[8833] | 1 | /* Parse C expressions for CCCP. |
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| 2 | Copyright (C) 1987, 1992, 1994, 1995 Free Software Foundation. |
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| 3 | |
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| 4 | This program is free software; you can redistribute it and/or modify it |
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| 5 | under the terms of the GNU General Public License as published by the |
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| 6 | Free Software Foundation; either version 2, or (at your option) any |
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| 7 | later version. |
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| 8 | |
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| 9 | This program is distributed in the hope that it will be useful, |
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| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 12 | GNU General Public License for more details. |
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| 13 | |
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| 14 | You should have received a copy of the GNU General Public License |
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| 15 | along with this program; if not, write to the Free Software |
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| 16 | Foundation, 59 Temple Place - Suite 330, |
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| 17 | Boston, MA 02111-1307, USA. |
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| 18 | |
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| 19 | In other words, you are welcome to use, share and improve this program. |
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| 20 | You are forbidden to forbid anyone else to use, share and improve |
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| 21 | what you give them. Help stamp out software-hoarding! |
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| 22 | |
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| 23 | Adapted from expread.y of GDB by Paul Rubin, July 1986. */ |
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| 24 | |
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| 25 | /* Parse a C expression from text in a string */ |
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| 26 | |
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| 27 | %{ |
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| 28 | #include "config.h" |
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| 29 | #include <setjmp.h> |
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| 30 | /* #define YYDEBUG 1 */ |
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| 31 | |
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| 32 | #ifdef MULTIBYTE_CHARS |
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| 33 | #include <stdlib.h> |
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| 34 | #include <locale.h> |
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| 35 | #endif |
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| 36 | |
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| 37 | #include <stdio.h> |
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| 38 | |
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| 39 | typedef unsigned char U_CHAR; |
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| 40 | |
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| 41 | /* This is used for communicating lists of keywords with cccp.c. */ |
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| 42 | struct arglist { |
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| 43 | struct arglist *next; |
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| 44 | U_CHAR *name; |
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| 45 | int length; |
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| 46 | int argno; |
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| 47 | }; |
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| 48 | |
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| 49 | /* Define a generic NULL if one hasn't already been defined. */ |
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| 50 | |
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| 51 | #ifndef NULL |
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| 52 | #define NULL 0 |
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| 53 | #endif |
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| 54 | |
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| 55 | #ifndef GENERIC_PTR |
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| 56 | #if defined (USE_PROTOTYPES) ? USE_PROTOTYPES : defined (__STDC__) |
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| 57 | #define GENERIC_PTR void * |
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| 58 | #else |
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| 59 | #define GENERIC_PTR char * |
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| 60 | #endif |
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| 61 | #endif |
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| 62 | |
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| 63 | /* Find the largest host integer type and set its size and type. */ |
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| 64 | |
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| 65 | #ifndef HOST_BITS_PER_WIDE_INT |
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| 66 | |
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| 67 | #if HOST_BITS_PER_LONG > HOST_BITS_PER_INT |
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| 68 | #define HOST_BITS_PER_WIDE_INT HOST_BITS_PER_LONG |
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| 69 | #define HOST_WIDE_INT long |
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| 70 | #else |
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| 71 | #define HOST_BITS_PER_WIDE_INT HOST_BITS_PER_INT |
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| 72 | #define HOST_WIDE_INT int |
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| 73 | #endif |
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| 74 | |
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| 75 | #endif |
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| 76 | |
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| 77 | #ifndef NULL_PTR |
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| 78 | #define NULL_PTR ((GENERIC_PTR)0) |
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| 79 | #endif |
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| 80 | |
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| 81 | int yylex (); |
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| 82 | void yyerror (); |
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| 83 | HOST_WIDE_INT expression_value; |
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| 84 | |
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| 85 | static jmp_buf parse_return_error; |
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| 86 | |
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| 87 | /* Nonzero means count most punctuation as part of a name. */ |
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| 88 | static int keyword_parsing = 0; |
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| 89 | |
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| 90 | /* Nonzero means do not evaluate this expression. |
