The Elements of Computing Systems, 2ed

%import common.WS
%import common.CPP_COMMENT
%import common.INT
%import common.WORD
 
%ignore WS
%ignore CPP_COMMENT
 
start: (LABEL | ainstr | cinstr)*
 
LABEL: "(" WORD ")"
 
ainstr: "@" SYMBOL
 
SYMBOL: WORD
      | INT
      | "R" "0".."15"
      | "SP"
      | "LCL"
      | "ARG"
      | "THIS"
      | "THAT"
      | "KBD"
      | "SCREEN"
 
cinstr: (DEST "=")? COMP (";" JUMP)?

%import common.WS
%import common.CPP_COMMENT
%import common.INT
%import common.SIGNED_INT
 
%ignore WS
%ignore CPP_COMMENT
 
start: (stackop | arithop)*
 
stackop: (PUSH|POP) SEGMENT INDEX
 
PUSH: "push"
POP: "pop"
 
arithop: ADD
       | SUB
       | NEG
       | EQ
       | GT
       | LT
       | AND
       | OR
       | NOT
 
ADD: "add"
SUB: "sub"
NEG: "neg"
EQ: "eq"
GT: "gt"
LT: "lt"
AND: "and"
OR: "or"
NOT: "not"
 
SEGMENT: "argument"
       | "local"
       | "static"
       | "constant"
       | "this"
       | "that"
       | "pointer"
       | "temp"
 
INDEX: INT