xref: /netbsd-src/external/gpl3/gcc.old/dist/libcpp/lex.c (revision 53d1339bf7f9c7367b35a9e1ebe693f9b047a47b)
1 /* CPP Library - lexical analysis.
2    Copyright (C) 2000-2019 Free Software Foundation, Inc.
3    Contributed by Per Bothner, 1994-95.
4    Based on CCCP program by Paul Rubin, June 1986
5    Adapted to ANSI C, Richard Stallman, Jan 1987
6    Broken out to separate file, Zack Weinberg, Mar 2000
7 
8 This program is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by the
10 Free Software Foundation; either version 3, or (at your option) any
11 later version.
12 
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 GNU General Public License for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with this program; see the file COPYING3.  If not see
20 <http://www.gnu.org/licenses/>.  */
21 
22 #include "config.h"
23 #include "system.h"
24 #include "cpplib.h"
25 #include "internal.h"
26 
27 enum spell_type
28 {
29   SPELL_OPERATOR = 0,
30   SPELL_IDENT,
31   SPELL_LITERAL,
32   SPELL_NONE
33 };
34 
35 struct token_spelling
36 {
37   enum spell_type category;
38   const unsigned char *name;
39 };
40 
41 static const unsigned char *const digraph_spellings[] =
42 { UC"%:", UC"%:%:", UC"<:", UC":>", UC"<%", UC"%>" };
43 
44 #define OP(e, s) { SPELL_OPERATOR, UC s  },
45 #define TK(e, s) { SPELL_ ## s,    UC #e },
46 static const struct token_spelling token_spellings[N_TTYPES] = { TTYPE_TABLE };
47 #undef OP
48 #undef TK
49 
50 #define TOKEN_SPELL(token) (token_spellings[(token)->type].category)
51 #define TOKEN_NAME(token) (token_spellings[(token)->type].name)
52 
53 static void add_line_note (cpp_buffer *, const uchar *, unsigned int);
54 static int skip_line_comment (cpp_reader *);
55 static void skip_whitespace (cpp_reader *, cppchar_t);
56 static void lex_string (cpp_reader *, cpp_token *, const uchar *);
57 static void save_comment (cpp_reader *, cpp_token *, const uchar *, cppchar_t);
58 static void store_comment (cpp_reader *, cpp_token *);
59 static void create_literal (cpp_reader *, cpp_token *, const uchar *,
60 			    unsigned int, enum cpp_ttype);
61 static bool warn_in_comment (cpp_reader *, _cpp_line_note *);
62 static int name_p (cpp_reader *, const cpp_string *);
63 static tokenrun *next_tokenrun (tokenrun *);
64 
65 static _cpp_buff *new_buff (size_t);
66 
67 
68 /* Utility routine:
69 
70    Compares, the token TOKEN to the NUL-terminated string STRING.
71    TOKEN must be a CPP_NAME.  Returns 1 for equal, 0 for unequal.  */
72 int
73 cpp_ideq (const cpp_token *token, const char *string)
74 {
75   if (token->type != CPP_NAME)
76     return 0;
77 
78   return !ustrcmp (NODE_NAME (token->val.node.node), (const uchar *) string);
79 }
80 
81 /* Record a note TYPE at byte POS into the current cleaned logical
82    line.  */
83 static void
84 add_line_note (cpp_buffer *buffer, const uchar *pos, unsigned int type)
85 {
86   if (buffer->notes_used == buffer->notes_cap)
87     {
88       buffer->notes_cap = buffer->notes_cap * 2 + 200;
89       buffer->notes = XRESIZEVEC (_cpp_line_note, buffer->notes,
90                                   buffer->notes_cap);
91     }
92 
93   buffer->notes[buffer->notes_used].pos = pos;
94   buffer->notes[buffer->notes_used].type = type;
95   buffer->notes_used++;
96 }
97 
98 
99 /* Fast path to find line special characters using optimized character
100    scanning algorithms.  Anything complicated falls back to the slow
101    path below.  Since this loop is very hot it's worth doing these kinds
102    of optimizations.
103 
104    One of the paths through the ifdefs should provide
105 
106      const uchar *search_line_fast (const uchar *s, const uchar *end);
107 
108    Between S and END, search for \n, \r, \\, ?.  Return a pointer to
109    the found character.
110 
111    Note that the last character of the buffer is *always* a newline,
112    as forced by _cpp_convert_input.  This fact can be used to avoid
113    explicitly looking for the end of the buffer.  */
114 
115 /* Configure gives us an ifdef test.  */
116 #ifndef WORDS_BIGENDIAN
117 #define WORDS_BIGENDIAN 0
118 #endif
119 
120 /* We'd like the largest integer that fits into a register.  There's nothing
121    in <stdint.h> that gives us that.  For most hosts this is unsigned long,
122    but MS decided on an LLP64 model.  Thankfully when building with GCC we
123    can get the "real" word size.  */
124 #ifdef __GNUC__
125 typedef unsigned int word_type __attribute__((__mode__(__word__)));
126 #else
127 typedef unsigned long word_type;
128 #endif
129 
130 /* The code below is only expecting sizes 4 or 8.
131    Die at compile-time if this expectation is violated.  */
132 typedef char check_word_type_size
133   [(sizeof(word_type) == 8 || sizeof(word_type) == 4) * 2 - 1];
134 
135 /* Return X with the first N bytes forced to values that won't match one
136    of the interesting characters.  Note that NUL is not interesting.  */
137 
138 static inline word_type
139 acc_char_mask_misalign (word_type val, unsigned int n)
140 {
141   word_type mask = -1;
142   if (WORDS_BIGENDIAN)
143     mask >>= n * 8;
144   else
145     mask <<= n * 8;
146   return val & mask;
147 }
148 
149 /* Return X replicated to all byte positions within WORD_TYPE.  */
150 
151 static inline word_type
152 acc_char_replicate (uchar x)
153 {
154   word_type ret;
155 
156   ret = (x << 24) | (x << 16) | (x << 8) | x;
157   if (sizeof(word_type) == 8)
158     ret = (ret << 16 << 16) | ret;
159   return ret;
160 }
161 
162 /* Return non-zero if some byte of VAL is (probably) C.  */
163 
164 static inline word_type
165 acc_char_cmp (word_type val, word_type c)
166 {
167 #if defined(__GNUC__) && defined(__alpha__)
168   /* We can get exact results using a compare-bytes instruction.
169      Get (val == c) via (0 >= (val ^ c)).  */
170   return __builtin_alpha_cmpbge (0, val ^ c);
171 #else
172   word_type magic = 0x7efefefeU;
173   if (sizeof(word_type) == 8)
174     magic = (magic << 16 << 16) | 0xfefefefeU;
175   magic |= 1;
176 
177   val ^= c;
178   return ((val + magic) ^ ~val) & ~magic;
179 #endif
180 }
181 
182 /* Given the result of acc_char_cmp is non-zero, return the index of
183    the found character.  If this was a false positive, return -1.  */
184 
185 static inline int
186 acc_char_index (word_type cmp ATTRIBUTE_UNUSED,
187 		word_type val ATTRIBUTE_UNUSED)
188 {
189 #if defined(__GNUC__) && defined(__alpha__) && !WORDS_BIGENDIAN
190   /* The cmpbge instruction sets *bits* of the result corresponding to
191      matches in the bytes with no false positives.  */
192   return __builtin_ctzl (cmp);
193 #else
194   unsigned int i;
195 
196   /* ??? It would be nice to force unrolling here,
197      and have all of these constants folded.  */
198   for (i = 0; i < sizeof(word_type); ++i)
199     {
200       uchar c;
201       if (WORDS_BIGENDIAN)
202 	c = (val >> (sizeof(word_type) - i - 1) * 8) & 0xff;
203       else
204 	c = (val >> i * 8) & 0xff;
205 
206       if (c == '\n' || c == '\r' || c == '\\' || c == '?')
207 	return i;
208     }
209 
210   return -1;
211 #endif
212 }
213 
214 /* A version of the fast scanner using bit fiddling techniques.
215 
216    For 32-bit words, one would normally perform 16 comparisons and
217    16 branches.  With this algorithm one performs 24 arithmetic
218    operations and one branch.  Whether this is faster with a 32-bit
219    word size is going to be somewhat system dependent.
220 
221    For 64-bit words, we eliminate twice the number of comparisons
222    and branches without increasing the number of arithmetic operations.
223    It's almost certainly going to be a win with 64-bit word size.  */
224 
225 static const uchar * search_line_acc_char (const uchar *, const uchar *)
226   ATTRIBUTE_UNUSED;
227 
228 static const uchar *
229 search_line_acc_char (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
230 {
231   const word_type repl_nl = acc_char_replicate ('\n');
232   const word_type repl_cr = acc_char_replicate ('\r');
233   const word_type repl_bs = acc_char_replicate ('\\');
234   const word_type repl_qm = acc_char_replicate ('?');
235 
236   unsigned int misalign;
237   const word_type *p;
238   word_type val, t;
239 
240   /* Align the buffer.  Mask out any bytes from before the beginning.  */
241   p = (word_type *)((uintptr_t)s & -sizeof(word_type));
242   val = *p;
243   misalign = (uintptr_t)s & (sizeof(word_type) - 1);
244   if (misalign)
245     val = acc_char_mask_misalign (val, misalign);
246 
247   /* Main loop.  */
248   while (1)
249     {
250       t  = acc_char_cmp (val, repl_nl);
251       t |= acc_char_cmp (val, repl_cr);
252       t |= acc_char_cmp (val, repl_bs);
253       t |= acc_char_cmp (val, repl_qm);
254 
255       if (__builtin_expect (t != 0, 0))
256 	{
257 	  int i = acc_char_index (t, val);
258 	  if (i >= 0)
259 	    return (const uchar *)p + i;
260 	}
261 
262       val = *++p;
263     }
264 }
265 
266 /* Disable on Solaris 2/x86 until the following problem can be properly
267    autoconfed:
268 
269    The Solaris 10+ assembler tags objects with the instruction set
270    extensions used, so SSE4.2 executables cannot run on machines that
271    don't support that extension.  */
272 
273 #if (GCC_VERSION >= 4005) && (__GNUC__ >= 5 || !defined(__PIC__)) && (defined(__i386__) || defined(__x86_64__)) && !(defined(__sun__) && defined(__svr4__))
274 
275 /* Replicated character data to be shared between implementations.
276    Recall that outside of a context with vector support we can't
277    define compatible vector types, therefore these are all defined
278    in terms of raw characters.  */
279 static const char repl_chars[4][16] __attribute__((aligned(16))) = {
280   { '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n',
281     '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n' },
282   { '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r',
283     '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r' },
284   { '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\',
285     '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\' },
286   { '?', '?', '?', '?', '?', '?', '?', '?',
287     '?', '?', '?', '?', '?', '?', '?', '?' },
288 };
289 
290 /* A version of the fast scanner using MMX vectorized byte compare insns.
291 
292    This uses the PMOVMSKB instruction which was introduced with "MMX2",
293    which was packaged into SSE1; it is also present in the AMD MMX
294    extension.  Mark the function as using "sse" so that we emit a real
295    "emms" instruction, rather than the 3dNOW "femms" instruction.  */
296 
297 static const uchar *
298 #ifndef __SSE__
299 __attribute__((__target__("sse")))
300 #endif
301 search_line_mmx (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
302 {
303   typedef char v8qi __attribute__ ((__vector_size__ (8)));
304   typedef int __m64 __attribute__ ((__vector_size__ (8), __may_alias__));
305 
306   const v8qi repl_nl = *(const v8qi *)repl_chars[0];
307   const v8qi repl_cr = *(const v8qi *)repl_chars[1];
308   const v8qi repl_bs = *(const v8qi *)repl_chars[2];
309   const v8qi repl_qm = *(const v8qi *)repl_chars[3];
310 
311   unsigned int misalign, found, mask;
312   const v8qi *p;
313   v8qi data, t, c;
314 
315   /* Align the source pointer.  While MMX doesn't generate unaligned data
316      faults, this allows us to safely scan to the end of the buffer without
317      reading beyond the end of the last page.  */
318   misalign = (uintptr_t)s & 7;
319   p = (const v8qi *)((uintptr_t)s & -8);
320   data = *p;
321 
322   /* Create a mask for the bytes that are valid within the first
323      16-byte block.  The Idea here is that the AND with the mask
324      within the loop is "free", since we need some AND or TEST
325      insn in order to set the flags for the branch anyway.  */
326   mask = -1u << misalign;
327 
328   /* Main loop processing 8 bytes at a time.  */
329   goto start;
330   do
331     {
332       data = *++p;
333       mask = -1;
334 
335     start:
336       t = __builtin_ia32_pcmpeqb(data, repl_nl);
337       c = __builtin_ia32_pcmpeqb(data, repl_cr);
338       t = (v8qi) __builtin_ia32_por ((__m64)t, (__m64)c);
339       c = __builtin_ia32_pcmpeqb(data, repl_bs);
340       t = (v8qi) __builtin_ia32_por ((__m64)t, (__m64)c);
341       c = __builtin_ia32_pcmpeqb(data, repl_qm);
342       t = (v8qi) __builtin_ia32_por ((__m64)t, (__m64)c);
343       found = __builtin_ia32_pmovmskb (t);
344       found &= mask;
345     }
346   while (!found);
347 
348   __builtin_ia32_emms ();
349 
350   /* FOUND contains 1 in bits for which we matched a relevant
351      character.  Conversion to the byte index is trivial.  */
352   found = __builtin_ctz(found);
353   return (const uchar *)p + found;
354 }
355 
356 /* A version of the fast scanner using SSE2 vectorized byte compare insns.  */
357 
358 static const uchar *
359 #ifndef __SSE2__
360 __attribute__((__target__("sse2")))
361 #endif
362 search_line_sse2 (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
363 {
364   typedef char v16qi __attribute__ ((__vector_size__ (16)));
365 
366   const v16qi repl_nl = *(const v16qi *)repl_chars[0];
367   const v16qi repl_cr = *(const v16qi *)repl_chars[1];
368   const v16qi repl_bs = *(const v16qi *)repl_chars[2];
369   const v16qi repl_qm = *(const v16qi *)repl_chars[3];
370 
371   unsigned int misalign, found, mask;
372   const v16qi *p;
373   v16qi data, t;
374 
375   /* Align the source pointer.  */
376   misalign = (uintptr_t)s & 15;
377   p = (const v16qi *)((uintptr_t)s & -16);
378   data = *p;
379 
380   /* Create a mask for the bytes that are valid within the first
381      16-byte block.  The Idea here is that the AND with the mask
382      within the loop is "free", since we need some AND or TEST
383      insn in order to set the flags for the branch anyway.  */
384   mask = -1u << misalign;
385 
386   /* Main loop processing 16 bytes at a time.  */
387   goto start;
388   do
389     {
390       data = *++p;
391       mask = -1;
392 
393     start:
394       t  = __builtin_ia32_pcmpeqb128(data, repl_nl);
395       t |= __builtin_ia32_pcmpeqb128(data, repl_cr);
396       t |= __builtin_ia32_pcmpeqb128(data, repl_bs);
397       t |= __builtin_ia32_pcmpeqb128(data, repl_qm);
398       found = __builtin_ia32_pmovmskb128 (t);
399       found &= mask;
400     }
401   while (!found);
402 
403   /* FOUND contains 1 in bits for which we matched a relevant
404      character.  Conversion to the byte index is trivial.  */
405   found = __builtin_ctz(found);
406   return (const uchar *)p + found;
407 }
408 
409 #ifdef HAVE_SSE4
410 /* A version of the fast scanner using SSE 4.2 vectorized string insns.  */
411 
412 static const uchar *
413 #ifndef __SSE4_2__
414 __attribute__((__target__("sse4.2")))
415 #endif
416 search_line_sse42 (const uchar *s, const uchar *end)
417 {
418   typedef char v16qi __attribute__ ((__vector_size__ (16)));
419   static const v16qi search = { '\n', '\r', '?', '\\' };
420 
421   uintptr_t si = (uintptr_t)s;
422   uintptr_t index;
423 
424   /* Check for unaligned input.  */
425   if (si & 15)
426     {
427       v16qi sv;
428 
429       if (__builtin_expect (end - s < 16, 0)
430 	  && __builtin_expect ((si & 0xfff) > 0xff0, 0))
431 	{
432 	  /* There are less than 16 bytes left in the buffer, and less
433 	     than 16 bytes left on the page.  Reading 16 bytes at this
434 	     point might generate a spurious page fault.  Defer to the
435 	     SSE2 implementation, which already handles alignment.  */
436 	  return search_line_sse2 (s, end);
437 	}
438 
439       /* ??? The builtin doesn't understand that the PCMPESTRI read from
440 	 memory need not be aligned.  */
441       sv = __builtin_ia32_loaddqu ((const char *) s);
442       index = __builtin_ia32_pcmpestri128 (search, 4, sv, 16, 0);
443 
444       if (__builtin_expect (index < 16, 0))
445 	goto found;
446 
447       /* Advance the pointer to an aligned address.  We will re-scan a
448 	 few bytes, but we no longer need care for reading past the
449 	 end of a page, since we're guaranteed a match.  */
450       s = (const uchar *)((si + 15) & -16);
451     }
452 
453   /* Main loop, processing 16 bytes at a time.  */
454 #ifdef __GCC_ASM_FLAG_OUTPUTS__
455   while (1)
456     {
457       char f;
458 
459       /* By using inline assembly instead of the builtin,
460 	 we can use the result, as well as the flags set.  */
461       __asm ("%vpcmpestri\t$0, %2, %3"
462 	     : "=c"(index), "=@ccc"(f)
463 	     : "m"(*s), "x"(search), "a"(4), "d"(16));
464       if (f)
465 	break;
466 
467       s += 16;
468     }
469 #else
470   s -= 16;
471   /* By doing the whole loop in inline assembly,
472      we can make proper use of the flags set.  */
473   __asm (      ".balign 16\n"
474 	"0:	add $16, %1\n"
475 	"	%vpcmpestri\t$0, (%1), %2\n"
476 	"	jnc 0b"
477 	: "=&c"(index), "+r"(s)
478 	: "x"(search), "a"(4), "d"(16));
479 #endif
480 
481  found:
482   return s + index;
483 }
484 
485 #else
486 /* Work around out-dated assemblers without sse4 support.  */
487 #define search_line_sse42 search_line_sse2
488 #endif
489 
490 /* Check the CPU capabilities.  */
491 
492 #include "../gcc/config/i386/cpuid.h"
493 
494 typedef const uchar * (*search_line_fast_type) (const uchar *, const uchar *);
495 static search_line_fast_type search_line_fast;
496 
497 #define HAVE_init_vectorized_lexer 1
498 static inline void
499 init_vectorized_lexer (void)
500 {
501   unsigned dummy, ecx = 0, edx = 0;
502   search_line_fast_type impl = search_line_acc_char;
503   int minimum = 0;
504 
505 #if defined(__SSE4_2__)
506   minimum = 3;
507 #elif defined(__SSE2__)
508   minimum = 2;
509 #elif defined(__SSE__)
510   minimum = 1;
511 #endif
512 
513   if (minimum == 3)
514     impl = search_line_sse42;
515   else if (__get_cpuid (1, &dummy, &dummy, &ecx, &edx) || minimum == 2)
516     {
517       if (minimum == 3 || (ecx & bit_SSE4_2))
518         impl = search_line_sse42;
519       else if (minimum == 2 || (edx & bit_SSE2))
520 	impl = search_line_sse2;
521       else if (minimum == 1 || (edx & bit_SSE))
522 	impl = search_line_mmx;
523     }
524   else if (__get_cpuid (0x80000001, &dummy, &dummy, &dummy, &edx))
525     {
526       if (minimum == 1
527 	  || (edx & (bit_MMXEXT | bit_CMOV)) == (bit_MMXEXT | bit_CMOV))
528 	impl = search_line_mmx;
529     }
530 
531   search_line_fast = impl;
532 }
533 
534 #elif defined(_ARCH_PWR8) && defined(__ALTIVEC__)
535 
536 /* A vection of the fast scanner using AltiVec vectorized byte compares
537    and VSX unaligned loads (when VSX is available).  This is otherwise
538    the same as the pre-GCC 5 version.  */
539 
540 ATTRIBUTE_NO_SANITIZE_UNDEFINED
541 static const uchar *
542 search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
543 {
544   typedef __attribute__((altivec(vector))) unsigned char vc;
545 
546   const vc repl_nl = {
547     '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n',
548     '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n'
549   };
550   const vc repl_cr = {
551     '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r',
552     '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r'
553   };
554   const vc repl_bs = {
555     '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\',
556     '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\'
557   };
558   const vc repl_qm = {
559     '?', '?', '?', '?', '?', '?', '?', '?',
560     '?', '?', '?', '?', '?', '?', '?', '?',
561   };
562   const vc zero = { 0 };
563 
564   vc data, t;
565 
566   /* Main loop processing 16 bytes at a time.  */
567   do
568     {
569       vc m_nl, m_cr, m_bs, m_qm;
570 
571       data = __builtin_vec_vsx_ld (0, s);
572       s += 16;
573 
574       m_nl = (vc) __builtin_vec_cmpeq(data, repl_nl);
575       m_cr = (vc) __builtin_vec_cmpeq(data, repl_cr);
576       m_bs = (vc) __builtin_vec_cmpeq(data, repl_bs);
577       m_qm = (vc) __builtin_vec_cmpeq(data, repl_qm);
578       t = (m_nl | m_cr) | (m_bs | m_qm);
579 
580       /* T now contains 0xff in bytes for which we matched one of the relevant
581 	 characters.  We want to exit the loop if any byte in T is non-zero.
