diff options
Diffstat (limited to 'py/parse.c')
| -rw-r--r-- | py/parse.c | 80 |
1 files changed, 72 insertions, 8 deletions
diff --git a/py/parse.c b/py/parse.c index 397d46d9f0..dc360e40ce 100644 --- a/py/parse.c +++ b/py/parse.c @@ -227,11 +227,14 @@ STATIC void pop_rule(parser_t *parser, const rule_t **rule, size_t *arg_i, size_ *src_line = parser->rule_stack[parser->rule_stack_top].src_line; } -mp_parse_node_t mp_parse_node_new_leaf(size_t kind, mp_int_t arg) { - if (kind == MP_PARSE_NODE_SMALL_INT) { - return (mp_parse_node_t)(kind | (arg << 1)); - } - return (mp_parse_node_t)(kind | (arg << 4)); +bool mp_parse_node_is_const_false(mp_parse_node_t pn) { + return MP_PARSE_NODE_IS_TOKEN_KIND(pn, MP_TOKEN_KW_FALSE) + || (MP_PARSE_NODE_IS_SMALL_INT(pn) && MP_PARSE_NODE_LEAF_SMALL_INT(pn) == 0); +} + +bool mp_parse_node_is_const_true(mp_parse_node_t pn) { + return MP_PARSE_NODE_IS_TOKEN_KIND(pn, MP_TOKEN_KW_TRUE) + || (MP_PARSE_NODE_IS_SMALL_INT(pn) && MP_PARSE_NODE_LEAF_SMALL_INT(pn) != 0); } bool mp_parse_node_get_int_maybe(mp_parse_node_t pn, mp_obj_t *o) { @@ -408,7 +411,7 @@ STATIC void push_result_token(parser_t *parser, const rule_t *rule) { mp_map_elem_t *elem; if (rule->rule_id == RULE_atom && (elem = mp_map_lookup(&parser->consts, MP_OBJ_NEW_QSTR(id), MP_MAP_LOOKUP)) != NULL) { - pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, MP_OBJ_SMALL_INT_VALUE(elem->value)); + pn = mp_parse_node_new_small_int(MP_OBJ_SMALL_INT_VALUE(elem->value)); } else { pn = mp_parse_node_new_leaf(MP_PARSE_NODE_ID, id); } @@ -419,7 +422,7 @@ STATIC void push_result_token(parser_t *parser, const rule_t *rule) { } else if (lex->tok_kind == MP_TOKEN_INTEGER) { mp_obj_t o = mp_parse_num_integer(lex->vstr.buf, lex->vstr.len, 0, lex); if (MP_OBJ_IS_SMALL_INT(o)) { - pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, MP_OBJ_SMALL_INT_VALUE(o)); + pn = mp_parse_node_new_small_int(MP_OBJ_SMALL_INT_VALUE(o)); } else { pn = make_node_const_object(parser, lex->tok_line, o); } @@ -467,6 +470,63 @@ STATIC MP_DEFINE_CONST_MAP(mp_constants_map, mp_constants_table); STATIC void push_result_rule(parser_t *parser, size_t src_line, const rule_t *rule, size_t num_args); #if MICROPY_COMP_CONST_FOLDING +STATIC bool fold_logical_constants(parser_t *parser, const rule_t *rule, size_t *num_args) { + if (rule->rule_id == RULE_or_test + || rule->rule_id == RULE_and_test) { + // folding for binary logical ops: or and + size_t copy_to = *num_args; + for (size_t i = copy_to; i > 0;) { + mp_parse_node_t pn = peek_result(parser, --i); + parser->result_stack[parser->result_stack_top - copy_to] = pn; + if (i == 0) { + // always need to keep the last value + break; + } + if (rule->rule_id == RULE_or_test) { + if (mp_parse_node_is_const_true(pn)) { + // + break; + } else if (!mp_parse_node_is_const_false(pn)) { + copy_to -= 1; + } + } else { + // RULE_and_test + if (mp_parse_node_is_const_false(pn)) { + break; + } else if (!mp_parse_node_is_const_true(pn)) { + copy_to -= 1; + } + } + } + copy_to -= 1; // copy_to now contains number of args to pop + + // pop and discard all the short-circuited expressions + for (size_t i = 0; i < copy_to; ++i) { + pop_result(parser); + } + *num_args -= copy_to; + + // we did a complete folding if there's only 1 arg left + return *num_args == 1; + + } else if (rule->rule_id == RULE_not_test_2) { + // folding for unary logical op: not + mp_parse_node_t pn = peek_result(parser, 0); + if (mp_parse_node_is_const_false(pn)) { + pn = mp_parse_node_new_leaf(MP_PARSE_NODE_TOKEN, MP_TOKEN_KW_TRUE); + } else if (mp_parse_node_is_const_true(pn)) { + pn = mp_parse_node_new_leaf(MP_PARSE_NODE_TOKEN, MP_TOKEN_KW_FALSE); + } else { + return false; + } + pop_result(parser); + push_result_node(parser, pn); + return true; + } + + return false; +} + STATIC bool fold_constants(parser_t *parser, const rule_t *rule, size_t num_args) { // this code does folding of arbitrary integer expressions, eg 1 + 2 * 3 + 4 // it does not do partial folding, eg 1 + 2 + x -> 3 + x @@ -648,7 +708,7 @@ STATIC bool fold_constants(parser_t *parser, const rule_t *rule, size_t num_args pop_result(parser); } if (MP_OBJ_IS_SMALL_INT(arg0)) { - push_result_node(parser, mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, MP_OBJ_SMALL_INT_VALUE(arg0))); + push_result_node(parser, mp_parse_node_new_small_int(MP_OBJ_SMALL_INT_VALUE(arg0))); } else { // TODO reuse memory for parse node struct? push_result_node(parser, make_node_const_object(parser, 0, arg0)); @@ -674,6 +734,10 @@ STATIC void push_result_rule(parser_t *parser, size_t src_line, const rule_t *ru } #if MICROPY_COMP_CONST_FOLDING + if (fold_logical_constants(parser, rule, &num_args)) { + // we folded this rule so return straight away + return; + } if (fold_constants(parser, rule, num_args)) { // we folded this rule so return straight away return; |