1/* File format for coverage information
2   Copyright (C) 1996-2020 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 notes file is
52
53	file : int32:magic int32:version int32:stamp int32:support_unexecuted_blocks record*
54
55   The basic format of the data file is
56
57   	file : int32:magic int32:version int32:stamp record*
58
59   The magic ident is different for the notes and the data files.  The
60   magic ident is used to determine the endianness of the file, when
61   reading.  The version is the same for both files and is derived
62   from gcc's version number. The stamp value is used to synchronize
63   note and data files and to synchronize merging within a data
64   file. It need not be an absolute time stamp, merely a ticker that
65   increments fast enough and cycles slow enough to distinguish
66   different compile/run/compile cycles.
67
68   Although the ident and version are formally 32 bit numbers, they
69   are derived from 4 character ASCII strings.  The version number
70   consists of a two character major version number
71   (first digit starts from 'A' letter to not to clash with the older
72   numbering scheme), the single character minor version number,
73   and a single character indicating the status of the release.
74   That will be 'e' experimental, 'p' prerelease and 'r' for release.
75   Because, by good fortune, these are in alphabetical order, string
76   collating can be used to compare version strings.  Be aware that
77   the 'e' designation will (naturally) be unstable and might be
78   incompatible with itself.  For gcc 17.0 experimental, it would be
79   'B70e' (0x42373065).  As we currently do not release more than 5 minor
80   releases, the single character should be always fine.  Major number
81   is currently changed roughly every year, which gives us space
82   for next 250 years (maximum allowed number would be 259.9).
83
84   A record has a tag, length and variable amount of data.
85
86   	record: header data
87	header: int32:tag int32:length
88	data: item*
89
90   Records are not nested, but there is a record hierarchy.  Tag
91   numbers reflect this hierarchy.  Tags are unique across note and
92   data files.  Some record types have a varying amount of data.  The
93   LENGTH is the number of 4bytes that follow and is usually used to
94   determine how much data.  The tag value is split into 4 8-bit
95   fields, one for each of four possible levels.  The most significant
96   is allocated first.  Unused levels are zero.  Active levels are
97   odd-valued, so that the LSB of the level is one.  A sub-level
98   incorporates the values of its superlevels.  This formatting allows
99   you to determine the tag hierarchy, without understanding the tags
100   themselves, and is similar to the standard section numbering used
101   in technical documents.  Level values [1..3f] are used for common
102   tags, values [41..9f] for the notes file and [a1..ff] for the data
103   file.
104
105   The notes file contains the following records
106   	note: unit function-graph*
107	unit: header int32:checksum string:source
108	function-graph: announce_function basic_blocks {arcs | lines}*
109	announce_function: header int32:ident
110		int32:lineno_checksum int32:cfg_checksum
111		string:name string:source int32:start_lineno int32:start_column int32:end_lineno
112	basic_block: header int32:flags*
113	arcs: header int32:block_no arc*
114	arc:  int32:dest_block int32:flags
115        lines: header int32:block_no line*
116               int32:0 string:NULL
117	line:  int32:line_no | int32:0 string:filename
118
119   The BASIC_BLOCK record holds per-bb flags.  The number of blocks
120   can be inferred from its data length.  There is one ARCS record per
121   basic block.  The number of arcs from a bb is implicit from the
122   data length.  It enumerates the destination bb and per-arc flags.
123   There is one LINES record per basic block, it enumerates the source
124   lines which belong to that basic block.  Source file names are
125   introduced by a line number of 0, following lines are from the new
126   source file.  The initial source file for the function is NULL, but
127   the current source file should be remembered from one LINES record
128   to the next.  The end of a block is indicated by an empty filename
129   - this does not reset the current source file.  Note there is no
130   ordering of the ARCS and LINES records: they may be in any order,
131   interleaved in any manner.  The current filename follows the order
132   the LINES records are stored in the file, *not* the ordering of the
133   blocks they are for.
134
135   The data file contains the following records.
136	data: {unit summary:object function-data*}*
137	unit: header int32:checksum
138	function-data:	announce_function present counts
139	announce_function: header int32:ident
140		int32:lineno_checksum int32:cfg_checksum
141	present: header int32:present
142	counts: header int64:count*
143	summary: int32:checksum int32:runs int32:sum_max
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#endif
181
182#if defined (HOST_HAS_F_SETLKW)
183#define GCOV_LOCKED 1
184#else
185#define GCOV_LOCKED 0
186#endif
187
188#define ATTRIBUTE_HIDDEN
189
190#endif /* !IN_LIBGCOV */
191
192#ifndef GCOV_LINKAGE
193#define GCOV_LINKAGE extern
194#endif
195
196#if IN_LIBGCOV
197#define gcov_nonruntime_assert(EXPR) ((void)(0 && (EXPR)))
198#else
199#define gcov_nonruntime_assert(EXPR) gcc_assert (EXPR)
200#define gcov_error(...) fatal_error (input_location, __VA_ARGS__)
201#endif
202
203/* File suffixes.  */
204#define GCOV_DATA_SUFFIX ".gcda"
205#define GCOV_NOTE_SUFFIX ".gcno"
206
207/* File magic. Must not be palindromes.  */
208#define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */
209#define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */
210
211/* gcov-iov.h is automatically generated by the makefile from
212   version.c, it looks like
213   	#define GCOV_VERSION ((gcov_unsigned_t)0x89abcdef)
214*/