582 	 Below is the expansion of vec_any_ne(t, zero).  */
583     }
584   while (!__builtin_vec_vcmpeq_p(/*__CR6_LT_REV*/3, t, zero));
585 
586   /* Restore s to to point to the 16 bytes we just processed.  */
587   s -= 16;
588 
589   {
590 #define N  (sizeof(vc) / sizeof(long))
591 
592     union {
593       vc v;
594       /* Statically assert that N is 2 or 4.  */
595       unsigned long l[(N == 2 || N == 4) ? N : -1];
596     } u;
597     unsigned long l, i = 0;
598 
599     u.v = t;
600 
601     /* Find the first word of T that is non-zero.  */
602     switch (N)
603       {
604       case 4:
605 	l = u.l[i++];
606 	if (l != 0)
607 	  break;
608 	s += sizeof(unsigned long);
609 	l = u.l[i++];
610 	if (l != 0)
611 	  break;
612 	s += sizeof(unsigned long);
613 	/* FALLTHRU */
614       case 2:
615 	l = u.l[i++];
616 	if (l != 0)
617 	  break;
618 	s += sizeof(unsigned long);
619 	l = u.l[i];
620       }
621 
622     /* L now contains 0xff in bytes for which we matched one of the
623        relevant characters.  We can find the byte index by finding
624        its bit index and dividing by 8.  */
625 #ifdef __BIG_ENDIAN__
626     l = __builtin_clzl(l) >> 3;
627 #else
628     l = __builtin_ctzl(l) >> 3;
629 #endif
630     return s + l;
631 
632 #undef N
633   }
634 }
635 
636 #elif (GCC_VERSION >= 4005) && defined(__ALTIVEC__) && defined (__BIG_ENDIAN__)
637 
638 /* A vection of the fast scanner using AltiVec vectorized byte compares.
639    This cannot be used for little endian because vec_lvsl/lvsr are
640    deprecated for little endian and the code won't work properly.  */
641 /* ??? Unfortunately, attribute(target("altivec")) is not yet supported,
642    so we can't compile this function without -maltivec on the command line
643    (or implied by some other switch).  */
644 
645 static const uchar *
646 search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
647 {
648   typedef __attribute__((altivec(vector))) unsigned char vc;
649 
650   const vc repl_nl = {
651     '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n',
652     '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n'
653   };
654   const vc repl_cr = {
655     '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r',
656     '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r'
657   };
658   const vc repl_bs = {
659     '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\',
660     '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\'
661   };
662   const vc repl_qm = {
663     '?', '?', '?', '?', '?', '?', '?', '?',
664     '?', '?', '?', '?', '?', '?', '?', '?',
665   };
666   const vc ones = {
667     -1, -1, -1, -1, -1, -1, -1, -1,
668     -1, -1, -1, -1, -1, -1, -1, -1,
669   };
670   const vc zero = { 0 };
671 
672   vc data, mask, t;
673 
674   /* Altivec loads automatically mask addresses with -16.  This lets us
675      issue the first load as early as possible.  */
676   data = __builtin_vec_ld(0, (const vc *)s);
677 
678   /* Discard bytes before the beginning of the buffer.  Do this by
679      beginning with all ones and shifting in zeros according to the
680      mis-alignment.  The LVSR instruction pulls the exact shift we
681      want from the address.  */
682   mask = __builtin_vec_lvsr(0, s);
683   mask = __builtin_vec_perm(zero, ones, mask);
684   data &= mask;
685 
686   /* While altivec loads mask addresses, we still need to align S so
687      that the offset we compute at the end is correct.  */
688   s = (const uchar *)((uintptr_t)s & -16);
689 
690   /* Main loop processing 16 bytes at a time.  */
691   goto start;
692   do
693     {
694       vc m_nl, m_cr, m_bs, m_qm;
695 
696       s += 16;
697       data = __builtin_vec_ld(0, (const vc *)s);
698 
699     start:
700       m_nl = (vc) __builtin_vec_cmpeq(data, repl_nl);
701       m_cr = (vc) __builtin_vec_cmpeq(data, repl_cr);
702       m_bs = (vc) __builtin_vec_cmpeq(data, repl_bs);
703       m_qm = (vc) __builtin_vec_cmpeq(data, repl_qm);
704       t = (m_nl | m_cr) | (m_bs | m_qm);
705 
706       /* T now contains 0xff in bytes for which we matched one of the relevant
707 	 characters.  We want to exit the loop if any byte in T is non-zero.
708 	 Below is the expansion of vec_any_ne(t, zero).  */
709     }
710   while (!__builtin_vec_vcmpeq_p(/*__CR6_LT_REV*/3, t, zero));
711 
712   {
713 #define N  (sizeof(vc) / sizeof(long))
714 
715     union {
716       vc v;
717       /* Statically assert that N is 2 or 4.  */
718       unsigned long l[(N == 2 || N == 4) ? N : -1];
719     } u;
720     unsigned long l, i = 0;
721 
722     u.v = t;
723 
724     /* Find the first word of T that is non-zero.  */
725     switch (N)
726       {
727       case 4:
728 	l = u.l[i++];
729 	if (l != 0)
730 	  break;
731 	s += sizeof(unsigned long);
732 	l = u.l[i++];
733 	if (l != 0)
734 	  break;
735 	s += sizeof(unsigned long);
736 	/* FALLTHROUGH */
737       case 2:
738 	l = u.l[i++];
739 	if (l != 0)
740 	  break;
741 	s += sizeof(unsigned long);
742 	l = u.l[i];
743       }
744 
745     /* L now contains 0xff in bytes for which we matched one of the
746        relevant characters.  We can find the byte index by finding
747        its bit index and dividing by 8.  */
748     l = __builtin_clzl(l) >> 3;
749     return s + l;
750 
751 #undef N
752   }
753 }
754 
755 #elif defined (__ARM_NEON) && defined (__ARM_64BIT_STATE)
756 #include "arm_neon.h"
757 
758 /* This doesn't have to be the exact page size, but no system may use
759    a size smaller than this.  ARMv8 requires a minimum page size of
760    4k.  The impact of being conservative here is a small number of
761    cases will take the slightly slower entry path into the main
762    loop.  */
763 
764 #define AARCH64_MIN_PAGE_SIZE 4096
765 
766 static const uchar *
767 search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
768 {
769   const uint8x16_t repl_nl = vdupq_n_u8 ('\n');
770   const uint8x16_t repl_cr = vdupq_n_u8 ('\r');
771   const uint8x16_t repl_bs = vdupq_n_u8 ('\\');
772   const uint8x16_t repl_qm = vdupq_n_u8 ('?');
773   const uint8x16_t xmask = (uint8x16_t) vdupq_n_u64 (0x8040201008040201ULL);
774 
775 #ifdef __ARM_BIG_ENDIAN
776   const int16x8_t shift = {8, 8, 8, 8, 0, 0, 0, 0};
777 #else
778   const int16x8_t shift = {0, 0, 0, 0, 8, 8, 8, 8};
779 #endif
780 
781   unsigned int found;
782   const uint8_t *p;
783   uint8x16_t data;
784   uint8x16_t t;
785   uint16x8_t m;
786   uint8x16_t u, v, w;
787 
788   /* Align the source pointer.  */
789   p = (const uint8_t *)((uintptr_t)s & -16);
790 
791   /* Assuming random string start positions, with a 4k page size we'll take
792      the slow path about 0.37% of the time.  */
793   if (__builtin_expect ((AARCH64_MIN_PAGE_SIZE
794 			 - (((uintptr_t) s) & (AARCH64_MIN_PAGE_SIZE - 1)))
795 			< 16, 0))
796     {
797       /* Slow path: the string starts near a possible page boundary.  */
798       uint32_t misalign, mask;
799 
800       misalign = (uintptr_t)s & 15;
801       mask = (-1u << misalign) & 0xffff;
802       data = vld1q_u8 (p);
803       t = vceqq_u8 (data, repl_nl);
804       u = vceqq_u8 (data, repl_cr);
805       v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
806       w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
807       t = vorrq_u8 (v, w);
808       t = vandq_u8 (t, xmask);
809       m = vpaddlq_u8 (t);
810       m = vshlq_u16 (m, shift);
811       found = vaddvq_u16 (m);
812       found &= mask;
813       if (found)
814 	return (const uchar*)p + __builtin_ctz (found);
815     }
816   else
817     {
818       data = vld1q_u8 ((const uint8_t *) s);
819       t = vceqq_u8 (data, repl_nl);
820       u = vceqq_u8 (data, repl_cr);
821       v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
822       w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
823       t = vorrq_u8 (v, w);
824       if (__builtin_expect (vpaddd_u64 ((uint64x2_t)t) != 0, 0))
825 	goto done;
826     }
827 
828   do
829     {
830       p += 16;
831       data = vld1q_u8 (p);
832       t = vceqq_u8 (data, repl_nl);
833       u = vceqq_u8 (data, repl_cr);
834       v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
835       w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
836       t = vorrq_u8 (v, w);
837     } while (!vpaddd_u64 ((uint64x2_t)t));
838 
839 done:
840   /* Now that we've found the terminating substring, work out precisely where
841      we need to stop.  */
842   t = vandq_u8 (t, xmask);
843   m = vpaddlq_u8 (t);
844   m = vshlq_u16 (m, shift);
845   found = vaddvq_u16 (m);
846   return (((((uintptr_t) p) < (uintptr_t) s) ? s : (const uchar *)p)
847 	  + __builtin_ctz (found));
848 }
849 
850 #elif defined (__ARM_NEON)
851 #include "arm_neon.h"
852 
853 static const uchar *
854 search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
855 {
856   const uint8x16_t repl_nl = vdupq_n_u8 ('\n');
857   const uint8x16_t repl_cr = vdupq_n_u8 ('\r');
858   const uint8x16_t repl_bs = vdupq_n_u8 ('\\');
859   const uint8x16_t repl_qm = vdupq_n_u8 ('?');
860   const uint8x16_t xmask = (uint8x16_t) vdupq_n_u64 (0x8040201008040201ULL);
861 
862   unsigned int misalign, found, mask;
863   const uint8_t *p;
864   uint8x16_t data;
865 
866   /* Align the source pointer.  */
867   misalign = (uintptr_t)s & 15;
868   p = (const uint8_t *)((uintptr_t)s & -16);
869   data = vld1q_u8 (p);
870 
871   /* Create a mask for the bytes that are valid within the first
872      16-byte block.  The Idea here is that the AND with the mask
873      within the loop is "free", since we need some AND or TEST
874      insn in order to set the flags for the branch anyway.  */
875   mask = (-1u << misalign) & 0xffff;
876 
877   /* Main loop, processing 16 bytes at a time.  */
878   goto start;
879 
880   do
881     {
882       uint8x8_t l;
883       uint16x4_t m;
884       uint32x2_t n;
885       uint8x16_t t, u, v, w;
886 
887       p += 16;
888       data = vld1q_u8 (p);
889       mask = 0xffff;
890 
891     start:
892       t = vceqq_u8 (data, repl_nl);
893       u = vceqq_u8 (data, repl_cr);
894       v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
895       w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
896       t = vandq_u8 (vorrq_u8 (v, w), xmask);
897       l = vpadd_u8 (vget_low_u8 (t), vget_high_u8 (t));
898       m = vpaddl_u8 (l);
899       n = vpaddl_u16 (m);
900 
901       found = vget_lane_u32 ((uint32x2_t) vorr_u64 ((uint64x1_t) n,
902 	      vshr_n_u64 ((uint64x1_t) n, 24)), 0);
903       found &= mask;
904     }
905   while (!found);
906 
907   /* FOUND contains 1 in bits for which we matched a relevant
908      character.  Conversion to the byte index is trivial.  */
909   found = __builtin_ctz (found);
910   return (const uchar *)p + found;
911 }
912 
913 #else
914 
915 /* We only have one accelerated alternative.  Use a direct call so that
916    we encourage inlining.  */
917 
918 #define search_line_fast  search_line_acc_char
919 
920 #endif
921 
922 /* Initialize the lexer if needed.  */
923 
924 void
925 _cpp_init_lexer (void)
926 {
927 #ifdef HAVE_init_vectorized_lexer
928   init_vectorized_lexer ();
929 #endif
930 }
931 
932 /* Returns with a logical line that contains no escaped newlines or
933    trigraphs.  This is a time-critical inner loop.  */
934 void
935 _cpp_clean_line (cpp_reader *pfile)
936 {
937   cpp_buffer *buffer;
938   const uchar *s;
939   uchar c, *d, *p;
940 
941   buffer = pfile->buffer;
942   buffer->cur_note = buffer->notes_used = 0;
943   buffer->cur = buffer->line_base = buffer->next_line;
944   buffer->need_line = false;
945   s = buffer->next_line;
946 
947   if (!buffer->from_stage3)
948     {
949       const uchar *pbackslash = NULL;
950 
951       /* Fast path.  This is the common case of an un-escaped line with
952 	 no trigraphs.  The primary win here is by not writing any
953 	 data back to memory until we have to.  */
954       while (1)
955 	{
956 	  /* Perform an optimized search for \n, \r, \\, ?.  */
957 	  s = search_line_fast (s, buffer->rlimit);
958 
959 	  c = *s;
960 	  if (c == '\\')
961 	    {
962 	      /* Record the location of the backslash and continue.  */
963 	      pbackslash = s++;
964 	    }
965 	  else if (__builtin_expect (c == '?', 0))
966 	    {
967 	      if (__builtin_expect (s[1] == '?', false)
968 		   && _cpp_trigraph_map[s[2]])
969 		{
970 		  /* Have a trigraph.  We may or may not have to convert
971 		     it.  Add a line note regardless, for -Wtrigraphs.  */
972 		  add_line_note (buffer, s, s[2]);
973 		  if (CPP_OPTION (pfile, trigraphs))
974 		    {
975 		      /* We do, and that means we have to switch to the
976 		         slow path.  */
977 		      d = (uchar *) s;
978 		      *d = _cpp_trigraph_map[s[2]];
979 		      s += 2;
980 		      goto slow_path;
981 		    }
982 		}
983 	      /* Not a trigraph.  Continue on fast-path.  */
984 	      s++;
985 	    }
986 	  else
987 	    break;
988 	}
989 
990       /* This must be \r or \n.  We're either done, or we'll be forced
991 	 to write back to the buffer and continue on the slow path.  */
992       d = (uchar *) s;
993 
994       if (__builtin_expect (s == buffer->rlimit, false))
995 	goto done;
996 
997       /* DOS line ending? */
998       if (__builtin_expect (c == '\r', false) && s[1] == '\n')
999 	{
1000 	  s++;
1001 	  if (s == buffer->rlimit)
1002 	    goto done;
1003 	}
1004 
1005       if (__builtin_expect (pbackslash == NULL, true))
1006 	goto done;
1007 
1008       /* Check for escaped newline.  */
1009       p = d;
1010       while (is_nvspace (p[-1]))
1011 	p--;
1012       if (p - 1 != pbackslash)
1013 	goto done;
1014 
1015       /* Have an escaped newline; process it and proceed to
1016 	 the slow path.  */
1017       add_line_note (buffer, p - 1, p != d ? ' ' : '\\');
1018       d = p - 2;
1019       buffer->next_line = p - 1;
1020 
1021     slow_path:
1022       while (1)
1023 	{
1024 	  c = *++s;
1025 	  *++d = c;
1026 
1027 	  if (c == '\n' || c == '\r')
1028 	    {
1029 	      /* Handle DOS line endings.  */
1030 	      if (c == '\r' && s != buffer->rlimit && s[1] == '\n')
1031 		s++;
1032 	      if (s == buffer->rlimit)
1033 		break;
1034 
1035 	      /* Escaped?  */
1036 	      p = d;
1037 	      while (p != buffer->next_line && is_nvspace (p[-1]))
1038 		p--;
1039 	      if (p == buffer->next_line || p[-1] != '\\')
1040 		break;
1041 
1042 	      add_line_note (buffer, p - 1, p != d ? ' ': '\\');
1043 	      d = p - 2;
1044 	      buffer->next_line = p - 1;
1045 	    }
1046 	  else if (c == '?' && s[1] == '?' && _cpp_trigraph_map[s[2]])
1047 	    {
1048 	      /* Add a note regardless, for the benefit of -Wtrigraphs.  */
1049 	      add_line_note (buffer, d, s[2]);
1050 	      if (CPP_OPTION (pfile, trigraphs))
1051 		{
1052 		  *d = _cpp_trigraph_map[s[2]];
1053 		  s += 2;
1054 		}
1055 	    }
1056 	}
1057     }
1058   else
1059     {
1060       while (*s != '\n' && *s != '\r')
1061 	s++;
1062       d = (uchar *) s;
1063 
1064       /* Handle DOS line endings.  */
1065       if (*s == '\r' && s != buffer->rlimit && s[1] == '\n')
1066 	s++;
1067     }
1068 
1069  done:
1070   *d = '\n';
1071   /* A sentinel note that should never be processed.  */
1072   add_line_note (buffer, d + 1, '\n');
1073   buffer->next_line = s + 1;
1074 }
1075 
1076 /* Return true if the trigraph indicated by NOTE should be warned
1077    about in a comment.  */
1078 static bool
1079 warn_in_comment (cpp_reader *pfile, _cpp_line_note *note)
1080 {
1081   const uchar *p;
1082 
1083   /* Within comments we don't warn about trigraphs, unless the
1084      trigraph forms an escaped newline, as that may change
1085      behavior.  */
1086   if (note->type != '/')
1087     return false;
1088 
1089   /* If -trigraphs, then this was an escaped newline iff the next note
1090      is coincident.  */
1091   if (CPP_OPTION (pfile, trigraphs))
1092     return note[1].pos == note->pos;
1093 
1094   /* Otherwise, see if this forms an escaped newline.  */
1095   p = note->pos + 3;
1096   while (is_nvspace (*p))
1097     p++;
1098 
1099   /* There might have been escaped newlines between the trigraph and the
1100      newline we found.  Hence the position test.  */
1101   return (*p == '\n' && p < note[1].pos);
1102 }
1103 
1104 /* Process the notes created by add_line_note as far as the current
1105    location.  */
1106 void
1107 _cpp_process_line_notes (cpp_reader *pfile, int in_comment)
1108 {
1109   cpp_buffer *buffer = pfile->buffer;
1110 
1111   for (;;)
1112     {
1113       _cpp_line_note *note = &buffer->notes[buffer->cur_note];
1114       unsigned int col;
