grammar.bnf

statement ::= assignment | builtin

builtin ::= "store!" | "load!"

assignment ::= lefthand assignment_operator expression

assignment_operator ::= "=" |
                          "&=" |
                          "|=" |
                          "^=" |
                          "+=" |
                          "-=" |
                          "*="

expression ::= expression 'and' expression |
               expression 'or' expression |
               expression 'in' list |
               expression '?' expression ':' expression |
               expression '<' expression '<' expression |
               expression '>' expression '>' expression |
               expression '+' expression |
               expression '-' expression |
               expression '*' expression |
               expression '&' expression |
               expression '|' expression |
               expression '^' expression |
               expression '<' expression |
               expression '>' expression |
               expression '==' expression |
               expression '<<' expression |
               expression '>>>' expression |
               expression '>>' expression |
               '-' expression |
               '(' expression ')' |
               lefthand |
               constant |
               immediate

list ::= '[' element_list ']'
element_list ::= element_list, list_element |
                 list_element
list_element ::= lefthand | constant | immediate

lefthand ::= variable_name | "$" register_name


register_name ::= 'id_hi' |
                  'id_low' |
                  'id' |
                  'address_hi' |
                  'address_low' |
                  'address' |
                  'data' |
                  'mask'

variable ::= IDENTIFIER_VARIABLE
constant ::= '$constant[' INTEGER ']'
immediate ::= INTEGER | BINARY | HEX