1llvm-cov - emit coverage information 2==================================== 3 4SYNOPSIS 5-------- 6 7:program:`llvm-cov` *command* [*args...*] 8 9DESCRIPTION 10----------- 11 12The :program:`llvm-cov` tool shows code coverage information for 13programs that are instrumented to emit profile data. It can be used to 14work with ``gcov``\-style coverage or with ``clang``\'s instrumentation 15based profiling. 16 17If the program is invoked with a base name of ``gcov``, it will behave as if 18the :program:`llvm-cov gcov` command were called. Otherwise, a command should 19be provided. 20 21COMMANDS 22-------- 23 24* :ref:`gcov <llvm-cov-gcov>` 25* :ref:`show <llvm-cov-show>` 26* :ref:`report <llvm-cov-report>` 27 28.. program:: llvm-cov gcov 29 30.. _llvm-cov-gcov: 31 32GCOV COMMAND 33------------ 34 35SYNOPSIS 36^^^^^^^^ 37 38:program:`llvm-cov gcov` [*options*] *SOURCEFILE* 39 40DESCRIPTION 41^^^^^^^^^^^ 42 43The :program:`llvm-cov gcov` tool reads code coverage data files and displays 44the coverage information for a specified source file. It is compatible with the 45``gcov`` tool from version 4.2 of ``GCC`` and may also be compatible with some 46later versions of ``gcov``. 47 48To use :program:`llvm-cov gcov`, you must first build an instrumented version 49of your application that collects coverage data as it runs. Compile with the 50``-fprofile-arcs`` and ``-ftest-coverage`` options to add the 51instrumentation. (Alternatively, you can use the ``--coverage`` option, which 52includes both of those other options.) You should compile with debugging 53information (``-g``) and without optimization (``-O0``); otherwise, the 54coverage data cannot be accurately mapped back to the source code. 55 56At the time you compile the instrumented code, a ``.gcno`` data file will be 57generated for each object file. These ``.gcno`` files contain half of the 58coverage data. The other half of the data comes from ``.gcda`` files that are 59generated when you run the instrumented program, with a separate ``.gcda`` 60file for each object file. Each time you run the program, the execution counts 61are summed into any existing ``.gcda`` files, so be sure to remove any old 62files if you do not want their contents to be included. 63 64By default, the ``.gcda`` files are written into the same directory as the 65object files, but you can override that by setting the ``GCOV_PREFIX`` and 66``GCOV_PREFIX_STRIP`` environment variables. The ``GCOV_PREFIX_STRIP`` 67variable specifies a number of directory components to be removed from the 68start of the absolute path to the object file directory. After stripping those 69directories, the prefix from the ``GCOV_PREFIX`` variable is added. These 70environment variables allow you to run the instrumented program on a machine 71where the original object file directories are not accessible, but you will 72then need to copy the ``.gcda`` files back to the object file directories 73where :program:`llvm-cov gcov` expects to find them. 74 75Once you have generated the coverage data files, run :program:`llvm-cov gcov` 76for each main source file where you want to examine the coverage results. This 77should be run from the same directory where you previously ran the 78compiler. The results for the specified source file are written to a file named 79by appending a ``.gcov`` suffix. A separate output file is also created for 80each file included by the main source file, also with a ``.gcov`` suffix added. 81 82The basic content of an ``.gcov`` output file is a copy of the source file with 83an execution count and line number prepended to every line. The execution 84count is shown as ``-`` if a line does not contain any executable code. If 85a line contains code but that code was never executed, the count is displayed 86as ``#####``. 87 88OPTIONS 89^^^^^^^ 90 91.. option:: -a, --all-blocks 92 93 Display all basic blocks. If there are multiple blocks for a single line of 94 source code, this option causes llvm-cov to show the count for each block 95 instead of just one count for the entire line. 96 97.. option:: -b, --branch-probabilities 98 99 Display conditional branch probabilities and a summary of branch information. 100 101.. option:: -c, --branch-counts 102 103 Display branch counts instead of probabilities (requires -b). 104 105.. option:: -f, --function-summaries 106 107 Show a summary of coverage for each function instead of just one summary for 108 an entire source file. 109 110.. option:: --help 111 112 Display available options (--help-hidden for more). 113 114.. option:: -l, --long-file-names 115 116 For coverage output of files included from the main source file, add the 117 main file name followed by ``##`` as a prefix to the output file names. This 118 can be combined with the --preserve-paths option to use complete paths for 119 both the main file and the included file. 120 121.. option:: -n, --no-output 122 123 Do not output any ``.gcov`` files. Summary information is still 124 displayed. 125 126.. option:: -o=<DIR|FILE>, --object-directory=<DIR>, --object-file=<FILE> 127 128 Find objects in DIR or based on FILE's path. If you specify a particular 129 object file, the coverage data files are expected to have the same base name 130 with ``.gcno`` and ``.gcda`` extensions. If you specify a directory, the 131 files are expected in that directory with the same base name as the source 132 file. 133 134.. option:: -p, --preserve-paths 135 136 Preserve path components when naming the coverage output files. In addition 137 to the source file name, include the directories from the path to that 138 file. The directories are separate by ``#`` characters, with ``.`` directories 139 removed and ``..