1115 
1116       if (note->pos > buffer->cur)
1117 	break;
1118 
1119       buffer->cur_note++;
1120       col = CPP_BUF_COLUMN (buffer, note->pos + 1);
1121 
1122       if (note->type == '\\' || note->type == ' ')
1123 	{
1124 	  if (note->type == ' ' && !in_comment)
1125 	    cpp_error_with_line (pfile, CPP_DL_WARNING, pfile->line_table->highest_line, col,
1126 				 "backslash and newline separated by space");
1127 
1128 	  if (buffer->next_line > buffer->rlimit)
1129 	    {
1130 	      cpp_error_with_line (pfile, CPP_DL_PEDWARN, pfile->line_table->highest_line, col,
1131 				   "backslash-newline at end of file");
1132 	      /* Prevent "no newline at end of file" warning.  */
1133 	      buffer->next_line = buffer->rlimit;
1134 	    }
1135 
1136 	  buffer->line_base = note->pos;
1137 	  CPP_INCREMENT_LINE (pfile, 0);
1138 	}
1139       else if (_cpp_trigraph_map[note->type])
1140 	{
1141 	  if (CPP_OPTION (pfile, warn_trigraphs)
1142 	      && (!in_comment || warn_in_comment (pfile, note)))
1143 	    {
1144 	      if (CPP_OPTION (pfile, trigraphs))
1145 		cpp_warning_with_line (pfile, CPP_W_TRIGRAPHS,
1146                                        pfile->line_table->highest_line, col,
1147 				       "trigraph ??%c converted to %c",
1148 				       note->type,
1149 				       (int) _cpp_trigraph_map[note->type]);
1150 	      else
1151 		{
1152 		  cpp_warning_with_line
1153 		    (pfile, CPP_W_TRIGRAPHS,
1154                      pfile->line_table->highest_line, col,
1155 		     "trigraph ??%c ignored, use -trigraphs to enable",
1156 		     note->type);
1157 		}
1158 	    }
1159 	}
1160       else if (note->type == 0)
1161 	/* Already processed in lex_raw_string.  */;
1162       else
1163 	abort ();
1164     }
1165 }
1166 
1167 /* Skip a C-style block comment.  We find the end of the comment by
1168    seeing if an asterisk is before every '/' we encounter.  Returns
1169    nonzero if comment terminated by EOF, zero otherwise.
1170 
1171    Buffer->cur points to the initial asterisk of the comment.  */
1172 bool
1173 _cpp_skip_block_comment (cpp_reader *pfile)
1174 {
1175   cpp_buffer *buffer = pfile->buffer;
1176   const uchar *cur = buffer->cur;
1177   uchar c;
1178 
1179   cur++;
1180   if (*cur == '/')
1181     cur++;
1182 
1183   for (;;)
1184     {
1185       /* People like decorating comments with '*', so check for '/'
1186 	 instead for efficiency.  */
1187       c = *cur++;
1188 
1189       if (c == '/')
1190 	{
1191 	  if (cur[-2] == '*')
1192 	    break;
1193 
1194 	  /* Warn about potential nested comments, but not if the '/'
1195 	     comes immediately before the true comment delimiter.
1196 	     Don't bother to get it right across escaped newlines.  */
1197 	  if (CPP_OPTION (pfile, warn_comments)
1198 	      && cur[0] == '*' && cur[1] != '/')
1199 	    {
1200 	      buffer->cur = cur;
1201 	      cpp_warning_with_line (pfile, CPP_W_COMMENTS,
1202 				     pfile->line_table->highest_line,
1203 				     CPP_BUF_COL (buffer),
1204 				     "\"/*\" within comment");
1205 	    }
1206 	}
1207       else if (c == '\n')
1208 	{
1209 	  unsigned int cols;
1210 	  buffer->cur = cur - 1;
1211 	  _cpp_process_line_notes (pfile, true);
1212 	  if (buffer->next_line >= buffer->rlimit)
1213 	    return true;
1214 	  _cpp_clean_line (pfile);
1215 
1216 	  cols = buffer->next_line - buffer->line_base;
1217 	  CPP_INCREMENT_LINE (pfile, cols);
1218 
1219 	  cur = buffer->cur;
1220 	}
1221     }
1222 
1223   buffer->cur = cur;
1224   _cpp_process_line_notes (pfile, true);
1225   return false;
1226 }
1227 
1228 /* Skip a C++ line comment, leaving buffer->cur pointing to the
1229    terminating newline.  Handles escaped newlines.  Returns nonzero
1230    if a multiline comment.  */
1231 static int
1232 skip_line_comment (cpp_reader *pfile)
1233 {
1234   cpp_buffer *buffer = pfile->buffer;
1235   location_t orig_line = pfile->line_table->highest_line;
1236 
1237   while (*buffer->cur != '\n')
1238     buffer->cur++;
1239 
1240   _cpp_process_line_notes (pfile, true);
1241   return orig_line != pfile->line_table->highest_line;
1242 }
1243 
1244 /* Skips whitespace, saving the next non-whitespace character.  */
1245 static void
1246 skip_whitespace (cpp_reader *pfile, cppchar_t c)
1247 {
1248   cpp_buffer *buffer = pfile->buffer;
1249   bool saw_NUL = false;
1250 
1251   do
1252     {
1253       /* Horizontal space always OK.  */
1254       if (c == ' ' || c == '\t')
1255 	;
1256       /* Just \f \v or \0 left.  */
1257       else if (c == '\0')
1258 	saw_NUL = true;
1259       else if (pfile->state.in_directive && CPP_PEDANTIC (pfile))
1260 	cpp_error_with_line (pfile, CPP_DL_PEDWARN, pfile->line_table->highest_line,
1261 			     CPP_BUF_COL (buffer),
1262 			     "%s in preprocessing directive",
1263 			     c == '\f' ? "form feed" : "vertical tab");
1264 
1265       c = *buffer->cur++;
1266     }
1267   /* We only want non-vertical space, i.e. ' ' \t \f \v \0.  */
1268   while (is_nvspace (c));
1269 
1270   if (saw_NUL)
1271     cpp_error (pfile, CPP_DL_WARNING, "null character(s) ignored");
1272 
1273   buffer->cur--;
1274 }
1275 
1276 /* See if the characters of a number token are valid in a name (no
1277    '.', '+' or '-').  */
1278 static int
1279 name_p (cpp_reader *pfile, const cpp_string *string)
1280 {
1281   unsigned int i;
1282 
1283   for (i = 0; i < string->len; i++)
1284     if (!is_idchar (string->text[i]))
1285       return 0;
1286 
1287   return 1;
1288 }
1289 
1290 /* After parsing an identifier or other sequence, produce a warning about
1291    sequences not in NFC/NFKC.  */
1292 static void
1293 warn_about_normalization (cpp_reader *pfile,
1294 			  const cpp_token *token,
1295 			  const struct normalize_state *s)
1296 {
1297   if (CPP_OPTION (pfile, warn_normalize) < NORMALIZE_STATE_RESULT (s)
1298       && !pfile->state.skipping)
1299     {
1300       /* Make sure that the token is printed using UCNs, even
1301 	 if we'd otherwise happily print UTF-8.  */
1302       unsigned char *buf = XNEWVEC (unsigned char, cpp_token_len (token));
1303       size_t sz;
1304 
1305       sz = cpp_spell_token (pfile, token, buf, false) - buf;
1306       if (NORMALIZE_STATE_RESULT (s) == normalized_C)
1307 	cpp_warning_with_line (pfile, CPP_W_NORMALIZE, token->src_loc, 0,
1308 			       "`%.*s' is not in NFKC", (int) sz, buf);
1309       else
1310 	cpp_warning_with_line (pfile, CPP_W_NORMALIZE, token->src_loc, 0,
1311 			       "`%.*s' is not in NFC", (int) sz, buf);
1312       free (buf);
1313     }
1314 }
1315 
1316 /* Returns TRUE if the sequence starting at buffer->cur is invalid in
1317    an identifier.  FIRST is TRUE if this starts an identifier.  */
1318 static bool
1319 forms_identifier_p (cpp_reader *pfile, int first,
1320 		    struct normalize_state *state)
1321 {
1322   cpp_buffer *buffer = pfile->buffer;
1323 
1324   if (*buffer->cur == '$')
1325     {
1326       if (!CPP_OPTION (pfile, dollars_in_ident))
1327 	return false;
1328 
1329       buffer->cur++;
1330       if (CPP_OPTION (pfile, warn_dollars) && !pfile->state.skipping)
1331 	{
1332 	  CPP_OPTION (pfile, warn_dollars) = 0;
1333 	  cpp_error (pfile, CPP_DL_PEDWARN, "'$' in identifier or number");
1334 	}
1335 
1336       return true;
1337     }
1338 
1339   /* Is this a syntactically valid UCN?  */
1340   if (CPP_OPTION (pfile, extended_identifiers)
1341       && *buffer->cur == '\\'
1342       && (buffer->cur[1] == 'u' || buffer->cur[1] == 'U'))
1343     {
1344       cppchar_t s;
1345       buffer->cur += 2;
1346       if (_cpp_valid_ucn (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
1347 			  state, &s, NULL, NULL))
1348 	return true;
1349       buffer->cur -= 2;
1350     }
1351 
1352   return false;
1353 }
1354 
1355 /* Helper function to issue error about improper __VA_OPT__ use.  */
1356 static void
1357 maybe_va_opt_error (cpp_reader *pfile)
1358 {
1359   if (CPP_PEDANTIC (pfile) && !CPP_OPTION (pfile, va_opt))
1360     {
1361       /* __VA_OPT__ should not be accepted at all, but allow it in
1362 	 system headers.  */
1363       if (!cpp_in_system_header (pfile))
1364 	cpp_error (pfile, CPP_DL_PEDWARN,
1365 		   "__VA_OPT__ is not available until C++2a");
1366     }
1367   else if (!pfile->state.va_args_ok)
1368     {
1369       /* __VA_OPT__ should only appear in the replacement list of a
1370 	 variadic macro.  */
1371       cpp_error (pfile, CPP_DL_PEDWARN,
1372 		 "__VA_OPT__ can only appear in the expansion"
1373 		 " of a C++2a variadic macro");
1374     }
1375 }
1376 
1377 /* Helper function to get the cpp_hashnode of the identifier BASE.  */
1378 static cpp_hashnode *
1379 lex_identifier_intern (cpp_reader *pfile, const uchar *base)
1380 {
1381   cpp_hashnode *result;
1382   const uchar *cur;
1383   unsigned int len;
1384   unsigned int hash = HT_HASHSTEP (0, *base);
1385 
1386   cur = base + 1;
1387   while (ISIDNUM (*cur))
1388     {
1389       hash = HT_HASHSTEP (hash, *cur);
1390       cur++;
1391     }
1392   len = cur - base;
1393   hash = HT_HASHFINISH (hash, len);
1394   result = CPP_HASHNODE (ht_lookup_with_hash (pfile->hash_table,
1395 					      base, len, hash, HT_ALLOC));
1396 
1397   /* Rarely, identifiers require diagnostics when lexed.  */
1398   if (__builtin_expect ((result->flags & NODE_DIAGNOSTIC)
1399 			&& !pfile->state.skipping, 0))
1400     {
1401       /* It is allowed to poison the same identifier twice.  */
1402       if ((result->flags & NODE_POISONED) && !pfile->state.poisoned_ok)
1403 	cpp_error (pfile, CPP_DL_ERROR, "attempt to use poisoned \"%s\"",
1404 		   NODE_NAME (result));
1405 
1406       /* Constraint 6.10.3.5: __VA_ARGS__ should only appear in the
1407 	 replacement list of a variadic macro.  */
1408       if (result == pfile->spec_nodes.n__VA_ARGS__
1409 	  && !pfile->state.va_args_ok)
1410 	{
1411 	  if (CPP_OPTION (pfile, cplusplus))
1412 	    cpp_error (pfile, CPP_DL_PEDWARN,
1413 		       "__VA_ARGS__ can only appear in the expansion"
1414 		       " of a C++11 variadic macro");
1415 	  else
1416 	    cpp_error (pfile, CPP_DL_PEDWARN,
1417 		       "__VA_ARGS__ can only appear in the expansion"
1418 		       " of a C99 variadic macro");
1419 	}
1420 
1421       if (result == pfile->spec_nodes.n__VA_OPT__)
1422 	maybe_va_opt_error (pfile);
1423 
1424       /* For -Wc++-compat, warn about use of C++ named operators.  */
1425       if (result->flags & NODE_WARN_OPERATOR)
1426 	cpp_warning (pfile, CPP_W_CXX_OPERATOR_NAMES,
1427 		     "identifier \"%s\" is a special operator name in C++",
1428 		     NODE_NAME (result));
1429     }
1430 
1431   return result;
1432 }
1433 
1434 /* Get the cpp_hashnode of an identifier specified by NAME in
1435    the current cpp_reader object.  If none is found, NULL is returned.  */
1436 cpp_hashnode *
1437 _cpp_lex_identifier (cpp_reader *pfile, const char *name)
1438 {
1439   cpp_hashnode *result;
1440   result = lex_identifier_intern (pfile, (uchar *) name);
1441   return result;
1442 }
1443 
1444 /* Lex an identifier starting at BUFFER->CUR - 1.  */
1445 static cpp_hashnode *
1446 lex_identifier (cpp_reader *pfile, const uchar *base, bool starts_ucn,
1447 		struct normalize_state *nst, cpp_hashnode **spelling)
1448 {
1449   cpp_hashnode *result;
1450   const uchar *cur;
1451   unsigned int len;
1452   unsigned int hash = HT_HASHSTEP (0, *base);
1453 
1454   cur = pfile->buffer->cur;
1455   if (! starts_ucn)
1456     {
1457       while (ISIDNUM (*cur))
1458 	{
1459 	  hash = HT_HASHSTEP (hash, *cur);
1460 	  cur++;
1461 	}
1462       NORMALIZE_STATE_UPDATE_IDNUM (nst, *(cur - 1));
1463     }
1464   pfile->buffer->cur = cur;
1465   if (starts_ucn || forms_identifier_p (pfile, false, nst))
1466     {
1467       /* Slower version for identifiers containing UCNs (or $).  */
1468       do {
1469 	while (ISIDNUM (*pfile->buffer->cur))
1470 	  {
1471 	    NORMALIZE_STATE_UPDATE_IDNUM (nst, *pfile->buffer->cur);
1472 	    pfile->buffer->cur++;
1473 	  }
1474       } while (forms_identifier_p (pfile, false, nst));
1475       result = _cpp_interpret_identifier (pfile, base,
1476 					  pfile->buffer->cur - base);
1477       *spelling = cpp_lookup (pfile, base, pfile->buffer->cur - base);
1478     }
1479   else
1480     {
1481       len = cur - base;
1482       hash = HT_HASHFINISH (hash, len);
1483 
1484       result = CPP_HASHNODE (ht_lookup_with_hash (pfile->hash_table,
1485 						  base, len, hash, HT_ALLOC));
1486       *spelling = result;
1487     }
1488 
1489   /* Rarely, identifiers require diagnostics when lexed.  */
1490   if (__builtin_expect ((result->flags & NODE_DIAGNOSTIC)
1491 			&& !pfile->state.skipping, 0))
1492     {
1493       /* It is allowed to poison the same identifier twice.  */
1494       if ((result->flags & NODE_POISONED) && !pfile->state.poisoned_ok)
1495 	cpp_error (pfile, CPP_DL_ERROR, "attempt to use poisoned \"%s\"",
1496 		   NODE_NAME (result));
1497 
1498       /* Constraint 6.10.3.5: __VA_ARGS__ should only appear in the
1499 	 replacement list of a variadic macro.  */
1500       if (result == pfile->spec_nodes.n__VA_ARGS__
1501 	  && !pfile->state.va_args_ok)
1502 	{
1503 	  if (CPP_OPTION (pfile, cplusplus))
1504 	    cpp_error (pfile, CPP_DL_PEDWARN,
1505 		       "__VA_ARGS__ can only appear in the expansion"
1506 		       " of a C++11 variadic macro");
1507 	  else
1508 	    cpp_error (pfile, CPP_DL_PEDWARN,
1509 		       "__VA_ARGS__ can only appear in the expansion"
1510 		       " of a C99 variadic macro");
1511 	}
1512 
1513       /* __VA_OPT__ should only appear in the replacement list of a
1514 	 variadic macro.  */
1515       if (result == pfile->spec_nodes.n__VA_OPT__)
1516 	maybe_va_opt_error (pfile);
1517 
1518       /* For -Wc++-compat, warn about use of C++ named operators.  */
1519       if (result->flags & NODE_WARN_OPERATOR)
1520 	cpp_warning (pfile, CPP_W_CXX_OPERATOR_NAMES,
1521 		     "identifier \"%s\" is a special operator name in C++",
1522 		     NODE_NAME (result));
1523     }
1524 
1525   return result;
1526 }
1527 
1528 /* Lex a number to NUMBER starting at BUFFER->CUR - 1.  */
1529 static void
1530 lex_number (cpp_reader *pfile, cpp_string *number,
1531 	    struct normalize_state *nst)
1532 {
1533   const uchar *cur;
1534   const uchar *base;
1535   uchar *dest;
1536 
1537   base = pfile->buffer->cur - 1;
1538   do
1539     {
1540       cur = pfile->buffer->cur;
1541 
1542       /* N.B. ISIDNUM does not include $.  */
1543       while (ISIDNUM (*cur) || *cur == '.' || DIGIT_SEP (*cur)
1544 	     || VALID_SIGN (*cur, cur[-1]))
1545 	{
1546 	  NORMALIZE_STATE_UPDATE_IDNUM (nst, *cur);
1547 	  cur++;
1548 	}
1549       /* A number can't end with a digit separator.  */
1550       while (cur > pfile->buffer->cur && DIGIT_SEP (cur[-1]))
1551 	--cur;
1552 
1553       pfile->buffer->cur = cur;
1554     }
1555   while (forms_identifier_p (pfile, false, nst));
1556 
1557   number->len = cur - base;
1558   dest = _cpp_unaligned_alloc (pfile, number->len + 1);
1559   memcpy (dest, base, number->len);
1560   dest[number->len] = '\0';
1561   number->text = dest;
1562 }
1563 
1564 /* Create a token of type TYPE with a literal spelling.  */
1565 static void
1566 create_literal (cpp_reader *pfile, cpp_token *token, const uchar *base,
1567 		unsigned int len, enum cpp_ttype type)
1568 {
1569   uchar *dest = _cpp_unaligned_alloc (pfile, len + 1);
1570 
1571   memcpy (dest, base, len);
1572   dest[len] = '\0';
1573   token->type = type;
1574   token->val.str.len = len;
1575   token->val.str.text = dest;
1576 }
1577 
1578 /* Subroutine of lex_raw_string: Append LEN chars from BASE to the buffer
1579    sequence from *FIRST_BUFF_P to LAST_BUFF_P.  */
1580 
1581 static void
1582 bufring_append (cpp_reader *pfile, const uchar *base, size_t len,
1583 		_cpp_buff **first_buff_p, _cpp_buff **last_buff_p)
1584 {
1585   _cpp_buff *first_buff = *first_buff_p;
1586   _cpp_buff *last_buff = *last_buff_p;
1587 
1588   if (first_buff == NULL)
1589     first_buff = last_buff = _cpp_get_buff (pfile, len);
1590   else if (len > BUFF_ROOM (last_buff))
1591     {
1592       size_t room = BUFF_ROOM (last_buff);
1593       memcpy (BUFF_FRONT (last_buff), base, room);
1594       BUFF_FRONT (last_buff) += room;
1595       base += room;
1596       len -= room;
1597       last_buff = _cpp_append_extend_buff (pfile, last_buff, len);
1598     }
1599 
1600   memcpy (BUFF_FRONT (last_buff), base, len);
1601   BUFF_FRONT (last_buff) += len;
1602 
1603   *first_buff_p = first_buff;
1604   *last_buff_p = last_buff;
1605 }
1606 
1607 
1608 /* Returns true if a macro has been defined.