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| 91 | This is a count, since unevaluated expressions can nest. */ |
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| 92 | static int skip_evaluation; |
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| 93 | |
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| 94 | /* some external tables of character types */ |
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| 95 | extern unsigned char is_idstart[], is_idchar[], is_hor_space[]; |
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| 96 | |
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| 97 | extern char *xmalloc (); |
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| 98 | |
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| 99 | /* Flag for -pedantic. */ |
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| 100 | extern int pedantic; |
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| 101 | |
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| 102 | /* Flag for -traditional. */ |
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| 103 | extern int traditional; |
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| 104 | |
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| 105 | #ifndef CHAR_TYPE_SIZE |
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| 106 | #define CHAR_TYPE_SIZE BITS_PER_UNIT |
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| 107 | #endif |
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| 108 | |
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| 109 | #ifndef INT_TYPE_SIZE |
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| 110 | #define INT_TYPE_SIZE BITS_PER_WORD |
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| 111 | #endif |
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| 112 | |
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| 113 | #ifndef LONG_TYPE_SIZE |
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| 114 | #define LONG_TYPE_SIZE BITS_PER_WORD |
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| 115 | #endif |
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| 116 | |
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| 117 | #ifndef WCHAR_TYPE_SIZE |
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| 118 | #define WCHAR_TYPE_SIZE INT_TYPE_SIZE |
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| 119 | #endif |
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| 120 | |
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| 121 | #ifndef MAX_CHAR_TYPE_SIZE |
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| 122 | #define MAX_CHAR_TYPE_SIZE CHAR_TYPE_SIZE |
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| 123 | #endif |
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| 124 | |
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| 125 | #ifndef MAX_INT_TYPE_SIZE |
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| 126 | #define MAX_INT_TYPE_SIZE INT_TYPE_SIZE |
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| 127 | #endif |
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| 128 | |
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| 129 | #ifndef MAX_LONG_TYPE_SIZE |
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| 130 | #define MAX_LONG_TYPE_SIZE LONG_TYPE_SIZE |
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| 131 | #endif |
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| 132 | |
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| 133 | #ifndef MAX_WCHAR_TYPE_SIZE |
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| 134 | #define MAX_WCHAR_TYPE_SIZE WCHAR_TYPE_SIZE |
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| 135 | #endif |
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| 136 | |
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| 137 | /* Yield nonzero if adding two numbers with A's and B's signs can yield a |
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| 138 | number with SUM's sign, where A, B, and SUM are all C integers. */ |
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| 139 | #define possible_sum_sign(a, b, sum) ((((a) ^ (b)) | ~ ((a) ^ (sum))) < 0) |
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| 140 | |
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| 141 | static void integer_overflow (); |
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| 142 | static long left_shift (); |
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| 143 | static long right_shift (); |
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| 144 | %} |
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| 145 | |
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| 146 | %union { |
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| 147 | struct constant {long value; int unsignedp;} integer; |
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| 148 | struct name {U_CHAR *address; int length;} name; |
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| 149 | struct arglist *keywords; |
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| 150 | } |
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| 151 | |
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| 152 | %type <integer> exp exp1 start |
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| 153 | %type <keywords> keywords |
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| 154 | %token <integer> INT CHAR |
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| 155 | %token <name> NAME |
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| 156 | %token <integer> ERROR |
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| 157 | |
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| 158 | %right '?' ':' |
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| 159 | %left ',' |
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| 160 | %left OR |
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| 161 | %left AND |
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| 162 | %left '|' |
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| 163 | %left '^' |
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| 164 | %left '&' |
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| 165 | %left EQUAL NOTEQUAL |
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| 166 | %left '<' '>' LEQ GEQ |
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| 167 | %left LSH RSH |
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| 168 | %left '+' '-' |
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| 169 | %left '*' '/' '%' |
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| 170 | %right UNARY |
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| 171 | |
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| 172 | /* %expect 40 */ |
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| 173 | |
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| 174 | %% |
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| 175 | |
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| 176 | start : exp1 |
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| 177 | { expression_value = $1.value; } |
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| 178 | ; |
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| 179 | |
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| 180 | /* Expressions, including the comma operator. */ |
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| 181 | exp1 : exp |
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| 182 | | exp1 ',' exp |
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| 183 | { if (pedantic) |
