GPROF(1)                       GNU                       GPROF(1)



NAME
       gprof - display call graph profile data

SYNOPSIS
       gprof [ -[abcDhilLsTvwxyz] ] [ -[ACeEfFJnNOpPqQZ][name] ]
        [ -I dirs ] [ -d[num] ] [ -k from/to ]
        [ -m min-count ] [ -t table-length ]
        [ --[no-]annotated-source[=name] ]
        [ --[no-]exec-counts[=name] ]
        [ --[no-]flat-profile[=name] ] [ --[no-]graph[=name] ]
        [ --[no-]time=name] [ --all-lines ] [ --brief ]
        [ --debug[=level] ] [ --function-ordering ]
        [ --file-ordering ] [ --directory-path=dirs ]
        [ --display-unused-functions ] [ --file-format=name ]
        [ --file-info ] [ --help ] [ --line ] [ --min-count=n ]
        [ --no-static ] [ --print-path ] [ --separate-files ]
        [ --static-call-graph ] [ --sum ] [ --table-length=len ]
        [ --traditional ] [ --version ] [ --width=n ]
        [ --ignore-non-functions ] [ --demangle[=STYLE] ]
        [ --no-demangle ] [ image-file ] [ profile-file ... ]

DESCRIPTION
       "gprof"  produces  an  execution  profile of C, Pascal, or
       Fortran77 programs.  The  effect  of  called  routines  is
       incorporated  in  the profile of each caller.  The profile
       data is taken from the call graph profile  file  (gmon.out
       default)  which  is  created by programs that are compiled
       with the -pg option of "cc", "pc",  and  "f77".   The  -pg
       option also links in versions of the library routines that
       are compiled  for  profiling.   "Gprof"  reads  the  given
       object  file  (the default is "a.out") and establishes the
       relation between its symbol table and the call graph  pro-
       file  from  gmon.out.   If  more  than one profile file is
       specified, the "gprof" output shows the sum of the profile
       information in the given profile files.

       "Gprof"  calculates  the amount of time spent in each rou-
       tine.  Next, these times are propagated along the edges of
       the  call  graph.  Cycles are discovered, and calls into a
       cycle are made to share the time of the cycle.

       Several forms of output are available from the analysis.

       The flat profile shows how much time your program spent in
       each  function,  and  how  many  times  that  function was
       called.  If you simply want to know which  functions  burn
       most of the cycles, it is stated concisely here.

       The  call  graph shows, for each function, which functions
       called it, which other functions it called, and  how  many
       times.   There  is  also  an estimate of how much time was
       spent in the subroutines of each function.  This can  sug-
       gest  places  where  you  might  try to eliminate function
       calls that use a lot of time.

       The annotated source listing is a copy  of  the  program's
       source code, labeled with the number of times each line of
       the program was executed.

OPTIONS
       These options specify  which  of  several  output  formats
       "gprof" should produce.

       Many  of these options take an optional symspec to specify
       functions to be included or excluded.  These  options  can
       be  specified  multiple times, with different symspecs, to
       include or exclude sets of symbols.

       Specifying any of these options overrides the default  (-p
       -q),  which  prints a flat profile and call graph analysis
       for all functions.

       "-A[symspec]"
       "--annotated-source[=symspec]"
           The -A option causes "gprof" to print annotated source
           code.   If symspec is specified, print output only for
           matching symbols.

       "-b"
       "--brief"
           If the -b option is given, "gprof" doesn't  print  the
           verbose  blurbs that try to explain the meaning of all
           of the fields in the tables.  This is  useful  if  you
           intend to print out the output, or are tired of seeing
           the blurbs.

       "-C[symspec]"
       "--exec-counts[=symspec]"
           The -C option causes "gprof" to print a tally of func-
           tions  and  the  number  of times each was called.  If
           symspec is specified, print tally  only  for  matching
           symbols.

           If  the  profile  data file contains basic-block count
           records, specifying the -l option, along with -C, will
           cause  basic-block  execution counts to be tallied and
           displayed.