1609    This might not work if compile with -save-temps,
1610    or preprocess separately from compilation.  */
1611 
1612 static bool
1613 is_macro(cpp_reader *pfile, const uchar *base)
1614 {
1615   const uchar *cur = base;
1616   if (! ISIDST (*cur))
1617     return false;
1618   unsigned int hash = HT_HASHSTEP (0, *cur);
1619   ++cur;
1620   while (ISIDNUM (*cur))
1621     {
1622       hash = HT_HASHSTEP (hash, *cur);
1623       ++cur;
1624     }
1625   hash = HT_HASHFINISH (hash, cur - base);
1626 
1627   cpp_hashnode *result = CPP_HASHNODE (ht_lookup_with_hash (pfile->hash_table,
1628 					base, cur - base, hash, HT_NO_INSERT));
1629 
1630   return result && cpp_macro_p (result);
1631 }
1632 
1633 /* Returns true if a literal suffix does not have the expected form
1634    and is defined as a macro.  */
1635 
1636 static bool
1637 is_macro_not_literal_suffix(cpp_reader *pfile, const uchar *base)
1638 {
1639   /* User-defined literals outside of namespace std must start with a single
1640      underscore, so assume anything of that form really is a UDL suffix.
1641      We don't need to worry about UDLs defined inside namespace std because
1642      their names are reserved, so cannot be used as macro names in valid
1643      programs.  */
1644   if (base[0] == '_' && base[1] != '_')
1645     return false;
1646   return is_macro (pfile, base);
1647 }
1648 
1649 /* Lexes a raw string.  The stored string contains the spelling, including
1650    double quotes, delimiter string, '(' and ')', any leading
1651    'L', 'u', 'U' or 'u8' and 'R' modifier.  It returns the type of the
1652    literal, or CPP_OTHER if it was not properly terminated.
1653 
1654    The spelling is NUL-terminated, but it is not guaranteed that this
1655    is the first NUL since embedded NULs are preserved.  */
1656 
1657 static void
1658 lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base,
1659 		const uchar *cur)
1660 {
1661   uchar raw_prefix[17];
1662   uchar temp_buffer[18];
1663   const uchar *orig_base;
1664   unsigned int raw_prefix_len = 0, raw_suffix_len = 0;
1665   enum raw_str_phase { RAW_STR_PREFIX, RAW_STR, RAW_STR_SUFFIX };
1666   raw_str_phase phase = RAW_STR_PREFIX;
1667   enum cpp_ttype type;
1668   size_t total_len = 0;
1669   /* Index into temp_buffer during phases other than RAW_STR,
1670      during RAW_STR phase 17 to tell BUF_APPEND that nothing should
1671      be appended to temp_buffer.  */
1672   size_t temp_buffer_len = 0;
1673   _cpp_buff *first_buff = NULL, *last_buff = NULL;
1674   size_t raw_prefix_start;
1675   _cpp_line_note *note = &pfile->buffer->notes[pfile->buffer->cur_note];
1676 
1677   type = (*base == 'L' ? CPP_WSTRING :
1678 	  *base == 'U' ? CPP_STRING32 :
1679 	  *base == 'u' ? (base[1] == '8' ? CPP_UTF8STRING : CPP_STRING16)
1680 	  : CPP_STRING);
1681 
1682 #define BUF_APPEND(STR,LEN)					\
1683       do {							\
1684 	bufring_append (pfile, (const uchar *)(STR), (LEN),	\
1685 			&first_buff, &last_buff);		\
1686 	total_len += (LEN);					\
1687 	if (__builtin_expect (temp_buffer_len < 17, 0)		\
1688 	    && (const uchar *)(STR) != base			\
1689 	    && (LEN) <= 2)					\
1690 	  {							\
1691 	    memcpy (temp_buffer + temp_buffer_len,		\
1692 		    (const uchar *)(STR), (LEN));		\
1693 	    temp_buffer_len += (LEN);				\
1694 	  }							\
1695       } while (0)
1696 
1697   orig_base = base;
1698   ++cur;
1699   raw_prefix_start = cur - base;
1700   for (;;)
1701     {
1702       cppchar_t c;
1703 
1704       /* If we previously performed any trigraph or line splicing
1705 	 transformations, undo them in between the opening and closing
1706 	 double quote.  */
1707       while (note->pos < cur)
1708 	++note;
1709       for (; note->pos == cur; ++note)
1710 	{
1711 	  switch (note->type)
1712 	    {
1713 	    case '\\':
1714 	    case ' ':
1715 	      /* Restore backslash followed by newline.  */
1716 	      BUF_APPEND (base, cur - base);
1717 	      base = cur;
1718 	      BUF_APPEND ("\\", 1);
1719 	    after_backslash:
1720 	      if (note->type == ' ')
1721 		{
1722 		  /* GNU backslash whitespace newline extension.  FIXME
1723 		     could be any sequence of non-vertical space.  When we
1724 		     can properly restore any such sequence, we should mark
1725 		     this note as handled so _cpp_process_line_notes
1726 		     doesn't warn.  */
1727 		  BUF_APPEND (" ", 1);
1728 		}
1729 
1730 	      BUF_APPEND ("\n", 1);
1731 	      break;
1732 
1733 	    case 0:
1734 	      /* Already handled.  */
1735 	      break;
1736 
1737 	    default:
1738 	      if (_cpp_trigraph_map[note->type])
1739 		{
1740 		  /* Don't warn about this trigraph in
1741 		     _cpp_process_line_notes, since trigraphs show up as
1742 		     trigraphs in raw strings.  */
1743 		  uchar type = note->type;
1744 		  note->type = 0;
1745 
1746 		  if (!CPP_OPTION (pfile, trigraphs))
1747 		    /* If we didn't convert the trigraph in the first
1748 		       place, don't do anything now either.  */
1749 		    break;
1750 
1751 		  BUF_APPEND (base, cur - base);
1752 		  base = cur;
1753 		  BUF_APPEND ("??", 2);
1754 
1755 		  /* ??/ followed by newline gets two line notes, one for
1756 		     the trigraph and one for the backslash/newline.  */
1757 		  if (type == '/' && note[1].pos == cur)
1758 		    {
1759 		      if (note[1].type != '\\'
1760 			  && note[1].type != ' ')
1761 			abort ();
1762 		      BUF_APPEND ("/", 1);
1763 		      ++note;
1764 		      goto after_backslash;
1765 		    }
1766 		  else
1767 		    {
1768 		      /* Skip the replacement character.  */
1769 		      base = ++cur;
1770 		      BUF_APPEND (&type, 1);
1771 		      c = type;
1772 		      goto check_c;
1773 		    }
1774 		}
1775 	      else
1776 		abort ();
1777 	      break;
1778 	    }
1779 	}
1780       c = *cur++;
1781       if (__builtin_expect (temp_buffer_len < 17, 0))
1782 	temp_buffer[temp_buffer_len++] = c;
1783 
1784      check_c:
1785       if (phase == RAW_STR_PREFIX)
1786 	{
1787 	  while (raw_prefix_len < temp_buffer_len)
1788 	    {
1789 	      raw_prefix[raw_prefix_len] = temp_buffer[raw_prefix_len];
1790 	      switch (raw_prefix[raw_prefix_len])
1791 		{
1792 		case ' ': case '(': case ')': case '\\': case '\t':
1793 		case '\v': case '\f': case '\n': default:
1794 		  break;
1795 		/* Basic source charset except the above chars.  */
1796 		case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
1797 		case 'g': case 'h': case 'i': case 'j': case 'k': case 'l':
1798 		case 'm': case 'n': case 'o': case 'p': case 'q': case 'r':
1799 		case 's': case 't': case 'u': case 'v': case 'w': case 'x':
1800 		case 'y': case 'z':
1801 		case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
1802 		case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
1803 		case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
1804 		case 'S': case 'T': case 'U': case 'V': case 'W': case 'X':
1805 		case 'Y': case 'Z':
1806 		case '0': case '1': case '2': case '3': case '4': case '5':
1807 		case '6': case '7': case '8': case '9':
1808 		case '_': case '{': case '}': case '#': case '[': case ']':
1809 		case '<': case '>': case '%': case ':': case ';': case '.':
1810 		case '?': case '*': case '+': case '-': case '/': case '^':
1811 		case '&': case '|': case '~': case '!': case '=': case ',':
1812 		case '"': case '\'':
1813 		  if (raw_prefix_len < 16)
1814 		    {
1815 		      raw_prefix_len++;
1816 		      continue;
1817 		    }
1818 		  break;
1819 		}
1820 
1821 	      if (raw_prefix[raw_prefix_len] != '(')
1822 		{
1823 		  int col = CPP_BUF_COLUMN (pfile->buffer, cur) + 1;
1824 		  if (raw_prefix_len == 16)
1825 		    cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc,
1826 					 col, "raw string delimiter longer "
1827 					      "than 16 characters");
1828 		  else if (raw_prefix[raw_prefix_len] == '\n')
1829 		    cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc,
1830 					 col, "invalid new-line in raw "
1831 					      "string delimiter");
1832 		  else
1833 		    cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc,
1834 					 col, "invalid character '%c' in "
1835 					      "raw string delimiter",
1836 					 (int) raw_prefix[raw_prefix_len]);
1837 		  pfile->buffer->cur = orig_base + raw_prefix_start - 1;
1838 		  create_literal (pfile, token, orig_base,
1839 				  raw_prefix_start - 1, CPP_OTHER);
1840 		  if (first_buff)
1841 		    _cpp_release_buff (pfile, first_buff);
1842 		  return;
1843 		}
1844 	      raw_prefix[raw_prefix_len] = '"';
1845 	      phase = RAW_STR;
1846 	      /* Nothing should be appended to temp_buffer during
1847 		 RAW_STR phase.  */
1848 	      temp_buffer_len = 17;
1849 	      break;
1850 	    }
1851 	  continue;
1852 	}
1853       else if (phase == RAW_STR_SUFFIX)
1854 	{
1855 	  while (raw_suffix_len <= raw_prefix_len
1856 		 && raw_suffix_len < temp_buffer_len
1857 		 && temp_buffer[raw_suffix_len] == raw_prefix[raw_suffix_len])
1858 	    raw_suffix_len++;
1859 	  if (raw_suffix_len > raw_prefix_len)
1860 	    break;
1861 	  if (raw_suffix_len == temp_buffer_len)
1862 	    continue;
1863 	  phase = RAW_STR;
1864 	  /* Nothing should be appended to temp_buffer during
1865 	     RAW_STR phase.  */
1866 	  temp_buffer_len = 17;
1867 	}
1868       if (c == ')')
1869 	{
1870 	  phase = RAW_STR_SUFFIX;
1871 	  raw_suffix_len = 0;
1872 	  temp_buffer_len = 0;
1873 	}
1874       else if (c == '\n')
1875 	{
1876 	  if (pfile->state.in_directive
1877 	      || (pfile->state.parsing_args
1878 		  && pfile->buffer->next_line >= pfile->buffer->rlimit))
1879 	    {
1880 	      cur--;
1881 	      type = CPP_OTHER;
1882 	      cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc, 0,
1883 				   "unterminated raw string");
1884 	      break;
1885 	    }
1886 
1887 	  BUF_APPEND (base, cur - base);
1888 
1889 	  if (pfile->buffer->cur < pfile->buffer->rlimit)
1890 	    CPP_INCREMENT_LINE (pfile, 0);
1891 	  pfile->buffer->need_line = true;
1892 
1893 	  pfile->buffer->cur = cur-1;
1894 	  _cpp_process_line_notes (pfile, false);
1895 	  if (!_cpp_get_fresh_line (pfile))
1896 	    {
1897 	      location_t src_loc = token->src_loc;
1898 	      token->type = CPP_EOF;
1899 	      /* Tell the compiler the line number of the EOF token.  */
1900 	      token->src_loc = pfile->line_table->highest_line;
1901 	      token->flags = BOL;
1902 	      if (first_buff != NULL)
1903 		_cpp_release_buff (pfile, first_buff);
1904 	      cpp_error_with_line (pfile, CPP_DL_ERROR, src_loc, 0,
1905 				   "unterminated raw string");
1906 	      return;
1907 	    }
1908 
1909 	  cur = base = pfile->buffer->cur;
1910 	  note = &pfile->buffer->notes[pfile->buffer->cur_note];
1911 	}
1912     }
1913 
1914   if (CPP_OPTION (pfile, user_literals))
1915     {
1916       /* If a string format macro, say from inttypes.h, is placed touching
1917 	 a string literal it could be parsed as a C++11 user-defined string
1918 	 literal thus breaking the program.  */
1919       if (is_macro_not_literal_suffix (pfile, cur))
1920 	{
1921 	  /* Raise a warning, but do not consume subsequent tokens.  */
1922 	  if (CPP_OPTION (pfile, warn_literal_suffix) && !pfile->state.skipping)
1923 	    cpp_warning_with_line (pfile, CPP_W_LITERAL_SUFFIX,
1924 				   token->src_loc, 0,
1925 				   "invalid suffix on literal; C++11 requires "
1926 				   "a space between literal and string macro");
1927 	}
1928       /* Grab user defined literal suffix.  */
1929       else if (ISIDST (*cur))
1930 	{
1931 	  type = cpp_userdef_string_add_type (type);
1932 	  ++cur;
1933 
1934 	  while (ISIDNUM (*cur))
1935 	    ++cur;
1936 	}
1937     }
1938 
1939   pfile->buffer->cur = cur;
1940   if (first_buff == NULL)
1941     create_literal (pfile, token, base, cur - base, type);
1942   else
1943     {
1944       uchar *dest = _cpp_unaligned_alloc (pfile, total_len + (cur - base) + 1);
1945 
1946       token->type = type;
1947       token->val.str.len = total_len + (cur - base);
1948       token->val.str.text = dest;
1949       last_buff = first_buff;
1950       while (last_buff != NULL)
1951 	{
1952 	  memcpy (dest, last_buff->base,
1953 		  BUFF_FRONT (last_buff) - last_buff->base);
1954 	  dest += BUFF_FRONT (last_buff) - last_buff->base;
1955 	  last_buff = last_buff->next;
1956 	}
1957       _cpp_release_buff (pfile, first_buff);
1958       memcpy (dest, base, cur - base);
1959       dest[cur - base] = '\0';
1960     }
1961 }
1962 
1963 /* Lexes a string, character constant, or angle-bracketed header file
1964    name.  The stored string contains the spelling, including opening
1965    quote and any leading 'L', 'u', 'U' or 'u8' and optional
1966    'R' modifier.  It returns the type of the literal, or CPP_OTHER
1967    if it was not properly terminated, or CPP_LESS for an unterminated
1968    header name which must be relexed as normal tokens.
