in a roundabout way, the bounds of the portion you are trying to
examine.
- Suppose that the portion of yytable starts at index P and the index
+ Suppose that the portion of YYTABLE starts at index P and the index
to be examined within the portion is I. Then if YYCHECK[P+I] != I,
I is outside the bounds of what is actually allocated, and the
default (from YYDEFACT or YYDEFGOTO) should be used. Otherwise,
/* From src/scan-skel.l. */
void m4_invoke PARAMS ((const char *definitions));
+
+/* Several tables will be indexed both by state and nonterminal
+ numbers. We call `vector' such a thing (= either a state or a
+ symbol number.
+
+ Of course vector_number_t ought to be wide enough to contain
+ state_number_t and symbol_number_t. */
+typedef short vector_number_t;
+#define VECTOR_NUMBER_MAX ((vector_number_t) SHRT_MAX)
+#define VECTOR_NUMBER_MIN ((vector_number_t) SHRT_MIN)
+#define state_number_to_vector_number(State) \
+ ((vector_number_t) State)
+#define symbol_number_to_vector_number(Symbol) \
+ ((vector_number_t) (state_number_as_int (nstates) + Symbol - ntokens))
+
static int nvectors;
-static int nentries;
-static state_number_t **froms = NULL;
-static state_number_t **tos = NULL;
+
+
+/* FROMS and TOS are indexed by vector_number_t.
+
+ If VECTOR is a nonterminal, (FROMS[VECTOR], TOS[VECTOR]) form an
+ array of state numbers of the non defaulted GOTO on VECTOR.
+
+ If VECTOR is a state, TOS[VECTOR] is the array of actions to do on
+ the (array of) symbols FROMS[VECTOR].
+
+ In both cases, TALLY[VECTOR] is the size of the arrays
+ FROMS[VECTOR], TOS[VECTOR]; and WIDTH[VECTOR] =
+ (FROMS[VECTOR][SIZE] - FROMS[VECTOR][0] + 1) where SIZE =
+ TALLY[VECTOR].
+
+ FROMS therefore contains symbol_number_t and action_number_t,
+ TOS state_number_t and action_number_t,
+ TALLY sizes,
+ WIDTH differences of FROMS.
+
+ Let base_t be the type of FROMS, TOS, and WIDTH. */
+typedef int base_t;
+#define BASE_MAX ((base_t) INT_MAX)
+#define BASE_MIN ((base_t) INT_MIN)
+
+static base_t **froms = NULL;
+static base_t **tos = NULL;
static unsigned int **conflict_tos = NULL;
static short *tally = NULL;
-static short *width = NULL;
-static short *actrow = NULL;
-static short *conflrow = NULL;
-static short *state_count = NULL;
-static short *order = NULL;
-static short *base = NULL;
-static short *pos = NULL;
+static base_t *width = NULL;
+
+/* For a given state, N = ACTROW[SYMBOL]:
+
+ If N = 0, stands for `run the default action'.
+ If N = MIN, stands for `raise a parse error'.
+ If N > 0, stands for `shift SYMBOL and go to n'.
+ If N < 0, stands for `reduce -N'. */
+typedef short action_t;
+#define ACTION_MAX ((action_t) SHRT_MAX)
+#define ACTION_MIN ((action_t) SHRT_MIN)
+
+static action_t *actrow = NULL;
+
+/* FROMS and TOS are reordered to be compressed. ORDER[VECTOR] is the
+ new vector number of VECTOR. We skip `empty' vectors (i.e.,
+ TALLY[VECTOR] = 0), and call these `entries'. */
+static vector_number_t *order = NULL;
+static int nentries;
+
+static base_t *base = NULL;
+/* A distinguished value of BASE, negative infinite. During the
+ computation equals to BASE_MIN, later mapped to BASE_NINF to
+ keep parser tables small. */
+base_t base_ninf = 0;
+static base_t *pos = NULL;
+
+static unsigned int *conflrow = NULL;
static unsigned int *conflict_table = NULL;
static unsigned int *conflict_list = NULL;
static int conflict_list_cnt;
We start with the original hard-coded value: SHRT_MAX
(yes, not USHRT_MAX). */
static size_t table_size = SHRT_MAX;
-static short *table = NULL;
-static short *check = NULL;
+static base_t *table = NULL;
+static base_t *check = NULL;
+/* The value used in TABLE to denote explicit parse errors
+ (%nonassoc), a negative infinite. First defaults to ACTION_MIN,
+ but in order to keep small tables, renumbered as TABLE_ERROR, which