       "-i"
       "--file-info"
           The -i option causes "gprof" to display summary infor-
           mation  about  the profile data file(s) and then exit.
           The number of histogram, call graph,  and  basic-block
           count records is displayed.

       "-I dirs"
       "--directory-path=dirs"
           The  -I  option specifies a list of search directories
           in which to find source files.   Environment  variable
           GPROF_PATH  can  also  be used to convey this informa-
           tion.  Used mostly for annotated source output.

       "-J[symspec]"
       "--no-annotated-source[=symspec]"
           The -J option causes "gprof" not  to  print  annotated
           source  code.  If symspec is specified, "gprof" prints
           annotated source, but excludes matching symbols.

       "-L"
       "--print-path"
           Normally, source filenames are printed with  the  path
           component suppressed.  The -L option causes "gprof" to
           print the full pathname of source filenames, which  is
           determined  from symbolic debugging information in the
           image file and is relative to the directory  in  which
           the compiler was invoked.

       "-p[symspec]"
       "--flat-profile[=symspec]"
           The  -p option causes "gprof" to print a flat profile.
           If symspec is specified, print flat profile  only  for
           matching symbols.

       "-P[symspec]"
       "--no-flat-profile[=symspec]"
           The  -P  option  causes "gprof" to suppress printing a
           flat profile.  If symspec is specified, "gprof" prints
           a flat profile, but excludes matching symbols.

       "-q[symspec]"
       "--graph[=symspec]"
           The  -q  option causes "gprof" to print the call graph
           analysis.  If symspec is specified, print  call  graph
           only for matching symbols and their children.

       "-Q[symspec]"
       "--no-graph[=symspec]"
           The  -Q option causes "gprof" to suppress printing the
           call graph.  If symspec is specified, "gprof" prints a
           call graph, but excludes matching symbols.

       "-y"
       "--separate-files"
           This  option  affects  annotated  source  output only.
           Normally, "gprof" prints  annotated  source  files  to
           standard-output.   If  this option is specified, anno-
           tated source for a file named path/filename is  gener-
           ated  in  the  file  filename-ann.   If the underlying
           filesystem would  truncate  filename-ann  so  that  it
           overwrites  the  original  filename, "gprof" generates
           annotated source in the file filename.ann instead  (if
           the  original  file name has an extension, that exten-
           sion is replaced with .ann).

       "-Z[symspec]"
       "--no-exec-counts[=symspec]"
           The -Z option causes "gprof" not to print a  tally  of
           functions and the number of times each was called.  If
           symspec is specified, print tally, but exclude  match-
           ing symbols.

       "--function-ordering"
           The --function-ordering option causes "gprof" to print
           a suggested function ordering for the program based on
           profiling  data.   This  option  suggests  an ordering
           which may improve paging, tlb and cache  behavior  for
           the  program on systems which support arbitrary order-
           ing of functions in an executable.

           The exact details of how to force the linker to  place
           functions  in  a  particular order is system dependent
           and out of the scope of this manual.

       "--file-ordering map_file"
           The --file-ordering option causes "gprof" to  print  a
           suggested  .o link line ordering for the program based
           on profiling data.  This option suggests  an  ordering
           which  may  improve paging, tlb and cache behavior for
           the program on systems which do not support  arbitrary
           ordering of functions in an executable.

           Use of the -a argument is highly recommended with this
           option.

           The map_file argument is a pathname to  a  file  which
           provides  function  name to object file mappings.  The
           format of the file is similar to  the  output  of  the
           program "nm".

                   c-parse.o:00000000 T yyparse
                   c-parse.o:00000004 C yyerrflag
                   c-lang.o:00000000 T maybe_objc_method_name
                   c-lang.o:00000000 T print_lang_statistics
                   c-lang.o:00000000 T recognize_objc_keyword
                   c-decl.o:00000000 T print_lang_identifier
                   c-decl.o:00000000 T print_lang_type
                   ...

           To  create  a  map_file  with GNU "nm", type a command
           like    "nm    --extern-only     --defined-only     -v
           --print-file-name program-name".

       "-T"
       "--traditional"
           The  -T  option  causes "gprof" to print its output in
           ``traditional'' BSD style.

