1GPROF(1) GNU GPROF(1)
2
6 gprof - display call graph profile data
7
9 gprof [ -[abcDhilLrsTvwxyz] ] [ -[ACeEfFJnNOpPqQZ][name] ]
10 [ -I dirs ] [ -d[num] ] [ -k from/to ]
11 [ -m min-count ] [ -R map_file ] [ -t table-length ]
12 [ --[no-]annotated-source[=name] ]
13 [ --[no-]exec-counts[=name] ]
14 [ --[no-]flat-profile[=name] ] [ --[no-]graph[=name] ]
15 [ --[no-]time=name] [ --all-lines ] [ --brief ]
16 [ --debug[=level] ] [ --function-ordering ]
17 [ --file-ordering map_file ] [ --directory-path=dirs ]
18 [ --display-unused-functions ] [ --file-format=name ]
19 [ --file-info ] [ --help ] [ --line ] [ --min-count=n ]
20 [ --no-static ] [ --print-path ] [ --separate-files ]
21 [ --static-call-graph ] [ --sum ] [ --table-length=len ]
22 [ --traditional ] [ --version ] [ --width=n ]
23 [ --ignore-non-functions ] [ --demangle[=STYLE] ]
24 [ --no-demangle ] [ image-file ] [ profile-file ... ]
25
27 "gprof" produces an execution profile of C, Pascal, or Fortran77 pro‐
28 grams. The effect of called routines is incorporated in the profile of
29 each caller. The profile data is taken from the call graph profile
30 file (gmon.out default) which is created by programs that are compiled
31 with the -pg option of "cc", "pc", and "f77". The -pg option also
32 links in versions of the library routines that are compiled for profil‐
33 ing. "Gprof" reads the given object file (the default is "a.out") and
34 establishes the relation between its symbol table and the call graph
35 profile from gmon.out. If more than one profile file is specified, the
36 "gprof" output shows the sum of the profile information in the given
37 profile files.
38 "Gprof" calculates the amount of time spent in each routine. Next,
40 these times are propagated along the edges of the call graph. Cycles
41 are discovered, and calls into a cycle are made to share the time of
42 the cycle.
43 Several forms of output are available from the analysis.
45 The flat profile shows how much time your program spent in each func‐
47 tion, and how many times that function was called. If you simply want
48 to know which functions burn most of the cycles, it is stated concisely
49 here.
50 The call graph shows, for each function, which functions called it,
52 which other functions it called, and how many times. There is also an
53 estimate of how much time was spent in the subroutines of each func‐
54 tion. This can suggest places where you might try to eliminate func‐
55 tion calls that use a lot of time.
56 The annotated source listing is a copy of the program's source code,
58 labeled with the number of times each line of the program was executed.
59
61 These options specify which of several output formats "gprof" should
62 produce.
63 Many of these options take an optional symspec to specify functions to
65 be included or excluded. These options can be specified multiple
66 times, with different symspecs, to include or exclude sets of symbols.
67 Specifying any of these options overrides the default (-p -q), which
69 prints a flat profile and call graph analysis for all functions.
70 "-A[symspec]"
72 "--annotated-source[=symspec]"
73 The -A option causes "gprof" to print annotated source code. If
74 symspec is specified, print output only for matching symbols.
75 "-b"
77 "--brief"
78 If the -b option is given, "gprof" doesn't print the verbose blurbs
79 that try to explain the meaning of all of the fields in the tables.
80 This is useful if you intend to print out the output, or are tired
81 of seeing the blurbs.
82 "-C[symspec]"
84 "--exec-counts[=symspec]"
85 The -C option causes "gprof" to print a tally of functions and the
86 number of times each was called. If symspec is specified, print
87 tally only for matching symbols.
88 If the profile data file contains basic-block count records, speci‐
90 fying the -l option, along with -C, will cause basic-block execu‐
91 tion counts to be tallied and displayed.
