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b0699dad | 1 | /* Parse C expressions for cpplib. |
5d8ebbd8 NB |
2 | Copyright (C) 1987, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2001, |
3 | 2002 Free Software Foundation. | |
e38992e8 | 4 | Contributed by Per Bothner, 1994. |
7f2935c7 PB |
5 | |
6 | This program is free software; you can redistribute it and/or modify it | |
7 | under the terms of the GNU General Public License as published by the | |
8 | Free Software Foundation; either version 2, or (at your option) any | |
9 | later version. | |
10 | ||
11 | This program is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with this program; if not, write to the Free Software | |
940d9d63 | 18 | Foundation, 59 Temple Place - Suite 330, |
e38992e8 | 19 | Boston, MA 02111-1307, USA. */ |
7f2935c7 | 20 | |
7f2935c7 | 21 | #include "config.h" |
b04cd507 | 22 | #include "system.h" |
487a6e06 | 23 | #include "cpplib.h" |
88ae23e7 | 24 | #include "cpphash.h" |
7f2935c7 | 25 | |
91318908 NB |
26 | #define PART_PRECISION (sizeof (cpp_num_part) * CHAR_BIT) |
27 | #define HALF_MASK (~(cpp_num_part) 0 >> (PART_PRECISION / 2)) | |
28 | #define LOW_PART(num_part) (num_part & HALF_MASK) | |
29 | #define HIGH_PART(num_part) (num_part >> (PART_PRECISION / 2)) | |
30 | ||
cf00a885 | 31 | struct op |
b0699dad | 32 | { |
68e65275 | 33 | const cpp_token *token; /* The token forming op (for diagnostics). */ |
ad28cff7 | 34 | cpp_num value; /* The value logically "right" of op. */ |
cf00a885 | 35 | enum cpp_ttype op; |
7f2935c7 | 36 | }; |
7f2935c7 | 37 | |
91318908 NB |
38 | /* Some simple utility routines on double integers. */ |
39 | #define num_zerop(num) ((num.low | num.high) == 0) | |
40 | #define num_eq(num1, num2) (num1.low == num2.low && num1.high == num2.high) | |
41 | static bool num_positive PARAMS ((cpp_num, size_t)); | |
42 | static bool num_greater_eq PARAMS ((cpp_num, cpp_num, size_t)); | |
43 | static cpp_num num_trim PARAMS ((cpp_num, size_t)); | |
44 | static cpp_num num_part_mul PARAMS ((cpp_num_part, cpp_num_part)); | |
45 | ||
46 | static cpp_num num_unary_op PARAMS ((cpp_reader *, cpp_num, enum cpp_ttype)); | |
47 | static cpp_num num_binary_op PARAMS ((cpp_reader *, cpp_num, cpp_num, | |
48 | enum cpp_ttype)); | |
49 | static cpp_num num_negate PARAMS ((cpp_num, size_t)); | |
50 | static cpp_num num_bitwise_op PARAMS ((cpp_reader *, cpp_num, cpp_num, | |
51 | enum cpp_ttype)); | |
52 | static cpp_num num_inequality_op PARAMS ((cpp_reader *, cpp_num, cpp_num, | |
53 | enum cpp_ttype)); | |
54 | static cpp_num num_equality_op PARAMS ((cpp_reader *, cpp_num, cpp_num, | |
55 | enum cpp_ttype)); | |
ad28cff7 | 56 | static cpp_num num_mul PARAMS ((cpp_reader *, cpp_num, cpp_num)); |
91318908 NB |
57 | static cpp_num num_div_op PARAMS ((cpp_reader *, cpp_num, cpp_num, |
58 | enum cpp_ttype)); | |
59 | static cpp_num num_lshift PARAMS ((cpp_num, size_t, size_t)); | |
60 | static cpp_num num_rshift PARAMS ((cpp_num, size_t, size_t)); | |
61 | ||
62 | static cpp_num append_digit PARAMS ((cpp_num, int, int, size_t)); | |
91318908 NB |
63 | static cpp_num parse_defined PARAMS ((cpp_reader *)); |
64 | static cpp_num eval_token PARAMS ((cpp_reader *, const cpp_token *)); | |
65 | static struct op *reduce PARAMS ((cpp_reader *, struct op *, enum cpp_ttype)); | |
cd7ab83f NB |
66 | static unsigned int interpret_float_suffix PARAMS ((const uchar *, size_t)); |
67 | static unsigned int interpret_int_suffix PARAMS ((const uchar *, size_t)); | |
68e65275 | 68 | static void check_promotion PARAMS ((cpp_reader *, const struct op *)); |
91318908 | 69 | |
cd7ab83f | 70 | /* Token type abuse to create unary plus and minus operators. */ |
f8b954fc NB |
71 | #define CPP_UPLUS (CPP_LAST_CPP_OP + 1) |
72 | #define CPP_UMINUS (CPP_LAST_CPP_OP + 2) | |
cf00a885 | 73 | |
15dad1d9 ZW |
74 | /* With -O2, gcc appears to produce nice code, moving the error |
75 | message load and subsequent jump completely out of the main path. */ | |
15dad1d9 | 76 | #define SYNTAX_ERROR(msgid) \ |
ebef4e8c | 77 | do { cpp_error (pfile, DL_ERROR, msgid); goto syntax_error; } while(0) |
15dad1d9 | 78 | #define SYNTAX_ERROR2(msgid, arg) \ |
ebef4e8c | 79 | do { cpp_error (pfile, DL_ERROR, msgid, arg); goto syntax_error; } while(0) |
15dad1d9 | 80 | |
cd7ab83f NB |
81 | /* Subroutine of cpp_classify_number. S points to a float suffix of |
82 | length LEN, possibly zero. Returns 0 for an invalid suffix, or a | |
83 | flag vector describing the suffix. */ | |
84 | static unsigned int | |
85 | interpret_float_suffix (s, len) | |
86 | const uchar *s; | |
87 | size_t len; | |
cf00a885 | 88 | { |
cd7ab83f | 89 | size_t f = 0, l = 0, i = 0; |
cf00a885 | 90 | |
cd7ab83f NB |
91 | while (len--) |
92 | switch (s[len]) | |
93 | { | |
94 | case 'f': case 'F': f++; break; | |
95 | case 'l': case 'L': l++; break; | |
96 | case 'i': case 'I': | |
97 | case 'j': case 'J': i++; break; | |
98 | default: | |
99 | return 0; | |
100 | } | |
cf00a885 | 101 | |
cd7ab83f NB |
102 | if (f + l > 1 || i > 1) |
103 | return 0; | |
7f2935c7 | 104 | |
cd7ab83f NB |
105 | return ((i ? CPP_N_IMAGINARY : 0) |
106 | | (f ? CPP_N_SMALL : | |
107 | l ? CPP_N_LARGE : CPP_N_MEDIUM)); | |
108 | } | |
109 | ||
110 | /* Subroutine of cpp_classify_number. S points to an integer suffix | |
111 | of length LEN, possibly zero. Returns 0 for an invalid suffix, or a | |
112 | flag vector describing the suffix. */ | |
113 | static unsigned int | |
114 | interpret_int_suffix (s, len) | |
115 | const uchar *s; | |
116 | size_t len; | |
117 | { | |
118 | size_t u, l, i; | |
119 | ||
120 | u = l = i = 0; | |
121 | ||
122 | while (len--) | |
123 | switch (s[len]) | |
124 | { | |
125 | case 'u': case 'U': u++; break; | |
126 | case 'i': case 'I': | |
127 | case 'j': case 'J': i++; break; | |
128 | case 'l': case 'L': l++; | |
129 | /* If there are two Ls, they must be adjacent and the same case. */ | |
130 | if (l == 2 && s[len] != s[len + 1]) | |
131 | return 0; | |
132 | break; | |
133 | default: | |
134 | return 0; | |
135 | } | |
136 | ||
137 | if (l > 2 || u > 1 || i > 1) | |
138 | return 0; | |
139 | ||
140 | return ((i ? CPP_N_IMAGINARY : 0) | |
141 | | (u ? CPP_N_UNSIGNED : 0) | |
142 | | ((l == 0) ? CPP_N_SMALL | |
143 | : (l == 1) ? CPP_N_MEDIUM : CPP_N_LARGE)); | |
144 | } | |
145 | ||
146 | /* Categorize numeric constants according to their field (integer, | |
147 | floating point, or invalid), radix (decimal, octal, hexadecimal), | |
148 | and type suffixes. */ | |
149 | unsigned int | |
150 | cpp_classify_number (pfile, token) | |
151 | cpp_reader *pfile; | |
152 | const cpp_token *token; | |
153 | { | |
154 | const uchar *str = token->val.str.text; | |
155 | const uchar *limit; | |
156 | unsigned int max_digit, result, radix; | |
157 | enum {NOT_FLOAT = 0, AFTER_POINT, AFTER_EXPON} float_flag; | |
158 | ||
159 | /* If the lexer has done its job, length one can only be a single | |
160 | digit. Fast-path this very common case. */ | |
161 | if (token->val.str.len == 1) | |
162 | return CPP_N_INTEGER | CPP_N_SMALL | CPP_N_DECIMAL; | |
163 | ||
164 | limit = str + token->val.str.len; | |