1969 
1970    The spelling is NUL-terminated, but it is not guaranteed that this
1971    is the first NUL since embedded NULs are preserved.  */
1972 static void
1973 lex_string (cpp_reader *pfile, cpp_token *token, const uchar *base)
1974 {
1975   bool saw_NUL = false;
1976   const uchar *cur;
1977   cppchar_t terminator;
1978   enum cpp_ttype type;
1979 
1980   cur = base;
1981   terminator = *cur++;
1982   if (terminator == 'L' || terminator == 'U')
1983     terminator = *cur++;
1984   else if (terminator == 'u')
1985     {
1986       terminator = *cur++;
1987       if (terminator == '8')
1988 	terminator = *cur++;
1989     }
1990   if (terminator == 'R')
1991     {
1992       lex_raw_string (pfile, token, base, cur);
1993       return;
1994     }
1995   if (terminator == '"')
1996     type = (*base == 'L' ? CPP_WSTRING :
1997 	    *base == 'U' ? CPP_STRING32 :
1998 	    *base == 'u' ? (base[1] == '8' ? CPP_UTF8STRING : CPP_STRING16)
1999 			 : CPP_STRING);
2000   else if (terminator == '\'')
2001     type = (*base == 'L' ? CPP_WCHAR :
2002 	    *base == 'U' ? CPP_CHAR32 :
2003 	    *base == 'u' ? (base[1] == '8' ? CPP_UTF8CHAR : CPP_CHAR16)
2004 			 : CPP_CHAR);
2005   else
2006     terminator = '>', type = CPP_HEADER_NAME;
2007 
2008   for (;;)
2009     {
2010       cppchar_t c = *cur++;
2011 
2012       /* In #include-style directives, terminators are not escapable.  */
2013       if (c == '\\' && !pfile->state.angled_headers && *cur != '\n')
2014 	cur++;
2015       else if (c == terminator)
2016 	break;
2017       else if (c == '\n')
2018 	{
2019 	  cur--;
2020 	  /* Unmatched quotes always yield undefined behavior, but
2021 	     greedy lexing means that what appears to be an unterminated
2022 	     header name may actually be a legitimate sequence of tokens.  */
2023 	  if (terminator == '>')
2024 	    {
2025 	      token->type = CPP_LESS;
2026 	      return;
2027 	    }
2028 	  type = CPP_OTHER;
2029 	  break;
2030 	}
2031       else if (c == '\0')
2032 	saw_NUL = true;
2033     }
2034 
2035   if (saw_NUL && !pfile->state.skipping)
2036     cpp_error (pfile, CPP_DL_WARNING,
2037 	       "null character(s) preserved in literal");
2038 
2039   if (type == CPP_OTHER && CPP_OPTION (pfile, lang) != CLK_ASM)
2040     cpp_error (pfile, CPP_DL_PEDWARN, "missing terminating %c character",
2041 	       (int) terminator);
2042 
2043   if (CPP_OPTION (pfile, user_literals))
2044     {
2045       /* If a string format macro, say from inttypes.h, is placed touching
2046 	 a string literal it could be parsed as a C++11 user-defined string
2047 	 literal thus breaking the program.  */
2048       if (is_macro_not_literal_suffix (pfile, cur))
2049 	{
2050 	  /* Raise a warning, but do not consume subsequent tokens.  */
2051 	  if (CPP_OPTION (pfile, warn_literal_suffix) && !pfile->state.skipping)
2052 	    cpp_warning_with_line (pfile, CPP_W_LITERAL_SUFFIX,
2053 				   token->src_loc, 0,
2054 				   "invalid suffix on literal; C++11 requires "
2055 				   "a space between literal and string macro");
2056 	}
2057       /* Grab user defined literal suffix.  */
2058       else if (ISIDST (*cur))
2059 	{
2060 	  type = cpp_userdef_char_add_type (type);
2061 	  type = cpp_userdef_string_add_type (type);
2062           ++cur;
2063 
2064 	  while (ISIDNUM (*cur))
2065 	    ++cur;
2066 	}
2067     }
2068   else if (CPP_OPTION (pfile, cpp_warn_cxx11_compat)
2069 	   && is_macro (pfile, cur)
2070 	   && !pfile->state.skipping)
2071     cpp_warning_with_line (pfile, CPP_W_CXX11_COMPAT,
2072 			   token->src_loc, 0, "C++11 requires a space "
2073 			   "between string literal and macro");
2074 
2075   pfile->buffer->cur = cur;
2076   create_literal (pfile, token, base, cur - base, type);
2077 }
2078 
2079 /* Return the comment table. The client may not make any assumption
2080    about the ordering of the table.  */
2081 cpp_comment_table *
2082 cpp_get_comments (cpp_reader *pfile)
2083 {
2084   return &pfile->comments;
2085 }
2086 
2087 /* Append a comment to the end of the comment table. */
2088 static void
2089 store_comment (cpp_reader *pfile, cpp_token *token)
2090 {
2091   int len;
2092 
2093   if (pfile->comments.allocated == 0)
2094     {
2095       pfile->comments.allocated = 256;
2096       pfile->comments.entries = (cpp_comment *) xmalloc
2097 	(pfile->comments.allocated * sizeof (cpp_comment));
2098     }
2099 
2100   if (pfile->comments.count == pfile->comments.allocated)
2101     {
2102       pfile->comments.allocated *= 2;
2103       pfile->comments.entries = (cpp_comment *) xrealloc
2104 	(pfile->comments.entries,
2105 	 pfile->comments.allocated * sizeof (cpp_comment));
2106     }
2107 
2108   len = token->val.str.len;
2109 
2110   /* Copy comment. Note, token may not be NULL terminated. */
2111   pfile->comments.entries[pfile->comments.count].comment =
2112     (char *) xmalloc (sizeof (char) * (len + 1));
2113   memcpy (pfile->comments.entries[pfile->comments.count].comment,
2114 	  token->val.str.text, len);
2115   pfile->comments.entries[pfile->comments.count].comment[len] = '\0';
2116 
2117   /* Set source location. */
2118   pfile->comments.entries[pfile->comments.count].sloc = token->src_loc;
2119 
2120   /* Increment the count of entries in the comment table. */
2121   pfile->comments.count++;
2122 }
2123 
2124 /* The stored comment includes the comment start and any terminator.  */
2125 static void
2126 save_comment (cpp_reader *pfile, cpp_token *token, const unsigned char *from,
2127 	      cppchar_t type)
2128 {
2129   unsigned char *buffer;
2130   unsigned int len, clen, i;
2131   int convert_to_c = (pfile->state.in_directive || pfile->state.parsing_args)
2132     && type == '/';
2133 
2134   len = pfile->buffer->cur - from + 1; /* + 1 for the initial '/'.  */
2135 
2136   /* C++ comments probably (not definitely) have moved past a new
2137      line, which we don't want to save in the comment.  */
2138   if (is_vspace (pfile->buffer->cur[-1]))
2139     len--;
2140 
2141   /* If we are currently in a directive or in argument parsing, then
2142      we need to store all C++ comments as C comments internally, and
2143      so we need to allocate a little extra space in that case.
2144 
2145      Note that the only time we encounter a directive here is
2146      when we are saving comments in a "#define".  */
2147   clen = convert_to_c ? len + 2 : len;
2148 
2149   buffer = _cpp_unaligned_alloc (pfile, clen);
2150 
2151   token->type = CPP_COMMENT;
2152   token->val.str.len = clen;
2153   token->val.str.text = buffer;
2154 
2155   buffer[0] = '/';
2156   memcpy (buffer + 1, from, len - 1);
2157 
2158   /* Finish conversion to a C comment, if necessary.  */
2159   if (convert_to_c)
2160     {
2161       buffer[1] = '*';
2162       buffer[clen - 2] = '*';
2163       buffer[clen - 1] = '/';
2164       /* As there can be in a C++ comments illegal sequences for C comments
2165          we need to filter them out.  */
2166       for (i = 2; i < (clen - 2); i++)
2167         if (buffer[i] == '/' && (buffer[i - 1] == '*' || buffer[i + 1] == '*'))
2168           buffer[i] = '|';
2169     }
2170 
2171   /* Finally store this comment for use by clients of libcpp. */
2172   store_comment (pfile, token);
2173 }
2174 
2175 /* Returns true if comment at COMMENT_START is a recognized FALLTHROUGH
2176    comment.  */
2177 
2178 static bool
2179 fallthrough_comment_p (cpp_reader *pfile, const unsigned char *comment_start)
2180 {
2181   const unsigned char *from = comment_start + 1;
2182 
2183   switch (CPP_OPTION (pfile, cpp_warn_implicit_fallthrough))
2184     {
2185       /* For both -Wimplicit-fallthrough=0 and -Wimplicit-fallthrough=5 we
2186 	 don't recognize any comments.  The latter only checks attributes,
2187 	 the former doesn't warn.  */
2188     case 0:
2189     default:
2190       return false;
2191       /* -Wimplicit-fallthrough=1 considers any comment, no matter what
2192 	 content it has.  */
2193     case 1:
2194       return true;
2195     case 2:
2196       /* -Wimplicit-fallthrough=2 looks for (case insensitive)
2197 	 .*falls?[ \t-]*thr(u|ough).* regex.  */
2198       for (; (size_t) (pfile->buffer->cur - from) >= sizeof "fallthru" - 1;
2199 	   from++)
2200 	{
2201 	  /* Is there anything like strpbrk with upper boundary, or
2202 	     memchr looking for 2 characters rather than just one?  */
2203 	  if (from[0] != 'f' && from[0] != 'F')
2204 	    continue;
2205 	  if (from[1] != 'a' && from[1] != 'A')
2206 	    continue;
2207 	  if (from[2] != 'l' && from[2] != 'L')
2208 	    continue;
2209 	  if (from[3] != 'l' && from[3] != 'L')
2210 	    continue;
2211 	  from += sizeof "fall" - 1;
2212 	  if (from[0] == 's' || from[0] == 'S')
2213 	    from++;
2214 	  while (*from == ' ' || *from == '\t' || *from == '-')
2215 	    from++;
2216 	  if (from[0] != 't' && from[0] != 'T')
2217 	    continue;
2218 	  if (from[1] != 'h' && from[1] != 'H')
2219 	    continue;
2220 	  if (from[2] != 'r' && from[2] != 'R')
2221 	    continue;
2222 	  if (from[3] == 'u' || from[3] == 'U')
2223 	    return true;
2224 	  if (from[3] != 'o' && from[3] != 'O')
2225 	    continue;
2226 	  if (from[4] != 'u' && from[4] != 'U')
2227 	    continue;
2228 	  if (from[5] != 'g' && from[5] != 'G')
2229 	    continue;
2230 	  if (from[6] != 'h' && from[6] != 'H')
2231 	    continue;
2232 	  return true;
2233 	}
2234       return false;
2235     case 3:
2236     case 4:
2237       break;
2238     }
2239 
2240   /* Whole comment contents:
2241      -fallthrough
2242      @fallthrough@
2243    */
2244   if (*from == '-' || *from == '@')
2245     {
2246       size_t len = sizeof "fallthrough" - 1;
2247       if ((size_t) (pfile->buffer->cur - from - 1) < len)
2248 	return false;
2249       if (memcmp (from + 1, "fallthrough", len))
2250 	return false;
2251       if (*from == '@')
2252 	{
2253 	  if (from[len + 1] != '@')
2254 	    return false;
2255 	  len++;
2256 	}
2257       from += 1 + len;
2258     }
2259   /* Whole comment contents (regex):
2260      lint -fallthrough[ \t]*
2261    */
2262   else if (*from == 'l')
2263     {
2264       size_t len = sizeof "int -fallthrough" - 1;
2265       if ((size_t) (pfile->buffer->cur - from - 1) < len)
2266 	return false;
2267       if (memcmp (from + 1, "int -fallthrough", len))
2268 	return false;
2269       from += 1 + len;
2270       while (*from == ' ' || *from == '\t')
2271 	from++;
2272     }
2273   /* Whole comment contents (regex):
2274      [ \t]*FALLTHR(U|OUGH)[ \t]*
2275    */
2276   else if (CPP_OPTION (pfile, cpp_warn_implicit_fallthrough) == 4)
2277     {
2278       while (*from == ' ' || *from == '\t')
2279 	from++;
2280       if ((size_t) (pfile->buffer->cur - from)  < sizeof "FALLTHRU" - 1)
2281 	return false;
2282       if (memcmp (from, "FALLTHR", sizeof "FALLTHR" - 1))
2283 	return false;
2284       from += sizeof "FALLTHR" - 1;
2285       if (*from == 'U')
2286 	from++;
2287       else if ((size_t) (pfile->buffer->cur - from)  < sizeof "OUGH" - 1)
2288 	return false;
2289       else if (memcmp (from, "OUGH", sizeof "OUGH" - 1))
2290 	return false;
2291       else
2292 	from += sizeof "OUGH" - 1;
2293       while (*from == ' ' || *from == '\t')
2294 	from++;
2295     }
2296   /* Whole comment contents (regex):
2297      [ \t.!]*(ELSE,? |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \t.!]*(-[^\n\r]*)?
2298      [ \t.!]*(Else,? |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[ \t.!]*(-[^\n\r]*)?
2299      [ \t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?
2300    */
2301   else
2302     {
2303       while (*from == ' ' || *from == '\t' || *from == '.' || *from == '!')
2304 	from++;
2305       unsigned char f = *from;
2306       bool all_upper = false;
2307       if (f == 'E' || f == 'e')
2308 	{
2309 	  if ((size_t) (pfile->buffer->cur - from)
2310 	      < sizeof "else fallthru" - 1)
2311 	    return false;
2312 	  if (f == 'E' && memcmp (from + 1, "LSE", sizeof "LSE" - 1) == 0)
2313 	    all_upper = true;
2314 	  else if (memcmp (from + 1, "lse", sizeof "lse" - 1))
2315 	    return false;
2316 	  from += sizeof "else" - 1;
2317 	  if (*from == ',')
2318 	    from++;
2319 	  if (*from != ' ')
2320 	    return false;
2321 	  from++;
2322 	  if (all_upper && *from == 'f')
2323 	    return false;
2324 	  if (f == 'e' && *from == 'F')
2325 	    return false;
2326 	  f = *from;
2327 	}
2328       else if (f == 'I' || f == 'i')
2329 	{
2330 	  if ((size_t) (pfile->buffer->cur - from)
2331 	      < sizeof "intentional fallthru" - 1)
2332 	    return false;
2333 	  if (f == 'I' && memcmp (from + 1, "NTENTIONAL",
2334 				  sizeof "NTENTIONAL" - 1) == 0)
2335 	    all_upper = true;
2336 	  else if (memcmp (from + 1, "ntentional",
2337 			   sizeof "ntentional" - 1))
2338 	    return false;
2339 	  from += sizeof "intentional" - 1;
2340 	  if (*from == ' ')
2341 	    {
2342 	      from++;
2343 	      if (all_upper && *from == 'f')
2344 		return false;
2345 	    }
2346 	  else if (all_upper)
2347 	    {
2348 	      if (memcmp (from, "LY F", sizeof "LY F" - 1))
2349 		return false;
2350 	      from += sizeof "LY " - 1;
2351 	    }
2352 	  else
2353 	    {
2354 	      if (memcmp (from, "ly ", sizeof "ly " - 1))
2355 		return false;
2356 	      from += sizeof "ly " - 1;
2357 	    }
2358 	  if (f == 'i' && *from == 'F')
2359 	    return false;
2360 	  f = *from;
2361 	}
2362       if (f != 'F' && f != 'f')
2363 	return false;
2364       if ((size_t) (pfile->buffer->cur - from) < sizeof "fallthru" - 1)
2365 	return false;
2366       if (f == 'F' && memcmp (from + 1, "ALL", sizeof "ALL" - 1) == 0)
2367 	all_upper = true;
2368       else if (all_upper)
2369 	return false;
2370       else if (memcmp (from + 1, "all", sizeof "all" - 1))
2371 	return false;
2372       from += sizeof "fall" - 1;
2373       if (*from == (all_upper ? 'S' : 's') && from[1] == ' ')
2374 	from += 2;
2375       else if (*from == ' ' || *from == '-')
2376 	from++;
2377       else if (*from != (all_upper ? 'T' : 't'))
2378 	return false;
2379       if ((f == 'f' || *from != 'T') && (all_upper || *from != 't'))
2380 	return false;
2381       if ((size_t) (pfile->buffer->cur - from) < sizeof "thru" - 1)
2382 	return false;
2383       if (memcmp (from + 1, all_upper ? "HRU" : "hru", sizeof "hru" - 1))
2384 	{
2385 	  if ((size_t) (pfile->buffer->cur - from) < sizeof "through" - 1)
2386 	    return false;
2387 	  if (memcmp (from + 1, all_upper ? "HROUGH" : "hrough",
2388 		      sizeof "hrough" - 1))
2389 	    return false;
2390 	  from += sizeof "through" - 1;
2391 	}
2392       else
2393 	from += sizeof "thru" - 1;
2394       while (*from == ' ' || *from == '\t' || *from == '.' || *from == '!')
