X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/d7913476c462b480f11e14b6829942f2691c6c01..cf3b4b64d080d68da634ae1650c42078ff57f464:/src/closure.c diff --git a/src/closure.c b/src/closure.c index 27acf7c5..06c50364 100644 --- a/src/closure.c +++ b/src/closure.c @@ -1,5 +1,5 @@ /* Subroutines for bison - Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc. + Copyright (C) 1984, 1989, 2000, 2001, 2002 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -19,134 +19,173 @@ 02111-1307, USA. */ #include "system.h" -#include "xalloc.h" +#include "bitset.h" +#include "bitsetv.h" +#include "getargs.h" +#include "symtab.h" #include "gram.h" +#include "reader.h" #include "closure.h" #include "derives.h" -#include "warshall.h" +/* NITEMSET is the size of the array ITEMSET. */ short *itemset; -short *itemsetend; -static unsigned *ruleset; +int nitemset; -/* internal data. See comments before set_fderives and set_firsts. */ -static unsigned *fderives; -static unsigned *firsts; +static bitset ruleset; -/* number of words required to hold a bit for each rule */ -static int rulesetsize; +/* internal data. See comments before set_fderives and set_firsts. */ +static bitsetv fderives = NULL; +static bitsetv firsts = NULL; -/* number of words required to hold a bit for each variable */ -static int varsetsize; +/* Retrieve the FDERIVES/FIRSTS sets of the nonterminals numbered Var. */ +#define FDERIVES(Var) fderives[(Var) - ntokens] +#define FIRSTS(Var) firsts[(Var) - ntokens] -#if DEBUG /*-----------------. | Debugging code. | `-----------------*/ static void -print_closure (int n) +print_closure (const char *title, short *array, size_t size) { - short *isp; - - printf ("\n\nn = %d\n\n", n); - for (isp = itemset; isp < itemsetend; isp++) - printf (" %d\n", *isp); + size_t i; + fprintf (stderr, "Closure: %s\n", title); + for (i = 0; i < size; ++i) + { + short *rp; + fprintf (stderr, " %2d: .", array[i]); + for (rp = &ritem[array[i]]; *rp >= 0; ++rp) + fprintf (stderr, " %s", symbols[*rp]->tag); + fprintf (stderr, " (rule %d)\n", -*rp - 1); + } + fputs ("\n\n", stderr); } static void print_firsts (void) { - int i; - int j; - unsigned *rowp; - - printf ("\n\n\nFIRSTS\n\n"); + int i, j; + fprintf (stderr, "FIRSTS\n"); for (i = ntokens; i < nsyms; i++) { - printf ("\n\n%s firsts\n\n", tags[i]); - - rowp = firsts + ((i - ntokens) * varsetsize); - + fprintf (stderr, "\t%s firsts\n", symbols[i]->tag); for (j = 0; j < nvars; j++) - if (BITISSET (rowp, j)) - printf (" %s\n", tags[j + ntokens]); + if (bitset_test (FIRSTS (i), j)) + fprintf (stderr, "\t\t%d (%s)\n", + j + ntokens, symbols[j + ntokens]->tag); } + fprintf (stderr, "\n\n"); } static void print_fderives (void) { - int i; - int j; - unsigned *rp; - - printf ("\n\n\nFDERIVES\n"); + int i, j; + 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", symbols[i]->tag); for (j = 0; j <= nrules; j++) - if (BITISSET (rp, j)) - printf (" %d\n", j); + if (bitset_test (FDERIVES (i), j)) + { + short *rhsp; + fprintf (stderr, "\t\t%d:", j - 1); + for (rhsp = &ritem[rules[j].rhs]; *rhsp >= 0; ++rhsp) + fprintf (stderr, " %s", symbols[*rhsp]->tag); + fputc ('\n', stderr); + } } + fprintf (stderr, "\n\n"); +} + +/*--------------------------------------------------------. +| Display the MATRIX array of SIZE bitsets of size SIZE. | +`--------------------------------------------------------*/ - fflush (stdout); +static void +bitmatrix_print (const char *title, bitsetv matrix) +{ + size_t i, j; + size_t size = bitset_size (matrix[0]); + + /* Title. */ + fprintf (stderr, "%s BEGIN\n", title); + + /* Column numbers. */ + fputs (" ", stderr); + for (i = 0; i < size; ++i) + putc (i / 10 ? '0' + i / 10 : ' ', stderr); + putc ('\n', stderr); + fputs (" ", stderr); + for (i = 0; i < size; ++i) + fprintf (stderr, "%d", i % 10); + putc ('\n', stderr); + + /* Bar. */ + fputs (" .", stderr); + for (i = 0; i < size; ++i) + putc ('-', stderr); + fputs (".