165 | float_flag = NOT_FLOAT; | |
166 | max_digit = 0; | |
167 | radix = 10; | |
168 | ||
169 | /* First, interpret the radix. */ | |
170 | if (*str == '0') | |
171 | { | |
172 | radix = 8; | |
173 | str++; | |
174 | ||
175 | /* Require at least one hex digit to classify it as hex. */ | |
176 | if ((*str == 'x' || *str == 'X') && ISXDIGIT (str[1])) | |
177 | { | |
178 | radix = 16; | |
179 | str++; | |
180 | } | |
181 | } | |
182 | ||
183 | /* Now scan for a well-formed integer or float. */ | |
184 | for (;;) | |
185 | { | |
186 | unsigned int c = *str++; | |
187 | ||
188 | if (ISDIGIT (c) || (ISXDIGIT (c) && radix == 16)) | |
189 | { | |
190 | c = hex_value (c); | |
191 | if (c > max_digit) | |
192 | max_digit = c; | |
193 | } | |
194 | else if (c == '.') | |
195 | { | |
196 | if (float_flag == NOT_FLOAT) | |
197 | float_flag = AFTER_POINT; | |
198 | else | |
199 | SYNTAX_ERROR ("too many decimal points in number"); | |
200 | } | |
201 | else if ((radix <= 10 && (c == 'e' || c == 'E')) | |
202 | || (radix == 16 && (c == 'p' || c == 'P'))) | |
203 | { | |
204 | float_flag = AFTER_EXPON; | |
205 | break; | |
206 | } | |
207 | else | |
208 | { | |
209 | /* Start of suffix. */ | |
210 | str--; | |
211 | break; | |
212 | } | |
213 | } | |
214 | ||
215 | if (float_flag != NOT_FLOAT && radix == 8) | |
216 | radix = 10; | |
217 | ||
218 | if (max_digit >= radix) | |
219 | SYNTAX_ERROR2 ("invalid digit \"%c\" in octal constant", '0' + max_digit); | |
220 | ||
221 | if (float_flag != NOT_FLOAT) | |
222 | { | |
223 | if (radix == 16 && CPP_PEDANTIC (pfile) && !CPP_OPTION (pfile, c99)) | |
224 | cpp_error (pfile, DL_PEDWARN, | |
225 | "use of C99 hexadecimal floating constant"); | |
226 | ||
227 | if (float_flag == AFTER_EXPON) | |
228 | { | |
229 | if (*str == '+' || *str == '-') | |
230 | str++; | |
231 | ||
232 | /* Exponent is decimal, even if string is a hex float. */ | |
233 | if (!ISDIGIT (*str)) | |
234 | SYNTAX_ERROR ("exponent has no digits"); | |
235 | ||
236 | do | |
237 | str++; | |
238 | while (ISDIGIT (*str)); | |
239 | } | |
240 | else if (radix == 16) | |
241 | SYNTAX_ERROR ("hexadecimal floating constants require an exponent"); | |
242 | ||
243 | result = interpret_float_suffix (str, limit - str); | |
244 | if (result == 0) | |
245 | { | |
246 | cpp_error (pfile, DL_ERROR, | |
247 | "invalid suffix \"%.*s\" on floating constant", | |
91b12472 | 248 | (int) (limit - str), str); |
cd7ab83f NB |
249 | return CPP_N_INVALID; |
250 | } | |
251 | ||
252 | /* Traditional C didn't accept any floating suffixes. */ | |
253 | if (limit != str | |
254 | && CPP_WTRADITIONAL (pfile) | |
255 | && ! cpp_sys_macro_p (pfile)) | |
256 | cpp_error (pfile, DL_WARNING, | |
257 | "traditional C rejects the \"%.*s\" suffix", | |
91b12472 | 258 | (int) (limit - str), str); |
cd7ab83f NB |
259 | |
260 | result |= CPP_N_FLOATING; | |
261 | } | |
262 | else | |
263 | { | |
264 | result = interpret_int_suffix (str, limit - str); | |
265 | if (result == 0) | |
266 | { | |
267 | cpp_error (pfile, DL_ERROR, | |
268 | "invalid suffix \"%.*s\" on integer constant", | |
91b12472 | 269 | (int) (limit - str), str); |
cd7ab83f NB |
270 | return CPP_N_INVALID; |
271 | } | |
272 | ||
56da7207 ZW |
273 | /* Traditional C only accepted the 'L' suffix. |
274 | Suppress warning about 'LL' with -Wno-long-long. */ | |
275 | if (CPP_WTRADITIONAL (pfile) && ! cpp_sys_macro_p (pfile)) | |
276 | { | |
277 | int u_or_i = (result & (CPP_N_UNSIGNED|CPP_N_IMAGINARY)); | |
278 | int large = (result & CPP_N_WIDTH) == CPP_N_LARGE; | |
279 | ||
280 | if (u_or_i || (large && CPP_OPTION (pfile, warn_long_long))) | |
281 | cpp_error (pfile, DL_WARNING, | |
282 | "traditional C rejects the \"%.*s\" suffix", | |
283 | (int) (limit - str), str); | |
284 | } | |
cd7ab83f NB |
285 | |
286 | if ((result & CPP_N_WIDTH) == CPP_N_LARGE | |
287 | && ! CPP_OPTION (pfile, c99) | |
288 | && CPP_OPTION (pfile, warn_long_long)) | |
289 | cpp_error (pfile, DL_PEDWARN, "use of C99 long long integer constant"); | |
290 | ||
291 | result |= CPP_N_INTEGER; | |
292 | } | |
293 | ||
294 | if ((result & CPP_N_IMAGINARY) && CPP_PEDANTIC (pfile)) | |
295 | cpp_error (pfile, DL_PEDWARN, "imaginary constants are a GCC extension"); | |
296 | ||
297 | if (radix == 10) | |
298 | result |= CPP_N_DECIMAL; | |
299 | else if (radix == 16) | |
300 | result |= CPP_N_HEX; | |
301 | else | |
302 | result |= CPP_N_OCTAL; | |
303 | ||
304 | return result; | |
305 | ||
306 | syntax_error: | |
307 | return CPP_N_INVALID; | |
308 | } | |
309 | ||
310 | /* cpp_interpret_integer converts an integer constant into a cpp_num, | |
311 | of precision options->precision. | |
312 | ||
313 | We do not provide any interface for decimal->float conversion, | |
314 | because the preprocessor doesn't need it and the floating point | |
315 | handling in GCC proper is too ugly to speak of. */ | |
316 | cpp_num | |
317 | cpp_interpret_integer (pfile, token, type) | |
318 | cpp_reader *pfile; | |
319 | const cpp_token *token; | |
320 | unsigned int type; | |
321 | { | |
322 | const uchar *p, *end; | |
323 | cpp_num result; | |
324 | ||
325 | result.low = 0; | |
326 | result.high = 0; | |
23ff0223 NB |
327 | result.unsignedp = !!(type & CPP_N_UNSIGNED); |
328 | result.overflow = false; | |
cd7ab83f NB |
329 | |
330 | p = token->val.str.text; | |
331 | end = p + token->val.str.len; | |
332 | ||
333 | /* Common case of a single digit. */ | |
334 | if (token->val.str.len == 1) | |
335 | result.low = p[0] - '0'; | |
336 | else | |
337 | { | |
338 | cpp_num_part max; | |
339 | size_t precision = CPP_OPTION (pfile, precision); | |
340 | unsigned int base = 10, c = 0; | |
341 | bool overflow = false; | |
342 | ||
343 | if ((type & CPP_N_RADIX) == CPP_N_OCTAL) | |
344 | { | |
345 | base = 8; | |
346 | p++; | |
347 | } | |
348 | else if ((type & CPP_N_RADIX) == CPP_N_HEX) | |
349 | { | |
350 | base = 16; | |
351 | p += 2; | |
352 | } | |
353 | ||
354 | /* We can add a digit to numbers strictly less than this without | |
355 | needing the precision and slowness of double integers. */ | |
356 | max = ~(cpp_num_part) 0; | |
357 | if (precision < PART_PRECISION) | |
358 | max >>= PART_PRECISION - precision; | |
359 | max = (max - base + 1) / base + 1; | |
360 | ||
361 | for (; p < end; p++) | |
362 | { | |
363 | c = *p; | |
364 | ||
365 | if (ISDIGIT (c) || (base == 16 && ISXDIGIT (c))) | |
366 | c = hex_value (c); | |
367 | else | |
368 | break; | |
369 | ||
370 | /* Strict inequality for when max is set to zero. */ | |
371 | if (result.low < max) | |
372 | result.low = result.low * base + c; | |
373 | else | |
374 | { | |
375 | result = append_digit (result, c, base, precision); | |
376 | overflow |= result.overflow; | |
377 | max = 0; | |
378 | } | |
379 | } | |
380 | ||
381 | if (overflow) | |
382 | cpp_error (pfile, DL_PEDWARN, | |
383 | "integer constant is too large for its type"); | |
017acb41 NB |
384 | /* If too big to be signed, consider it unsigned. Only warn for |
385 | decimal numbers. Traditional numbers were always signed (but | |
8d9afc4e | 386 | we still honor an explicit U suffix); but we only have |