92 "-i"
94 "--file-info"
95 The -i option causes "gprof" to display summary information about
96 the profile data file(s) and then exit. The number of histogram,
97 call graph, and basic-block count records is displayed.
98 "-I dirs"
100 "--directory-path=dirs"
101 The -I option specifies a list of search directories in which to
102 find source files. Environment variable GPROF_PATH can also be
103 used to convey this information. Used mostly for annotated source
104 output.
105 "-J[symspec]"
107 "--no-annotated-source[=symspec]"
108 The -J option causes "gprof" not to print annotated source code.
109 If symspec is specified, "gprof" prints annotated source, but
110 excludes matching symbols.
111 "-L"
113 "--print-path"
114 Normally, source filenames are printed with the path component sup‐
115 pressed. The -L option causes "gprof" to print the full pathname
116 of source filenames, which is determined from symbolic debugging
117 information in the image file and is relative to the directory in
118 which the compiler was invoked.
119 "-p[symspec]"
121 "--flat-profile[=symspec]"
122 The -p option causes "gprof" to print a flat profile. If symspec
123 is specified, print flat profile only for matching symbols.
124 "-P[symspec]"
126 "--no-flat-profile[=symspec]"
127 The -P option causes "gprof" to suppress printing a flat profile.
128 If symspec is specified, "gprof" prints a flat profile, but
129 excludes matching symbols.
130 "-q[symspec]"
132 "--graph[=symspec]"
133 The -q option causes "gprof" to print the call graph analysis. If
134 symspec is specified, print call graph only for matching symbols
135 and their children.
136 "-Q[symspec]"
138 "--no-graph[=symspec]"
139 The -Q option causes "gprof" to suppress printing the call graph.
140 If symspec is specified, "gprof" prints a call graph, but excludes
141 matching symbols.
142 "-t"
144 "--table-length=num"
145 The -t option causes the num most active source lines in each
146 source file to be listed when source annotation is enabled. The
147 default is 10.
148 "-y"
150 "--separate-files"
151 This option affects annotated source output only. Normally,
152 "gprof" prints annotated source files to standard-output. If this
153 option is specified, annotated source for a file named path/file‐
154 name is generated in the file filename-ann. If the underlying file
155 system would truncate filename-ann so that it overwrites the origi‐
156 nal filename, "gprof" generates annotated source in the file file‐
157 name.ann instead (if the original file name has an extension, that
158 extension is replaced with .ann).
159 "-Z[symspec]"
161 "--no-exec-counts[=symspec]"
162 The -Z option causes "gprof" not to print a tally of functions and
163 the number of times each was called. If symspec is specified,
164 print tally, but exclude matching symbols.
165 "-r"
167 "--function-ordering"
168 The --function-ordering option causes "gprof" to print a suggested
169 function ordering for the program based on profiling data. This
170 option suggests an ordering which may improve paging, tlb and cache
171 behavior for the program on systems which support arbitrary order‐
172 ing of functions in an executable.
173 The exact details of how to force the linker to place functions in
175 a particular order is system dependent and out of the scope of this
176 manual.
177 "-R map_file"
179 "--file-ordering map_file"
180 The --file-ordering option causes "gprof" to print a suggested .o
181 link line ordering for the program based on profiling data. This
182 option suggests an ordering which may improve paging, tlb and cache
183 behavior for the program on systems which do not support arbitrary
184 ordering of functions in an executable.
185 Use of the -a argument is highly recommended with this option.
187 The map_file argument is a pathname to a file which provides func‐
189 tion name to object file mappings. The format of the file is simi‐
190 lar to the output of the program "nm".
191 c-parse.o:00000000 T yyparse
193 c-parse.o:00000004 C yyerrflag
194 c-lang.o:00000000 T maybe_objc_method_name
195 c-lang.o:00000000 T print_lang_statistics
196 c-lang.o:00000000 T recognize_objc_keyword
197 c-decl.o:00000000 T print_lang_identifier
198 c-decl.o:00000000 T print_lang_type
199 ...
