feedback(1)						      General Commands Manual						       feedback(1)

NAME

       feedback - Generate an optimization feedback file using pixie and prof

SYNOPSIS

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

OPTIONS

       The  feedback  command accepts the following prof(1) options and any unambiguous abbreviations: -asm, -clock megahertz, -{e|E}xclude proce-
       dure_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

       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 behav-
       ior  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

       The feedback command invokes pixie to add profiling code to an object file. The object file generated by pixie is executed to  obtain  pro-
       filing 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

       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

       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

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

																       feedback(1)