cd98faa1 | 387 | traditional semantics in directives. */ |
017acb41 | 388 | else if (!result.unsignedp |
cd98faa1 NB |
389 | && !(CPP_OPTION (pfile, traditional) |
390 | && pfile->state.in_directive) | |
017acb41 | 391 | && !num_positive (result, precision)) |
cd7ab83f | 392 | { |
cd7ab83f NB |
393 | if (base == 10) |
394 | cpp_error (pfile, DL_WARNING, | |
395 | "integer constant is so large that it is unsigned"); | |
23ff0223 | 396 | result.unsignedp = true; |
cd7ab83f NB |
397 | } |
398 | } | |
399 | ||
400 | return result; | |
401 | } | |
cf00a885 | 402 | |
91318908 NB |
403 | /* Append DIGIT to NUM, a number of PRECISION bits being read in base |
404 | BASE. */ | |
405 | static cpp_num | |
406 | append_digit (num, digit, base, precision) | |
407 | cpp_num num; | |
408 | int digit, base; | |
409 | size_t precision; | |
410 | { | |
411 | cpp_num result; | |
412 | unsigned int shift = 3 + (base == 16); | |
413 | bool overflow; | |
414 | cpp_num_part add_high, add_low; | |
415 | ||
416 | /* Multiply by 8 or 16. Catching this overflow here means we don't | |
417 | need to worry about add_high overflowing. */ | |
23ff0223 | 418 | overflow = !!(num.high >> (PART_PRECISION - shift)); |
91318908 NB |
419 | result.high = num.high << shift; |
420 | result.low = num.low << shift; | |
421 | result.high |= num.low >> (PART_PRECISION - shift); | |
422 | ||
423 | if (base == 10) | |
424 | { | |
425 | add_low = num.low << 1; | |
426 | add_high = (num.high << 1) + (num.low >> (PART_PRECISION - 1)); | |
427 | } | |
428 | else | |
429 | add_high = add_low = 0; | |
430 | ||
431 | if (add_low + digit < add_low) | |
432 | add_high++; | |
433 | add_low += digit; | |
434 | ||
435 | if (result.low + add_low < result.low) | |
436 | add_high++; | |
437 | if (result.high + add_high < result.high) | |
438 | overflow = true; | |
439 | ||
440 | result.low += add_low; | |
441 | result.high += add_high; | |
442 | ||
443 | /* The above code catches overflow of a cpp_num type. This catches | |
444 | overflow of the (possibly shorter) target precision. */ | |
445 | num.low = result.low; | |
446 | num.high = result.high; | |
447 | result = num_trim (result, precision); | |
448 | if (!num_eq (result, num)) | |
449 | overflow = true; | |
450 | ||
451 | result.unsignedp = num.unsignedp; | |
452 | result.overflow = overflow; | |
453 | return result; | |
454 | } | |
455 | ||
5d8ebbd8 | 456 | /* Handle meeting "defined" in a preprocessor expression. */ |
91318908 | 457 | static cpp_num |
ba412f14 ZW |
458 | parse_defined (pfile) |
459 | cpp_reader *pfile; | |
460 | { | |
91318908 | 461 | cpp_num result; |
93c80368 NB |
462 | int paren = 0; |
463 | cpp_hashnode *node = 0; | |
4ed5bcfb | 464 | const cpp_token *token; |
63d75005 | 465 | cpp_context *initial_context = pfile->context; |
ba412f14 | 466 | |
93c80368 NB |
467 | /* Don't expand macros. */ |
468 | pfile->state.prevent_expansion++; | |
469 | ||
4ed5bcfb NB |
470 | token = cpp_get_token (pfile); |
471 | if (token->type == CPP_OPEN_PAREN) | |
ba412f14 | 472 | { |
cf00a885 | 473 | paren = 1; |
4ed5bcfb | 474 | token = cpp_get_token (pfile); |
ba412f14 ZW |
475 | } |
476 | ||
4ed5bcfb | 477 | if (token->type == CPP_NAME) |
93c80368 | 478 | { |
4ed5bcfb NB |
479 | node = token->val.node; |
480 | if (paren && cpp_get_token (pfile)->type != CPP_CLOSE_PAREN) | |
93c80368 | 481 | { |
ebef4e8c | 482 | cpp_error (pfile, DL_ERROR, "missing ')' after \"defined\""); |
4ed5bcfb | 483 | node = 0; |
93c80368 NB |
484 | } |
485 | } | |
486 | else | |
3c8465d0 | 487 | { |
ebef4e8c NB |
488 | cpp_error (pfile, DL_ERROR, |
489 | "operator \"defined\" requires an identifier"); | |
4ed5bcfb | 490 | if (token->flags & NAMED_OP) |
3c8465d0 NB |
491 | { |
492 | cpp_token op; | |
493 | ||
494 | op.flags = 0; | |
4ed5bcfb | 495 | op.type = token->type; |
ebef4e8c | 496 | cpp_error (pfile, DL_ERROR, |
3c8465d0 | 497 | "(\"%s\" is an alternative token for \"%s\" in C++)", |
4ed5bcfb | 498 | cpp_token_as_text (pfile, token), |
3c8465d0 NB |
499 | cpp_token_as_text (pfile, &op)); |
500 | } | |
501 | } | |
15dad1d9 | 502 | |
91318908 | 503 | if (node) |
15dad1d9 | 504 | { |
63d75005 | 505 | if (pfile->context != initial_context) |
ebef4e8c NB |
506 | cpp_error (pfile, DL_WARNING, |
507 | "this use of \"defined\" may not be portable"); | |
63d75005 | 508 | |
a69cbaac NB |
509 | _cpp_mark_macro_used (node); |
510 | ||
6d18adbc NB |
511 | /* A possible controlling macro of the form #if !defined (). |
512 | _cpp_parse_expr checks there was no other junk on the line. */ | |
513 | pfile->mi_ind_cmacro = node; | |
15dad1d9 | 514 | } |
93c80368 NB |
515 | |
516 | pfile->state.prevent_expansion--; | |
91318908 | 517 | |
23ff0223 | 518 | result.unsignedp = false; |
91318908 | 519 | result.high = 0; |
23ff0223 | 520 | result.overflow = false; |
91318908 NB |
521 | result.low = node && node->type == NT_MACRO; |
522 | return result; | |
15dad1d9 ZW |
523 | } |
524 | ||
60284a59 NB |
525 | /* Convert a token into a CPP_NUMBER (an interpreted preprocessing |
526 | number or character constant, or the result of the "defined" or "#" | |
cd7ab83f | 527 | operators). */ |
91318908 | 528 | static cpp_num |
60284a59 | 529 | eval_token (pfile, token) |
52529158 | 530 | cpp_reader *pfile; |
60284a59 | 531 | const cpp_token *token; |
7f2935c7 | 532 | { |
91318908 | 533 | cpp_num result; |
60284a59 | 534 | unsigned int temp; |
4268e8bb | 535 | int unsignedp = 0; |
041c3194 | 536 | |
93c80368 | 537 | switch (token->type) |
ba412f14 | 538 | { |
7f2935c7 | 539 | case CPP_NUMBER: |
cd7ab83f NB |
540 | temp = cpp_classify_number (pfile, token); |
541 | switch (temp & CPP_N_CATEGORY) | |
542 | { | |
543 | case CPP_N_FLOATING: | |
544 | cpp_error (pfile, DL_ERROR, | |
545 | "floating constant in preprocessor expression"); | |
546 | break; | |
547 | case CPP_N_INTEGER: | |
548 | if (!(temp & CPP_N_IMAGINARY)) | |
549 | return cpp_interpret_integer (pfile, token, temp); | |
550 | cpp_error (pfile, DL_ERROR, | |
551 | "imaginary number in preprocessor expression"); | |
552 | break; | |
553 | ||
554 | case CPP_N_INVALID: | |
555 | /* Error already issued. */ | |
556 | break; | |
557 | } | |
558 | result.high = result.low = 0; | |
559 | break; | |
7f2f1a66 | 560 | |
cf00a885 | 561 | case CPP_WCHAR: |
4268e8bb | 562 | case CPP_CHAR: |
a5a49440 | 563 | { |
91318908 NB |
564 | cppchar_t cc = cpp_interpret_charconst (pfile, token, |
565 | &temp, &unsignedp); | |
566 | ||
567 | result.high = 0; | |
568 | result.low = cc; | |
a5a49440 | 569 | /* Sign-extend the result if necessary. */ |
91318908 NB |
570 | if (!unsignedp && (cppchar_signed_t) cc < 0) |
571 | { | |
572 | if (PART_PRECISION > BITS_PER_CPPCHAR_T) | |
573 | result.low |= ~(~(cpp_num_part) 0 | |
574 | >> (PART_PRECISION - BITS_PER_CPPCHAR_T)); | |
575 | result.high = ~(cpp_num_part) 0; | |
576 | result = num_trim (result, CPP_OPTION (pfile, precision)); | |
577 | } | |
a5a49440 | 578 | } |
60284a59 | 579 | break; |
ba412f14 | 580 | |
92936ecf | 581 | case CPP_NAME: |
93c80368 | 582 | if (token->val.node == pfile->spec_nodes.n_defined) |
63d75005 | 583 | return parse_defined (pfile); |
