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b0699dad | 1 | /* Parse C expressions for cpplib. |
525bc95d | 2 | Copyright (C) 1987, 92, 94, 95, 97, 98, 1999, 2000 Free Software Foundation. |
7f2935c7 PB |
3 | |
4 | This program is free software; you can redistribute it and/or modify it | |
5 | under the terms of the GNU General Public License as published by the | |
6 | Free Software Foundation; either version 2, or (at your option) any | |
7 | later version. | |
8 | ||
9 | This program is distributed in the hope that it will be useful, | |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | GNU General Public License for more details. | |
13 | ||
14 | You should have received a copy of the GNU General Public License | |
15 | along with this program; if not, write to the Free Software | |
940d9d63 RK |
16 | Foundation, 59 Temple Place - Suite 330, |
17 | Boston, MA 02111-1307, USA. | |
7f2935c7 PB |
18 | |
19 | In other words, you are welcome to use, share and improve this program. | |
20 | You are forbidden to forbid anyone else to use, share and improve | |
21 | what you give them. Help stamp out software-hoarding! | |
22 | ||
0f41302f | 23 | Written by Per Bothner 1994. */ |
7f2935c7 PB |
24 | |
25 | /* Parse a C expression from text in a string */ | |
26 | ||
27 | #include "config.h" | |
b04cd507 | 28 | #include "system.h" |
487a6e06 | 29 | #include "cpplib.h" |
7f2935c7 | 30 | |
9870475c | 31 | #ifdef MULTIBYTE_CHARS |
7f2935c7 PB |
32 | #include <locale.h> |
33 | #endif | |
34 | ||
7f2935c7 PB |
35 | #ifndef CHAR_TYPE_SIZE |
36 | #define CHAR_TYPE_SIZE BITS_PER_UNIT | |
37 | #endif | |
38 | ||
39 | #ifndef INT_TYPE_SIZE | |
40 | #define INT_TYPE_SIZE BITS_PER_WORD | |
41 | #endif | |
42 | ||
43 | #ifndef LONG_TYPE_SIZE | |
44 | #define LONG_TYPE_SIZE BITS_PER_WORD | |
45 | #endif | |
46 | ||
47 | #ifndef WCHAR_TYPE_SIZE | |
48 | #define WCHAR_TYPE_SIZE INT_TYPE_SIZE | |
49 | #endif | |
50 | ||
51 | #ifndef MAX_CHAR_TYPE_SIZE | |
52 | #define MAX_CHAR_TYPE_SIZE CHAR_TYPE_SIZE | |
53 | #endif | |
54 | ||
55 | #ifndef MAX_INT_TYPE_SIZE | |
56 | #define MAX_INT_TYPE_SIZE INT_TYPE_SIZE | |
57 | #endif | |
58 | ||
59 | #ifndef MAX_LONG_TYPE_SIZE | |
60 | #define MAX_LONG_TYPE_SIZE LONG_TYPE_SIZE | |
61 | #endif | |
62 | ||
63 | #ifndef MAX_WCHAR_TYPE_SIZE | |
64 | #define MAX_WCHAR_TYPE_SIZE WCHAR_TYPE_SIZE | |
65 | #endif | |
66 | ||
e915b770 | 67 | #define MAX_CHAR_TYPE_MASK (MAX_CHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \ |
b0699dad | 68 | ? (~(~(HOST_WIDEST_INT) 0 << MAX_CHAR_TYPE_SIZE)) \ |
e915b770 | 69 | : ~ (HOST_WIDEST_INT) 0) |
f1a86df6 | 70 | |
e915b770 | 71 | #define MAX_WCHAR_TYPE_MASK (MAX_WCHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \ |
b0699dad | 72 | ? ~(~(HOST_WIDEST_INT) 0 << MAX_WCHAR_TYPE_SIZE) \ |
e915b770 | 73 | : ~ (HOST_WIDEST_INT) 0) |
f1a86df6 | 74 | |
7f2935c7 PB |
75 | /* Yield nonzero if adding two numbers with A's and B's signs can yield a |
76 | number with SUM's sign, where A, B, and SUM are all C integers. */ | |
77 | #define possible_sum_sign(a, b, sum) ((((a) ^ (b)) | ~ ((a) ^ (sum))) < 0) | |
78 | ||
b04cd507 | 79 | static void integer_overflow PARAMS ((cpp_reader *)); |
b0699dad | 80 | static HOST_WIDEST_INT left_shift PARAMS ((cpp_reader *, HOST_WIDEST_INT, |
e23c0ba3 ZW |
81 | unsigned int, |
82 | unsigned HOST_WIDEST_INT)); | |
b0699dad | 83 | static HOST_WIDEST_INT right_shift PARAMS ((cpp_reader *, HOST_WIDEST_INT, |
e23c0ba3 ZW |
84 | unsigned int, |
85 | unsigned HOST_WIDEST_INT)); | |
b0699dad ZW |
86 | static struct operation parse_number PARAMS ((cpp_reader *, U_CHAR *, |
87 | U_CHAR *)); | |
88 | static struct operation parse_charconst PARAMS ((cpp_reader *, U_CHAR *, | |
89 | U_CHAR *)); | |
ba412f14 | 90 | static struct operation parse_defined PARAMS ((cpp_reader *)); |
b0699dad ZW |
91 | static HOST_WIDEST_INT parse_escape PARAMS ((cpp_reader *, U_CHAR **, |
92 | HOST_WIDEST_INT)); | |
93 | static struct operation lex PARAMS ((cpp_reader *, int)); | |
94 | ||
7f2935c7 PB |
95 | |
96 | #define ERROR 299 | |
97 | #define OROR 300 | |
98 | #define ANDAND 301 | |
99 | #define EQUAL 302 | |
100 | #define NOTEQUAL 303 | |
101 | #define LEQ 304 | |
102 | #define GEQ 305 | |
103 | #define LSH 306 | |
104 | #define RSH 307 | |
105 | #define NAME 308 | |
106 | #define INT 309 | |
107 | #define CHAR 310 | |
108 | ||
109 | #define LEFT_OPERAND_REQUIRED 1 | |
110 | #define RIGHT_OPERAND_REQUIRED 2 | |
111 | #define HAVE_VALUE 4 | |
a4a315ef | 112 | /* SKIP_OPERAND is set for '&&' '||' '?' and ':' when the |
