\input texinfo @c -*-texinfo-*-
@setfilename gprof.info
+@c Copyright 1988, 1992, 1993, 1998, 1999, 2000, 2001, 2003
+@c Free Software Foundation, Inc.
@settitle GNU gprof
@setchapternewpage odd
@ifinfo
This file documents the gprof profiler of the GNU system.
-Copyright (C) 1988, 1992, 1997, 1998 Free Software Foundation, Inc.
+@c man begin COPYRIGHT
+Copyright (C) 1988, 92, 97, 98, 99, 2000, 2001, 2003 Free Software Foundation, Inc.
-Permission is granted to make and distribute verbatim copies of
-this manual provided the copyright notice and this permission notice
-are preserved on all copies.
+Permission is granted to copy, distribute and/or modify this document
+under the terms of the GNU Free Documentation License, Version 1.1
+or any later version published by the Free Software Foundation;
+with no Invariant Sections, 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".
+
+@c man end
@ignore
Permission is granted to process this file through Tex and print the
(this paragraph not being relevant to the printed manual).
@end ignore
-Permission is granted to copy and distribute modified versions of this
-manual under the conditions for verbatim copying, provided that the entire
-resulting derived work is distributed under the terms of a permission
-notice identical to this one.
-
-Permission is granted to copy and distribute translations of this manual
-into another language, under the above conditions for modified versions.
@end ifinfo
@finalout
can use it to determine which parts of a program are taking most of the
execution time. We assume that you know how to write, compile, and
execute programs. @sc{gnu} @code{gprof} was written by Jay Fenlason.
-
-This manual was edited January 1993 by Jeffrey Osier
-and updated September 1997 by Brent Baccala.
+Eric S. Raymond made some minor corrections and additions in 2003.
@vskip 0pt plus 1filll
-Copyright @copyright{} 1988, 1992, 1997, 1998 Free Software Foundation, Inc.
-
-Permission is granted to make and distribute verbatim copies of
-this manual provided the copyright notice and this permission notice
-are preserved on all copies.
+Copyright @copyright{} 1988, 92, 97, 98, 99, 2000, 2003 Free Software Foundation, Inc.
-@ignore
-Permission is granted to process this file through TeX and print the
-results, provided the printed document carries copying permission
-notice identical to this one except for the removal of this paragraph
-(this paragraph not being relevant to the printed manual).
-
-@end ignore
-Permission is granted to copy and distribute modified versions of this
-manual under the conditions for verbatim copying, provided that the entire
-resulting derived work is distributed under the terms of a permission
-notice identical to this one.
-
-Permission is granted to copy and distribute translations of this manual
-into another language, under the same conditions as for modified versions.
+ Permission is granted to copy, distribute and/or modify this document
+ under the terms of the GNU Free Documentation License, Version 1.1
+ or any later version published by the Free Software Foundation;
+ with no Invariant Sections, 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".
@end titlepage
-@ifinfo
+@ifnottex
@node Top
@top Profiling a Program: Where Does It Spend Its Time?
execution time. We assume that you know how to write, compile, and
execute programs. @sc{gnu} @code{gprof} was written by Jay Fenlason.
-This manual was updated August 1997 by Brent Baccala.
+This document is distributed under the terms of the GNU Free
+Documentation License. A copy of the license is included in the
+section entitled "GNU Free Documentation License".
@menu
* Introduction:: What profiling means, and why it is useful.
* How do I?:: Answers to common questions
* Incompatibilities:: (between @sc{gnu} @code{gprof} and Unix @code{gprof}.)