+ is the smallest (non error) value minus 1. */
+base_t table_ninf = 0;
static int lowzero;
static int high;
fprintf (stderr, "growing table and check from: %d to %d\n",
old_size, table_size);
- table = XREALLOC (table, short, table_size);
- check = XREALLOC (check, short, table_size);
+ table = XREALLOC (table, base_t, table_size);
+ check = XREALLOC (check, base_t, table_size);
if (glr_parser)
conflict_table = XREALLOC (conflict_table, unsigned int, table_size);
int begin, \
int end) \
{ \
+ Type min = first; \
Type max = first; \
int i; \
int j = 1; \
else \
++j; \
obstack_fgrow1 (&format_obstack, "%6d", table_data[i]); \
- if (table_data[i] > max) \
+ if (table_data[i] < min) \
+ min = table_data[i]; \
+ if (max < table_data[i]) \
max = table_data[i]; \
} \
obstack_1grow (&format_obstack, 0); \
muscle_insert (name, obstack_finish (&format_obstack)); \
\
- /* Build `NAME_max' in the obstack. */ \
+ /* Build `NAME_min' and `NAME_max' in the obstack. */ \
+ obstack_fgrow1 (&format_obstack, "%s_min", name); \
+ obstack_1grow (&format_obstack, 0); \
+ MUSCLE_INSERT_LONG_INT (obstack_finish (&format_obstack), \
+ (long int) min); \
obstack_fgrow1 (&format_obstack, "%s_max", name); \
obstack_1grow (&format_obstack, 0); \
MUSCLE_INSERT_LONG_INT (obstack_finish (&format_obstack), \
}
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_unsigned_int_table, unsigned int)
+GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_int_table, int)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_short_table, short)
+GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_base_table, base_t)
+GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_rule_number_table, rule_number_t)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_symbol_number_table, symbol_number_t)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_item_number_table, item_number_t)
GENERATE_MUSCLE_INSERT_TABLE(muscle_insert_state_number_table, state_number_t)
muscle_insert ("tname", obstack_finish (&format_obstack));
}
- /* Output YYTOKNUM. */
+ /* Output YYTOKNUM. */
{
int i;
- short *values = XCALLOC (short, ntokens + 1);
+ int *values = XCALLOC (int, ntokens + 1);
for (i = 0; i < ntokens + 1; ++i)
values[i] = symbols[i]->user_token_number;
- muscle_insert_short_table ("toknum", values,
- 0, 1, ntokens + 1);
+ muscle_insert_int_table ("toknum", values,
+ 0, 1, ntokens + 1);
free (values);
}
}
/*-------------------------------------------------------------------.
| For GLR parsers, for each conflicted token in STATE, as indicated |
-| by non-zero entries in conflrow, create a list of possible |
+| by non-zero entries in CONFLROW, create a list of possible |
| reductions that are alternatives to the shift or reduction |
| currently recorded for that token in STATE. Store the alternative |
| reductions followed by a 0 in conflict_list, updating |
| conflict_list_cnt, and storing an index to the start of the list |
-| back into conflrow. |
+| back into CONFLROW. |
`-------------------------------------------------------------------*/
static void
{
conflrow[j] = conflict_list_cnt;
- /* find all reductions for token j, and record all that do
- * not match actrow[j] */
+ /* Find all reductions for token J, and record all that do not
+ match ACTROW[J]. */
for (i = 0; i < state->nlookaheads; i += 1)
if (bitset_test (state->lookaheads[i], j)
- && actrow[j] != -state->lookaheads_rule[i]->number)
+ && (actrow[j]
+ != rule_number_as_item_number (state->lookaheads_rule[i]->number)))
{
assert (conflict_list_free > 0);
conflict_list[conflict_list_cnt]
conflict_list_free -= 1;
}
- /* Leave a 0 at the end */
+ /* Leave a 0 at the end. */
assert (conflict_list_free > 0);
conflict_list_cnt += 1;
conflict_list_free -= 1;
/*------------------------------------------------------------------.
