1/* File format for coverage information
2   Copyright (C) 1996-2015 Free Software Foundation, Inc.
3   Contributed by Bob Manson <manson@cygnus.com>.
4   Completely remangled by Nathan Sidwell <nathan@codesourcery.com>.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16for more details.
17
18Under Section 7 of GPL version 3, you are granted additional
19permissions described in the GCC Runtime Library Exception, version
203.1, as published by the Free Software Foundation.
21
22You should have received a copy of the GNU General Public License and
23a copy of the GCC Runtime Library Exception along with this program;
24see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
25<http://www.gnu.org/licenses/>.  */
26
27
28/* Coverage information is held in two files.  A notes file, which is
29   generated by the compiler, and a data file, which is generated by
30   the program under test.  Both files use a similar structure.  We do
31   not attempt to make these files backwards compatible with previous
32   versions, as you only need coverage information when developing a
33   program.  We do hold version information, so that mismatches can be
34   detected, and we use a format that allows tools to skip information
35   they do not understand or are not interested in.
36
37   Numbers are recorded in the 32 bit unsigned binary form of the
38   endianness of the machine generating the file. 64 bit numbers are
39   stored as two 32 bit numbers, the low part first.  Strings are
40   padded with 1 to 4 NUL bytes, to bring the length up to a multiple
41   of 4. The number of 4 bytes is stored, followed by the padded
42   string. Zero length and NULL strings are simply stored as a length
43   of zero (they have no trailing NUL or padding).
44
45   	int32:  byte3 byte2 byte1 byte0 | byte0 byte1 byte2 byte3
46	int64:  int32:low int32:high
47	string: int32:0 | int32:length char* char:0 padding
48	padding: | char:0 | char:0 char:0 | char:0 char:0 char:0
49	item: int32 | int64 | string
50
51   The basic format of the files is
52
53   	file : int32:magic int32:version int32:stamp record*
54
55   The magic ident is different for the notes and the data files.  The
56   magic ident is used to determine the endianness of the file, when
57   reading.  The version is the same for both files and is derived
58   from gcc's version number. The stamp value is used to synchronize
59   note and data files and to synchronize merging within a data
60   file. It need not be an absolute time stamp, merely a ticker that
61   increments fast enough and cycles slow enough to distinguish
62   different compile/run/compile cycles.
63
64   Although the ident and version are formally 32 bit numbers, they
65   are derived from 4 character ASCII strings.  The version number
66   consists of the single character major version number, a two
67   character minor version number (leading zero for versions less than
68   10), and a single character indicating the status of the release.
69   That will be 'e' experimental, 'p' prerelease and 'r' for release.
70   Because, by good fortune, these are in alphabetical order, string
71   collating can be used to compare version strings.  Be aware that
72   the 'e' designation will (naturally) be unstable and might be
73   incompatible with itself.  For gcc 3.4 experimental, it would be
74   '304e' (0x33303465).  When the major version reaches 10, the
75   letters A-Z will be used.  Assuming minor increments releases every
76   6 months, we have to make a major increment every 50 years.
77   Assuming major increments releases every 5 years, we're ok for the
78   next 155 years -- good enough for me.
79
80   A record has a tag, length and variable amount of data.
81
82   	record: header data
83	header: int32:tag int32:length
84	data: item*
85
86   Records are not nested, but there is a record hierarchy.  Tag
87   numbers reflect this hierarchy.  Tags are unique across note and
88   data files.  Some record types have a varying amount of data.  The
89   LENGTH is the number of 4bytes that follow and is usually used to
90   determine how much data.  The tag value is split into 4 8-bit
91   fields, one for each of four possible levels.  The most significant
92   is allocated first.  Unused levels are zero.  Active levels are
93   odd-valued, so that the LSB of the level is one.  A sub-level
94   incorporates the values of its superlevels.  This formatting allows
95   you to determine the tag hierarchy, without understanding the tags
96   themselves, and is similar to the standard section numbering used
97   in technical documents.  Level values [1..3f] are used for common
98   tags, values [41..9f] for the notes file and [a1..ff] for the data
99   file.