0f41302f | 113 | following operand should be short-circuited instead of evaluated. */ |
a4a315ef | 114 | #define SKIP_OPERAND 8 |
7f2935c7 | 115 | |
b0699dad ZW |
116 | struct operation |
117 | { | |
118 | short op; | |
e23c0ba3 ZW |
119 | U_CHAR rprio; /* Priority of op (relative to it right operand). */ |
120 | U_CHAR flags; | |
121 | U_CHAR unsignedp; /* true if value should be treated as unsigned */ | |
b0699dad | 122 | HOST_WIDEST_INT value; /* The value logically "right" of op. */ |
7f2935c7 | 123 | }; |
7f2935c7 | 124 | |
f13eb63a ZW |
125 | /* Parse and convert an integer for #if. Accepts decimal, hex, or octal |
126 | with or without size suffixes. */ | |
7f2935c7 | 127 | |
f13eb63a ZW |
128 | static struct operation |
129 | parse_number (pfile, start, end) | |
7f2935c7 | 130 | cpp_reader *pfile; |
f13eb63a ZW |
131 | U_CHAR *start; |
132 | U_CHAR *end; | |
7f2935c7 PB |
133 | { |
134 | struct operation op; | |
f13eb63a ZW |
135 | U_CHAR *p = start; |
136 | int c; | |
e915b770 | 137 | unsigned HOST_WIDEST_INT n = 0, nd, MAX_over_base; |
f13eb63a ZW |
138 | int base = 10; |
139 | int overflow = 0; | |
140 | int digit, largest_digit = 0; | |
7f2935c7 PB |
141 | int spec_long = 0; |
142 | ||
143 | op.unsignedp = 0; | |
144 | ||
f13eb63a ZW |
145 | if (p[0] == '0') |
146 | { | |
147 | if (end - start >= 3 && (p[1] == 'x' || p[1] == 'X')) | |
148 | { | |
149 | p += 2; | |
150 | base = 16; | |
151 | } | |
152 | else | |
153 | { | |
154 | p += 1; | |
155 | base = 8; | |
156 | } | |
7f2935c7 PB |
157 | } |
158 | ||
0f41302f | 159 | /* Some buggy compilers (e.g. MPW C) seem to need both casts. */ |
e915b770 KG |
160 | MAX_over_base = (((unsigned HOST_WIDEST_INT) -1) |
161 | / ((unsigned HOST_WIDEST_INT) base)); | |
7f2935c7 | 162 | |
f13eb63a ZW |
163 | while (p < end) |
164 | { | |
165 | c = *p++; | |
166 | ||
167 | if (c >= '0' && c <= '9') | |
168 | digit = c - '0'; | |
169 | else if (base == 16 && c >= 'a' && c <= 'f') /* FIXME: assumes ASCII */ | |
170 | digit = c - 'a' + 10; | |
171 | else if (base == 16 && c >= 'A' && c <= 'F') | |
172 | digit = c - 'A' + 10; | |
173 | else if (c == '.') | |
174 | { | |
175 | /* It's a float since it contains a point. */ | |
176 | cpp_error (pfile, | |
177 | "floating point numbers are not allowed in #if expressions"); | |
178 | goto error; | |
179 | } | |
180 | else | |
181 | { | |
182 | /* `l' means long, and `u' means unsigned. */ | |
183 | for (;;) | |
184 | { | |
185 | if (c == 'l' || c == 'L') | |
186 | spec_long++; | |
187 | else if (c == 'u' || c == 'U') | |
188 | op.unsignedp++; | |
189 | else | |
190 | { | |
191 | /* Decrement p here so that the error for an invalid number | |
192 | will be generated below in the case where this is the | |
193 | last character in the buffer. */ | |
194 | p--; | |
195 | break; | |
196 | } | |
197 | if (p == end) | |
198 | break; | |
199 | c = *p++; | |
200 | } | |
201 | /* Don't look for any more digits after the suffixes. */ | |
7f2935c7 | 202 | break; |
f13eb63a ZW |
203 | } |
204 | ||
205 | if (largest_digit < digit) | |
206 | largest_digit = digit; | |
207 | nd = n * base + digit; | |
208 | overflow |= MAX_over_base < n || nd < n; | |
209 | n = nd; | |
7f2935c7 | 210 | } |
7f2935c7 | 211 | |
f13eb63a | 212 | if (p != end) |
7f2935c7 | 213 | { |
f13eb63a ZW |
214 | cpp_error (pfile, "invalid number in #if expression"); |
215 | goto error; | |
7f2935c7 | 216 | } |
f13eb63a ZW |
217 | else if (spec_long > (CPP_OPTIONS (pfile)->c89 ? 1 : 2)) |
218 | { | |
219 | cpp_error (pfile, "too many `l' suffixes in integer constant"); | |
220 | goto error; | |
221 | } | |
222 | else if (op.unsignedp > 1) | |
223 | { | |
224 | cpp_error (pfile, "too many `u' suffixes in integer constant"); | |
225 | goto error; | |
226 | } | |
227 | ||
7f2935c7 | 228 | if (base <= largest_digit) |
7c4033ff | 229 | cpp_pedwarn (pfile, "integer constant contains digits beyond the radix"); |
7f2935c7 PB |
230 | |
231 | if (overflow) | |
7c4033ff | 232 | cpp_pedwarn (pfile, "integer constant out of range"); |
7f2935c7 PB |
233 | |
234 | /* If too big to be signed, consider it unsigned. */ | |
e915b770 | 235 | else if ((HOST_WIDEST_INT) n < 0 && ! op.unsignedp) |
7f2935c7 PB |
236 | { |
237 | if (base == 10) | |
f13eb63a ZW |
238 | cpp_warning (pfile, |
239 | "integer constant is so large that it is unsigned"); | |
7f2935c7 PB |
240 | op.unsignedp = 1; |
241 | } | |
242 | ||
243 | op.value = n; | |
244 | op.op = INT; | |
245 | return op; | |
f13eb63a ZW |
246 | |
247 | error: | |