| Decide what to do for each type of token if seen as the lookahead |
| token in specified state. The value returned is used as the |
-| default action (yydefact) for the state. In addition, actrow is |
+| default action (yydefact) for the state. In addition, ACTROW is |
| filled with what to do for each kind of token, index by symbol |
| number, with zero meaning do the default action. The value |
-| SHRT_MIN, a very negative number, means this situation is an |
+| ACTION_MIN, a very negative number, means this situation is an |
| error. The parser recognizes this value specially. |
| |
| This is where conflicts are resolved. The loop over lookahead |
| rules considered lower-numbered rules last, and the last rule |
| considered that likes a token gets to handle it. |
-| |
-| For GLR parsers, also sets conflrow[SYM] to an index into |
+| |
+| For GLR parsers, also sets CONFLROW[SYM] to an index into |
| conflict_list iff there is an unresolved conflict (s/r or r/r) |
| with symbol SYM. The default reduction is not used for a symbol |
-| that has any such conflicts. |
+| that has any such conflicts. |
`------------------------------------------------------------------*/
-static int
+static rule_number_t
action_row (state_t *state)
{
int i;
token follows. */
if (actrow[j] != 0)
conflicted = conflrow[j] = 1;
- actrow[j] = -state->lookaheads_rule[i]->number;
+ actrow[j] = rule_number_as_item_number (state->lookaheads_rule[i]->number);
}
}
}
/* See which tokens are an explicit error in this state (due to
- %nonassoc). For them, record SHRT_MIN as the action. */
+ %nonassoc). For them, record ACTION_MIN as the action. */
for (i = 0; i < errp->num; i++)
{
symbol_number_t symbol = errp->symbols[i];
- actrow[symbol] = SHRT_MIN;
+ actrow[symbol] = ACTION_MIN;
}
/* Now find the most common reduction and make it the default action
symbol_number_t j;
for (j = 0; j < ntokens; j++)
- if (actrow[j] == -rule)
+ if (actrow[j] == rule_number_as_item_number (rule))
count++;
if (count > max)
{
int j;
for (j = 0; j < ntokens; j++)
- if (actrow[j] == -default_rule
+ if (actrow[j] == rule_number_as_item_number (default_rule)
&& ! (glr_parser && conflrow[j]))
actrow[j] = 0;
}
if (default_rule == 0)
for (i = 0; i < ntokens; i++)
- if (actrow[i] == SHRT_MIN)
+ if (actrow[i] == ACTION_MIN)
actrow[i] = 0;
if (conflicted)
}
+/*--------------------------------------------.
+| Set FROMS, TOS, TALLY and WIDTH for STATE. |
+`--------------------------------------------*/
+
static void
save_row (state_number_t state)
{
symbol_number_t i;
int count;
- short *sp = NULL;
- short *sp1 = NULL;
- short *sp2 = NULL;
+ base_t *sp = NULL;
+ base_t *sp1 = NULL;
+ base_t *sp2 = NULL;
unsigned int *sp3 = NULL;
+ /* Number of non default actions in STATE. */
count = 0;
for (i = 0; i < ntokens; i++)
if (actrow[i] != 0)
if (count == 0)
return;
- froms[state] = sp1 = sp = XCALLOC (short, count);
- tos[state] = sp2 = XCALLOC (short, count);
+ /* Allocate non defaulted actions. */
+ froms[state] = sp1 = sp = XCALLOC (base_t, count);
+ tos[state] = sp2 = XCALLOC (base_t, count);
if (glr_parser)
conflict_tos[state] = sp3 = XCALLOC (unsigned int, count);
else
conflict_tos[state] = NULL;
+ /* Store non defaulted actions. */
for (i = 0; i < ntokens; i++)
if (actrow[i] != 0)
{
state_number_t i;
int nconflict = conflicts_total_count ();
- short *yydefact = XCALLOC (short, nstates);
+ rule_number_t *yydefact = XCALLOC (rule_number_t, nstates);
- actrow = XCALLOC (short, ntokens);
+ actrow = XCALLOC (action_t, ntokens);
+ conflrow = XCALLOC (unsigned int, ntokens);
- conflrow = XCALLOC (short, ntokens);
if (glr_parser)
{
conflict_list = XCALLOC (unsigned int, 1 + 2 * nconflict);
save_row (i);
}
- muscle_insert_short_table ("defact", yydefact,
- yydefact[0], 1, nstates);
+ muscle_insert_rule_number_table ("defact", yydefact,
+ yydefact[0], 1, nstates);
XFREE (actrow);
XFREE (conflrow);
XFREE (yydefact);
}
+/*------------------------------------------------------------------.