       "-w width"
       "--width=width"
           Sets width of output lines to width.   Currently  only
           used when printing the function index at the bottom of
           the call graph.

       "-x"
       "--all-lines"
           This option affects annotated source output only.   By
           default,  only  the lines at the beginning of a basic-
           block are annotated.  If  this  option  is  specified,
           every  line in a basic-block is annotated by repeating
           the annotation for the first line.  This  behavior  is
           similar to "tcov"'s -a.

       "--demangle[=style]"
       "--no-demangle"
           These  options control whether C++ symbol names should
           be demangled when printing output.  The default is  to
           demangle  symbols.   The "--no-demangle" option may be
           used to turn off demangling. Different compilers  have
           different  mangling  styles.   The optional demangling
           style argument can be used to  choose  an  appropriate
           demangling style for your compiler.

       Analysis Options


       "-a"
       "--no-static"
           The  -a option causes "gprof" to suppress the printing
           of statically declared  (private)  functions.   (These
           are  functions  whose  names are not listed as global,
           and which  are  not  visible  outside  the  file/func-
           tion/block  where  they  were defined.)  Time spent in
           these functions, calls to/from them, etc, will all  be
           attributed  to  the  function that was loaded directly
           before it in the executable file.  This option affects
           both the flat profile and the call graph.

       "-c"
       "--static-call-graph"
           The  -c option causes the call graph of the program to
           be augmented by a heuristic which  examines  the  text
           space of the object file and identifies function calls
           in the binary machine code.  Since normal  call  graph
           records are only generated when functions are entered,
           this option identifies children that could  have  been
           called,  but never were.  Calls to functions that were
           not compiled with profiling enabled are  also  identi-
           fied, but only if symbol table entries are present for
           them.  Calls to dynamic library routines are typically
           not found by this option.  Parents or children identi-
           fied via this heuristic  are  indicated  in  the  call
           graph with call counts of 0.

       "-D"
       "--ignore-non-functions"
           The  -D  option causes "gprof" to ignore symbols which
           are not known to be functions.  This option will  give
           more accurate profile data on systems where it is sup-
           ported (Solaris and HPUX for example).

       "-k from/to"
           The -k option allows you to delete from the call graph
           any  arcs  from symbols matching symspec from to those
           matching symspec to.

       "-l"
       "--line"
           The -l option enables  line-by-line  profiling,  which
           causes  histogram  hits  to  be  charged to individual
           source code lines, instead of functions.  If the  pro-
           gram  was  compiled with basic-block counting enabled,
           this option will also identify  how  many  times  each
           line of code was executed.  While line-by-line profil-
           ing can help isolate where in a large function a  pro-
           gram  is  spending  its  time,  it  also significantly
           increases the running time of "gprof",  and  magnifies
           statistical inaccuracies.

       "-m num"
       "--min-count=num"
           This option affects execution count output only.  Sym-
           bols that are executed less than num  times  are  sup-
           pressed.

       "-n[symspec]"
       "--time[=symspec]"
           The -n option causes "gprof", in its call graph analy-
           sis, to only propagate times for symbols matching sym-
           spec.

       "-N[symspec]"
       "--no-time[=symspec]"
           The -n option causes "gprof", in its call graph analy-
           sis, not to propagate times for symbols matching  sym-
           spec.

       "-z"
       "--display-unused-functions"
           If  you  give  the -z option, "gprof" will mention all
           functions in the flat profile, even  those  that  were
           never  called,  and  that  had  no time spent in them.
           This is useful in conjunction with the -c  option  for
           discovering which routines were never called.




       Miscellaneous Options


       "-d[num]"
       "--debug[=num]"
           The -d num option specifies debugging options.  If num
           is not specified, enable all debugging.

       "-Oname"
       "--file-format=name"
           Selects the format of the profile data files.   Recog-
           nized  formats  are  auto  (the default), bsd, 4.4bsd,
           magic, and prof (not yet supported).

       "-s"
       "--sum"
           The -s option causes "gprof" to summarize the informa-
           tion  in  the profile data files it read in, and write
           out a profile data file called  gmon.sum,  which  con-
           tains  all the information from the profile data files
           that "gprof" read in.  The file gmon.sum may be one of
           the  specified  input  files; the effect of this is to
           merge the data in the other input files into gmon.sum.