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| 184 | pedwarn ("comma operator in operand of `#if'"); |
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| 185 | $$ = $3; } |
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| 186 | ; |
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| 187 | |
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| 188 | /* Expressions, not including the comma operator. */ |
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| 189 | exp : '-' exp %prec UNARY |
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| 190 | { $$.value = - $2.value; |
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| 191 | if (($$.value & $2.value) < 0 && ! $2.unsignedp) |
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| 192 | integer_overflow (); |
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| 193 | $$.unsignedp = $2.unsignedp; } |
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| 194 | | '!' exp %prec UNARY |
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| 195 | { $$.value = ! $2.value; |
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| 196 | $$.unsignedp = 0; } |
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| 197 | | '+' exp %prec UNARY |
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| 198 | { $$ = $2; } |
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| 199 | | '~' exp %prec UNARY |
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| 200 | { $$.value = ~ $2.value; |
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| 201 | $$.unsignedp = $2.unsignedp; } |
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| 202 | | '#' NAME |
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| 203 | { $$.value = check_assertion ($2.address, $2.length, |
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| 204 | 0, NULL_PTR); |
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| 205 | $$.unsignedp = 0; } |
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| 206 | | '#' NAME |
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| 207 | { keyword_parsing = 1; } |
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| 208 | '(' keywords ')' |
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| 209 | { $$.value = check_assertion ($2.address, $2.length, |
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| 210 | 1, $5); |
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| 211 | keyword_parsing = 0; |
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| 212 | $$.unsignedp = 0; } |
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| 213 | | '(' exp1 ')' |
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| 214 | { $$ = $2; } |
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| 215 | ; |
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| 216 | |
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| 217 | /* Binary operators in order of decreasing precedence. */ |
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| 218 | exp : exp '*' exp |
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| 219 | { $$.unsignedp = $1.unsignedp || $3.unsignedp; |
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| 220 | if ($$.unsignedp) |
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| 221 | $$.value = (unsigned long) $1.value * $3.value; |
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| 222 | else |
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| 223 | { |
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| 224 | $$.value = $1.value * $3.value; |
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| 225 | if ($1.value |
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| 226 | && ($$.value / $1.value != $3.value |
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| 227 | || ($$.value & $1.value & $3.value) < 0)) |
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| 228 | integer_overflow (); |
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| 229 | } } |
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| 230 | | exp '/' exp |
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| 231 | { if ($3.value == 0) |
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| 232 | { |
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| 233 | if (!skip_evaluation) |
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| 234 | error ("division by zero in #if"); |
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| 235 | $3.value = 1; |
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| 236 | } |
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| 237 | $$.unsignedp = $1.unsignedp || $3.unsignedp; |
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| 238 | if ($$.unsignedp) |
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| 239 | $$.value = (unsigned long) $1.value / $3.value; |
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| 240 | else |
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| 241 | { |
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| 242 | $$.value = $1.value / $3.value; |
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| 243 | if (($$.value & $1.value & $3.value) < 0) |
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| 244 | integer_overflow (); |
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| 245 | } } |
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| 246 | | exp '%' exp |
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| 247 | { if ($3.value == 0) |
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| 248 | { |
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| 249 | if (!skip_evaluation) |
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| 250 | error ("division by zero in #if"); |
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| 251 | $3.value = 1; |
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| 252 | } |
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| 253 | $$.unsignedp = $1.unsignedp || $3.unsignedp; |
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| 254 | if ($$.unsignedp) |
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| 255 | $$.value = (unsigned long) $1.value % $3.value; |
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| 256 | else |
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| 257 | $$.value = $1.value % $3.value; } |
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| 258 | | exp '+' exp |
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| 259 | { $$.value = $1.value + $3.value; |
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| 260 | $$.unsignedp = $1.unsignedp || $3.unsignedp; |
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| 261 | if (! $$.unsignedp |
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| 262 | && ! possible_sum_sign ($1.value, $3.value, |
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| 263 | $$.value)) |
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| 264 | integer_overflow (); } |
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| 265 | | exp '-' exp |
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| 266 | { $$.value = $1.value - $3.value; |
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| 267 | $$.unsignedp = $1.unsignedp || $3.unsignedp; |
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| 268 | if (! $$.unsignedp |
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| 269 | && ! possible_sum_sign ($$.value, $3.value, |
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| 270 | $1.value)) |
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| 271 | integer_overflow (); } |
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| 272 | | exp LSH exp |
