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* src/closure.c (firsts): Now, also a bitset.

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Adjust all dependencies.
(varsetsize): Remove, now unused.
* src/warshall.h, src/warshall.c: Now work on arrays of bitsets.
This commit is contained in:
Akim Demaille
2002-03-04 12:03:01 +00:00
parent 34ba97434f
commit d8a0245ce7
4 changed files with 60 additions and 55 deletions
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61
src/closure.c
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@@ -25,8 +25,8 @@
#include "reader.h"
#include "closure.h"
#include "derives.h"
#include "warshall.h"
#include "bitset.h"
#include "warshall.h"
/* NITEMSET is the size of the array ITEMSET. */
short *itemset;
@@ -35,15 +35,12 @@ int nitemset;
static bitset ruleset;
/* internal data. See comments before set_fderives and set_firsts. */
static bitset *fderives;
static unsigned int *firsts;
static bitset *fderives = NULL;
static bitset *firsts = NULL;
/* Retrieve the FDERIVES/FIRSTS sets of the nonterminals numbered Var. */
#define FDERIVES(Var) fderives[(Var) - ntokens]
#define FIRSTS(Var) (firsts + ((Var) - ntokens) * varsetsize)
/* number of words required to hold a bit for each variable */
static int varsetsize;
#define FIRSTS(Var) firsts[(Var) - ntokens]
/*-----------------.
@@ -77,7 +74,7 @@ print_firsts (void)
{
fprintf (stderr, "\t%s firsts\n", symbols[i]->tag);
for (j = 0; j < nvars; j++)
if (BITISSET (FIRSTS (i), j))
if (bitset_test (FIRSTS (i), j))
fprintf (stderr, "\t\t%d (%s)\n",
j + ntokens, symbols[j + ntokens]->tag);
}
@@ -88,11 +85,9 @@ print_firsts (void)
static void
print_fderives (void)
{
int i;
int j;
int i, j;
fprintf (stderr, "FDERIVES\n");
for (i = ntokens; i < nsyms; i++)
{
fprintf (stderr, "\t%s derives\n", symbols[i]->tag);
@@ -109,32 +104,34 @@ print_fderives (void)
fprintf (stderr, "\n\n");
}
/*-------------------------------------------------------------------.
| Set FIRSTS to be an NVARS by NVARS bit matrix indicating which |
| items can represent the beginning of the input corresponding to |
| which other items. |
| |
| For example, if some rule expands symbol 5 into the sequence of |
| symbols 8 3 20, the symbol 8 can be the beginning of the data for |
| symbol 5, so the bit [8 - ntokens, 5 - ntokens] in firsts is set. |
`-------------------------------------------------------------------*/
/*------------------------------------------------------------------.
| Set FIRSTS to be an NVARS array of NVARS bitsets indicating which |
| items can represent the beginning of the input corresponding to |
| which other items. |
| |
| For example, if some rule expands symbol 5 into the sequence of |
| symbols 8 3 20, the symbol 8 can be the beginning of the data for |
| symbol 5, so the bit [8 - ntokens] in first[5 - ntokens] (= FIRST |
| (5)) is set. |
`------------------------------------------------------------------*/
static void
set_firsts (void)
{
int i, j;
varsetsize = WORDSIZE (nvars);
firsts = XCALLOC (unsigned, nvars * varsetsize);
firsts = XCALLOC (bitset, nvars);
for (i = ntokens; i < nsyms; i++)
for (j = 0; derives[i][j] >= 0; ++j)
{
int symbol = ritem[rules[derives[i][j]].rhs];
if (ISVAR (symbol))
SETBIT (FIRSTS (i), symbol - ntokens);
}
{
FIRSTS (i) = bitset_create (nvars, BITSET_FIXED);
bitset_zero (FIRSTS (i));
for (j = 0; derives[i][j] >= 0; ++j)
{
int symbol = ritem[rules[derives[i][j]].rhs];
if (ISVAR (symbol))
bitset_set (FIRSTS (i), symbol - ntokens);
}
}
RTC (firsts, nvars);
@@ -169,13 +166,15 @@ set_fderives (void)
for (i = ntokens; i < nsyms; ++i)
for (j = ntokens; j < nsyms; ++j)
if (BITISSET (FIRSTS (i), j - ntokens))
if (bitset_test (FIRSTS (i), j - ntokens))
for (k = 0; derives[j][k] > 0; ++k)
bitset_set (FDERIVES (i), derives[j][k]);
if (trace_flag)
print_fderives ();
for (i = ntokens; i < nsyms; ++i)
bitset_free (FIRSTS (i));
XFREE (firsts);
}