+| Compute FROMS[VECTOR], TOS[VECTOR], TALLY[VECTOR], WIDTH[VECTOR], |
+| i.e., the information related to non defaulted GOTO on the nterm |
+| SYMBOL. |
+| |
+| DEFAULT_STATE is the principal destination on SYMBOL, i.e., the |
+| default GOTO destination on SYMBOL. |
+`------------------------------------------------------------------*/
+
static void
save_column (symbol_number_t symbol, state_number_t default_state)
{
int i;
- state_number_t *sp;
- state_number_t *sp1;
- state_number_t *sp2;
+ base_t *sp;
+ base_t *sp1;
+ base_t *sp2;
int count;
- int symno = symbol - ntokens + state_number_as_int (nstates);
+ vector_number_t symno = symbol_number_to_vector_number (symbol);
goto_number_t begin = goto_map[symbol];
goto_number_t end = goto_map[symbol + 1];
+ /* Number of non default GOTO. */
count = 0;
for (i = begin; i < end; i++)
if (to_state[i] != default_state)
if (count == 0)
return;
- froms[symno] = sp1 = sp = XCALLOC (short, count);
- tos[symno] = sp2 = XCALLOC (short, count);
+ /* Allocate room for non defaulted gotos. */
+ froms[symno] = sp1 = sp = XCALLOC (base_t, count);
+ tos[symno] = sp2 = XCALLOC (base_t, count);
+ /* Store the state numbers of the non defaulted gotos. */
for (i = begin; i < end; i++)
if (to_state[i] != default_state)
{
}
+/*----------------------------------------------------------------.
+| Return `the' most common destination GOTO on SYMBOL (a nterm). |
+`----------------------------------------------------------------*/
+
static state_number_t
-default_goto (symbol_number_t symbol)
+default_goto (symbol_number_t symbol, short state_count[])
{
state_number_t s;
int i;
goto_actions (void)
{
symbol_number_t i;
- state_number_t *yydefgoto = XMALLOC (state_number_t, nsyms - ntokens);
+ state_number_t *yydefgoto = XMALLOC (state_number_t, nvars);
- state_count = XCALLOC (short, nstates);
+ /* For a given nterm I, STATE_COUNT[S] is the number of times there
+ is a GOTO to S on I. */
+ short *state_count = XCALLOC (short, nstates);
for (i = ntokens; i < nsyms; ++i)
{
- state_number_t default_state = default_goto (i);
+ state_number_t default_state = default_goto (i, state_count);
save_column (i, default_state);
yydefgoto[i - ntokens] = default_state;
}
}
-/* The next few functions decide how to pack the actions and gotos
- information into yytable. */
+/*------------------------------------------------------------------.
+| Compute ORDER, a reordering of vectors, in order to decide how to |
+| pack the actions and gotos information into yytable. |
+`------------------------------------------------------------------*/
static void
sort_actions (void)
}
-static int
-matching_state (int vector)
+/* If VECTOR is a state which actions (reflected by FROMS, TOS, TALLY
+ and WIDTH of VECTOR) are common to a previous state, return this
+ state number.
+
+ In any other case, return -1. */
+
+static state_number_t
+matching_state (vector_number_t vector)
{
- int i = order[vector];
+ vector_number_t i = order[vector];
int t;
int w;
int prev;
+ /* If VECTOR is a nterm, return -1. */
if (i >= (int) nstates)
return -1;
for (prev = vector - 1; prev >= 0; prev--)
{
- int j = order[prev];
+ vector_number_t j = order[prev];
int k;
int match = 1;
+ /* Given how ORDER was computed, if the WIDTH or TALLY is
+ different, there cannot be a matching state. */
if (width[j] != w || tally[j] != t)
return -1;
}
-static int
-pack_vector (int vector)
+static base_t
+pack_vector (vector_number_t vector)
{
- int i = order[vector];
+ vector_number_t i = order[vector];
int j;
int t = tally[i];
int loc = 0;
- short *from = froms[i];
- short *to = tos[i];
+ base_t *from = froms[i];
+ base_t *to = tos[i];
unsigned int *conflict_to = conflict_tos[i];
assert (t);
{
for (k = 0; k < t; k++)
{
- loc = j + state_number_as_int (from[k]);
- table[loc] = state_number_as_int (to[k]);
+ loc = j + from[k];
+ table[loc] = to[k];
if (glr_parser && conflict_to != NULL)
conflict_table[loc] = conflict_to[k];
- check[loc] = state_number_as_int (from[k]);
+ check[loc] = from[k];
}
while (table[lowzero] != 0)
if (loc > high)
high = loc;
+ if (j < BASE_MIN || BASE_MAX < j)
+ fatal ("base_t too small to hold %d\n", j);
return j;
}
}
}
+/*-------------------------------------------------------------.