7d4918a2 ZW |
584 | else if (CPP_OPTION (pfile, cplusplus) |
585 | && (token->val.node == pfile->spec_nodes.n_true | |
586 | || token->val.node == pfile->spec_nodes.n_false)) | |
587 | { | |
91318908 NB |
588 | result.high = 0; |
589 | result.low = (token->val.node == pfile->spec_nodes.n_true); | |
7d4918a2 ZW |
590 | |
591 | /* Warn about use of true or false in #if when pedantic | |
592 | and stdbool.h has not been included. */ | |
593 | if (CPP_PEDANTIC (pfile) | |
594 | && ! cpp_defined (pfile, DSC("__bool_true_false_are_defined"))) | |
ebef4e8c NB |
595 | cpp_error (pfile, DL_PEDWARN, |
596 | "ISO C++ does not permit \"%s\" in #if", | |
597 | NODE_NAME (token->val.node)); | |
7d4918a2 ZW |
598 | } |
599 | else | |
600 | { | |
91318908 NB |
601 | result.high = 0; |
602 | result.low = 0; | |
87ed109f | 603 | if (CPP_OPTION (pfile, warn_undef) && !pfile->state.skip_eval) |
ebef4e8c NB |
604 | cpp_error (pfile, DL_WARNING, "\"%s\" is not defined", |
605 | NODE_NAME (token->val.node)); | |
7f2935c7 | 606 | } |
60284a59 | 607 | break; |
7f2935c7 | 608 | |
60284a59 | 609 | default: /* CPP_HASH */ |
91318908 NB |
610 | _cpp_test_assertion (pfile, &temp); |
611 | result.high = 0; | |
612 | result.low = temp; | |
93c80368 | 613 | } |
7c3bb1de | 614 | |
23ff0223 NB |
615 | result.unsignedp = !!unsignedp; |
616 | result.overflow = false; | |
91318908 | 617 | return result; |
7f2935c7 PB |
618 | } |
619 | \f | |
4063b943 | 620 | /* Operator precedence and flags table. |
dbac4aff NB |
621 | |
622 | After an operator is returned from the lexer, if it has priority less | |
87ed109f NB |
623 | than the operator on the top of the stack, we reduce the stack by one |
624 | operator and repeat the test. Since equal priorities do not reduce, | |
625 | this is naturally right-associative. | |
626 | ||
627 | We handle left-associative operators by decrementing the priority of | |
628 | just-lexed operators by one, but retaining the priority of operators | |
629 | already on the stack. | |
dbac4aff NB |
630 | |
631 | The remaining cases are '(' and ')'. We handle '(' by skipping the | |
632 | reduction phase completely. ')' is given lower priority than | |
633 | everything else, including '(', effectively forcing a reduction of the | |
87ed109f NB |
634 | parenthesised expression. If there is a matching '(', the routine |
635 | reduce() exits immediately. If the normal exit route sees a ')', then | |
636 | there cannot have been a matching '(' and an error message is output. | |
4063b943 | 637 | |
f8b954fc NB |
638 | The parser assumes all shifted operators require a left operand unless |
639 | the flag NO_L_OPERAND is set. These semantics are automatic; any | |
640 | extra semantics need to be handled with operator-specific code. */ | |
4063b943 | 641 | |
68e65275 NB |
642 | /* Flags. If CHECK_PROMOTION, we warn if the effective sign of an |
643 | operand changes because of integer promotions. */ | |
87ed109f NB |
644 | #define NO_L_OPERAND (1 << 0) |
645 | #define LEFT_ASSOC (1 << 1) | |
68e65275 | 646 | #define CHECK_PROMOTION (1 << 2) |
eba30526 | 647 | |
cf00a885 ZW |
648 | /* Operator to priority map. Must be in the same order as the first |
649 | N entries of enum cpp_ttype. */ | |
87ed109f NB |
650 | static const struct operator |
651 | { | |
60284a59 | 652 | uchar prio; |
87ed109f NB |
653 | uchar flags; |
654 | } optab[] = | |
cf00a885 | 655 | { |
ad28cff7 NB |
656 | /* EQ */ {0, 0}, /* Shouldn't happen. */ |
657 | /* NOT */ {16, NO_L_OPERAND}, | |
68e65275 NB |
658 | /* GREATER */ {12, LEFT_ASSOC | CHECK_PROMOTION}, |
659 | /* LESS */ {12, LEFT_ASSOC | CHECK_PROMOTION}, | |
660 | /* PLUS */ {14, LEFT_ASSOC | CHECK_PROMOTION}, | |
661 | /* MINUS */ {14, LEFT_ASSOC | CHECK_PROMOTION}, | |
662 | /* MULT */ {15, LEFT_ASSOC | CHECK_PROMOTION}, | |
663 | /* DIV */ {15, LEFT_ASSOC | CHECK_PROMOTION}, | |
664 | /* MOD */ {15, LEFT_ASSOC | CHECK_PROMOTION}, | |
665 | /* AND */ {9, LEFT_ASSOC | CHECK_PROMOTION}, | |
666 | /* OR */ {7, LEFT_ASSOC | CHECK_PROMOTION}, | |
667 | /* XOR */ {8, LEFT_ASSOC | CHECK_PROMOTION}, | |
ad28cff7 NB |
668 | /* RSHIFT */ {13, LEFT_ASSOC}, |
669 | /* LSHIFT */ {13, LEFT_ASSOC}, | |
670 | ||
68e65275 NB |
671 | /* MIN */ {10, LEFT_ASSOC | CHECK_PROMOTION}, |
672 | /* MAX */ {10, LEFT_ASSOC | CHECK_PROMOTION}, | |
ad28cff7 NB |
673 | |
674 | /* COMPL */ {16, NO_L_OPERAND}, | |
75aef48a NB |
675 | /* AND_AND */ {6, LEFT_ASSOC}, |
676 | /* OR_OR */ {5, LEFT_ASSOC}, | |
677 | /* QUERY */ {3, 0}, | |
68e65275 | 678 | /* COLON */ {4, LEFT_ASSOC | CHECK_PROMOTION}, |
ad28cff7 | 679 | /* COMMA */ {2, LEFT_ASSOC}, |
75aef48a | 680 | /* OPEN_PAREN */ {1, NO_L_OPERAND}, |
ad28cff7 NB |
681 | /* CLOSE_PAREN */ {0, 0}, |
682 | /* EOF */ {0, 0}, | |
683 | /* EQ_EQ */ {11, LEFT_ASSOC}, | |
684 | /* NOT_EQ */ {11, LEFT_ASSOC}, | |
68e65275 NB |
685 | /* GREATER_EQ */ {12, LEFT_ASSOC | CHECK_PROMOTION}, |
686 | /* LESS_EQ */ {12, LEFT_ASSOC | CHECK_PROMOTION}, | |
ad28cff7 NB |
687 | /* UPLUS */ {16, NO_L_OPERAND}, |
688 | /* UMINUS */ {16, NO_L_OPERAND} | |
cf00a885 ZW |
689 | }; |
690 | ||
7f2935c7 | 691 | /* Parse and evaluate a C expression, reading from PFILE. |
df383483 | 692 | Returns the truth value of the expression. |
87ed109f NB |
693 | |
694 | The implementation is an operator precedence parser, i.e. a | |
695 | bottom-up parser, using a stack for not-yet-reduced tokens. | |
696 | ||
697 | The stack base is op_stack, and the current stack pointer is 'top'. | |
698 | There is a stack element for each operator (only), and the most | |
699 | recently pushed operator is 'top->op'. An operand (value) is | |
700 | stored in the 'value' field of the stack element of the operator | |
701 | that precedes it. */ | |
702 | bool | |
b0699dad | 703 | _cpp_parse_expr (pfile) |
7f2935c7 PB |
704 | cpp_reader *pfile; |
705 | { | |
87ed109f NB |
706 | struct op *top = pfile->op_stack; |
707 | unsigned int lex_count; | |
708 | bool saw_leading_not, want_value = true; | |
709 | ||
710 | pfile->state.skip_eval = 0; | |
7f2935c7 | 711 | |
93c80368 | 712 | /* Set up detection of #if ! defined(). */ |
6d18adbc | 713 | pfile->mi_ind_cmacro = 0; |
87ed109f | 714 | saw_leading_not = false; |
6d18adbc | 715 | lex_count = 0; |
93c80368 | 716 | |
87ed109f | 717 | /* Lowest priority operator prevents further reductions. */ |
cf00a885 | 718 | top->op = CPP_EOF; |
4063b943 | 719 | |
7f2935c7 PB |
720 | for (;;) |
721 | { | |
cf00a885 | 722 | struct op op; |
7f2935c7 | 723 | |
6d18adbc | 724 | lex_count++; |
68e65275 NB |
725 | op.token = cpp_get_token (pfile); |
726 | op.op = op.token->type; | |
7f2935c7 | 727 | |
7f2935c7 PB |
728 | switch (op.op) |
729 | { | |
60284a59 | 730 | /* These tokens convert into values. */ |
c60e94a7 | 731 | case CPP_NUMBER: |
60284a59 NB |
732 | case CPP_CHAR: |
733 | case CPP_WCHAR: | |
734 | case CPP_NAME: | |
735 | case CPP_HASH: | |
f8b954fc | 736 | if (!want_value) |
60284a59 | 737 | SYNTAX_ERROR2 ("missing binary operator before token \"%s\"", |
68e65275 | 738 | cpp_token_as_text (pfile, op.token)); |
f8b954fc | 739 | want_value = false; |
68e65275 | 740 | top->value = eval_token (pfile, op.token); |