100
101   The notes file contains the following records
102   	note: unit function-graph*
103	unit: header int32:checksum string:source
104	function-graph: announce_function basic_blocks {arcs | lines}*
105	announce_function: header int32:ident
106		int32:lineno_checksum int32:cfg_checksum
107		string:name string:source int32:lineno
108	basic_block: header int32:flags*
109	arcs: header int32:block_no arc*
110	arc:  int32:dest_block int32:flags
111        lines: header int32:block_no line*
112               int32:0 string:NULL
113	line:  int32:line_no | int32:0 string:filename
114
115   The BASIC_BLOCK record holds per-bb flags.  The number of blocks
116   can be inferred from its data length.  There is one ARCS record per
117   basic block.  The number of arcs from a bb is implicit from the
118   data length.  It enumerates the destination bb and per-arc flags.
119   There is one LINES record per basic block, it enumerates the source
120   lines which belong to that basic block.  Source file names are
121   introduced by a line number of 0, following lines are from the new
122   source file.  The initial source file for the function is NULL, but
123   the current source file should be remembered from one LINES record
124   to the next.  The end of a block is indicated by an empty filename
125   - this does not reset the current source file.  Note there is no
126   ordering of the ARCS and LINES records: they may be in any order,
127   interleaved in any manner.  The current filename follows the order
128   the LINES records are stored in the file, *not* the ordering of the
129   blocks they are for.
130
131   The data file contains the following records.
132        data: {unit summary:object summary:program* function-data*}*
133	unit: header int32:checksum
134        function-data:	announce_function present counts
135	announce_function: header int32:ident
136		int32:lineno_checksum int32:cfg_checksum
137	present: header int32:present
138	counts: header int64:count*
139	summary: int32:checksum {count-summary}GCOV_COUNTERS_SUMMABLE
140	count-summary:	int32:num int32:runs int64:sum
141			int64:max int64:sum_max histogram
142        histogram: {int32:bitvector}8 histogram-buckets*
143        histogram-buckets: int32:num int64:min int64:sum
144
145   The ANNOUNCE_FUNCTION record is the same as that in the note file,
146   but without the source location.  The COUNTS gives the
147   counter values for instrumented features.  The about the whole
148   program.  The checksum is used for whole program summaries, and
149   disambiguates different programs which include the same
150   instrumented object file.  There may be several program summaries,
151   each with a unique checksum.  The object summary's checksum is
152   zero.  Note that the data file might contain information from
153   several runs concatenated, or the data might be merged.
154
155   This file is included by both the compiler, gcov tools and the
156   runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to
157   distinguish which case is which.  If IN_LIBGCOV is nonzero,
158   libgcov is being built. If IN_GCOV is nonzero, the gcov tools are
159   being built. Otherwise the compiler is being built. IN_GCOV may be
160   positive or negative. If positive, we are compiling a tool that
161   requires additional functions (see the code for knowledge of what
162   those functions are).  */
163
164#ifndef GCC_GCOV_IO_H
165#define GCC_GCOV_IO_H
166
167#ifndef IN_LIBGCOV
168/* About the host */
169
170typedef unsigned gcov_unsigned_t;
171typedef unsigned gcov_position_t;
172/* gcov_type is typedef'd elsewhere for the compiler */
173#if IN_GCOV
174#define GCOV_LINKAGE static
175typedef int64_t gcov_type;
176typedef uint64_t gcov_type_unsigned;
177#if IN_GCOV > 0
178#include <sys/types.h>
179#endif
180#else /*!IN_GCOV */
181#define GCOV_TYPE_SIZE (LONG_LONG_TYPE_SIZE > 32 ? 64 : 32)
182#endif
183
184#if defined (HOST_HAS_F_SETLKW)
185#define GCOV_LOCKED 1
186#else
187#define GCOV_LOCKED 0
188#endif
189
190#define ATTRIBUTE_HIDDEN
191
192#endif /* !IN_LIBGOCV */
193
194#ifndef GCOV_LINKAGE
195#define GCOV_LINKAGE extern
196#endif
197
198#if IN_LIBGCOV
199#define gcov_nonruntime_assert(EXPR) ((void)(0 && (EXPR)))
200#else
201#define gcov_nonruntime_assert(EXPR) gcc_assert (EXPR)
202#define gcov_error(...) fatal_error (input_location, __VA_ARGS__)
203#endif
204
205/* File suffixes.  */
206#define GCOV_DATA_SUFFIX ".gcda"
207#define GCOV_NOTE_SUFFIX ".gcno"
208
209/* File magic. Must not be palindromes.  */
210#define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */
211#define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */
212
213/* gcov-iov.h is automatically generated by the makefile from
214   version.c, it looks like
215   	#define GCOV_VERSION ((gcov_unsigned_t)0x89abcdef)
216*/
217#include "gcov-iov.h"
218
219/* Convert a magic or version number to a 4 character string.  */
220#define GCOV_UNSIGNED2STRING(ARRAY,VALUE)	\