248 | op.op = ERROR; | |
249 | return op; | |
7f2935c7 PB |
250 | } |
251 | ||
f13eb63a ZW |
252 | /* Parse and convert a character constant for #if. Understands backslash |
253 | escapes (\n, \031) and multibyte characters (if so configured). */ | |
254 | static struct operation | |
255 | parse_charconst (pfile, start, end) | |
256 | cpp_reader *pfile; | |
257 | U_CHAR *start; | |
258 | U_CHAR *end; | |
259 | { | |
260 | struct operation op; | |
e915b770 | 261 | HOST_WIDEST_INT result = 0; |
f13eb63a ZW |
262 | int num_chars = 0; |
263 | int num_bits; | |
264 | unsigned int width = MAX_CHAR_TYPE_SIZE, mask = MAX_CHAR_TYPE_MASK; | |
265 | int max_chars; | |
266 | U_CHAR *ptr = start; | |
267 | ||
099a9dd0 | 268 | int c = -1; |
f13eb63a ZW |
269 | |
270 | if (*ptr == 'L') | |
271 | { | |
272 | ++ptr; | |
273 | width = MAX_WCHAR_TYPE_SIZE, mask = MAX_WCHAR_TYPE_MASK; | |
274 | } | |
275 | max_chars = MAX_LONG_TYPE_SIZE / width; | |
276 | ||
277 | ++ptr; /* skip initial quote */ | |
278 | ||
279 | while (ptr < end) | |
280 | { | |
f13eb63a | 281 | c = *ptr++; |
f13eb63a ZW |
282 | if (c == '\'' || c == '\0') |
283 | break; | |
284 | else if (c == '\\') | |
285 | { | |
b0699dad | 286 | c = parse_escape (pfile, &ptr, mask); |
f13eb63a ZW |
287 | if (width < HOST_BITS_PER_INT |
288 | && (unsigned int) c >= (unsigned int)(1 << width)) | |
289 | cpp_pedwarn (pfile, "escape sequence out of range for character"); | |
290 | } | |
291 | ||
292 | /* Merge character into result; ignore excess chars. */ | |
293 | if (++num_chars <= max_chars) | |
294 | { | |
295 | if (width < HOST_BITS_PER_INT) | |
296 | result = (result << width) | (c & ((1 << width) - 1)); | |
297 | else | |
298 | result = c; | |
299 | } | |
300 | } | |
301 | ||
302 | if (num_chars == 0) | |
303 | { | |
304 | cpp_error (pfile, "empty character constant"); | |
305 | goto error; | |
306 | } | |
307 | else if (c != '\'') | |
308 | { | |
309 | /* cpp_get_token has already emitted an error if !traditional. */ | |
310 | if (! CPP_TRADITIONAL (pfile)) | |
311 | cpp_error (pfile, "malformatted character constant"); | |
312 | goto error; | |
313 | } | |
314 | else if (num_chars > max_chars) | |
315 | { | |
316 | cpp_error (pfile, "character constant too long"); | |
317 | goto error; | |
318 | } | |
319 | else if (num_chars != 1 && ! CPP_TRADITIONAL (pfile)) | |
320 | cpp_warning (pfile, "multi-character character constant"); | |
321 | ||
322 | /* If char type is signed, sign-extend the constant. */ | |
323 | num_bits = num_chars * width; | |
324 | ||
cf4ed945 ZW |
325 | if (cpp_defined (pfile, (const U_CHAR *)"__CHAR_UNSIGNED__", |
326 | sizeof ("__CHAR_UNSIGNED__")-1) | |
f13eb63a | 327 | || ((result >> (num_bits - 1)) & 1) == 0) |
ca261cb4 KG |
328 | op.value = result & ((unsigned HOST_WIDEST_INT) ~0 |
329 | >> (HOST_BITS_PER_WIDEST_INT - num_bits)); | |
f13eb63a | 330 | else |
ca261cb4 KG |
331 | op.value = result | ~((unsigned HOST_WIDEST_INT) ~0 |
332 | >> (HOST_BITS_PER_WIDEST_INT - num_bits)); | |
f13eb63a ZW |
333 | |
334 | /* This is always a signed type. */ | |
335 | op.unsignedp = 0; | |
336 | op.op = CHAR; | |
337 | return op; | |
338 | ||
339 | error: | |
340 | op.op = ERROR; | |
341 | return op; | |
342 | } | |
343 | ||
ba412f14 ZW |
344 | static struct operation |
345 | parse_defined (pfile) | |
346 | cpp_reader *pfile; | |
347 | { | |
348 | int paren = 0, len; | |
349 | U_CHAR *tok; | |
350 | enum cpp_token token; | |
351 | struct operation op; | |
352 | long old_written = CPP_WRITTEN (pfile); | |
353 | ||
354 | op.unsignedp = 0; | |
355 | op.op = INT; | |
356 | ||
357 | pfile->no_macro_expand++; | |
358 | token = get_directive_token (pfile); | |
359 | if (token == CPP_LPAREN) | |
360 | { | |
361 | paren++; | |
362 | CPP_SET_WRITTEN (pfile, old_written); | |
363 | token = get_directive_token (pfile); | |
364 | } | |
365 | ||
366 | if (token != CPP_NAME) | |
367 | goto oops; | |
368 | ||
369 | tok = pfile->token_buffer + old_written; | |
370 | len = CPP_PWRITTEN (pfile) - tok; | |
371 | op.value = cpp_defined (pfile, tok, len); | |
372 | ||
373 | if (paren) | |
374 | { | |
375 | if (get_directive_token (pfile) != CPP_RPAREN) | |
376 | goto oops; | |
377 | } | |
378 | CPP_SET_WRITTEN (pfile, old_written); | |
379 | pfile->no_macro_expand--; | |
380 | return op; | |
381 | ||
382 | oops: | |
383 | CPP_SET_WRITTEN (pfile, old_written); | |
384 | pfile->no_macro_expand--; | |
385 | cpp_error (pfile, "`defined' without an identifier"); | |
386 | ||
387 | op.op = ERROR; | |
388 | return op; | |
