1223 lines
28 KiB
Plaintext
1223 lines
28 KiB
Plaintext
/* Parse C expressions for CCCP.
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Copyright (C) 1987, 92, 94-98, 1999 Free Software Foundation.
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This program is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation; either version 2, or (at your option) any
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later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA.
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In other words, you are welcome to use, share and improve this program.
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You are forbidden to forbid anyone else to use, share and improve
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what you give them. Help stamp out software-hoarding!
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Adapted from expread.y of GDB by Paul Rubin, July 1986. */
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/* Parse a C expression from text in a string */
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%{
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#include "config.h"
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#include "system.h"
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#include "intl.h"
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#include <setjmp.h>
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/* #define YYDEBUG 1 */
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#ifdef MULTIBYTE_CHARS
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#include "mbchar.h"
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#include <locale.h>
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#endif /* MULTIBYTE_CHARS */
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typedef unsigned char U_CHAR;
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/* This is used for communicating lists of keywords with cccp.c. */
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struct arglist {
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struct arglist *next;
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U_CHAR *name;
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int length;
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int argno;
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};
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HOST_WIDEST_INT parse_c_expression PROTO((char *, int));
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static int yylex PROTO((void));
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static void yyerror PVPROTO((const char *, ...))
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ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
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static HOST_WIDEST_INT expression_value;
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#ifdef TEST_EXP_READER
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static int expression_signedp;
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#endif
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static jmp_buf parse_return_error;
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/* Nonzero means count most punctuation as part of a name. */
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static int keyword_parsing = 0;
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/* Nonzero means do not evaluate this expression.
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This is a count, since unevaluated expressions can nest. */
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static int skip_evaluation;
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/* Nonzero means warn if undefined identifiers are evaluated. */
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static int warn_undef;
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/* some external tables of character types */
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extern unsigned char is_idstart[], is_idchar[], is_space[];
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/* Flag for -pedantic. */
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extern int pedantic;
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/* Flag for -traditional. */
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extern int traditional;
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/* Flag for -lang-c89. */
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extern int c89;
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#ifndef CHAR_TYPE_SIZE
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#define CHAR_TYPE_SIZE BITS_PER_UNIT
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#endif
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#ifndef INT_TYPE_SIZE
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#define INT_TYPE_SIZE BITS_PER_WORD
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#endif
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#ifndef LONG_TYPE_SIZE
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#define LONG_TYPE_SIZE BITS_PER_WORD
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#endif
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#ifndef WCHAR_TYPE_SIZE
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#define WCHAR_TYPE_SIZE INT_TYPE_SIZE
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#endif
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#ifndef MAX_CHAR_TYPE_SIZE
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#define MAX_CHAR_TYPE_SIZE CHAR_TYPE_SIZE
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#endif
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#ifndef MAX_INT_TYPE_SIZE
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#define MAX_INT_TYPE_SIZE INT_TYPE_SIZE
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#endif
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#ifndef MAX_LONG_TYPE_SIZE
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#define MAX_LONG_TYPE_SIZE LONG_TYPE_SIZE
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#endif
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#ifndef MAX_WCHAR_TYPE_SIZE
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#define MAX_WCHAR_TYPE_SIZE WCHAR_TYPE_SIZE
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#endif
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#define MAX_CHAR_TYPE_MASK (MAX_CHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \
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? (~ (~ (HOST_WIDEST_INT) 0 << MAX_CHAR_TYPE_SIZE)) \
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: ~ (HOST_WIDEST_INT) 0)
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#define MAX_WCHAR_TYPE_MASK (MAX_WCHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \
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? ~ (~ (HOST_WIDEST_INT) 0 << MAX_WCHAR_TYPE_SIZE) \
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: ~ (HOST_WIDEST_INT) 0)
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/* Suppose A1 + B1 = SUM1, using 2's complement arithmetic ignoring overflow.
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Suppose A, B and SUM have the same respective signs as A1, B1, and SUM1.
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Suppose SIGNEDP is negative if the result is signed, zero if unsigned.
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Then this yields nonzero if overflow occurred during the addition.
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Overflow occurs if A and B have the same sign, but A and SUM differ in sign,
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and SIGNEDP is negative.
