/* Subroutines for bison
- Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc.
+ Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
02111-1307, USA. */
#include "system.h"
-#include "xalloc.h"
+#include "getargs.h"
#include "gram.h"
+#include "reader.h"
#include "closure.h"
#include "derives.h"
#include "warshall.h"
+/* ITEMSETSIZE is the size of the array ITEMSET. */
short *itemset;
-short *itemsetend;
+int itemsetsize;
+
static unsigned *ruleset;
/* internal data. See comments before set_fderives and set_firsts. */
static unsigned *fderives;
static unsigned *firsts;
+#define FDERIVES(Symbol) (fderives + (Symbol) * rulesetsize)
+#define FIRSTS(Symbol) (firsts + (Symbol) * varsetsize)
+
/* number of words required to hold a bit for each rule */
static int rulesetsize;
/* number of words required to hold a bit for each variable */
static int varsetsize;
\f
-#if DEBUG
/*-----------------.
| Debugging code. |
static void
print_closure (int n)
{
- short *isp;
-
- printf ("\n\nn = %d\n\n", n);
- for (isp = itemset; isp < itemsetend; isp++)
- printf (" %d\n", *isp);
+ int i;
+ fprintf (stderr, "n = %d\n", n);
+ for (i = 0; i < itemsetsize; ++i)
+ fprintf (stderr, " %d\n", itemset[i]);
+ fprintf (stderr, "\n\n");
}
int j;
unsigned *rowp;
- printf ("\n\n\nFIRSTS\n\n");
+ fprintf (stderr, "FIRSTS\n");
for (i = ntokens; i < nsyms; i++)
{
- printf ("\n\n%s firsts\n\n", tags[i]);
+ fprintf (stderr, "\t%s firsts\n", tags[i]);
- rowp = firsts + ((i - ntokens) * varsetsize);
+ rowp = FIRSTS (i - ntokens);
for (j = 0; j < nvars; j++)
if (BITISSET (rowp, j))
- printf (" %s\n", tags[j + ntokens]);
+ fprintf (stderr, "\t\t%d (%s)\n", j + ntokens, tags[j + ntokens]);
}
+ fprintf (stderr, "\n\n");
}
int j;
unsigned *rp;
- printf ("\n\n\nFDERIVES\n");
+ fprintf (stderr, "FDERIVES\n");
for (i = ntokens; i < nsyms; i++)
{
- printf ("\n\n%s derives\n\n", tags[i]);
- rp = fderives + i * rulesetsize;
+ fprintf (stderr, "\t%s derives\n", tags[i]);
+ rp = FDERIVES (i);
for (j = 0; j <= nrules; j++)
if (BITISSET (rp, j))
- printf (" %d\n", j);
+ {
+ short *rhsp;
+ fprintf (stderr, "\t\t%d:", j);
+ for (rhsp = ritem + rule_table[j].rhs; *rhsp > 0; ++rhsp)
+ fprintf (stderr, " %s", tags[*rhsp]);
+ fputc ('\n', stderr);
+ }
}
-
- fflush (stdout);
+ fprintf (stderr, "\n\n");
}
-#endif
\f
/*-------------------------------------------------------------------.
| Set FIRSTS to be an NVARS by NVARS bit matrix indicating which |
static void
set_firsts (void)
{
- unsigned *row;
- int symbol;
- short *sp;
int rowsize;
- int i;
+ int i, j;
varsetsize = rowsize = WORDSIZE (nvars);
firsts = XCALLOC (unsigned, nvars * rowsize);
- row = firsts;
for (i = ntokens; i < nsyms; i++)
- {
- sp = derives[i];
- while (*sp >= 0)
- {
- symbol = ritem[rrhs[*sp++]];
- if (ISVAR (symbol))
- {
- symbol -= ntokens;
- SETBIT (row, symbol);
- }
- }
-
- row += rowsize;
- }
+ for (j = 0; derives[i][j] >= 0; ++j)
+ {
+ int symbol = ritem[rule_table[derives[i][j]].rhs];
+ if (ISVAR (symbol))
+ {
+ symbol -= ntokens;
+ SETBIT (FIRSTS (i - ntokens), symbol);
+ }
+ }
RTC (firsts, nvars);
-#ifdef DEBUG
- print_firsts ();
-#endif
+ if (trace_flag)
+ print_firsts ();
}
/*-------------------------------------------------------------------.