389 | } | |
390 | ||
f13eb63a | 391 | |
7f2935c7 | 392 | struct token { |
bcc5cac9 | 393 | const char *operator; |
7f2935c7 PB |
394 | int token; |
395 | }; | |
396 | ||
455d2586 | 397 | static const struct token tokentab2[] = { |
7f2935c7 PB |
398 | {"&&", ANDAND}, |
399 | {"||", OROR}, | |
400 | {"<<", LSH}, | |
401 | {">>", RSH}, | |
402 | {"==", EQUAL}, | |
403 | {"!=", NOTEQUAL}, | |
404 | {"<=", LEQ}, | |
405 | {">=", GEQ}, | |
406 | {"++", ERROR}, | |
407 | {"--", ERROR}, | |
408 | {NULL, ERROR} | |
409 | }; | |
410 | ||
0f41302f | 411 | /* Read one token. */ |
7f2935c7 | 412 | |
6de1e2a9 | 413 | static struct operation |
b0699dad | 414 | lex (pfile, skip_evaluation) |
52529158 | 415 | cpp_reader *pfile; |
c9666c01 | 416 | int skip_evaluation; |
7f2935c7 | 417 | { |
455d2586 | 418 | const struct token *toktab; |
7f2935c7 PB |
419 | enum cpp_token token; |
420 | struct operation op; | |
421 | U_CHAR *tok_start, *tok_end; | |
cf4ed945 | 422 | long old_written; |
7f2935c7 | 423 | |
1519594d | 424 | old_written = CPP_WRITTEN (pfile); |
cf4ed945 | 425 | token = get_directive_token (pfile); |
7f2935c7 | 426 | |
7f2935c7 PB |
427 | tok_start = pfile->token_buffer + old_written; |
428 | tok_end = CPP_PWRITTEN (pfile); | |
cf4ed945 | 429 | CPP_SET_WRITTEN (pfile, old_written); |
7f2935c7 | 430 | switch (token) |
ba412f14 | 431 | { |
0f41302f | 432 | case CPP_EOF: /* Should not happen ... */ |
a4a315ef | 433 | case CPP_VSPACE: |
7f2935c7 PB |
434 | op.op = 0; |
435 | return op; | |
7f2935c7 | 436 | case CPP_NUMBER: |
f13eb63a | 437 | return parse_number (pfile, tok_start, tok_end); |
7f2935c7 | 438 | case CPP_STRING: |
525bc95d | 439 | case CPP_WSTRING: |
cf4ed945 | 440 | cpp_error (pfile, "string constants are not allowed in #if expressions"); |
7f2935c7 PB |
441 | op.op = ERROR; |
442 | return op; | |
525bc95d | 443 | |
7f2935c7 | 444 | case CPP_CHAR: |
525bc95d | 445 | case CPP_WCHAR: |
f13eb63a | 446 | return parse_charconst (pfile, tok_start, tok_end); |
7f2935c7 PB |
447 | |
448 | case CPP_NAME: | |
ba412f14 ZW |
449 | if (!strcmp (tok_start, "defined")) |
450 | return parse_defined (pfile); | |
451 | ||
f13eb63a ZW |
452 | op.op = INT; |
453 | op.unsignedp = 0; | |
454 | op.value = 0; | |
5dfa4da1 | 455 | |
ba412f14 ZW |
456 | if (CPP_WARN_UNDEF (pfile) && !skip_evaluation) |
457 | cpp_warning (pfile, "`%.*s' is not defined", | |
458 | (int) (tok_end - tok_start), tok_start); | |
5dfa4da1 ZW |
459 | return op; |
460 | ||
ba412f14 ZW |
461 | case CPP_ASSERTION: |
462 | op.op = INT; | |
463 | op.unsignedp = 0; | |
464 | op.value = cpp_defined (pfile, tok_start, tok_end - tok_start); | |
f13eb63a | 465 | return op; |
7f2935c7 PB |
466 | |
467 | case CPP_OTHER: | |
468 | /* See if it is a special token of length 2. */ | |
469 | if (tok_start + 2 == tok_end) | |
470 | { | |
471 | for (toktab = tokentab2; toktab->operator != NULL; toktab++) | |
472 | if (tok_start[0] == toktab->operator[0] | |
473 | && tok_start[1] == toktab->operator[1]) | |
474 | break; | |
475 | if (toktab->token == ERROR) | |
ab87f8c8 JL |
476 | cpp_error (pfile, "`%s' not allowed in operand of `#if'", |
477 | tok_start); | |
7f2935c7 PB |
478 | op.op = toktab->token; |
479 | return op; | |
480 | } | |
481 | /* fall through */ | |
482 | default: | |
483 | op.op = *tok_start; | |
484 | return op; | |
485 | } | |
486 | } | |
487 | ||
488 | ||
489 | /* Parse a C escape sequence. STRING_PTR points to a variable | |
490 | containing a pointer to the string to parse. That pointer | |
491 | is updated past the characters we use. The value of the | |
492 | escape sequence is returned. | |
493 | ||
494 | A negative value means the sequence \ newline was seen, | |
495 | which is supposed to be equivalent to nothing at all. | |
496 | ||
497 | If \ is followed by a null character, we return a negative | |
498 | value and leave the string pointer pointing at the null character. | |
499 | ||
500 | If \ is followed by 000, we return 0 and leave the string pointer | |
501 | after the zeros. A value of 0 does not mean end of string. */ | |
502 | ||
a2c8e144 | 503 | static HOST_WIDEST_INT |
b0699dad | 504 | parse_escape (pfile, string_ptr, result_mask) |
7f2935c7 | 505 | cpp_reader *pfile; |
a2c8e144 | 506 | U_CHAR **string_ptr; |
e915b770 | 507 | HOST_WIDEST_INT result_mask; |
7f2935c7 PB |
508 | { |
509 | register int c = *(*string_ptr)++; | |
510 | switch (c) | |
511 | { | |
512 | case 'a': | |
513 | return TARGET_BELL; | |
514 | case 'b': | |
515 | return TARGET_BS; | |
516 | case 'e': | |
517 | case 'E': | |
