diff options
Diffstat (limited to 'src/parser.y')
| -rw-r--r-- | src/parser.y | 170 |
1 files changed, 88 insertions, 82 deletions
diff --git a/src/parser.y b/src/parser.y index cb3544e..f03e54f 100644 --- a/src/parser.y +++ b/src/parser.y @@ -17,93 +17,99 @@ void yyerror(const char *s) { %union { int num; char *id; - int op; struct ASTNode *node; } -%start program - -%token <id> TOKEN_IDENTIFIER -%token <num> TOKEN_NUMERAL -%token TOKEN_ASSIGN -%token TOKEN_LEFT_PARENTHESIS TOKEN_RIGHT_PARENTHESIS -%token TOKEN_SEMICOLON -%token TOKEN_SKIP -%token TOKEN_IF TOKEN_THEN TOKEN_ELSE TOKEN_END TOKEN_WHILE TOKEN_DO TOKEN_VAR TOKEN_IN -%token TOKEN_PLUS TOKEN_MINUS TOKEN_MULTIPLY -%token TOKEN_NOT TOKEN_OR TOKEN_AND -%token TOKEN_EQUALS TOKEN_NOT_EQUALS TOKEN_LESS_THAN TOKEN_LESS_EQUAL TOKEN_GREATER_THAN TOKEN_GREATER_EQUAL - -%type <node> program statement variable arithmetic_expression boolean_expression -%type <op> arithmetic_operation boolean_operation relational_operation - +%start prog + +%token <num> T_NUM +%token <id> T_ID +%token T_EQ T_NE T_LT T_LE T_GT T_GE +%token T_TRUE T_FALSE +%left T_OR +%left T_AND +%token T_NOT +%left T_PLUS T_MINUS +%left T_STAR +%right T_UMINUS +%token T_END T_IF T_THEN T_ELSE T_WHILE T_DO T_VAR T_IN +%token T_SKIP +%token T_ASSIGN +%token T_LPAREN T_RPAREN +%token T_SEM + +%type <node> prog stm var aexp bexp %% - -program : statement - { ast_root = $1; } - ; - -statement : TOKEN_SKIP - { $$ = ast_skip(); } - | variable TOKEN_ASSIGN arithmetic_expression - { $$ = ast_assign($1, $3); } - | TOKEN_LEFT_PARENTHESIS statement TOKEN_SEMICOLON statement TOKEN_RIGHT_PARENTHESIS - { $$ = ast_seq($2, $4); } - | TOKEN_IF boolean_expression TOKEN_THEN statement TOKEN_ELSE statement TOKEN_END - { $$ = ast_if($2, $4, $6); } - | TOKEN_WHILE boolean_expression TOKEN_DO statement TOKEN_END - { $$ = ast_while($2, $4); } - | TOKEN_VAR variable TOKEN_ASSIGN arithmetic_expression TOKEN_IN statement TOKEN_END - { $$ = ast_let($2, $4, $6); } - ; - -variable : TOKEN_IDENTIFIER - { $$ = ast_var($1); } - ; - -arithmetic_expression : TOKEN_LEFT_PARENTHESIS arithmetic_expression arithmetic_operation arithmetic_expression TOKEN_RIGHT_PARENTHESIS - { $$ = ast_aop($3, $2, $4); } - | variable - { $$ = $1; } - | TOKEN_NUMERAL - { $$ = ast_int($1); } - ; - -arithmetic_operation : TOKEN_PLUS - { $$ = AOP_ADD; } - | TOKEN_MINUS - { $$ = AOP_SUB; } - | TOKEN_MULTIPLY - { $$ = AOP_MUL; } - ; - -boolean_expression : TOKEN_LEFT_PARENTHESIS boolean_expression boolean_operation boolean_expression TOKEN_RIGHT_PARENTHESIS - { $$ = ast_bop($3, $2, $4); } - | TOKEN_NOT boolean_expression - { $$ = ast_not($2); } - | arithmetic_expression relational_operation arithmetic_expression - { $$ = ast_rop($2, $1, $3); } - ; - -boolean_operation : TOKEN_OR - { $$ = BOP_OR; } - | TOKEN_AND - { $$ = BOP_AND; } - ; -relational_operation : TOKEN_EQUALS - { $$ = ROP_EQ; } - | TOKEN_NOT_EQUALS - { $$ = ROP_NE; } - | TOKEN_LESS_THAN - { $$ = ROP_LT; } - | TOKEN_LESS_EQUAL - { $$ = ROP_LE; } - | TOKEN_GREATER_THAN - { $$ = ROP_GT; } - | TOKEN_GREATER_EQUAL - { $$ = ROP_GE; } - ; +prog : stm + { ast_root = $1; } + ; + +stm : T_SKIP + { $$ = ast_skip(); } + | var T_ASSIGN aexp + { $$ = ast_assign($1, $3); } + | T_LPAREN stm T_SEM stm T_RPAREN + { $$ = ast_seq($2, $4); } + | stm T_SEM stm + { $$ = ast_seq($1, $3); } + | stm T_SEM + { $$ = $1; } + | T_IF bexp T_THEN stm T_ELSE stm T_END + { $$ = ast_if($2, $4, $6); } + | T_IF bexp T_THEN stm T_END + { $$ = ast_if($2, $4, ast_skip()); } + | T_WHILE bexp T_DO stm T_END + { $$ = ast_while($2, $4); } + | T_VAR var T_ASSIGN aexp T_IN stm T_END + { $$ = ast_let($2, $4, $6); } + ; + +var : T_ID + { $$ = ast_var($1); } + ; + +aexp : aexp T_PLUS aexp + { $$ = ast_aop(AOP_ADD, $1, $3); } + | aexp T_MINUS aexp + { $$ = ast_aop(AOP_SUB, $1, $3); } + | aexp T_STAR aexp + { $$ = ast_aop(AOP_MUL, $1, $3); } + | T_MINUS aexp %prec T_UMINUS + { $$ = ast_aop(AOP_SUB, ast_int(0), $2); } + | T_LPAREN aexp T_RPAREN + { $$ = $2; } + | var + { $$ = $1; } + | T_NUM + { $$ = ast_int($1); } + ; + +bexp : bexp T_OR bexp + { $$ = ast_bop(BOP_OR, $1, $3); } + | bexp T_AND bexp + { $$ = ast_bop(BOP_AND, $1, $3); } + | T_NOT bexp + { $$ = ast_not($2); } + | aexp T_EQ aexp + { $$ = ast_rop(ROP_EQ, $1, $3); } + | aexp T_NE aexp + { $$ = ast_rop(ROP_NE, $1, $3); } + | aexp T_LE aexp + { $$ = ast_rop(ROP_LE, $1, $3); } + | aexp T_LT aexp + { $$ = ast_rop(ROP_LT, $1, $3); } + | aexp T_GE aexp + { $$ = ast_rop(ROP_GE, $1, $3); } + | aexp T_GT aexp + { $$ = ast_rop(ROP_GT, $1, $3); } + | T_LPAREN bexp T_RPAREN + { $$ = $2; } + | T_TRUE + { $$ = ast_rop(ROP_EQ, ast_int(1), ast_int(1)); } + | T_FALSE + { $$ = ast_rop(ROP_EQ, ast_int(0), ast_int(1)); } + ; %% |