X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/76290368d48b584808a120dfbd415be93aef04f6..0fe9720964da510a2b359af390a3053aace65f9f:/src/scan-code.h?ds=sidebyside diff --git a/src/scan-code.h b/src/scan-code.h index a60ba9f7..b41d42e3 100644 --- a/src/scan-code.h +++ b/src/scan-code.h @@ -1,12 +1,12 @@ -/* Bison Code Data Structure and Scanner. +/* Bison code properties structure and scanner. - Copyright (C) 2006 Free Software Foundation, Inc. + Copyright (C) 2006-2007, 2009-2012 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. - This program is free software; you can redistribute it and/or modify + This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or + the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, @@ -15,105 +15,98 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - 02110-1301 USA -*/ + along with this program. If not, see . */ #ifndef SCAN_CODE_H_ # define SCAN_CODE_H_ # include "location.h" +# include "named-ref.h" struct symbol_list; /** - * \brief - * Keeps track of the maximum number of semantic values to the left of a - * handle (those referenced by \c $0, \c $-1, etc.) that are required by the - * semantic actions of this grammar. + * Keeps track of the maximum number of semantic values to the left of a handle + * (those referenced by $0, $-1, etc.) that are required by the semantic + * actions of this grammar. */ extern int max_left_semantic_context; /** - * \brief - * A code passage captured from the grammar file and possibly translated, - * and/or properties associated with such a code passage. - * \note - * - Don't break encapsulation by accessing the fields directly. Use the - * provided interface functions. + * A code passage captured from the grammar file and possibly translated, + * and/or properties associated with such a code passage. Don't break + * encapsulation by modifying the fields directly. Use the provided interface + * functions. */ typedef struct code_props { - /** - * \brief - * What kind of \c code_props this is. - * \sa - * - \c code_props_none_init - * - \c code_props_plain_init - * - \c code_props_symbol_action_init - * - \c code_props_rule_action_init - */ + /** Set by the init functions. */ enum { CODE_PROPS_NONE, CODE_PROPS_PLAIN, CODE_PROPS_SYMBOL_ACTION, CODE_PROPS_RULE_ACTION } kind; /** - * \brief - * The code passage contained within this \c code_props. - * \invariant - * - code_props::code = NULL iff - * code_props::kind = CODE_PROPS_NONE. + * \c NULL iff \c code_props::kind is \c CODE_PROPS_NONE. + * Memory is allocated in an obstack freed elsewhere. */ char const *code; - /** - * \brief - * The grammar file location of \c code_props::code. - * \invariant - * - \c code_props::location is undefined iff - * code_props::code = NULL. - */ + /** Undefined iff \c code_props::code is \c NULL. */ location location; + /** - * \brief - * The value returned by \c code_props_is_value_used for this - * \c code_props. + * \c false iff either: + * - \c code_props_translate_code has never previously been invoked for + * the \c code_props that would contain the code passage associated + * with \c self. (That \c code_props is not the same as this one if this + * one is for a RHS \c symbol_list node. Instead, it's the \c code_props + * for the LHS symbol of the same rule.) + * - \c code_props_translate_code has been invoked for that \c code_props, + * but the symbol value associated with this \c code_props was not + * referenced in the code passage. */ bool is_value_used; /** - * \brief - * The \c symbol_list node associated with this code passage. - * \invariant - * - code_props::rule != NULL iff \c code_props::kind is - * \c CODE_PROPS_RULE_ACTION. + * \c true iff this code is an action that is not to be deferred in + * a non-deterministic parser. */ + bool is_predicate; + + /** + * Whether this is actually used (i.e., not completely masked by + * other code props). */ + bool is_used; + + /** \c NULL iff \c code_props::kind is not \c CODE_PROPS_RULE_ACTION. */ struct symbol_list *rule; + + /* Named reference. */ + named_ref *named_ref; } code_props; /** * \pre * - self != NULL. * \post - * - \c self has been overwritten to contain no code. (However, \c self may - * still be conceptually associated with some passage of code contained - * elsewhere. Thus, a call on code_props_is_value_used (*self), - * for example, is still reasonable.) + * - \c self has been overwritten to contain no code. */ void code_props_none_init (code_props *self); -/** - * \brief A \c code_props initializer equivalent to \c code_props_none_init. - */ -#define CODE_PROPS_NONE_INIT \ - {CODE_PROPS_NONE, NULL, EMPTY_LOCATION_INIT, false, NULL} - -/** - * \brief - * A \c code_props initialized by \c CODE_PROPS_NONE_INIT with no further - * modification. - */ -extern code_props const code_props_none; +/** Equivalent to \c code_props_none_init. */ +# define CODE_PROPS_NONE_INIT \ + { \ + /* .kind = */ CODE_PROPS_NONE, \ + /* .code = */ NULL, \ + /* .location = */ EMPTY_LOCATION_INIT, \ + /* .is_value_used = */ false, \ + /* .is_predicate = */ false, \ + /* .is_used = */ false, \ + /* .rule = */ NULL, \ + /* .named_ref = */ NULL \ + } + +/** Initialized by \c CODE_PROPS_NONE_INIT with no further modification. */ +extern code_props code_props_none; /** * \pre @@ -124,7 +117,8 @@ extern code_props const code_props_none; * \post * - \c self has been overwritten to represent the specified plain code * passage. - * - \c self does not claim responsibility for the memory of \c code. + * - \c self will become invalid if the caller frees \c code before invoking + * \c code_props_translate_code on \c self. */ void code_props_plain_init (code_props *self, char const *code, location code_loc); @@ -134,11 +128,12 @@ void code_props_plain_init (code_props *self, char const *code, * - self != NULL. * - code != NULL. * - \c code is an untranslated code passage. The only Bison escapes it - * might contain are \c $$ and \c \@$, referring to a single symbol. + * might contain are $$ and \@$, referring to a single symbol. * - \c code was extracted from the grammar file at \c code_loc. * \post * - \c self has been overwritten to represent the specified symbol action. - * - \c self does not claim responsibility for the memory of \c code. + * - \c self will become invalid if the caller frees \c code before invoking + * \c code_props_translate_code on \c self. */ void code_props_symbol_action_init (code_props *self, char const *code, location code_loc); @@ -149,15 +144,20 @@ void code_props_symbol_action_init (code_props *self, char const *code, * - code != NULL. * - rule != NULL. * - \c code is the untranslated action of the rule for which \c rule is the - * LHS node. Thus, \c code possibly contains Bison escapes such as \c $$, - * \c $1, \c $2, etc referring to the values of the rule. + * LHS node. Thus, \c code possibly contains Bison escapes such as $$, $1, + * $2, etc referring to the values of the rule. + * - \c code was extracted from the grammar file at \c code_loc. * \post * - \c self has been overwritten to represent the specified rule action. - * - \c self does not claim responsibility for the memory of \c code or - * \c rule. + * - \c self does not claim responsibility for the memory of \c rule. + * - \c self will become invalid if: + * - The caller frees \c code before invoking \c code_props_translate_code + * on \c self. + * - The caller frees \c rule. */ void code_props_rule_action_init (code_props *self, char const *code, - location code_loc, struct symbol_list *rule); + location code_loc, struct symbol_list *rule, + named_ref *name, bool is_predicate); /** * \pre @@ -165,56 +165,20 @@ void code_props_rule_action_init (code_props *self, char const *code, * escapes, all grammar declarations have already been parsed as they may * affect warnings and complaints issued here. * \post - * - All M4 special symbols and Bison escapes have been translated in - * code_props_code_get (*self) iff - * code_props_code_get (*self \@pre) != NULL. + * - All M4-special symbols and Bison escapes have been translated in + * \c self->code. + * - self->code != self->code\@pre unless + * self->code\@pre = NULL. */ void code_props_translate_code (code_props *self); -/** - * \pre - * - None. - * \post - * - \c result = either: - * - The code passage contained with \c self. - * - \c NULL if none. - */ -char const *code_props_code_get (code_props const self); - -/** - * \pre - * - code_props_code_get (self) != NULL. - * \post - * - \c result = the grammar file location of - * code_props_code_get (self). - */ -location code_props_location_get (code_props const self); - -/** - * \pre - * - \c self was not previously initialized with \c code_props_plain_init. - * \post - * - \c result = either: - * - \c false if either: - * - \c code_props_translate_code has never previously been invoked for - * the \c code_props that would contain the code passage associated - * with \c self. (If \c self is for a RHS \c symbol_list node, that - * \c code_props is not \c self. Instead, it's the \c code_props for - * the LHS symbol of the same rule.) - * - \c code_props_translate_code has been invoked for that - * \c code_props, but the symbol value associated with \c self was not - * referenced in the code passage. - * - \c true otherwise. - */ -bool code_props_is_value_used (code_props const self); - /** * \pre * - None. * \post * - The dynamic memory allocated by the previous invocation of * \c code_props_translate_code (if any) was freed. The \c code_props - * instance for which that \c code_props_translate_code was invoked is now + * instance for which \c code_props_translate_code was invoked is now * invalid. */ void code_scanner_last_string_free (void); @@ -224,9 +188,8 @@ void code_scanner_last_string_free (void); * - None. * \post * - All dynamic memory allocated during invocations of - * \c code_props_translate_code (if any) has been freed. All - * \c code_props instances and all pointers returned by - * \c code_props_code_get may now be invalid. + * \c code_props_translate_code (if any) has been freed. All \c code_props + * instances may now be invalid. */ void code_scanner_free (void);