1LLVM-COV(1) LLVM LLVM-COV(1)
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6 llvm-cov - emit coverage information
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9 llvm-cov command [args...]
10
12 The llvm-cov tool shows code coverage information for programs that are
13 instrumented to emit profile data. It can be used to work with
14 gcov-style coverage or with clang's instrumentation based profiling.
15 If the program is invoked with a base name of gcov, it will behave as
17 if the llvm-cov gcov command were called. Otherwise, a command should
18 be provided.
19
21 • gcov
22 • show
24 • report
26 • export
28
30 SYNOPSIS
31 llvm-cov gcov [options] SOURCEFILE
32 DESCRIPTION
34 The llvm-cov gcov tool reads code coverage data files and displays the
35 coverage information for a specified source file. It is compatible with
36 the gcov tool from version 4.2 of GCC and may also be compatible with
37 some later versions of gcov.
38 To use llvm-cov gcov, you must first build an instrumented version of
40 your application that collects coverage data as it runs. Compile with
41 the -fprofile-arcs and -ftest-coverage options to add the instrumenta‐
42 tion. (Alternatively, you can use the --coverage option, which includes
43 both of those other options.) You should compile with debugging infor‐
44 mation (-g) and without optimization (-O0); otherwise, the coverage
45 data cannot be accurately mapped back to the source code.
46 At the time you compile the instrumented code, a .gcno data file will
48 be generated for each object file. These .gcno files contain half of
49 the coverage data. The other half of the data comes from .gcda files
50 that are generated when you run the instrumented program, with a sepa‐
51 rate .gcda file for each object file. Each time you run the program,
52 the execution counts are summed into any existing .gcda files, so be
53 sure to remove any old files if you do not want their contents to be
54 included.
55 By default, the .gcda files are written into the same directory as the
57 object files, but you can override that by setting the GCOV_PREFIX and
58 GCOV_PREFIX_STRIP environment variables. The GCOV_PREFIX_STRIP variable
59 specifies a number of directory components to be removed from the start
60 of the absolute path to the object file directory. After stripping
61 those directories, the prefix from the GCOV_PREFIX variable is added.
62 These environment variables allow you to run the instrumented program
63 on a machine where the original object file directories are not acces‐
64 sible, but you will then need to copy the .gcda files back to the ob‐
65 ject file directories where llvm-cov gcov expects to find them.
66 Once you have generated the coverage data files, run llvm-cov gcov for
68 each main source file where you want to examine the coverage results.
69 This should be run from the same directory where you previously ran the
70 compiler. The results for the specified source file are written to a
71 file named by appending a .gcov suffix. A separate output file is also
72 created for each file included by the main source file, also with a
73 .gcov suffix added.
74 The basic content of an .gcov output file is a copy of the source file
76 with an execution count and line number prepended to every line. The
77 execution count is shown as - if a line does not contain any executable
78 code. If a line contains code but that code was never executed, the
79 count is displayed as #####.
80 OPTIONS
82 -a, --all-blocks
83 Display all basic blocks. If there are multiple blocks for a
84 single line of source code, this option causes llvm-cov to show
85 the count for each block instead of just one count for the en‐
86 tire line.
87 -b, --branch-probabilities
89 Display conditional branch probabilities and a summary of branch
90 information.
91 -c, --branch-counts
93 Display branch counts instead of probabilities (requires -b).
94 -f, --function-summaries
96 Show a summary of coverage for each function instead of just one
97 summary for an entire source file.
98 --help Display available options (--help-hidden for more).
100 -l, --long-file-names
102 For coverage output of files included from the main source file,
103 add the main file name followed by ## as a prefix to the output
104 file names. This can be combined with the --preserve-paths op‐
105 tion to use complete paths for both the main file and the in‐
106 cluded file.
107 -n, --no-output
109 Do not output any .gcov files. Summary information is still dis‐
110 played.
111 -o=<DIR|FILE>, --object-directory=<DIR>, --object-file=<FILE>
113 Find objects in DIR or based on FILE's path. If you specify a
114 particular object file, the coverage data files are expected to
115 have the same base name with .gcno and .gcda extensions. If you
116 specify a directory, the files are expected in that directory
117 with the same base name as the source file.
118 -p, --preserve-paths
120 Preserve path components when naming the coverage output files.
121 In addition to the source file name, include the directories
122 from the path to that file. The directories are separate by #
123 characters, with . directories removed and .. directories re‐
124 placed by ^ characters. When used with the --long-file-names op‐
125 tion, this applies to both the main file name and the included
126 file name.
