state. These symbols at these items are the allowable inputs that
can follow now.
- A core represents one state. States are numbered in the number
+ A core represents one state. States are numbered in the NUMBER
field. When generate_states is finished, the starting state is
- state 0 and nstates is the number of states. (A transition to a
- state whose state number is nstates indicates termination.) All
- the cores are chained together and first_state points to the first
- one (state 0).
+ state 0 and NSTATES is the number of states. (FIXME: This sentence
+ is no longer true: A transition to a state whose state number is
+ NSTATES indicates termination.) All the cores are chained together
+ and FIRST_STATE points to the first one (state 0).
For each state there is a particular symbol which must have been
the last thing accepted to reach that state. It is the
- accessing_symbol of the core.
+ ACCESSING_SYMBOL of the core.
- Each core contains a vector of nitems items which are the indices
- in the ritems vector of the items that are selected in this state.
+ Each core contains a vector of NITEMS items which are the indices
+ in the RITEMS vector of the items that are selected in this state.
- The link field is used for chaining buckets that hash states by
+ The link field is used for chaining symbols that hash states by
their itemsets. This is for recognizing equivalent states and
combining them when the states are generated.
#ifndef STATE_H_
# define STATE_H_
-
-/*-------.
-| Core. |
-`-------*/
-
-typedef struct core
-{
- struct core *next;
- struct core *link;
- short number;
- short accessing_symbol;
- short nitems;
- short items[1];
-} core;
-
-#define CORE_ALLOC(Nitems) \
- (core *) xcalloc ((unsigned) (sizeof (core) \
- + (Nitems - 1) * sizeof (short)), 1)
+# include "bitsetv.h"
/*---------.
| Shifts. |
typedef struct shifts
{
- struct shifts *next;
- short number;
short nshifts;
short shifts[1];
} shifts;
-
-#define SHIFTS_ALLOC(Nshifts) \
- (shifts *) xcalloc ((unsigned) (sizeof (shifts) \
- + (Nshifts - 1) * sizeof (short)), 1)
-
-shifts * shifts_new PARAMS ((int n));
+shifts *shifts_new PARAMS ((int n));
/* What is the symbol which is shifted by SHIFTS->shifts[Shift]? Can
case of gotos. */
#define SHIFT_SYMBOL(Shifts, Shift) \
- (state_table[Shifts->shifts[Shift]].accessing_symbol)
+ (states[Shifts->shifts[Shift]]->accessing_symbol)
/* Is the SHIFTS->shifts[Shift] a real shift? (as opposed to gotos.) */
/* Is the SHIFTS->shifts[Shift] then handling of the error token?. */
#define SHIFT_IS_ERROR(Shifts, Shift) \
- (SHIFT_SYMBOL (Shifts, Shift) == error_token_number)
+ (SHIFT_SYMBOL (Shifts, Shift) == errtoken->number)
/* When resolving a SR conflicts, if the reduction wins, the shift is
disabled. */
short errs[1];
} errs;
-#define ERRS_ALLOC(Nerrs) \
- (errs *) xcalloc ((unsigned) (sizeof (errs) \
- + (Nerrs - 1) * sizeof (short)), 1)
+errs *errs_new PARAMS ((int n));
+errs *errs_dup PARAMS ((errs *src));
/*-------------.
typedef struct reductions
{
- struct reductions *next;
- short number;
short nreds;
short rules[1];
} reductions;
-#define REDUCTIONS_ALLOC(Nreductions) \
- (reductions *) xcalloc ((unsigned) (sizeof (reductions) \
- + (Nreductions - 1) * sizeof (short)), 1)
+reductions *reductions_new PARAMS ((int n));
+
+
+/*----------.
+| State_t. |
+`----------*/
+
+typedef struct state_s
+{
+ struct state_s *next;
+ struct state_s *link;
+
+ short number;
+ symbol_number_t accessing_symbol;
+ shifts *shifts;
+ reductions *reductions;
+ errs *errs;
+
+ /* Nonzero if no lookahead is needed to decide what to do in state S. */
+ char consistent;
+
+ /* Used in LALR, not LR(0). */
+ int nlookaheads;
+ bitsetv lookaheads;
+ rule_t **lookaheads_rule;
+
+ /* If some conflicts were solved thanks to precedence/associativity,
+ a human readable description of the resolution. */
+ const char *solved_conflicts;
+
+ /* Its items. Must be last, since ITEMS can be arbitrarily large.
+ */
+ unsigned short nitems;
+ item_number_t items[1];
+} state_t;
+
+#define STATE_ALLOC(Nitems) \
+ (state_t *) xcalloc ((unsigned) (sizeof (state_t) \
+ + (Nitems - 1) * sizeof (item_number_t)), 1)
+
+/* Print on OUT all the lookaheads such that this STATE wants to
+ reduce this RULE. */
+
+void state_rule_lookaheads_print PARAMS ((state_t *state, rule_t *rule,
+ FILE *out));
#endif /* !STATE_H_ */