* java/lang/natRuntime.cc (insertSystemProperties): Set
[official-gcc.git] / gcc / gcov-io.h
blobd0bacff92802e6157ea57d0bac46ca4d59ec19d3
1 /* File format for coverage information
2 Copyright (C) 1996, 1997, 1998, 2000, 2002,
3 2003, 2004 Free Software Foundation, Inc.
4 Contributed by Bob Manson <manson@cygnus.com>.
5 Completely remangled by Nathan Sidwell <nathan@codesourcery.com>.
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
12 version.
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 02111-1307, USA. */
24 /* As a special exception, if you link this library with other files,
25 some of which are compiled with GCC, to produce an executable,
26 this library does not by itself cause the resulting executable
27 to be covered by the GNU General Public License.
28 This exception does not however invalidate any other reasons why
29 the executable file might be covered by the GNU General Public License. */
31 /* Coverage information is held in two files. A notes file, which is
32 generated by the compiler, and a data file, which is generated by
33 the program under test. Both files use a similar structure. We do
34 not attempt to make these files backwards compatible with previous
35 versions, as you only need coverage information when developing a
36 program. We do hold version information, so that mismatches can be
37 detected, and we use a format that allows tools to skip information
38 they do not understand or are not interested in.
40 Numbers are recorded in the 32 bit unsigned binary form of the
41 endianness of the machine generating the file. 64 bit numbers are
42 stored as two 32 bit numbers, the low part first. Strings are
43 padded with 1 to 4 NUL bytes, to bring the length up to a multiple
44 of 4. The number of 4 bytes is stored, followed by the padded
45 string. Zero length and NULL strings are simply stored as a length
46 of zero (they have no trailing NUL or padding).
48 int32: byte3 byte2 byte1 byte0 | byte0 byte1 byte2 byte3
49 int64: int32:low int32:high
50 string: int32:0 | int32:length char* char:0 padding
51 padding: | char:0 | char:0 char:0 | char:0 char:0 char:0
52 item: int32 | int64 | string
54 The basic format of the files is
56 file : int32:magic int32:version int32:stamp record*
58 The magic ident is different for the notes and the data files. The
59 magic ident is used to determine the endianness of the file, when
60 reading. The version is the same for both files and is derived
61 from gcc's version number. The stamp value is used to synchronize
62 note and data files and to synchronize merging within a data
63 file. It need not be an absolute time stamp, merely a ticker that
64 increments fast enough and cycles slow enough to distinguish
65 different compile/run/compile cycles.
67 Although the ident and version are formally 32 bit numbers, they
68 are derived from 4 character ASCII strings. The version number
69 consists of the single character major version number, a two
70 character minor version number (leading zero for versions less than
71 10), and a single character indicating the status of the release.
72 That will be 'e' experimental, 'p' prerelease and 'r' for release.
73 Because, by good fortune, these are in alphabetical order, string
74 collating can be used to compare version strings. Be aware that
75 the 'e' designation will (naturally) be unstable and might be
76 incompatible with itself. For gcc 3.4 experimental, it would be
77 '304e' (0x33303465). When the major version reaches 10, the
78 letters A-Z will be used. Assuming minor increments releases every
79 6 months, we have to make a major increment every 50 years.
80 Assuming major increments releases every 5 years, we're ok for the
81 next 155 years -- good enough for me.
83 A record has a tag, length and variable amount of data.
85 record: header data
86 header: int32:tag int32:length
87 data: item*
89 Records are not nested, but there is a record hierarchy. Tag
90 numbers reflect this hierarchy. Tags are unique across note and
91 data files. Some record types have a varying amount of data. The
92 LENGTH is the number of 4bytes that follow and is usually used to
93 determine how much data. The tag value is split into 4 8-bit
94 fields, one for each of four possible levels. The most significant
95 is allocated first. Unused levels are zero. Active levels are
96 odd-valued, so that the LSB of the level is one. A sub-level
97 incorporates the values of its superlevels. This formatting allows
98 you to determine the tag hierarchy, without understanding the tags
99 themselves, and is similar to the standard section numbering used
100 in technical documents. Level values [1..3f] are used for common
101 tags, values [41..9f] for the notes file and [a1..ff] for the data
102 file.
