URL
https://opencores.org/ocsvn/openrisc/openrisc/trunk
Subversion Repositories openrisc
[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [gcc/] [gengtype-parse.c] - Rev 702
Go to most recent revision | Compare with Previous | Blame | View Log
/* Process source files and output type information. Copyright (C) 2006, 2007, 2010 Free Software Foundation, Inc. This file is part of GCC. GCC 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 3, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see <http://www.gnu.org/licenses/>. */ #ifdef GENERATOR_FILE #include "bconfig.h" #else #include "config.h" #endif #include "system.h" #include "gengtype.h" /* This is a simple recursive-descent parser which understands a subset of the C type grammar. Rule functions are suffixed _seq if they scan a sequence of items; _opt if they may consume zero tokens; _seqopt if both are true. The "consume_" prefix indicates that a sequence of tokens is parsed for syntactic correctness and then thrown away. */ /* Simple one-token lookahead mechanism. */ struct token { const char *value; int code; bool valid; }; static struct token T; /* Retrieve the code of the current token; if there is no current token, get the next one from the lexer. */ static inline int token (void) { if (!T.valid) { T.code = yylex (&T.value); T.valid = true; } return T.code; } /* Retrieve the value of the current token (if any) and mark it consumed. The next call to token() will get another token from the lexer. */ static inline const char * advance (void) { T.valid = false; return T.value; } /* Diagnostics. */ /* This array is indexed by the token code minus CHAR_TOKEN_OFFSET. */ static const char *const token_names[] = { "GTY", "typedef", "extern", "static", "union", "struct", "enum", "VEC", "DEF_VEC_[OP]", "DEF_VEC_I", "DEF_VEC_ALLOC_[IOP]", "...", "ptr_alias", "nested_ptr", "a param<N>_is option", "a number", "a scalar type", "an identifier", "a string constant", "a character constant", "an array declarator", }; /* This array is indexed by token code minus FIRST_TOKEN_WITH_VALUE. */ static const char *const token_value_format[] = { "%s", "'%s'", "'%s'", "'%s'", "'\"%s\"'", "\"'%s'\"", "'[%s]'", }; /* Produce a printable representation for a token defined by CODE and VALUE. This sometimes returns pointers into malloc memory and sometimes not, therefore it is unsafe to free the pointer it returns, so that memory is leaked. This does not matter, as this function is only used for diagnostics, and in a successful run of the program there will be none. */ static const char * print_token (int code, const char *value) { if (code < CHAR_TOKEN_OFFSET) return xasprintf ("'%c'", code); else if (code < FIRST_TOKEN_WITH_VALUE) return xasprintf ("'%s'", token_names[code - CHAR_TOKEN_OFFSET]); else if (!value) return token_names[code - CHAR_TOKEN_OFFSET]; /* don't quote these */ else return xasprintf (token_value_format[code - FIRST_TOKEN_WITH_VALUE], value); } /* Convenience wrapper around print_token which produces the printable representation of the current token. */ static inline const char * print_cur_token (void) { return print_token (T.code, T.value); } /* Report a parse error on the current line, with diagnostic MSG. Behaves as standard printf with respect to additional arguments and format escapes. */ static void ATTRIBUTE_PRINTF_1 parse_error (const char *msg, ...) { va_list ap; fprintf (stderr, "%s:%d: parse error: ", get_input_file_name (lexer_line.file), lexer_line.line); va_start (ap, msg); vfprintf (stderr, msg, ap); va_end (ap); fputc ('\n', stderr); hit_error = true; } /* If the next token does not have code T, report a parse error; otherwise return the token's value. */ static const char * require (int t) { int u = token (); const char *v = advance (); if (u != t) { parse_error ("expected %s, have %s", print_token (t, 0), print_token (u, v)); return 0; } return v; } /* If the next token does not have one of the codes T1 or T2, report a parse error; otherwise return the token's value. */ static const char * require2 (int t1, int t2) { int u = token (); const char *v = advance (); if (u != t1 && u != t2) { parse_error ("expected %s or %s, have %s", print_token (t1, 0), print_token (t2, 0), print_token (u, v)); return 0; } return v; } /* Near-terminals. */ /* C-style string constant concatenation: STRING+ Bare STRING should appear nowhere else in this file. */ static const char * string_seq (void) { const char *s1, *s2; size_t l1, l2; char *buf; s1 = require (STRING); if (s1 == 0) return ""; while (token () == STRING) { s2 = advance (); l1 = strlen (s1); l2 = strlen (s2); buf = XRESIZEVEC (char, CONST_CAST (char *, s1), l1 + l2 + 1); memcpy (buf + l1, s2, l2 + 1); XDELETE (CONST_CAST (char *, s2)); s1 = buf; } return s1; } /* typedef_name: either an ID, or VEC(x,y) which is translated to VEC_x_y. Use only where VEC(x,y) is legitimate, i.e. in positions where a typedef name may appear. */ static const char * typedef_name (void) { if (token () == VEC_TOKEN) { const char *c1, *c2, *r; advance (); require ('('); c1 = require2 (ID, SCALAR); require (','); c2 = require (ID); require (')'); r = concat ("VEC_", c1, "_", c2, (char *) 0); free (CONST_CAST (char *, c1)); free (CONST_CAST (char *, c2)); return r; } else return require (ID); } /* Absorb a sequence of tokens delimited by balanced ()[]{}. */ static void consume_balanced (int opener, int closer) { require (opener); for (;;) switch (token ()) { default: advance (); break; case '(': consume_balanced ('(', ')'); break; case '[': consume_balanced ('[', ']'); break; case '{': consume_balanced ('{', '}'); break; case '}': case ']': case ')': if (token () != closer) parse_error ("unbalanced delimiters - expected '%c', have '%c'", closer, token ()); advance (); return; case EOF_TOKEN: parse_error ("unexpected end of file within %c%c-delimited construct", opener, closer); return; } } /* Absorb a sequence of tokens, possibly including ()[]{}-delimited expressions, until we encounter a semicolon outside any such delimiters; absorb that too. If IMMEDIATE is true, it is an error if the semicolon is not the first token encountered. */ static void consume_until_semi (bool immediate) { if (immediate && token () != ';') require (';'); for (;;) switch (token ()) { case ';': advance (); return; default: advance (); break; case '(': consume_balanced ('(', ')'); break; case '[': consume_balanced ('[', ']'); break; case '{': consume_balanced ('{', '}'); break; case '}': case ']': case ')': parse_error ("unmatched '%c' while scanning for ';'", token ()); return; case EOF_TOKEN: parse_error ("unexpected end of file while scanning for ';'"); return; } } /* Absorb a sequence of tokens, possibly including ()[]{}-delimited expressions, until we encounter a comma or semicolon outside any such delimiters; absorb that too. If IMMEDIATE is true, it is an error if the comma or semicolon is not the first token encountered. Returns true if the loop ended with a comma. */ static bool consume_until_comma_or_semi (bool immediate) { if (immediate && token () != ',' && token () != ';') require2 (',', ';'); for (;;) switch (token ()) { case ',': advance (); return true; case ';': advance (); return false; default: advance (); break; case '(': consume_balanced ('(', ')'); break; case '[': consume_balanced ('[', ']'); break; case '{': consume_balanced ('{', '}'); break; case '}': case ']': case ')': parse_error ("unmatched '%s' while scanning for ',' or ';'", print_cur_token ()); return false; case EOF_TOKEN: parse_error ("unexpected end of file while scanning for ',' or ';'"); return false; } } /* GTY(()) option handling. */ static type_p type (options_p *optsp, bool nested); /* Optional parenthesized string: ('(' string_seq ')')? */ static options_p str_optvalue_opt (options_p prev) { const char *name = advance (); const char *value = ""; if (token () == '(') { advance (); value = string_seq (); require (')'); } return create_string_option (prev, name, value); } /* absdecl: type '*'* -- a vague approximation to what the C standard calls an abstract declarator. The only kinds that are actually used are those that are just a bare type and those that have trailing pointer-stars. Further kinds should be implemented if and when they become necessary. Used only within GTY(()) option values, therefore further