* Details:: Details of how profiling is done
+* GNU Free Documentation License:: GNU Free Documentation License
@end menu
-@end ifinfo
+@end ifnottex
@node Introduction
@chapter Introduction to Profiling
+@ifset man
+@c man title gprof display call graph profile data
+
+@smallexample
+@c man begin SYNOPSIS
+gprof [ -[abcDhilLsTvwxyz] ] [ -[ACeEfFJnNOpPqQZ][@var{name}] ]
+ [ -I @var{dirs} ] [ -d[@var{num}] ] [ -k @var{from/to} ]
+ [ -m @var{min-count} ] [ -t @var{table-length} ]
+ [ --[no-]annotated-source[=@var{name}] ]
+ [ --[no-]exec-counts[=@var{name}] ]
+ [ --[no-]flat-profile[=@var{name}] ] [ --[no-]graph[=@var{name}] ]
+ [ --[no-]time=@var{name}] [ --all-lines ] [ --brief ]
+ [ --debug[=@var{level}] ] [ --function-ordering ]
+ [ --file-ordering ] [ --directory-path=@var{dirs} ]
+ [ --display-unused-functions ] [ --file-format=@var{name} ]
+ [ --file-info ] [ --help ] [ --line ] [ --min-count=@var{n} ]
+ [ --no-static ] [ --print-path ] [ --separate-files ]
+ [ --static-call-graph ] [ --sum ] [ --table-length=@var{len} ]
+ [ --traditional ] [ --version ] [ --width=@var{n} ]
+ [ --ignore-non-functions ] [ --demangle[=@var{STYLE}] ]
+ [ --no-demangle ] [ @var{image-file} ] [ @var{profile-file} @dots{} ]
+@c man end
+@end smallexample
+
+@c man begin DESCRIPTION
+@code{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
+(@file{gmon.out} default) which is created by programs
+that are compiled with the @samp{-pg} option of
+@code{cc}, @code{pc}, and @code{f77}.
+The @samp{-pg} option also links in versions of the library routines
+that are compiled for profiling. @code{Gprof} reads the given object
+file (the default is @code{a.out}) and establishes the relation between
+its symbol table and the call graph profile from @file{gmon.out}.
+If more than one profile file is specified, the @code{gprof}
+output shows the sum of the profile information in the given profile files.
+
+@code{Gprof} calculates the amount of time spent in each routine.
+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.
+
+@c man end
+
+@c man begin BUGS
+The granularity of the sampling is shown, but remains
+statistical at best.
+We assume that the time for each execution 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 profiled, will appear
+to be spontaneous (although for more obscure reasons).
+Any profiled children of signal catchers 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 @code{exit}(2)
+or return normally for the profiling information to be saved
+in the @file{gmon.out} file.
+@c man end
+
+@c man begin FILES
+@table @code
+@item @file{a.out}
+the namelist and text space.
+@item @file{gmon.out}
+dynamic call graph and profile.
+@item @file{gmon.sum}
+summarized dynamic call graph and profile.
+@end table
+@c man end
+
+@c man begin SEEALSO
+monitor(3), profil(2), cc(1), prof(1), and the Info entry for @file{gprof}.
+
+``An Execution Profiler for Modular Programs'',
+by S. Graham, 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.
+@c man end
+@end ifset
+
Profiling allows you to learn where your program spent its time and which
functions called which other functions while it was executing. This
information can show you which pieces of your program are slower than you
The next three chapters explain these steps in greater detail.
+@c man begin DESCRIPTION
+
Several forms of output are available from the analysis.
The @dfn{flat profile} shows how much time your program spent in each function,
The @dfn{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. @xref{Annotated Source}.
+@c man end
To better understand how profiling works, you may wish to read
a description of its implementation.
cc -o myprog myprog.c utils.c -g -pg
@end example
+Note: The @samp{-pg} option must be part of your compilation options
+as well as your link options. If it is not then no call-graph data
+will be gathered and when you run @code{gprof} you will get an error
+message like this:
+
+@example
+gprof: gmon.out file is missing call-graph data
+@end example
+
+If you add the @samp{-Q} switch to suppress the printing of the call
+graph data you will still be able to see the time samples:
+
+@example
+Flat profile:
+
+Each sample counts as 0.01 seconds.