215#include "gcov-iov.h"
216
217/* Convert a magic or version number to a 4 character string.  */
218#define GCOV_UNSIGNED2STRING(ARRAY,VALUE)	\
219  ((ARRAY)[0] = (char)((VALUE) >> 24),		\
220   (ARRAY)[1] = (char)((VALUE) >> 16),		\
221   (ARRAY)[2] = (char)((VALUE) >> 8),		\
222   (ARRAY)[3] = (char)((VALUE) >> 0))
223
224/* The record tags.  Values [1..3f] are for tags which may be in either
225   file.  Values [41..9f] for those in the note file and [a1..ff] for
226   the data file.  The tag value zero is used as an explicit end of
227   file marker -- it is not required to be present.  */
228
229#define GCOV_TAG_FUNCTION	 ((gcov_unsigned_t)0x01000000)
230#define GCOV_TAG_FUNCTION_LENGTH (3)
231#define GCOV_TAG_BLOCKS		 ((gcov_unsigned_t)0x01410000)
232#define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM)
233#define GCOV_TAG_ARCS		 ((gcov_unsigned_t)0x01430000)
234#define GCOV_TAG_ARCS_LENGTH(NUM)  (1 + (NUM) * 2)
235#define GCOV_TAG_ARCS_NUM(LENGTH)  (((LENGTH) - 1) / 2)
236#define GCOV_TAG_LINES		 ((gcov_unsigned_t)0x01450000)
237#define GCOV_TAG_COUNTER_BASE 	 ((gcov_unsigned_t)0x01a10000)
238#define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2)
239#define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2)
240#define GCOV_TAG_OBJECT_SUMMARY  ((gcov_unsigned_t)0xa1000000)
241#define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000) /* Obsolete */
242#define GCOV_TAG_SUMMARY_LENGTH (2)
243#define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000)
244#define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000)
245#define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000)
246
247
248/* Counters that are collected.  */
249
250#define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER,
251enum {
252#include "gcov-counter.def"
253GCOV_COUNTERS
254};
255#undef DEF_GCOV_COUNTER
256
257/* The first of counters used for value profiling.  They must form a
258   consecutive interval and their order must match the order of
259   HIST_TYPEs in value-prof.h.  */
260#define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTER_V_INTERVAL
261
262/* The last of counters used for value profiling.  */
263#define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1)
264
265/* Number of counters used for value profiling.  */
266#define GCOV_N_VALUE_COUNTERS \
267  (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1)
268
269/* Number of top N value histogram.  */
270#define GCOV_TOPN_VALUES 4
271
272/* Total number of single value counters.  */
273#define GCOV_TOPN_VALUES_COUNTERS (2 * GCOV_TOPN_VALUES + 1)
274
275/* Convert a counter index to a tag.  */
276#define GCOV_TAG_FOR_COUNTER(COUNT)				\
277	(GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17))
278/* Convert a tag to a counter.  */
279#define GCOV_COUNTER_FOR_TAG(TAG)					\
280	((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17))
281/* Check whether a tag is a counter tag.  */
282#define GCOV_TAG_IS_COUNTER(TAG)				\
283	(!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS)
284
285/* The tag level mask has 1's in the position of the inner levels, &
286   the lsb of the current level, and zero on the current and outer
287   levels.  */
288#define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
289
290/* Return nonzero if SUB is an immediate subtag of TAG.  */
291#define GCOV_TAG_IS_SUBTAG(TAG,SUB)				\
292	(GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) 	\
293	 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG)))
294
295/* Return nonzero if SUB is at a sublevel to TAG.  */
296#define GCOV_TAG_IS_SUBLEVEL(TAG,SUB)				\
297     	(GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
298
299/* Basic block flags.  */
300#define GCOV_BLOCK_UNEXPECTED	(1 << 1)
301
302/* Arc flags.  */
303#define GCOV_ARC_ON_TREE 	(1 << 0)
304#define GCOV_ARC_FAKE		(1 << 1)
305#define GCOV_ARC_FALLTHROUGH	(1 << 2)
306
307/* Object & program summary record.  */
308
309struct gcov_summary
310{
311  gcov_unsigned_t runs;		/* Number of program runs.  */
312  gcov_type sum_max;    	/* Sum of individual run max values.  */
313};
314
315#if !defined(inhibit_libc)
316
317/* Functions for reading and writing gcov files. In libgcov you can
318   open the file for reading then writing. Elsewhere you can open the
319   file either for reading or for writing. When reading a file you may
320   use the gcov_read_* functions, gcov_sync, gcov_position, &
321   gcov_error. When writing a file you may use the gcov_write
322   functions, gcov_seek & gcov_error. When a file is to be rewritten
323   you use the functions for reading, then gcov_rewrite then the
324   functions for writing.  Your file may become corrupted if you break
325   these invariants.  */
326
327#if !IN_LIBGCOV
328GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/);
329#endif
330
331#if !IN_LIBGCOV || defined (IN_GCOV_TOOL)
332GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t);
333#endif
334
335/* Available everywhere.  */
336GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN;
337GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN;
338GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN;
339GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN;
340GCOV_LINKAGE const char *gcov_read_string (void);
341GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/,
342			     gcov_unsigned_t /*length */);
343char *mangle_path (char const *base);
344
345#if !IN_GCOV
346/* Available outside gcov */
347GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN;
348#endif
349
350#if !IN_GCOV && !IN_LIBGCOV
351/* Available only in compiler */
352GCOV_LINKAGE void gcov_write_string (const char *);
353GCOV_LINKAGE void gcov_write_filename (const char *);
354GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t);
355GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/);
356#endif
357
358#if IN_GCOV > 0
359/* Available in gcov */
360GCOV_LINKAGE time_t gcov_time (void);
361#endif
362
363#endif /* !inhibit_libc  */
364
365#endif /* GCC_GCOV_IO_H */
366