127 -u, --unconditional-branches
129 Include unconditional branches in the output for the
130 --branch-probabilities option.
131 -version
133 Display the version of llvm-cov.
134 -x, --hash-filenames
136 Use md5 hash of file name when naming the coverage output files.
137 The source file name will be suffixed by ## followed by MD5 hash
138 calculated for it.
139 EXIT STATUS
141 llvm-cov gcov returns 1 if it cannot read input files. Otherwise, it
142 exits with zero.
143
145 SYNOPSIS
146 llvm-cov show [options] -instr-profile PROFILE BIN [-object BIN,...]
147 [[-object BIN]] [SOURCES]
148 DESCRIPTION
150 The llvm-cov show command shows line by line coverage of the binaries
151 BIN,... using the profile data PROFILE. It can optionally be filtered
152 to only show the coverage for the files listed in SOURCES.
153 BIN may be an executable, object file, dynamic library, or archive
155 (thin or otherwise).
156 To use llvm-cov show, you need a program that is compiled with instru‐
158 mentation to emit profile and coverage data. To build such a program
159 with clang use the -fprofile-instr-generate and -fcoverage-mapping
160 flags. If linking with the clang driver, pass -fprofile-instr-generate
161 to the link stage to make sure the necessary runtime libraries are
162 linked in.
163 The coverage information is stored in the built executable or library
165 itself, and this is what you should pass to llvm-cov show as a BIN ar‐
166 gument. The profile data is generated by running this instrumented pro‐
167 gram normally. When the program exits it will write out a raw profile
168 file, typically called default.profraw, which can be converted to a
169 format that is suitable for the PROFILE argument using the llvm-prof‐
170 data merge tool.
171 OPTIONS
173 -show-line-counts
174 Show the execution counts for each line. Defaults to true, un‐
175 less another -show option is used.
176 -show-expansions
178 Expand inclusions, such as preprocessor macros or textual inclu‐
179 sions, inline in the display of the source file. Defaults to
180 false.
181 -show-instantiations
183 For source regions that are instantiated multiple times, such as
184 templates in C++, show each instantiation separately as well as
185 the combined summary. Defaults to true.
186 -show-regions
188 Show the execution counts for each region by displaying a caret
189 that points to the character where the region starts. Defaults
190 to false.
191 -show-line-counts-or-regions
193 Show the execution counts for each line if there is only one re‐
194 gion on the line, but show the individual regions if there are
195 multiple on the line. Defaults to false.
196 -use-color
198 Enable or disable color output. By default this is autodetected.
199 -arch=[*NAMES*]
201 Specify a list of architectures such that the Nth entry in the
202 list corresponds to the Nth specified binary. If the covered ob‐
203 ject is a universal binary, this specifies the architecture to
204 use. It is an error to specify an architecture that is not in‐
205 cluded in the universal binary or to use an architecture that
206 does not match a non-universal binary.
207 -name=<NAME>
209 Show code coverage only for functions with the given name.
210 -name-whitelist=<FILE>
212 Show code coverage only for functions listed in the given file.
213 Each line in the file should start with whitelist_fun:, immedi‐
214 ately followed by the name of the function to accept. This name
215 can be a wildcard expression.
216 -name-regex=<PATTERN>
218 Show code coverage only for functions that match the given regu‐
219 lar expression.
220 -ignore-filename-regex=<PATTERN>
222 Skip source code files with file paths that match the given reg‐
223 ular expression.
224 -format=<FORMAT>
226 Use the specified output format. The supported formats are:
227 "text", "html".
228 -tab-size=<TABSIZE>
230 Replace tabs with <TABSIZE> spaces when preparing reports. Cur‐
231 rently, this is only supported for the html format.
232 -output-dir=PATH
234 Specify a directory to write coverage reports into. If the di‐
235 rectory does not exist, it is created. When used in function
236 view mode (i.e when -name or -name-regex are used to select spe‐
237 cific functions), the report is written to PATH/functions.EXTEN‐
238 SION. When used in file view mode, a report for each file is
239 written to PATH/REL_PATH_TO_FILE.EXTENSION.
240 -Xdemangler=<TOOL>|<TOOL-OPTION>
242 Specify a symbol demangler. This can be used to make reports
243 more human-readable. This option can be specified multiple times
244 to supply arguments to the demangler (e.g -Xdemangler c++filt
245 -Xdemangler -n for C++). The demangler is expected to read a
246 newline-separated list of symbols from stdin and write a new‐
247 line-separated list of the same length to stdout.