+ % cumulative self self total
+ time seconds seconds calls Ts/call Ts/call name
+ 44.12 0.07 0.07 zazLoop
+ 35.29 0.14 0.06 main
+ 20.59 0.17 0.04 bazMillion
+
+ % the percentage of the total running time of the
+@end example
+
If you run the linker @code{ld} directly instead of through a compiler
such as @code{cc}, you may have to specify a profiling startup file
@file{gcrt0.o} as the first input file instead of the usual startup
that match program addresses to source code lines.
@xref{Line-by-line}.
-In addition to the @samp{-pg} and @samp{-g} options,
-you may also wish to specify the @samp{-a} option when compiling.
-This will instrument
-the program to perform basic-block counting. As the program runs,
+In addition to the @samp{-pg} and @samp{-g} options, older versions of
+GCC required you to specify the @samp{-a} option when compiling in
+order to instrument it to perform basic-block counting. Newer
+versions do not require this option and will not accept it;
+basic-block counting is always enabled when @samp{-pg} is on.
+
+When basic-block counting is enabled, as the program runs
it will count how many times it executed each branch of each @samp{if}
statement, each iteration of each @samp{do} loop, etc. This will
enable @code{gprof} to construct an annotated source code
listing showing how many times each line of code was executed.
+It also worth noting that GCC supports a different profiling method
+which is enabled by the @samp{-fprofile-arcs}, @samp{-ftest-coverage}
+and @samp{-fprofile-values} switches. These switches do not produce
+data which is useful to @code{gprof} however, so they are not
+discussed further here. There is also the
+@samp{-finstrument-functions} switch which will cause GCC to insert
+calls to special user supplied instrumentation routines at the entry
+and exit of every function in their program. This can be used to
+implement an alternative profiling scheme.
+
@node Executing
@chapter Executing the Program
just before exiting. If there is already a file called @file{gmon.out},
its contents are overwritten. There is currently no way to tell the
program to write the profile data under a different name, but you can rename
-the file afterward if you are concerned that it may be overwritten.
+the file afterwards if you are concerned that it may be overwritten.
In order to write the @file{gmon.out} file properly, your program must exit
normally: by returning from @code{main} or by calling @code{exit}. Calling
counts didn't get written into @file{gmon.out}.
The Perl script @code{bbconv.pl}, included with the @code{gprof}
source distribution, will convert a @file{bb.out} file into
-a format readable by @code{gprof}.
+a format readable by @code{gprof}. Invoke it like this:
+
+@smallexample
+bbconv.pl < bb.out > @var{bh-data}
+@end smallexample
+
+This translates the information in @file{bb.out} into a form that
+@code{gprof} can understand. But you still need to tell @code{gprof}
+about the existence of this translated information. To do that, include
+@var{bb-data} on the @code{gprof} command line, @emph{along with
+@file{gmon.out}}, like this:
+
+@smallexample
+gprof @var{options} @var{executable-file} gmon.out @var{bb-data} [@var{yet-more-profile-data-files}@dots{}] [> @var{outfile}]
+@end smallexample
@node Invoking
@chapter @code{gprof} Command Summary
* Output Options:: Controlling @code{gprof}'s output style
* Analysis Options:: Controlling how @code{gprof} analyses its data
* Miscellaneous Options::
-* Depricated Options:: Options you no longer need to use, but which
+* Deprecated Options:: Options you no longer need to use, but which
have been retained for compatibility
* Symspecs:: Specifying functions to include or exclude
@end menu
@node Output Options,Analysis Options,,Invoking
@section Output Options
+@c man begin OPTIONS
These options specify which of several output formats
@code{gprof} should produce.
print a tally of functions and the number of times each was called.
If @var{symspec} is specified, print tally only for matching symbols.
-If the profile data file contains basic-block count records, specifing
+If the profile data file contains basic-block count records, specifying
the @samp{-l} option, along with @samp{-C}, will cause basic-block
execution counts to be tallied and displayed.
@itemx --directory-path=@var{dirs}
The @samp{-I} option specifies a list of search directories in
which to find source files. Environment variable @var{GPROF_PATH}
-can also be used to convery this information.