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Use `^' to test whether signs differ, and `< 0' to isolate the sign. */
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#define overflow_sum_sign(a, b, sum, signedp) \
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((~((a) ^ (b)) & ((a) ^ (sum)) & (signedp)) < 0)
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struct constant;
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HOST_WIDEST_INT parse_escape PROTO((char **, HOST_WIDEST_INT));
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int check_assertion PROTO((U_CHAR *, int, int, struct arglist *));
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struct hashnode *lookup PROTO((U_CHAR *, int, int));
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void error PVPROTO((const char *, ...)) ATTRIBUTE_PRINTF_1;
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void verror PROTO((const char *, va_list));
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void pedwarn PVPROTO((const char *, ...)) ATTRIBUTE_PRINTF_1;
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void warning PVPROTO((const char *, ...)) ATTRIBUTE_PRINTF_1;
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static int parse_number PROTO((int));
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static HOST_WIDEST_INT left_shift PROTO((struct constant *, unsigned HOST_WIDEST_INT));
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static HOST_WIDEST_INT right_shift PROTO((struct constant *, unsigned HOST_WIDEST_INT));
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static void integer_overflow PROTO((void));
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/* `signedp' values */
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#define SIGNED (~0)
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#define UNSIGNED 0
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%}
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%union {
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struct constant {HOST_WIDEST_INT value; int signedp;} integer;
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struct name {U_CHAR *address; int length;} name;
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struct arglist *keywords;
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}
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%type <integer> exp exp1 start
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%type <keywords> keywords
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%token <integer> INT CHAR
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%token <name> NAME
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%token <integer> ERROR
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%right '?' ':'
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%left ','
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%left OR
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%left AND
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%left '|'
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%left '^'
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%left '&'
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%left EQUAL NOTEQUAL
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%left '<' '>' LEQ GEQ
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%left LSH RSH
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%left '+' '-'
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%left '*' '/' '%'
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%right UNARY
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/* %expect 40 */
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%%
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start : exp1
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{
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expression_value = $1.value;
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#ifdef TEST_EXP_READER
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expression_signedp = $1.signedp;
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#endif
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}
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;
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/* Expressions, including the comma operator. */
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exp1 : exp
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| exp1 ',' exp
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{ if (pedantic)
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pedwarn ("comma operator in operand of `#if'");
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$$ = $3; }
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;
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/* Expressions, not including the comma operator. */
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exp : '-' exp %prec UNARY
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{ $$.value = - $2.value;
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$$.signedp = $2.signedp;
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if (($$.value & $2.value & $$.signedp) < 0)
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integer_overflow (); }
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| '!' exp %prec UNARY
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{ $$.value = ! $2.value;
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$$.signedp = SIGNED; }
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| '+' exp %prec UNARY
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{ $$ = $2; }
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| '~' exp %prec UNARY
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{ $$.value = ~ $2.value;
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$$.signedp = $2.signedp; }
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| '#' NAME
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{ $$.value = check_assertion ($2.address, $2.length,
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0, NULL_PTR);
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$$.signedp = SIGNED; }
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| '#' NAME
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{ keyword_parsing = 1; }
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'(' keywords ')'
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{ $$.value = check_assertion ($2.address, $2.length,
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1, $5);
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keyword_parsing = 0;
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$$.signedp = SIGNED; }
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| '(' exp1 ')'
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{ $$ = $2; }
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;
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/* Binary operators in order of decreasing precedence. */
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exp : exp '*' exp
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{ $$.signedp = $1.signedp & $3.signedp;
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if ($$.signedp)
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{
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$$.value = $1.value * $3.value;
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if ($1.value
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&& ($$.value / $1.value != $3.value
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|| ($$.value & $1.value & $3.value) < 0))
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integer_overflow ();
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}
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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* $3.value); }
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| exp '/' exp
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{ if ($3.value == 0)
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{
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if (!skip_evaluation)
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error ("division by zero in #if");
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$3.value = 1;
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}
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$$.signedp = $1.signedp & $3.signedp;
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if ($$.signedp)
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{
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$$.value = $1.value / $3.value;
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if (($$.value & $1.value & $3.value) < 0)
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integer_overflow ();
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}
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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/ $3.value); }
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| exp '%' exp
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{ if ($3.value == 0)
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{
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if (!skip_evaluation)
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error ("division by zero in #if");
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$3.value = 1;
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}
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$$.signedp = $1.signedp & $3.signedp;
