#include "getargs.h"
#include "files.h"
#include "symtab.h"
-#include "options.h"
+#include "symlist.h"
#include "gram.h"
#include "complain.h"
#include "output.h"
#include "conflicts.h"
#include "muscle_tab.h"
-int lineno;
-static symbol_list *grammar = NULL;
+static symbol_list_t *grammar = NULL;
static int start_flag = 0;
+merger_list *merge_functions;
/* Nonzero if %union has been seen. */
int typed = 0;
-
-static symbol_list *
-symbol_list_new (symbol_t *sym, location_t location)
-{
- symbol_list *res = XMALLOC (symbol_list, 1);
- res->next = NULL;
- res->sym = sym;
- res->location = location;
- res->action = NULL;
- res->ruleprec = NULL;
- return res;
-}
-
\f
-/*--------------------------------------------------------------.
-| Get the data type (alternative in the union) of the value for |
-| symbol N in rule RULE. |
-`--------------------------------------------------------------*/
-
-char *
-get_type_name (int n, symbol_list *rule)
-{
- int i;
- symbol_list *rp;
-
- if (n < 0)
- {
- complain (_("invalid $ value"));
- return NULL;
- }
-
- rp = rule;
- i = 0;
-
- while (i < n)
- {
- rp = rp->next;
- if (rp == NULL || rp->sym == NULL)
- {
- complain (_("invalid $ value"));
- return NULL;
- }
- ++i;
- }
-
- return rp->sym->type_name;
-}
-
-
/*-----------------------.
| Set the start symbol. |
`-----------------------*/
grammar_start_symbol_set (symbol_t *s, location_t l)
{
if (start_flag)
- complain (_("multiple %s declarations"), "%start");
+ complain_at (l, _("multiple %s declarations"), "%start");
else
{
start_flag = 1;
\f
-/*-------------------------------------------------------------------.
-| Generate a dummy symbol, a nonterminal, whose name cannot conflict |
-| with the user's names. |
+ /*-------------------------------------------------------------------.
+| Return the merger index for a merging function named NAME, whose |
+| arguments have type TYPE. Records the function, if new, in |
+| merger_list. |
`-------------------------------------------------------------------*/
-static symbol_t *
-gensym (void)
+static int
+get_merge_function (const char* name, const char* type,
+ location_t loc)
{
- /* Incremented for each generated symbol */
- static int gensym_count = 0;
- static char buf[256];
+ merger_list *syms;
+ merger_list head;
+ int n;
+
+ if (! glr_parser)
+ return 0;
- symbol_t *sym;
+ if (type == NULL)
+ type = "";
- sprintf (buf, "@%d", ++gensym_count);
- sym = getsym (buf);
- sym->class = nterm_sym;
- sym->number = nvars++;
- return sym;
+ head.next = merge_functions;
+ for (syms = &head, n = 1; syms->next != NULL; syms = syms->next, n += 1)
+ if (strcmp (name, syms->next->name) == 0)
+ break;
+ if (syms->next == NULL)
+ {
+ syms->next = XMALLOC (merger_list, 1);
+ syms->next->name = xstrdup (name);
+ syms->next->type = xstrdup (type);
+ syms->next->next = NULL;
+ merge_functions = head.next;
+ }
+ else if (strcmp (type, syms->next->type) != 0)
+ warn_at (loc, _("result type clash on merge function %s: `%s' vs. `%s'"),
+ name, type, syms->next->type);
+ return n;
}
+
+/*--------------------------------------.
+| Free all merge-function definitions. |
+`--------------------------------------*/
+
+void
+free_merger_functions (void)
+{
+ merger_list *L0;
+ if (! glr_parser)
+ return;
+ L0 = merge_functions;
+ while (L0 != NULL)
+ {
+ merger_list *L1 = L0->next;
+ free (L0);
+ L0 = L1;
+ }
+}
+
\f
/*-------------------------------------------------------------------.
