NAME    [Toc]    [Back]

       feedback  -  Generate  an optimization feedback file using
       pixie and prof

SYNOPSIS    [Toc]    [Back]

       feedback [prof-options] [-o  feedback-file]  [-v]  objfile
       [objfile-arguments]

OPTIONS    [Toc]    [Back]

       The feedback command accepts the following prof(1) options
       and any unambiguous abbreviations: -asm, -clock megahertz,
       -{e|E}xclude  procedure_name,  -feedback filename, -heavy,
       -invocations, -lines, -merge filename, -numbers, -{o|O}nly
       procedure_name,   -procedures,   -quit  n,  -testcoverage,
       -truecycles [0,1,2], -zero.

              The feedback command ignores all other  options  in
              order to provide compatiblility with older versions
              of the feedback command.  An option  argument  following
  an  option  not recognized by this or older
              versions of the feedback command will be treated as
              the  objfile  argument.   Specifies the name of the
              feedback file. This can also be  specified  by  the
              -feedback  option of prof.  You should use only one
              of these options to specify a  feedback  file,  not
              both.  Causes the pixie, application, and prof commands
 to be printed as they are invoked.

OPERANDS    [Toc]    [Back]

       Specifies the executable of the application  for  which  a
       feedback  file  is  to be generated.  A pixie-instrumented
       version of this executable will be executed with the  current
  working  directory  and  environment variables.  The
       feedback file that is generated will reflect the  behavior
       of  one execution of the instrumented objfile. Specify the
       arguments that will cause the behavior that  you  want  to
       have optimized when the compiler uses the feedback file.

DESCRIPTION    [Toc]    [Back]

       The  feedback  command invokes pixie to add profiling code
       to an object file. The object file generated by  pixie  is
       executed  to  obtain  profiling information.  The feedback
       command then invokes prof to analyze the profiling  information.


       If  the  output of objfile needs to be redirected, but not
       the output of the feedback utility, the redirection  characters
  need to have sh(1) syntax and be within quotes. If
       objfile is multi-threaded, the LD_LIBRARY_PATH environment
       variable needs to include the current working directory.

EXAMPLES    [Toc]    [Back]

       Send  the  profiling information to the standard output: $
       feedback myprog Write a binary formatted performance  profile
  to the file myprog.feedback, which then helps a subsequent
 recompilation optimize  the  program:  $  feedback
       -feedback   myprog.feedback   myprog  $  cc  -O  -feedback
       myprog.feedback -o myprog myprog.c

FILES    [Toc]    [Back]

       Object with profiling code.  Generated  by  pixie.   Basic
       block addresses.  Generated by pixie.  Basic block counts.
       Generated by myprog.pixie.

       Note: Run pixie  and  prof  independently  if  alternative
       names are needed.

SEE ALSO    [Toc]    [Back]

       cc(1), pixie(5), prof(1)



                                                      feedback(1)