f1a86df6 | 518 | if (CPP_OPTIONS (pfile)->pedantic) |
7f2935c7 | 519 | cpp_pedwarn (pfile, "non-ANSI-standard escape sequence, `\\%c'", c); |
f3ad1f9c | 520 | return TARGET_ESC; |
7f2935c7 PB |
521 | case 'f': |
522 | return TARGET_FF; | |
523 | case 'n': | |
524 | return TARGET_NEWLINE; | |
525 | case 'r': | |
526 | return TARGET_CR; | |
527 | case 't': | |
528 | return TARGET_TAB; | |
529 | case 'v': | |
530 | return TARGET_VT; | |
531 | case '\n': | |
532 | return -2; | |
533 | case 0: | |
534 | (*string_ptr)--; | |
535 | return 0; | |
536 | ||
537 | case '0': | |
538 | case '1': | |
539 | case '2': | |
540 | case '3': | |
541 | case '4': | |
542 | case '5': | |
543 | case '6': | |
544 | case '7': | |
545 | { | |
e915b770 | 546 | register HOST_WIDEST_INT i = c - '0'; |
7f2935c7 PB |
547 | register int count = 0; |
548 | while (++count < 3) | |
549 | { | |
550 | c = *(*string_ptr)++; | |
551 | if (c >= '0' && c <= '7') | |
552 | i = (i << 3) + c - '0'; | |
553 | else | |
554 | { | |
555 | (*string_ptr)--; | |
556 | break; | |
557 | } | |
558 | } | |
f1a86df6 | 559 | if (i != (i & result_mask)) |
7f2935c7 | 560 | { |
f1a86df6 ZW |
561 | i &= result_mask; |
562 | cpp_pedwarn (pfile, "octal escape sequence out of range"); | |
7f2935c7 PB |
563 | } |
564 | return i; | |
565 | } | |
566 | case 'x': | |
567 | { | |
e915b770 | 568 | register unsigned HOST_WIDEST_INT i = 0, overflow = 0; |
f1a86df6 | 569 | register int digits_found = 0, digit; |
7f2935c7 PB |
570 | for (;;) |
571 | { | |
572 | c = *(*string_ptr)++; | |
573 | if (c >= '0' && c <= '9') | |
574 | digit = c - '0'; | |
575 | else if (c >= 'a' && c <= 'f') | |
576 | digit = c - 'a' + 10; | |
577 | else if (c >= 'A' && c <= 'F') | |
578 | digit = c - 'A' + 10; | |
579 | else | |
580 | { | |
581 | (*string_ptr)--; | |
582 | break; | |
583 | } | |
584 | overflow |= i ^ (i << 4 >> 4); | |
585 | i = (i << 4) + digit; | |
586 | digits_found = 1; | |
587 | } | |
588 | if (!digits_found) | |
589 | cpp_error (pfile, "\\x used with no following hex digits"); | |
f1a86df6 | 590 | if (overflow | (i != (i & result_mask))) |
7f2935c7 | 591 | { |
f1a86df6 ZW |
592 | i &= result_mask; |
593 | cpp_pedwarn (pfile, "hex escape sequence out of range"); | |
7f2935c7 PB |
594 | } |
595 | return i; | |
596 | } | |
597 | default: | |
598 | return c; | |
599 | } | |
600 | } | |
601 | ||
602 | static void | |
603 | integer_overflow (pfile) | |
604 | cpp_reader *pfile; | |
605 | { | |
606 | if (CPP_PEDANTIC (pfile)) | |
607 | cpp_pedwarn (pfile, "integer overflow in preprocessor expression"); | |
608 | } | |
609 | ||
ca261cb4 | 610 | static HOST_WIDEST_INT |
7f2935c7 PB |
611 | left_shift (pfile, a, unsignedp, b) |
612 | cpp_reader *pfile; | |
ca261cb4 | 613 | HOST_WIDEST_INT a; |
e23c0ba3 | 614 | unsigned int unsignedp; |
ca261cb4 | 615 | unsigned HOST_WIDEST_INT b; |
7f2935c7 | 616 | { |
ca261cb4 | 617 | if (b >= HOST_BITS_PER_WIDEST_INT) |
7f2935c7 PB |
618 | { |
619 | if (! unsignedp && a != 0) | |
620 | integer_overflow (pfile); | |
621 | return 0; | |
622 | } | |
623 | else if (unsignedp) | |
ca261cb4 | 624 | return (unsigned HOST_WIDEST_INT) a << b; |
7f2935c7 PB |
625 | else |
626 | { | |
ca261cb4 | 627 | HOST_WIDEST_INT l = a << b; |
7f2935c7 PB |
628 | if (l >> b != a) |
629 | integer_overflow (pfile); | |
630 | return l; | |
631 | } | |
632 | } | |
633 | ||
ca261cb4 | 634 | static HOST_WIDEST_INT |
7f2935c7 | 635 | right_shift (pfile, a, unsignedp, b) |
d6f4ec51 | 636 | cpp_reader *pfile ATTRIBUTE_UNUSED; |
ca261cb4 | 637 | HOST_WIDEST_INT a; |
e23c0ba3 | 638 | unsigned int unsignedp; |
ca261cb4 | 639 | unsigned HOST_WIDEST_INT b; |
7f2935c7 | 640 | { |
ca261cb4 KG |
641 | if (b >= HOST_BITS_PER_WIDEST_INT) |
642 | return unsignedp ? 0 : a >> (HOST_BITS_PER_WIDEST_INT - 1); | |
7f2935c7 | 643 | else if (unsignedp) |
ca261cb4 | 644 | return (unsigned HOST_WIDEST_INT) a >> b; |
7f2935c7 PB |
645 | else |
646 | return a >> b; | |
647 | } | |
648 | \f | |
0f41302f | 649 | /* These priorities are all even, so we can handle associatively. */ |
7f2935c7 PB |
650 | #define PAREN_INNER_PRIO 0 |
651 | #define COMMA_PRIO 4 | |
652 | #define COND_PRIO (COMMA_PRIO+2) | |
653 | #define OROR_PRIO (COND_PRIO+2) | |
654 | #define ANDAND_PRIO (OROR_PRIO+2) | |
655 | #define OR_PRIO (ANDAND_PRIO+2) | |
656 | #define XOR_PRIO (OR_PRIO+2) | |
657 | #define AND_PRIO (XOR_PRIO+2) | |
658 | #define EQUAL_PRIO (AND_PRIO+2) | |
659 | #define LESS_PRIO (EQUAL_PRIO+2) | |
660 | #define SHIFT_PRIO (LESS_PRIO+2) | |