\n", stderr); + + /* Contents. */ + for (i = 0; i < size; ++i) + { + fprintf (stderr, "%2d|", i); + for (j = 0; j < size; ++j) + fputs (bitset_test (matrix[i], j) ? "1" : " ", stderr); + fputs ("|\n", stderr); + } + + /* Bar. */ + fputs (" `", stderr); + for (i = 0; i < size; ++i) + putc ('-', stderr); + fputs ("'\n", stderr); + + /* End title. */ + fprintf (stderr, "%s END\n\n", title); } -#endif -/*-------------------------------------------------------------------. -| 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) { - unsigned *row; - int symbol; - short *sp; - int rowsize; - - int i; + int i, j; - varsetsize = rowsize = WORDSIZE (nvars); + firsts = bitsetv_create (nvars, nvars, BITSET_FIXED); - 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; - } - - RTC (firsts, nvars); - -#ifdef DEBUG - print_firsts (); -#endif + 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); + } + + if (trace_flag) + bitmatrix_print ("RTC: Input", firsts); + bitsetv_reflexive_transitive_closure (firsts); + if (trace_flag) + bitmatrix_print ("RTC: Output", firsts); + + if (trace_flag) + print_firsts (); } /*-------------------------------------------------------------------. @@ -162,54 +201,22 @@ set_firsts (void) static void set_fderives (void) { - unsigned *rrow; - unsigned *vrow; - int j; - unsigned cword; - short *rp; - int b; - - int ruleno; - int i; + int i, j, k; - fderives = XCALLOC (unsigned, nvars * rulesetsize) - ntokens * rulesetsize; + fderives = bitsetv_create (nvars, nrules + 1, BITSET_FIXED); set_firsts (); - rrow = fderives + ntokens * rulesetsize; - - for (i = ntokens; i < nsyms; i++) - { - vrow = firsts + ((i - ntokens) * varsetsize); - cword = *vrow++; - b = 0; - for (j = ntokens; j < nsyms; j++) - { - if (cword & (1 << b)) - { - rp = derives[j]; - while ((ruleno = *rp++) > 0) - { - SETBIT (rrow, ruleno); - } - } - - b++; - if (b >= BITS_PER_WORD && j + 1 < nsyms) - { - cword = *vrow++; - b = 0; - } - } - - rrow += rulesetsize; - } + for (i = ntokens; i < nsyms; ++i) + for (j = ntokens; j < nsyms; ++j) + if (bitset_test (FIRSTS (i), j - ntokens)) + for (k = 0; derives[j][k] > 0; ++k) + bitset_set (FDERIVES (i), derives[j][k]); -#ifdef DEBUG - print_fderives (); -#endif + if (trace_flag) + print_fderives (); - XFREE (firsts); + bitsetv_free (firsts); } @@ -218,8 +225,7 @@ new_closure (int n) { itemset = XCALLOC (short, n); - rulesetsize = WORDSIZE (nrules + 1); - ruleset = XCALLOC (unsigned, rulesetsize); + ruleset = bitset_create (nrules + 1, BITSET_FIXED); set_fderives (); } @@ -229,82 +235,53 @@ new_closure (int n) void closure (short *core, int n) { - int ruleno; - unsigned word; - short *csp; - unsigned *dsp; - unsigned *rsp; + /* Index over CORE. */ + int c; - 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) + print_closure ("input", core, n); if (n == 0) { - dsp = fderives + start_symbol * rulesetsize; - while (rsp < rsend) - *rsp++ = *dsp++; + bitset_copy (ruleset, FDERIVES (start_symbol)); } else { - while (rsp < rsend) - *rsp++ = 0; - - csp = core; - while (csp < csend) - { - symbol = ritem[*csp++]; - if (ISVAR (symbol)) - { - dsp = fderives + symbol * rulesetsize; - rsp = ruleset; - while (rsp < rsend) - *rsp++ |= *dsp++; - } - } + bitset_zero (ruleset); + + for (c = 0; c < n; ++c) + if (ISVAR (ritem[core[c]])) + bitset_or (ruleset, ruleset, FDERIVES (ritem[core[c]])); } - ruleno = 0; - itemsetend = itemset; - csp = core; - rsp = ruleset; - while (rsp < rsend) + nitemset = 0; + c = 0; + for (ruleno = 0; ruleno < nrules + 1; ++ruleno) + if (bitset_test (ruleset, ruleno)) + { + int itemno = rules[ruleno].rhs; + while (c < n && core[c] < itemno) + { + itemset[nitemset] = core[c]; + nitemset++; + c++; + } + itemset[nitemset] = itemno; + nitemset++; + } + + 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[nitemset] = core[c]; + nitemset++; + c++; } - while (csp < csend) - *itemsetend++ = *csp++; - -#if DEBUG - print_closure (n); -#endif + if (trace_flag) + print_closure ("output", itemset, nitemset); } @@ -312,6 +289,6 @@ void free_closure (void) { XFREE (itemset); - XFREE (ruleset); - XFREE (fderives + ntokens * rulesetsize); + bitset_free (ruleset); + bitsetv_free (fderives); }