+can also be used to convey this information.
Used mostly for annotated source output.
@item -J[@var{symspec}]
@item -y
@itemx --separate-files
This option affects annotated source output only.
-Normally, gprof prints annotated source files
+Normally, @code{gprof} prints annotated source files
to standard-output. If this option is specified,
-annotated source for a file named @file{path/filename}
-is generated in the file @file{filename-ann}.
+annotated source for a file named @file{path/@var{filename}}
+is generated in the file @file{@var{filename}-ann}. If the underlying
+filesystem would truncate @file{@var{filename}-ann} so that it
+overwrites the original @file{@var{filename}}, @code{gprof} generates
+annotated source in the file @file{@var{filename}.ann} instead (if the
+original file name has an extension, that extension is @emph{replaced}
+with @file{.ann}).
@item -Z[@var{symspec}]
@itemx --no-exec-counts[=@var{symspec}]
@end group
@end smallexample
-GNU @code{nm} @samp{--extern-only} @samp{--defined-only} @samp{-v} @samp{--print-file-name} can be used to create @var{map_file}.
+To create a @var{map_file} with @sc{gnu} @code{nm}, type a command like
+@kbd{nm --extern-only --defined-only -v --print-file-name program-name}.
@item -T
@itemx --traditional
a basic-block is annotated by repeating the annotation for the
first line. This behavior is similar to @code{tcov}'s @samp{-a}.
-@item --demangle
+@item --demangle[=@var{style}]
@itemx --no-demangle
These options control whether C++ symbol names should be demangled when
printing output. The default is to demangle symbols. The
-@code{--no-demangle} option may be used to turn off demangling.
-
+@code{--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.
@end table
@node Analysis Options,Miscellaneous Options,Output Options,Invoking
@end table
-@node Miscellaneous Options,Depricated Options,Analysis Options,Invoking
+@node Miscellaneous Options,Deprecated Options,Analysis Options,Invoking
@section Miscellaneous Options
@table @code
@item -O@var{name}
@itemx --file-format=@var{name}
-Selects the format of the profile data files.
-Recognized formats are @samp{auto} (the default), @samp{bsd}, @samp{magic},
-and @samp{prof} (not yet supported).
+Selects the format of the profile data files. Recognized formats are
+@samp{auto} (the default), @samp{bsd}, @samp{4.4bsd}, @samp{magic}, and
+@samp{prof} (not yet supported).
@item -s
@itemx --sum
@end table
-@node Depricated Options,Symspecs,Miscellaneous Options,Invoking
-@section Depricated Options
+@node Deprecated Options,Symspecs,Miscellaneous Options,Invoking
+@section Deprecated Options
@table @code
@end table
+@c man end
+
Note that only one function can be specified with each @code{-e},
@code{-E}, @code{-f} or @code{-F} option. To specify more than one
function, use multiple options. For example, this command:
lists in the call graph all functions that were reached from either
@code{foo} or @code{bar} and were not reachable from @code{boring}.
-@node Symspecs,,Depricated Options,Invoking
+@node Symspecs,,Deprecated Options,Invoking
@section Symspecs
Many of the output options allow functions to be included or excluded
@table @samp
@item main.c
Selects everything in file @file{main.c}---the
-dot in the string tells gprof to interpret
+dot in the string tells @code{gprof} to interpret
the string as a filename, rather than as
a function name. To select a file whose
name does not contain a dot, a trailing colon
function name is unique in a program, you must use the colon notation
explained below to specify a function from a specific source file.
-Sometimes, function names contain dots. In such cases, it is necessar
+Sometimes, function names contain dots. In such cases, it is necessary
to add a leading colon to the name. For example, @samp{:.mul} selects
function @samp{.mul}.
-In some object file formats, symbols have a leading underscore. gprof
-will normally not print these underscores. However, you must use the
-underscore when you name a symbol in a symspec. You can use the
-@code{nm} program to see whether symbols have underscores for the object
-file format you are using.