104 The basic block graph file contains the following records
105 note: unit function-graph*
106 unit: header int32:checksum string:source
107 function-graph: announce_function basic_blocks {arcs | lines}*
108 announce_function: header int32:ident int32:checksum
109 string:name string:source int32:lineno
110 basic_block: header int32:flags*
111 arcs: header int32:block_no arc*
112 arc: int32:dest_block int32:flags
113 lines: header int32:block_no line*
114 int32:0 string:NULL
115 line: int32:line_no | int32:0 string:filename
117 The BASIC_BLOCK record holds per-bb flags. The number of blocks
118 can be inferred from its data length. There is one ARCS record per
119 basic block. The number of arcs from a bb is implicit from the
120 data length. It enumerates the destination bb and per-arc flags.
121 There is one LINES record per basic block, it enumerates the source
122 lines which belong to that basic block. Source file names are
123 introduced by a line number of 0, following lines are from the new
124 source file. The initial source file for the function is NULL, but
125 the current source file should be remembered from one LINES record
126 to the next. The end of a block is indicated by an empty filename
127 - this does not reset the current source file. Note there is no
128 ordering of the ARCS and LINES records: they may be in any order,
129 interleaved in any manner. The current filename follows the order
130 the LINES records are stored in the file, *not* the ordering of the
131 blocks they are for.
133 The data file contains the following records.
134 data: {unit function-data* summary:object summary:program*}*
135 unit: header int32:checksum
136 function-data: announce_function arc_counts
137 announce_function: header int32:ident int32:checksum
138 arc_counts: header int64:count*
139 summary: int32:checksum {count-summary}GCOV_COUNTERS
140 count-summary: int32:num int32:runs int64:sum
141 int64:max int64:sum_max
143 The ANNOUNCE_FUNCTION record is the same as that in the note file,
144 but without the source location. The ARC_COUNTS gives the counter
145 values for those arcs that are instrumented. The SUMMARY records
146 give information about the whole object file and about the whole
147 program. The checksum is used for whole program summaries, and
148 disambiguates different programs which include the same
149 instrumented object file. There may be several program summaries,
150 each with a unique checksum. The object summary's checksum is zero.
151 Note that the data file might contain information from several runs
152 concatenated, or the data might be merged.
154 This file is included by both the compiler, gcov tools and the
155 runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to
156 distinguish which case is which. If IN_LIBGCOV is nonzero,
157 libgcov is being built. If IN_GCOV is nonzero, the gcov tools are
158 being built. Otherwise the compiler is being built. IN_GCOV may be
159 positive or negative. If positive, we are compiling a tool that
160 requires additional functions (see the code for knowledge of what
161 those functions are). */
163 #ifndef GCC_GCOV_IO_H
164 #define GCC_GCOV_IO_H
166 #if IN_LIBGCOV
167 /* About the target */
169 #if BITS_PER_UNIT == 8
170 typedef unsigned gcov_unsigned_t __attribute__ ((mode (SI)));
171 typedef unsigned gcov_position_t __attribute__ ((mode (SI)));
172 #if LONG_LONG_TYPE_SIZE > 32
173 typedef signed gcov_type __attribute__ ((mode (DI)));
174 #else
175 typedef signed gcov_type __attribute__ ((mode (SI)));
176 #endif
177 #else