248 -num-threads=N, -j=N
250 Use N threads to write file reports (only applicable when -out‐
251 put-dir is specified). When N=0, llvm-cov auto-detects an appro‐
252 priate number of threads to use. This is the default.
253 -line-coverage-gt=<N>
255 Show code coverage only for functions with line coverage greater
256 than the given threshold.
257 -line-coverage-lt=<N>
259 Show code coverage only for functions with line coverage less
260 than the given threshold.
261 -region-coverage-gt=<N>
263 Show code coverage only for functions with region coverage
264 greater than the given threshold.
265 -region-coverage-lt=<N>
267 Show code coverage only for functions with region coverage less
268 than the given threshold.
269 -path-equivalence=<from>,<to>
271 Map the paths in the coverage data to local source file paths.
272 This allows you to generate the coverage data on one machine,
273 and then use llvm-cov on a different machine where you have the
274 same files on a different path.
275
277 SYNOPSIS
278 llvm-cov report [options] -instr-profile PROFILE BIN [-object BIN,...]
279 [[-object BIN]] [SOURCES]
280 DESCRIPTION
282 The llvm-cov report command displays a summary of the coverage of the
283 binaries BIN,... using the profile data PROFILE. It can optionally be
284 filtered to only show the coverage for the files listed in SOURCES.
285 BIN may be an executable, object file, dynamic library, or archive
287 (thin or otherwise).
288 If no source files are provided, a summary line is printed for each
290 file in the coverage data. If any files are provided, summaries can be
291 shown for each function in the listed files if the -show-functions op‐
292 tion is enabled.
293 For information on compiling programs for coverage and generating pro‐
295 file data, see SHOW COMMAND.
296 OPTIONS
298 -use-color[=VALUE]
299 Enable or disable color output. By default this is autodetected.
300 -arch=<name>
302 If the covered binary is a universal binary, select the archi‐
303 tecture to use. It is an error to specify an architecture that
304 is not included in the universal binary or to use an architec‐
305 ture that does not match a non-universal binary.
306 -show-functions
308 Show coverage summaries for each function. Defaults to false.
309 -show-instantiation-summary
311 Show statistics for all function instantiations. Defaults to
312 false.
313 -ignore-filename-regex=<PATTERN>
315 Skip source code files with file paths that match the given reg‐
316 ular expression.
317
319 SYNOPSIS
320 llvm-cov export [options] -instr-profile PROFILE BIN [-object BIN,...]
321 [[-object BIN]] [SOURCES]
322 DESCRIPTION
324 The llvm-cov export command exports coverage data of the binaries
325 BIN,... using the profile data PROFILE in either JSON or lcov trace
326 file format.
327 When exporting JSON, the regions, functions, expansions, and summaries
329 of the coverage data will be exported. When exporting an lcov trace
330 file, the line-based coverage and summaries will be exported.
331 The exported data can optionally be filtered to only export the cover‐
333 age for the files listed in SOURCES.
334 For information on compiling programs for coverage and generating pro‐
336 file data, see SHOW COMMAND.
337 OPTIONS
339 -arch=<name>
340 If the covered binary is a universal binary, select the archi‐
341 tecture to use. It is an error to specify an architecture that
342 is not included in the universal binary or to use an architec‐
343 ture that does not match a non-universal binary.
344 -format=<FORMAT>
346 Use the specified output format. The supported formats are:
347 "text" (JSON), "lcov".
348 -summary-only
350 Export only summary information for each file in the coverage
351 data. This mode will not export coverage information for smaller
352 units such as individual functions or regions. The result will
353 contain the same information as produced by the llvm-cov report
354 command, but presented in JSON or lcov format rather than text.
355 -ignore-filename-regex=<PATTERN>
357 Skip source code files with file paths that match the given reg‐
358 ular expression.
359 -skip-expansions
361 Skip exporting macro expansion coverage data.
363 -skip-functions
365 Skip exporting per-function coverage data.
367 -num-threads=N, -j=N
369 Use N threads to export coverage data. When N=0, llvm-cov
371 auto-detects an appropriate number of threads to use. This is
372 the default.
373
375 Maintained by the LLVM Team (https://llvm.org/).
376
378 2003-2023, LLVM Project
37911 2023-07-20 LLVM-COV(1)