#include <config.h>
#include "system.h"
+#include <assert.h>
#include <quotearg.h>
#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);
merger_list *merge_functions;
/* Was %union seen? */
-bool typed = false;
+bool union_seen = false;
+
+/* Was a tag seen? */
+bool tag_seen = false;
/* Should rules have a default precedence? */
bool default_prec = true;
}
-/*----------------------------------------------------------------.
-| 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");
\f
-/*-------------------------------------------------------------------.
-| 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;
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))
{
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))
+ {
+ complain_at (declaration_loc,
+ _("result type clash on merge function `%s': <%s> != <%s>"),
+ merge_function->name, type, merge_function->type);
+ complain_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. |
`--------------------------------------*/
static void
grammar_symbol_append (symbol *sym, location loc)
{
- symbol_list *p = symbol_list_new (sym, loc);
+ symbol_list *p = symbol_list_sym_new (sym, loc);
if (grammar_end)
grammar_end->next = p;
/* 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;
void
grammar_current_rule_begin (symbol *lhs, location loc)
{
- if (!start_flag)
- {
- startsymbol = lhs;
- startsymbol_location = loc;
- start_flag = true;
- }
-
/* Start a new rule and record its lhs. */
++nrules;
previous_rule_end = grammar_end;
}
-/*-----------------------------------------------------------------.
-| 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 (symbol_destructor_get (s->content.sym)
|| (s->midrule && s->midrule->used));
}
Don't worry about the default action if $$ is untyped, since $$'s
value can't be used. */
- if (!r->action && r->sym->type_name)
+ if (!r->action && r->content.sym->type_name)
{
- symbol *first_rhs = r->next->sym;
+ symbol *first_rhs = r->next->content.sym;
/* If $$ is being set in default way, report if any type mismatch. */
if (first_rhs)
{
- char const *lhs_type = r->sym->type_name;
+ char const *lhs_type = r->content.sym->type_name;
const char *rhs_type =
first_rhs->type_name ? first_rhs->type_name : "";
if (!UNIQSTR_EQ (lhs_type, rhs_type))
_("empty rule for typed nonterminal, and no action"));
}
- /* Check that typed symbol values are used. */
+ /* Check that symbol values that should be used are in fact used. */
{
symbol_list const *l = r;
int n = 0;
- for (; l && l->sym; l = l->next, ++n)
+ for (; l && l->content.sym; l = l->next, ++n)
if (! (l->used
- || !symbol_typed_p (l)
+ || !symbol_should_be_used (l)
/* The default action, $$ = $1, `uses' both. */
|| (!r->action && (n == 0 || n == 1))))
{
/* 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);
}
| rule. |
`-------------------------------------------------------------------*/
-static void
+void
grammar_midrule_action (void)
{
/* Since the action was written out with this rule's number, we must
action. Create the MIDRULE. */
location dummy_location = current_rule->action_location;
symbol *dummy = dummy_symbol_get (dummy_location);
- symbol_list *midrule = symbol_list_new (dummy, dummy_location);
+ symbol_list *midrule = symbol_list_sym_new (dummy, dummy_location);
/* Make a new rule, whose body is empty, before the current one, so
that the action just read can belong to it. */
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;
grammar = midrule;
/* End the dummy's rule. */
- midrule->next = symbol_list_new (NULL, dummy_location);
- grammar_rule_check (midrule);
+ midrule->next = symbol_list_sym_new (NULL, dummy_location);
midrule->next->next = current_rule;
previous_rule_end = midrule->next;
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. */
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
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;
}
while (p)
{
+ int rule_length = 0;
symbol *ruleprec = p->ruleprec;
+ record_merge_function_type (p->merger, p->content.sym->type_name,
+ p->merger_declaration_location);
rules[ruleno].user_number = ruleno;
rules[ruleno].number = ruleno;
- rules[ruleno].lhs = p->sym;
+ rules[ruleno].lhs = p->content.sym;
rules[ruleno].rhs = ritem + itemno;
rules[ruleno].prec = NULL;
rules[ruleno].dprec = p->dprec;
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. */
+ /* Don't check the generated rule 0. It has no action, so some rhs
+ symbols may appear unused, but the parsing algorithm ensures that
+ %destructor's are invoked appropriately. */
+ if (p != grammar)
+ grammar_rule_check (p);
+
+ for (p = p->next; p && p->content.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);
+ ritem[itemno++] =
+ symbol_number_as_item_number (p->content.sym->number);
/* A rule gets by default the precedence and associativity
- of the last token in it. */
- if (p->sym->class == token_sym && default_prec)
- rules[ruleno].prec = p->sym;
- if (p)
- p = p->next;
+ of its last token. */
+ if (p->content.sym->class == token_sym && default_prec)
+ rules[ruleno].prec = p->content.sym;
}
/* If this rule has a %prec,
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;
gram__flex_debug = trace_flag & trace_scan;
gram_debug = trace_flag & trace_parse;
- scanner_initialize ();
+ gram_scanner_initialize ();
gram_parse ();
if (! complaint_issued)
endtoken->user_token_number = 0;
}
+ /* Find the start symbol if no %start. */
+ if (!start_flag)
+ {
+ symbol_list *node;
+ for (node = grammar;
+ node != NULL && symbol_is_dummy (node->content.sym);
+ node = node->next)
+ {
+ for (node = node->next;
+ node != NULL && node->content.sym != NULL;
+ node = node->next)
+ ;
+ }
+ assert (node != NULL);
+ grammar_start_symbol_set (node->content.sym,
+ node->content.sym->location);
+ }
+
/* Insert the initial rule, whose line is that of the first rule
(not that of the start symbol):
accept: %start EOF. */
{
- symbol_list *p = symbol_list_new (accept, empty_location);
+ symbol_list *p = symbol_list_sym_new (accept, empty_location);
p->location = grammar->location;
- p->next = symbol_list_new (startsymbol, empty_location);
- p->next->next = symbol_list_new (endtoken, empty_location);
- p->next->next->next = symbol_list_new (NULL, empty_location);
+ p->next = symbol_list_sym_new (startsymbol, empty_location);
+ p->next->next = symbol_list_sym_new (endtoken, empty_location);
+ p->next->next->next = symbol_list_sym_new (NULL, empty_location);
p->next->next->next->next = grammar;
nrules += 1;
nritems += 3;
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