221  ((ARRAY)[0] = (char)((VALUE) >> 24),		\
222   (ARRAY)[1] = (char)((VALUE) >> 16),		\
223   (ARRAY)[2] = (char)((VALUE) >> 8),		\
224   (ARRAY)[3] = (char)((VALUE) >> 0))
225
226/* The record tags.  Values [1..3f] are for tags which may be in either
227   file.  Values [41..9f] for those in the note file and [a1..ff] for
228   the data file.  The tag value zero is used as an explicit end of
229   file marker -- it is not required to be present.  */
230
231#define GCOV_TAG_FUNCTION	 ((gcov_unsigned_t)0x01000000)
232#define GCOV_TAG_FUNCTION_LENGTH (3)
233#define GCOV_TAG_BLOCKS		 ((gcov_unsigned_t)0x01410000)
234#define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM)
235#define GCOV_TAG_BLOCKS_NUM(LENGTH) (LENGTH)
236#define GCOV_TAG_ARCS		 ((gcov_unsigned_t)0x01430000)
237#define GCOV_TAG_ARCS_LENGTH(NUM)  (1 + (NUM) * 2)
238#define GCOV_TAG_ARCS_NUM(LENGTH)  (((LENGTH) - 1) / 2)
239#define GCOV_TAG_LINES		 ((gcov_unsigned_t)0x01450000)
240#define GCOV_TAG_COUNTER_BASE 	 ((gcov_unsigned_t)0x01a10000)
241#define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2)
242#define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2)
243#define GCOV_TAG_OBJECT_SUMMARY  ((gcov_unsigned_t)0xa1000000) /* Obsolete */
244#define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000)
245#define GCOV_TAG_SUMMARY_LENGTH(NUM)  \
246        (1 + GCOV_COUNTERS_SUMMABLE * (10 + 3 * 2) + (NUM) * 5)
247#define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000)
248#define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000)
249#define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000)
250
251
252/* Counters that are collected.  */
253
254#define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER,
255enum {
256#include "gcov-counter.def"
257GCOV_COUNTERS
258};
259#undef DEF_GCOV_COUNTER
260
261/* Counters which can be summaried.  */
262#define GCOV_COUNTERS_SUMMABLE	(GCOV_COUNTER_ARCS + 1)
263
264/* The first of counters used for value profiling.  They must form a
265   consecutive interval and their order must match the order of
266   HIST_TYPEs in value-prof.h.  */
267#define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTERS_SUMMABLE
268
269/* The last of counters used for value profiling.  */
270#define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1)
271
272/* Number of counters used for value profiling.  */
273#define GCOV_N_VALUE_COUNTERS \
274  (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1)
275
276/* The number of hottest callees to be tracked.  */
277#define GCOV_ICALL_TOPN_VAL  2
278
279/* The number of counter entries per icall callsite.  */
280#define GCOV_ICALL_TOPN_NCOUNTS (1 + GCOV_ICALL_TOPN_VAL * 4)
281
282/* Convert a counter index to a tag.  */
283#define GCOV_TAG_FOR_COUNTER(COUNT)				\
284	(GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17))
285/* Convert a tag to a counter.  */
286#define GCOV_COUNTER_FOR_TAG(TAG)					\
287	((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17))
288/* Check whether a tag is a counter tag.  */
289#define GCOV_TAG_IS_COUNTER(TAG)				\
290	(!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS)
291
292/* The tag level mask has 1's in the position of the inner levels, &
293   the lsb of the current level, and zero on the current and outer
294   levels.  */
295#define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
296
297/* Return nonzero if SUB is an immediate subtag of TAG.  */
298#define GCOV_TAG_IS_SUBTAG(TAG,SUB)				\
299	(GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) 	\
300	 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG)))
301
302/* Return nonzero if SUB is at a sublevel to TAG.  */
303#define GCOV_TAG_IS_SUBLEVEL(TAG,SUB)				\
304     	(GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
305
306/* Basic block flags.  */
307#define GCOV_BLOCK_UNEXPECTED	(1 << 1)
308
309/* Arc flags.  */
310#define GCOV_ARC_ON_TREE 	(1 << 0)
311#define GCOV_ARC_FAKE		(1 << 1)
312#define GCOV_ARC_FALLTHROUGH	(1 << 2)
313
314/* Structured records.  */
315
316/* Structure used for each bucket of the log2 histogram of counter values.  */
317typedef struct
318{
319  /* Number of counters whose profile count falls within the bucket.  */
320  gcov_unsigned_t num_counters;
321  /* Smallest profile count included in this bucket.  */
322  gcov_type min_value;
323  /* Cumulative value of the profile counts in this bucket.  */
324  gcov_type cum_value;
325} gcov_bucket_type;
326
327/* For a log2 scale histogram with each range split into 4
328   linear sub-ranges, there will be at most 64 (max gcov_type bit size) - 1 log2
329   ranges since the lowest 2 log2 values share the lowest 4 linear
330   sub-range (values 0 - 3).  This is 252 total entries (63*4).  */
331
332#define GCOV_HISTOGRAM_SIZE 252
333
334/* How many unsigned ints are required to hold a bit vector of non-zero
335   histogram entries when the histogram is written to the gcov file.
