#include "files.h"
#include "symtab.h"
#include "symlist.h"
-#include "options.h"
#include "gram.h"
#include "complain.h"
#include "output.h"
#include "conflicts.h"
#include "muscle_tab.h"
-int lineno;
static symbol_list_t *grammar = NULL;
static int start_flag = 0;
+merger_list *merge_functions;
/* Nonzero if %union has been seen. */
int typed = 0;
\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 (location_t location)
+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;
+
+ if (type == NULL)
+ type = "";
+
+ 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;
+}
- symbol_t *sym;
+/*--------------------------------------.
+| Free all merge-function definitions. |
+`--------------------------------------*/
- sprintf (buf, "@%d", ++gensym_count);
- sym = getsym (buf, location);
- sym->class = nterm_sym;
- sym->number = nvars++;
- return sym;
+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_t 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 |
grammar_current_rule_check (void)
{
symbol_t *lhs = current_rule->sym;
+ char const *lhs_type = lhs->type_name;
symbol_t *first_rhs = current_rule->next->sym;
/* If there is an action, then there is nothing we can do: the user
- is allowed to shoot in her foot. */
+ is allowed to shoot herself in the foot. */
if (current_rule->action)
return;
- /* If $$ is being set in default way, report if any type mismatch.
- */
+ /* Don't worry about the default action if $$ is untyped, since $$'s
+ value can't be used. */
+ if (! lhs_type)
+ return;
+
+ /* If $$ is being set in default way, report if any type mismatch. */
if (first_rhs)
{
- 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_at (current_rule->location,
}
/* Warn if there is no default for $$ but we need one. */
else
- {
- if (lhs->type_name)
- complain_at (current_rule->location,
- _("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. */
location_t dummy_location = current_rule->action_location;
- symbol_t *dummy = gensym (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
grammar_current_rule_prec_set (symbol_t *precsym, location_t location)
{
if (current_rule->ruleprec)
- complain_at (location, _("two @prec's in a row"));
+ complain_at (location, _("only one %s allowed per rule"), "%prec");
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, _("%s affects only GLR parsers"), "%dprec");
+ if (dprec <= 0)
+ complain_at (location,
+ _("%s must be followed by positive number"), "%dprec");
+ else if (current_rule->dprec != 0)
+ complain_at (location, _("only one %s allowed per rule"), "%dprec");
+ 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, _("%s affects only GLR parsers"), "%merge");
+ if (current_rule->merger != 0)
+ complain_at (location, _("only one %s allowed per rule"), "%merge");
+ 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_t *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;
-
- itemno = 0;
- ruleno = 1;
+ rules = XCALLOC (rule_t, nrules);
- p = grammar;
while (p)
{
symbol_t *ruleprec = p->ruleprec;
rules[ruleno].lhs = p->sym;
rules[ruleno].rhs = ritem + itemno;
rules[ruleno].location = p->location;
- rules[ruleno].useful = TRUE;
+ 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 ("$axiom", empty_location);
- axiom->class = nterm_sym;
- axiom->number = nvars++;
+ /* Construct the accept symbol. */
+ accept = symbol_get ("$accept", empty_location);
+ accept->class = nterm_sym;
+ accept->number = nvars++;
/* Construct the error token */
- errtoken = getsym ("error", empty_location);
+ 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 ("$undefined.", empty_location);
+ undeftoken = symbol_get ("$undefined", empty_location);
undeftoken->class = token_sym;
undeftoken->number = ntokens++;
finput = xfopen (infile, "r");
gram_in = finput;
- gram_debug = !!getenv ("parse");
- gram__flex_debug = !!getenv ("scan");
+ gram__flex_debug = trace_flag & trace_scan;
+ gram_debug = trace_flag & trace_parse;
scanner_initialize ();
gram_parse (&gram_control);
+ /* If something went wrong during the parsing, don't try to
+ continue. */
+ if (complaint_issued)
+ return;
+
/* 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 ("$", empty_location);
- eoftoken->class = token_sym;
- eoftoken->number = 0;
+ endtoken = symbol_get ("$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_t *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;
grammar = p;
}
- if (nsyms > SHRT_MAX)
+ if (SYMBOL_NUMBER_MAX < nsyms)
fatal (_("too many symbols (tokens plus nonterminals); maximum %d"),
- SHRT_MAX);
+ SYMBOL_NUMBER_MAX);
assert (nsyms == ntokens + nvars);
projects / bison.git / blobdiff