178 #if BITS_PER_UNIT == 16
179 typedef unsigned gcov_unsigned_t __attribute__ ((mode (HI)));
180 typedef unsigned gcov_position_t __attribute__ ((mode (HI)));
181 #if LONG_LONG_TYPE_SIZE > 32
182 typedef signed gcov_type __attribute__ ((mode (SI)));
183 #else
184 typedef signed gcov_type __attribute__ ((mode (HI)));
185 #endif
186 #else
187 typedef unsigned gcov_unsigned_t __attribute__ ((mode (QI)));
188 typedef unsigned gcov_position_t __attribute__ ((mode (QI)));
189 #if LONG_LONG_TYPE_SIZE > 32
190 typedef signed gcov_type __attribute__ ((mode (HI)));
191 #else
192 typedef signed gcov_type __attribute__ ((mode (QI)));
193 #endif
194 #endif
195 #endif
198 #if defined (TARGET_HAS_F_SETLKW)
199 #define GCOV_LOCKED 1
200 #else
201 #define GCOV_LOCKED 0
202 #endif
204 #else /* !IN_LIBGCOV */
205 /* About the host */
207 typedef unsigned gcov_unsigned_t;
208 typedef unsigned gcov_position_t;
209 /* gcov_type is typedef'd elsewhere for the compiler */
210 #if IN_GCOV
211 #define GCOV_LINKAGE static
212 typedef HOST_WIDEST_INT gcov_type;
213 #if IN_GCOV > 0
214 #include <sys/types.h>
215 #endif
216 #else /*!IN_GCOV */
217 #define GCOV_TYPE_SIZE (LONG_LONG_TYPE_SIZE > 32 ? 64 : 32)
218 #endif
220 #if defined (HOST_HAS_F_SETLKW)
221 #define GCOV_LOCKED 1
222 #else
223 #define GCOV_LOCKED 0
224 #endif
226 #endif /* !IN_LIBGCOV */
228 /* In gcov we want function linkage to be static. In libgcov we need
229 these functions to be extern, so prefix them with __gcov. In the
230 compiler we want it extern, so that they can be accessed from
231 elsewhere. */
232 #if IN_LIBGCOV
233 #define gcov_var __gcov_var
234 #define gcov_open __gcov_open
235 #define gcov_close __gcov_close
236 #define gcov_write_tag_length __gcov_write_tag_length
237 #define gcov_position __gcov_position
238 #define gcov_seek __gcov_seek
239 #define gcov_rewrite __gcov_rewrite
240 #define gcov_is_error __gcov_is_error
241 #define gcov_write_unsigned __gcov_write_unsigned
242 #define gcov_write_counter __gcov_write_counter
243 #define gcov_write_summary __gcov_write_summary
244 #define gcov_read_unsigned __gcov_read_unsigned
245 #define gcov_read_counter __gcov_read_counter
246 #define gcov_read_summary __gcov_read_summary
248 /* Poison these, so they don't accidentally slip in. */
249 #pragma GCC poison gcov_write_string gcov_write_tag gcov_write_length
250 #pragma GCC poison gcov_read_string gcov_sync gcov_time gcov_magic
252 #endif
254 #ifndef GCOV_LINKAGE
255 #define GCOV_LINKAGE extern
256 #endif
258 /* File suffixes. */
259 #define GCOV_DATA_SUFFIX ".gcda"
260 #define GCOV_NOTE_SUFFIX ".gcno"
262 /* File magic. Must not be palindromes. */
263 #define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */
264 #define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */
266 /* gcov-iov.h is automatically generated by the makefile from
267 version.c, it looks like
268 #define GCOV_VERSION ((gcov_unsigned_t)0x89abcdef)
270 #include "gcov-iov.h"
272 /* Convert a magic or version number to a 4 character string. */
273 #define GCOV_UNSIGNED2STRING(ARRAY,VALUE) \
274 ((ARRAY)[0] = (char)((VALUE) >> 24), \
275 (ARRAY)[1] = (char)((VALUE) >> 16), \
276 (ARRAY)[2] = (char)((VALUE) >> 8), \
277 (ARRAY)[3] = (char)((VALUE) >> 0))
279 /* The record tags. Values [1..3f] are for tags which may be in either
280 file. Values [41..9f] for those in the note file and [a1..ff] for
281 the data file. The tag value zero is used as an explicit end of
282 file marker -- it is not required to be present. */
284 #define GCOV_TAG_FUNCTION ((gcov_unsigned_t)0x01000000)
