X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/5edafffd36392c94b6e308f5d4f4eb752a83aa19..dac3c910059dc8a137355d5c58dfd3a9ad6fbbe1:/src/lalr.c diff --git a/src/lalr.c b/src/lalr.c index 150b15e9..be178b8d 100644 --- a/src/lalr.c +++ b/src/lalr.c @@ -33,14 +33,13 @@ #include "derives.h" #include "getargs.h" -/* All the decorated states, indexed by the state number. Warning: - there is a state_TABLE in LR0.c, but it is different and static. - */ +/* All the decorated states, indexed by the state number. */ state_t **state_table = NULL; int tokensetsize; short *LAruleno; unsigned *LA; +size_t nLA; static int ngotos; short *goto_map; @@ -103,7 +102,7 @@ traverse (int i) break; for (k = 0; k < size; ++k) - F (i)[k] = F (j)[k]; + F (j)[k] = F (i)[k]; } } @@ -140,7 +139,7 @@ initialize_LA (void) short *np; reductions *rp; - size_t nLA = state_table[nstates]->lookaheads; + /* Avoid having to special case 0. */ if (!nLA) nLA = 1; @@ -160,12 +159,8 @@ initialize_LA (void) static void set_goto_map (void) { - int state; - int i; - int symbol; - int k; + int state, i; short *temp_map; - int state2; goto_map = XCALLOC (short, nvars + 1) - ntokens; temp_map = XCALLOC (short, nvars + 1) - ntokens; @@ -176,7 +171,7 @@ set_goto_map (void) shifts *sp = state_table[state]->shifts; for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i) { - symbol = state_table[sp->shifts[i]]->accessing_symbol; + int symbol = state_table[sp->shifts[i]]->accessing_symbol; if (ngotos == MAXSHORT) fatal (_("too many gotos (max %d)"), MAXSHORT); @@ -186,18 +181,20 @@ set_goto_map (void) } } - k = 0; - for (i = ntokens; i < nsyms; i++) - { - temp_map[i] = k; - k += goto_map[i]; - } + { + int k = 0; + for (i = ntokens; i < nsyms; i++) + { + temp_map[i] = k; + k += goto_map[i]; + } - for (i = ntokens; i < nsyms; i++) - goto_map[i] = temp_map[i]; + for (i = ntokens; i < nsyms; i++) + goto_map[i] = temp_map[i]; - goto_map[nsyms] = ngotos; - temp_map[nsyms] = ngotos; + goto_map[nsyms] = ngotos; + temp_map[nsyms] = ngotos; + } from_state = XCALLOC (short, ngotos); to_state = XCALLOC (short, ngotos); @@ -207,15 +204,12 @@ set_goto_map (void) shifts *sp = state_table[state]->shifts; for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i) { - for (i = sp->nshifts - 1; i >= 0 && SHIFT_IS_GOTO (sp, i); --i) - { - state2 = sp->shifts[i]; - symbol = state_table[state2]->accessing_symbol; + int state2 = sp->shifts[i]; + int symbol = state_table[state2]->accessing_symbol; - k = temp_map[symbol]++; - from_state[k] = state; - to_state[k] = state2; - } + int k = temp_map[symbol]++; + from_state[k] = state; + to_state[k] = state2; } } @@ -307,30 +301,21 @@ initialize_F (void) static void -add_lookback_edge (int stateno, int ruleno, int gotono) +add_lookback_edge (state_t *state, int ruleno, int gotono) { int i; - int k; - int found; shorts *sp; - i = state_table[stateno]->lookaheads; - k = state_table[stateno + 1]->lookaheads; - found = 0; - while (!found && i < k) - { - if (LAruleno[i] == ruleno) - found = 1; - else - i++; - } + for (i = 0; i < state->nlookaheads; ++i) + if (LAruleno[state->lookaheadsp + i] == ruleno) + break; - assert (found); + assert (LAruleno[state->lookaheadsp + i] == ruleno); sp = XCALLOC (shorts, 1); - sp->next = lookback[i]; + sp->next = lookback[state->lookaheadsp + i]; sp->value = gotono; - lookback[i] = sp; + lookback[state->lookaheadsp + i] = sp; } @@ -432,7 +417,6 @@ build_relations (void) for (i = 0; i < ngotos; i++) { int nedges = 0; - int state1 = from_state[i]; int symbol1 = state_table[to_state[i]]->accessing_symbol; short *rulep; @@ -440,26 +424,26 @@ build_relations (void) { int done; int length = 1; - int stateno = state1; short *rp; - states[0] = state1; + state_t *state = state_table[from_state[i]]; + states[0] = state->number; for (rp = ritem + rule_table[*rulep].rhs; *rp > 0; rp++) { - shifts *sp = state_table[stateno]->shifts; + shifts *sp = state->shifts; int j; for (j = 0; j < sp->nshifts; j++) { - stateno = sp->shifts[j]; - if (state_table[stateno]->accessing_symbol == *rp) + state = state_table[sp->shifts[j]]; + if (state->accessing_symbol == *rp) break; } - states[length++] = stateno; + states[length++] = state->number; } - if (!state_table[stateno]->consistent) - add_lookback_edge (stateno, *rulep, i); + if (!state->consistent) + add_lookback_edge (state, *rulep, i); length--; done = 0; @@ -470,8 +454,7 @@ build_relations (void) /* JF added rp>=ritem && I hope to god its right! */ if (rp >= ritem && ISVAR (*rp)) { - stateno = states[--length]; - edge[nedges++] = map_goto (stateno, *rp); + edge[nedges++] = map_goto (states[--length], *rp); if (nullable[*rp]) done = 0; } @@ -513,10 +496,10 @@ compute_FOLLOWS (void) static void compute_lookaheads (void) { - int i; + size_t i; shorts *sp; - for (i = 0; i < state_table[nstates]->lookaheads; i++) + for (i = 0; i < nLA; i++) for (sp = lookback[i]; sp; sp = sp->next) { int size = LA (i + 1) - LA (i); @@ -526,7 +509,7 @@ compute_lookaheads (void) } /* Free LOOKBACK. */ - for (i = 0; i < state_table[nstates]->lookaheads; i++) + for (i = 0; i < nLA; i++) LIST_FREE (shorts, lookback[i]); XFREE (lookback); @@ -542,18 +525,17 @@ static void initialize_lookaheads (void) { int i; - int count = 0; + nLA = 0; for (i = 0; i < nstates; i++) { int k; + int nlookaheads = 0; reductions *rp = state_table[i]->reductions; shifts *sp = state_table[i]->shifts; - state_table[i]->lookaheads = count; - if (rp && (rp->nreds > 1 || (sp->nshifts && SHIFT_IS_SHIFT (sp, 0)))) - count += rp->nreds; + nlookaheads += rp->nreds; else state_table[i]->consistent = 1; @@ -563,11 +545,11 @@ initialize_lookaheads (void) state_table[i]->consistent = 0; break; } - } - /* Seems to be needed by conflicts.c. */ - state_table[nstates] = STATE_ALLOC (0); - state_table[nstates]->lookaheads = count; + state_table[i]->nlookaheads = nlookaheads; + state_table[i]->lookaheadsp = nLA; + nLA += nlookaheads; + } } void