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if ($$.signedp)
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$$.value = $1.value % $3.value;
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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% $3.value); }
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| exp '+' exp
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{ $$.value = $1.value + $3.value;
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$$.signedp = $1.signedp & $3.signedp;
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if (overflow_sum_sign ($1.value, $3.value,
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$$.value, $$.signedp))
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integer_overflow (); }
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| exp '-' exp
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{ $$.value = $1.value - $3.value;
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$$.signedp = $1.signedp & $3.signedp;
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if (overflow_sum_sign ($$.value, $3.value,
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$1.value, $$.signedp))
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integer_overflow (); }
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| exp LSH exp
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{ $$.signedp = $1.signedp;
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if (($3.value & $3.signedp) < 0)
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$$.value = right_shift (&$1, -$3.value);
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else
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$$.value = left_shift (&$1, $3.value); }
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| exp RSH exp
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{ $$.signedp = $1.signedp;
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if (($3.value & $3.signedp) < 0)
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$$.value = left_shift (&$1, -$3.value);
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else
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$$.value = right_shift (&$1, $3.value); }
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| exp EQUAL exp
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{ $$.value = ($1.value == $3.value);
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$$.signedp = SIGNED; }
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| exp NOTEQUAL exp
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{ $$.value = ($1.value != $3.value);
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$$.signedp = SIGNED; }
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| exp LEQ exp
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{ $$.signedp = SIGNED;
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if ($1.signedp & $3.signedp)
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$$.value = $1.value <= $3.value;
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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<= $3.value); }
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| exp GEQ exp
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{ $$.signedp = SIGNED;
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if ($1.signedp & $3.signedp)
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$$.value = $1.value >= $3.value;
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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>= $3.value); }
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| exp '<' exp
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{ $$.signedp = SIGNED;
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if ($1.signedp & $3.signedp)
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$$.value = $1.value < $3.value;
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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< $3.value); }
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| exp '>' exp
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{ $$.signedp = SIGNED;
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if ($1.signedp & $3.signedp)
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$$.value = $1.value > $3.value;
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else
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$$.value = ((unsigned HOST_WIDEST_INT) $1.value
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> $3.value); }
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| exp '&' exp
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{ $$.value = $1.value & $3.value;
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$$.signedp = $1.signedp & $3.signedp; }
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| exp '^' exp
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{ $$.value = $1.value ^ $3.value;
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$$.signedp = $1.signedp & $3.signedp; }
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| exp '|' exp
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{ $$.value = $1.value | $3.value;
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$$.signedp = $1.signedp & $3.signedp; }
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| exp AND
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{ skip_evaluation += !$1.value; }
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exp
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{ skip_evaluation -= !$1.value;
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$$.value = ($1.value && $4.value);
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$$.signedp = SIGNED; }
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| exp OR
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{ skip_evaluation += !!$1.value; }
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exp
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{ skip_evaluation -= !!$1.value;
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$$.value = ($1.value || $4.value);
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$$.signedp = SIGNED; }
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| exp '?'
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{ skip_evaluation += !$1.value; }
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exp ':'
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{ skip_evaluation += !!$1.value - !$1.value; }
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exp
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{ skip_evaluation -= !!$1.value;
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$$.value = $1.value ? $4.value : $7.value;
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$$.signedp = $4.signedp & $7.signedp; }
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| INT
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{ $$ = yylval.integer; }
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| CHAR
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{ $$ = yylval.integer; }
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| NAME
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{ if (warn_undef && !skip_evaluation)
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warning ("`%.*s' is not defined",
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$1.length, $1.address);
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$$.value = 0;
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$$.signedp = SIGNED; }
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;
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keywords :
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{ $$ = 0; }
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| '(' keywords ')' keywords
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{ struct arglist *temp;
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$$ = (struct arglist *) xmalloc (sizeof (struct arglist));
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$$->next = $2;
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$$->name = (U_CHAR *) "(";
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$$->length = 1;
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temp = $$;
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while (temp != 0 && temp->next != 0)
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temp = temp->next;
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temp->next = (struct arglist *) xmalloc (sizeof (struct arglist));
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temp->next->next = $4;
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temp->next->name = (U_CHAR *) ")";
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temp->next->length = 1; }
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| NAME keywords
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{ $$ = (struct arglist *) xmalloc (sizeof (struct arglist));
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$$->name = $1.address;
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$$->length = $1.length;
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$$->next = $2; }
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;
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%%
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/* During parsing of a C expression, the pointer to the next character
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is in this variable. */
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static char *lexptr;
