closure.c File Reference

#include "defs.h"

Include dependency graph for closure.c:

Go to the source code of this file.

Functions
void	set_first_derives (void)
void	closure (short int *nucleus, int n)
void	finalize_closure (void)

Variables
short *	itemset
short *	itemsetend
unsigned *	ruleset

Function Documentation

void closure	(	short int *	nucleus,
		int	n
	)

Definition at line 120 of file closure.c.

{
    int ruleno;
    unsigned word;
    unsigned i;
    short *csp;
    unsigned *dsp;
    unsigned *rsp;
    int rulesetsize;

    short *csend;
    unsigned *rsend;
    int symbol;
    int itemno;

    rulesetsize = WORDSIZE(nrules);
    rsp = ruleset;
    rsend = ruleset + rulesetsize;
    for (rsp = ruleset; rsp < rsend; rsp++)
        *rsp = 0;

    csend = nucleus + n;
    for (csp = nucleus; csp < csend; ++csp)
    {
        symbol = ritem[*csp];
        if (ISVAR(symbol))
        {
            dsp = first_derives + symbol * rulesetsize;
            rsp = ruleset;
            while (rsp < rsend)
                *rsp++ |= *dsp++;
        }
    }

    ruleno = 0;
    itemsetend = itemset;
    csp = nucleus;
    for (rsp = ruleset; rsp < rsend; ++rsp)
    {
        word = *rsp;
        if (word)
        {
            for (i = 0; i < BITS_PER_WORD; ++i)
            {
                if (word & (1 << i))
                {
                    itemno = rrhs[ruleno+i];
                    while (csp < csend && *csp < itemno)
                        *itemsetend++ = *csp++;
                    *itemsetend++ = itemno;
                    while (csp < csend && *csp == itemno)
                        ++csp;
                }
            }
        }
        ruleno += BITS_PER_WORD;
    }

    while (csp < csend)
        *itemsetend++ = *csp++;

#ifdef  DEBUG
  print_closure(n);
#endif
}

void finalize_closure

(

void

)

Definition at line 189 of file closure.c.

{
  FREE(itemset);
  FREE(ruleset);
  FREE(first_derives + ntokens * WORDSIZE(nrules));
}

void set_first_derives

(

void

)

Definition at line 64 of file closure.c.

{
    unsigned *rrow;
    unsigned *vrow;
    int j;
    unsigned k;
    unsigned cword = 0;
    short *rp;

    int rule;
    int i;
    int rulesetsize;
    int varsetsize;

    rulesetsize = WORDSIZE(nrules);
    varsetsize = WORDSIZE(nvars);
    first_derives = NEW2(nvars * rulesetsize, unsigned) - ntokens * rulesetsize;

    set_EFF();

    rrow = first_derives + ntokens * rulesetsize;
    for (i = start_symbol; i < nsyms; i++)
    {
        vrow = EFF + ((i - ntokens) * varsetsize);
        k = BITS_PER_WORD;
        for (j = start_symbol; j < nsyms; k++, j++)
        {
            if (k >= BITS_PER_WORD)
            {
                cword = *vrow++;
                k = 0;
            }

            if (cword & (1 << k))
            {
                rp = derives[j];
                while ((rule = *rp++) >= 0)
                {
                    SETBIT(rrow, rule);
                }
            }
        }

        vrow += varsetsize;
        rrow += rulesetsize;
    }

#ifdef  DEBUG
    print_first_derives();
#endif

    FREE(EFF);
}

Variable Documentation

short* itemset

Definition at line 12 of file closure.c.

short* itemsetend

Definition at line 13 of file closure.c.

unsigned* ruleset

Definition at line 14 of file closure.c.