# gcov-tool-11(1) - man - phpMan

[GCOV-TOOL(1)](https://www.chedong.com/phpMan.php/man/GCOV-TOOL/1/markdown)                                     GNU                                    [GCOV-TOOL(1)](https://www.chedong.com/phpMan.php/man/GCOV-TOOL/1/markdown)



## NAME
       gcov-tool - offline gcda profile processing tool

## SYNOPSIS
       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**]

## DESCRIPTION
       **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.

## OPTIONS
### -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.

## SEE ALSO
       [**gpl**(7)](https://www.chedong.com/phpMan.php/man/gpl/7/markdown), [**gfdl**(7)](https://www.chedong.com/phpMan.php/man/gfdl/7/markdown), [**fsf-funding**(7)](https://www.chedong.com/phpMan.php/man/fsf-funding/7/markdown), [**gcc**(1)](https://www.chedong.com/phpMan.php/man/gcc/1/markdown), [**gcov**(1)](https://www.chedong.com/phpMan.php/man/gcov/1/markdown) and the Info entry for _gcc_.

## COPYRIGHT
       Copyright (c) 2014-2021 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)](https://www.chedong.com/phpMan.php/man/gfdl/7/markdown) 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.



gcc-11.4.0                                   2023-05-28                                 [GCOV-TOOL(1)](https://www.chedong.com/phpMan.php/man/GCOV-TOOL/1/markdown)
