X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/02d12d0de29cd35a6fd2acabc551e0d89b3fa242..4a678af8c6f178b797e42a60d7ee3774afbdc14e:/src/reader.c diff --git a/src/reader.c b/src/reader.c index 0fa162d9..e58b0327 100644 --- a/src/reader.c +++ b/src/reader.c @@ -22,6 +22,7 @@ #include #include "system.h" +#include #include @@ -31,10 +32,11 @@ #include "getargs.h" #include "gram.h" #include "muscle_tab.h" -#include "output.h" #include "reader.h" #include "symlist.h" #include "symtab.h" +#include "scan-gram.h" +#include "scan-code.h" static void check_and_convert_grammar (void); @@ -66,18 +68,20 @@ grammar_start_symbol_set (symbol *sym, location loc) } -/*----------------------------------------------------------------. -| There are two prologues: one before %union, one after. Augment | -| the current one. | -`----------------------------------------------------------------*/ +/*---------------------------------------------------------------------. +| There are two prologues: one before the first %union and one after. | +| Augment the one specified by POST. | +`---------------------------------------------------------------------*/ void -prologue_augment (const char *prologue, location loc) +prologue_augment (const char *prologue, location loc, bool post) { struct obstack *oout = - !typed ? &pre_prologue_obstack : &post_prologue_obstack; + !post ? &pre_prologue_obstack : &post_prologue_obstack; obstack_fgrow1 (oout, "]b4_syncline(%d, [[", loc.start.line); + /* FIXME: Protection of M4 characters missing here. See + output.c:escaped_output. */ MUSCLE_OBSTACK_SGROW (oout, quotearg_style (c_quoting_style, loc.start.file)); obstack_sgrow (oout, "]])[\n"); @@ -86,14 +90,13 @@ prologue_augment (const char *prologue, location loc) -/*-------------------------------------------------------------------. -| Return the merger index for a merging function named NAME, whose | -| arguments have type TYPE. Records the function, if new, in | -| MERGER_LIST. | -`-------------------------------------------------------------------*/ +/*------------------------------------------------------------------------. +| Return the merger index for a merging function named NAME. Records the | +| function, if new, in MERGER_LIST. | +`------------------------------------------------------------------------*/ static int -get_merge_function (uniqstr name, uniqstr type, location loc) +get_merge_function (uniqstr name) { merger_list *syms; merger_list head; @@ -102,9 +105,6 @@ get_merge_function (uniqstr name, uniqstr type, location loc) if (! glr_parser) return 0; - if (type == NULL) - type = uniqstr_new (""); - head.next = merge_functions; for (syms = &head, n = 1; syms->next; syms = syms->next, n += 1) if (UNIQSTR_EQ (name, syms->next->name)) @@ -113,16 +113,51 @@ get_merge_function (uniqstr name, uniqstr type, location loc) { syms->next = xmalloc (sizeof syms->next[0]); syms->next->name = uniqstr_new (name); - syms->next->type = uniqstr_new (type); + /* After all symbol type declarations have been parsed, packgram invokes + record_merge_function_type to set the type. */ + syms->next->type = NULL; syms->next->next = NULL; merge_functions = head.next; } - else if (!UNIQSTR_EQ (type, syms->next->type)) - warn_at (loc, _("result type clash on merge function %s: <%s> != <%s>"), - name, type, syms->next->type); return n; } +/*-------------------------------------------------------------------------. +| For the existing merging function with index MERGER, record the result | +| type as TYPE as required by the lhs of the rule whose %merge declaration | +| is at DECLARATION_LOC. | +`-------------------------------------------------------------------------*/ + +static void +record_merge_function_type (int merger, uniqstr type, location declaration_loc) +{ + int merger_find; + merger_list *merge_function; + + if (merger <= 0) + return; + + if (type == NULL) + type = uniqstr_new (""); + + merger_find = 1; + for (merge_function = merge_functions; + merge_function != NULL && merger_find != merger; + merge_function = merge_function->next) + merger_find += 1; + assert (merge_function != NULL && merger_find == merger); + if (merge_function->type != NULL && !UNIQSTR_EQ (merge_function->type, type)) + { + warn_at (declaration_loc, + _("result type clash on merge function `%s': <%s> != <%s>"), + merge_function->name, type, merge_function->type); + warn_at (merge_function->type_declaration_location, + _("previous declaration")); + } + merge_function->type = uniqstr_new (type); + merge_function->type_declaration_location = declaration_loc; +} + /*--------------------------------------. | Free all merge-function definitions. | `--------------------------------------*/ @@ -176,7 +211,7 @@ grammar_symbol_append (symbol *sym, location loc) /* The rule currently being defined, and the previous rule. CURRENT_RULE points to the first LHS of the current rule, while PREVIOUS_RULE_END points to the *end* of the previous rule (NULL). */ -symbol_list *current_rule = NULL; +static symbol_list *current_rule = NULL; static symbol_list *previous_rule_end = NULL; @@ -212,17 +247,16 @@ grammar_current_rule_begin (symbol *lhs, location loc) } -/*-----------------------------------------------------------------. -| A symbol is typed if it has a declared %type, or if it is a | -| mid-rule symbol (i.e., the generated LHS replacing a mid-rule | -| action) that was assigned to, as in `exp: { $$ = 1; } { $$ = $1; | -| }'. | -`-----------------------------------------------------------------*/ +/*----------------------------------------------------------------------. +| A symbol should be used if it has a destructor, or if it is a | +| mid-rule symbol (i.e., the