+In some object file formats, symbols have a leading underscore.
+@code{gprof} will normally not print these underscores. When you name a
+symbol in a symspec, you should type it exactly as @code{gprof} prints
+it in its output. For example, if the compiler produces a symbol
+@samp{_main} from your @code{main} function, @code{gprof} still prints
+it as @samp{main} in its output, so you should use @samp{main} in
+symspecs.
@item main.c:main
Selects function @samp{main} in file @file{main.c}.
The functions are sorted by first by decreasing run-time spent in them,
then by decreasing number of calls, then alphabetically by name. The
functions @samp{mcount} and @samp{profil} are part of the profiling
-aparatus and appear in every flat profile; their time gives a measure of
+apparatus and appear in every flat profile; their time gives a measure of
the amount of overhead due to profiling.
Just before the column headers, a statement appears indicating
The program's total execution time was 0.06
seconds, as indicated by the @samp{cumulative seconds} field. Since
each sample counted for 0.01 seconds, this means only six samples
-were taken during the run. Two of the samples occured while the
+were taken during the run. Two of the samples occurred while the
program was in the @samp{open} function, as indicated by the
@samp{self seconds} field. Each of the other four samples
-occured one each in @samp{offtime}, @samp{memccpy}, @samp{write},
+occurred one each in @samp{offtime}, @samp{memccpy}, @samp{write},
and @samp{mcount}.
Since only six samples were taken, none of these values can
be regarded as particularly reliable.
@item called
Two numbers: the number of times @code{report} was called from @code{main},
-followed by the total number of nonrecursive calls to @code{report} from
+followed by the total number of non-recursive calls to @code{report} from
all its callers.
@item name and index number
@item called
Two numbers, the number of calls to @code{report} from @code{main}
-followed by the total number of nonrecursive calls to @code{report}.
+followed by the total number of non-recursive calls to @code{report}.
This ratio is used to determine how much of @code{report}'s @code{self}
and @code{children} time gets credited to @code{main}.
@xref{Assumptions}.
first, the number of times functions in the cycle were called by functions
outside the cycle; second, the number of times they were called by
functions in the cycle (including times when a function in the cycle calls
-itself). This is a generalization of the usual split into nonrecursive and
+itself). This is a generalization of the usual split into non-recursive and
recursive calls.
The @code{calls} field of a subroutine-line for a cycle member in the
Now let's look at some of @code{gprof}'s output from the same program run,
this time with line-by-line profiling enabled. Note that @code{ct_init}'s
four histogram hits are broken down into four lines of source code - one hit
-occured on each of lines 349, 351, 382 and 385. In the call graph,
+occurred on each of lines 349, 351, 382 and 385. In the call graph,
note how
@code{ct_init}'s 13327 calls to @code{init_block} are broken down
into one call from line 396, 3071 calls from line 384, 3730 calls
Compiling with @samp{gcc @dots{} -g -pg -a} augments your program
with basic-block counting code, in addition to function counting code.
This enables @code{gprof} to determine how many times each line
-of code was exeucted.
+of code was executed.
For example, consider the following function, taken from gzip,
with line numbers added:
basic-blocks to handle various special cases.
A program augmented for basic-block counting can be analyzed with
-@code{gprof -l -A}. I also suggest use of the @samp{-x} option,
+@samp{gprof -l -A}. I also suggest use of the @samp{-x} option,
which ensures that each line of code is labeled at least once.
Here is @code{updcrc}'s
annotated source listing for a sample @code{gzip} run:
@section Estimating @code{children} Times
Some of the figures in the call graph are estimates---for example, the
-@code{children} time values and all the the time figures in caller and
+@code{children} time values and all the time figures in caller and
subroutine lines.
There is no direct information about these measurements in the profile
@chapter Answers to Common Questions
@table @asis
+@item How can I get more exact information about hot spots in my program?
+
+Looking at the per-line call counts only tells part of the story.