9ee70313 NB |
741 | continue; |
742 | ||
6d18adbc NB |
743 | case CPP_NOT: |
744 | saw_leading_not = lex_count == 1; | |
6d18adbc | 745 | break; |
cf00a885 | 746 | case CPP_PLUS: |
f8b954fc NB |
747 | if (want_value) |
748 | op.op = CPP_UPLUS; | |
749 | break; | |
750 | case CPP_MINUS: | |
751 | if (want_value) | |
752 | op.op = CPP_UMINUS; | |
753 | break; | |
60284a59 | 754 | case CPP_OTHER: |
68e65275 NB |
755 | if (ISGRAPH (op.token->val.c)) |
756 | SYNTAX_ERROR2 ("invalid character '%c' in #if", op.token->val.c); | |
60284a59 | 757 | else |
68e65275 NB |
758 | SYNTAX_ERROR2 ("invalid character '\\%03o' in #if", |
759 | op.token->val.c); | |
60284a59 | 760 | |
f8b954fc | 761 | default: |
60284a59 | 762 | if ((int) op.op <= (int) CPP_EQ || (int) op.op >= (int) CPP_PLUS_EQ) |
cd7ab83f | 763 | SYNTAX_ERROR2 ("token \"%s\" is not valid in preprocessor expressions", |
68e65275 | 764 | cpp_token_as_text (pfile, op.token)); |
f8b954fc | 765 | break; |
7f2935c7 | 766 | } |
7f2935c7 | 767 | |
87ed109f NB |
768 | /* Check we have a value or operator as appropriate. */ |
769 | if (optab[op.op].flags & NO_L_OPERAND) | |
7f2935c7 | 770 | { |
87ed109f | 771 | if (!want_value) |
60284a59 | 772 | SYNTAX_ERROR2 ("missing binary operator before token \"%s\"", |
68e65275 | 773 | cpp_token_as_text (pfile, op.token)); |
87ed109f NB |
774 | } |
775 | else if (want_value) | |
776 | { | |
8d9afc4e | 777 | /* Ordering here is subtle and intended to favor the |
60284a59 | 778 | missing parenthesis diagnostics over alternatives. */ |
87ed109f | 779 | if (op.op == CPP_CLOSE_PAREN) |
7f2935c7 | 780 | { |
cf00a885 | 781 | if (top->op == CPP_OPEN_PAREN) |
b22ef131 | 782 | SYNTAX_ERROR ("void expression between '(' and ')'"); |
7f2935c7 | 783 | } |
87ed109f NB |
784 | else if (top->op == CPP_EOF) |
785 | SYNTAX_ERROR ("#if with no expression"); | |
786 | if (top->op != CPP_EOF && top->op != CPP_OPEN_PAREN) | |
787 | SYNTAX_ERROR2 ("operator '%s' has no right operand", | |
68e65275 | 788 | cpp_token_as_text (pfile, top->token)); |
7f2935c7 | 789 | } |
9ee70313 | 790 | |
87ed109f NB |
791 | top = reduce (pfile, top, op.op); |
792 | if (!top) | |
793 | goto syntax_error; | |
9ee70313 | 794 | |
60284a59 NB |
795 | if (op.op == CPP_EOF) |
796 | break; | |
797 | ||
87ed109f | 798 | switch (op.op) |
b22ef131 | 799 | { |
87ed109f NB |
800 | case CPP_CLOSE_PAREN: |
801 | continue; | |
87ed109f | 802 | case CPP_OR_OR: |
91318908 | 803 | if (!num_zerop (top->value)) |
87ed109f NB |
804 | pfile->state.skip_eval++; |
805 | break; | |
806 | case CPP_AND_AND: | |
807 | case CPP_QUERY: | |
91318908 | 808 | if (num_zerop (top->value)) |
87ed109f NB |
809 | pfile->state.skip_eval++; |
810 | break; | |
811 | case CPP_COLON: | |
60284a59 NB |
812 | if (top->op != CPP_QUERY) |
813 | SYNTAX_ERROR (" ':' without preceding '?'"); | |
91318908 | 814 | if (!num_zerop (top[-1].value)) /* Was '?' condition true? */ |
87ed109f NB |
815 | pfile->state.skip_eval++; |
816 | else | |
817 | pfile->state.skip_eval--; | |
818 | default: | |
819 | break; | |
4063b943 | 820 | } |
87ed109f | 821 | |
f8b954fc | 822 | want_value = true; |
4063b943 | 823 | |
0f41302f | 824 | /* Check for and handle stack overflow. */ |
87ed109f NB |
825 | if (++top == pfile->op_limit) |
826 | top = _cpp_expand_op_stack (pfile); | |
df383483 | 827 | |
7f2935c7 | 828 | top->op = op.op; |
68e65275 | 829 | top->token = op.token; |
7f2935c7 | 830 | } |
9ee70313 | 831 | |
6d18adbc NB |
832 | /* The controlling macro expression is only valid if we called lex 3 |
833 | times: <!> <defined expression> and <EOF>. push_conditional () | |
834 | checks that we are at top-of-file. */ | |
835 | if (pfile->mi_ind_cmacro && !(saw_leading_not && lex_count == 3)) | |
836 | pfile->mi_ind_cmacro = 0; | |
837 | ||
87ed109f | 838 | if (top != pfile->op_stack) |
ebef4e8c NB |
839 | { |
840 | cpp_error (pfile, DL_ICE, "unbalanced stack in #if"); | |
4063b943 | 841 | syntax_error: |
87ed109f | 842 | return false; /* Return false on syntax error. */ |
4063b943 | 843 | } |
9ee70313 | 844 | |
91318908 | 845 | return !num_zerop (top->value); |
87ed109f NB |
846 | } |
847 | ||
848 | /* Reduce the operator / value stack if possible, in preparation for | |
849 | pushing operator OP. Returns NULL on error, otherwise the top of | |
850 | the stack. */ | |
851 | static struct op * | |
852 | reduce (pfile, top, op) | |
853 | cpp_reader *pfile; | |
854 | struct op *top; | |
855 | enum cpp_ttype op; | |
856 | { | |
857 | unsigned int prio; | |
858 | ||
91318908 NB |
859 | if (top->op <= CPP_EQ || top->op > CPP_LAST_CPP_OP + 2) |
860 | { | |
861 | bad_op: | |
862 | cpp_error (pfile, DL_ICE, "impossible operator '%u'", top->op); | |
863 | return 0; | |
864 | } | |
865 | ||
87ed109f NB |
866 | if (op == CPP_OPEN_PAREN) |
867 | return top; | |
868 | ||
869 | /* Decrement the priority of left-associative operators to force a | |
870 | reduction with operators of otherwise equal priority. */ | |
871 | prio = optab[op].prio - ((optab[op].flags & LEFT_ASSOC) != 0); | |
872 | while (prio < optab[top->op].prio) | |
873 | { | |
68e65275 NB |
874 | if (CPP_OPTION (pfile, warn_num_sign_change) |
875 | && optab[top->op].flags & CHECK_PROMOTION) | |
876 | check_promotion (pfile, top); | |
877 | ||
75aef48a NB |
878 | switch (top->op) |
879 | { | |
880 | case CPP_UPLUS: | |
881 | case CPP_UMINUS: | |
882 | case CPP_NOT: | |
883 | case CPP_COMPL: | |
884 | top[-1].value = num_unary_op (pfile, top->value, top->op); | |
885 | break; | |
87ed109f | 886 | |
75aef48a NB |
887 | case CPP_PLUS: |
888 | case CPP_MINUS: | |
889 | case CPP_RSHIFT: | |
890 | case CPP_LSHIFT: | |
891 | case CPP_MIN: | |
892 | case CPP_MAX: | |
893 | case CPP_COMMA: | |
894 | top[-1].value = num_binary_op (pfile, top[-1].value, | |
895 | top->value, top->op); | |
896 | break; | |
91318908 | 897 | |
75aef48a NB |
898 | case CPP_GREATER: |
899 | case CPP_LESS: | |
900 | case CPP_GREATER_EQ: | |
901 | case CPP_LESS_EQ: | |
902 | top[-1].value | |
903 | = num_inequality_op (pfile, top[-1].value, top->value, top->op); | |
904 | break; | |
91318908 | 905 | |
75aef48a NB |
906 | case CPP_EQ_EQ: |
907 | case CPP_NOT_EQ: | |
908 | top[-1].value | |
909 | = num_equality_op (pfile, top[-1].value, top->value, top->op); | |
910 | break; | |
87ed109f | 911 | |
75aef48a NB |
912 | case CPP_AND: |
913 | case CPP_OR: | |
914 | case CPP_XOR: | |
915 | top[-1].value | |
916 | = num_bitwise_op (pfile, top[-1].value, top->value, top->op); | |
917 | break; | |
91318908 | 918 | |
75aef48a NB |
919 | case CPP_MULT: |
920 | top[-1].value = num_mul (pfile, top[-1].value, top->value); | |
921 | break; | |
ad28cff7 | 922 | |
75aef48a NB |
923 | case CPP_DIV: |
924 | case CPP_MOD: | |
925 | top[-1].value = num_div_op (pfile, top[-1].value, | |
926 | top->value, top->op); | |
927 | break; | |
ad28cff7 | 928 | |
75aef48a NB |
929 | case CPP_OR_OR: |
930 | top--; | |
931 | if (!num_zerop (top->value)) | |
932 | pfile->state.skip_eval--; | |
933 | top->value.low = (!num_zerop (top->value) | |
934 | || !num_zerop (top[1].value)); | |
935 | top->value.high = 0; | |
