notes

来自「基于4个mips核的noc设计」· 代码 · 共 439 行 · 第 1/2 页

Sun Feb  5 16:09:16 1995

This file documents the changes and new features available with this
version of GNU gprof.

* New Features

 o Long options

 o Supports generalized file format, without breaking backward compatibility:
   new file format supports basic-block execution counts and non-realtime
   histograms (see below)

 o Supports profiling at the line level: flat profiles, call-graph profiles,
   and execution-counts can all be displayed at a level that identifies
   individual lines rather than just functions

 o Test-coverage support (similar to Sun tcov program): source files
   can be annotated with the number of times a function was invoked
   or with the number of times each basic-block in a function was
   executed

 o Generalized histograms: not just execution-time, but arbitrary
   histograms are support (for example, performance counter based
   profiles)

 o Powerful mechanism to select data to be included/excluded from
   analysis and/or output

 o Support for DEC OSF/1 v3.0

 o Full cross-platform profiling support: gprof uses BFD to support
   arbitrary, non-native object file formats and non-native byte-orders
   (this feature has not been tested yet)

 o In the call-graph function index, static function names are now
   printed together with the filename in which the function was defined
   (required bfd_find_nearest_line() support and symbolic debugging
    information to be present in the executable file)

 o Major overhaul of source code (compiles cleanly with -Wall, etc.)

* Supported Platforms

The current version is known to work on:

 o DEC OSF/1 v3.0
	All features supported.

 o SunOS 4.1.x
	All features supported.

 o Solaris 2.3
	Line-level profiling unsupported because bfd_find_nearest_line()
	is not fully implemented for Elf binaries.

 o HP-UX 9.01
	Line-level profiling unsupported because bfd_find_nearest_line()
	is not fully implemented for SOM binaries.

* Detailed Description

** User Interface Changes

The command-line interface is backwards compatible with earlier
versions of GNU gprof and Berkeley gprof.  The only exception is
the option to delete arcs from the call graph.  The old syntax
was:

	-k fromname toname

while the new syntax is:

	-k fromname/toname

This change was necessary to be compatible with long-option parsing.
Also, "fromname" and "toname" can now be arbitrary symspecs rather
than just function names (see below for an explanation of symspecs).
For example, option "-k gprof.c/" suppresses all arcs due to calls out
of file "gprof.c".

*** Sym Specs

It is often necessary to apply gprof only to specific parts of a
program.  GNU gprof has a simple but powerful mechanism to achieve
this.  So called {\em symspecs\/} provide the foundation for this
mechanism.  A symspec selects the parts of a profiled program to which
an operation should be applied to.  The syntax of a symspec is
simple:

	  filename_containing_a_dot
	| funcname_not_containing_a_dot
	| linenumber
	| ( [ any_filename ] `:' ( any_funcname | linenumber ) )

Here are some examples:

	main.c			Selects everything in file "main.c"---the
				dot in the string tells gprof to interpret
				the string as a filename, rather than as
				a function name.  To select a file whose
				name does contain a dot, a trailing colon
				should be specified.  For example, "odd:" is
				interpreted as the file named "odd".

	main			Selects all functions named "main".  Notice
				that there may be multiple instances of the
				same function name because some of the
				definitions may be local (i.e., static).
				Unless a 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, functionnames contain
				dots.  In such cases, it is necessar to
				add a leading colon to the name.  For example,
				":.mul" selects function ".mul".
				
	main.c:main		Selects function "main" in file "main.c".

	main.c:134		Selects line 134 in file "main.c".

IMPLEMENTATION NOTE: The source code uses the type sym_id for symspecs.
At some point, this probably ought to be changed to "sym_spec" to make
reading the code easier.

*** Long options

GNU gprof now supports long options.  The following is a list of all
supported options.  Options that are listed without description
operate in the same manner as the corresponding option in older
versions of gprof.

Short Form:	Long Form:
-----------	----------
-l		--line
			Request profiling at the line-level rather
			than just at the function level.  Source
			lines are identified by symbols of the form:

				func (file:line)

			where "func" is the function name, "file" is the
			file name and "line" is the line-number that
			corresponds to the line.

			To work properly, the binary must contain symbolic
			debugging information.  This means that the source
			have to be translated with option "-g" specified.
			Functions for which there is no symbolic debugging
			information available are treated as if "--line"
			had not been specified.  However, the line number
			printed with such symbols is usually incorrect
			and should be ignored.

-a		--no-static
-A[symspec]	--annotated-source[=symspec]
			Request output in the form of annotated source
			files.  If "symspec" is specified, print output only
			for symbols selected by "symspec".  If the option
			is specified multiple times, annotated output is
			generated for the union of all symspecs.

			Examples:

			  -A		Prints annotated source for all
					source files.
			  -Agprof.c	Prints annotated source for file
					gprof.c.
			  -Afoobar	Prints annotated source for files
					containing a function named "foobar".
					The entire file will be printed, but
					only the function itself will be
					annotated with profile data.

-J[symspec]	--no-annotated-source[=symspec]
			Suppress annotated source output.  If specified
			without argument, annotated output is suppressed
			completely.  With an argument, annotated output
			is suppressed only for the symbols selected by
			"symspec".  If the option is specified multiple
			times, annotated output is suppressed for the
			union of all symspecs.  This option has lower
			precedence than --annotated-source

-p[symspec]	--flat-profile[=symspec]
			Request output in the form of a flat profile
			(unless any other output-style option is specified,
			 this option is turned on by default).  If
			"symspec" is specified, include only symbols
			selected by "symspec" in flat profile.  If the
			option is specified multiple times, the flat
			profile includes symbols selected by the union
			of all symspecs.
			
-P[symspec]	--no-flat-profile[=symspec]
			Suppress output in the flat profile.  If given
			without an argument, the flat profile is suppressed
			completely.  If "symspec" is specified, suppress
			the selected symbols in the flat profile.  If the
			option is specified multiple times, the union of
			the selected symbols is suppressed.  This option
			has lower precedence than --flat-profile.

-q[symspec]	--graph[=symspec]
			Request output in the form of a call-graph
			(unless any other output-style option is specified,
			 this option is turned on by default).  If "symspec"
			is specified, include only symbols selected by
			"symspec" in the call-graph.  If the option is
			specified multiple times, the call-graph includes
			symbols selected by the union of all symspecs.

-Q[symspec]	--no-graph[=symspec]
			Suppress output in the call-graph.  If given without
			an argument, the call-graph is suppressed completely.
			With a "symspec", suppress the selected symbols
			from the call-graph.  If the option is specified
			multiple times, the union of the selected symbols
			is suppressed.  This option has lower precedence
			than --graph.