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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT | COLOPHON |
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GCOV-TOOL(1) GNU GCOV-TOOL(1)
gcov-tool - offline gcda profile processing tool
gcov-tool [-v|--version] [-h|--help]
gcov-tool merge [merge-options] directory1 directory2
[-o|--output directory]
[-v|--verbose]
[-w|--weight w1,w2]
gcov-tool rewrite [rewrite-options] directory
[-n|--normalize long_long_value]
[-o|--output directory]
[-s|--scale float_or_simple-frac_value]
[-v|--verbose]
gcov-tool overlap [overlap-options] directory1 directory2
[-f|--function]
[-F|--fullname]
[-h|--hotonly]
[-o|--object]
[-t|--hot_threshold] float
[-v|--verbose]
gcov-tool is an offline tool to process gcc's gcda profile files.
Current gcov-tool supports the following functionalities:
* merge two sets of profiles with weights.
* read one set of profile and rewrite profile contents. One can
scale or normalize the count values.
Examples of the use cases for this tool are:
* Collect the profiles for different set of inputs, and use
this tool to merge them. One can specify the weight to factor
in the relative importance of each input.
* Rewrite the profile after removing a subset of the gcda
files, while maintaining the consistency of the summary and
the histogram.
* It can also be used to debug or libgcov code as the tools
shares the majority code as the runtime library.
Note that for the merging operation, this profile generated
offline may contain slight different values from the online
merged profile. Here are a list of typical differences:
* histogram difference: This offline tool recomputes the
histogram after merging the counters. The resulting
histogram, therefore, is precise. The online merging does not
have this capability -- the histogram is merged from two
histograms and the result is an approximation.
* summary checksum difference: Summary checksum uses a CRC32
operation. The value depends on the link list order of gcov-
info objects. This order is different in gcov-tool from that
in the online merge. It's expected to have different summary
checksums. It does not really matter as the compiler does not
use this checksum anywhere.
* value profile counter values difference: Some counter values
for value profile are runtime dependent, like heap addresses.
It's normal to see some difference in these kind of counters.
-h
--help
Display help about using gcov-tool (on the standard output),
and exit without doing any further processing.
-v
--version
Display the gcov-tool version number (on the standard
output), and exit without doing any further processing.
merge
Merge two profile directories.
-o directory
--output directory
Set the output profile directory. Default output
directory name is merged_profile.
-v
--verbose
Set the verbose mode.
-w w1,w2
--weight w1,w2
Set the merge weights of the directory1 and directory2,
respectively. The default weights are 1 for both.
rewrite
Read the specified profile directory and rewrite to a new
directory.
-n long_long_value
--normalize <long_long_value>
Normalize the profile. The specified value is the max
counter value in the new profile.
-o directory
--output directory
Set the output profile directory. Default output name is
rewrite_profile.
-s float_or_simple-frac_value
--scale float_or_simple-frac_value
Scale the profile counters. The specified value can be in
floating point value, or simple fraction value form, such
1, 2, 2/3, and 5/3.
-v
--verbose
Set the verbose mode.
overlap
Compute the overlap score between the two specified profile
directories. The overlap score is computed based on the arc
profiles. It is defined as the sum of min (p1_counter[i] /
p1_sum_all, p2_counter[i] / p2_sum_all), for all arc counter
i, where p1_counter[i] and p2_counter[i] are two matched
counters and p1_sum_all and p2_sum_all are the sum of counter
values in profile 1 and profile 2, respectively.
-f
--function
Print function level overlap score.
-F
--fullname
Print full gcda filename.
-h
--hotonly
Only print info for hot objects/functions.
-o
--object
Print object level overlap score.
-t float
--hot_threshold <float>
Set the threshold for hot counter value.
-v
--verbose
Set the verbose mode.
gpl(7), gfdl(7), fsf-funding(7), gcc(1), gcov(1) and the Info
entry for gcc.
Copyright (c) 2014-2019 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with the Invariant Sections being "GNU General Public
License" and "Funding Free Software", the Front-Cover texts being
(a) (see below), and with the Back-Cover Texts being (b) (see
below). A copy of the license is included in the gfdl(7) man
page.
(a) The FSF's Front-Cover Text is:
A GNU Manual
(b) The FSF's Back-Cover Text is:
You have freedom to copy and modify this GNU Manual, like GNU
software. Copies published by the Free Software Foundation raise
funds for GNU development.
This page is part of the gcc (GNU Compiler Collection) project.
Information about the project can be found at
⟨http://gcc.gnu.org/⟩. If you have a bug report for this manual
page, see ⟨http://gcc.gnu.org/bugs/⟩. This page was obtained
from the tarball gcc-9.5.0.tar.xz fetched from
⟨https://ftp.fu-berlin.de/unix/languages/gcc/releases/⟩ on
2024-06-14. If you discover any rendering problems in this HTML
version of the page, or you believe there is a better or more up-
to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not
part of the original manual page), send a mail to
[email protected]
gcc-9.5.0 2022-05-27 GCOV-TOOL(1)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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