285 #define GCOV_TAG_FUNCTION_LENGTH (2)
286 #define GCOV_TAG_BLOCKS ((gcov_unsigned_t)0x01410000)
287 #define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM)
288 #define GCOV_TAG_BLOCKS_NUM(LENGTH) (LENGTH)
289 #define GCOV_TAG_ARCS ((gcov_unsigned_t)0x01430000)
290 #define GCOV_TAG_ARCS_LENGTH(NUM) (1 + (NUM) * 2)
291 #define GCOV_TAG_ARCS_NUM(LENGTH) (((LENGTH) - 1) / 2)
292 #define GCOV_TAG_LINES ((gcov_unsigned_t)0x01450000)
293 #define GCOV_TAG_COUNTER_BASE ((gcov_unsigned_t)0x01a10000)
294 #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2)
295 #define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2)
296 #define GCOV_TAG_OBJECT_SUMMARY ((gcov_unsigned_t)0xa1000000)
297 #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000)
298 #define GCOV_TAG_SUMMARY_LENGTH \
299 (1 + GCOV_COUNTERS_SUMMABLE * (2 + 3 * 2))
301 /* Counters that are collected. */
302 #define GCOV_COUNTER_ARCS 0 /* Arc transitions. */
303 #define GCOV_COUNTERS_SUMMABLE 1 /* Counters which can be
304 summaried. */
305 #define GCOV_FIRST_VALUE_COUNTER 1 /* The first of counters used for value
306 profiling. They must form a consecutive
307 interval and their order must match
308 the order of HIST_TYPEs in
309 value-prof.h. */
310 #define GCOV_COUNTER_V_INTERVAL 1 /* Histogram of value inside an interval. */
311 #define GCOV_COUNTER_V_POW2 2 /* Histogram of exact power2 logarithm
312 of a value. */
313 #define GCOV_COUNTER_V_SINGLE 3 /* The most common value of expression. */
314 #define GCOV_COUNTER_V_DELTA 4 /* The most common difference between
315 consecutive values of expression. */
316 #define GCOV_LAST_VALUE_COUNTER 4 /* The last of counters used for value
317 profiling. */
318 #define GCOV_COUNTERS 5
320 /* Number of counters used for value profiling. */
321 #define GCOV_N_VALUE_COUNTERS \
322 (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1)
324 /* A list of human readable names of the counters */
325 #define GCOV_COUNTER_NAMES {"arcs", "interval", "pow2", "single", "delta"}
327 /* Names of merge functions for counters. */
328 #define GCOV_MERGE_FUNCTIONS {"__gcov_merge_add", \
329 "__gcov_merge_add", \
330 "__gcov_merge_add", \
331 "__gcov_merge_single", \
332 "__gcov_merge_delta"}
334 /* Convert a counter index to a tag. */
335 #define GCOV_TAG_FOR_COUNTER(COUNT) \
336 (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17))
337 /* Convert a tag to a counter. */
338 #define GCOV_COUNTER_FOR_TAG(TAG) \
339 ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17))
340 /* Check whether a tag is a counter tag. */
341 #define GCOV_TAG_IS_COUNTER(TAG) \
342 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS)
344 /* The tag level mask has 1's in the position of the inner levels, &
345 the lsb of the current level, and zero on the current and outer
346 levels. */
347 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
349 /* Return nonzero if SUB is an immediate subtag of TAG. */
350 #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \
351 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \
352 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK(TAG)))
354 /* Return nonzero if SUB is at a sublevel to TAG. */
355 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \
356 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
358 /* Basic block flags. */
359 #define GCOV_BLOCK_UNEXPECTED (1 << 1)
361 /* Arc flags. */
362 #define GCOV_ARC_ON_TREE (1 << 0)
363 #define GCOV_ARC_FAKE (1 << 1)
364 #define GCOV_ARC_FALLTHROUGH (1 << 2)
366 /* Structured records. */
368 /* Cumulative counter data. */