200 To create a map_file with GNU "nm", type a command like "nm
202 --extern-only --defined-only -v --print-file-name program-name".
203 "-T"
205 "--traditional"
206 The -T option causes "gprof" to print its output in "traditional"
207 BSD style.
208 "-w width"
210 "--width=width"
211 Sets width of output lines to width. Currently only used when
212 printing the function index at the bottom of the call graph.
213 "-x"
215 "--all-lines"
216 This option affects annotated source output only. By default, only
217 the lines at the beginning of a basic-block are annotated. If this
218 option is specified, every line in a basic-block is annotated by
219 repeating the annotation for the first line. This behavior is sim‐
220 ilar to "tcov"'s -a.
221 "--demangle[=style]"
223 "--no-demangle"
224 These options control whether C++ symbol names should be demangled
225 when printing output. The default is to demangle symbols. The
226 "--no-demangle" option may be used to turn off demangling. Differ‐
227 ent compilers have different mangling styles. The optional deman‐
228 gling style argument can be used to choose an appropriate deman‐
229 gling style for your compiler.
230 Analysis Options
232 "-a"
234 "--no-static"
235 The -a option causes "gprof" to suppress the printing of statically
236 declared (private) functions. (These are functions whose names are
237 not listed as global, and which are not visible outside the
238 file/function/block where they were defined.) Time spent in these
239 functions, calls to/from them, etc., will all be attributed to the
240 function that was loaded directly before it in the executable file.
241 This option affects both the flat profile and the call graph.
242 "-c"
244 "--static-call-graph"
245 The -c option causes the call graph of the program to be augmented
246 by a heuristic which examines the text space of the object file and
247 identifies function calls in the binary machine code. Since normal
248 call graph records are only generated when functions are entered,
249 this option identifies children that could have been called, but
250 never were. Calls to functions that were not compiled with profil‐
251 ing enabled are also identified, but only if symbol table entries
252 are present for them. Calls to dynamic library routines are typi‐
253 cally not found by this option. Parents or children identified via
254 this heuristic are indicated in the call graph with call counts of
255 0.
256 "-D"
258 "--ignore-non-functions"
259 The -D option causes "gprof" to ignore symbols which are not known
260 to be functions. This option will give more accurate profile data
261 on systems where it is supported (Solaris and HPUX for example).
262 "-k from/to"
264 The -k option allows you to delete from the call graph any arcs
265 from symbols matching symspec from to those matching symspec to.
266 "-l"
268 "--line"
269 The -l option enables line-by-line profiling, which causes his‐
270 togram hits to be charged to individual source code lines, instead
271 of functions. If the program was compiled with basic-block count‐
272 ing enabled, this option will also identify how many times each
273 line of code was executed. While line-by-line profiling can help
274 isolate where in a large function a program is spending its time,
275 it also significantly increases the running time of "gprof", and
276 magnifies statistical inaccuracies.
277 "-m num"
279 "--min-count=num"
280 This option affects execution count output only. Symbols that are
281 executed less than num times are suppressed.
282 "-nsymspec"
284 "--time=symspec"
285 The -n option causes "gprof", in its call graph analysis, to only
286 propagate times for symbols matching symspec.
287 "-Nsymspec"
289 "--no-time=symspec"
290 The -n option causes "gprof", in its call graph analysis, not to
291 propagate times for symbols matching symspec.
292 "-z"
294 "--display-unused-functions"
295 If you give the -z option, "gprof" will mention all functions in
296 the flat profile, even those that were never called, and that had
297 no time spent in them. This is useful in conjunction with the -c
298 option for discovering which routines were never called.
299 Miscellaneous Options
301 "-d[num]"
303 "--debug[=num]"
304 The -d num option specifies debugging options. If num is not spec‐
305 ified, enable all debugging.
306 "-h"
308 "--help"
309 The -h option prints command line usage.
310 "-Oname"
312 "--file-format=name"
313 Selects the format of the profile data files. Recognized formats
314 are auto (the default), bsd, 4.4bsd, magic, and prof (not yet sup‐
315 ported).
