])
	  | Instr('popq',[arg])
	  | Callq(label,int)
	  | Instr('retq',[])
	  | Jump(label) 
    x86_Var ::= X86Program(instr∗)


X86_Int

    Remove Variable(var) from arg.

    arg ::= Immediate(int)
	  | Reg(reg)
	  | Deref(reg,int)