X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/3d38c03a861993c3c8e3c05dd76a3881601e10c2..927b425baae16fc1d50e092b78b944e281b521f6:/src/parse-gram.y?ds=sidebyside diff --git a/src/parse-gram.y b/src/parse-gram.y index a6d8ec70..11cd489e 100644 --- a/src/parse-gram.y +++ b/src/parse-gram.y @@ -1,5 +1,6 @@ -/* Bison Grammar Parser -*- C -*- - Copyright (C) 2002 Free Software Foundation, Inc. +%{/* Bison Grammar Parser -*- C -*- + + Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -15,156 +16,191 @@ 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., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + 02110-1301 USA */ - -%debug -%defines -%locations -%pure-parser -// %error-verbose -%defines -%name-prefix="gram_" - -%{ +#include #include "system.h" + #include "complain.h" -#include "muscle_tab.h" +#include "conflicts.h" #include "files.h" #include "getargs.h" -#include "output.h" -#include "symlist.h" #include "gram.h" +#include "muscle_tab.h" +#include "output.h" +#include "quotearg.h" #include "reader.h" -#include "conflicts.h" +#include "symlist.h" +#include "strverscmp.h" + +#define YYLLOC_DEFAULT(Current, Rhs, N) (Current) = lloc_default (Rhs, N) +static YYLTYPE lloc_default (YYLTYPE const *, int); -/* Produce verbose parse errors. */ -#define YYERROR_VERBOSE 1 -#define YYLLOC_DEFAULT(Current, Rhs, N) \ -do { \ - if (N) \ - { \ - Current.first_column = Rhs[1].first_column; \ - Current.first_line = Rhs[1].first_line; \ - Current.last_column = Rhs[N].last_column; \ - Current.last_line = Rhs[N].last_line; \ - } \ - else \ - { \ - Current = Rhs[0]; \ - } \ -} while (0) - -/* Pass the control structure to YYPARSE and YYLEX. */ -#define YYPARSE_PARAM gram_control -#define YYLEX_PARAM gram_control -/* YYPARSE receives GRAM_CONTROL as a void *. Provide a - correctly typed access to it. */ -#define yycontrol ((gram_control_t *) gram_control) - -/* Request detailed parse error messages, and pass them to GRAM_ERROR. - FIXME: depends on the undocumented availability of YYLLOC.t */ +#define YY_LOCATION_PRINT(File, Loc) \ + location_print (File, Loc) + +static void version_check (location const *loc, char const *version); + +/* Request detailed syntax error messages, and pass them to GRAM_ERROR. + FIXME: depends on the undocumented availability of YYLLOC. */ #undef yyerror #define yyerror(Msg) \ - gram_error (&yylloc, Msg) - -#define YYPRINT(File, Type, Value) \ - yyprint (File, Type, &Value) -static void yyprint (FILE *file, int type, const yystype *value); - -symbol_class current_class = unknown_sym; -char *current_type = 0; -symbol_t *current_lhs; -location_t current_lhs_location; -assoc_t current_assoc; -int current_prec = 0; -braced_code_t current_braced_code = action_braced_code; + gram_error (&yylloc, Msg) +static void gram_error (location const *, char const *); + +static void add_param (char const *, char *, location); + +static symbol_class current_class = unknown_sym; +static uniqstr current_type = 0; +static symbol *current_lhs; +static location current_lhs_location; +static int current_prec = 0; + +#ifdef UINT_FAST8_MAX +# define YYTYPE_UINT8 uint_fast8_t +#endif +#ifdef INT_FAST8_MAX +# define YYTYPE_INT8 int_fast8_t +#endif +#ifdef UINT_FAST16_MAX +# define YYTYPE_UINT16 uint_fast16_t +#endif +#ifdef INT_FAST16_MAX +# define YYTYPE_INT16 int_fast16_t +#endif %} +%debug +%verbose +%defines +%locations +%pure-parser +%error-verbose +%defines +%name-prefix="gram_" + +%initial-action +{ + /* Bison's grammar can initial empty locations, hence a default + location is needed. */ + @$.start.file = @$.end.file = current_file; + @$.start.line = @$.end.line = 1; + @$.start.column = @$.end.column = 0; +} /* Only NUMBERS have a value. */ %union { - symbol_t *symbol; - symbol_list_t *list; + symbol *symbol; + symbol_list *list; int integer; - char *string; - assoc_t assoc; + char *chars; + assoc assoc; + uniqstr uniqstr; }; /* Define the tokens together with their human representation. */ %token GRAM_EOF 0 "end of file" %token STRING "string" -%token CHARACTER "character" %token INT "integer" %token PERCENT_TOKEN "%token" %token PERCENT_NTERM "%nterm" %token PERCENT_TYPE "%type" -%token PERCENT_DESTRUCTOR "%destructor" -%token PERCENT_PRINTER "%printer" +%token PERCENT_DESTRUCTOR "%destructor {...}" +%token PERCENT_PRINTER "%printer {...}" -%token PERCENT_UNION "%union" +%token PERCENT_UNION "%union {...}" %token PERCENT_LEFT "%left" %token PERCENT_RIGHT "%right" %token PERCENT_NONASSOC "%nonassoc" -%token PERCENT_EXPECT "%expect" -%token PERCENT_START "%start" %token PERCENT_PREC "%prec" %token PERCENT_DPREC "%dprec" %token PERCENT_MERGE "%merge" -%token PERCENT_VERBOSE "%verbose" -%token PERCENT_ERROR_VERBOSE "%error-verbose" - -%token PERCENT_OUTPUT "%output" -%token PERCENT_FILE_PREFIX "%file-prefix" -%token PERCENT_NAME_PREFIX "%name-prefix" - -%token PERCENT_DEFINE "%define" -%token PERCENT_PURE_PARSER "%pure-parser" -%token PERCENT_GLR_PARSER "%glr-parser" -%token PERCENT_DEFINES "%defines" -%token PERCENT_YACC "%yacc" - -%token PERCENT_DEBUG "%debug" -%token PERCENT_LOCATIONS "%locations" -%token PERCENT_NO_LINES "%no-lines" -%token PERCENT_SKELETON "%skeleton" -%token PERCENT_TOKEN_TABLE "%token-table" +/*----------------------. +| Global Declarations. | +`----------------------*/ + +%token + PERCENT_DEBUG "%debug" + PERCENT_DEFAULT_PREC "%default-prec" + PERCENT_DEFINE "%define" + PERCENT_DEFINES "%defines" + PERCENT_ERROR_VERBOSE "%error-verbose" + PERCENT_EXPECT "%expect" + PERCENT_EXPECT_RR "%expect-rr" + PERCENT_FILE_PREFIX "%file-prefix" + PERCENT_GLR_PARSER "%glr-parser" + PERCENT_INITIAL_ACTION "%initial-action {...}" + PERCENT_LEX_PARAM "%lex-param {...}" + PERCENT_LOCATIONS "%locations" + PERCENT_NAME_PREFIX "%name-prefix" + PERCENT_NO_DEFAULT_PREC "%no-default-prec" + PERCENT_NO_LINES "%no-lines" + PERCENT_NONDETERMINISTIC_PARSER + "%nondeterministic-parser" + PERCENT_OUTPUT "%output" + PERCENT_PARSE_PARAM "%parse-param {...}" + PERCENT_PURE_PARSER "%pure-parser" + PERCENT_REQUIRE "%require" + PERCENT_SKELETON "%skeleton" + PERCENT_START "%start" + PERCENT_TOKEN_TABLE "%token-table" + PERCENT_VERBOSE "%verbose" + PERCENT_YACC "%yacc" +; %token TYPE "type" %token EQUAL "=" %token SEMICOLON ";" -%token COLON ":" %token PIPE "|" %token ID "identifier" +%token ID_COLON "identifier:" %token PERCENT_PERCENT "%%" %token PROLOGUE "%{...%}" %token EPILOGUE "epilogue" %token BRACED_CODE "{...}" -%type CHARACTER TYPE STRING string_content - BRACED_CODE PROLOGUE EPILOGUE epilogue.opt action +%type STRING string_content + "%destructor {...}" + "%initial-action {...}" + "%lex-param {...}" + "%parse-param {...}" + "%printer {...}" + "%union {...}" + PROLOGUE EPILOGUE +%printer { fprintf (stderr, "\"%s\"", $$); } + STRING string_content +%printer { fprintf (stderr, "{\n%s\n}", $$); } + "%destructor {...}" + "%initial-action {...}" + "%lex-param {...}" + "%parse-param {...}" + "%printer {...}" + "%union {...