Provided by: llvm-16_16.0.6-23ubuntu4_amd64 bug

NAME

       llvm-cov - emit coverage information

SYNOPSIS

       llvm-cov command [args…]

DESCRIPTION

       The  llvm-cov  tool  shows  code  coverage information for programs that are instrumented to emit profile
       data. It can be used to work with gcov-style coverage or with clang's instrumentation based profiling.

       If the program is invoked with a base name of gcov, it will behave as if the llvm-cov gcov  command  were
       called. Otherwise, a command should be provided.

COMMANDS

gcovshowreportexport

GCOV COMMAND

   SYNOPSIS
       llvm-cov gcov [options] SOURCEFILE

   DESCRIPTION
       The  llvm-cov  gcov  tool  reads  code  coverage  data  files and displays the coverage information for a
       specified source file. It is compatible with the gcov tool from version  4.2  of  GCC  and  may  also  be
       compatible with some later versions of gcov.

       To  use  llvm-cov  gcov,  you  must first build an instrumented version of your application that collects
       coverage data as it runs. Compile  with  the  -fprofile-arcs  and  -ftest-coverage  options  to  add  the
       instrumentation.  (Alternatively,  you  can use the --coverage option, which includes both of those other
       options.)

       At the time you compile the instrumented code, a .gcno data file will be generated for each object  file.
       These  .gcno  files  contain half of the coverage data. The other half of the data comes from .gcda files
       that are generated when you run the instrumented program, with a separate  .gcda  file  for  each  object
       file. Each time you run the program, the execution counts are summed into any existing .gcda files, so be
       sure to remove any old files if you do not want their contents to be included.

       By default, the .gcda files are written into the same directory as the object files, but you can override
       that  by  setting  the  GCOV_PREFIX  and  GCOV_PREFIX_STRIP  environment variables. The GCOV_PREFIX_STRIP
       variable specifies a number of directory components to be removed from the start of the absolute path  to
       the object file directory. After stripping those directories, the prefix from the GCOV_PREFIX variable is
       added.  These  environment  variables  allow  you  to run the instrumented program on a machine where the
       original object file directories are not accessible, but you will then need to copy the .gcda files  back
       to the object file directories where llvm-cov gcov expects to find them.

       Once  you  have  generated the coverage data files, run llvm-cov gcov for each main source file where you
       want to examine the coverage results. This should be run from the same directory where you previously ran
       the compiler. The results for the specified source file are written to a file named by appending a  .gcov
       suffix.  A separate output file is also created for each file included by the main source file, also with
       a .gcov suffix added.

       The basic content of an .gcov output file is a copy of the source file with an execution count  and  line
       number  prepended  to  every  line.  The  execution  count  is  shown as - if a line does not contain any
       executable code. If a line contains code but that code was never executed,  the  count  is  displayed  as
       #####.

   OPTIONS
       -a, --all-blocks
              Display  all  basic  blocks.  If  there are multiple blocks for a single line of source code, this
              option causes llvm-cov to show the count for each block instead of just one count for  the  entire
              line.

       -b, --branch-probabilities
              Display conditional branch probabilities and a summary of branch information.

       -c, --branch-counts
              Display branch counts instead of probabilities (requires -b).

       -m, --demangled-names
              Demangle function names.

       -f, --function-summaries
              Show  a  summary  of  coverage  for each function instead of just one summary for an entire source
              file.

       --help Display available options (–help-hidden for more).

       -l, --long-file-names
              For coverage output of files included from the main source file, add the main file  name  followed
              by  ##  as a prefix to the output file names. This can be combined with the –preserve-paths option
              to use complete paths for both the main file and the included file.

       -n, --no-output
              Do not output any .gcov files. Summary information is still displayed.

       -o <DIR|FILE>, --object-directory=<DIR>, --object-file=<FILE>
              Find objects in DIR or based on FILE’s path. If you specify a particular object file, the coverage
              data files are expected to have the same base name with .gcno and .gcda extensions. If you specify
              a directory, the files are expected in that directory with the same base name as the source file.

       -p, --preserve-paths
              Preserve path components when naming the coverage output files. In addition  to  the  source  file
              name,  include  the  directories  from  the  path  to that file. The directories are separate by #
              characters, with . directories removed and .. directories replaced by ^ characters. When used with
              the –long-file-names option, this applies to both the main file name and the included file name.

       -r     Only dump files with relative paths or absolute paths with the prefix specified by -s.

       -s <string>
              Source prefix to elide.

       -t, --stdout
              Print to stdout instead of producing .gcov files.

       -u, --unconditional-branches
              Include unconditional branches in the output for the –branch-probabilities option.

       -version
              Display the version of llvm-cov.

       -x, --hash-filenames
              Use md5 hash of file name when naming the coverage output files. The  source  file  name  will  be
              suffixed by ## followed by MD5 hash calculated for it.

   EXIT STATUS
       llvm-cov gcov returns 1 if it cannot read input files.  Otherwise, it exits with zero.