+Because @code{gprof} can only report call times and counts by function,
+the best way to get finer-grained information on where the program
+is spending its time is to re-factor large functions into sequences
+of calls to smaller ones. Beware however that this can introduce
+artifical hot spots since compiling with @samp{-pg} adds a significant
+overhead to function calls. An alternative solution is to use a
+non-intrusive profiler, e.g.@: oprofile.
+
@item How do I find which lines in my program were executed the most times?
Compile your program with basic-block counting enabled, run it, then
@item How do I find which lines in my program called a particular function?
-Use @code{gprof -l} and lookup the function in the call graph.
+Use @samp{gprof -l} and lookup the function in the call graph.
The callers will be broken down by function and line number.
@item How do I analyze a program that runs for less than a second?
@item
In the annotated source listing,
if there are multiple basic blocks on the same line,
-@sc{gnu} @code{gprof} prints all of their counts, seperated by commas.
+@sc{gnu} @code{gprof} prints all of their counts, separated by commas.
@ignore - it does this now
@item
@chapter Details of Profiling
@menu
-* Implementation:: How a program collets profiling information
+* Implementation:: How a program collects profiling information
* File Format:: Format of @samp{gmon.out} files
* Internals:: @code{gprof}'s internal operation
* Debugging:: Using @code{gprof}'s @samp{-d} option
both its parent routine (the child) and its parent's parent. This is
typically done by examining the stack frame to find both
the address of the child, and the return address in the original parent.
-Since this is a very machine-dependant operation, @code{mcount}
+Since this is a very machine-dependent operation, @code{mcount}
itself is typically a short assembly-language stub routine
that extracts the required
information, and then calls @code{__mcount_internal}
(a normal C function) with two arguments - @code{frompc} and @code{selfpc}.
@code{__mcount_internal} is responsible for maintaining
the in-memory call graph, which records @code{frompc}, @code{selfpc},
-and the number of times each of these call arcs was transversed.
+and the number of times each of these call arcs was traversed.
GCC Version 2 provides a magical function (@code{__builtin_return_address}),
which allows a generic @code{mcount} function to extract the
The old BSD-derived file format used for profile data does not contain a
magic cookie that allows to check whether a data file really is a
-gprof file. Furthermore, it does not provide a version number, thus
+@code{gprof} file. Furthermore, it does not provide a version number, thus
rendering changes to the file format almost impossible. @sc{gnu} @code{gprof}
uses a new file format that provides these features. For backward
compatibility, @sc{gnu} @code{gprof} continues to support the old BSD-derived
The new file format is defined in header file @file{gmon_out.h}. It
consists of a header containing the magic cookie and a version number,
as well as some spare bytes available for future extensions. All data
-in a profile data file is in the native format of the host on which
-the profile was collected. @sc{gnu} @code{gprof} adapts automatically to the
-byte-order in use.
+in a profile data file is in the native format of the target for which
+the profile was collected. @sc{gnu} @code{gprof} adapts automatically
+to the byte-order in use.
In the new file format, the header is followed by a sequence of
records. Currently, there are three different record types: histogram
verify that it is an object file,
and read its symbol table (@code{core.c:core_init}),
using @code{bfd_canonicalize_symtab} after mallocing
-an appropiate sized array of asymbols. At this point,
+an appropriately sized array of symbols. At this point,
function mappings are read (if the @samp{--file-ordering} option
has been specified), and the core text space is read into
memory (if the @samp{-c} option was given).
table - one to count the size of the symbol table required,
and the other to actually read the symbols. In between the
two passes, a single array of type @code{Sym} is created of
-the appropiate length.
+the appropriate length.
Finally, @code{symtab.c:symtab_finalize}
is called to sort the symbol table and remove duplicate entries
(entries with the same memory address).
a hit, for example.
If call graph data is present, @code{cg_arcs.c:cg_assemble} is called.
