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¶
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.) You should compile with debugging
information (
-g) and without optimization (
-O0); otherwise, the
coverage data cannot be accurately mapped back to the source code.
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).
- -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.
- -u, --unconditional-branches
- Include unconditional branches in the output for the
--branch-probabilities option.
- -version
- Display the version of llvm-cov.
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
[
SOURCES]
DESCRIPTION¶
The
llvm-cov show command shows line by line coverage of a binary
BIN using the profile data
PROFILE. It can optionally be
filtered to only show the coverage for the files listed in
SOURCES.
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 the
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-line-counts
- Show the execution counts for each line. This is enabled by default,
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.
- -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.
- -show-regions
- Show the execution counts for each region by displaying a caret that
points to the character where the region starts.
- -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.
- -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.
- -name=<NAME>
- Show code coverage only for functions with the given name.
- -name-regex=<PATTERN>
- Show code coverage only for functions that match the given regular
expression.
- -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.
REPORT COMMAND¶
SYNOPSIS¶
llvm-cov report [
options] -instr-profile
PROFILE BIN
[
SOURCES]
DESCRIPTION¶
The
llvm-cov report command displays a summary of the coverage of a
binary
BIN using the profile data
PROFILE. It can optionally be
filtered to only show the coverage for the files listed in
SOURCES.
If no source files are provided, a summary line is printed for each file in the
coverage data. If any files are provided, summaries are shown for each
function in the listed files instead.
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.
AUTHOR¶
Maintained by The LLVM Team (
http://llvm.org/).
COPYRIGHT¶
2003-2016, LLVM Project