936 | top->value.unsignedp = false; | |
937 | top->value.overflow = false; | |
938 | continue; | |
939 | ||
940 | case CPP_AND_AND: | |
941 | top--; | |
942 | if (num_zerop (top->value)) | |
943 | pfile->state.skip_eval--; | |
944 | top->value.low = (!num_zerop (top->value) | |
945 | && !num_zerop (top[1].value)); | |
946 | top->value.high = 0; | |
947 | top->value.unsignedp = false; | |
948 | top->value.overflow = false; | |
949 | continue; | |
950 | ||
951 | case CPP_OPEN_PAREN: | |
952 | if (op != CPP_CLOSE_PAREN) | |
953 | { | |
954 | cpp_error (pfile, DL_ERROR, "missing ')' in expression"); | |
955 | return 0; | |
956 | } | |
957 | top--; | |
958 | top->value = top[1].value; | |
959 | return top; | |
960 | ||
961 | case CPP_COLON: | |
962 | top -= 2; | |
963 | if (!num_zerop (top->value)) | |
964 | { | |
ad28cff7 | 965 | pfile->state.skip_eval--; |
75aef48a NB |
966 | top->value = top[1].value; |
967 | } | |
968 | else | |
969 | top->value = top[2].value; | |
970 | top->value.unsignedp = (top[1].value.unsignedp | |
971 | || top[2].value.unsignedp); | |
972 | continue; | |
973 | ||
974 | case CPP_QUERY: | |
975 | cpp_error (pfile, DL_ERROR, "'?' without following ':'"); | |
976 | return 0; | |
977 | ||
978 | default: | |
979 | goto bad_op; | |
980 | } | |
91318908 | 981 | |
ad28cff7 | 982 | top--; |
91318908 NB |
983 | if (top->value.overflow && !pfile->state.skip_eval) |
984 | cpp_error (pfile, DL_PEDWARN, | |
985 | "integer overflow in preprocessor expression"); | |
87ed109f NB |
986 | } |
987 | ||
988 | if (op == CPP_CLOSE_PAREN) | |
989 | { | |
990 | cpp_error (pfile, DL_ERROR, "missing '(' in expression"); | |
991 | return 0; | |
992 | } | |
993 | ||
994 | return top; | |
995 | } | |
996 | ||
997 | /* Returns the position of the old top of stack after expansion. */ | |
998 | struct op * | |
999 | _cpp_expand_op_stack (pfile) | |
1000 | cpp_reader *pfile; | |
1001 | { | |
32fa4565 NB |
1002 | size_t old_size = (size_t) (pfile->op_limit - pfile->op_stack); |
1003 | size_t new_size = old_size * 2 + 20; | |
87ed109f NB |
1004 | |
1005 | pfile->op_stack = (struct op *) xrealloc (pfile->op_stack, | |
32fa4565 NB |
1006 | new_size * sizeof (struct op)); |
1007 | pfile->op_limit = pfile->op_stack + new_size; | |
87ed109f | 1008 | |
32fa4565 | 1009 | return pfile->op_stack + old_size; |
7f2935c7 | 1010 | } |
91318908 | 1011 | |
68e65275 NB |
1012 | /* Emits a warning if the effective sign of either operand of OP |
1013 | changes because of integer promotions. */ | |
1014 | static void | |
1015 | check_promotion (pfile, op) | |
1016 | cpp_reader *pfile; | |
1017 | const struct op *op; | |
1018 | { | |
1019 | if (op->value.unsignedp == op[-1].value.unsignedp) | |
1020 | return; | |
1021 | ||
1022 | if (op->value.unsignedp) | |
1023 | { | |
1024 | if (!num_positive (op[-1].value, CPP_OPTION (pfile, precision))) | |
1025 | cpp_error (pfile, DL_WARNING, | |
1026 | "the left operand of \"%s\" changes sign when promoted", | |
1027 | cpp_token_as_text (pfile, op->token)); | |
1028 | } | |
1029 | else if (!num_positive (op->value, CPP_OPTION (pfile, precision))) | |
1030 | cpp_error (pfile, DL_WARNING, | |
1031 | "the right operand of \"%s\" changes sign when promoted", | |
1032 | cpp_token_as_text (pfile, op->token)); | |
1033 | } | |
1034 | ||
91318908 NB |
1035 | /* Clears the unused high order bits of the number pointed to by PNUM. */ |
1036 | static cpp_num | |
1037 | num_trim (num, precision) | |
1038 | cpp_num num; | |
1039 | size_t precision; | |
1040 | { | |
1041 | if (precision > PART_PRECISION) | |
1042 | { | |
1043 | precision -= PART_PRECISION; | |
1044 | if (precision < PART_PRECISION) | |
359b0bec | 1045 | num.high &= ((cpp_num_part) 1 << precision) - 1; |
91318908 NB |
1046 | } |
1047 | else | |
1048 | { | |
1049 | if (precision < PART_PRECISION) | |
359b0bec | 1050 | num.low &= ((cpp_num_part) 1 << precision) - 1; |
91318908 NB |
1051 | num.high = 0; |
1052 | } | |
1053 | ||
1054 | return num; | |
1055 | } | |
1056 | ||
1057 | /* True iff A (presumed signed) >= 0. */ | |
1058 | static bool | |
1059 | num_positive (num, precision) | |
1060 | cpp_num num; | |
1061 | size_t precision; | |
1062 | { | |
1063 | if (precision > PART_PRECISION) | |
1064 | { | |
1065 | precision -= PART_PRECISION; | |
359b0bec | 1066 | return (num.high & (cpp_num_part) 1 << (precision - 1)) == 0; |
91318908 NB |
1067 | } |
1068 | ||
359b0bec | 1069 | return (num.low & (cpp_num_part) 1 << (precision - 1)) == 0; |
91318908 NB |
1070 | } |
1071 | ||
ceeedfc1 NB |
1072 | /* Sign extend a number, with PRECISION significant bits and all |
1073 | others assumed clear, to fill out a cpp_num structure. */ | |
1074 | cpp_num | |
1075 | cpp_num_sign_extend (num, precision) | |
1076 | cpp_num num; | |
1077 | size_t precision; | |
1078 | { | |
1079 | if (!num.unsignedp) | |
1080 | { | |
1081 | if (precision > PART_PRECISION) | |
1082 | { | |
1083 | precision -= PART_PRECISION; | |
1084 | if (precision < PART_PRECISION | |
1085 | && (num.high & (cpp_num_part) 1 << (precision - 1))) | |
1086 | num.high |= ~(~(cpp_num_part) 0 >> (PART_PRECISION - precision)); | |
1087 | } | |
1088 | else if (num.low & (cpp_num_part) 1 << (precision - 1)) | |
1089 | { | |
1090 | if (precision < PART_PRECISION) | |
1091 | num.low |= ~(~(cpp_num_part) 0 >> (PART_PRECISION - precision)); | |
1092 | num.high = ~(cpp_num_part) 0; | |
1093 | } | |
1094 | } | |
1095 | ||
1096 | return num; | |
1097 | } | |
1098 | ||
91318908 NB |
1099 | /* Returns the negative of NUM. */ |
1100 | static cpp_num | |
1101 | num_negate (num, precision) | |
1102 | cpp_num num; | |
1103 | size_t precision; | |
1104 | { | |
1105 | cpp_num copy; | |
1106 | ||
1107 | copy = num; | |
1108 | num.high = ~num.high; | |
1109 | num.low = ~num.low; | |
1110 | if (++num.low == 0) | |
1111 | num.high++; | |
1112 | num = num_trim (num, precision); | |
1113 | num.overflow = (!num.unsignedp && num_eq (num, copy) && !num_zerop (num)); | |
1114 | ||
1115 | return num; | |
1116 | } | |
1117 | ||
1118 | /* Returns true if A >= B. */ | |
1119 | static bool | |
1120 | num_greater_eq (pa, pb, precision) | |
1121 | cpp_num pa, pb; | |
1122 | size_t precision; | |
1123 | { | |
1124 | bool unsignedp; | |
1125 | ||
1126 | unsignedp = pa.unsignedp || pb.unsignedp; | |
1127 | ||
1128 | if (!unsignedp) | |
1129 | { | |
1130 | /* Both numbers have signed type. If they are of different | |
1131 | sign, the answer is the sign of A. */ | |
1132 | unsignedp = num_positive (pa, precision); | |
1133 | ||
1134 | if (unsignedp != num_positive (pb, precision)) | |
1135 | return unsignedp; | |
1136 | ||
1137 | /* Otherwise we can do an unsigned comparison. */ | |
1138 | } | |
1139 | ||
1140 | return (pa.high > pb.high) || (pa.high == pb.high && pa.low >= pb.low); | |
1141 | } | |
1142 | ||
1143 | /* Returns LHS OP RHS, where OP is a bit-wise operation. */ | |
1144 | static cpp_num | |
1145 | num_bitwise_op (pfile, lhs, rhs, op) | |
1146 | cpp_reader *pfile ATTRIBUTE_UNUSED; | |
1147 | cpp_num lhs, rhs; | |
1148 | enum cpp_ttype op; | |
1149 | { | |
1150 | lhs.overflow = false; | |
1151 | lhs.unsignedp = lhs.unsignedp || rhs.unsignedp; | |