GTY(()) tags within the type are invalid. Note that the return value has already been run through adjust_field_type. */ static type_p absdecl (void) { type_p ty; options_p opts; ty = type (&opts, true); while (token () == '*') { ty = create_pointer (ty); advance (); } if (opts) parse_error ("nested GTY(()) options are invalid"); return adjust_field_type (ty, 0); } /* Type-option: '(' absdecl ')' */ static options_p type_optvalue (options_p prev, const char *name) { type_p ty; require ('('); ty = absdecl (); require (')'); return create_type_option (prev, name, ty); } /* Nested pointer data: '(' type '*'* ',' string_seq ',' string_seq ')' */ static options_p nestedptr_optvalue (options_p prev) { type_p ty; const char *from, *to; require ('('); ty = absdecl (); require (','); to = string_seq (); require (','); from = string_seq (); require (')'); return create_nested_ptr_option (prev, ty, to, from); } /* One GTY(()) option: ID str_optvalue_opt | PTR_ALIAS type_optvalue | PARAM_IS type_optvalue | NESTED_PTR nestedptr_optvalue */ static options_p option (options_p prev) { switch (token ()) { case ID: return str_optvalue_opt (prev); case PTR_ALIAS: advance (); return type_optvalue (prev, "ptr_alias"); case PARAM_IS: return type_optvalue (prev, advance ()); case NESTED_PTR: advance (); return nestedptr_optvalue (prev); default: parse_error ("expected an option keyword, have %s", print_cur_token ()); advance (); return create_string_option (prev, "", ""); } } /* One comma-separated list of options. */ static options_p option_seq (void) { options_p o; o = option (0); while (token () == ',') { advance (); o = option (o); } return o; } /* GTY marker: 'GTY' '(' '(' option_seq? ')' ')' */ static options_p gtymarker (void) { options_p result = 0; require (GTY_TOKEN); require ('('); require ('('); if (token () != ')') result = option_seq (); require (')'); require (')'); return result; } /* Optional GTY marker. */ static options_p gtymarker_opt (void) { if (token () != GTY_TOKEN) return 0; return gtymarker (); } /* Declarators. The logic here is largely lifted from c-parser.c. Note that we do not have to process abstract declarators, which can appear only in parameter type lists or casts (but see absdecl, above). Also, type qualifiers are thrown out in gengtype-lex.l so we don't have to do it. */ /* array_and_function_declarators_opt: \epsilon array_and_function_declarators_opt ARRAY array_and_function_declarators_opt '(' ... ')' where '...' indicates stuff we ignore except insofar as grouping symbols ()[]{} must balance. Subroutine of direct_declarator - do not use elsewhere. */ static type_p array_and_function_declarators_opt (type_p ty) { if (token () == ARRAY) { const char *array = advance (); return create_array (array_and_function_declarators_opt (ty), array); } else if (token () == '(') { /* We don't need exact types for functions. */ consume_balanced ('(', ')'); array_and_function_declarators_opt (ty); return create_scalar_type ("function type"); } else return ty; } static type_p inner_declarator (type_p, const char **, options_p *); /* direct_declarator: '(' inner_declarator ')' gtymarker_opt ID array_and_function_declarators_opt Subroutine of declarator, mutually recursive with inner_declarator; do not use elsewhere. */ static type_p direct_declarator (type_p ty, const char **namep, options_p *optsp) { /* The first token in a direct-declarator must be an ID, a GTY marker, or an open parenthesis. */ switch (token ()) { case GTY_TOKEN: *optsp = gtymarker (); /* fall through */ case ID: *namep = require (ID); break; case '(': advance (); ty = inner_declarator (ty, namep, optsp); require (')'); break; default: parse_error ("expected '(', 'GTY', or an identifier, have %s", print_cur_token ()); /* Do _not_ advance if what we have is a close squiggle brace, as we will get much better error recovery that way. */ if (token () != '}') advance (); return 0; } return array_and_function_declarators_opt (ty); } /* The difference between inner_declarator and declarator is in the handling of stars. Consider this declaration: char * (*pfc) (void) It declares a pointer to a function that takes no arguments