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| 273 | { $$.unsignedp = $1.unsignedp; |
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| 274 | if ($3.value < 0 && ! $3.unsignedp) |
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| 275 | $$.value = right_shift (&$1, -$3.value); |
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| 276 | else |
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| 277 | $$.value = left_shift (&$1, $3.value); } |
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| 278 | | exp RSH exp |
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| 279 | { $$.unsignedp = $1.unsignedp; |
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| 280 | if ($3.value < 0 && ! $3.unsignedp) |
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| 281 | $$.value = left_shift (&$1, -$3.value); |
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| 282 | else |
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| 283 | $$.value = right_shift (&$1, $3.value); } |
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| 284 | | exp EQUAL exp |
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| 285 | { $$.value = ($1.value == $3.value); |
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| 286 | $$.unsignedp = 0; } |
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| 287 | | exp NOTEQUAL exp |
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| 288 | { $$.value = ($1.value != $3.value); |
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| 289 | $$.unsignedp = 0; } |
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| 290 | | exp LEQ exp |
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| 291 | { $$.unsignedp = 0; |
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| 292 | if ($1.unsignedp || $3.unsignedp) |
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| 293 | $$.value = (unsigned long) $1.value <= $3.value; |
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| 294 | else |
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| 295 | $$.value = $1.value <= $3.value; } |
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| 296 | | exp GEQ exp |
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| 297 | { $$.unsignedp = 0; |
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| 298 | if ($1.unsignedp || $3.unsignedp) |
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| 299 | $$.value = (unsigned long) $1.value >= $3.value; |
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| 300 | else |
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| 301 | $$.value = $1.value >= $3.value; } |
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| 302 | | exp '<' exp |
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| 303 | { $$.unsignedp = 0; |
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| 304 | if ($1.unsignedp || $3.unsignedp) |
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| 305 | $$.value = (unsigned long) $1.value < $3.value; |
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| 306 | else |
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| 307 | $$.value = $1.value < $3.value; } |
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| 308 | | exp '>' exp |
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| 309 | { $$.unsignedp = 0; |
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| 310 | if ($1.unsignedp || $3.unsignedp) |
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| 311 | $$.value = (unsigned long) $1.value > $3.value; |
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| 312 | else |
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| 313 | $$.value = $1.value > $3.value; } |
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| 314 | | exp '&' exp |
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| 315 | { $$.value = $1.value & $3.value; |
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| 316 | $$.unsignedp = $1.unsignedp || $3.unsignedp; } |
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| 317 | | exp '^' exp |
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| 318 | { $$.value = $1.value ^ $3.value; |
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| 319 | $$.unsignedp = $1.unsignedp || $3.unsignedp; } |
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| 320 | | exp '|' exp |
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| 321 | { $$.value = $1.value | $3.value; |
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| 322 | $$.unsignedp = $1.unsignedp || $3.unsignedp; } |
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| 323 | | exp AND |
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| 324 | { skip_evaluation += !$1.value; } |
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| 325 | exp |
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| 326 | { skip_evaluation -= !$1.value; |
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| 327 | $$.value = ($1.value && $4.value); |
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| 328 | $$.unsignedp = 0; } |
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| 329 | | exp OR |
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| 330 | { skip_evaluation += !!$1.value; } |
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| 331 | exp |
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| 332 | { skip_evaluation -= !!$1.value; |
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| 333 | $$.value = ($1.value || $4.value); |
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| 334 | $$.unsignedp = 0; } |
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| 335 | | exp '?' |
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| 336 | { skip_evaluation += !$1.value; } |
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| 337 | exp ':' |
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| 338 | { skip_evaluation += !!$1.value - !$1.value; } |
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| 339 | exp |
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| 340 | { skip_evaluation -= !!$1.value; |
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| 341 | $$.value = $1.value ? $4.value : $7.value; |
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| 342 | $$.unsignedp = $4.unsignedp || $7.unsignedp; } |
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| 343 | | INT |
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| 344 | { $$ = yylval.integer; } |
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| 345 | | CHAR |
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| 346 | { $$ = yylval.integer; } |
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| 347 | | NAME |
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| 348 | { $$.value = 0; |
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| 349 | $$.unsignedp = 0; } |
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| 350 | ; |
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| 351 | |
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| 352 | keywords : |
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| 353 | { $$ = 0; } |
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| 354 | | '(' keywords ')' keywords |
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| 355 | { struct arglist *temp; |
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| 356 | $$ = (struct arglist *) xmalloc (sizeof (struct arglist)); |
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| 357 | $$->next = $2; |
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| 358 | $$->name = (U_CHAR *) "("; |