1152 | ||
1153 | /* As excess precision is zeroed, there is no need to num_trim () as | |
1154 | these operations cannot introduce a set bit there. */ | |
1155 | if (op == CPP_AND) | |
1156 | { | |
1157 | lhs.low &= rhs.low; | |
1158 | lhs.high &= rhs.high; | |
1159 | } | |
1160 | else if (op == CPP_OR) | |
1161 | { | |
1162 | lhs.low |= rhs.low; | |
1163 | lhs.high |= rhs.high; | |
1164 | } | |
1165 | else | |
1166 | { | |
1167 | lhs.low ^= rhs.low; | |
1168 | lhs.high ^= rhs.high; | |
1169 | } | |
1170 | ||
1171 | return lhs; | |
1172 | } | |
1173 | ||
1174 | /* Returns LHS OP RHS, where OP is an inequality. */ | |
1175 | static cpp_num | |
1176 | num_inequality_op (pfile, lhs, rhs, op) | |
1177 | cpp_reader *pfile; | |
1178 | cpp_num lhs, rhs; | |
1179 | enum cpp_ttype op; | |
1180 | { | |
1181 | bool gte = num_greater_eq (lhs, rhs, CPP_OPTION (pfile, precision)); | |
1182 | ||
1183 | if (op == CPP_GREATER_EQ) | |
1184 | lhs.low = gte; | |
1185 | else if (op == CPP_LESS) | |
1186 | lhs.low = !gte; | |
1187 | else if (op == CPP_GREATER) | |
1188 | lhs.low = gte && !num_eq (lhs, rhs); | |
1189 | else /* CPP_LESS_EQ. */ | |
1190 | lhs.low = !gte || num_eq (lhs, rhs); | |
1191 | ||
1192 | lhs.high = 0; | |
1193 | lhs.overflow = false; | |
1194 | lhs.unsignedp = false; | |
1195 | return lhs; | |
1196 | } | |
1197 | ||
1198 | /* Returns LHS OP RHS, where OP is == or !=. */ | |
1199 | static cpp_num | |
1200 | num_equality_op (pfile, lhs, rhs, op) | |
1201 | cpp_reader *pfile ATTRIBUTE_UNUSED; | |
1202 | cpp_num lhs, rhs; | |
1203 | enum cpp_ttype op; | |
1204 | { | |
97459791 JM |
1205 | /* Work around a 3.0.4 bug; see PR 6950. */ |
1206 | bool eq = num_eq (lhs, rhs); | |
91318908 | 1207 | if (op == CPP_NOT_EQ) |
97459791 JM |
1208 | eq = !eq; |
1209 | lhs.low = eq; | |
91318908 NB |
1210 | lhs.high = 0; |
1211 | lhs.overflow = false; | |
1212 | lhs.unsignedp = false; | |
1213 | return lhs; | |
1214 | } | |
1215 | ||
1216 | /* Shift NUM, of width PRECISION, right by N bits. */ | |
1217 | static cpp_num | |
1218 | num_rshift (num, precision, n) | |
1219 | cpp_num num; | |
1220 | size_t precision, n; | |
1221 | { | |
1222 | cpp_num_part sign_mask; | |
1223 | ||
1224 | if (num.unsignedp || num_positive (num, precision)) | |
1225 | sign_mask = 0; | |
1226 | else | |
1227 | sign_mask = ~(cpp_num_part) 0; | |
1228 | ||
1229 | if (n >= precision) | |
1230 | num.high = num.low = sign_mask; | |
1231 | else | |
1232 | { | |
1233 | /* Sign-extend. */ | |
1234 | if (precision < PART_PRECISION) | |
1235 | num.high = sign_mask, num.low |= sign_mask << precision; | |
1236 | else if (precision < 2 * PART_PRECISION) | |
1237 | num.high |= sign_mask << (precision - PART_PRECISION); | |
1238 | ||
1239 | if (n >= PART_PRECISION) | |
1240 | { | |
1241 | n -= PART_PRECISION; | |
1242 | num.low = num.high; | |
1243 | num.high = sign_mask; | |
1244 | } | |
1245 | ||
1246 | if (n) | |
1247 | { | |
1248 | num.low = (num.low >> n) | (num.high << (PART_PRECISION - n)); | |
1249 | num.high = (num.high >> n) | (sign_mask << (PART_PRECISION - n)); | |
1250 | } | |
1251 | } | |
1252 | ||
1253 | num = num_trim (num, precision); | |
1254 | num.overflow = false; | |
1255 | return num; | |
1256 | } | |
1257 | ||
1258 | /* Shift NUM, of width PRECISION, left by N bits. */ | |
1259 | static cpp_num | |
1260 | num_lshift (num, precision, n) | |
1261 | cpp_num num; | |
1262 | size_t precision, n; | |
1263 | { | |
1264 | if (n >= precision) | |
1265 | { | |
1266 | num.overflow = !num.unsignedp && !num_zerop (num); | |
1267 | num.high = num.low = 0; | |
1268 | } | |
1269 | else | |
1270 | { | |
1271 | cpp_num orig, maybe_orig; | |
1272 | size_t m = n; | |
1273 | ||
1274 | orig = num; | |
1275 | if (m >= PART_PRECISION) | |
1276 | { | |
1277 | m -= PART_PRECISION; | |
1278 | num.high = num.low; | |
1279 | num.low = 0; | |
1280 | } | |
1281 | if (m) | |
1282 | { | |
1283 | num.high = (num.high << m) | (num.low >> (PART_PRECISION - m)); | |
1284 | num.low <<= m; | |
1285 | } | |
1286 | num = num_trim (num, precision); | |
1287 | ||
1288 | if (num.unsignedp) | |
1289 | num.overflow = false; | |
1290 | else | |
1291 | { | |
1292 | maybe_orig = num_rshift (num, precision, n); | |
1293 | num.overflow = !num_eq (orig, maybe_orig); | |
1294 | } | |
1295 | } | |
1296 | ||
1297 | return num; | |
1298 | } | |
1299 | ||
1300 | /* The four unary operators: +, -, ! and ~. */ | |
1301 | static cpp_num | |
1302 | num_unary_op (pfile, num, op) | |
1303 | cpp_reader *pfile; | |
1304 | cpp_num num; | |
1305 | enum cpp_ttype op; | |
1306 | { | |
1307 | switch (op) | |
1308 | { | |
1309 | case CPP_UPLUS: | |
75aef48a | 1310 | if (CPP_WTRADITIONAL (pfile) && !pfile->state.skip_eval) |
91318908 NB |
1311 | cpp_error (pfile, DL_WARNING, |
1312 | "traditional C rejects the unary plus operator"); | |
1313 | num.overflow = false; | |
1314 | break; | |
1315 | ||
1316 | case CPP_UMINUS: | |
1317 | num = num_negate (num, CPP_OPTION (pfile, precision)); | |
1318 | break; | |
1319 | ||
1320 | case CPP_COMPL: | |
1321 | num.high = ~num.high; | |
1322 | num.low = ~num.low; | |
1323 | num = num_trim (num, CPP_OPTION (pfile, precision)); | |
1324 | num.overflow = false; | |
1325 | break; | |
1326 | ||
1327 | default: /* case CPP_NOT: */ | |
1328 | num.low = num_zerop (num); | |
1329 | num.high = 0; | |
1330 | num.overflow = false; | |
1331 | num.unsignedp = false; | |
1332 | break; | |
1333 | } | |
1334 | ||
1335 | return num; | |
1336 | } | |
1337 | ||
1338 | /* The various binary operators. */ | |
1339 | static cpp_num | |
1340 | num_binary_op (pfile, lhs, rhs, op) | |
1341 | cpp_reader *pfile; | |
1342 | cpp_num lhs, rhs; | |
1343 | enum cpp_ttype op; | |
1344 | { | |
1345 | cpp_num result; | |
1346 | size_t precision = CPP_OPTION (pfile, precision); | |
1347 | bool gte; | |
1348 | size_t n; | |
1349 | ||
1350 | switch (op) | |
1351 | { | |
1352 | /* Shifts. */ | |
1353 | case CPP_LSHIFT: | |
1354 | case CPP_RSHIFT: | |
1355 | if (!rhs.unsignedp && !num_positive (rhs, precision)) | |
1356 | { | |
1357 | /* A negative shift is a positive shift the other way. */ | |
1358 | if (op == CPP_LSHIFT) | |
1359 | op = CPP_RSHIFT; | |
1360 | else | |
1361 | op = CPP_LSHIFT; | |
1362 | rhs = num_negate (rhs, precision); | |
1363 | } | |
1364 | if (rhs.high) | |
1365 | n = ~0; /* Maximal. */ | |
1366 | else | |
1367 | n = rhs.low; | |
1368 | if (op == CPP_LSHIFT) | |
1369 | lhs = num_lshift (lhs, precision, n); | |
1370 | else | |
1371 | lhs = num_rshift (lhs, precision, n); | |
1372 | break; | |
1373 | ||
1374 | /* Min / Max. */ | |
1375 | case CPP_MIN: | |
1376 | case CPP_MAX: | |
1377 | { | |
1378 | bool unsignedp = lhs.unsignedp || rhs.unsignedp; | |
1379 | ||
1380 | gte = num_greater_eq (lhs, rhs, precision); | |
1381 | if (op == CPP_MIN) | |
1382 | gte = !gte; | |
1383 | if (!gte) | |
1384 | lhs = rhs; | |
1385 | lhs.unsignedp = unsignedp; | |
1386 | } | |
1387 | break; | |
1388 | ||
1389 | /* Arithmetic. */ | |
1390 | case CPP_MINUS: | |
1391 | rhs = num_negate (rhs, precision); | |
1392 | case CPP_PLUS: | |
1393 | result.low = lhs.low + rhs.low; | |