369 struct gcov_ctr_summary
371 gcov_unsigned_t num; /* number of counters. */
372 gcov_unsigned_t runs; /* number of program runs */
373 gcov_type sum_all; /* sum of all counters accumulated. */
374 gcov_type run_max; /* maximum value on a single run. */
375 gcov_type sum_max; /* sum of individual run max values. */
378 /* Object & program summary record. */
379 struct gcov_summary
381 gcov_unsigned_t checksum; /* checksum of program */
382 struct gcov_ctr_summary ctrs[GCOV_COUNTERS_SUMMABLE];
385 /* Structures embedded in coveraged program. The structures generated
386 by write_profile must match these. */
388 #if IN_LIBGCOV
389 /* Information about a single function. This uses the trailing array
390 idiom. The number of counters is determined from the counter_mask
391 in gcov_info. We hold an array of function info, so have to
392 explicitly calculate the correct array stride. */
393 struct gcov_fn_info
395 gcov_unsigned_t ident; /* unique ident of function */
396 gcov_unsigned_t checksum; /* function checksum */
397 unsigned n_ctrs[0]; /* instrumented counters */
400 /* Type of function used to merge counters. */
401 typedef void (*gcov_merge_fn) (gcov_type *, gcov_unsigned_t);
403 /* Information about counters. */
404 struct gcov_ctr_info
406 gcov_unsigned_t num; /* number of counters. */
407 gcov_type *values; /* their values. */
408 gcov_merge_fn merge; /* The function used to merge them. */
411 /* Information about a single object file. */
412 struct gcov_info
414 gcov_unsigned_t version; /* expected version number */
415 struct gcov_info *next; /* link to next, used by libgcov */
417 gcov_unsigned_t stamp; /* uniquifying time stamp */
418 const char *filename; /* output file name */
420 unsigned n_functions; /* number of functions */
421 const struct gcov_fn_info *functions; /* table of functions */
423 unsigned ctr_mask; /* mask of counters instrumented. */
424 struct gcov_ctr_info counts[0]; /* count data. The number of bits
425 set in the ctr_mask field
426 determines how big this array
427 is. */
430 /* Register a new object file module. */
431 extern void __gcov_init (struct gcov_info *);
433 /* Called before fork, to avoid double counting. */
434 extern void __gcov_flush (void);
436 /* The merge function that just sums the counters. */
437 extern void __gcov_merge_add (gcov_type *, unsigned);
439 /* The merge function to choose the most common value. */
440 extern void __gcov_merge_single (gcov_type *, unsigned);
442 /* The merge function to choose the most common difference between
443 consecutive values. */
444 extern void __gcov_merge_delta (gcov_type *, unsigned);
446 #ifndef inhibit_libc
447 /* The wrappers around some library functions.. */
448 extern pid_t __gcov_fork (void);
449 extern int __gcov_execl (const char *, const char *, ...);
450 extern int __gcov_execlp (const char *, const char *, ...);
451 extern int __gcov_execle (const char *, const char *, ...);
452 extern int __gcov_execv (const char *, char *const []);
453 extern int __gcov_execvp (const char *, char *const []);
454 extern int __gcov_execve (const char *, char *const [], char *const []);
455 #endif
457 #endif /* IN_LIBGCOV */
459 #if IN_LIBGCOV >= 0
461 /* Optimum number of gcov_unsigned_t's read from or written to disk. */
462 #define GCOV_BLOCK_SIZE (1 << 10)
464 GCOV_LINKAGE struct gcov_var
466 FILE *file;
467 gcov_position_t start; /* Position of first byte of block */
468 unsigned offset; /* Read/write position within the block. */
469 unsigned length; /* Read limit in the block. */