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| 359 | $$->length = 1; |
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| 360 | temp = $$; |
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| 361 | while (temp != 0 && temp->next != 0) |
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| 362 | temp = temp->next; |
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| 363 | temp->next = (struct arglist *) xmalloc (sizeof (struct arglist)); |
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| 364 | temp->next->next = $4; |
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| 365 | temp->next->name = (U_CHAR *) ")"; |
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| 366 | temp->next->length = 1; } |
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| 367 | | NAME keywords |
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| 368 | { $$ = (struct arglist *) xmalloc (sizeof (struct arglist)); |
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| 369 | $$->name = $1.address; |
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| 370 | $$->length = $1.length; |
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| 371 | $$->next = $2; } |
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| 372 | ; |
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| 373 | %% |
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| 374 | |
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| 375 | /* During parsing of a C expression, the pointer to the next character |
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| 376 | is in this variable. */ |
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| 377 | |
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| 378 | static char *lexptr; |
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| 379 | |
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| 380 | /* Take care of parsing a number (anything that starts with a digit). |
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| 381 | Set yylval and return the token type; update lexptr. |
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| 382 | LEN is the number of characters in it. */ |
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| 383 | |
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| 384 | /* maybe needs to actually deal with floating point numbers */ |
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| 385 | |
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| 386 | int |
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| 387 | parse_number (olen) |
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| 388 | int olen; |
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| 389 | { |
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| 390 | register char *p = lexptr; |
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| 391 | register int c; |
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| 392 | register unsigned long n = 0, nd, ULONG_MAX_over_base; |
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| 393 | register int base = 10; |
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| 394 | register int len = olen; |
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| 395 | register int overflow = 0; |
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| 396 | register int digit, largest_digit = 0; |
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| 397 | int spec_long = 0; |
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| 398 | |
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| 399 | for (c = 0; c < len; c++) |
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| 400 | if (p[c] == '.') { |
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| 401 | /* It's a float since it contains a point. */ |
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| 402 | yyerror ("floating point numbers not allowed in #if expressions"); |
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| 403 | return ERROR; |
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| 404 | } |
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| 405 | |
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| 406 | yylval.integer.unsignedp = 0; |
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| 407 | |
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| 408 | if (len >= 3 && (!strncmp (p, "0x", 2) || !strncmp (p, "0X", 2))) { |
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| 409 | p += 2; |
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| 410 | base = 16; |
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| 411 | len -= 2; |
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| 412 | } |
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| 413 | else if (*p == '0') |
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| 414 | base = 8; |
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| 415 | |
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| 416 | ULONG_MAX_over_base = (unsigned long) -1 / base; |
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| 417 | |
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| 418 | for (; len > 0; len--) { |
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| 419 | c = *p++; |
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| 420 | |
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| 421 | if (c >= '0' && c <= '9') |
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| 422 | digit = c - '0'; |
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| 423 | else if (base == 16 && c >= 'a' && c <= 'f') |
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| 424 | digit = c - 'a' + 10; |
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| 425 | else if (base == 16 && c >= 'A' && c <= 'F') |
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| 426 | digit = c - 'A' + 10; |
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| 427 | else { |
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| 428 | /* `l' means long, and `u' means unsigned. */ |
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| 429 | while (1) { |
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| 430 | if (c == 'l' || c == 'L') |
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| 431 | { |
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| 432 | if (spec_long) |
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| 433 | yyerror ("two `l's in integer constant"); |
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| 434 | spec_long = 1; |
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| 435 | } |
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| 436 | else if (c == 'u' || c == 'U') |
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| 437 | { |
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| 438 | if (yylval.integer.unsignedp) |
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| 439 | yyerror ("two `u's in integer constant"); |
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| 440 | yylval.integer.unsignedp = 1; |
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| 441 | } |
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| 442 | else |
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| 443 | break; |
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| 444 | |
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| 445 | if (--len == 0) |
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| 446 | break; |
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| 447 | c = *p++; |
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| 448 | } |