2395 	from++;
2396       if (*from == '-')
2397 	{
2398 	  from++;
2399 	  if (*comment_start == '*')
2400 	    {
2401 	      do
2402 		{
2403 		  while (*from && *from != '*'
2404 			 && *from != '\n' && *from != '\r')
2405 		    from++;
2406 		  if (*from != '*' || from[1] == '/')
2407 		    break;
2408 		  from++;
2409 		}
2410 	      while (1);
2411 	    }
2412 	  else
2413 	    while (*from && *from != '\n' && *from != '\r')
2414 	      from++;
2415 	}
2416     }
2417   /* C block comment.  */
2418   if (*comment_start == '*')
2419     {
2420       if (*from != '*' || from[1] != '/')
2421 	return false;
2422     }
2423   /* C++ line comment.  */
2424   else if (*from != '\n')
2425     return false;
2426 
2427   return true;
2428 }
2429 
2430 /* Allocate COUNT tokens for RUN.  */
2431 void
2432 _cpp_init_tokenrun (tokenrun *run, unsigned int count)
2433 {
2434   run->base = XNEWVEC (cpp_token, count);
2435   run->limit = run->base + count;
2436   run->next = NULL;
2437 }
2438 
2439 /* Returns the next tokenrun, or creates one if there is none.  */
2440 static tokenrun *
2441 next_tokenrun (tokenrun *run)
2442 {
2443   if (run->next == NULL)
2444     {
2445       run->next = XNEW (tokenrun);
2446       run->next->prev = run;
2447       _cpp_init_tokenrun (run->next, 250);
2448     }
2449 
2450   return run->next;
2451 }
2452 
2453 /* Return the number of not yet processed token in a given
2454    context.  */
2455 int
2456 _cpp_remaining_tokens_num_in_context (cpp_context *context)
2457 {
2458   if (context->tokens_kind == TOKENS_KIND_DIRECT)
2459     return (LAST (context).token - FIRST (context).token);
2460   else if (context->tokens_kind == TOKENS_KIND_INDIRECT
2461 	   || context->tokens_kind == TOKENS_KIND_EXTENDED)
2462     return (LAST (context).ptoken - FIRST (context).ptoken);
2463   else
2464       abort ();
2465 }
2466 
2467 /* Returns the token present at index INDEX in a given context.  If
2468    INDEX is zero, the next token to be processed is returned.  */
2469 static const cpp_token*
2470 _cpp_token_from_context_at (cpp_context *context, int index)
2471 {
2472   if (context->tokens_kind == TOKENS_KIND_DIRECT)
2473     return &(FIRST (context).token[index]);
2474   else if (context->tokens_kind == TOKENS_KIND_INDIRECT
2475 	   || context->tokens_kind == TOKENS_KIND_EXTENDED)
2476     return FIRST (context).ptoken[index];
2477  else
2478    abort ();
2479 }
2480 
2481 /* Look ahead in the input stream.  */
2482 const cpp_token *
2483 cpp_peek_token (cpp_reader *pfile, int index)
2484 {
2485   cpp_context *context = pfile->context;
2486   const cpp_token *peektok;
2487   int count;
2488 
2489   /* First, scan through any pending cpp_context objects.  */
2490   while (context->prev)
2491     {
2492       ptrdiff_t sz = _cpp_remaining_tokens_num_in_context (context);
2493 
2494       if (index < (int) sz)
2495         return _cpp_token_from_context_at (context, index);
2496       index -= (int) sz;
2497       context = context->prev;
2498     }
2499 
2500   /* We will have to read some new tokens after all (and do so
2501      without invalidating preceding tokens).  */
2502   count = index;
2503   pfile->keep_tokens++;
2504 
2505   /* For peeked tokens temporarily disable line_change reporting,
2506      until the tokens are parsed for real.  */
2507   void (*line_change) (cpp_reader *, const cpp_token *, int)
2508     = pfile->cb.line_change;
2509   pfile->cb.line_change = NULL;
2510 
2511   do
2512     {
2513       peektok = _cpp_lex_token (pfile);
2514       if (peektok->type == CPP_EOF)
2515 	{
2516 	  index--;
2517 	  break;
2518 	}
2519     }
2520   while (index--);
2521 
2522   _cpp_backup_tokens_direct (pfile, count - index);
2523   pfile->keep_tokens--;
2524   pfile->cb.line_change = line_change;
2525 
2526   return peektok;
2527 }
2528 
2529 /* Allocate a single token that is invalidated at the same time as the
2530    rest of the tokens on the line.  Has its line and col set to the
2531    same as the last lexed token, so that diagnostics appear in the
2532    right place.  */
2533 cpp_token *
2534 _cpp_temp_token (cpp_reader *pfile)
2535 {
2536   cpp_token *old, *result;
2537   ptrdiff_t sz = pfile->cur_run->limit - pfile->cur_token;
2538   ptrdiff_t la = (ptrdiff_t) pfile->lookaheads;
2539 
2540   old = pfile->cur_token - 1;
2541   /* Any pre-existing lookaheads must not be clobbered.  */
2542   if (la)
2543     {
2544       if (sz <= la)
2545         {
2546           tokenrun *next = next_tokenrun (pfile->cur_run);
2547 
2548           if (sz < la)
2549             memmove (next->base + 1, next->base,
2550                      (la - sz) * sizeof (cpp_token));
2551 
2552           next->base[0] = pfile->cur_run->limit[-1];
2553         }
2554 
2555       if (sz > 1)
2556         memmove (pfile->cur_token + 1, pfile->cur_token,
2557                  MIN (la, sz - 1) * sizeof (cpp_token));
2558     }
2559 
2560   if (!sz && pfile->cur_token == pfile->cur_run->limit)
2561     {
2562       pfile->cur_run = next_tokenrun (pfile->cur_run);
2563       pfile->cur_token = pfile->cur_run->base;
2564     }
2565 
2566   result = pfile->cur_token++;
2567   result->src_loc = old->src_loc;
2568   return result;
2569 }
2570 
2571 /* Lex a token into RESULT (external interface).  Takes care of issues
2572    like directive handling, token lookahead, multiple include
2573    optimization and skipping.  */
2574 const cpp_token *
2575 _cpp_lex_token (cpp_reader *pfile)
2576 {
2577   cpp_token *result;
2578 
2579   for (;;)
2580     {
2581       if (pfile->cur_token == pfile->cur_run->limit)
2582 	{
2583 	  pfile->cur_run = next_tokenrun (pfile->cur_run);
2584 	  pfile->cur_token = pfile->cur_run->base;
2585 	}
2586       /* We assume that the current token is somewhere in the current
2587 	 run.  */
2588       if (pfile->cur_token < pfile->cur_run->base
2589 	  || pfile->cur_token >= pfile->cur_run->limit)
2590 	abort ();
2591 
2592       if (pfile->lookaheads)
2593 	{
2594 	  pfile->lookaheads--;
2595 	  result = pfile->cur_token++;
2596 	}
2597       else
2598 	result = _cpp_lex_direct (pfile);
2599 
2600       if (result->flags & BOL)
2601 	{
2602 	  /* Is this a directive.  If _cpp_handle_directive returns
2603 	     false, it is an assembler #.  */
2604 	  if (result->type == CPP_HASH
2605 	      /* 6.10.3 p 11: Directives in a list of macro arguments
2606 		 gives undefined behavior.  This implementation
2607 		 handles the directive as normal.  */
2608 	      && pfile->state.parsing_args != 1)
2609 	    {
2610 	      if (_cpp_handle_directive (pfile, result->flags & PREV_WHITE))
2611 		{
2612 		  if (pfile->directive_result.type == CPP_PADDING)
2613 		    continue;
2614 		  result = &pfile->directive_result;
2615 		}
2616 	    }
2617 	  else if (pfile->state.in_deferred_pragma)
2618 	    result = &pfile->directive_result;
2619 
2620 	  if (pfile->cb.line_change && !pfile->state.skipping)
2621 	    pfile->cb.line_change (pfile, result, pfile->state.parsing_args);
2622 	}
2623 
2624       /* We don't skip tokens in directives.  */
2625       if (pfile->state.in_directive || pfile->state.in_deferred_pragma)
2626 	break;
2627 
2628       /* Outside a directive, invalidate controlling macros.  At file
2629 	 EOF, _cpp_lex_direct takes care of popping the buffer, so we never
2630 	 get here and MI optimization works.  */
2631       pfile->mi_valid = false;
2632 
2633       if (!pfile->state.skipping || result->type == CPP_EOF)
2634 	break;
2635     }
2636 
2637   return result;
2638 }
2639 
2640 /* Returns true if a fresh line has been loaded.  */
2641 bool
2642 _cpp_get_fresh_line (cpp_reader *pfile)
2643 {
2644   int return_at_eof;
2645 
2646   /* We can't get a new line until we leave the current directive.  */
2647   if (pfile->state.in_directive)
2648     return false;
2649 
2650   for (;;)
2651     {
2652       cpp_buffer *buffer = pfile->buffer;
2653 
2654       if (!buffer->need_line)
2655 	return true;
2656 
2657       if (buffer->next_line < buffer->rlimit)
2658 	{
2659 	  _cpp_clean_line (pfile);
2660 	  return true;
2661 	}
2662 
2663       /* First, get out of parsing arguments state.  */
2664       if (pfile->state.parsing_args)
2665 	return false;
2666 
2667       /* End of buffer.  Non-empty files should end in a newline.  */
2668       if (buffer->buf != buffer->rlimit
2669 	  && buffer->next_line > buffer->rlimit
2670 	  && !buffer->from_stage3)
2671 	{
2672 	  /* Clip to buffer size.  */
2673 	  buffer->next_line = buffer->rlimit;
2674 	}
2675 
2676       return_at_eof = buffer->return_at_eof;
2677       _cpp_pop_buffer (pfile);
2678       if (pfile->buffer == NULL || return_at_eof)
2679 	return false;
2680     }
2681 }
2682 
2683 #define IF_NEXT_IS(CHAR, THEN_TYPE, ELSE_TYPE)		\
2684   do							\
2685     {							\
2686       result->type = ELSE_TYPE;				\
2687       if (*buffer->cur == CHAR)				\
2688 	buffer->cur++, result->type = THEN_TYPE;	\
2689     }							\
2690   while (0)
2691 
2692 /* Lex a token into pfile->cur_token, which is also incremented, to
2693    get diagnostics pointing to the correct location.
2694 
2695    Does not handle issues such as token lookahead, multiple-include
2696    optimization, directives, skipping etc.  This function is only
2697    suitable for use by _cpp_lex_token, and in special cases like
2698    lex_expansion_token which doesn't care for any of these issues.
2699 
2700    When meeting a newline, returns CPP_EOF if parsing a directive,
2701    otherwise returns to the start of the token buffer if permissible.
2702    Returns the location of the lexed token.  */
2703 cpp_token *
2704 _cpp_lex_direct (cpp_reader *pfile)
2705 {
2706   cppchar_t c;
2707   cpp_buffer *buffer;
2708   const unsigned char *comment_start;
2709   bool fallthrough_comment = false;
2710   cpp_token *result = pfile->cur_token++;
2711 
2712  fresh_line:
2713   result->flags = 0;
2714   buffer = pfile->buffer;
2715   if (buffer->need_line)
2716     {
2717       if (pfile->state.in_deferred_pragma)
2718 	{
2719 	  result->type = CPP_PRAGMA_EOL;
2720 	  pfile->state.in_deferred_pragma = false;
2721 	  if (!pfile->state.pragma_allow_expansion)
2722 	    pfile->state.prevent_expansion--;
2723 	  return result;
2724 	}
2725       if (!_cpp_get_fresh_line (pfile))
2726 	{
2727 	  result->type = CPP_EOF;
2728 	  if (!pfile->state.in_directive)
2729 	    {
2730 	      /* Tell the compiler the line number of the EOF token.  */
2731 	      result->src_loc = pfile->line_table->highest_line;
2732 	      result->flags = BOL;
2733 	    }
2734 	  return result;
2735 	}
2736       if (buffer != pfile->buffer)
2737 	fallthrough_comment = false;
2738       if (!pfile->keep_tokens)
2739 	{
2740 	  pfile->cur_run = &pfile->base_run;
2741 	  result = pfile->base_run.base;
2742 	  pfile->cur_token = result + 1;
2743 	}
2744       result->flags = BOL;
2745       if (pfile->state.parsing_args == 2)
2746 	result->flags |= PREV_WHITE;
2747     }
2748   buffer = pfile->buffer;
2749  update_tokens_line:
2750   result->src_loc = pfile->line_table->highest_line;
2751 
2752  skipped_white:
2753   if (buffer->cur >= buffer->notes[buffer->cur_note].pos
2754       && !pfile->overlaid_buffer)
2755     {
2756       _cpp_process_line_notes (pfile, false);
2757       result->src_loc = pfile->line_table->highest_line;
2758     }
2759   c = *buffer->cur++;
2760 
2761   if (pfile->forced_token_location)
2762     result->src_loc = pfile->forced_token_location;
2763   else
2764     result->src_loc = linemap_position_for_column (pfile->line_table,
2765 					  CPP_BUF_COLUMN (buffer, buffer->cur));
2766 
2767   switch (c)
2768     {
2769     case ' ': case '\t': case '\f': case '\v': case '\0':
2770       result->flags |= PREV_WHITE;
2771       skip_whitespace (pfile, c);
2772       goto skipped_white;
2773 
2774     case '\n':
2775       if (buffer->cur < buffer->rlimit)
2776 	CPP_INCREMENT_LINE (pfile, 0);
2777       buffer->need_line = true;
2778       goto fresh_line;
2779 
2780     case '0': case '1': case '2': case '3': case '4':
2781     case '5': case '6': case '7': case '8': case '9':
2782       {
2783 	struct normalize_state nst = INITIAL_NORMALIZE_STATE;
2784 	result->type = CPP_NUMBER;
2785 	lex_number (pfile, &result->val.str, &nst);
2786 	warn_about_normalization (pfile, result, &nst);
2787 	break;
2788       }
2789 
2790     case 'L':
2791     case 'u':
2792     case 'U':
2793     case 'R':
2794       /* 'L', 'u', 'U', 'u8' or 'R' may introduce wide characters,
2795 	 wide strings or raw strings.  */
2796       if (c == 'L' || CPP_OPTION (pfile, rliterals)
2797 	  || (c != 'R' && CPP_OPTION (pfile, uliterals)))
2798 	{
2799 	  if ((*buffer->cur == '\'' && c != 'R')
2800 	      || *buffer->cur == '"'
2801 	      || (*buffer->cur == 'R'
2802 		  && c != 'R'
2803 		  && buffer->cur[1] == '"'
2804 		  && CPP_OPTION (pfile, rliterals))
2805 	      || (*buffer->cur == '8'
2806 		  && c == 'u'
2807 		  && ((buffer->cur[1] == '"' || (buffer->cur[1] == '\''
2808 				&& CPP_OPTION (pfile, utf8_char_literals)))
2809 		      || (buffer->cur[1] == 'R' && buffer->cur[2] == '"'
2810 			  && CPP_OPTION (pfile, rliterals)))))
2811 	    {
2812 	      lex_string (pfile, result, buffer->cur - 1);
2813 	      break;
2814 	    }
2815 	}
2816       /* Fall through.  */
2817 
2818     case '_':
2819     case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
2820     case 'g': case 'h': case 'i': case 'j': case 'k': case 'l':
2821     case 'm': case 'n': case 'o': case 'p': case 'q': case 'r':
2822     case 's': case 't':           case 'v': case 'w': case 'x':
2823     case 'y': case 'z':
2824     case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
2825     case 'G': case 'H': case 'I': case 'J': case 'K':
2826     case 'M': case 'N': case 'O': case 'P': case 'Q':
2827     case 'S': case 'T':           case 'V': case 'W': case 'X':
2828     case 'Y': case 'Z':
2829       result->type = CPP_NAME;
2830       {
2831 	struct normalize_state nst = INITIAL_NORMALIZE_STATE;
2832 	result->val.node.node = lex_identifier (pfile, buffer->cur - 1, false,
2833 						&nst,
2834 						&result->val.node.spelling);
2835 	warn_about_normalization (pfile, result, &nst);
2836       }
2837 
2838       /* Convert named operators to their proper types.  */
2839       if (result->val.node.node->flags & NODE_OPERATOR)
2840 	{
2841 	  result->flags |= NAMED_OP;
2842 	  result->type = (enum cpp_ttype) result->val.node.node->directive_index;
2843 	}
2844 
2845       /* Signal FALLTHROUGH comment followed by another token.  */
2846       if (fallthrough_comment)
2847 	result->flags |= PREV_FALLTHROUGH;
2848       break;
2849 
2850     case '\'':
2851     case '"':
2852       lex_string (pfile, result, buffer->cur - 1);
2853       break;
2854 
2855     case '/':
2856       /* A potential block or line comment.  */
2857       comment_start = buffer->cur;
2858       c = *buffer->cur;
2859 
2860       if (c == '*')
2861 	{
2862 	  if (_cpp_skip_block_comment (pfile))
2863 	    cpp_error (pfile, CPP_DL_ERROR, "unterminated comment");
2864 	}
2865       else if (c == '/' && ! CPP_OPTION (pfile, traditional))
2866 	{
2867 	  /* Don't warn for system headers.  */
2868 	  if (cpp_in_system_header (pfile))
2869 	    ;
2870 	  /* Warn about comments if pedantically GNUC89, and not
2871 	     in system headers.  */
2872 	  else if (CPP_OPTION (pfile, lang) == CLK_GNUC89
2873 		   && CPP_PEDANTIC (pfile)