470 unsigned overread; /* Number of words overread. */
471 int error; /* < 0 overflow, > 0 disk error. */
472 int mode; /* < 0 writing, > 0 reading */
473 #if IN_LIBGCOV
474 /* Holds one block plus 4 bytes, thus all coverage reads & writes
475 fit within this buffer and we always can transfer GCOV_BLOCK_SIZE
476 to and from the disk. libgcov never backtracks and only writes 4
477 or 8 byte objects. */
478 gcov_unsigned_t buffer[GCOV_BLOCK_SIZE + 1];
479 #else
480 int endian; /* Swap endianness. */
481 /* Holds a variable length block, as the compiler can write
482 strings and needs to backtrack. */
483 size_t alloc;
484 gcov_unsigned_t *buffer;
485 #endif
486 } gcov_var;
488 /* Functions for reading and writing gcov files. In libgcov you can
489 open the file for reading then writing. Elsewhere you can open the
490 file either for reading or for writing. When reading a file you may
491 use the gcov_read_* functions, gcov_sync, gcov_position, &
492 gcov_error. When writing a file you may use the gcov_write
493 functions, gcov_seek & gcov_error. When a file is to be rewritten
494 you use the functions for reading, then gcov_rewrite then the
495 functions for writing. Your file may become corrupted if you break
496 these invariants. */
497 #if IN_LIBGCOV
498 GCOV_LINKAGE int gcov_open (const char */*name*/);
499 #else
500 GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/);
501 GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t);
502 #endif
503 GCOV_LINKAGE int gcov_close (void);
505 /* Available everywhere. */
506 static gcov_position_t gcov_position (void);
507 static int gcov_is_error (void);
509 GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void);
510 GCOV_LINKAGE gcov_type gcov_read_counter (void);
511 GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *);
513 #if IN_LIBGCOV
514 /* Available only in libgcov */
515 GCOV_LINKAGE void gcov_write_counter (gcov_type);
516 GCOV_LINKAGE void gcov_write_tag_length (gcov_unsigned_t, gcov_unsigned_t);
517 GCOV_LINKAGE void gcov_write_summary (gcov_unsigned_t /*tag*/,
518 const struct gcov_summary *);
519 static void gcov_rewrite (void);
520 GCOV_LINKAGE void gcov_seek (gcov_position_t /*position*/);
521 #else
522 /* Available outside libgcov */
523 GCOV_LINKAGE const char *gcov_read_string (void);
524 GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/,
525 gcov_unsigned_t /*length */);
526 #endif
528 #if !IN_GCOV
529 /* Available outside gcov */
530 GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t);
531 #endif
533 #if !IN_GCOV && !IN_LIBGCOV
534 /* Available only in compiler */
535 GCOV_LINKAGE void gcov_write_string (const char *);
536 GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t);
537 GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/);
538 #endif
540 #if IN_GCOV > 0
541 /* Available in gcov */
542 GCOV_LINKAGE time_t gcov_time (void);
543 #endif
545 /* Save the current position in the gcov file. */
547 static inline gcov_position_t
548 gcov_position (void)
550 gcc_assert (gcov_var.mode > 0);
551 return gcov_var.start + gcov_var.offset;
554 /* Return nonzero if the error flag is set. */
556 static inline int
557 gcov_is_error (void)
559 return gcov_var.file ? gcov_var.error : 1;
562 #if IN_LIBGCOV
563 /* Move to beginning of file and initialize for writing. */
565 static inline void
566 gcov_rewrite (void)
568 gcc_assert (gcov_var.mode > 0);
569 gcov_var.mode = -1;
570 gcov_var.start = 0;
571 gcov_var.offset = 0;
572 fseek (gcov_var.file, 0L, SEEK_SET);
574 #endif
576 #endif /* IN_LIBGCOV >= 0 */
578 #endif /* GCC_GCOV_IO_H */