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| 449 | /* Don't look for any more digits after the suffixes. */ |
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| 450 | break; |
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| 451 | } |
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| 452 | if (largest_digit < digit) |
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| 453 | largest_digit = digit; |
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| 454 | nd = n * base + digit; |
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| 455 | overflow |= ULONG_MAX_over_base < n | nd < n; |
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| 456 | n = nd; |
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| 457 | } |
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| 458 | |
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| 459 | if (len != 0) { |
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| 460 | yyerror ("Invalid number in #if expression"); |
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| 461 | return ERROR; |
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| 462 | } |
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| 463 | |
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| 464 | if (base <= largest_digit) |
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| 465 | warning ("integer constant contains digits beyond the radix"); |
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| 466 | |
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| 467 | if (overflow) |
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| 468 | warning ("integer constant out of range"); |
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| 469 | |
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| 470 | /* If too big to be signed, consider it unsigned. */ |
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| 471 | if ((long) n < 0 && ! yylval.integer.unsignedp) |
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| 472 | { |
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| 473 | if (base == 10) |
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| 474 | warning ("integer constant is so large that it is unsigned"); |
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| 475 | yylval.integer.unsignedp = 1; |
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| 476 | } |
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| 477 | |
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| 478 | lexptr = p; |
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| 479 | yylval.integer.value = n; |
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| 480 | return INT; |
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| 481 | } |
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| 482 | |
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| 483 | struct token { |
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| 484 | char *operator; |
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| 485 | int token; |
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| 486 | }; |
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| 487 | |
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| 488 | static struct token tokentab2[] = { |
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| 489 | {"&&", AND}, |
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| 490 | {"||", OR}, |
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| 491 | {"<<", LSH}, |
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| 492 | {">>", RSH}, |
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| 493 | {"==", EQUAL}, |
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| 494 | {"!=", NOTEQUAL}, |
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| 495 | {"<=", LEQ}, |
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| 496 | {">=", GEQ}, |
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| 497 | {"++", ERROR}, |
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| 498 | {"--", ERROR}, |
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| 499 | {NULL, ERROR} |
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| 500 | }; |
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| 501 | |
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| 502 | /* Read one token, getting characters through lexptr. */ |
---|
| 503 | |
---|
| 504 | int |
---|
| 505 | yylex () |
---|
| 506 | { |
---|
| 507 | register int c; |
---|
| 508 | register int namelen; |
---|
| 509 | register unsigned char *tokstart; |
---|
| 510 | register struct token *toktab; |
---|
| 511 | int wide_flag; |
---|
| 512 | |
---|
| 513 | retry: |
---|
| 514 | |
---|
| 515 | tokstart = (unsigned char *) lexptr; |
---|
| 516 | c = *tokstart; |
---|
| 517 | /* See if it is a special token of length 2. */ |
---|
| 518 | if (! keyword_parsing) |
---|
| 519 | for (toktab = tokentab2; toktab->operator != NULL; toktab++) |
---|
| 520 | if (c == *toktab->operator && tokstart[1] == toktab->operator[1]) { |
---|
| 521 | lexptr += 2; |
---|
| 522 | if (toktab->token == ERROR) |
---|
| 523 | { |
---|
| 524 | char *buf = (char *) alloca (40); |
---|
| 525 | sprintf (buf, "`%s' not allowed in operand of `#if'", toktab->operator); |
---|
| 526 | yyerror (buf); |
---|
| 527 | } |
---|
| 528 | return toktab->token; |
---|
| 529 | } |
---|
| 530 | |
---|
| 531 | switch (c) { |
---|
| 532 | case 0: |
---|
| 533 | return 0; |
---|
| 534 | |
---|
| 535 | case ' ': |
---|
| 536 | case '\t': |
---|
| 537 | case '\r': |
---|
| 538 | case '\n': |
---|
| 539 | lexptr++; |
---|
| 540 | goto retry; |
---|
| 541 | |
---|
| 542 | case 'L': |
---|
| 543 | /* Capital L may start a wide-string or wide-character constant. */ |
---|
| 544 | if (lexptr[1] == '\'') |
---|
| 545 | { |
---|
| 546 | lexptr++; |
---|
| 547 | wide_flag = 1; |
---|
| 548 | goto char_constant; |
---|
| 549 | } |
---|
| 550 | if (lexptr[1] == '"') |
---|
| 551 | { |
---|
| 552 | lexptr++; |
---|
| 553 | wide_flag = 1; |
---|
| 554 | goto string_constant; |
---|
| 555 | } |
---|
| 556 | break; |
---|
| 557 | |
---|
| 558 | case '\'': |
---|
| 559 | wide_flag = 0; |
---|
| 560 | char_constant: |
---|
| 561 | lexptr++; |
---|
| 562 | if (keyword_parsing) { |
---|
| 563 | char *start_ptr = lexptr - 1; |
---|
| 564 | while (1) { |
---|
| 565 | c = *lexptr++; |
---|
| 566 | if (c == '\\') |
---|
| 567 | c = parse_escape (&lexptr); |
---|
| 568 | else if (c == '\'') |
---|
| 569 | break; |
---|
| 570 | } |
---|
| 571 | yylval.name.address = tokstart; |
---|
| 572 | yylval.name.length = lexptr - start_ptr; |
---|
| 573 | return NAME; |
---|
| 574 | } |
---|
| 575 | |
---|
| 576 | /* This code for reading a character constant |
---|
| 577 | handles multicharacter constants and wide characters. |
---|
| 578 | It is mostly copied from c-lex.c. */ |
---|
| 579 | { |
---|
| 580 | register int result = 0; |
---|
| 581 | register num_chars = 0; |
---|
| 582 | unsigned width = MAX_CHAR_TYPE_SIZE; |
---|
| 583 | int max_chars; |
---|
| 584 | char *token_buffer; |
---|
| 585 | |
---|
| 586 | if (wide_flag) |
---|
| 587 | { |
---|
| 588 | width = MAX_WCHAR_TYPE_SIZE; |
---|
| 589 | #ifdef MULTIBYTE_CHARS |
---|
| 590 | max_chars = MB_CUR_MAX; |
---|
| 591 | #else |
---|
| 592 | max_chars = 1; |
---|
| 593 | #endif |
---|
| 594 | } |
---|
| 595 | else |
---|
| 596 | max_chars = MAX_LONG_TYPE_SIZE / width; |
---|
| 597 | |
---|
| 598 | token_buffer = (char *) alloca (max_chars + 1); |
---|
| 599 | |
---|
| 600 | while (1) |
---|
| 601 | { |
---|
| 602 | c = *lexptr++; |
---|
| 603 | |
---|
| 604 | if (c == '\'' || c == EOF) |