2874 		   && ! buffer->warned_cplusplus_comments)
2875 	    {
2876 	      if (cpp_error (pfile, CPP_DL_PEDWARN,
2877 			     "C++ style comments are not allowed in ISO C90"))
2878 		cpp_error (pfile, CPP_DL_NOTE,
2879 			   "(this will be reported only once per input file)");
2880 	      buffer->warned_cplusplus_comments = 1;
2881 	    }
2882 	  /* Or if specifically desired via -Wc90-c99-compat.  */
2883 	  else if (CPP_OPTION (pfile, cpp_warn_c90_c99_compat) > 0
2884 		   && ! CPP_OPTION (pfile, cplusplus)
2885 		   && ! buffer->warned_cplusplus_comments)
2886 	    {
2887 	      if (cpp_error (pfile, CPP_DL_WARNING,
2888 			     "C++ style comments are incompatible with C90"))
2889 		cpp_error (pfile, CPP_DL_NOTE,
2890 			   "(this will be reported only once per input file)");
2891 	      buffer->warned_cplusplus_comments = 1;
2892 	    }
2893 	  /* In C89/C94, C++ style comments are forbidden.  */
2894 	  else if ((CPP_OPTION (pfile, lang) == CLK_STDC89
2895 		    || CPP_OPTION (pfile, lang) == CLK_STDC94))
2896 	    {
2897 	      /* But don't be confused about valid code such as
2898 	         - // immediately followed by *,
2899 		 - // in a preprocessing directive,
2900 		 - // in an #if 0 block.  */
2901 	      if (buffer->cur[1] == '*'
2902 		  || pfile->state.in_directive
2903 		  || pfile->state.skipping)
2904 		{
2905 		  result->type = CPP_DIV;
2906 		  break;
2907 		}
2908 	      else if (! buffer->warned_cplusplus_comments)
2909 		{
2910 		  if (cpp_error (pfile, CPP_DL_ERROR,
2911 				 "C++ style comments are not allowed in "
2912 				 "ISO C90"))
2913 		    cpp_error (pfile, CPP_DL_NOTE,
2914 			       "(this will be reported only once per input "
2915 			       "file)");
2916 		  buffer->warned_cplusplus_comments = 1;
2917 		}
2918 	    }
2919 	  if (skip_line_comment (pfile) && CPP_OPTION (pfile, warn_comments))
2920 	    cpp_warning (pfile, CPP_W_COMMENTS, "multi-line comment");
2921 	}
2922       else if (c == '=')
2923 	{
2924 	  buffer->cur++;
2925 	  result->type = CPP_DIV_EQ;
2926 	  break;
2927 	}
2928       else
2929 	{
2930 	  result->type = CPP_DIV;
2931 	  break;
2932 	}
2933 
2934       if (fallthrough_comment_p (pfile, comment_start))
2935 	fallthrough_comment = true;
2936 
2937       if (pfile->cb.comment)
2938 	{
2939 	  size_t len = pfile->buffer->cur - comment_start;
2940 	  pfile->cb.comment (pfile, result->src_loc, comment_start - 1,
2941 			     len + 1);
2942 	}
2943 
2944       if (!pfile->state.save_comments)
2945 	{
2946 	  result->flags |= PREV_WHITE;
2947 	  goto update_tokens_line;
2948 	}
2949 
2950       if (fallthrough_comment)
2951 	result->flags |= PREV_FALLTHROUGH;
2952 
2953       /* Save the comment as a token in its own right.  */
2954       save_comment (pfile, result, comment_start, c);
2955       break;
2956 
2957     case '<':
2958       if (pfile->state.angled_headers)
2959 	{
2960 	  lex_string (pfile, result, buffer->cur - 1);
2961 	  if (result->type != CPP_LESS)
2962 	    break;
2963 	}
2964 
2965       result->type = CPP_LESS;
2966       if (*buffer->cur == '=')
2967 	buffer->cur++, result->type = CPP_LESS_EQ;
2968       else if (*buffer->cur == '<')
2969 	{
2970 	  buffer->cur++;
2971 	  IF_NEXT_IS ('=', CPP_LSHIFT_EQ, CPP_LSHIFT);
2972 	}
2973       else if (CPP_OPTION (pfile, digraphs))
2974 	{
2975 	  if (*buffer->cur == ':')
2976 	    {
2977 	      /* C++11 [2.5/3 lex.pptoken], "Otherwise, if the next
2978 		 three characters are <:: and the subsequent character
2979 		 is neither : nor >, the < is treated as a preprocessor
2980 		 token by itself".  */
2981 	      if (CPP_OPTION (pfile, cplusplus)
2982 		  && CPP_OPTION (pfile, lang) != CLK_CXX98
2983 		  && CPP_OPTION (pfile, lang) != CLK_GNUCXX
2984 		  && buffer->cur[1] == ':'
2985 		  && buffer->cur[2] != ':' && buffer->cur[2] != '>')
2986 		break;
2987 
2988 	      buffer->cur++;
2989 	      result->flags |= DIGRAPH;
2990 	      result->type = CPP_OPEN_SQUARE;
2991 	    }
2992 	  else if (*buffer->cur == '%')
2993 	    {
2994 	      buffer->cur++;
2995 	      result->flags |= DIGRAPH;
2996 	      result->type = CPP_OPEN_BRACE;
2997 	    }
2998 	}
2999       break;
3000 
3001     case '>':
3002       result->type = CPP_GREATER;
3003       if (*buffer->cur == '=')
3004 	buffer->cur++, result->type = CPP_GREATER_EQ;
3005       else if (*buffer->cur == '>')
3006 	{
3007 	  buffer->cur++;
3008 	  IF_NEXT_IS ('=', CPP_RSHIFT_EQ, CPP_RSHIFT);
3009 	}
3010       break;
3011 
3012     case '%':
3013       result->type = CPP_MOD;
3014       if (*buffer->cur == '=')
3015 	buffer->cur++, result->type = CPP_MOD_EQ;
3016       else if (CPP_OPTION (pfile, digraphs))
3017 	{
3018 	  if (*buffer->cur == ':')
3019 	    {
3020 	      buffer->cur++;
3021 	      result->flags |= DIGRAPH;
3022 	      result->type = CPP_HASH;
3023 	      if (*buffer->cur == '%' && buffer->cur[1] == ':')
3024 		buffer->cur += 2, result->type = CPP_PASTE, result->val.token_no = 0;
3025 	    }
3026 	  else if (*buffer->cur == '>')
3027 	    {
3028 	      buffer->cur++;
3029 	      result->flags |= DIGRAPH;
3030 	      result->type = CPP_CLOSE_BRACE;
3031 	    }
3032 	}
3033       break;
3034 
3035     case '.':
3036       result->type = CPP_DOT;
3037       if (ISDIGIT (*buffer->cur))
3038 	{
3039 	  struct normalize_state nst = INITIAL_NORMALIZE_STATE;
3040 	  result->type = CPP_NUMBER;
3041 	  lex_number (pfile, &result->val.str, &nst);
3042 	  warn_about_normalization (pfile, result, &nst);
3043 	}
3044       else if (*buffer->cur == '.' && buffer->cur[1] == '.')
3045 	buffer->cur += 2, result->type = CPP_ELLIPSIS;
3046       else if (*buffer->cur == '*' && CPP_OPTION (pfile, cplusplus))
3047 	buffer->cur++, result->type = CPP_DOT_STAR;
3048       break;
3049 
3050     case '+':
3051       result->type = CPP_PLUS;
3052       if (*buffer->cur == '+')
3053 	buffer->cur++, result->type = CPP_PLUS_PLUS;
3054       else if (*buffer->cur == '=')
3055 	buffer->cur++, result->type = CPP_PLUS_EQ;
3056       break;
3057 
3058     case '-':
3059       result->type = CPP_MINUS;
3060       if (*buffer->cur == '>')
3061 	{
3062 	  buffer->cur++;
3063 	  result->type = CPP_DEREF;
3064 	  if (*buffer->cur == '*' && CPP_OPTION (pfile, cplusplus))
3065 	    buffer->cur++, result->type = CPP_DEREF_STAR;
3066 	}
3067       else if (*buffer->cur == '-')
3068 	buffer->cur++, result->type = CPP_MINUS_MINUS;
3069       else if (*buffer->cur == '=')
3070 	buffer->cur++, result->type = CPP_MINUS_EQ;
3071       break;
3072 
3073     case '&':
3074       result->type = CPP_AND;
3075       if (*buffer->cur == '&')
3076 	buffer->cur++, result->type = CPP_AND_AND;
3077       else if (*buffer->cur == '=')
3078 	buffer->cur++, result->type = CPP_AND_EQ;
3079       break;
3080 
3081     case '|':
3082       result->type = CPP_OR;
3083       if (*buffer->cur == '|')
3084 	buffer->cur++, result->type = CPP_OR_OR;
3085       else if (*buffer->cur == '=')
3086 	buffer->cur++, result->type = CPP_OR_EQ;
3087       break;
3088 
3089     case ':':
3090       result->type = CPP_COLON;
3091       if (*buffer->cur == ':' && CPP_OPTION (pfile, cplusplus))
3092 	buffer->cur++, result->type = CPP_SCOPE;
3093       else if (*buffer->cur == '>' && CPP_OPTION (pfile, digraphs))
3094 	{
3095 	  buffer->cur++;
3096 	  result->flags |= DIGRAPH;
3097 	  result->type = CPP_CLOSE_SQUARE;
3098 	}
3099       break;
3100 
3101     case '*': IF_NEXT_IS ('=', CPP_MULT_EQ, CPP_MULT); break;
3102     case '=': IF_NEXT_IS ('=', CPP_EQ_EQ, CPP_EQ); break;
3103     case '!': IF_NEXT_IS ('=', CPP_NOT_EQ, CPP_NOT); break;
3104     case '^': IF_NEXT_IS ('=', CPP_XOR_EQ, CPP_XOR); break;
3105     case '#': IF_NEXT_IS ('#', CPP_PASTE, CPP_HASH); result->val.token_no = 0; break;
3106 
3107     case '?': result->type = CPP_QUERY; break;
3108     case '~': result->type = CPP_COMPL; break;
3109     case ',': result->type = CPP_COMMA; break;
3110     case '(': result->type = CPP_OPEN_PAREN; break;
3111     case ')': result->type = CPP_CLOSE_PAREN; break;
3112     case '[': result->type = CPP_OPEN_SQUARE; break;
3113     case ']': result->type = CPP_CLOSE_SQUARE; break;
3114     case '{': result->type = CPP_OPEN_BRACE; break;
3115     case '}': result->type = CPP_CLOSE_BRACE; break;
3116     case ';': result->type = CPP_SEMICOLON; break;
3117 
3118       /* @ is a punctuator in Objective-C.  */
3119     case '@': result->type = CPP_ATSIGN; break;
3120 
3121     case '$':
3122     case '\\':
3123       {
3124 	const uchar *base = --buffer->cur;
3125 	struct normalize_state nst = INITIAL_NORMALIZE_STATE;
3126 
3127 	if (forms_identifier_p (pfile, true, &nst))
3128 	  {
3129 	    result->type = CPP_NAME;
3130 	    result->val.node.node = lex_identifier (pfile, base, true, &nst,
3131 						    &result->val.node.spelling);
3132 	    warn_about_normalization (pfile, result, &nst);
3133 	    break;
3134 	  }
3135 	buffer->cur++;
3136       }
3137       /* FALLTHRU */
3138 
3139     default:
3140       create_literal (pfile, result, buffer->cur - 1, 1, CPP_OTHER);
3141       break;
3142     }
3143 
3144   /* Potentially convert the location of the token to a range.  */
3145   if (result->src_loc >= RESERVED_LOCATION_COUNT
3146       && result->type != CPP_EOF)
3147     {
3148       /* Ensure that any line notes are processed, so that we have the
3149 	 correct physical line/column for the end-point of the token even
3150 	 when a logical line is split via one or more backslashes.  */
3151       if (buffer->cur >= buffer->notes[buffer->cur_note].pos
3152 	  && !pfile->overlaid_buffer)
3153 	_cpp_process_line_notes (pfile, false);
3154 
3155       source_range tok_range;
3156       tok_range.m_start = result->src_loc;
3157       tok_range.m_finish
3158 	= linemap_position_for_column (pfile->line_table,
3159 				       CPP_BUF_COLUMN (buffer, buffer->cur));
3160 
3161       result->src_loc = COMBINE_LOCATION_DATA (pfile->line_table,
3162 					       result->src_loc,
3163 					       tok_range, NULL);
3164     }
3165 
3166   return result;
3167 }
3168 
3169 /* An upper bound on the number of bytes needed to spell TOKEN.
3170    Does not include preceding whitespace.  */
3171 unsigned int
3172 cpp_token_len (const cpp_token *token)
3173 {
3174   unsigned int len;
3175 
3176   switch (TOKEN_SPELL (token))
3177     {
3178     default:		len = 6;				break;
3179     case SPELL_LITERAL:	len = token->val.str.len;		break;
3180     case SPELL_IDENT:	len = NODE_LEN (token->val.node.node) * 10;	break;
3181     }
3182 
3183   return len;
3184 }
3185 
3186 /* Parse UTF-8 out of NAMEP and place a \U escape in BUFFER.
3187    Return the number of bytes read out of NAME.  (There are always
3188    10 bytes written to BUFFER.)  */
3189 
3190 static size_t
3191 utf8_to_ucn (unsigned char *buffer, const unsigned char *name)
3192 {
3193   int j;
3194   int ucn_len = 0;
3195   int ucn_len_c;
3196   unsigned t;
3197   unsigned long utf32;
3198 
3199   /* Compute the length of the UTF-8 sequence.  */
3200   for (t = *name; t & 0x80; t <<= 1)
3201     ucn_len++;
3202 
3203   utf32 = *name & (0x7F >> ucn_len);
3204   for (ucn_len_c = 1; ucn_len_c < ucn_len; ucn_len_c++)
3205     {
3206       utf32 = (utf32 << 6) | (*++name & 0x3F);
3207 
3208       /* Ill-formed UTF-8.  */
3209       if ((*name & ~0x3F) != 0x80)
3210 	abort ();
3211     }
3212 
3213   *buffer++ = '\\';
3214   *buffer++ = 'U';
3215   for (j = 7; j >= 0; j--)
3216     *buffer++ = "0123456789abcdef"[(utf32 >> (4 * j)) & 0xF];
3217   return ucn_len;
3218 }
3219 
3220 /* Given a token TYPE corresponding to a digraph, return a pointer to
3221    the spelling of the digraph.  */
3222 static const unsigned char *
3223 cpp_digraph2name (enum cpp_ttype type)
3224 {
3225   return digraph_spellings[(int) type - (int) CPP_FIRST_DIGRAPH];
3226 }
3227 
3228 /* Write the spelling of an identifier IDENT, using UCNs, to BUFFER.
3229    The buffer must already contain the enough space to hold the
3230    token's spelling.  Returns a pointer to the character after the
3231    last character written.  */
3232 unsigned char *
3233 _cpp_spell_ident_ucns (unsigned char *buffer, cpp_hashnode *ident)
3234 {
3235   size_t i;
3236   const unsigned char *name = NODE_NAME (ident);
3237 
3238   for (i = 0; i < NODE_LEN (ident); i++)
3239     if (name[i] & ~0x7F)
3240       {
3241 	i += utf8_to_ucn (buffer, name + i) - 1;
3242 	buffer += 10;
3243       }
3244     else
3245       *buffer++ = name[i];
3246 
3247   return buffer;
3248 }
3249 
3250 /* Write the spelling of a token TOKEN to BUFFER.  The buffer must
3251    already contain the enough space to hold the token's spelling.
3252    Returns a pointer to the character after the last character written.
3253    FORSTRING is true if this is to be the spelling after translation
3254    phase 1 (with the original spelling of extended identifiers), false
3255    if extended identifiers should always be written using UCNs (there is
3256    no option for always writing them in the internal UTF-8 form).
3257    FIXME: Would be nice if we didn't need the PFILE argument.  */
3258 unsigned char *
3259 cpp_spell_token (cpp_reader *pfile, const cpp_token *token,
3260 		 unsigned char *buffer, bool forstring)
3261 {
3262   switch (TOKEN_SPELL (token))
3263     {
3264     case SPELL_OPERATOR:
3265       {
3266 	const unsigned char *spelling;
3267 	unsigned char c;
3268 
3269 	if (token->flags & DIGRAPH)
3270 	  spelling = cpp_digraph2name (token->type);
3271 	else if (token->flags & NAMED_OP)
3272 	  goto spell_ident;
3273 	else
3274 	  spelling = TOKEN_NAME (token);
3275 
3276 	while ((c = *spelling++) != '\0')
3277 	  *buffer++ = c;
3278       }
3279       break;
3280 
3281     spell_ident:
3282     case SPELL_IDENT:
3283       if (forstring)
3284 	{
3285 	  memcpy (buffer, NODE_NAME (token->val.node.spelling),
3286 		  NODE_LEN (token->val.node.spelling));
3287 	  buffer += NODE_LEN (token->val.node.spelling);
3288 	}
3289       else
3290 	buffer = _cpp_spell_ident_ucns (buffer, token->val.node.node);
3291       break;
3292 
3293     case SPELL_LITERAL:
3294       memcpy (buffer, token->val.str.text, token->val.str.len);
3295       buffer += token->val.str.len;
3296       break;
3297 
3298     case SPELL_NONE:
3299       cpp_error (pfile, CPP_DL_ICE,
3300 		 "unspellable token %s", TOKEN_NAME (token));
3301       break;
3302     }
3303 
3304   return buffer;
3305 }
3306 
3307 /* Returns TOKEN spelt as a null-terminated string.  The string is
3308    freed when the reader is destroyed.  Useful for diagnostics.  */
3309 unsigned char *
3310 cpp_token_as_text (cpp_reader *pfile, const cpp_token *token)
3311 {
3312   unsigned int len = cpp_token_len (token) + 1;
3313   unsigned char *start = _cpp_unaligned_alloc (pfile, len), *end;
3314 
3315   end = cpp_spell_token (pfile, token, start, false);
3316   end[0] = '\0';
3317 
3318   return start;
3319 }
3320 
3321 /* Returns a pointer to a string which spells the token defined by
3322    TYPE and FLAGS.  Used by C front ends, which really should move to
3323    using cpp_token_as_text.  */
3324 const char *
3325 cpp_type2name (enum cpp_ttype type, unsigned char flags)
3326 {
3327   if (flags & DIGRAPH)
3328     return (const char *) cpp_digraph2name (type);
3329   else if (flags & NAMED_OP)
3330     return cpp_named_operator2name (type);
3331 
3332   return (const char *) token_spellings[type].name;
3333 }
3334 
3335 /* Writes the spelling of token to FP, without any preceding space.