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/* Take care of parsing a number (anything that starts with a digit).
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Set yylval and return the token type; update lexptr.
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LEN is the number of characters in it. */
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/* maybe needs to actually deal with floating point numbers */
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static int
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parse_number (olen)
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int olen;
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{
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register char *p = lexptr;
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register int c;
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register unsigned HOST_WIDEST_INT n = 0, nd, max_over_base;
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register int base = 10;
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register int len = olen;
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register int overflow = 0;
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register int digit, largest_digit = 0;
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int spec_long = 0;
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yylval.integer.signedp = SIGNED;
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if (*p == '0') {
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base = 8;
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if (len >= 3 && (p[1] == 'x' || p[1] == 'X')) {
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p += 2;
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base = 16;
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len -= 2;
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}
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}
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max_over_base = (unsigned HOST_WIDEST_INT) -1 / base;
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for (; len > 0; len--) {
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c = *p++;
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if (c >= '0' && c <= '9')
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digit = c - '0';
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else if (base == 16 && c >= 'a' && c <= 'f')
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digit = c - 'a' + 10;
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else if (base == 16 && c >= 'A' && c <= 'F')
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digit = c - 'A' + 10;
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else {
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/* `l' means long, and `u' means unsigned. */
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while (1) {
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if (c == 'l' || c == 'L')
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{
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if (!pedantic < spec_long)
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yyerror ("too many `l's in integer constant");
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spec_long++;
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}
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else if (c == 'u' || c == 'U')
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{
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if (! yylval.integer.signedp)
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yyerror ("two `u's in integer constant");
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yylval.integer.signedp = UNSIGNED;
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}
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else {
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if (c == '.' || c == 'e' || c == 'E' || c == 'p' || c == 'P')
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yyerror ("Floating point numbers not allowed in #if expressions");
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else
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yyerror ("missing white space after number `%.*s'",
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(int) (p - lexptr - 1), lexptr);
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}
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if (--len == 0)
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break;
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c = *p++;
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}
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/* Don't look for any more digits after the suffixes. */
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break;
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}
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if (largest_digit < digit)
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largest_digit = digit;
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nd = n * base + digit;
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overflow |= (max_over_base < n) | (nd < n);
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n = nd;
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}
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if (base <= largest_digit)
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pedwarn ("integer constant contains digits beyond the radix");
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if (overflow)
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pedwarn ("integer constant out of range");
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/* If too big to be signed, consider it unsigned. */
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if (((HOST_WIDEST_INT) n & yylval.integer.signedp) < 0)
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{
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if (base == 10)
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warning ("integer constant is so large that it is unsigned");
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yylval.integer.signedp = UNSIGNED;
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}
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lexptr = p;
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yylval.integer.value = n;
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return INT;
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}
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|
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struct token {
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const char *operator;
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int token;
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};
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|
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static struct token tokentab2[] = {
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||
{"&&", AND},
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{"||", OR},
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{"<<", LSH},
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{">>", RSH},
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{"==", EQUAL},
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{"!=", NOTEQUAL},
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{"<=", LEQ},
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{">=", GEQ},
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{"++", ERROR},
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{"--", ERROR},
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{NULL, ERROR}
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};
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|
||
/* Read one token, getting characters through lexptr. */
|
||
|
||
static int
|
||
yylex ()
|
||
{
|
||
register int c;
|
||
register int namelen;
|
||
register unsigned char *tokstart;
|
||
register struct token *toktab;
|
||
int wide_flag;
|
||
HOST_WIDEST_INT mask;
|
||
|
||
retry:
|
||
|
||
tokstart = (unsigned char *) lexptr;
|
||
c = *tokstart;
|
||
/* See if it is a special token of length 2. */
|
||
if (! keyword_parsing)
|
||
for (toktab = tokentab2; toktab->operator != NULL; toktab++)
|
||
if (c == *toktab->operator && tokstart[1] == toktab->operator[1]) {
|
||
lexptr += 2;
|
||
if (toktab->token == ERROR)
|
||
yyerror ("`%s' not allowed in operand of `#if'", toktab->operator);
|
||
return toktab->token;
|
||
}
|
||
|
||
switch (c) {
|
||
case '\n':
|
||
return 0;
|
||
|
||
case ' ':
|
||
case '\t':
|
||
case '\r':
|
||
lexptr++;
|
||
goto retry;
|
||
|
||
case 'L':
|
||
/* Capital L may start a wide-string or wide-character constant. */
|
||
if (lexptr[1] == '\'')
|
||
{
|
||
lexptr++;
|
||
wide_flag = 1;
|
||
mask = MAX_WCHAR_TYPE_MASK;
|
||
goto char_constant;
|
||
}
|
||
if (lexptr[1] == '"')
|
||
{
|
||
lexptr++;
|
||
wide_flag = 1;
|
||
mask = MAX_WCHAR_TYPE_MASK;
|
||
goto string_constant;
|
||
}
|
||
break;
|
||
|
||
case '\'':
|
||
wide_flag = 0;
|
||
mask = MAX_CHAR_TYPE_MASK;
|
||
char_constant:
|
||
lexptr++;
|
||
if (keyword_parsing) {
|
||
char *start_ptr = lexptr - 1;
|
||
while (1) {
|
||
c = *lexptr++;
|
||
if (c == '\\')
|
||
c = parse_escape (&lexptr, mask);
|
||
else if (c == '\'')
|
||
break;
|
||
}
|
||
yylval.name.address = tokstart;
|
||
yylval.name.length = lexptr - start_ptr;
|
||
return NAME;
|
||
}
|
||
|
||
/* This code for reading a character constant
|
||
handles multicharacter constants and wide characters.