generated LHS replacing a mid-rule | +| action) that was assigned to, as in "exp: { $$ = 1; } { $$ = $1; }". | +`----------------------------------------------------------------------*/ static bool -symbol_typed_p (const symbol_list *s) +symbol_should_be_used (symbol_list const *s) { - return (s->sym->type_name + return (s->sym->destructor || (s->midrule && s->midrule->used)); } @@ -261,13 +295,13 @@ grammar_rule_check (const symbol_list *r) _("empty rule for typed nonterminal, and no action")); } - /* Check that typed symbol values are used. */ + /* Check that symbol values that should be used are in fact used. */ { symbol_list const *l = r; int n = 0; for (; l && l->sym; l = l->next, ++n) if (! (l->used - || !symbol_typed_p (l) + || !symbol_should_be_used (l) /* The default action, $$ = $1, `uses' both. */ || (!r->action && (n == 0 || n == 1)))) { @@ -290,7 +324,6 @@ grammar_current_rule_end (location loc) /* Put an empty link in the list to mark the end of this rule */ grammar_symbol_append (NULL, grammar_end->location); current_rule->location = loc; - grammar_rule_check (current_rule); } @@ -301,7 +334,7 @@ grammar_current_rule_end (location loc) | rule. | `-------------------------------------------------------------------*/ -static void +void grammar_midrule_action (void) { /* Since the action was written out with this rule's number, we must @@ -323,10 +356,9 @@ grammar_midrule_action (void) midrule->action = current_rule->action; midrule->action_location = dummy_location; current_rule->action = NULL; - /* If $$ was used in the action, the LHS of the enclosing rule was - incorrectly flagged as used. */ - midrule->used = current_rule->used; - current_rule->used = false; + /* The action has not been translated yet, so $$ use hasn't been + detected yet. */ + midrule->used = false; if (previous_rule_end) previous_rule_end->next = midrule; @@ -335,7 +367,6 @@ grammar_midrule_action (void) /* End the dummy's rule. */ midrule->next = symbol_list_new (NULL, dummy_location); - grammar_rule_check (midrule); midrule->next->next = current_rule; previous_rule_end = midrule->next; @@ -344,6 +375,8 @@ grammar_midrule_action (void) the current rule. Bind it to its dedicated rule. */ grammar_current_rule_symbol_append (dummy, dummy_location); grammar_end->midrule = midrule; + midrule->midrule_parent_rule = current_rule; + midrule->midrule_parent_rhs_index = symbol_list_length (current_rule->next); } /* Set the precedence symbol of the current rule to PRECSYM. */ @@ -380,8 +413,8 @@ grammar_current_rule_merge_set (uniqstr name, location loc) warn_at (loc, _("%s affects only GLR parsers"), "%merge"); if (current_rule->merger != 0) complain_at (loc, _("only one %s allowed per rule"), "%merge"); - current_rule->merger = - get_merge_function (name, current_rule->sym->type_name, loc); + current_rule->merger = get_merge_function (name); + current_rule->merger_declaration_location = loc; } /* Attach SYM to the current rule. If needed, move the previous @@ -395,14 +428,15 @@ grammar_current_rule_symbol_append (symbol *sym, location loc) grammar_symbol_append (sym, loc); } -/* Attach an ACTION to the current rule. If needed, move the previous - action as a mid-rule action. */ +/* Attach an ACTION to the current rule. */ void grammar_current_rule_action_append (const char *action, location loc) { if (current_rule->action) grammar_midrule_action (); + /* After all symbol declarations have been parsed, packgram invokes + translate_rule_action. */ current_rule->action = action; current_rule->action_location = loc; } @@ -429,7 +463,10 @@ packgram (void) while (p) { + int rule_length = 0; symbol *ruleprec = p->ruleprec; + record_merge_function_type (p->merger, p->sym->type_name, + p->merger_declaration_location); rules[ruleno].user_number = ruleno; rules[ruleno].number = ruleno; rules[ruleno].lhs = p->sym; @@ -440,21 +477,32 @@ packgram (void) rules[ruleno].precsym = NULL; rules[ruleno].location = p->location; rules[ruleno].useful = true; - rules[ruleno].action = p->action; + rules[ruleno].action = p->action ? translate_rule_action (p) : NULL; rules[ruleno].action_location = p->action_location; - p = p->next; - while (p && p->sym) + /* If this rule contains midrules, rest assured that + grammar_midrule_action inserted the midrules into grammar before this + rule. Thus, the midrule actions have already been scanned in order to + set `used' flags for this rule's rhs, so grammar_rule_check will work + properly. */ + grammar_rule_check (p); + + for (p = p->next; p && p->sym; p = p->next) { + ++rule_length; + + /* Don't allow rule_length == INT_MAX, since that might + cause confusion with strtol if INT_MAX == LONG_MAX. */ + if (rule_length == INT_MAX) + fatal_at (rules[ruleno].location, _("rule is too long")); + /* item_number = symbol_number. But the former needs to contain more: negative rule numbers. */ ritem[itemno++] = symbol_number_as_item_number (p->sym->number); /* A rule gets by default the precedence and associativity - of the last token in it. */ + of its last token. */ if (p->sym->class == token_sym && default_prec) rules[ruleno].prec = p->sym; - if (p) - p = p->next; } /* If this rule has a %prec, @@ -464,8 +512,11 @@ packgram (void) rules[ruleno].precsym = ruleprec; rules[ruleno].prec = ruleprec; } + /* An item ends by the rule number (negated). */ ritem[itemno++] = rule_number_as_item_number (ruleno); + assert (itemno < ITEM_NUMBER_MAX); ++ruleno; + assert (ruleno < RULE_NUMBER_MAX); if (p) p = p->next; @@ -514,7 +565,7 @@ reader (void) gram__flex_debug = trace_flag & trace_scan; gram_debug = trace_flag & trace_parse; - scanner_initialize (); + gram_scanner_initialize (); gram_parse (); if (! complaint_issued)