316 "-s"
318 "--sum"
319 The -s option causes "gprof" to summarize the information in the
320 profile data files it read in, and write out a profile data file
321 called gmon.sum, which contains all the information from the pro‐
322 file data files that "gprof" read in. The file gmon.sum may be one
323 of the specified input files; the effect of this is to merge the
324 data in the other input files into gmon.sum.
325 Eventually you can run "gprof" again without -s to analyze the
327 cumulative data in the file gmon.sum.
328 "-v"
330 "--version"
331 The -v flag causes "gprof" to print the current version number, and
332 then exit.
333 Deprecated Options
335 These options have been replaced with newer versions that use sym‐
337 specs.
338 "-e function_name"
340 The -e function option tells "gprof" to not print information about
341 the function function_name (and its children...) in the call graph.
342 The function will still be listed as a child of any functions that
343 call it, but its index number will be shown as [not printed]. More
344 than one -e option may be given; only one function_name may be
345 indicated with each -e option.
346 "-E function_name"
348 The "-E function" option works like the "-e" option, but time spent
349 in the function (and children who were not called from anywhere
350 else), will not be used to compute the percentages-of-time for the
351 call graph. More than one -E option may be given; only one func‐
352 tion_name may be indicated with each -E option.
353 "-f function_name"
355 The -f function option causes "gprof" to limit the call graph to
356 the function function_name and its children (and their chil‐
357 dren...). More than one -f option may be given; only one func‐
358 tion_name may be indicated with each -f option.
359 "-F function_name"
361 The -F function option works like the "-f" option, but only time
362 spent in the function and its children (and their children...) will
363 be used to determine total-time and percentages-of-time for the
364 call graph. More than one -F option may be given; only one func‐
365 tion_name may be indicated with each -F option. The -F option
366 overrides the -E option.
367
369 "a.out"
370 the namelist and text space.
371 "gmon.out"
373 dynamic call graph and profile.
374 "gmon.sum"
376 summarized dynamic call graph and profile.
377
379 The granularity of the sampling is shown, but remains statistical at
380 best. We assume that the time for each execution of a function can be
381 expressed by the total time for the function divided by the number of
382 times the function is called. Thus the time propagated along the call
383 graph arcs to the function's parents is directly proportional to the
384 number of times that arc is traversed.
385 Parents that are not themselves profiled will have the time of their
387 profiled children propagated to them, but they will appear to be spon‐
388 taneously invoked in the call graph listing, and will not have their
389 time propagated further. Similarly, signal catchers, even though pro‐
390 filed, will appear to be spontaneous (although for more obscure rea‐
391 sons). Any profiled children of signal catchers should have their
392 times propagated properly, unless the signal catcher was invoked during
393 the execution of the profiling routine, in which case all is lost.
394 The profiled program must call "exit"(2) or return normally for the
396 profiling information to be saved in the gmon.out file.
397
399 monitor(3), profil(2), cc(1), prof(1), and the Info entry for gprof.
400 "An Execution Profiler for Modular Programs", by S. Graham, P. Kessler,
402 M. McKusick; Software - Practice and Experience, Vol. 13, pp. 671-685,
403 1983.
404 "gprof: A Call Graph Execution Profiler", by S. Graham, P. Kessler, M.
406 McKusick; Proceedings of the SIGPLAN '82 Symposium on Compiler Con‐
407 struction, SIGPLAN Notices, Vol. 17, No 6, pp. 120-126, June 1982.
408
410 Copyright (C) 1988, 92, 97, 98, 99, 2000, 2001, 2003 Free Software
411 Foundation, Inc.
412 Permission is granted to copy, distribute and/or modify this document
414 under the terms of the GNU Free Documentation License, Version 1.1 or
415 any later version published by the Free Software Foundation; with no
416 Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
417 Texts. A copy of the license is included in the section entitled "GNU
418 Free Documentation License".
419binutils-2.17.50.0.12-4 2007-04-14 GPROF(1)