set_firsts ();
- rrow = fderives + ntokens * rulesetsize;
+ rrow = FDERIVES (ntokens);
for (i = ntokens; i < nsyms; i++)
{
- vrow = firsts + ((i - ntokens) * varsetsize);
+ vrow = FIRSTS (i - ntokens);
cword = *vrow++;
b = 0;
for (j = ntokens; j < nsyms; j++)
{
rp = derives[j];
while ((ruleno = *rp++) > 0)
- {
- SETBIT (rrow, ruleno);
- }
+ SETBIT (rrow, ruleno);
}
b++;
rrow += rulesetsize;
}
-#ifdef DEBUG
- print_fderives ();
-#endif
+ if (trace_flag)
+ print_fderives ();
XFREE (firsts);
}
void
closure (short *core, int n)
{
- int ruleno;
- unsigned word;
- short *csp;
- unsigned *dsp;
- unsigned *rsp;
+ /* Index over CORE. */
+ int c;
+
+ /* Index over RULESET. */
+ int r;
- short *csend;
- unsigned *rsend;
- int symbol;
- int itemno;
+ /* A bit index over RULESET. */
+ int ruleno;
- rsp = ruleset;
- rsend = ruleset + rulesetsize;
- csend = core + n;
+ if (trace_flag)
+ {
+ fprintf (stderr, "Entering closure (items = {");
+ for (c = 0; c < n; ++c)
+ fprintf (stderr, " %d ", core[c]);
+ fprintf (stderr, "})\n");
+ }
if (n == 0)
{
- dsp = fderives + start_symbol * rulesetsize;
- while (rsp < rsend)
- *rsp++ = *dsp++;
+ for (r = 0; r < rulesetsize; ++r)
+ ruleset[r] = FDERIVES (start_symbol)[r];
}
else
{
- while (rsp < rsend)
- *rsp++ = 0;
+ for (r = 0; r < rulesetsize; ++r)
+ ruleset[r] = 0;
- csp = core;
- while (csp < csend)
- {
- symbol = ritem[*csp++];
- if (ISVAR (symbol))
- {
- dsp = fderives + symbol * rulesetsize;
- rsp = ruleset;
- while (rsp < rsend)
- *rsp++ |= *dsp++;
- }
- }
+ for (c = 0; c < n; ++c)
+ if (ISVAR (ritem[core[c]]))
+ for (r = 0; r < rulesetsize; ++r)
+ ruleset[r] |= FDERIVES (ritem[core[c]])[r];
}
- ruleno = 0;
- itemsetend = itemset;
- csp = core;
- rsp = ruleset;
- while (rsp < rsend)
+ itemsetsize = 0;
+ c = 0;
+ for (ruleno = 0; ruleno < rulesetsize * BITS_PER_WORD; ++ruleno)
+ if (BITISSET (ruleset, ruleno))
+ {
+ int itemno = rule_table[ruleno].rhs;
+ while (c < n && core[c] < itemno)
+ {
+ itemset[itemsetsize] = core[c];
+ itemsetsize++;
+ c++;
+ }
+ itemset[itemsetsize] = itemno;
+ itemsetsize++;
+ }
+
+ while (c < n)
{
- word = *rsp++;
- if (word == 0)
- {
- ruleno += BITS_PER_WORD;
- }
- else
- {
- int b;
-
- for (b = 0; b < BITS_PER_WORD; b++)
- {
- if (word & (1 << b))
- {
- itemno = rrhs[ruleno];
- while (csp < csend && *csp < itemno)
- *itemsetend++ = *csp++;
- *itemsetend++ = itemno;
- }
-
- ruleno++;
- }
- }
+ itemset[itemsetsize] = core[c];
+ itemsetsize++;
+ c++;
}
- while (csp < csend)
- *itemsetend++ = *csp++;
-
-#if DEBUG
- print_closure (n);
-#endif
+ if (trace_flag)
+ print_closure (n);
}
projects / bison.git / blobdiff