336   This is essentially a ceiling divide by 32 bits.  */
337#define GCOV_HISTOGRAM_BITVECTOR_SIZE (GCOV_HISTOGRAM_SIZE + 31) / 32
338
339/* Cumulative counter data.  */
340struct gcov_ctr_summary
341{
342  gcov_unsigned_t num;		/* number of counters.  */
343  gcov_unsigned_t runs;		/* number of program runs */
344  gcov_type sum_all;		/* sum of all counters accumulated.  */
345  gcov_type run_max;		/* maximum value on a single run.  */
346  gcov_type sum_max;    	/* sum of individual run max values.  */
347  gcov_bucket_type histogram[GCOV_HISTOGRAM_SIZE]; /* histogram of
348                                                      counter values.  */
349};
350
351/* Object & program summary record.  */
352struct gcov_summary
353{
354  gcov_unsigned_t checksum;	/* checksum of program */
355  struct gcov_ctr_summary ctrs[GCOV_COUNTERS_SUMMABLE];
356};
357
358#if !defined(inhibit_libc)
359
360/* Functions for reading and writing gcov files. In libgcov you can
361   open the file for reading then writing. Elsewhere you can open the
362   file either for reading or for writing. When reading a file you may
363   use the gcov_read_* functions, gcov_sync, gcov_position, &
364   gcov_error. When writing a file you may use the gcov_write
365   functions, gcov_seek & gcov_error. When a file is to be rewritten
366   you use the functions for reading, then gcov_rewrite then the
367   functions for writing.  Your file may become corrupted if you break
368   these invariants.  */
369
370#if !IN_LIBGCOV
371GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/);
372GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t);
373#endif
374
375/* Available everywhere.  */
376GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN;
377GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN;
378GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN;
379GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN;
380GCOV_LINKAGE const char *gcov_read_string (void);
381GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/,
382			     gcov_unsigned_t /*length */);
383
384#if !IN_GCOV
385/* Available outside gcov */
386GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN;
387#endif
388
389#if !IN_GCOV && !IN_LIBGCOV
390/* Available only in compiler */
391GCOV_LINKAGE unsigned gcov_histo_index (gcov_type value);
392GCOV_LINKAGE void gcov_write_string (const char *);
393GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t);
394GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/);
395#endif
396
397#if IN_GCOV <= 0 && !IN_LIBGCOV
398/* Available in gcov-dump and the compiler.  */
399
400/* Number of data points in the working set summary array. Using 128
401   provides information for at least every 1% increment of the total
402   profile size. The last entry is hardwired to 99.9% of the total.  */
403#define NUM_GCOV_WORKING_SETS 128
404
405/* Working set size statistics for a given percentage of the entire
406   profile (sum_all from the counter summary).  */
407typedef struct gcov_working_set_info
408{
409  /* Number of hot counters included in this working set.  */
410  unsigned num_counters;
411  /* Smallest counter included in this working set.  */
412  gcov_type min_counter;
413} gcov_working_set_t;
414
415GCOV_LINKAGE void compute_working_sets (const struct gcov_ctr_summary *summary,
416                                        gcov_working_set_t *gcov_working_sets);
417#endif
418
419#if IN_GCOV > 0
420/* Available in gcov */
421GCOV_LINKAGE time_t gcov_time (void);
422#endif
423
424#endif /* !inhibit_libc  */
425
426#endif /* GCC_GCOV_IO_H */
427