           Eventually  you  can  run  "gprof" again without -s to
           analyze the cumulative data in the file gmon.sum.

       "-v"
       "--version"
           The -v flag causes "gprof" to print the  current  ver-
           sion number, and then exit.

       Deprecated Options

           These  options  have been replaced with newer versions
           that use symspecs.

       "-e function_name"
           The -e function option  tells  "gprof"  to  not  print
           information  about the function function_name (and its
           children...) in the call  graph.   The  function  will
           still  be listed as a child of any functions that call
           it, but  its  index  number  will  be  shown  as  [not
           printed].   More than one -e option may be given; only
           one  function_name  may  be  indicated  with  each  -e
           option.

       "-E function_name"
           The  "-E  function" option works like the "-e" option,
           but time spent in the function (and children who  were
           not  called  from  anywhere else), will not be used to
           compute the percentages-of-time for  the  call  graph.
           More  than  one -E option may be given; only one func-
           tion_name may be indicated with each -E option.

       "-f function_name"
           The -f function option causes  "gprof"  to  limit  the
           call graph to the function function_name and its chil-
           dren (and their children...).  More than one -f option
           may  be given; only one function_name may be indicated
           with each -f option.

       "-F function_name"
           The -F function option works like the "-f" option, but
           only  time spent in the function and its children (and
           their children...) will be used  to  determine  total-
           time and percentages-of-time for the call graph.  More
           than one -F  option  may  be  given;  only  one  func-
           tion_name  may  be indicated with each -F option.  The
           -F option overrides the -E option.

FILES
       "a.out"
           the namelist and text space.

       "gmon.out"
           dynamic call graph and profile.

       "gmon.sum"
           summarized dynamic call graph and profile.

BUGS
       The granularity of the sampling is shown, but remains sta-
       tistical at best.  We assume that the time for each execu-
       tion of a function can be expressed by the total time  for
       the  function  divided by the number of times the function
       is called.  Thus the time propagated along the call  graph
       arcs to the function's parents is directly proportional to
       the number of times that arc is traversed.

       Parents that are not themselves  profiled  will  have  the
       time  of  their  profiled children propagated to them, but
       they will appear to be spontaneously invoked in  the  call
       graph  listing,  and  will  not have their time propagated
       further.  Similarly, signal  catchers,  even  though  pro-
       filed,  will  appear  to be spontaneous (although for more
       obscure reasons).  Any profiled children of signal  catch-
       ers  should  have  their times propagated properly, unless
       the signal catcher was invoked during the execution of the
       profiling routine, in which case all is lost.

       The  profiled  program  must call "exit"(2) or return nor-
       mally for the profiling information to  be  saved  in  the
       gmon.out file.

SEE ALSO
       monitor(3),  profil(2), cc(1), prof(1), and the Info entry
       for gprof.

       ``An Execution Profiler for Modular Programs'', by S. Gra-
       ham,  P.  Kessler,  M.  McKusick;  Software - Practice and
       Experience, Vol. 13, pp. 671-685, 1983.

       ``gprof: A Call Graph Execution Profiler'', by S.  Graham,
       P.  Kessler,  M.  McKusick; Proceedings of the SIGPLAN '82
       Symposium on Compiler Construction, SIGPLAN Notices,  Vol.
       17, No  6, pp. 120-126, June 1982.

COPYRIGHT
       Copyright  (C) 1988, 92, 97, 98, 99, 2000, 2001, 2003 Free
       Software Foundation, Inc.

       Permission is granted to copy,  distribute  and/or  modify
       this  document  under the terms of the GNU Free Documenta-
       tion License, Version 1.1 or any later  version  published
       by  the  Free  Software Foundation; with no Invariant Sec-
       tions, with no Front-Cover Texts, and with  no  Back-Cover
       Texts.   A  copy of the license is included in the section
       entitled "GNU Free Documentation License".



binutils-2.14.91            2004-04-09                   GPROF(1)