|
||
It is mostly copied from c-lex.c. */
|
||
{
|
||
register HOST_WIDEST_INT result = 0;
|
||
register int num_chars = 0;
|
||
int chars_seen = 0;
|
||
unsigned width = MAX_CHAR_TYPE_SIZE;
|
||
int max_chars;
|
||
#ifdef MULTIBYTE_CHARS
|
||
int longest_char = local_mb_cur_max ();
|
||
char *token_buffer = (char *) alloca (longest_char);
|
||
(void) local_mbtowc (NULL_PTR, NULL_PTR, 0);
|
||
#endif
|
||
|
||
max_chars = MAX_LONG_TYPE_SIZE / width;
|
||
if (wide_flag)
|
||
width = MAX_WCHAR_TYPE_SIZE;
|
||
|
||
while (1)
|
||
{
|
||
c = *lexptr++;
|
||
|
||
if (c == '\'' || c == EOF)
|
||
break;
|
||
|
||
++chars_seen;
|
||
if (c == '\\')
|
||
{
|
||
c = parse_escape (&lexptr, mask);
|
||
}
|
||
else
|
||
{
|
||
#ifdef MULTIBYTE_CHARS
|
||
wchar_t wc;
|
||
int i;
|
||
int char_len = -1;
|
||
for (i = 1; i <= longest_char; ++i)
|
||
{
|
||
token_buffer[i - 1] = c;
|
||
char_len = local_mbtowc (& wc, token_buffer, i);
|
||
if (char_len != -1)
|
||
break;
|
||
c = *lexptr++;
|
||
}
|
||
if (char_len > 1)
|
||
{
|
||
/* mbtowc sometimes needs an extra char before accepting */
|
||
if (char_len < i)
|
||
lexptr--;
|
||
if (! wide_flag)
|
||
{
|
||
/* Merge character into result; ignore excess chars. */
|
||
for (i = 1; i <= char_len; ++i)
|
||
{
|
||
if (i > max_chars)
|
||
break;
|
||
if (width < HOST_BITS_PER_INT)
|
||
result = (result << width)
|
||
| (token_buffer[i - 1]
|
||
& ((1 << width) - 1));
|
||
else
|
||
result = token_buffer[i - 1];
|
||
}
|
||
num_chars += char_len;
|
||
continue;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
if (char_len == -1)
|
||
warning ("Ignoring invalid multibyte character");
|
||
}
|
||
if (wide_flag)
|
||
c = wc;
|
||
#endif /* ! MULTIBYTE_CHARS */
|
||
}
|
||
|
||
if (wide_flag)
|
||
{
|
||
if (chars_seen == 1) /* only keep the first one */
|
||
result = c;
|
||
continue;
|
||
}
|
||
|
||
/* Merge character into result; ignore excess chars. */
|
||
num_chars++;
|
||
if (num_chars <= max_chars)
|
||
{
|
||
if (width < HOST_BITS_PER_INT)
|
||
result = (result << width) | (c & ((1 << width) - 1));
|
||
else
|
||
result = c;
|
||
}
|
||
}
|
||
|
||
if (c != '\'')
|
||
error ("malformatted character constant");
|
||
else if (chars_seen == 0)
|
||
error ("empty character constant");
|
||
else if (num_chars > max_chars)
|
||
{
|
||
num_chars = max_chars;
|
||
error ("character constant too long");
|
||
}
|
||
else if (chars_seen != 1 && ! traditional)
|
||
warning ("multi-character character constant");
|
||
|
||
/* If char type is signed, sign-extend the constant. */
|
||
if (! wide_flag)
|
||
{
|
||
int num_bits = num_chars * width;
|
||
if (num_bits == 0)
|
||
/* We already got an error; avoid invalid shift. */
|
||
yylval.integer.value = 0;
|
||
else if (lookup ((U_CHAR *) "__CHAR_UNSIGNED__",
|
||
sizeof ("__CHAR_UNSIGNED__") - 1, -1)
|
||
|| ((result >> (num_bits - 1)) & 1) == 0)
|
||
yylval.integer.value
|
||
= result & (~ (unsigned HOST_WIDEST_INT) 0
|
||
>> (HOST_BITS_PER_WIDEST_INT - num_bits));
|
||
else
|
||
yylval.integer.value
|
||
= result | ~(~ (unsigned HOST_WIDEST_INT) 0
|
||
>> (HOST_BITS_PER_WIDEST_INT - num_bits));
|
||
}
|
||
else
|
||
{
|
||
yylval.integer.value = result;
|
||
}
|
||
}
|
||
|
||
/* This is always a signed type. */
|
||
yylval.integer.signedp = SIGNED;
|
||
|
||
return CHAR;
|
||
|
||
/* some of these chars are invalid in constant expressions;
|
||
maybe do something about them later */
|
||
case '/':
|
||
case '+':
|
||
case '-':
|
||
case '*':
|
||
case '%':
|
||
case '|':
|
||
case '&':
|
||
case '^':
|
||
case '~':
|
||
case '!':
|
||
case '@':
|
||
case '<':
|
||
case '>':
|
||
case '[':
|
||
case ']':
|
||
case '.':
|
||
case '?':
|
||
case ':':
|
||
case '=':
|
||
case '{':
|
||
case '}':
|
||
case ',':
|
||
case '#':
|
||
if (keyword_parsing)
|
||
break;
|
||
case '(':
|
||
case ')':
|
||
lexptr++;
|
||
return c;
|
||
|
||
case '"':
|
||
mask = MAX_CHAR_TYPE_MASK;
|
||
string_constant:
|
||
if (keyword_parsing) {
|
||
char *start_ptr = lexptr;
|
||
lexptr++;
|
||
while (1) {
|
||
c = *lexptr++;
|
||
if (c == '\\')
|
||
c = parse_escape (&lexptr, mask);
|
||
else if (c == '"')
|
||
break;
|
||
}
|
||
yylval.name.address = tokstart;
|
||
yylval.name.length = lexptr - start_ptr;
|
||
return NAME;
|
||
}
|
||
yyerror ("string constants not allowed in #if expressions");
|
||
return ERROR;
|
||
}
|
||
|
||
if (c >= '0' && c <= '9' && !keyword_parsing) {
|
||
/* It's a number */
|
||
for (namelen = 1; ; namelen++) {
|
||
int d = tokstart[namelen];
|
||
if (! ((is_idchar[d] || d == '.')