3336    Separated from cpp_spell_token for efficiency - to avoid stdio
3337    double-buffering.  */
3338 void
3339 cpp_output_token (const cpp_token *token, FILE *fp)
3340 {
3341   switch (TOKEN_SPELL (token))
3342     {
3343     case SPELL_OPERATOR:
3344       {
3345 	const unsigned char *spelling;
3346 	int c;
3347 
3348 	if (token->flags & DIGRAPH)
3349 	  spelling = cpp_digraph2name (token->type);
3350 	else if (token->flags & NAMED_OP)
3351 	  goto spell_ident;
3352 	else
3353 	  spelling = TOKEN_NAME (token);
3354 
3355 	c = *spelling;
3356 	do
3357 	  putc (c, fp);
3358 	while ((c = *++spelling) != '\0');
3359       }
3360       break;
3361 
3362     spell_ident:
3363     case SPELL_IDENT:
3364       {
3365 	size_t i;
3366 	const unsigned char * name = NODE_NAME (token->val.node.node);
3367 
3368 	for (i = 0; i < NODE_LEN (token->val.node.node); i++)
3369 	  if (name[i] & ~0x7F)
3370 	    {
3371 	      unsigned char buffer[10];
3372 	      i += utf8_to_ucn (buffer, name + i) - 1;
3373 	      fwrite (buffer, 1, 10, fp);
3374 	    }
3375 	  else
3376 	    fputc (NODE_NAME (token->val.node.node)[i], fp);
3377       }
3378       break;
3379 
3380     case SPELL_LITERAL:
3381       fwrite (token->val.str.text, 1, token->val.str.len, fp);
3382       break;
3383 
3384     case SPELL_NONE:
3385       /* An error, most probably.  */
3386       break;
3387     }
3388 }
3389 
3390 /* Compare two tokens.  */
3391 int
3392 _cpp_equiv_tokens (const cpp_token *a, const cpp_token *b)
3393 {
3394   if (a->type == b->type && a->flags == b->flags)
3395     switch (TOKEN_SPELL (a))
3396       {
3397       default:			/* Keep compiler happy.  */
3398       case SPELL_OPERATOR:
3399 	/* token_no is used to track where multiple consecutive ##
3400 	   tokens were originally located.  */
3401 	return (a->type != CPP_PASTE || a->val.token_no == b->val.token_no);
3402       case SPELL_NONE:
3403 	return (a->type != CPP_MACRO_ARG
3404 		|| (a->val.macro_arg.arg_no == b->val.macro_arg.arg_no
3405 		    && a->val.macro_arg.spelling == b->val.macro_arg.spelling));
3406       case SPELL_IDENT:
3407 	return (a->val.node.node == b->val.node.node
3408 		&& a->val.node.spelling == b->val.node.spelling);
3409       case SPELL_LITERAL:
3410 	return (a->val.str.len == b->val.str.len
3411 		&& !memcmp (a->val.str.text, b->val.str.text,
3412 			    a->val.str.len));
3413       }
3414 
3415   return 0;
3416 }
3417 
3418 /* Returns nonzero if a space should be inserted to avoid an
3419    accidental token paste for output.  For simplicity, it is
3420    conservative, and occasionally advises a space where one is not
3421    needed, e.g. "." and ".2".  */
3422 int
3423 cpp_avoid_paste (cpp_reader *pfile, const cpp_token *token1,
3424 		 const cpp_token *token2)
3425 {
3426   enum cpp_ttype a = token1->type, b = token2->type;
3427   cppchar_t c;
3428 
3429   if (token1->flags & NAMED_OP)
3430     a = CPP_NAME;
3431   if (token2->flags & NAMED_OP)
3432     b = CPP_NAME;
3433 
3434   c = EOF;
3435   if (token2->flags & DIGRAPH)
3436     c = digraph_spellings[(int) b - (int) CPP_FIRST_DIGRAPH][0];
3437   else if (token_spellings[b].category == SPELL_OPERATOR)
3438     c = token_spellings[b].name[0];
3439 
3440   /* Quickly get everything that can paste with an '='.  */
3441   if ((int) a <= (int) CPP_LAST_EQ && c == '=')
3442     return 1;
3443 
3444   switch (a)
3445     {
3446     case CPP_GREATER:	return c == '>';
3447     case CPP_LESS:	return c == '<' || c == '%' || c == ':';
3448     case CPP_PLUS:	return c == '+';
3449     case CPP_MINUS:	return c == '-' || c == '>';
3450     case CPP_DIV:	return c == '/' || c == '*'; /* Comments.  */
3451     case CPP_MOD:	return c == ':' || c == '>';
3452     case CPP_AND:	return c == '&';
3453     case CPP_OR:	return c == '|';
3454     case CPP_COLON:	return c == ':' || c == '>';
3455     case CPP_DEREF:	return c == '*';
3456     case CPP_DOT:	return c == '.' || c == '%' || b == CPP_NUMBER;
3457     case CPP_HASH:	return c == '#' || c == '%'; /* Digraph form.  */
3458     case CPP_NAME:	return ((b == CPP_NUMBER
3459 				 && name_p (pfile, &token2->val.str))
3460 				|| b == CPP_NAME
3461 				|| b == CPP_CHAR || b == CPP_STRING); /* L */
3462     case CPP_NUMBER:	return (b == CPP_NUMBER || b == CPP_NAME
3463 				|| c == '.' || c == '+' || c == '-');
3464 				      /* UCNs */
3465     case CPP_OTHER:	return ((token1->val.str.text[0] == '\\'
3466 				 && b == CPP_NAME)
3467 				|| (CPP_OPTION (pfile, objc)
3468 				    && token1->val.str.text[0] == '@'
3469 				    && (b == CPP_NAME || b == CPP_STRING)));
3470     case CPP_STRING:
3471     case CPP_WSTRING:
3472     case CPP_UTF8STRING:
3473     case CPP_STRING16:
3474     case CPP_STRING32:	return (CPP_OPTION (pfile, user_literals)
3475 				&& (b == CPP_NAME
3476 				    || (TOKEN_SPELL (token2) == SPELL_LITERAL
3477 					&& ISIDST (token2->val.str.text[0]))));
3478 
3479     default:		break;
3480     }
3481 
3482   return 0;
3483 }
3484 
3485 /* Output all the remaining tokens on the current line, and a newline
3486    character, to FP.  Leading whitespace is removed.  If there are
3487    macros, special token padding is not performed.  */
3488 void
3489 cpp_output_line (cpp_reader *pfile, FILE *fp)
3490 {
3491   const cpp_token *token;
3492 
3493   token = cpp_get_token (pfile);
3494   while (token->type != CPP_EOF)
3495     {
3496       cpp_output_token (token, fp);
3497       token = cpp_get_token (pfile);
3498       if (token->flags & PREV_WHITE)
3499 	putc (' ', fp);
3500     }
3501 
3502   putc ('\n', fp);
3503 }
3504 
3505 /* Return a string representation of all the remaining tokens on the
3506    current line.  The result is allocated using xmalloc and must be
3507    freed by the caller.  */
3508 unsigned char *
3509 cpp_output_line_to_string (cpp_reader *pfile, const unsigned char *dir_name)
3510 {
3511   const cpp_token *token;
3512   unsigned int out = dir_name ? ustrlen (dir_name) : 0;
3513   unsigned int alloced = 120 + out;
3514   unsigned char *result = (unsigned char *) xmalloc (alloced);
3515 
3516   /* If DIR_NAME is empty, there are no initial contents.  */
3517   if (dir_name)
3518     {
3519       sprintf ((char *) result, "#%s ", dir_name);
3520       out += 2;
3521     }
3522 
3523   token = cpp_get_token (pfile);
3524   while (token->type != CPP_EOF)
3525     {
3526       unsigned char *last;
3527       /* Include room for a possible space and the terminating nul.  */
3528       unsigned int len = cpp_token_len (token) + 2;
3529 
3530       if (out + len > alloced)
3531 	{
3532 	  alloced *= 2;
3533 	  if (out + len > alloced)
3534 	    alloced = out + len;
3535 	  result = (unsigned char *) xrealloc (result, alloced);
3536 	}
3537 
3538       last = cpp_spell_token (pfile, token, &result[out], 0);
3539       out = last - result;
3540 
3541       token = cpp_get_token (pfile);
3542       if (token->flags & PREV_WHITE)
3543 	result[out++] = ' ';
3544     }
3545 
3546   result[out] = '\0';
3547   return result;
3548 }
3549 
3550 /* Memory buffers.  Changing these three constants can have a dramatic
3551    effect on performance.  The values here are reasonable defaults,
3552    but might be tuned.  If you adjust them, be sure to test across a
3553    range of uses of cpplib, including heavy nested function-like macro
3554    expansion.  Also check the change in peak memory usage (NJAMD is a
3555    good tool for this).  */
3556 #define MIN_BUFF_SIZE 8000
3557 #define BUFF_SIZE_UPPER_BOUND(MIN_SIZE) (MIN_BUFF_SIZE + (MIN_SIZE) * 3 / 2)
3558 #define EXTENDED_BUFF_SIZE(BUFF, MIN_EXTRA) \
3559 	(MIN_EXTRA + ((BUFF)->limit - (BUFF)->cur) * 2)
3560 
3561 #if MIN_BUFF_SIZE > BUFF_SIZE_UPPER_BOUND (0)
3562   #error BUFF_SIZE_UPPER_BOUND must be at least as large as MIN_BUFF_SIZE!
3563 #endif
3564 
3565 /* Create a new allocation buffer.  Place the control block at the end
3566    of the buffer, so that buffer overflows will cause immediate chaos.  */
3567 static _cpp_buff *
3568 new_buff (size_t len)
3569 {
3570   _cpp_buff *result;
3571   unsigned char *base;
3572 
3573   if (len < MIN_BUFF_SIZE)
3574     len = MIN_BUFF_SIZE;
3575   len = CPP_ALIGN (len);
3576 
3577 #ifdef ENABLE_VALGRIND_ANNOTATIONS
3578   /* Valgrind warns about uses of interior pointers, so put _cpp_buff
3579      struct first.  */
3580   size_t slen = CPP_ALIGN2 (sizeof (_cpp_buff), 2 * DEFAULT_ALIGNMENT);
3581   base = XNEWVEC (unsigned char, len + slen);
3582   result = (_cpp_buff *) base;
3583   base += slen;
3584 #else
3585   base = XNEWVEC (unsigned char, len + sizeof (_cpp_buff));
3586   result = (_cpp_buff *) (base + len);
3587 #endif
3588   result->base = base;
3589   result->cur = base;
3590   result->limit = base + len;
3591   result->next = NULL;
3592   return result;
3593 }
3594 
3595 /* Place a chain of unwanted allocation buffers on the free list.  */
3596 void
3597 _cpp_release_buff (cpp_reader *pfile, _cpp_buff *buff)
3598 {
3599   _cpp_buff *end = buff;
3600 
3601   while (end->next)
3602     end = end->next;
3603   end->next = pfile->free_buffs;
3604   pfile->free_buffs = buff;
3605 }
3606 
3607 /* Return a free buffer of size at least MIN_SIZE.  */
3608 _cpp_buff *
3609 _cpp_get_buff (cpp_reader *pfile, size_t min_size)
3610 {
3611   _cpp_buff *result, **p;
3612 
3613   for (p = &pfile->free_buffs;; p = &(*p)->next)
3614     {
3615       size_t size;
3616 
3617       if (*p == NULL)
3618 	return new_buff (min_size);
3619       result = *p;
3620       size = result->limit - result->base;
3621       /* Return a buffer that's big enough, but don't waste one that's
3622          way too big.  */
3623       if (size >= min_size && size <= BUFF_SIZE_UPPER_BOUND (min_size))
3624 	break;
3625     }
3626 
3627   *p = result->next;
3628   result->next = NULL;
3629   result->cur = result->base;
3630   return result;
3631 }
3632 
3633 /* Creates a new buffer with enough space to hold the uncommitted
3634    remaining bytes of BUFF, and at least MIN_EXTRA more bytes.  Copies
3635    the excess bytes to the new buffer.  Chains the new buffer after
3636    BUFF, and returns the new buffer.  */
3637 _cpp_buff *
3638 _cpp_append_extend_buff (cpp_reader *pfile, _cpp_buff *buff, size_t min_extra)
3639 {
3640   size_t size = EXTENDED_BUFF_SIZE (buff, min_extra);
3641   _cpp_buff *new_buff = _cpp_get_buff (pfile, size);
3642 
3643   buff->next = new_buff;
3644   memcpy (new_buff->base, buff->cur, BUFF_ROOM (buff));
3645   return new_buff;
3646 }
3647 
3648 /* Creates a new buffer with enough space to hold the uncommitted
3649    remaining bytes of the buffer pointed to by BUFF, and at least
3650    MIN_EXTRA more bytes.  Copies the excess bytes to the new buffer.
3651    Chains the new buffer before the buffer pointed to by BUFF, and
3652    updates the pointer to point to the new buffer.  */
3653 void
3654 _cpp_extend_buff (cpp_reader *pfile, _cpp_buff **pbuff, size_t min_extra)
3655 {
3656   _cpp_buff *new_buff, *old_buff = *pbuff;
3657   size_t size = EXTENDED_BUFF_SIZE (old_buff, min_extra);
3658 
3659   new_buff = _cpp_get_buff (pfile, size);
3660   memcpy (new_buff->base, old_buff->cur, BUFF_ROOM (old_buff));
3661   new_buff->next = old_buff;
3662   *pbuff = new_buff;
3663 }
3664 
3665 /* Free a chain of buffers starting at BUFF.  */
3666 void
3667 _cpp_free_buff (_cpp_buff *buff)
3668 {
3669   _cpp_buff *next;
3670 
3671   for (; buff; buff = next)
3672     {
3673       next = buff->next;
3674 #ifdef ENABLE_VALGRIND_ANNOTATIONS
3675       free (buff);
3676 #else
3677       free (buff->base);
3678 #endif
3679     }
3680 }
3681 
3682 /* Allocate permanent, unaligned storage of length LEN.  */
3683 unsigned char *
3684 _cpp_unaligned_alloc (cpp_reader *pfile, size_t len)
3685 {
3686   _cpp_buff *buff = pfile->u_buff;
3687   unsigned char *result = buff->cur;
3688 
3689   if (len > (size_t) (buff->limit - result))
3690     {
3691       buff = _cpp_get_buff (pfile, len);
3692       buff->next = pfile->u_buff;
3693       pfile->u_buff = buff;
3694       result = buff->cur;
3695     }
3696 
3697   buff->cur = result + len;
3698   return result;
3699 }
3700 
3701 /* Allocate permanent, unaligned storage of length LEN from a_buff.
3702    That buffer is used for growing allocations when saving macro
3703    replacement lists in a #define, and when parsing an answer to an
3704    assertion in #assert, #unassert or #if (and therefore possibly
3705    whilst expanding macros).  It therefore must not be used by any
3706    code that they might call: specifically the lexer and the guts of
3707    the macro expander.
3708 
3709    All existing other uses clearly fit this restriction: storing
3710    registered pragmas during initialization.  */
3711 unsigned char *
3712 _cpp_aligned_alloc (cpp_reader *pfile, size_t len)
3713 {
3714   _cpp_buff *buff = pfile->a_buff;
3715   unsigned char *result = buff->cur;
3716 
3717   if (len > (size_t) (buff->limit - result))
3718     {
3719       buff = _cpp_get_buff (pfile, len);
3720       buff->next = pfile->a_buff;
3721       pfile->a_buff = buff;
3722       result = buff->cur;
3723     }
3724 
3725   buff->cur = result + len;
3726   return result;
3727 }
3728 
3729 /* Commit or allocate storage from a buffer.  */
3730 
3731 void *
3732 _cpp_commit_buff (cpp_reader *pfile, size_t size)
3733 {
3734   void *ptr = BUFF_FRONT (pfile->a_buff);
3735 
3736   if (pfile->hash_table->alloc_subobject)
3737     {
3738       void *copy = pfile->hash_table->alloc_subobject (size);
3739       memcpy (copy, ptr, size);
3740       ptr = copy;
3741     }
3742   else
3743     BUFF_FRONT (pfile->a_buff) += size;
3744 
3745   return ptr;
3746 }
3747 
3748 /* Say which field of TOK is in use.  */
3749 
3750 enum cpp_token_fld_kind
3751 cpp_token_val_index (const cpp_token *tok)
3752 {
3753   switch (TOKEN_SPELL (tok))
3754     {
3755     case SPELL_IDENT:
3756       return CPP_TOKEN_FLD_NODE;
3757     case SPELL_LITERAL:
3758       return CPP_TOKEN_FLD_STR;
3759     case SPELL_OPERATOR:
3760       if (tok->type == CPP_PASTE)
3761 	return CPP_TOKEN_FLD_TOKEN_NO;
3762       else
3763 	return CPP_TOKEN_FLD_NONE;
3764     case SPELL_NONE:
3765       if (tok->type == CPP_MACRO_ARG)
3766 	return CPP_TOKEN_FLD_ARG_NO;
3767       else if (tok->type == CPP_PADDING)
3768 	return CPP_TOKEN_FLD_SOURCE;
3769       else if (tok->type == CPP_PRAGMA)
3770 	return CPP_TOKEN_FLD_PRAGMA;
3771       /* fall through */
3772     default:
3773       return CPP_TOKEN_FLD_NONE;
3774     }
3775 }
3776 
3777 /* All tokens lexed in R after calling this function will be forced to
3778    have their location_t to be P, until
3779    cpp_stop_forcing_token_locations is called for R.  */
3780 
3781 void
3782 cpp_force_token_locations (cpp_reader *r, location_t loc)
3783 {
3784   r->forced_token_location = loc;
3785 }
3786 
3787 /* Go back to assigning locations naturally for lexed tokens.  */
3788 
3789 void
3790 cpp_stop_forcing_token_locations (cpp_reader *r)
3791 {
3792   r->forced_token_location = 0;
3793 }
3794