and returns a char*. To construct the correct type for this declaration, the star outside the parentheses must be processed _before_ the function type, the star inside the parentheses must be processed _after_ the function type. To accomplish this, declarator() creates pointers before recursing (it is actually coded as a while loop), whereas inner_declarator() recurses before creating pointers. */ /* inner_declarator: '*' inner_declarator direct_declarator Mutually recursive subroutine of direct_declarator; do not use elsewhere. */ static type_p inner_declarator (type_p ty, const char **namep, options_p *optsp) { if (token () == '*') { type_p inner; advance (); inner = inner_declarator (ty, namep, optsp); if (inner == 0) return 0; else return create_pointer (ty); } else return direct_declarator (ty, namep, optsp); } /* declarator: '*'+ direct_declarator This is the sole public interface to this part of the grammar. Arguments are the type known so far, a pointer to where the name may be stored, and a pointer to where GTY options may be stored. Returns the final type. */ static type_p declarator (type_p ty, const char **namep, options_p *optsp) { *namep = 0; *optsp = 0; while (token () == '*') { advance (); ty = create_pointer (ty); } return direct_declarator (ty, namep, optsp); } /* Types and declarations. */ /* Structure field(s) declaration: ( type bitfield ';' | type declarator bitfield? ( ',' declarator bitfield? )+ ';' )+ Knows that such declarations must end with a close brace (or, erroneously, at EOF). */ static pair_p struct_field_seq (void) { pair_p f = 0; type_p ty, dty; options_p opts, dopts; const char *name; bool another; do { ty = type (&opts, true); /* Another piece of the IFCVT_EXTRA_FIELDS special case, see type(). */ if (!ty && token () == '}') break; if (!ty || token () == ':') { consume_until_semi (false); continue; } do { dty = declarator (ty, &name, &dopts); /* There could be any number of weird things after the declarator, notably bitfield declarations and __attribute__s. If this function returns true, the last thing was a comma, so we have more than one declarator paired with the current type. */ another = consume_until_comma_or_semi (false); if (!dty) continue; if (opts && dopts) parse_error ("two GTY(()) options for field %s", name); if (opts && !dopts) dopts = opts; f = create_field_at (f, dty, name, dopts, &lexer_line); } while (another); } while (token () != '}' && token () != EOF_TOKEN); return nreverse_pairs (f); } /* This is called type(), but what it parses (sort of) is what C calls declaration-specifiers and specifier-qualifier-list: SCALAR | ID // typedef | (STRUCT|UNION) ID? gtymarker? ( '{' gtymarker? struct_field_seq '}' )? | ENUM ID ( '{' ... '}' )? Returns a partial type; under some conditions (notably "struct foo GTY((...)) thing;") it may write an options structure to *OPTSP. */ static type_p type (options_p *optsp, bool nested) { const char *s; *optsp = 0; switch (token ()) { case SCALAR: s = advance (); return create_scalar_type (s); case ID: case VEC_TOKEN: s = typedef_name (); return resolve_typedef (s, &lexer_line); case STRUCT: case UNION: { options_p opts = 0; /* GTY annotations follow attribute syntax GTY_BEFORE_ID is for union/struct declarations GTY_AFTER_ID is for variable declarations. */ enum { NO_GTY, GTY_BEFORE_ID, GTY_AFTER_ID } is_gty = NO_GTY; bool is_union = (token () == UNION); advance (); /* Top-level structures that are not explicitly tagged GTY(()) are treated as mere forward declarations. This is because there are a lot of structures that we don't need to know about, and some of those have weird macro stuff in them that we can't handle. */ if (nested || token () == GTY_TOKEN) { is_gty = GTY_BEFORE_ID; opts = gtymarker_opt (); } if (token () == ID) s = advance (); else s = xasprintf ("anonymous:%s:%d", get_input_file_name (lexer_line.file), lexer_line.line); /* Unfortunately above GTY_TOKEN check does not capture the typedef struct_type GTY case. */ if (token () == GTY_TOKEN) { is_gty = GTY_AFTER_ID; opts = gtymarker_opt (); } if (is_gty) { if (token () == '{') { pair_p fields; if (is_gty == GTY_AFTER_ID) parse_error ("GTY