diff options
Diffstat (limited to 'py/parse.c')
| -rw-r--r-- | py/parse.c | 81 |
1 files changed, 32 insertions, 49 deletions
diff --git a/py/parse.c b/py/parse.c index ce2dcb62cd..3daa5ff83e 100644 --- a/py/parse.c +++ b/py/parse.c @@ -56,8 +56,6 @@ #define RULE_ARG_RULE (0x2000) #define RULE_ARG_OPT_RULE (0x3000) -#define ADD_BLANK_NODE(rule) ((rule->act & RULE_ACT_ADD_BLANK) != 0) - // (un)comment to use rule names; for debugging //#define USE_RULE_NAME (1) @@ -80,10 +78,10 @@ enum { RULE_const_object, // special node for a constant, generic Python object }; -#define ident (RULE_ACT_ALLOW_IDENT) -#define blank (RULE_ACT_ADD_BLANK) #define or(n) (RULE_ACT_OR | n) #define and(n) (RULE_ACT_AND | n) +#define and_ident(n) (RULE_ACT_AND | n | RULE_ACT_ALLOW_IDENT) +#define and_blank(n) (RULE_ACT_AND | n | RULE_ACT_ADD_BLANK) #define one_or_more (RULE_ACT_LIST | 2) #define list (RULE_ACT_LIST | 1) #define list_with_end (RULE_ACT_LIST | 3) @@ -830,25 +828,6 @@ mp_parse_tree_t mp_parse(mp_lexer_t *lex, mp_parse_input_kind_t input_kind) { // matched the rule, so now build the corresponding parse_node - // count number of arguments for the parse_node - i = 0; - bool emit_rule = false; - for (size_t x = 0; x < n; ++x) { - if ((rule->arg[x] & RULE_ARG_KIND_MASK) == RULE_ARG_TOK) { - mp_token_kind_t tok_kind = rule->arg[x] & RULE_ARG_ARG_MASK; - if (tok_kind >= MP_TOKEN_NAME) { - emit_rule = true; - } - if (tok_kind == MP_TOKEN_NAME) { - // only tokens which were names are pushed to stack - i += 1; - } - } else { - // rules are always pushed - i += 1; - } - } - #if !MICROPY_ENABLE_DOC_STRING // this code discards lonely statements, such as doc strings if (input_kind != MP_PARSE_SINGLE_INPUT && rule->rule_id == RULE_expr_stmt && peek_result(&parser, 0) == MP_PARSE_NODE_NULL) { @@ -868,35 +847,29 @@ mp_parse_tree_t mp_parse(mp_lexer_t *lex, mp_parse_input_kind_t input_kind) { } #endif - // always emit these rules, even if they have only 1 argument - if (rule->rule_id == RULE_expr_stmt || rule->rule_id == RULE_yield_stmt) { - emit_rule = true; - } - - // if a rule has the RULE_ACT_ALLOW_IDENT bit set then this - // rule should not be emitted if it has only 1 argument - if (rule->act & RULE_ACT_ALLOW_IDENT) { - emit_rule = false; - } - - // always emit these rules, and add an extra blank node at the end (to be used by the compiler to store data) - if (ADD_BLANK_NODE(rule)) { - emit_rule = true; - push_result_node(&parser, MP_PARSE_NODE_NULL); - i += 1; - } - + // count number of arguments for the parse node + i = 0; size_t num_not_nil = 0; - for (size_t x = 0; x < i; ++x) { - if (peek_result(&parser, x) != MP_PARSE_NODE_NULL) { - num_not_nil += 1; + for (size_t x = n; x > 0;) { + --x; + if ((rule->arg[x] & RULE_ARG_KIND_MASK) == RULE_ARG_TOK) { + mp_token_kind_t tok_kind = rule->arg[x] & RULE_ARG_ARG_MASK; + if (tok_kind == MP_TOKEN_NAME) { + // only tokens which were names are pushed to stack + i += 1; + num_not_nil += 1; + } + } else { + // rules are always pushed + if (peek_result(&parser, i) != MP_PARSE_NODE_NULL) { + num_not_nil += 1; + } + i += 1; } } - if (emit_rule || num_not_nil != 1) { - // need to add rule when num_not_nil==0 for, eg, atom_paren, testlist_comp_3b - push_result_rule(&parser, rule_src_line, rule, i); - } else { - // single result, leave it on stack + + if (num_not_nil == 1 && (rule->act & RULE_ACT_ALLOW_IDENT)) { + // this rule has only 1 argument and should not be emitted mp_parse_node_t pn = MP_PARSE_NODE_NULL; for (size_t x = 0; x < i; ++x) { mp_parse_node_t pn2 = pop_result(&parser); @@ -905,6 +878,16 @@ mp_parse_tree_t mp_parse(mp_lexer_t *lex, mp_parse_input_kind_t input_kind) { } } push_result_node(&parser, pn); + } else { + // this rule must be emitted + + if (rule->act & RULE_ACT_ADD_BLANK) { + // and add an extra blank node at the end (used by the compiler to store data) + push_result_node(&parser, MP_PARSE_NODE_NULL); + i += 1; + } + + push_result_rule(&parser, rule_src_line, rule, i); } break; } |