SHOW COMMAND

   SYNOPSIS
       llvm-cov show [options] -instr-profile PROFILE [BIN] [-object BIN]… [-sources] [SOURCE]…

   DESCRIPTION
       The  llvm-cov  show  command  shows  line  by  line coverage of the binaries BIN…  using the profile data
       PROFILE. It can optionally be filtered to only show the coverage for the files listed in SOURCE….

       BIN may be an executable, object file, dynamic library, or archive (thin or otherwise).

       To use llvm-cov show, you need a program that is  compiled  with  instrumentation  to  emit  profile  and
       coverage data. To build such a program with clang use the -fprofile-instr-generate and -fcoverage-mapping
       flags. If linking with the clang driver, pass -fprofile-instr-generate to the link stage to make sure the
       necessary runtime libraries are linked in.

       The coverage information is stored in the built executable or library itself, and this is what you should
       pass  to  llvm-cov  show  as  a  BIN argument. The profile data is generated by running this instrumented
       program normally. When the program exits  it  will  write  out  a  raw  profile  file,  typically  called
       default.profraw,  which  can be converted to a format that is suitable for the PROFILE argument using the
       llvm-profdata merge tool.

   OPTIONS
       -show-branches=<VIEW>
              Show coverage for branch conditions in terms of either count or percentage.  The  supported  views
              are: “count”, “percent”.

       -show-line-counts
              Show the execution counts for each line. Defaults to true, unless another -show option is used.

       -show-expansions
              Expand inclusions, such as preprocessor macros or textual inclusions, inline in the display of the
              source file. Defaults to false.

       -show-instantiations
              For  source  regions  that  are  instantiated  multiple times, such as templates in C++, show each
              instantiation separately as well as the combined summary.  Defaults to true.

       -show-regions
              Show the execution counts for each region by displaying a caret that points to the character where
              the region starts. Defaults to false.

       -show-line-counts-or-regions
              Show the execution counts for each line if there is only one region on  the  line,  but  show  the
              individual regions if there are multiple on the line.  Defaults to false.

       -use-color
              Enable or disable color output. By default this is autodetected.

       -arch=[*NAMES*]
              Specify  a  list  of  architectures  such  that  the  Nth entry in the list corresponds to the Nth
              specified binary. If the covered object is a universal binary, this specifies the architecture  to
              use.  It is an error to specify an architecture that is not included in the universal binary or to
              use an architecture that does not match a non-universal binary.

       -name=<NAME>
              Show code coverage only for functions with the given name.

       -name-allowlist=<FILE>
              Show code coverage only for functions listed in the given file. Each line in the file should start
              with allowlist_fun:, immediately followed by the name of the function to accept. This name can  be
              a wildcard expression.

       -name-regex=<PATTERN>
              Show code coverage only for functions that match the given regular expression.

       -ignore-filename-regex=<PATTERN>
              Skip source code files with file paths that match the given regular expression.

       -format=<FORMAT>
              Use the specified output format. The supported formats are: “text”, “html”.

       -tab-size=<TABSIZE>
              Replace  tabs  with <TABSIZE> spaces when preparing reports. Currently, this is only supported for
              the html format.

       -output-dir=PATH
              Specify a directory to write coverage reports into.  If  the  directory  does  not  exist,  it  is
              created.  When  used  in  function  view  mode  (i.e  when -name or -name-regex are used to select
              specific functions), the report is written to PATH/functions.EXTENSION. When  used  in  file  view
              mode, a report for each file is written to PATH/REL_PATH_TO_FILE.EXTENSION.

       -Xdemangler=<TOOL>|<TOOL-OPTION>
              Specify  a symbol demangler. This can be used to make reports more human-readable. This option can
              be specified multiple times  to  supply  arguments  to  the  demangler  (e.g  -Xdemangler  c++filt
              -Xdemangler  -n  for  C++).  The demangler is expected to read a newline-separated list of symbols
              from stdin and write a newline-separated list of the same length to stdout.

       -num-threads=N, -j=N
              Use N threads to write file reports (only applicable when -output-dir  is  specified).  When  N=0,
              llvm-cov auto-detects an appropriate number of threads to use. This is the default.

       -compilation-dir=<dir>
              Directory  used  as a base for relative coverage mapping paths. Only applicable when binaries have
              been   compiled    with    one    of    -fcoverage-prefix-map    -fcoverage-compilation-dir,    or
              -ffile-compilation-dir.

       -line-coverage-gt=<N>
              Show code coverage only for functions with line coverage greater than the given threshold.

       -line-coverage-lt=<N>
              Show code coverage only for functions with line coverage less than the given threshold.

       -region-coverage-gt=<N>
              Show code coverage only for functions with region coverage greater than the given threshold.

       -region-coverage-lt=<N>
              Show code coverage only for functions with region coverage less than the given threshold.

       -path-equivalence=<from>,<to>
              Map  the  paths  in  the coverage data to local source file paths. This allows you to generate the
              coverage data on one machine, and then use llvm-cov on a different machine where you have the same
              files on a different path.

       -coverage-watermark=<high>,<low>
              Set high and low watermarks for coverage in html format output. This allows you to  set  the  high
              and  low  watermark  of coverage as desired, green when coverage >= high, red when coverage < low,
              and yellow otherwise. Both high and low should be between 0-100 and high > low.