+| Remap the negative infinite in TAB from NINF to the greatest |
+| possible smallest value. Return it. |
+| |
+| In most case this allows us to use shorts instead of ints in |
+| parsers. |
+`-------------------------------------------------------------*/
+
+static base_t
+table_ninf_remap (base_t tab[], size_t size, base_t ninf)
+{
+ base_t res = 0;
+ size_t i;
+
+ for (i = 0; i < size; i++)
+ if (tab[i] < res && tab[i] != ninf)
+ res = base[i];
+
+ --res;
+
+ for (i = 0; i < size; i++)
+ if (tab[i] == ninf)
+ tab[i] = res;
+
+ return res;
+}
+
static void
pack_table (void)
{
int i;
- int place;
- int state;
- base = XCALLOC (short, nvectors);
- pos = XCALLOC (short, nentries);
- table = XCALLOC (short, table_size);
+ base = XCALLOC (base_t, nvectors);
+ pos = XCALLOC (base_t, nentries);
+ table = XCALLOC (base_t, table_size);
if (glr_parser)
conflict_table = XCALLOC (unsigned int, table_size);
- check = XCALLOC (short, table_size);
+ check = XCALLOC (base_t, table_size);
lowzero = 0;
high = 0;
for (i = 0; i < nvectors; i++)
- base[i] = SHRT_MIN;
+ base[i] = BASE_MIN;
for (i = 0; i < (int) table_size; i++)
check[i] = -1;
for (i = 0; i < nentries; i++)
{
- state = matching_state (i);
+ state_number_t state = matching_state (i);
+ base_t place;
if (state < 0)
+ /* A new set of state actions, or a nonterminal. */
place = pack_vector (i);
else
+ /* Action of I were already coded for STATE. */
place = base[state];
pos[i] = place;
base[order[i]] = place;
}
+ /* Use the greatest possible negative infinites. */
+ base_ninf = table_ninf_remap (base, nvectors, BASE_MIN);
+ table_ninf = table_ninf_remap (table, high + 1, ACTION_MIN);
+
for (i = 0; i < nvectors; i++)
{
XFREE (froms[i]);
free (pos);
}
+
/* the following functions output yytable, yycheck, yyconflp, yyconfl,
- and the vectors whose elements index the portion starts */
+ and the vectors whose elements index the portion starts. */
static void
output_base (void)
{
- /* Output pact. */
- muscle_insert_short_table ("pact", base,
+ /* Output PACT. */
+ muscle_insert_base_table ("pact", base,
base[0], 1, nstates);
+ MUSCLE_INSERT_INT ("pact_ninf", base_ninf);
- /* Output pgoto. */
- muscle_insert_short_table ("pgoto", base,
+ /* Output PGOTO. */
+ muscle_insert_base_table ("pgoto", base,
base[nstates], nstates + 1, nvectors);
XFREE (base);
}
static void
output_table (void)
{
- muscle_insert_short_table ("table", table,
- table[0], 1, high + 1);
+ muscle_insert_base_table ("table", table,
+ table[0], 1, high + 1);
+ MUSCLE_INSERT_INT ("table_ninf", table_ninf);
XFREE (table);
}
static void
output_check (void)
{
- muscle_insert_short_table ("check", check,
- check[0], 1, high + 1);
+ muscle_insert_base_table ("check", check,
+ check[0], 1, high + 1);
XFREE (check);
}
nvectors = state_number_as_int (nstates) + nvars;
- froms = XCALLOC (short *, nvectors);
- tos = XCALLOC (short *, nvectors);
+ froms = XCALLOC (base_t *, nvectors);
+ tos = XCALLOC (base_t *, nvectors);
conflict_tos = XCALLOC (unsigned int *, nvectors);
tally = XCALLOC (short, nvectors);
- width = XCALLOC (short, nvectors);
+ width = XCALLOC (base_t, nvectors);
token_actions ();
bitsetv_free (LA);
XFREE (from_state);
XFREE (to_state);
- order = XCALLOC (short, nvectors);
+ order = XCALLOC (vector_number_t, nvectors);
sort_actions ();
pack_table ();
free (order);
/* States. */
MUSCLE_INSERT_INT ("last", high);
- MUSCLE_INSERT_INT ("flag", SHRT_MIN);
MUSCLE_INSERT_INT ("final_state_number", final_state->number);
MUSCLE_INSERT_INT ("states_number", nstates);
projects / bison.git / commitdiff