1394 | result.high = lhs.high + rhs.high; | |
1395 | if (result.low < lhs.low) | |
1396 | result.high++; | |
1397 | ||
1398 | result = num_trim (result, precision); | |
1399 | result.unsignedp = lhs.unsignedp || rhs.unsignedp; | |
1400 | if (result.unsignedp) | |
1401 | result.overflow = false; | |
1402 | else | |
1403 | { | |
1404 | bool lhsp = num_positive (lhs, precision); | |
1405 | result.overflow = (lhsp == num_positive (rhs, precision) | |
1406 | && lhsp != num_positive (result, precision)); | |
1407 | } | |
1408 | return result; | |
1409 | ||
1410 | /* Comma. */ | |
1411 | default: /* case CPP_COMMA: */ | |
75aef48a | 1412 | if (CPP_PEDANTIC (pfile) && !pfile->state.skip_eval) |
91318908 NB |
1413 | cpp_error (pfile, DL_PEDWARN, |
1414 | "comma operator in operand of #if"); | |
1415 | lhs = rhs; | |
1416 | break; | |
1417 | } | |
1418 | ||
1419 | return lhs; | |
1420 | } | |
1421 | ||
1422 | /* Multiplies two unsigned cpp_num_parts to give a cpp_num. This | |
1423 | cannot overflow. */ | |
1424 | static cpp_num | |
1425 | num_part_mul (lhs, rhs) | |
1426 | cpp_num_part lhs, rhs; | |
1427 | { | |
1428 | cpp_num result; | |
1429 | cpp_num_part middle[2], temp; | |
1430 | ||
1431 | result.low = LOW_PART (lhs) * LOW_PART (rhs); | |
1432 | result.high = HIGH_PART (lhs) * HIGH_PART (rhs); | |
1433 | ||
1434 | middle[0] = LOW_PART (lhs) * HIGH_PART (rhs); | |
1435 | middle[1] = HIGH_PART (lhs) * LOW_PART (rhs); | |
1436 | ||
1437 | temp = result.low; | |
1438 | result.low += LOW_PART (middle[0]) << (PART_PRECISION / 2); | |
1439 | if (result.low < temp) | |
1440 | result.high++; | |
1441 | ||
1442 | temp = result.low; | |
1443 | result.low += LOW_PART (middle[1]) << (PART_PRECISION / 2); | |
1444 | if (result.low < temp) | |
1445 | result.high++; | |
1446 | ||
1447 | result.high += HIGH_PART (middle[0]); | |
1448 | result.high += HIGH_PART (middle[1]); | |
1449 | ||
1450 | return result; | |
1451 | } | |
1452 | ||
1453 | /* Multiply two preprocessing numbers. */ | |
1454 | static cpp_num | |
ad28cff7 | 1455 | num_mul (pfile, lhs, rhs) |
91318908 NB |
1456 | cpp_reader *pfile; |
1457 | cpp_num lhs, rhs; | |
91318908 NB |
1458 | { |
1459 | cpp_num result, temp; | |
1460 | bool unsignedp = lhs.unsignedp || rhs.unsignedp; | |
1461 | bool overflow, negate = false; | |
1462 | size_t precision = CPP_OPTION (pfile, precision); | |
1463 | ||
1464 | /* Prepare for unsigned multiplication. */ | |
1465 | if (!unsignedp) | |
1466 | { | |
1467 | if (!num_positive (lhs, precision)) | |
1468 | negate = !negate, lhs = num_negate (lhs, precision); | |
1469 | if (!num_positive (rhs, precision)) | |
1470 | negate = !negate, rhs = num_negate (rhs, precision); | |
1471 | } | |
1472 | ||
1473 | overflow = lhs.high && rhs.high; | |
1474 | result = num_part_mul (lhs.low, rhs.low); | |
1475 | ||
1476 | temp = num_part_mul (lhs.high, rhs.low); | |
1477 | result.high += temp.low; | |
1478 | if (temp.high) | |
1479 | overflow = true; | |
1480 | ||
1481 | temp = num_part_mul (lhs.low, rhs.high); | |
1482 | result.high += temp.low; | |
1483 | if (temp.high) | |
1484 | overflow = true; | |
1485 | ||
1486 | temp.low = result.low, temp.high = result.high; | |
1487 | result = num_trim (result, precision); | |
1488 | if (!num_eq (result, temp)) | |
1489 | overflow = true; | |
1490 | ||
1491 | if (negate) | |
1492 | result = num_negate (result, precision); | |
1493 | ||
1494 | if (unsignedp) | |
1495 | result.overflow = false; | |
1496 | else | |
1497 | result.overflow = overflow || (num_positive (result, precision) ^ !negate | |
1498 | && !num_zerop (result)); | |
1499 | result.unsignedp = unsignedp; | |
1500 | ||
1501 | return result; | |
1502 | } | |
1503 | ||
1504 | /* Divide two preprocessing numbers, returning the answer or the | |
1505 | remainder depending upon OP. */ | |
1506 | static cpp_num | |
1507 | num_div_op (pfile, lhs, rhs, op) | |
1508 | cpp_reader *pfile; | |
1509 | cpp_num lhs, rhs; | |
1510 | enum cpp_ttype op; | |
1511 | { | |
1512 | cpp_num result, sub; | |
1513 | cpp_num_part mask; | |
1514 | bool unsignedp = lhs.unsignedp || rhs.unsignedp; | |
1515 | bool negate = false, lhs_neg = false; | |
1516 | size_t i, precision = CPP_OPTION (pfile, precision); | |
1517 | ||
1518 | /* Prepare for unsigned division. */ | |
1519 | if (!unsignedp) | |
1520 | { | |
1521 | if (!num_positive (lhs, precision)) | |
1522 | negate = !negate, lhs_neg = true, lhs = num_negate (lhs, precision); | |
1523 | if (!num_positive (rhs, precision)) | |
1524 | negate = !negate, rhs = num_negate (rhs, precision); | |
1525 | } | |
1526 | ||
1527 | /* Find the high bit. */ | |
1528 | if (rhs.high) | |
1529 | { | |
1530 | i = precision - 1; | |
359b0bec | 1531 | mask = (cpp_num_part) 1 << (i - PART_PRECISION); |
91318908 NB |
1532 | for (; ; i--, mask >>= 1) |
1533 | if (rhs.high & mask) | |
1534 | break; | |
1535 | } | |
1536 | else if (rhs.low) | |
1537 | { | |
1538 | if (precision > PART_PRECISION) | |
1539 | i = precision - PART_PRECISION - 1; | |
1540 | else | |
1541 | i = precision - 1; | |
359b0bec | 1542 | mask = (cpp_num_part) 1 << i; |
91318908 NB |
1543 | for (; ; i--, mask >>= 1) |
1544 | if (rhs.low & mask) | |
1545 | break; | |
1546 | } | |
1547 | else | |
1548 | { | |
75aef48a NB |
1549 | if (!pfile->state.skip_eval) |
1550 | cpp_error (pfile, DL_ERROR, "division by zero in #if"); | |
91318908 NB |
1551 | return lhs; |
1552 | } | |
1553 | ||
da7d8304 | 1554 | /* First nonzero bit of RHS is bit I. Do naive division by |
91318908 NB |
1555 | shifting the RHS fully left, and subtracting from LHS if LHS is |
1556 | at least as big, and then repeating but with one less shift. | |
1557 | This is not very efficient, but is easy to understand. */ | |
1558 | ||
1559 | rhs.unsignedp = true; | |
1560 | lhs.unsignedp = true; | |
1561 | i = precision - i - 1; | |
1562 | sub = num_lshift (rhs, precision, i); | |
1563 | ||
1564 | result.high = result.low = 0; | |
1565 | for (;;) | |
1566 | { | |
1567 | if (num_greater_eq (lhs, sub, precision)) | |
1568 | { | |
1569 | lhs = num_binary_op (pfile, lhs, sub, CPP_MINUS); | |
1570 | if (i >= PART_PRECISION) | |
359b0bec | 1571 | result.high |= (cpp_num_part) 1 << (i - PART_PRECISION); |
91318908 | 1572 | else |
359b0bec | 1573 | result.low |= (cpp_num_part) 1 << i; |
91318908 NB |
1574 | } |
1575 | if (i-- == 0) | |
1576 | break; | |
1577 | sub.low = (sub.low >> 1) | (sub.high << (PART_PRECISION - 1)); | |
1578 | sub.high >>= 1; | |
1579 | } | |
1580 | ||
1581 | /* We divide so that the remainder has the sign of the LHS. */ | |
1582 | if (op == CPP_DIV) | |
1583 | { | |
1584 | result.unsignedp = unsignedp; | |
1585 | if (unsignedp) | |
1586 | result.overflow = false; | |
1587 | else | |
1588 | { | |
1589 | if (negate) | |
1590 | result = num_negate (result, precision); | |
1591 | result.overflow = num_positive (result, precision) ^ !negate; | |
1592 | } | |
1593 | ||
1594 | return result; | |
1595 | } | |
1596 | ||
1597 | /* CPP_MOD. */ | |
1598 | lhs.unsignedp = unsignedp; | |
1599 | lhs.overflow = false; | |
1600 | if (lhs_neg) | |
1601 | lhs = num_negate (lhs, precision); | |
1602 | ||
1603 | return lhs; | |
1604 | } |