---|
| 605 | break; |
---|
| 606 | |
---|
| 607 | if (c == '\\') |
---|
| 608 | { |
---|
| 609 | c = parse_escape (&lexptr); |
---|
| 610 | if (width < HOST_BITS_PER_INT |
---|
| 611 | && (unsigned) c >= (1 << width)) |
---|
| 612 | pedwarn ("escape sequence out of range for character"); |
---|
| 613 | } |
---|
| 614 | |
---|
| 615 | num_chars++; |
---|
| 616 | |
---|
| 617 | /* Merge character into result; ignore excess chars. */ |
---|
| 618 | if (num_chars < max_chars + 1) |
---|
| 619 | { |
---|
| 620 | if (width < HOST_BITS_PER_INT) |
---|
| 621 | result = (result << width) | (c & ((1 << width) - 1)); |
---|
| 622 | else |
---|
| 623 | result = c; |
---|
| 624 | token_buffer[num_chars - 1] = c; |
---|
| 625 | } |
---|
| 626 | } |
---|
| 627 | |
---|
| 628 | token_buffer[num_chars] = 0; |
---|
| 629 | |
---|
| 630 | if (c != '\'') |
---|
| 631 | error ("malformatted character constant"); |
---|
| 632 | else if (num_chars == 0) |
---|
| 633 | error ("empty character constant"); |
---|
| 634 | else if (num_chars > max_chars) |
---|
| 635 | { |
---|
| 636 | num_chars = max_chars; |
---|
| 637 | error ("character constant too long"); |
---|
| 638 | } |
---|
| 639 | else if (num_chars != 1 && ! traditional) |
---|
| 640 | warning ("multi-character character constant"); |
---|
| 641 | |
---|
| 642 | /* If char type is signed, sign-extend the constant. */ |
---|
| 643 | if (! wide_flag) |
---|
| 644 | { |
---|
| 645 | int num_bits = num_chars * width; |
---|
| 646 | |
---|
| 647 | if (lookup ("__CHAR_UNSIGNED__", sizeof ("__CHAR_UNSIGNED__")-1, -1) |
---|
| 648 | || ((result >> (num_bits - 1)) & 1) == 0) |
---|
| 649 | yylval.integer.value |
---|
| 650 | = result & ((unsigned long) ~0 >> (HOST_BITS_PER_LONG - num_bits)); |
---|
| 651 | else |
---|
| 652 | yylval.integer.value |
---|
| 653 | = result | ~((unsigned long) ~0 >> (HOST_BITS_PER_LONG - num_bits)); |
---|
| 654 | } |
---|
| 655 | else |
---|
| 656 | { |
---|
| 657 | #ifdef MULTIBYTE_CHARS |
---|
| 658 | /* Set the initial shift state and convert the next sequence. */ |
---|
| 659 | result = 0; |
---|
| 660 | /* In all locales L'\0' is zero and mbtowc will return zero, |
---|
| 661 | so don't use it. */ |
---|
| 662 | if (num_chars > 1 |
---|
| 663 | || (num_chars == 1 && token_buffer[0] != '\0')) |
---|
| 664 | { |
---|
| 665 | wchar_t wc; |
---|
| 666 | (void) mbtowc (NULL_PTR, NULL_PTR, 0); |
---|
| 667 | if (mbtowc (& wc, token_buffer, num_chars) == num_chars) |
---|
| 668 | result = wc; |
---|
| 669 | else |
---|
| 670 | warning ("Ignoring invalid multibyte character"); |
---|
| 671 | } |
---|
| 672 | #endif |
---|
| 673 | yylval.integer.value = result; |
---|
| 674 | } |
---|
| 675 | } |
---|
| 676 | |
---|
| 677 | /* This is always a signed type. */ |
---|
| 678 | yylval.integer.unsignedp = 0; |
---|
| 679 | |
---|
| 680 | return CHAR; |
---|
| 681 | |
---|
| 682 | /* some of these chars are invalid in constant expressions; |
---|
| 683 | maybe do something about them later */ |
---|
| 684 | case '/': |
---|
| 685 | case '+': |
---|
| 686 | case '-': |
---|
| 687 | case '*': |
---|
| 688 | case '%': |
---|
| 689 | case '|': |
---|
| 690 | case '&': |
---|
| 691 | case '^': |
---|
| 692 | case '~': |
---|
| 693 | case '!': |
---|
| 694 | case '@': |
---|
| 695 | case '<': |
---|
| 696 | case '>': |
---|
| 697 | case '[': |
---|
| 698 | case ']': |
---|
| 699 | case '.': |
---|
| 700 | case '?': |
---|
| 701 | case ':': |
---|
| 702 | case '=': |
---|
| 703 | case '{': |
---|
| 704 | case '}': |
---|
| 705 | case ',': |
---|
| 706 | case '#': |
---|
| 707 | if (keyword_parsing) |
---|
| 708 | break; |
---|
| 709 | case '(': |
---|
| 710 | case ')': |
---|
| 711 | lexptr++; |
---|
| 712 | return c; |
---|
| 713 | |
---|
| 714 | case '"': |
---|
| 715 | string_constant: |
---|
| 716 | if (keyword_parsing) { |
---|
| 717 | char *start_ptr = lexptr; |
---|
| 718 | lexptr++; |
---|
| 719 | while (1) { |
---|
| 720 | c = *lexptr++; |
---|
| 721 | if (c == '\\') |
---|
| 722 | c = parse_escape (&lexptr); |
---|
| 723 | else if (c == '"') |
---|
| 724 | break; |
---|
| 725 | } |
---|
| 726 | yylval.name.address = tokstart; |
---|
| 727 | yylval.name.length = lexptr - start_ptr; |
---|
| 728 | return NAME; |
---|
| 729 | } |
---|
| 730 | yyerror ("string constants not allowed in #if expressions"); |
---|
| 731 | return ERROR; |
---|
| 732 | } |
---|
| 733 | |
---|
| 734 | if (c >= '0' && c <= '9' && !keyword_parsing) { |
---|
| 735 | /* It's a number */ |
---|
| 736 | for (namelen = 0; |
---|
| 737 | c = tokstart[namelen], is_idchar[c] || c == '.'; |
---|
| 738 | namelen++) |
---|
| 739 | ; |
---|
| 740 | return parse_number (namelen); |
---|
| 741 | } |
---|
| 742 | |
---|
| 743 | /* It is a name. See how long it is. */ |
---|
| 744 | |
---|
| 745 | if (keyword_parsing) { |
---|
| 746 | for (namelen = 0;; namelen++) { |
---|
| 747 | if (is_hor_space[tokstart[namelen]]) |
---|
| 748 | break; |
---|
| 749 | if (tokstart[namelen] == '(' || tokstart[namelen] == ')') |
---|
| 750 | break; |
---|
| 751 | if (tokstart[namelen] == '"' || tokstart[namelen] == '\'') |
---|
| 752 | break; |
---|
| 753 | } |
---|
| 754 | } else { |
---|
| 755 | if (!is_idstart[c]) { |
---|
| 756 | yyerror ("Invalid token in expression"); |
---|
| 757 | return ERROR; |
---|
| 758 | } |
---|
| 759 | |
---|
| 760 | for (namelen = 0; is_idchar[tokstart[namelen]]; namelen++) |
---|
| 761 | ; |
---|
| 762 | } |
---|
| 763 | |
---|
| 764 | lexptr += namelen; |
---|
| 765 | yylval.name.address = tokstart; |
---|
| 766 | yylval.name.length = namelen; |
---|
| 767 | return NAME; |
---|
| 768 | } |
---|
| 769 | |
---|
| 770 | |
---|
| 771 | /* Parse a C escape sequence. STRING_PTR points to a variable |
---|
| 772 | containing a pointer to the string to parse. That pointer |
---|
| 773 | is updated past the characters we use. The value of the |
---|
| 774 | escape sequence is returned. |
---|
| 775 | |
---|
| 776 | A negative value means the sequence \ newline was seen, |
---|
| 777 | which is supposed to be equivalent to nothing at all. |
---|
| 778 | |
---|
| 779 | If \ is followed by a null character, we return a negative |
---|
| 780 | value and leave the string pointer pointing at the null character. |
---|
| 781 | |
---|
| 782 | If \ is followed by 000, we return 0 and leave the string pointer |
---|
| 783 | after the zeros. A value of 0 does not mean end of string. */ |
---|
| 784 | |
---|
| 785 | int |
---|
| 786 | parse_escape (string_ptr) |
---|
| 787 | char **string_ptr; |
---|
| 788 | { |
---|
| 789 | register int c = *(*string_ptr)++; |
---|
| 790 | switch (c) |
---|
| 791 | { |
---|
| 792 | case 'a': |
---|
| 793 | return TARGET_BELL; |
---|
| 794 | case 'b': |
---|
| 795 | return TARGET_BS; |
---|
| 796 | case 'e': |
---|
| 797 | case 'E': |
---|
| 798 | if (pedantic) |
---|
| 799 | pedwarn ("non-ANSI-standard escape sequence, `\\%c'", c); |
---|
| 800 | return 033; |
---|
| 801 | case 'f': |
---|
| 802 | return TARGET_FF; |
---|
| 803 | case 'n': |
---|
| 804 | return TARGET_NEWLINE; |
---|
| 805 | case 'r': |
---|
| 806 | return TARGET_CR; |
---|
| 807 | case 't': |
---|
| 808 | return TARGET_TAB; |
---|
| 809 | case 'v': |
---|
| 810 | return TARGET_VT; |
---|
| 811 | case '\n': |
---|
| 812 | return -2; |
---|
| 813 | case 0: |
---|
| 814 | (*string_ptr)--; |
---|
| 815 | return 0; |
---|
| 816 | |
---|
| 817 | case '0': |
---|
| 818 | case '1': |
---|
| 819 | case '2': |
---|
| 820 | case '3': |
---|
| 821 | case '4': |
---|
| 822 | case '5': |
---|
| 823 | case '6': |
---|
| 824 | case '7': |
---|
| 825 | { |
---|
| 826 | register int i = c - '0'; |
