X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/ed8e1f68e9743c391f4aba148968ea1e5e960973..e9f87b5b7df2e328d2e4196d276c0d96594c906b:/src/nullable.c diff --git a/src/nullable.c b/src/nullable.c index bbd8e319..f8c9b32e 100644 --- a/src/nullable.c +++ b/src/nullable.c @@ -25,7 +25,7 @@ #include "system.h" #include "getargs.h" -#include "reader.h" +#include "symtab.h" #include "types.h" #include "gram.h" #include "reduce.h" @@ -39,7 +39,7 @@ nullable_print (FILE *out) int i; fputs ("NULLABLE\n", out); for (i = ntokens; i < nsyms; i++) - fprintf (out, "\t%s: %s\n", tags[i], nullable[i] ? "yes" : "no"); + fprintf (out, "\t%s: %s\n", symbols[i]->tag, nullable[i] ? "yes" : "no"); fputs ("\n\n", out); } @@ -57,8 +57,8 @@ set_nullable (void) Hence we must allocate room for useless nonterminals too. */ shorts **rsets = XCALLOC (shorts *, nvars) - ntokens; /* This is said to be more elements than we actually use. - Supposedly nitems - nrules is enough. But why take the risk? */ - shorts *relts = XCALLOC (shorts, nitems + nvars + 1); + Supposedly NRITEMS - NRULES is enough. But why take the risk? */ + shorts *relts = XCALLOC (shorts, nritems + nvars + 1); if (trace_flag) fprintf (stderr, "Entering set_nullable\n"); @@ -69,35 +69,38 @@ set_nullable (void) p = relts; for (ruleno = 1; ruleno < nrules + 1; ++ruleno) - if (ritem[rule_table[ruleno].rhs] > 0) + if (rules[ruleno].useful) { - /* This rule has a non empty RHS. */ - short *r; - int any_tokens = 0; - for (r = ritem + rule_table[ruleno].rhs; *r > 0; ++r) - if (ISTOKEN (*r)) - any_tokens = 1; - - /* This rule has only nonterminals: schedule it for the second - pass. */ - if (!any_tokens) - for (r = ritem + rule_table[ruleno].rhs; *r > 0; ++r) - { - rcount[ruleno]++; - p->next = rsets[*r]; - p->value = ruleno; - rsets[*r] = p; - p++; - } - } - else - { - /* This rule has an empty RHS. */ - assert (ritem[rule_table[ruleno].rhs] == -ruleno); - if (rule_table[ruleno].useful && !nullable[rule_table[ruleno].lhs]) + if (ritem[rules[ruleno].rhs] >= 0) + { + /* This rule has a non empty RHS. */ + short *r; + int any_tokens = 0; + for (r = &ritem[rules[ruleno].rhs]; *r >= 0; ++r) + if (ISTOKEN (*r)) + any_tokens = 1; + + /* This rule has only nonterminals: schedule it for the second + pass. */ + if (!any_tokens) + for (r = &ritem[rules[ruleno].rhs]; *r >= 0; ++r) + { + rcount[ruleno]++; + p->next = rsets[*r]; + p->value = ruleno; + rsets[*r] = p; + p++; + } + } + else { - nullable[rule_table[ruleno].lhs] = 1; - *s2++ = rule_table[ruleno].lhs; + /* This rule has an empty RHS. */ + assert (ritem[rules[ruleno].rhs] == -ruleno); + if (rules[ruleno].useful && !nullable[rules[ruleno].lhs]) + { + nullable[rules[ruleno].lhs] = 1; + *s2++ = rules[ruleno].lhs; + } } } @@ -106,10 +109,10 @@ set_nullable (void) { ruleno = p->value; if (--rcount[ruleno] == 0) - if (rule_table[ruleno].useful && !nullable[rule_table[ruleno].lhs]) + if (rules[ruleno].useful && !nullable[rules[ruleno].lhs]) { - nullable[rule_table[ruleno].lhs] = 1; - *s2++ = rule_table[ruleno].lhs; + nullable[rules[ruleno].lhs] = 1; + *s2++ = rules[ruleno].lhs; } }