-| Parse the input grammar into a one symbol_list structure. Each |
+| Parse the input grammar into a one symbol_list_t structure. Each |
| rule is represented by a sequence of symbols: the left hand side |
| followed by the contents of the right hand side, followed by a |
| null pointer instead of a symbol to terminate the rule. The next |
`-------------------------------------------------------------------*/
/* The (currently) last symbol of GRAMMAR. */
-symbol_list *grammar_end = NULL;
+symbol_list_t *grammar_end = NULL;
/* Append S to the GRAMMAR. */
void
grammar_symbol_append (symbol_t *symbol, location_t location)
{
- symbol_list *p = symbol_list_new (symbol, location);
+ symbol_list_t *p = symbol_list_new (symbol, location);
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;
-symbol_list *previous_rule_end = NULL;
+symbol_list_t *current_rule = NULL;
+symbol_list_t *previous_rule_end = NULL;
/*----------------------------------------------.
++nvars;
}
else if (lhs->class == token_sym)
- complain (_("rule given for %s, which is a token"), lhs->tag);
+ complain_at (location, _("rule given for %s, which is a token"), lhs->tag);
}
/* Check that the last rule (CURRENT_RULE) is properly defined. For
const char *lhs_type = lhs->type_name ? lhs->type_name : "";
const char *rhs_type = first_rhs->type_name ? first_rhs->type_name : "";
if (strcmp (lhs_type, rhs_type))
- complain (_("type clash (`%s' `%s') on default action"),
- lhs_type, rhs_type);
+ complain_at (current_rule->location,
+ _("type clash (`%s' `%s') on default action"),
+ lhs_type, rhs_type);
}
/* Warn if there is no default for $$ but we need one. */
else
{
if (lhs->type_name)
- complain (_("empty rule for typed nonterminal, and no action"));
+ complain_at (current_rule->location,
+ _("empty rule for typed nonterminal, and no action"));
}
}
/* Make a DUMMY nonterminal, whose location is that of the midrule
action. Create the MIDRULE. */
- symbol_t *dummy = gensym ();
location_t dummy_location = current_rule->action_location;
- symbol_list *midrule = symbol_list_new (dummy, dummy_location);
+ symbol_t *dummy = dummy_symbol_get (dummy_location);
+ symbol_list_t *midrule = symbol_list_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. */
/* Set the precedence symbol of the current rule to PRECSYM. */
void
-grammar_current_rule_prec_set (symbol_t *precsym)
+grammar_current_rule_prec_set (symbol_t *precsym, location_t location)
{
if (current_rule->ruleprec)
- complain (_("two @prec's in a row"));
+ complain_at (location, _("two @prec's in a row"));
current_rule->ruleprec = precsym;
}
+/* Attach dynamic precedence DPREC to the current rule. */
+
+void
+grammar_current_rule_dprec_set (int dprec, location_t location)
+{
+ if (! glr_parser)
+ warn_at (location, _("%%dprec affects only GLR parsers"));
+ if (dprec <= 0)
+ complain_at (location, _("%%dprec must be followed by positive number"));
+ else if (current_rule->dprec != 0)
+ complain_at (location, _("only one %%dprec allowed per rule"));
+ current_rule->dprec = dprec;
+}
+
+/* Attach a merge function NAME with argument type TYPE to current
+ rule. */
+
+void
+grammar_current_rule_merge_set (const char* name, location_t location)
+{
+ if (! glr_parser)
+ warn_at (location, _("%%merge affects only GLR parsers"));
+ if (current_rule->merger != 0)
+ complain_at (location, _("only one %%merge allowed per rule"));
+ current_rule->merger =
+ get_merge_function (name, current_rule->sym->type_name, location);
+}
+
/* Attach a SYMBOL to the current rule. If needed, move the previous