|
||
|| ((d == '-' || d == '+')
|
||
&& (c == 'e' || c == 'E'
|
||
|| ((c == 'p' || c == 'P') && ! c89))
|
||
&& ! traditional)))
|
||
break;
|
||
c = d;
|
||
}
|
||
return parse_number (namelen);
|
||
}
|
||
|
||
/* It is a name. See how long it is. */
|
||
|
||
if (keyword_parsing) {
|
||
for (namelen = 0;; namelen++) {
|
||
if (is_space[tokstart[namelen]])
|
||
break;
|
||
if (tokstart[namelen] == '(' || tokstart[namelen] == ')')
|
||
break;
|
||
if (tokstart[namelen] == '"' || tokstart[namelen] == '\'')
|
||
break;
|
||
}
|
||
} else {
|
||
if (!is_idstart[c]) {
|
||
yyerror ("Invalid token in expression");
|
||
return ERROR;
|
||
}
|
||
|
||
for (namelen = 0; is_idchar[tokstart[namelen]]; namelen++)
|
||
;
|
||
}
|
||
|
||
lexptr += namelen;
|
||
yylval.name.address = tokstart;
|
||
yylval.name.length = namelen;
|
||
return NAME;
|
||
}
|
||
|
||
|
||
/* Parse a C escape sequence. STRING_PTR points to a variable
|
||
containing a pointer to the string to parse. That pointer
|
||
is updated past the characters we use. The value of the
|
||
escape sequence is returned.
|
||
|
||
RESULT_MASK is used to mask out the result;
|
||
an error is reported if bits are lost thereby.
|
||
|
||
A negative value means the sequence \ newline was seen,
|
||
which is supposed to be equivalent to nothing at all.
|
||
|
||
If \ is followed by a null character, we return a negative
|
||
value and leave the string pointer pointing at the null character.
|
||
|
||
If \ is followed by 000, we return 0 and leave the string pointer
|
||
after the zeros. A value of 0 does not mean end of string. */
|
||
|
||
HOST_WIDEST_INT
|
||
parse_escape (string_ptr, result_mask)
|
||
char **string_ptr;
|
||
HOST_WIDEST_INT result_mask;
|
||
{
|
||
register int c = *(*string_ptr)++;
|
||
switch (c)
|
||
{
|
||
case 'a':
|
||
return TARGET_BELL;
|
||
case 'b':
|
||
return TARGET_BS;
|
||
case 'e':
|
||
case 'E':
|
||
if (pedantic)
|
||
pedwarn ("non-ANSI-standard escape sequence, `\\%c'", c);
|
||
return 033;
|
||
case 'f':
|
||
return TARGET_FF;
|
||
case 'n':
|
||
return TARGET_NEWLINE;
|
||
case 'r':
|
||
return TARGET_CR;
|
||
case 't':
|
||
return TARGET_TAB;
|
||
case 'v':
|
||
return TARGET_VT;
|
||
case '\n':
|
||
return -2;
|
||
case 0:
|
||
(*string_ptr)--;
|
||
return 0;
|
||
|
||
case '0':
|
||
case '1':
|
||
case '2':
|
||
case '3':
|
||
case '4':
|
||
case '5':
|
||
case '6':
|
||
case '7':
|
||
{
|
||
register HOST_WIDEST_INT i = c - '0';
|
||
register int count = 0;
|
||
while (++count < 3)
|
||
{
|
||
c = *(*string_ptr)++;
|
||
if (c >= '0' && c <= '7')
|
||
i = (i << 3) + c - '0';
|
||
else
|
||
{
|
||
(*string_ptr)--;
|
||
break;
|
||
}
|
||
}
|
||
if (i != (i & result_mask))
|
||
{
|
||
i &= result_mask;
|
||
pedwarn ("octal escape sequence out of range");
|
||
}
|
||
return i;
|
||
}
|
||
case 'x':
|
||
{
|
||
register unsigned HOST_WIDEST_INT i = 0, overflow = 0;
|
||
register int digits_found = 0, digit;
|
||
for (;;)
|
||
{
|
||
c = *(*string_ptr)++;
|
||
if (c >= '0' && c <= '9')
|
||
digit = c - '0';
|
||
else if (c >= 'a' && c <= 'f')
|
||
digit = c - 'a' + 10;
|
||
else if (c >= 'A' && c <= 'F')
|
||
digit = c - 'A' + 10;
|
||
else
|
||
{
|
||
(*string_ptr)--;
|
||
break;
|
||
}
|
||
overflow |= i ^ (i << 4 >> 4);
|
||
i = (i << 4) + digit;
|
||
digits_found = 1;
|
||
}
|
||
if (!digits_found)
|
||
yyerror ("\\x used with no following hex digits");
|
||
if (overflow | (i != (i & result_mask)))
|
||
{
|
||
i &= result_mask;
|
||
pedwarn ("hex escape sequence out of range");
|
||
}
|
||
return i;
|
||
}
|
||
default:
|
||
return c;
|
||
}
|
||
}
|
||
|
||
static void
|
||
integer_overflow ()
|
||
{
|
||
if (!skip_evaluation && pedantic)
|
||
pedwarn ("integer overflow in preprocessor expression");
|
||
}
|
||
|
||
static HOST_WIDEST_INT
|
||
left_shift (a, b)
|
||
struct constant *a;
|
||
unsigned HOST_WIDEST_INT b;
|
||
{
|
||
/* It's unclear from the C standard whether shifts can overflow.