---|
| 827 | register int count = 0; |
---|
| 828 | while (++count < 3) |
---|
| 829 | { |
---|
| 830 | c = *(*string_ptr)++; |
---|
| 831 | if (c >= '0' && c <= '7') |
---|
| 832 | i = (i << 3) + c - '0'; |
---|
| 833 | else |
---|
| 834 | { |
---|
| 835 | (*string_ptr)--; |
---|
| 836 | break; |
---|
| 837 | } |
---|
| 838 | } |
---|
| 839 | if ((i & ~((1 << MAX_CHAR_TYPE_SIZE) - 1)) != 0) |
---|
| 840 | { |
---|
| 841 | i &= (1 << MAX_CHAR_TYPE_SIZE) - 1; |
---|
| 842 | warning ("octal character constant does not fit in a byte"); |
---|
| 843 | } |
---|
| 844 | return i; |
---|
| 845 | } |
---|
| 846 | case 'x': |
---|
| 847 | { |
---|
| 848 | register unsigned i = 0, overflow = 0, digits_found = 0, digit; |
---|
| 849 | for (;;) |
---|
| 850 | { |
---|
| 851 | c = *(*string_ptr)++; |
---|
| 852 | if (c >= '0' && c <= '9') |
---|
| 853 | digit = c - '0'; |
---|
| 854 | else if (c >= 'a' && c <= 'f') |
---|
| 855 | digit = c - 'a' + 10; |
---|
| 856 | else if (c >= 'A' && c <= 'F') |
---|
| 857 | digit = c - 'A' + 10; |
---|
| 858 | else |
---|
| 859 | { |
---|
| 860 | (*string_ptr)--; |
---|
| 861 | break; |
---|
| 862 | } |
---|
| 863 | overflow |= i ^ (i << 4 >> 4); |
---|
| 864 | i = (i << 4) + digit; |
---|
| 865 | digits_found = 1; |
---|
| 866 | } |
---|
| 867 | if (!digits_found) |
---|
| 868 | yyerror ("\\x used with no following hex digits"); |
---|
| 869 | if (overflow | (i & ~((1 << BITS_PER_UNIT) - 1))) |
---|
| 870 | { |
---|
| 871 | i &= (1 << BITS_PER_UNIT) - 1; |
---|
| 872 | warning ("hex character constant does not fit in a byte"); |
---|
| 873 | } |
---|
| 874 | return i; |
---|
| 875 | } |
---|
| 876 | default: |
---|
| 877 | return c; |
---|
| 878 | } |
---|
| 879 | } |
---|
| 880 | |
---|
| 881 | void |
---|
| 882 | yyerror (s) |
---|
| 883 | char *s; |
---|
| 884 | { |
---|
| 885 | error (s); |
---|
| 886 | skip_evaluation = 0; |
---|
| 887 | longjmp (parse_return_error, 1); |
---|
| 888 | } |
---|
| 889 | |
---|
| 890 | static void |
---|
| 891 | integer_overflow () |
---|
| 892 | { |
---|
| 893 | if (!skip_evaluation && pedantic) |
---|
| 894 | pedwarn ("integer overflow in preprocessor expression"); |
---|
| 895 | } |
---|
| 896 | |
---|
| 897 | static long |
---|
| 898 | left_shift (a, b) |
---|
| 899 | struct constant *a; |
---|
| 900 | unsigned long b; |
---|
| 901 | { |
---|
| 902 | /* It's unclear from the C standard whether shifts can overflow. |
---|
| 903 | The following code ignores overflow; perhaps a C standard |
---|
| 904 | interpretation ruling is needed. */ |
---|
| 905 | if (b >= HOST_BITS_PER_LONG) |
---|
| 906 | return 0; |
---|
| 907 | else if (a->unsignedp) |
---|
| 908 | return (unsigned long) a->value << b; |
---|
| 909 | else |
---|
| 910 | return a->value << b; |
---|
| 911 | } |
---|
| 912 | |
---|
| 913 | static long |
---|
| 914 | right_shift (a, b) |
---|
| 915 | struct constant *a; |
---|
| 916 | unsigned long b; |
---|
| 917 | { |
---|
| 918 | if (b >= HOST_BITS_PER_LONG) |
---|
| 919 | return a->unsignedp ? 0 : a->value >> (HOST_BITS_PER_LONG - 1); |
---|
| 920 | else if (a->unsignedp) |
---|
| 921 | return (unsigned long) a->value >> b; |
---|
| 922 | else |
---|
| 923 | return a->value >> b; |
---|
| 924 | } |
---|
| 925 | |
---|
| 926 | /* This page contains the entry point to this file. */ |
---|
| 927 | |
---|
| 928 | /* Parse STRING as an expression, and complain if this fails |
---|
| 929 | to use up all of the contents of STRING. */ |
---|
| 930 | /* We do not support C comments. They should be removed before |
---|
| 931 | this function is called. */ |
---|
| 932 | |
---|
| 933 | HOST_WIDE_INT |
---|
| 934 | parse_c_expression (string) |
---|
| 935 | char *string; |
---|
| 936 | { |
---|
| 937 | lexptr = string; |
---|
| 938 | |
---|
| 939 | if (lexptr == 0 || *lexptr == 0) { |
---|
| 940 | error ("empty #if expression"); |
---|
| 941 | return 0; /* don't include the #if group */ |
---|
| 942 | } |
---|
| 943 | |
---|
| 944 | /* if there is some sort of scanning error, just return 0 and assume |
---|
| 945 | the parsing routine has printed an error message somewhere. |
---|
| 946 | there is surely a better thing to do than this. */ |
---|
| 947 | if (setjmp (parse_return_error)) |
---|
| 948 | return 0; |
---|
| 949 | |
---|
| 950 | if (yyparse ()) |
---|
| 951 | return 0; /* actually this is never reached |
---|
| 952 | the way things stand. */ |
---|
| 953 | if (*lexptr) |
---|
| 954 | error ("Junk after end of expression."); |
---|
| 955 | |
---|
| 956 | return expression_value; /* set by yyparse () */ |
---|
| 957 | } |
---|
| 958 | |
---|
| 959 | #ifdef TEST_EXP_READER |
---|
| 960 | extern int yydebug; |
---|
| 961 | |
---|
| 962 | /* Main program for testing purposes. */ |
---|
| 963 | int |
---|
| 964 | main () |
---|
| 965 | { |
---|
| 966 | int n, c; |
---|
| 967 | char buf[1024]; |
---|
| 968 | |
---|
| 969 | /* |
---|
| 970 | yydebug = 1; |
---|
| 971 | */ |
---|
| 972 | initialize_random_junk (); |
---|
| 973 | |
---|
| 974 | for (;;) { |
---|
| 975 | printf ("enter expression: "); |
---|
| 976 | n = 0; |
---|
| 977 | while ((buf[n] = getchar ()) != '\n' && buf[n] != EOF) |
---|
| 978 | n++; |
---|
| 979 | if (buf[n] == EOF) |
---|
| 980 | break; |
---|
| 981 | buf[n] = '\0'; |
---|
| 982 | printf ("parser returned %ld\n", parse_c_expression (buf)); |
---|
| 983 | } |
---|
| 984 | |
---|
| 985 | return 0; |
---|
| 986 | } |
---|
| 987 | |
---|
| 988 | /* table to tell if char can be part of a C identifier. */ |
---|
| 989 | unsigned char is_idchar[256]; |
---|
| 990 | /* table to tell if char can be first char of a c identifier. */ |
---|
| 991 | unsigned char is_idstart[256]; |
---|
| 992 | /* table to tell if c is horizontal space. isspace () thinks that |
---|
| 993 | newline is space; this is not a good idea for this program. */ |
---|
| 994 | char is_hor_space[256]; |
---|
| 995 | |
---|
| 996 | /* |
---|
| 997 | * initialize random junk in the hash table and maybe other places |
---|
| 998 | */ |
---|
| 999 | initialize_random_junk () |
---|
| 1000 | { |
---|
| 1001 | register int i; |
---|
| 1002 | |
---|
| 1003 | /* |
---|
| 1004 | * Set up is_idchar and is_idstart tables. These should be |
---|
| 1005 | * faster than saying (is_alpha (c) || c == '_'), etc. |
---|
| 1006 | * Must do set up these things before calling any routines tthat |
---|
| 1007 | * refer to them. |
---|
| 1008 | */ |
---|
| 1009 | for (i = 'a'; i <= 'z'; i++) { |
---|
| 1010 | ++is_idchar[i - 'a' + 'A']; |
---|
| 1011 | ++is_idchar[i]; |
---|
| 1012 | ++is_idstart[i - 'a' + 'A']; |
---|
| 1013 | ++is_idstart[i]; |
---|
| 1014 | } |
---|
| 1015 | for (i = '0'; i <= '9'; i++) |
---|
| 1016 | ++is_idchar[i]; |
---|
| 1017 | ++is_idchar['_']; |
---|
| 1018 | ++is_idstart['_']; |
---|
| 1019 | #if DOLLARS_IN_IDENTIFIERS |
---|
| 1020 | ++is_idchar['$']; |
---|
| 1021 | ++is_idstart['$']; |
---|
| 1022 | #endif |
---|
| 1023 | |
---|
| 1024 | /* horizontal space table */ |
---|
| 1025 | ++is_hor_space[' ']; |
---|
| 1026 | ++is_hor_space['\t']; |
---|
| 1027 | } |
---|
| 1028 | |
---|
| 1029 | error (msg) |
---|
| 1030 | { |
---|
| 1031 | printf ("error: %s\n", msg); |
---|
| 1032 | } |
---|
| 1033 | |
---|
| 1034 | warning (msg) |
---|
| 1035 | { |
---|
| 1036 | printf ("warning: %s\n", msg); |
---|
| 1037 | } |
---|
| 1038 | |
---|
| 1039 | struct hashnode * |
---|
| 1040 | lookup (name, len, hash) |
---|
| 1041 | char *name; |
---|
| 1042 | int len; |
---|
| 1043 | int hash; |
---|
| 1044 | { |
---|
| 1045 | return (DEFAULT_SIGNED_CHAR) ? 0 : ((struct hashnode *) -1); |
---|
| 1046 | } |
---|
| 1047 | #endif |
---|