man > x86_64-linux-gnu-gcov-tool-12(1)

GCOV-TOOL(1)                                     GNU                                    GCOV-TOOL(1)

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), gfdl(7), fsf-funding(7), gcc(1), gcov(1) and the Info entry for gcc.

COPYRIGHT
       Copyright (c) 2014-2022 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.

gcc-12.4.0                                   2024-06-20                                 GCOV-TOOL(1)