661 | #define PLUS_PRIO (SHIFT_PRIO+2) | |
662 | #define MUL_PRIO (PLUS_PRIO+2) | |
663 | #define UNARY_PRIO (MUL_PRIO+2) | |
664 | #define PAREN_OUTER_PRIO (UNARY_PRIO+2) | |
665 | ||
666 | #define COMPARE(OP) \ | |
667 | top->unsignedp = 0;\ | |
faa76596 | 668 | top->value = (unsigned1 || unsigned2) \ |
ca261cb4 | 669 | ? (unsigned HOST_WIDEST_INT) v1 OP (unsigned HOST_WIDEST_INT) v2 : (v1 OP v2) |
7f2935c7 PB |
670 | |
671 | /* Parse and evaluate a C expression, reading from PFILE. | |
672 | Returns the value of the expression. */ | |
673 | ||
e915b770 | 674 | HOST_WIDEST_INT |
b0699dad | 675 | _cpp_parse_expr (pfile) |
7f2935c7 PB |
676 | cpp_reader *pfile; |
677 | { | |
678 | /* The implementation is an operator precedence parser, | |
679 | i.e. a bottom-up parser, using a stack for not-yet-reduced tokens. | |
680 | ||
681 | The stack base is 'stack', and the current stack pointer is 'top'. | |
682 | There is a stack element for each operator (only), | |
683 | and the most recently pushed operator is 'top->op'. | |
684 | An operand (value) is stored in the 'value' field of the stack | |
685 | element of the operator that precedes it. | |
686 | In that case the 'flags' field has the HAVE_VALUE flag set. */ | |
687 | ||
688 | #define INIT_STACK_SIZE 20 | |
689 | struct operation init_stack[INIT_STACK_SIZE]; | |
690 | struct operation *stack = init_stack; | |
691 | struct operation *limit = stack + INIT_STACK_SIZE; | |
692 | register struct operation *top = stack; | |
e23c0ba3 | 693 | unsigned int lprio, rprio = 0; |
a4a315ef | 694 | int skip_evaluation = 0; |
7f2935c7 PB |
695 | |
696 | top->rprio = 0; | |
697 | top->flags = 0; | |
698 | for (;;) | |
699 | { | |
700 | struct operation op; | |
e23c0ba3 | 701 | U_CHAR flags = 0; |
7f2935c7 PB |
702 | |
703 | /* Read a token */ | |
b0699dad | 704 | op = lex (pfile, skip_evaluation); |
7f2935c7 PB |
705 | |
706 | /* See if the token is an operand, in which case go to set_value. | |
707 | If the token is an operator, figure out its left and right | |
0f41302f | 708 | priorities, and then goto maybe_reduce. */ |
7f2935c7 PB |
709 | |
710 | switch (op.op) | |
711 | { | |
712 | case NAME: | |
b0699dad | 713 | cpp_ice (pfile, "lex returns a NAME"); |
34ca9541 | 714 | goto syntax_error; |
7f2935c7 | 715 | case INT: case CHAR: |
7f2935c7 PB |
716 | goto set_value; |
717 | case 0: | |
718 | lprio = 0; goto maybe_reduce; | |
719 | case '+': case '-': | |
cf4ed945 ZW |
720 | if (top->flags & HAVE_VALUE) |
721 | { | |
722 | lprio = PLUS_PRIO; | |
723 | goto binop; | |
724 | } | |
725 | /* else fall through */ | |
7f2935c7 PB |
726 | case '!': case '~': |
727 | flags = RIGHT_OPERAND_REQUIRED; | |
728 | rprio = UNARY_PRIO; lprio = rprio + 1; goto maybe_reduce; | |
729 | case '*': case '/': case '%': | |
730 | lprio = MUL_PRIO; goto binop; | |
731 | case '<': case '>': case LEQ: case GEQ: | |
732 | lprio = LESS_PRIO; goto binop; | |
733 | case EQUAL: case NOTEQUAL: | |
734 | lprio = EQUAL_PRIO; goto binop; | |
735 | case LSH: case RSH: | |
736 | lprio = SHIFT_PRIO; goto binop; | |
737 | case '&': lprio = AND_PRIO; goto binop; | |
738 | case '^': lprio = XOR_PRIO; goto binop; | |
739 | case '|': lprio = OR_PRIO; goto binop; | |
740 | case ANDAND: lprio = ANDAND_PRIO; goto binop; | |
741 | case OROR: lprio = OROR_PRIO; goto binop; | |
742 | case ',': | |
743 | lprio = COMMA_PRIO; goto binop; | |
744 | case '(': | |
745 | lprio = PAREN_OUTER_PRIO; rprio = PAREN_INNER_PRIO; | |
746 | goto maybe_reduce; | |
747 | case ')': | |
748 | lprio = PAREN_INNER_PRIO; rprio = PAREN_OUTER_PRIO; | |
749 | goto maybe_reduce; | |
750 | case ':': | |
751 | lprio = COND_PRIO; rprio = COND_PRIO; | |
752 | goto maybe_reduce; | |
753 | case '?': | |
754 | lprio = COND_PRIO + 1; rprio = COND_PRIO; | |
755 | goto maybe_reduce; | |
f13eb63a ZW |
756 | case ERROR: |
757 | goto syntax_error; | |
7f2935c7 PB |
758 | default: |
759 | cpp_error (pfile, "invalid character in #if"); | |
760 | goto syntax_error; | |
761 | } | |
762 | ||
763 | set_value: | |
0f41302f | 764 | /* Push a value onto the stack. */ |
7f2935c7 PB |
765 | if (top->flags & HAVE_VALUE) |
766 | { | |
767 | cpp_error (pfile, "syntax error in #if"); | |
768 | goto syntax_error; | |
769 | } | |
cf4ed945 ZW |
770 | top->value = op.value; |
771 | top->unsignedp = op.unsignedp; | |
7f2935c7 PB |
772 | top->flags |= HAVE_VALUE; |
773 | continue; | |
774 | ||
cf4ed945 ZW |
775 | binop: |
776 | flags = LEFT_OPERAND_REQUIRED|RIGHT_OPERAND_REQUIRED; | |
777 | rprio = lprio + 1; | |
778 | ||
7f2935c7 | 779 | maybe_reduce: |