}" + PROLOGUE EPILOGUE +%type TYPE +%printer { fprintf (stderr, "<%s>", $$); } TYPE %type INT +%printer { fprintf (stderr, "%d", $$); } INT %type ID symbol string_as_id +%printer { fprintf (stderr, "%s", $$->tag); } ID symbol string_as_id +%type ID_COLON +%printer { fprintf (stderr, "%s:", $$->tag); } ID_COLON %type precedence_declarator %type symbols.1 %% input: declarations "%%" grammar epilogue.opt - { - yycontrol->errcode = 0; - epilogue_set ($4, @4); - } ; @@ -174,28 +210,47 @@ input: declarations: /* Nothing */ -| declarations declaration semi_colon.opt +| declarations declaration ; declaration: grammar_declaration | PROLOGUE { prologue_augment ($1, @1); } -| "%debug" { debug_flag = 1; } +| "%debug" { debug_flag = true; } +| "%define" string_content + { + static char one[] = "1"; + muscle_insert ($2, one); + } | "%define" string_content string_content { muscle_insert ($2, $3); } -| "%defines" { defines_flag = 1; } -| "%error-verbose" { error_verbose = 1; } -| "%expect" INT { expected_conflicts = $2; } +| "%defines" { defines_flag = true; } +| "%error-verbose" { error_verbose = true; } +| "%expect" INT { expected_sr_conflicts = $2; } +| "%expect-rr" INT { expected_rr_conflicts = $2; } | "%file-prefix" "=" string_content { spec_file_prefix = $3; } -| "%locations" { locations_flag = 1; } +| "%glr-parser" + { + nondeterministic_parser = true; + glr_parser = true; + } +| "%initial-action {...}" + { + muscle_code_grow ("initial_action", $1, @1); + } +| "%lex-param {...}" { add_param ("lex_param", $1, @1); } +| "%locations" { locations_flag = true; } | "%name-prefix" "=" string_content { spec_name_prefix = $3; } -| "%no-lines" { no_lines_flag = 1; } +| "%no-lines" { no_lines_flag = true; } +| "%nondeterministic-parser" { nondeterministic_parser = true; } | "%output" "=" string_content { spec_outfile = $3; } -| "%pure-parser" { pure_parser = 1; } -| "%glr-parser" { glr_parser = 1; } +| "%parse-param {...}" { add_param ("parse_param", $1, @1); } +| "%pure-parser" { pure_parser = true; } +| "%require" string_content { version_check (&@2, $2); } | "%skeleton" string_content { skeleton = $2; } -| "%token-table" { token_table_flag = 1; } -| "%verbose" { report_flag = 1; } -| "%yacc" { yacc_flag = 1; } +| "%token-table" { token_table_flag = true; } +| "%verbose" { report_flag = report_states; } +| "%yacc" { yacc_flag = true; } +| /*FIXME: Err? What is this horror doing here? */ ";" ; grammar_declaration: @@ -205,31 +260,43 @@ grammar_declaration: { grammar_start_symbol_set ($2, @2); } -| "%union" BRACED_CODE +| "%union {...}" + { + char const *body = $1; + + if (typed) + { + /* Concatenate the union bodies, turning the first one's + trailing '}' into '\n', and omitting the second one's '{'. */ + char *code = muscle_find ("stype"); + code[strlen (code) - 1] = '\n'; + body++; + } + + typed = true; + muscle_code_grow ("stype", body, @1); + } +| "%destructor {...}" symbols.1 { - typed = 1; - MUSCLE_INSERT_INT ("stype_line", @2.first_line); - muscle_insert ("stype", $2); + symbol_list *list; + for (list = $2; list; list = list->next) + symbol_destructor_set (list->sym, $1, @1); + symbol_list_free ($2); } -| "%destructor" - { current_braced_code = destructor_braced_code; } - BRACED_CODE symbols.1 +| "%printer {...}" symbols.1 { - symbol_list_t *list; - for (list = $4; list; list = list->next) - symbol_destructor_set (list->sym, $3, @3); - symbol_list_free ($4); - current_braced_code = action_braced_code; + symbol_list *list; + for (list = $2; list; list = list->next) + symbol_printer_set (list->sym, $1, @1); + symbol_list_free ($2); } -| "%printer" - { current_braced_code = printer_braced_code; } - BRACED_CODE symbols.1 +| "%default-prec" { - symbol_list_t *list; - for (list = $4; list; list = list->next) - symbol_printer_set (list->sym, $3, list->location); - symbol_list_free ($4); - current_braced_code = action_braced_code; + default_prec = true; + } +| "%no-default-prec" + { + default_prec = false; } ; @@ -246,7 +313,7 @@ symbol_declaration: } | "%type" TYPE symbols.1 { - symbol_list_t *list; + symbol_list *list; for (list = $3; list; list = list->next) symbol_type_set (list->sym, $2, @2); symbol_list_free ($3); @@ -256,7 +323,7 @@ symbol_declaration: precedence_declaration: precedence_declarator type.opt symbols.1 { - symbol_list_t *list; + symbol_list *list; ++current_prec; for (list = $3; list; list = list->next) { @@ -275,7 +342,7 @@ precedence_declarator: ; type.opt: - /* Nothing. */ { current_type = NULL;} + /* Nothing. */ { current_type = NULL; } | TYPE { current_type = $1; } ; @@ -294,24 +361,24 @@ symbol_def: } | ID { - symbol_class_set ($1, current_class, @1); + symbol_class_set ($1, current_class, @1, true); symbol_type_set ($1, current_type, @1); } | ID INT { - symbol_class_set ($1, current_class, @1); + symbol_class_set ($1, current_class, @1, true); symbol_type_set ($1, current_type, @1); symbol_user_token_number_set ($1, $2, @2); } | ID string_as_id { - symbol_class_set ($1, current_class, @1); + symbol_class_set ($1, current_class, @1, true); symbol_type_set ($1, current_type, @1); symbol_make_alias ($1, $2, @$); } | ID INT string_as_id { - symbol_class_set ($1, current_class, @1); + symbol_class_set ($1, current_class, @1, true); symbol_type_set ($1, current_type, @1); symbol_user_token_number_set ($1, $2, @2); symbol_make_alias ($1, $3, @$); @@ -321,9 +388,7 @@ symbol_def: /* One or more symbol definitions. */ symbol_defs.1: symbol_def - {;} | symbol_defs.1 symbol_def - {;} ; @@ -337,15 +402,10 @@ grammar: ; /* As a Bison extension, one can use the grammar declarations in the - body of the grammar. But to remain LALR(1), they must be ended - with a semi-colon. */ + body of the grammar. */ rules_or_grammar_declaration: rules | grammar_declaration ";" - { - if (yacc_flag) - complain_at (@$, _("POSIX forbids declarations in the grammar")); - } | error ";" { yyerrok; @@ -353,22 +413,21 @@ rules_or_grammar_declaration: ; rules: - ID ":" { current_lhs = $1; current_lhs_location = @1; } rhses.1 ";" - {;} + ID_COLON { current_lhs = $1; current_lhs_location = @1; } rhses.1 ; rhses.1: - rhs { grammar_rule_end (@1); } -| rhses.1 "|" rhs { grammar_rule_end (@3); } + rhs { grammar_current_rule_end (@1); } +| rhses.1 "|" rhs { grammar_current_rule_end (@3); } +| rhses.1 ";" ; rhs: /* Nothing. */ - { grammar_rule_begin (current_lhs, current_lhs_location); } + { grammar_current_rule_begin (current_lhs, current_lhs_location); } | rhs symbol { grammar_current_rule_symbol_append ($2, @2); } | rhs action - { grammar_current_rule_action_append ($2, @2); } | rhs "%prec" symbol { grammar_current_rule_prec_set ($3, @3); } | rhs "%dprec" INT @@ -380,89 +439,153 @@ rhs: symbol: ID { $$ = $1; } | string_as_id { $$ = $1; } -| CHARACTER { $$ = symbol_get ($1, @1); } ; +/* Handle the semantics of an action specially, with a mid-rule + action, so that grammar_current_rule_action_append is invoked + immediately after the braced code is read by the scanner. + + This implementation relies on the LALR(1) parsing algorithm. + If grammar_current_rule_action_append were executed in a normal + action for this rule, then when the input grammar contains two + successive actions, the scanner would have to read both actions + before reducing this rule. That wouldn't work, since the scanner + relies on all preceding input actions being processed by + grammar_current_rule_action_append before it scans the next + action. */ action: + { grammar_current_rule_action_append (last_string, last_braced_code_loc); } BRACED_CODE - { $$ = $1; } ; -/* A string used as an ID: we have to keep the quotes. */ +/* A string used as an ID: quote it. */ string_as_id: STRING { - $$ = symbol_get ($1, @1); - symbol_class_set ($$, token_sym, @1); + $$ = symbol_get (quotearg_style (c_quoting_style, $1), @1); + symbol_class_set ($$, token_sym, @1, false); } ; -/* A string used for its contents. Strip the quotes. */ +/* A string used for its contents. Don't quote it. */ string_content: STRING - { - $$ = $1 + 1; - $$[strlen ($$) - 1] = '\0'; - }; + { $$ = $1; } +; epilogue.opt: /* Nothing. */ - { - $$ = xstrdup (""); - } | "%%" EPILOGUE { - $$ = $2; + muscle_code_grow ("epilogue", $2, @2); + scanner_last_string_free (); } ; -semi_colon.opt: - /* Nothing. */ -| ";" -; %% -/*------------------------------------------------------------------. -| When debugging the parser, display tokens' locations and values. | -`------------------------------------------------------------------*/ + + +/* Return the location of the left-hand side of a rule whose + right-hand side is RHS[1] ... RHS[N]. Ignore empty nonterminals in + the right-hand side, and return an empty location equal to the end + boundary of RHS[0] if the right-hand side is empty. */ + +static YYLTYPE +lloc_default (YYLTYPE const *rhs, int n) +{ + int i; + YYLTYPE loc; + + /* SGI MIPSpro 7.4.1m miscompiles "loc.start = loc.end = rhs[n].end;". + The bug is fixed in 7.4.2m, but play it safe for now. */ + loc.start = rhs[n].end; + loc.end = rhs[n].end; + + /* Ignore empty nonterminals the start of the the right-hand side. + Do not bother to ignore them at the end of the right-hand side, + since empty nonterminals have the same end as their predecessors. */ + for (i = 1; i <= n; i++) + if (! equal_boundaries (rhs[i].start, rhs[i].end)) + { + loc.start = rhs[i].start; + break; + } + + return loc; +} + + +/* Add a lex-param or a parse-param (depending on TYPE) with + declaration DECL and location LOC. */ static void -yyprint (FILE *file, - int type, const yystype *value) +add_param (char const *type, char *decl, location loc) { - fputc (' ', file); - switch (type) + static char const alphanum[26 + 26 + 1 + 10] = + "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "_" + "0123456789"; + char const *name_start = NULL; + char *p; + + /* Stop on last actual character. */ + for (p = decl; p[1]; p++) + if ((p == decl + || ! memchr (alphanum, p[-1], sizeof alphanum)) + && memchr (alphanum, p[0], sizeof alphanum - 10)) + name_start = p; + + /* Strip the surrounding '{' and '}', and any blanks just inside + the braces. */ + while (*--p == ' ' || *p == '\t') + continue; + p[1] = '\0'; + while (*++decl == ' ' || *decl == '\t') + continue; + + if (! name_start) + complain_at (loc, _("missing identifier in parameter declaration")); + else { - case CHARACTER: - fprintf (file, " = '%s'", value->string); - break; - - case ID: - fprintf (file, " = %s", value->symbol->tag); - break; - - case INT: - fprintf (file, " = %d", value->integer); - break; - - case STRING: - fprintf (file, " = \"%s\"", value->string); - break; - - case TYPE: - fprintf (file, " = <%s>", value->string); - break; - - case BRACED_CODE: - case PROLOGUE: - case EPILOGUE: - fprintf (file, " = {{ %s }}", value->string); - break; + char *name; + size_t name_len; + + for (name_len = 1; + memchr (alphanum, name_start[name_len], sizeof alphanum); + name_len++) + continue; + + name = xmalloc (name_len + 1); + memcpy (name, name_start, name_len); + name[name_len] = '\0'; + muscle_pair_list_grow (type, decl, name); + free (name); } + + scanner_last_string_free (); +} + +static void +version_check (location const *loc, char const *version) +{ + if (strverscmp (version, PACKAGE_VERSION) > 0) + { + complain_at (*loc, "require bison %s, but have %s", + version, PACKAGE_VERSION); + exit (63); + } +} + +static void +gram_error (location const *loc, char const *msg) +{ + complain_at (*loc, "%s", msg); } -void -gram_error (location_t *yylloc, const char *msg) +char const * +token_name (int type) { - complain_at (*yylloc, "%s", msg); + return yytname[YYTRANSLATE (type)]; }