`` directories replaced by ``^`` characters. When used with 140 the --long-file-names option, this applies to both the main file name and the 141 included file name. 142 143.. option:: -u, --unconditional-branches 144 145 Include unconditional branches in the output for the --branch-probabilities 146 option. 147 148.. option:: -version 149 150 Display the version of llvm-cov. 151 152EXIT STATUS 153^^^^^^^^^^^ 154 155:program:`llvm-cov gcov` returns 1 if it cannot read input files. Otherwise, 156it exits with zero. 157 158 159.. program:: llvm-cov show 160 161.. _llvm-cov-show: 162 163SHOW COMMAND 164------------ 165 166SYNOPSIS 167^^^^^^^^ 168 169:program:`llvm-cov show` [*options*] -instr-profile *PROFILE* *BIN* [*SOURCES*] 170 171DESCRIPTION 172^^^^^^^^^^^ 173 174The :program:`llvm-cov show` command shows line by line coverage of a binary 175*BIN* using the profile data *PROFILE*. It can optionally be filtered to only 176show the coverage for the files listed in *SOURCES*. 177 178To use :program:`llvm-cov show`, you need a program that is compiled with 179instrumentation to emit profile and coverage data. To build such a program with 180``clang`` use the ``-fprofile-instr-generate`` and ``-fcoverage-mapping`` 181flags. If linking with the ``clang`` driver, pass ``-fprofile-instr-generate`` 182to the link stage to make sure the necessary runtime libraries are linked in. 183 184The coverage information is stored in the built executable or library itself, 185and this is what you should pass to :program:`llvm-cov show` as the *BIN* 186argument. The profile data is generated by running this instrumented program 187normally. When the program exits it will write out a raw profile file, 188typically called ``default.profraw``, which can be converted to a format that 189is suitable for the *PROFILE* argument using the :program:`llvm-profdata merge` 190tool. 191 192OPTIONS 193^^^^^^^ 194 195.. option:: -show-line-counts 196 197 Show the execution counts for each line. This is enabled by default, unless 198 another ``-show`` option is used. 199 200.. option:: -show-expansions 201 202 Expand inclusions, such as preprocessor macros or textual inclusions, inline 203 in the display of the source file. 204 205.. option:: -show-instantiations 206 207 For source regions that are instantiated multiple times, such as templates in 208 ``C++``, show each instantiation separately as well as the combined summary. 209 210.. option:: -show-regions 211 212 Show the execution counts for each region by displaying a caret that points to 213 the character where the region starts. 214 215.. option:: -show-line-counts-or-regions 216 217 Show the execution counts for each line if there is only one region on the 218 line, but show the individual regions if there are multiple on the line. 219 220.. option:: -use-color[=VALUE] 221 222 Enable or disable color output. By default this is autodetected. 223 224.. option:: -arch=<name> 225 226 If the covered binary is a universal binary, select the architecture to use. 227 It is an error to specify an architecture that is not included in the 228 universal binary or to use an architecture that does not match a 229 non-universal binary. 230 231.. option:: -name=<NAME> 232 233 Show code coverage only for functions with the given name. 234 235.. option:: -name-regex=<PATTERN> 236 237 Show code coverage only for functions that match the given regular expression. 238 239.. option:: -format=<FORMAT> 240 241 Use the specified output format. The supported formats are: "text", "html". 242 243.. option:: -output-dir=PATH 244 245 Specify a directory to write coverage reports into. If the directory does not 246 exist, it is created. When used in function view mode (i.e when -name or 247 -name-regex are used to select specific functions), the report is written to 248 PATH/functions.EXTENSION. When used in file view mode, a report for each file 249 is written to PATH/REL_PATH_TO_FILE.EXTENSION. 250 251.. option:: -line-coverage-gt=<N> 252 253 Show code coverage only for functions with line coverage greater than the 254 given threshold. 255 256.. option:: -line-coverage-lt=<N> 257 258 Show code coverage only for functions with line coverage less than the given 259 threshold. 260 261.. option:: -region-coverage-gt=<N> 262 263 Show code coverage only for functions with region coverage greater than the 264 given threshold. 265 266.. option:: -region-coverage-lt=<N> 267 268 Show code coverage only for functions with region coverage less than the given 269 threshold. 270 271.. program:: llvm-cov report 272 273.. _llvm-cov-report: 274 275REPORT COMMAND 276-------------- 277 278SYNOPSIS 279^^^^^^^^ 280 281:program:`llvm-cov report` [*options*] -instr-profile *PROFILE* *BIN* [*SOURCES*] 282 283DESCRIPTION 284^^^^^^^^^^^ 285 286The :program:`llvm-cov report` command displays a summary of the coverage of a 287binary *BIN* using the profile data *PROFILE*. It can optionally be filtered to 288only show the coverage for the files listed in *SOURCES*. 289 290If no source files are provided, a summary line is printed for each file in the 291coverage data. If any files are provided, summaries are shown for each function 292in the listed files instead. 293 294For information on compiling programs for coverage and generating profile data, 295see :ref:`llvm-cov-show`. 296 297OPTIONS 298^^^^^^^ 299 300.. option:: -use-color[=VALUE] 301 302 Enable or disable color output. By default this is autodetected. 303 304.. option:: -arch=<name> 305 306 If the covered binary is a universal binary, select the architecture to use. 307 It is an error to specify an architecture that is not included in the 308 universal binary or to use an architecture that does not match a 309 non-universal binary. 310