|
||
The following code ignores overflow; perhaps a C standard
|
||
interpretation ruling is needed. */
|
||
if (b >= HOST_BITS_PER_WIDEST_INT)
|
||
return 0;
|
||
else
|
||
return (unsigned HOST_WIDEST_INT) a->value << b;
|
||
}
|
||
|
||
static HOST_WIDEST_INT
|
||
right_shift (a, b)
|
||
struct constant *a;
|
||
unsigned HOST_WIDEST_INT b;
|
||
{
|
||
if (b >= HOST_BITS_PER_WIDEST_INT)
|
||
return a->signedp ? a->value >> (HOST_BITS_PER_WIDEST_INT - 1) : 0;
|
||
else if (a->signedp)
|
||
return a->value >> b;
|
||
else
|
||
return (unsigned HOST_WIDEST_INT) a->value >> b;
|
||
}
|
||
|
||
/* This page contains the entry point to this file. */
|
||
|
||
/* Parse STRING as an expression, and complain if this fails
|
||
to use up all of the contents of STRING.
|
||
STRING may contain '\0' bytes; it is terminated by the first '\n'
|
||
outside a string constant, so that we can diagnose '\0' properly.
|
||
If WARN_UNDEFINED is nonzero, warn if undefined identifiers are evaluated.
|
||
We do not support C comments. They should be removed before
|
||
this function is called. */
|
||
|
||
HOST_WIDEST_INT
|
||
parse_c_expression (string, warn_undefined)
|
||
char *string;
|
||
int warn_undefined;
|
||
{
|
||
lexptr = string;
|
||
warn_undef = warn_undefined;
|
||
|
||
/* if there is some sort of scanning error, just return 0 and assume
|
||
the parsing routine has printed an error message somewhere.
|
||
there is surely a better thing to do than this. */
|
||
if (setjmp (parse_return_error))
|
||
return 0;
|
||
|
||
if (yyparse () != 0)
|
||
abort ();
|
||
|
||
if (*lexptr != '\n')
|
||
error ("Junk after end of expression.");
|
||
|
||
return expression_value; /* set by yyparse () */
|
||
}
|
||
|
||
static void
|
||
yyerror VPROTO ((const char * msgid, ...))
|
||
{
|
||
#ifndef ANSI_PROTOTYPES
|
||
const char * msgid;
|
||
#endif
|
||
va_list args;
|
||
|
||
VA_START (args, msgid);
|
||
|
||
#ifndef ANSI_PROTOTYPES
|
||
msgid = va_arg (args, const char *);
|
||
#endif
|
||
|
||
verror (msgid, args);
|
||
va_end (args);
|
||
skip_evaluation = 0;
|
||
longjmp (parse_return_error, 1);
|
||
}
|
||
|
||
|
||
#ifdef TEST_EXP_READER
|
||
|
||
#if YYDEBUG
|
||
extern int yydebug;
|
||
#endif
|
||
|
||
int pedantic;
|
||
int traditional;
|
||
int c89;
|
||
|
||
int main PROTO((int, char **));
|
||
static void initialize_random_junk PROTO((void));
|
||
static void print_unsigned_host_widest_int PROTO((unsigned HOST_WIDEST_INT));
|
||
|
||
/* Main program for testing purposes. */
|
||
int
|
||
main (argc, argv)
|
||
int argc;
|
||
char **argv;
|
||
{
|
||
int n, c;
|
||
char buf[1024];
|
||
unsigned HOST_WIDEST_INT u;
|
||
|
||
pedantic = 1 < argc;
|
||
traditional = 2 < argc;
|
||
c89 = 3 < argc;
|
||
#if YYDEBUG
|
||
yydebug = 4 < argc;
|
||
#endif
|
||
initialize_random_junk ();
|
||
|
||
for (;;) {
|
||
printf ("enter expression: ");
|
||
n = 0;
|
||
while ((buf[n] = c = getchar ()) != '\n' && c != EOF)
|
||
n++;
|
||
if (c == EOF)
|
||
break;
|
||
parse_c_expression (buf, 1);
|
||
printf ("parser returned ");
|
||
u = (unsigned HOST_WIDEST_INT) expression_value;
|
||
if (expression_value < 0 && expression_signedp) {
|
||
u = -u;
|
||
printf ("-");
|
||
}
|
||
if (u == 0)
|
||
printf ("0");
|