0f41302f | 780 | /* Push an operator, and check if we can reduce now. */ |
7f2935c7 PB |
781 | while (top->rprio > lprio) |
782 | { | |
ca261cb4 | 783 | HOST_WIDEST_INT v1 = top[-1].value, v2 = top[0].value; |
e23c0ba3 ZW |
784 | unsigned int unsigned1 = top[-1].unsignedp; |
785 | unsigned int unsigned2 = top[0].unsignedp; | |
7f2935c7 PB |
786 | top--; |
787 | if ((top[1].flags & LEFT_OPERAND_REQUIRED) | |
788 | && ! (top[0].flags & HAVE_VALUE)) | |
789 | { | |
790 | cpp_error (pfile, "syntax error - missing left operand"); | |
791 | goto syntax_error; | |
792 | } | |
793 | if ((top[1].flags & RIGHT_OPERAND_REQUIRED) | |
794 | && ! (top[1].flags & HAVE_VALUE)) | |
795 | { | |
796 | cpp_error (pfile, "syntax error - missing right operand"); | |
797 | goto syntax_error; | |
798 | } | |
799 | /* top[0].value = (top[1].op)(v1, v2);*/ | |
800 | switch (top[1].op) | |
801 | { | |
802 | case '+': | |
803 | if (!(top->flags & HAVE_VALUE)) | |
804 | { /* Unary '+' */ | |
805 | top->value = v2; | |
806 | top->unsignedp = unsigned2; | |
807 | top->flags |= HAVE_VALUE; | |
808 | } | |
809 | else | |
810 | { | |
811 | top->value = v1 + v2; | |
812 | top->unsignedp = unsigned1 || unsigned2; | |
a4a315ef | 813 | if (! top->unsignedp && ! skip_evaluation |
7f2935c7 PB |
814 | && ! possible_sum_sign (v1, v2, top->value)) |
815 | integer_overflow (pfile); | |
816 | } | |
817 | break; | |
818 | case '-': | |
52529158 | 819 | if (!(top->flags & HAVE_VALUE)) |
7f2935c7 PB |
820 | { /* Unary '-' */ |
821 | top->value = - v2; | |
52529158 | 822 | if (!skip_evaluation && (top->value & v2) < 0 && !unsigned2) |
7f2935c7 PB |
823 | integer_overflow (pfile); |
824 | top->unsignedp = unsigned2; | |
825 | top->flags |= HAVE_VALUE; | |
826 | } | |
827 | else | |
828 | { /* Binary '-' */ | |
829 | top->value = v1 - v2; | |
830 | top->unsignedp = unsigned1 || unsigned2; | |
52529158 | 831 | if (! top->unsignedp && ! skip_evaluation |
7f2935c7 PB |
832 | && ! possible_sum_sign (top->value, v2, v1)) |
833 | integer_overflow (pfile); | |
834 | } | |
835 | break; | |
836 | case '*': | |
837 | top->unsignedp = unsigned1 || unsigned2; | |
838 | if (top->unsignedp) | |
ca261cb4 | 839 | top->value = (unsigned HOST_WIDEST_INT) v1 * v2; |
a4a315ef | 840 | else if (!skip_evaluation) |
7f2935c7 PB |
841 | { |
842 | top->value = v1 * v2; | |
843 | if (v1 | |
844 | && (top->value / v1 != v2 | |
845 | || (top->value & v1 & v2) < 0)) | |
846 | integer_overflow (pfile); | |
847 | } | |
848 | break; | |
849 | case '/': | |
a4a315ef PB |
850 | if (skip_evaluation) |
851 | break; | |
7f2935c7 PB |
852 | if (v2 == 0) |
853 | { | |
854 | cpp_error (pfile, "division by zero in #if"); | |
855 | v2 = 1; | |
856 | } | |
857 | top->unsignedp = unsigned1 || unsigned2; | |
858 | if (top->unsignedp) | |
ca261cb4 | 859 | top->value = (unsigned HOST_WIDEST_INT) v1 / v2; |
7f2935c7 PB |
860 | else |
861 | { | |
862 | top->value = v1 / v2; | |
863 | if ((top->value & v1 & v2) < 0) | |
864 | integer_overflow (pfile); | |
865 | } | |
866 | break; | |
867 | case '%': | |
a4a315ef PB |
868 | if (skip_evaluation) |
869 | break; | |
7f2935c7 PB |
870 | if (v2 == 0) |
871 | { | |
872 | cpp_error (pfile, "division by zero in #if"); | |
873 | v2 = 1; | |
874 | } | |
875 | top->unsignedp = unsigned1 || unsigned2; | |
876 | if (top->unsignedp) | |
ca261cb4 | 877 | top->value = (unsigned HOST_WIDEST_INT) v1 % v2; |
7f2935c7 PB |
878 | else |
879 | top->value = v1 % v2; | |
880 | break; | |
881 | case '!': | |
882 | if (top->flags & HAVE_VALUE) | |
883 | { | |
884 | cpp_error (pfile, "syntax error"); | |
885 | goto syntax_error; | |
886 | } | |
887 | top->value = ! v2; | |
888 | top->unsignedp = 0; | |
889 | top->flags |= HAVE_VALUE; | |
890 | break; | |
891 | case '~': | |
892 | if (top->flags & HAVE_VALUE) | |
893 | { | |
894 | cpp_error (pfile, "syntax error"); | |
895 | goto syntax_error; | |
896 | } | |
897 | top->value = ~ v2; | |
898 | top->unsignedp = unsigned2; | |
899 | top->flags |= HAVE_VALUE; | |
900 | break; | |
901 | case '<': COMPARE(<); break; | |
902 | case '>': COMPARE(>); break; | |
903 | case LEQ: COMPARE(<=); break; | |
904 | case GEQ: COMPARE(>=); break; | |
905 | case EQUAL: | |
906 | top->value = (v1 == v2); | |
907 | top->unsignedp = 0; | |
908 | break; | |
909 | case NOTEQUAL: | |
910 | top->value = (v1 != v2); | |
911 | top->unsignedp = 0; | |
912 | break; | |
913 | case LSH: | |
a4a315ef PB |
914 | if (skip_evaluation) |
915 | break; | |
7f2935c7 PB |
916 | top->unsignedp = unsigned1; |
