X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/b2ca4022ea6c61e10ac87a0a92bb0f998ecf8b48..b408954b40e74d85ee90544ea7e296dbc99356c9:/src/state.h?ds=inline diff --git a/src/state.h b/src/state.h index 615c7d5c..95b716d8 100644 --- a/src/state.h +++ b/src/state.h @@ -1,5 +1,5 @@ /* Type definitions for nondeterministic finite state machine for bison, - Copyright (C) 1984, 1989, 2000 Free Software Foundation, Inc. + Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -41,10 +41,10 @@ the last thing accepted to reach that state. It is the accessing_symbol of the core. - Each core contains a vector of nitems items which are the indices + Each core contains a vector of NITEMS items which are the indices in the ritems vector of the items that are selected in this state. - The link field is used for chaining buckets that hash states by + The link field is used for chaining symbols that hash states by their itemsets. This is for recognizing equivalent states and combining them when the states are generated. @@ -88,46 +88,114 @@ #ifndef STATE_H_ # define STATE_H_ -typedef struct core -{ - struct core *next; - struct core *link; - short number; - short accessing_symbol; - short nitems; - short items[1]; -} -core; - +/*---------. +| Shifts. | +`---------*/ typedef struct shifts { - struct shifts *next; - short number; short nshifts; short shifts[1]; -} -shifts; +} shifts; + +shifts *shifts_new PARAMS ((int n)); + + +/* What is the symbol which is shifted by SHIFTS->shifts[Shift]? Can + be a token (amongst which the error token), or non terminals in + case of gotos. */ + +#define SHIFT_SYMBOL(Shifts, Shift) \ + (states[Shifts->shifts[Shift]]->accessing_symbol) + +/* Is the SHIFTS->shifts[Shift] a real shift? (as opposed to gotos.) */ + +#define SHIFT_IS_SHIFT(Shifts, Shift) \ + (ISTOKEN (SHIFT_SYMBOL (Shifts, Shift))) + +/* Is the SHIFTS->shifts[Shift] a goto?. */ + +#define SHIFT_IS_GOTO(Shifts, Shift) \ + (!SHIFT_IS_SHIFT (Shifts, Shift)) + +/* Is the SHIFTS->shifts[Shift] then handling of the error token?. */ +#define SHIFT_IS_ERROR(Shifts, Shift) \ + (SHIFT_SYMBOL (Shifts, Shift) == errtoken->number) +/* When resolving a SR conflicts, if the reduction wins, the shift is + disabled. */ + +#define SHIFT_DISABLE(Shifts, Shift) \ + (Shifts->shifts[Shift] = 0) + +#define SHIFT_IS_DISABLED(Shifts, Shift) \ + (Shifts->shifts[Shift] == 0) + + +/*-------. +| Errs. | +`-------*/ typedef struct errs { short nerrs; short errs[1]; -} -errs; +} errs; +errs *errs_new PARAMS ((int n)); +errs *errs_dup PARAMS ((errs *src)); +/*-------------. +| Reductions. | +`-------------*/ + typedef struct reductions { - struct reductions *next; - short number; short nreds; short rules[1]; -} -reductions; +} reductions; + +reductions *reductions_new PARAMS ((int n)); + + +/*----------. +| State_t. | +`----------*/ + +typedef struct state_s +{ + struct state_s *next; + struct state_s *link; + + short number; + symbol_number_t accessing_symbol; + shifts *shifts; + reductions *reductions; + errs *errs; + + /* Nonzero if no lookahead is needed to decide what to do in state S. */ + char consistent; + + /* Used in LALR, not LR(0). */ + /* Pseudo pointer into LA. */ + short lookaheadsp; + int nlookaheads; + + /* If some conflicts were solved thanks to precedence/associativity, + a human readable description of the resolution. */ + const char *solved_conflicts; + + /* Its items. Must be last, since ITEMS can be arbitrarily large. + */ + unsigned short nitems; + item_number_t items[1]; +} state_t; + +#define STATE_ALLOC(Nitems) \ + (state_t *) xcalloc ((unsigned) (sizeof (state_t) \ + + (Nitems - 1) * sizeof (item_number_t)), 1) #endif /* !STATE_H_ */