Fix describe-function keybinding confusion
[emacs.git] / lisp / emacs-lisp / benchmark.el
blobdc1b44e31649898112cf4ef7d09c41226206d823
1 ;;; benchmark.el --- support for benchmarking code
3 ;; Copyright (C) 2003-2015 Free Software Foundation, Inc.
5 ;; Author: Dave Love <fx@gnu.org>
6 ;; Keywords: lisp, extensions
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software: you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation, either version 3 of the License, or
13 ;; (at your option) any later version.
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
23 ;;; Commentary:
25 ;; Utilities for timing the execution of forms, including the time
26 ;; taken for GC. Note that prior to timing code you may want to
27 ;; ensure things like: there has just been a GC, the relevant code is
28 ;; already loaded (so that there's no overhead from autoloading etc.),
29 ;; and the code is compiled if appropriate (but see
30 ;; `benchmark-run-compiled').
32 ;;; Code:
34 (defmacro benchmark-elapse (&rest forms)
35 "Return the time in seconds elapsed for execution of FORMS."
36 (let ((t1 (make-symbol "t1"))
37 (t2 (make-symbol "t2")))
38 `(let (,t1 ,t2)
39 (setq ,t1 (current-time))
40 ,@forms
41 (setq ,t2 (current-time))
42 (float-time (time-subtract ,t2 ,t1)))))
44 (put 'benchmark-elapse 'edebug-form-spec t)
45 (put 'benchmark-elapse 'lisp-indent-function 0)
47 ;;;###autoload
48 (defmacro benchmark-run (&optional repetitions &rest forms)
49 "Time execution of FORMS.
50 If REPETITIONS is supplied as a number, run forms that many times,
51 accounting for the overhead of the resulting loop. Otherwise run
52 FORMS once.
53 Return a list of the total elapsed time for execution, the number of
54 garbage collections that ran, and the time taken by garbage collection.
55 See also `benchmark-run-compiled'."
56 (declare (indent 1) (debug t))
57 (unless (natnump repetitions)
58 (setq forms (cons repetitions forms)
59 repetitions 1))
60 (let ((i (make-symbol "i"))
61 (gcs (make-symbol "gcs"))
62 (gc (make-symbol "gc")))
63 `(let ((,gc gc-elapsed)
64 (,gcs gcs-done))
65 (list ,(if (> repetitions 1)
66 ;; Take account of the loop overhead.
67 `(- (benchmark-elapse (dotimes (,i ,repetitions)
68 ,@forms))
69 (benchmark-elapse (dotimes (,i ,repetitions))))
70 `(benchmark-elapse ,@forms))
71 (- gcs-done ,gcs)
72 (- gc-elapsed ,gc)))))
74 ;;;###autoload
75 (defmacro benchmark-run-compiled (&optional repetitions &rest forms)
76 "Time execution of compiled version of FORMS.
77 This is like `benchmark-run', but what is timed is a funcall of the
78 byte code obtained by wrapping FORMS in a `lambda' and compiling the
79 result. The overhead of the `lambda's is accounted for."
80 (declare (indent 1) (debug t))
81 (unless (natnump repetitions)
82 (setq forms (cons repetitions forms)
83 repetitions 1))
84 (let ((i (make-symbol "i"))
85 (gcs (make-symbol "gcs"))
86 (gc (make-symbol "gc"))
87 (code (byte-compile `(lambda () ,@forms)))
88 (lambda-code (byte-compile `(lambda ()))))
89 `(let ((,gc gc-elapsed)
90 (,gcs gcs-done))
91 (list ,(if (> repetitions 1)
92 ;; Take account of the loop overhead.
93 `(- (benchmark-elapse (dotimes (,i ,repetitions)
94 (funcall ,code)))
95 (benchmark-elapse (dotimes (,i ,repetitions)
96 (funcall ,lambda-code))))
97 `(benchmark-elapse (funcall ,code)))
98 (- gcs-done ,gcs) (- gc-elapsed ,gc)))))
100 ;;;###autoload
101 (defun benchmark (repetitions form)
102 "Print the time taken for REPETITIONS executions of FORM.
103 Interactively, REPETITIONS is taken from the prefix arg.
104 For non-interactive use see also `benchmark-run' and
105 `benchmark-run-compiled'."
106 (interactive "p\nxForm: ")
107 (let ((result (eval `(benchmark-run ,repetitions ,form))))
108 (if (zerop (nth 1 result))
109 (message "Elapsed time: %fs" (car result))
110 (message "Elapsed time: %fs (%fs in %d GCs)" (car result)
111 (nth 2 result) (nth 1 result)))))
113 (provide 'benchmark)
115 ;;; benchmark.el ends here