917 | if (v2 < 0 && ! unsigned2) | |
918 | top->value = right_shift (pfile, v1, unsigned1, -v2); | |
919 | else | |
920 | top->value = left_shift (pfile, v1, unsigned1, v2); | |
921 | break; | |
922 | case RSH: | |
a4a315ef PB |
923 | if (skip_evaluation) |
924 | break; | |
7f2935c7 PB |
925 | top->unsignedp = unsigned1; |
926 | if (v2 < 0 && ! unsigned2) | |
927 | top->value = left_shift (pfile, v1, unsigned1, -v2); | |
928 | else | |
929 | top->value = right_shift (pfile, v1, unsigned1, v2); | |
930 | break; | |
931 | #define LOGICAL(OP) \ | |
932 | top->value = v1 OP v2;\ | |
933 | top->unsignedp = unsigned1 || unsigned2; | |
934 | case '&': LOGICAL(&); break; | |
935 | case '^': LOGICAL(^); break; | |
936 | case '|': LOGICAL(|); break; | |
937 | case ANDAND: | |
a4a315ef PB |
938 | top->value = v1 && v2; top->unsignedp = 0; |
939 | if (!v1) skip_evaluation--; | |
940 | break; | |
7f2935c7 | 941 | case OROR: |
a4a315ef PB |
942 | top->value = v1 || v2; top->unsignedp = 0; |
943 | if (v1) skip_evaluation--; | |
944 | break; | |
7f2935c7 PB |
945 | case ',': |
946 | if (CPP_PEDANTIC (pfile)) | |
947 | cpp_pedwarn (pfile, "comma operator in operand of `#if'"); | |
948 | top->value = v2; | |
949 | top->unsignedp = unsigned2; | |
950 | break; | |
951 | case '(': case '?': | |
952 | cpp_error (pfile, "syntax error in #if"); | |
953 | goto syntax_error; | |
954 | case ':': | |
955 | if (top[0].op != '?') | |
956 | { | |
957 | cpp_error (pfile, | |
958 | "syntax error ':' without preceding '?'"); | |
959 | goto syntax_error; | |
960 | } | |
961 | else if (! (top[1].flags & HAVE_VALUE) | |
962 | || !(top[-1].flags & HAVE_VALUE) | |
963 | || !(top[0].flags & HAVE_VALUE)) | |
964 | { | |
965 | cpp_error (pfile, "bad syntax for ?: operator"); | |
966 | goto syntax_error; | |
967 | } | |
968 | else | |
969 | { | |
970 | top--; | |
a4a315ef | 971 | if (top->value) skip_evaluation--; |
7f2935c7 PB |
972 | top->value = top->value ? v1 : v2; |
973 | top->unsignedp = unsigned1 || unsigned2; | |
974 | } | |
975 | break; | |
976 | case ')': | |
977 | if ((top[1].flags & HAVE_VALUE) | |
978 | || ! (top[0].flags & HAVE_VALUE) | |
979 | || top[0].op != '(' | |
980 | || (top[-1].flags & HAVE_VALUE)) | |
981 | { | |
982 | cpp_error (pfile, "mismatched parentheses in #if"); | |
983 | goto syntax_error; | |
984 | } | |
985 | else | |
986 | { | |
987 | top--; | |
988 | top->value = v1; | |
989 | top->unsignedp = unsigned1; | |
990 | top->flags |= HAVE_VALUE; | |
991 | } | |
992 | break; | |
993 | default: | |
a9ae4483 ZW |
994 | if (ISGRAPH (top[1].op)) |
995 | cpp_error (pfile, "unimplemented operator '%c'\n", top[1].op); | |
996 | else | |
997 | cpp_error (pfile, "unimplemented operator '\\%03o'\n", | |
998 | top[1].op); | |
7f2935c7 PB |
999 | } |
1000 | } | |
1001 | if (op.op == 0) | |
1002 | { | |
1003 | if (top != stack) | |
c1212d2f | 1004 | cpp_ice (pfile, "unbalanced stack in #if expression"); |
7f2935c7 PB |
1005 | if (stack != init_stack) |
1006 | free (stack); | |
1007 | return top->value; | |
1008 | } | |
1009 | top++; | |
1010 | ||
0f41302f | 1011 | /* Check for and handle stack overflow. */ |
7f2935c7 PB |
1012 | if (top == limit) |
1013 | { | |
1014 | struct operation *new_stack; | |
0f41302f | 1015 | int old_size = (char *) limit - (char *) stack; |
7f2935c7 PB |
1016 | int new_size = 2 * old_size; |
1017 | if (stack != init_stack) | |
0f41302f | 1018 | new_stack = (struct operation *) xrealloc (stack, new_size); |
7f2935c7 PB |
1019 | else |
1020 | { | |
0f41302f | 1021 | new_stack = (struct operation *) xmalloc (new_size); |
b0699dad | 1022 | memcpy (new_stack, stack, old_size); |
7f2935c7 PB |
1023 | } |
1024 | stack = new_stack; | |
0f41302f MS |
1025 | top = (struct operation *) ((char *) new_stack + old_size); |
1026 | limit = (struct operation *) ((char *) new_stack + new_size); | |
7f2935c7 PB |
1027 | } |
1028 | ||
1029 | top->flags = flags; | |
1030 | top->rprio = rprio; | |
1031 | top->op = op.op; | |
a4a315ef PB |
1032 | if ((op.op == OROR && top[-1].value) |
1033 | || (op.op == ANDAND && !top[-1].value) | |
1034 | || (op.op == '?' && !top[-1].value)) | |
1035 | { | |
1036 | skip_evaluation++; | |
1037 | } | |
1038 | else if (op.op == ':') | |
1039 | { | |
1040 | if (top[-2].value) /* Was condition true? */ | |
1041 | skip_evaluation++; | |
1042 | else | |
1043 | skip_evaluation--; | |
1044 | } | |
7f2935c7 PB |
1045 | } |
1046 | syntax_error: | |
1047 | if (stack != init_stack) | |
1048 | free (stack); | |
7f2935c7 PB |
1049 | return 0; |
1050 | } |