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...]
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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.
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16 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.
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21 · gcov
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23 · show
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25 · report
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27 · export
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30 SYNOPSIS
31 llvm-cov gcov [options] SOURCEFILE
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33 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.
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39 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.
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47 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.
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56 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
65 object file directories where llvm-cov gcov expects to find them.
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67 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.
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75 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 #####.
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81 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
86 entire line.
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88 -b, --branch-probabilities
89 Display conditional branch probabilities and a summary of branch
90 information.
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92 -c, --branch-counts
93 Display branch counts instead of probabilities (requires -b).
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95 -f, --function-summaries
96 Show a summary of coverage for each function instead of just one
97 summary for an entire source file.
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99 --help Display available options (--help-hidden for more).
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101 -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
105 option to use complete paths for both the main file and the
106 included file.
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108 -n, --no-output
109 Do not output any .gcov files. Summary information is still dis‐
110 played.
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112 -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.
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119 -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
124 replaced by ^ characters. When used with the --long-file-names
125 option, this applies to both the main file name and the included
126 file name.
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128 -u, --unconditional-branches
129 Include unconditional branches in the output for the
130 --branch-probabilities option.
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132 -version
133 Display the version of llvm-cov.
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135 EXIT STATUS
136 llvm-cov gcov returns 1 if it cannot read input files. Otherwise, it
137 exits with zero.
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140 SYNOPSIS
141 llvm-cov show [options] -instr-profile PROFILE BIN [-object BIN,...]
142 [[-object BIN]] [SOURCES]
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144 DESCRIPTION
145 The llvm-cov show command shows line by line coverage of the binaries
146 BIN,... using the profile data PROFILE. It can optionally be filtered
147 to only show the coverage for the files listed in SOURCES.
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149 To use llvm-cov show, you need a program that is compiled with instru‐
150 mentation to emit profile and coverage data. To build such a program
151 with clang use the -fprofile-instr-generate and -fcoverage-mapping
152 flags. If linking with the clang driver, pass -fprofile-instr-generate
153 to the link stage to make sure the necessary runtime libraries are
154 linked in.
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156 The coverage information is stored in the built executable or library
157 itself, and this is what you should pass to llvm-cov show as a BIN
158 argument. The profile data is generated by running this instrumented
159 program normally. When the program exits it will write out a raw pro‐
160 file file, typically called default.profraw, which can be converted to
161 a format that is suitable for the PROFILE argument using the llvm-prof‐
162 data merge tool.
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164 OPTIONS
165 -show-line-counts
166 Show the execution counts for each line. This is enabled by
167 default, unless another -show option is used.
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169 -show-expansions
170 Expand inclusions, such as preprocessor macros or textual inclu‐
171 sions, inline in the display of the source file.
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173 -show-instantiations
174 For source regions that are instantiated multiple times, such as
175 templates in C++, show each instantiation separately as well as
176 the combined summary.
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178 -show-regions
179 Show the execution counts for each region by displaying a caret
180 that points to the character where the region starts.
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182 -show-line-counts-or-regions
183 Show the execution counts for each line if there is only one
184 region on the line, but show the individual regions if there are
185 multiple on the line.
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187 -use-color[=VALUE]
188 Enable or disable color output. By default this is autodetected.
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190 -arch=<name>
191 If the covered binary is a universal binary, select the archi‐
192 tecture to use. It is an error to specify an architecture that
193 is not included in the universal binary or to use an architec‐
194 ture that does not match a non-universal binary.
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196 -name=<NAME>
197 Show code coverage only for functions with the given name.
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199 -name-regex=<PATTERN>
200 Show code coverage only for functions that match the given regu‐
201 lar expression.
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203 -format=<FORMAT>
204 Use the specified output format. The supported formats are:
205 "text", "html".
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207 -tab-size=<TABSIZE>
208 Replace tabs with <TABSIZE> spaces when preparing reports. Cur‐
209 rently, this is only supported for the html format.
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211 -output-dir=PATH
212 Specify a directory to write coverage reports into. If the
213 directory does not exist, it is created. When used in function
214 view mode (i.e when -name or -name-regex are used to select spe‐
215 cific functions), the report is written to PATH/functions.EXTEN‐
216 SION. When used in file view mode, a report for each file is
217 written to PATH/REL_PATH_TO_FILE.EXTENSION.
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219 -Xdemangler=<TOOL>|<TOOL-OPTION>
220 Specify a symbol demangler. This can be used to make reports
221 more human-readable. This option can be specified multiple times
222 to supply arguments to the demangler (e.g -Xdemangler c++filt
223 -Xdemangler -n for C++). The demangler is expected to read a
224 newline-separated list of symbols from stdin and write a new‐
225 line-separated list of the same length to stdout.
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227 -num-threads=N, -j=N
228 Use N threads to write file reports (only applicable when -out‐
229 put-dir is specified). When N=0, llvm-cov auto-detects an appro‐
230 priate number of threads to use. This is the default.
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232 -line-coverage-gt=<N>
233 Show code coverage only for functions with line coverage greater
234 than the given threshold.
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236 -line-coverage-lt=<N>
237 Show code coverage only for functions with line coverage less
238 than the given threshold.
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240 -region-coverage-gt=<N>
241 Show code coverage only for functions with region coverage
242 greater than the given threshold.
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244 -region-coverage-lt=<N>
245 Show code coverage only for functions with region coverage less
246 than the given threshold.
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249 SYNOPSIS
250 llvm-cov report [options] -instr-profile PROFILE BIN [-object BIN,...]
251 [[-object BIN]] [SOURCES]
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253 DESCRIPTION
254 The llvm-cov report command displays a summary of the coverage of the
255 binaries BIN,... using the profile data PROFILE. It can optionally be
256 filtered to only show the coverage for the files listed in SOURCES.
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258 If no source files are provided, a summary line is printed for each
259 file in the coverage data. If any files are provided, summaries are
260 shown for each function in the listed files instead.
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262 For information on compiling programs for coverage and generating pro‐
263 file data, see SHOW COMMAND.
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265 OPTIONS
266 -use-color[=VALUE]
267 Enable or disable color output. By default this is autodetected.
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269 -arch=<name>
270 If the covered binary is a universal binary, select the archi‐
271 tecture to use. It is an error to specify an architecture that
272 is not included in the universal binary or to use an architec‐
273 ture that does not match a non-universal binary.
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275 -show-functions
276 Show coverage summaries for each function.
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279 SYNOPSIS
280 llvm-cov export [options] -instr-profile PROFILE BIN [-object BIN,...]
281 [[-object BIN]]
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283 DESCRIPTION
284 The llvm-cov export command exports regions, functions, expansions, and
285 summaries of the coverage of the binaries BIN,... using the profile
286 data PROFILE as JSON.
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288 For information on compiling programs for coverage and generating pro‐
289 file data, see SHOW COMMAND.
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291 OPTIONS
292 -arch=<name>
293 If the covered binary is a universal binary, select the archi‐
294 tecture to use. It is an error to specify an architecture that
295 is not included in the universal binary or to use an architec‐
296 ture that does not match a non-universal binary.
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299 Maintained by The LLVM Team (http://llvm.org/).
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302 2003-2018, LLVM Project
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3075 2018-07-14 LLVM-COV(1)