action as a mid-rule action. */
grammar_symbol_append (symbol, location);
}
-
/* Attach an ACTION to the current rule. If needed, move the previous
action as a mid-rule action. */
static void
packgram (void)
{
- unsigned int itemno;
- int ruleno;
- symbol_list *p;
+ unsigned int itemno = 0;
+ rule_number_t ruleno = 0;
+ symbol_list_t *p = grammar;
ritem = XCALLOC (item_number_t, nritems);
- rules = XCALLOC (rule_t, nrules) - 1;
+ rules = XCALLOC (rule_t, nrules);
- itemno = 0;
- ruleno = 1;
-
- p = grammar;
while (p)
{
symbol_t *ruleprec = p->ruleprec;
rules[ruleno].useful = TRUE;
rules[ruleno].action = p->action;
rules[ruleno].action_location = p->action_location;
+ rules[ruleno].dprec = p->dprec;
+ rules[ruleno].merger = p->merger;
p = p->next;
while (p && p->sym)
rules[ruleno].precsym = ruleprec;
rules[ruleno].prec = ruleprec;
}
- ritem[itemno++] = -ruleno;
+ ritem[itemno++] = rule_number_as_item_number (ruleno);
++ruleno;
if (p)
assert (itemno == nritems);
- if (trace_flag)
+ if (trace_flag & trace_sets)
ritem_print (stderr);
}
\f
reader (void)
{
gram_control_t gram_control;
- lineno = 1;
/* Initialize the symbol table. */
symbols_new ();
- /* Construct the axiom symbol. */
- axiom = getsym ("$axiom");
- axiom->class = nterm_sym;
- axiom->number = nvars++;
+ /* Construct the accept symbol. */
+ accept = symbol_get ("$accept", empty_location);
+ accept->class = nterm_sym;
+ accept->number = nvars++;
/* Construct the error token */
- errtoken = getsym ("error");
+ errtoken = symbol_get ("error", empty_location);
errtoken->class = token_sym;
errtoken->number = ntokens++;
/* Construct a token that represents all undefined literal tokens.
It is always token number 2. */
- undeftoken = getsym ("$undefined.");
+ undeftoken = symbol_get ("$undefined", empty_location);
undeftoken->class = token_sym;
undeftoken->number = ntokens++;
scanner_initialize ();
gram_parse (&gram_control);
+ /* If something went wrong during the parsing, don't try to
+ continue. */
+ if (complain_message_count)
+ exit (1);
+
/* Grammar has been read. Do some checking */
if (nrules == 0)
fatal (_("no rules in the input grammar"));
/* Report any undefined symbols and consider them nonterminals. */
symbols_check_defined ();
- /* If the user did not define her EOFTOKEN, do it now. */
- if (!eoftoken)
+ /* If the user did not define her ENDTOKEN, do it now. */
+ if (!endtoken)
{
- eoftoken = getsym ("$");
- eoftoken->class = token_sym;
- eoftoken->number = 0;
+ endtoken = symbol_get ("$end", empty_location);
+ endtoken->class = token_sym;
+ endtoken->number = 0;
/* Value specified by POSIX. */
- eoftoken->user_token_number = 0;
+ endtoken->user_token_number = 0;
}
/* Insert the initial rule, which line is that of the first rule
(not that of the start symbol):
- axiom: %start EOF. */
+ accept: %start EOF. */
{
- symbol_list *p = symbol_list_new (axiom, empty_location);
+ symbol_list_t *p = symbol_list_new (accept, empty_location);
p->location = grammar->location;
p->next = symbol_list_new (startsymbol, empty_location);
- p->next->next = symbol_list_new (eoftoken, empty_location);
+ p->next->next = symbol_list_new (endtoken, empty_location);
p->next->next->next = symbol_list_new (NULL, empty_location);
p->next->next->next->next = grammar;
nrules += 1;
/* Convert the grammar into the format described in gram.h. */
packgram ();
- /* The grammar as a symbol_list is no longer needed. */
- LIST_FREE (symbol_list, grammar);
+ /* The grammar as a symbol_list_t is no longer needed. */
+ LIST_FREE (symbol_list_t, grammar);
}