must be specified before identifier"); advance (); fields = struct_field_seq (); require ('}'); return new_structure (s, is_union, &lexer_line, fields, opts); } } else if (token () == '{') consume_balanced ('{', '}'); if (opts) *optsp = opts; return find_structure (s, is_union); } case ENUM: advance (); if (token () == ID) s = advance (); else s = xasprintf ("anonymous:%s:%d", get_input_file_name (lexer_line.file), lexer_line.line); if (token () == '{') consume_balanced ('{', '}'); return create_scalar_type (s); default: parse_error ("expected a type specifier, have %s", print_cur_token ()); advance (); return create_scalar_type ("erroneous type"); } } /* Top level constructs. */ /* Dispatch declarations beginning with 'typedef'. */ static void typedef_decl (void) { type_p ty, dty; const char *name; options_p opts; bool another; gcc_assert (token () == TYPEDEF); advance (); ty = type (&opts, false); if (!ty) return; if (opts) parse_error ("GTY((...)) cannot be applied to a typedef"); do { dty = declarator (ty, &name, &opts); if (opts) parse_error ("GTY((...)) cannot be applied to a typedef"); /* Yet another place where we could have junk (notably attributes) after the declarator. */ another = consume_until_comma_or_semi (false); if (dty) do_typedef (name, dty, &lexer_line); } while (another); } /* Structure definition: type() does all the work. */ static void struct_or_union (void) { options_p dummy; type (&dummy, false); /* There may be junk after the type: notably, we cannot currently distinguish 'struct foo *function(prototype);' from 'struct foo;' ... we could call declarator(), but it's a waste of time at present. Instead, just eat whatever token is currently lookahead and go back to lexical skipping mode. */ advance (); } /* GC root declaration: (extern|static) gtymarker? type ID array_declarators_opt (';'|'=') If the gtymarker is not present, we ignore the rest of the declaration. */ static void extern_or_static (void) { options_p opts, opts2, dopts; type_p ty, dty; const char *name; require2 (EXTERN, STATIC); if (token () != GTY_TOKEN) { advance (); return; } opts = gtymarker (); ty = type (&opts2, true); /* if we get here, it's got a GTY(()) */ dty = declarator (ty, &name, &dopts); if ((opts && dopts) || (opts && opts2) || (opts2 && dopts)) parse_error ("GTY((...)) specified more than once for %s", name); else if (opts2) opts = opts2; else if (dopts) opts = dopts; if (dty) { note_variable (name, adjust_field_type (dty, opts), opts, &lexer_line); require2 (';', '='); } } /* Definition of a generic VEC structure: 'DEF_VEC_[IPO]' '(' id ')' ';' Scalar VECs require slightly different treatment than otherwise - that's handled in note_def_vec, we just pass it along.*/ static void def_vec (void) { bool is_scalar = (token () == DEFVEC_I); const char *type; require2 (DEFVEC_OP, DEFVEC_I); require ('('); type = require2 (ID, SCALAR); require (')'); require (';'); if (!type) return; note_def_vec (type, is_scalar, &lexer_line); note_def_vec_alloc (type, "none", &lexer_line); } /* Definition of an allocation strategy for a VEC structure: 'DEF_VEC_ALLOC_[IPO]' '(' id ',' id ')' ';' For purposes of gengtype, this just declares a wrapper structure. */ static void def_vec_alloc (void) { const char *type, *astrat; require (DEFVEC_ALLOC); require ('('); type = require2 (ID, SCALAR); require (','); astrat = require (ID); require (')'); require (';'); if (!type || !astrat) return; note_def_vec_alloc (type, astrat, &lexer_line); } /* Parse the file FNAME for GC-relevant declarations and definitions. This is the only entry point to this file. */ void parse_file (const char *fname) { yybegin (fname); for (;;) { switch (token ()) { case EXTERN: case STATIC: extern_or_static (); break; case STRUCT: case UNION: struct_or_union (); break; case TYPEDEF: typedef_decl (); break; case DEFVEC_OP: case DEFVEC_I: def_vec (); break; case DEFVEC_ALLOC: def_vec_alloc (); break; case EOF_TOKEN: goto eof; default: parse_error ("unexpected top level token, %s", print_cur_token ()); goto eof; } lexer_toplevel_done = 1; } eof: advance (); yyend (); }
Go to most recent revision | Compare with Previous | Blame | View Log