-First, if @samp{-c} was specified, a machine-dependant
+First, if @samp{-c} was specified, a machine-dependent
routine (@code{find_call}) scans through each symbol's machine code,
looking for subroutine call instructions, and adding them
to the call graph with a zero call count.
of which are assigned the same topological number.
Two passes are now made through this sorted array of symbol pointers.
The first pass, from end to beginning (parents to children),
-computes the fraction of child time to propogate to each parent
+computes the fraction of child time to propagate to each parent
and a print flag.
The print flag reflects symspec handling of INCL_GRAPH/EXCL_GRAPH,
with a parent's include or exclude (print or no print) property
being propagated to its children, unless they themselves explicitly appear
in INCL_GRAPH or EXCL_GRAPH.
A second pass, from beginning to end (children to parents) actually
-propogates the timings along the call graph, subject
+propagates the timings along the call graph, subject
to a check against INCL_TIME/EXCL_TIME.
With the print flag, fractions, and timings now stored in the symbol
structures, the topological sort array is now discarded, and a
Tracks operation of @samp{-A} option
@end table
+@node GNU Free Documentation License
+@chapter GNU Free Documentation License
+
+ GNU Free Documentation License
+
+ Version 1.1, March 2000
+
+ Copyright (C) 2000 Free Software Foundation, Inc.
+ 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+0. PREAMBLE
+
+The purpose of this License is to make a manual, textbook, or other
+written document "free" in the sense of freedom: to assure everyone
+the effective freedom to copy and redistribute it, with or without
+modifying it, either commercially or noncommercially. Secondarily,
+this License preserves for the author and publisher a way to get
+credit for their work, while not being considered responsible for
+modifications made by others.
+
+This License is a kind of "copyleft", which means that derivative
+works of the document must themselves be free in the same sense. It
+complements the GNU General Public License, which is a copyleft
+license designed for free software.
+
+We have designed this License in order to use it for manuals for free
+software, because free software needs free documentation: a free
+program should come with manuals providing the same freedoms that the
+software does. But this License is not limited to software manuals;
+it can be used for any textual work, regardless of subject matter or
+whether it is published as a printed book. We recommend this License
+principally for works whose purpose is instruction or reference.
+
+
+1. APPLICABILITY AND DEFINITIONS
+
+This License applies to any manual or other work that contains a
+notice placed by the copyright holder saying it can be distributed
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+
+2. VERBATIM COPYING
+
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+5. COMBINING DOCUMENTS
+
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+6. COLLECTIONS OF DOCUMENTS
+
+You may make a collection consisting of the Document and other documents
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+
+7. AGGREGATION WITH INDEPENDENT WORKS
+
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+8. TRANSLATION
+
+Translation is considered a kind of modification, so you may
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+Replacing Invariant Sections with translations requires special
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+
+
+9. TERMINATION
+
+You may not copy, modify, sublicense, or distribute the Document except
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+
+
+10. FUTURE REVISIONS OF THIS LICENSE
+
+The Free Software Foundation may publish new, revised versions
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+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns. See
+http://www.gnu.org/copyleft/.
+
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+
+
+ADDENDUM: How to use this License for your documents
+
+To use this License in a document you have written, include a copy of
+the License in the document and put the following copyright and
+license notices just after the title page:
+
+@smallexample
+ Copyright (c) YEAR YOUR NAME.
+ Permission is granted to copy, distribute and/or modify this document
+ under the terms of the GNU Free Documentation License, Version 1.1
+ or any later version published by the Free Software Foundation;
+ with the Invariant Sections being LIST THEIR TITLES, with the
+ Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
+ A copy of the license is included in the section entitled "GNU
+ Free Documentation License".
+@end smallexample
+
+If you have no Invariant Sections, write "with no Invariant Sections"
+instead of saying which ones are invariant. If you have no
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+"Front-Cover Texts being LIST"; likewise for Back-Cover Texts.
+
+If your document contains nontrivial examples of program code, we
+recommend releasing these examples in parallel under your choice of
+free software license, such as the GNU General Public License,
+to permit their use in free software.
+
@contents
@bye