X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/2fa6973e6f491950d9b0345c1573888eed8e01d7..648185ab4a265a28758e3b5d9f34c68bdf05fef7:/src/LR0.c diff --git a/src/LR0.c b/src/LR0.c index f0626fed..06ee51f6 100644 --- a/src/LR0.c +++ b/src/LR0.c @@ -1,5 +1,5 @@ /* Generate the nondeterministic finite state machine for bison, - Copyright (C) 1984, 1986, 1989 Free Software Foundation, Inc. + Copyright 1984, 1986, 1989, 2000, 2001 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -23,69 +23,58 @@ The entry point is generate_states. */ #include "system.h" -#include "alloc.h" +#include "getargs.h" +#include "reader.h" #include "gram.h" #include "state.h" #include "complain.h" #include "closure.h" - -extern char *nullable; -extern short *itemset; -extern short *itemsetend; +#include "LR0.h" int nstates; int final_state; -core *first_state; -shifts *first_shift; -reductions *first_reduction; - -extern void generate_states PARAMS ((void)); +core *first_state = NULL; +shifts *first_shift = NULL; +reductions *first_reduction = NULL; -static core *this_state; -static core *last_state; -static shifts *last_shift; -static reductions *last_reduction; +static core *this_state = NULL; +static core *last_state = NULL; +static shifts *last_shift = NULL; +static reductions *last_reduction = NULL; static int nshifts; -static short *shift_symbol; +static short *shift_symbol = NULL; -static short *redset; -static short *shiftset; +static short *redset = NULL; +static short *shiftset = NULL; -static short **kernel_base; -static short **kernel_end; -static short *kernel_items; +static short **kernel_base = NULL; +static int *kernel_size = NULL; +static short *kernel_items = NULL; /* hash table for states, to recognize equivalent ones. */ #define STATE_TABLE_SIZE 1009 -static core **state_table; +static core **state_table = NULL; static void allocate_itemsets (void) { - short *itemp; - int symbol; int i; int count; - short *symbol_count; + short *symbol_count = NULL; count = 0; - symbol_count = NEW2 (nsyms, short); + symbol_count = XCALLOC (short, nsyms); - itemp = ritem; - symbol = *itemp++; - while (symbol) - { - if (symbol > 0) - { - count++; - symbol_count[symbol]++; - } - symbol = *itemp++; - } + for (i = 0; ritem[i]; ++i) + if (ritem[i] > 0) + { + count++; + symbol_count[ritem[i]]++; + } /* See comments before new_itemsets. All the vectors of items live inside KERNEL_ITEMS. The number of active items after @@ -93,8 +82,9 @@ allocate_itemsets (void) appears as an item, which is symbol_count[symbol]. We allocate that much space for each symbol. */ - kernel_base = NEW2 (nsyms, short *); - kernel_items = NEW2 (count, short); + kernel_base = XCALLOC (short *, nsyms); + if (count) + kernel_items = XCALLOC (short, count); count = 0; for (i = 0; i < nsyms; i++) @@ -104,7 +94,7 @@ allocate_itemsets (void) } shift_symbol = symbol_count; - kernel_end = NEW2 (nsyms, short *); + kernel_size = XCALLOC (int, nsyms); } @@ -113,22 +103,22 @@ allocate_storage (void) { allocate_itemsets (); - shiftset = NEW2 (nsyms, short); - redset = NEW2 (nrules + 1, short); - state_table = NEW2 (STATE_TABLE_SIZE, core *); + shiftset = XCALLOC (short, nsyms); + redset = XCALLOC (short, nrules + 1); + state_table = XCALLOC (core *, STATE_TABLE_SIZE); } static void free_storage (void) { - FREE (shift_symbol); - FREE (redset); - FREE (shiftset); - FREE (kernel_base); - FREE (kernel_end); - FREE (kernel_items); - FREE (state_table); + XFREE (shift_symbol); + XFREE (redset); + XFREE (shiftset); + XFREE (kernel_base); + XFREE (kernel_size); + XFREE (kernel_items); + XFREE (state_table); } @@ -142,8 +132,7 @@ free_storage (void) | shift_symbol is set to a vector of the symbols that can be | | shifted. For each symbol in the grammar, kernel_base[symbol] | | points to a vector of item numbers activated if that symbol is | -| shifted, and kernel_end[symbol] points after the end of that | -| vector. | +| shifted, and kernel_size[symbol] is their numbers. | `----------------------------------------------------------------*/ static void @@ -151,37 +140,29 @@ new_itemsets (void) { int i; int shiftcount; - short *isp; - short *ksp; - int symbol; -#if TRACE - fprintf (stderr, "Entering new_itemsets\n"); -#endif + if (trace_flag) + fprintf (stderr, "Entering new_itemsets, state = %d\n", + this_state->number); for (i = 0; i < nsyms; i++) - kernel_end[i] = NULL; + kernel_size[i] = 0; shiftcount = 0; - isp = itemset; - - while (isp < itemsetend) + for (i = 0; i < itemsetsize; ++i) { - i = *isp++; - symbol = ritem[i]; + int symbol = ritem[itemset[i]]; if (symbol > 0) { - ksp = kernel_end[symbol]; - - if (!ksp) + if (!kernel_size[symbol]) { - shift_symbol[shiftcount++] = symbol; - ksp = kernel_base[symbol]; + shift_symbol[shiftcount] = symbol; + shiftcount++; } - *ksp++ = i + 1; - kernel_end[symbol] = ksp; + kernel_base[symbol][kernel_size[symbol]] = itemset[i] + 1; + kernel_size[symbol]++; } } @@ -198,36 +179,24 @@ new_itemsets (void) static core * new_state (int symbol) { - int n; core *p; - short *isp1; - short *isp2; - short *iend; -#if TRACE - fprintf (stderr, "Entering new_state, symbol = %d\n", symbol); -#endif + if (trace_flag) + fprintf (stderr, "Entering new_state, state = %d, symbol = %d (%s)\n", + this_state->number, symbol, tags[symbol]); if (nstates >= MAXSHORT) fatal (_("too many states (max %d)"), MAXSHORT); - isp1 = kernel_base[symbol]; - iend = kernel_end[symbol]; - n = iend - isp1; - - p = - (core *) xmalloc ((unsigned) (sizeof (core) + (n - 1) * sizeof (short))); + p = CORE_ALLOC (kernel_size[symbol]); p->accessing_symbol = symbol; p->number = nstates; - p->nitems = n; + p->nitems = kernel_size[symbol]; - isp2 = p->items; - while (isp1 < iend) - *isp2++ = *isp1++; + shortcpy (p->items, kernel_base[symbol], kernel_size[symbol]); last_state->next = p; last_state = p; - nstates++; return p; @@ -237,54 +206,39 @@ new_state (int symbol) /*--------------------------------------------------------------. | Find the state number for the state we would get to (from the | | current state) by shifting symbol. Create a new state if no | -| equivalent one exists already. Used by append_states. | +| equivalent one exists already. Used by append_states. | `--------------------------------------------------------------*/ static int get_state (int symbol) { int key; - short *isp1; - short *isp2; - short *iend; + int i; core *sp; - int found; - - int n; -#if TRACE - fprintf (stderr, "Entering get_state, symbol = %d\n", symbol); -#endif + if (trace_flag) + fprintf (stderr, "Entering get_state, state = %d, symbol = %d (%s)\n", + this_state->number, symbol, tags[symbol]); - isp1 = kernel_base[symbol]; - iend = kernel_end[symbol]; - n = iend - isp1; - - /* add up the target state's active item numbers to get a hash key */ + /* Add up the target state's active item numbers to get a hash key. + */ key = 0; - while (isp1 < iend) - key += *isp1++; - + for (i = 0; i < kernel_size[symbol]; ++i) + key += kernel_base[symbol][i]; key = key % STATE_TABLE_SIZE; - sp = state_table[key]; if (sp) { - found = 0; + int found = 0; while (!found) { - if (sp->nitems == n) + if (sp->nitems == kernel_size[symbol]) { found = 1; - isp1 = kernel_base[symbol]; - isp2 = sp->items; - - while (found && isp1 < iend) - { - if (*isp1++ != *isp2++) - found = 0; - } + for (i = 0; i < kernel_size[symbol]; ++i) + if (kernel_base[symbol][i] != sp->items[i]) + found = 0; } if (!found) @@ -306,6 +260,9 @@ get_state (int symbol) state_table[key] = sp = new_state (symbol); } + if (trace_flag) + fprintf (stderr, "Exiting get_state => %d\n", sp->number); + return sp->number; } @@ -323,9 +280,9 @@ append_states (void) int j; int symbol; -#if TRACE - fprintf (stderr, "Entering append_states\n"); -#endif + if (trace_flag) + fprintf (stderr, "Entering append_states, state = %d\n", + this_state->number); /* first sort shift_symbol into increasing order */ @@ -342,20 +299,14 @@ append_states (void) } for (i = 0; i < nshifts; i++) - { - symbol = shift_symbol[i]; - shiftset[i] = get_state (symbol); - } + shiftset[i] = get_state (shift_symbol[i]); } static void new_states (void) { - core *p; - - p = (core *) xmalloc ((unsigned) (sizeof (core) - sizeof (short))); - first_state = last_state = this_state = p; + first_state = last_state = this_state = CORE_ALLOC (0); nstates = 1; } @@ -363,34 +314,18 @@ new_states (void) static void save_shifts (void) { - shifts *p; - short *sp1; - short *sp2; - short *send; - - p = (shifts *) xmalloc ((unsigned) (sizeof (shifts) + - (nshifts - 1) * sizeof (short))); + shifts *p = SHIFTS_ALLOC (nshifts); p->number = this_state->number; p->nshifts = nshifts; - sp1 = shiftset; - sp2 = p->shifts; - send = shiftset + nshifts; - - while (sp1 < send) - *sp2++ = *sp1++; + shortcpy (p->shifts, shiftset, nshifts); if (last_shift) - { - last_shift->next = p; - last_shift = p; - } + last_shift->next = p; else - { - first_shift = p; - last_shift = p; - } + first_shift = p; + last_shift = p; } @@ -405,7 +340,7 @@ insert_start_shift (void) core *statep; shifts *sp; - statep = (core *) xmalloc ((unsigned) (sizeof (core) - sizeof (short))); + statep = CORE_ALLOC (0); statep->number = nstates; statep->accessing_symbol = start_symbol; @@ -413,7 +348,7 @@ insert_start_shift (void) last_state = statep; /* Make a shift from this state to (what will be) the final state. */ - sp = NEW (shifts); + sp = SHIFTS_ALLOC (1); sp->number = nstates++; sp->nshifts = 1; sp->shifts[0] = nstates; @@ -470,10 +405,7 @@ augment_automaton (void) if (sp && sp->number == k) { - sp2 = (shifts *) xmalloc ((unsigned) (sizeof (shifts) - + - sp->nshifts * - sizeof (short))); + sp2 = SHIFTS_ALLOC (sp->nshifts + 1); sp2->number = k; sp2->nshifts = sp->nshifts + 1; sp2->shifts[0] = nstates; @@ -486,11 +418,11 @@ augment_automaton (void) sp1->next = sp2; if (sp == last_shift) last_shift = sp2; - FREE (sp); + XFREE (sp); } else { - sp2 = NEW (shifts); + sp2 = SHIFTS_ALLOC (1); sp2->number = k; sp2->nshifts = 1; sp2->shifts[0] = nstates; @@ -509,8 +441,7 @@ augment_automaton (void) going to the next-to-final state (yet to be made). */ sp = first_shift; - sp2 = (shifts *) xmalloc (sizeof (shifts) - + sp->nshifts * sizeof (short)); + sp2 = SHIFTS_ALLOC (sp->nshifts + 1); sp2->nshifts = sp->nshifts + 1; /* Stick this shift into the vector at the proper place. */ @@ -532,7 +463,7 @@ augment_automaton (void) if (last_shift == sp) last_shift = sp2; - FREE (sp); + XFREE (sp); /* Create the next-to-final state, with shift to what will be the final state. */ @@ -543,7 +474,7 @@ augment_automaton (void) { /* The initial state didn't even have any shifts. Give it one shift, to the next-to-final state. */ - sp = NEW (shifts); + sp = SHIFTS_ALLOC (1); sp->nshifts = 1; sp->shifts[0] = nstates; @@ -561,7 +492,7 @@ augment_automaton (void) /* There are no shifts for any state. Make one shift, from the initial state to the next-to-final state. */ - sp = NEW (shifts); + sp = SHIFTS_ALLOC (1); sp->nshifts = 1; sp->shifts[0] = nstates; @@ -577,13 +508,13 @@ augment_automaton (void) /* Make the final state--the one that follows a shift from the next-to-final state. The symbol for that shift is 0 (end-of-file). */ - statep = (core *) xmalloc ((unsigned) (sizeof (core) - sizeof (short))); + statep = CORE_ALLOC (0); statep->number = nstates; last_state->next = statep; last_state = statep; /* Make the shift from the final state to the termination state. */ - sp = NEW (shifts); + sp = SHIFTS_ALLOC (1); sp->number = nstates++; sp->nshifts = 1; sp->shifts[0] = nstates; @@ -595,7 +526,7 @@ augment_automaton (void) final_state = nstates; /* Make the termination state. */ - statep = (core *) xmalloc ((unsigned) (sizeof (core) - sizeof (short))); + statep = CORE_ALLOC (0); statep->number = nstates++; last_state->next = statep; last_state = statep; @@ -611,21 +542,15 @@ augment_automaton (void) static void save_reductions (void) { - short *isp; - short *rp1; - short *rp2; - int item; int count; - reductions *p; - - short *rend; + int i; /* Find and count the active items that represent ends of rules. */ count = 0; - for (isp = itemset; isp < itemsetend; isp++) + for (i = 0; i < itemsetsize; ++i) { - item = ritem[*isp]; + int item = ritem[itemset[i]]; if (item < 0) redset[count++] = -item; } @@ -634,29 +559,18 @@ save_reductions (void) if (count) { - p = (reductions *) xmalloc ((unsigned) (sizeof (reductions) + - (count - 1) * sizeof (short))); + reductions *p = REDUCTIONS_ALLOC (count); p->number = this_state->number; p->nreds = count; - rp1 = redset; - rp2 = p->rules; - rend = rp1 + count; - - for (/* nothing */; rp1 < rend; ++rp1, ++rp2) - *rp2 = *rp1; + shortcpy (p->rules, redset, count); if (last_reduction) - { - last_reduction->next = p; - last_reduction = p; - } + last_reduction->next = p; else - { - first_reduction = p; - last_reduction = p; - } + first_reduction = p; + last_reduction = p; } }