||
else
|
||
print_unsigned_host_widest_int (u);
|
||
if (! expression_signedp)
|
||
printf("u");
|
||
printf ("\n");
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
static void
|
||
print_unsigned_host_widest_int (u)
|
||
unsigned HOST_WIDEST_INT u;
|
||
{
|
||
if (u) {
|
||
print_unsigned_host_widest_int (u / 10);
|
||
putchar ('0' + (int) (u % 10));
|
||
}
|
||
}
|
||
|
||
/* table to tell if char can be part of a C identifier. */
|
||
unsigned char is_idchar[256];
|
||
/* table to tell if char can be first char of a c identifier. */
|
||
unsigned char is_idstart[256];
|
||
/* table to tell if c is horizontal or vertical space. */
|
||
unsigned char is_space[256];
|
||
|
||
/*
|
||
* initialize random junk in the hash table and maybe other places
|
||
*/
|
||
static void
|
||
initialize_random_junk ()
|
||
{
|
||
register int i;
|
||
|
||
/*
|
||
* Set up is_idchar and is_idstart tables. These should be
|
||
* faster than saying (is_alpha (c) || c == '_'), etc.
|
||
* Must do set up these things before calling any routines tthat
|
||
* refer to them.
|
||
*/
|
||
for (i = 'a'; i <= 'z'; i++) {
|
||
++is_idchar[i - 'a' + 'A'];
|
||
++is_idchar[i];
|
||
++is_idstart[i - 'a' + 'A'];
|
||
++is_idstart[i];
|
||
}
|
||
for (i = '0'; i <= '9'; i++)
|
||
++is_idchar[i];
|
||
++is_idchar['_'];
|
||
++is_idstart['_'];
|
||
++is_idchar['$'];
|
||
++is_idstart['$'];
|
||
|
||
++is_space[' '];
|
||
++is_space['\t'];
|
||
++is_space['\v'];
|
||
++is_space['\f'];
|
||
++is_space['\n'];
|
||
++is_space['\r'];
|
||
}
|
||
|
||
void
|
||
error VPROTO ((char * msgid, ...))
|
||
{
|
||
#ifndef ANSI_PROTOTYPES
|
||
char * msgid;
|
||
#endif
|
||
va_list args;
|
||
|
||
VA_START (args, msgid);
|
||
|
||
#ifndef ANSI_PROTOTYPES
|
||
msgid = va_arg (args, char *);
|
||
#endif
|
||
|
||
fprintf (stderr, "error: ");
|
||
vfprintf (stderr, _(msgid), args);
|
||
fprintf (stderr, "\n");
|
||
va_end (args);
|
||
}
|
||
|
||
void
|
||
pedwarn VPROTO ((char * msgid, ...))
|
||
{
|
||
#ifndef ANSI_PROTOTYPES
|
||
char * msgid;
|
||
#endif
|
||
va_list args;
|
||
|
||
VA_START (args, msgid);
|
||
|
||
#ifndef ANSI_PROTOTYPES
|
||
msgid = va_arg (args, char *);
|
||
#endif
|
||
|
||
fprintf (stderr, "pedwarn: ");
|
||
vfprintf (stderr, _(msgid), args);
|
||
fprintf (stderr, "\n");
|
||
va_end (args);
|
||
}
|
||
|
||
void
|
||
warning VPROTO ((char * msgid, ...))
|
||
{
|
||
#ifndef ANSI_PROTOTYPES
|
||
char * msgid;
|
||
#endif
|
||
va_list args;
|
||
|
||
VA_START (args, msgid);
|
||
|
||
#ifndef ANSI_PROTOTYPES
|
||
msgid = va_arg (args, char *);
|
||
#endif
|
||
|
||
fprintf (stderr, "warning: ");
|
||
vfprintf (stderr, _(msgid), args);
|
||
fprintf (stderr, "\n");
|
||
va_end (args);
|
||
}
|
||
|
||
|
||
int
|
||
check_assertion (name, sym_length, tokens_specified, tokens)
|
||
U_CHAR *name;
|
||
int sym_length;
|
||
int tokens_specified;
|
||
struct arglist *tokens;
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
struct hashnode *
|
||
lookup (name, len, hash)
|
||
U_CHAR *name;
|
||
int len;
|
||
int hash;
|
||
{
|
||
return (DEFAULT_SIGNED_CHAR) ? 0 : ((struct hashnode *) -1);
|
||
}
|
||
|
||
PTR
|
||
xmalloc (size)
|
||
size_t size;
|
||
{
|
||
return (PTR) malloc (size);
|
||
}
|
||
#endif
|