       -debuginfod

       Use debuginfod to look up coverage mapping for binary IDs present in the profile but not  in  any  object
       given  on  the  command  line.  Defaults  to  true  if  debuginfod  is compiled in and configured via the
       DEBUGINFOD_URLS environment variable.

       -debug-file-directory=<dir>

       Provides local directories to search for objects corresponding to binary IDs  in  the  profile  (as  with
       debuginfod). Defaults to system build ID directories.

REPORT COMMAND

   SYNOPSIS
       llvm-cov report [options] -instr-profile PROFILE [BIN] [-object BIN]… [-sources] [SOURCE]…

   DESCRIPTION
       The  llvm-cov  report  command  displays a summary of the coverage of the binaries BIN… using the profile
       data PROFILE. It can optionally be filtered to only show the coverage for the files listed in SOURCE….

       BIN may be an executable, object file, dynamic library, or archive (thin or otherwise).

       If no source files are provided, a summary line is printed for each file in the  coverage  data.  If  any
       files  are  provided, summaries can be shown for each function in the listed files if the -show-functions
       option is enabled.

       For information on compiling programs for coverage and generating profile data, see SHOW COMMAND.

   OPTIONS
       -use-color[=VALUE]
              Enable or disable color output. By default this is autodetected.

       -arch=<name>
              If the covered binary is a universal binary, select the architecture to use.  It is  an  error  to
              specify  an  architecture  that  is not included in the universal binary or to use an architecture
              that does not match a non-universal binary.

       -show-region-summary
              Show statistics for all regions. Defaults to true.

       -show-branch-summary
              Show statistics for all branch conditions. Defaults to true.

       -show-functions
              Show coverage summaries for each function. Defaults to false.

       -show-instantiation-summary
              Show statistics for all function instantiations. Defaults to false.

       -ignore-filename-regex=<PATTERN>
              Skip source code files with file paths that match the given regular expression.

       -compilation-dir=<dir>
              Directory used as a base for relative coverage mapping paths. Only applicable when  binaries  have
              been    compiled    with    one    of    -fcoverage-prefix-map    -fcoverage-compilation-dir,   or
              -ffile-compilation-dir.

       -debuginfod

       Attempt to look up coverage mapping from objects using debuginfod.  This  is  attempted  by  default  for
       binary IDs present in the profile but not provided on the command line, so long as debuginfod is compiled
       in and configured via DEBUGINFOD_URLS.

       -debug-file-directory=<dir>

       Provides a directory to search for objects corresponding to binary IDs in the profile.

EXPORT COMMAND

   SYNOPSIS
       llvm-cov export [options] -instr-profile PROFILE [BIN] [-object BIN]… [-sources] [SOURCE]…

   DESCRIPTION
       The  llvm-cov export command exports coverage data of the binaries BIN… using the profile data PROFILE in
       either JSON or lcov trace file format.

       When exporting JSON, the regions, functions, branches, expansions, and summaries  of  the  coverage  data
       will  be  exported.  When  exporting  an  lcov  trace file, the line-based coverage, branch coverage, and
       summaries will be exported.

       The exported data can optionally be filtered to only export the coverage for the files listed in SOURCE….

       For information on compiling programs for coverage and generating profile data, see SHOW COMMAND.

   OPTIONS
       -arch=<name>
              If the covered binary is a universal binary, select the architecture to use.  It is  an  error  to
              specify  an  architecture  that  is not included in the universal binary or to use an architecture
              that does not match a non-universal binary.

       -format=<FORMAT>
              Use the specified output format. The supported formats are: “text” (JSON), “lcov”.

       -summary-only
              Export only summary information for each file in the coverage data.  This  mode  will  not  export
              coverage  information  for  smaller units such as individual functions or regions. The result will
              contain the same information as produced by the llvm-cov report command, but presented in JSON  or
              lcov format rather than text.

       -ignore-filename-regex=<PATTERN>
              Skip source code files with file paths that match the given regular expression.

              -skip-expansions

              Skip exporting macro expansion coverage data.

              -skip-functions

              Skip exporting per-function coverage data.

              -num-threads=N, -j=N

              Use  N  threads  to export coverage data. When N=0, llvm-cov auto-detects an appropriate number of
              threads to use. This is the default.

       -compilation-dir=<dir>
              Directory used as a base for relative coverage mapping paths. Only applicable when  binaries  have
              been    compiled    with    one    of    -fcoverage-prefix-map    -fcoverage-compilation-dir,   or
              -ffile-compilation-dir.

       -debuginfod

       Attempt to look up coverage mapping from objects using debuginfod.  This  is  attempted  by  default  for
       binary IDs present in the profile but not provided on the command line, so long as debuginfod is compiled
       in and configured via DEBUGINFOD_URLS.

       -debug-file-directory=<dir>

       Provides a directory to search for objects corresponding to binary IDs in the profile.

AUTHOR

       Maintained by the LLVM Team (https://llvm.org/).

COPYRIGHT

       2003-2024, LLVM Project

15                                                 2024-04-14                                        LLVM-COV(1)