;;; -*- Mode: LISP; Package: monitor; Syntax: Common-lisp; Base: 10.;  -*-
;;; Tue Jan 25 18:32:28 1994 by Mark Kantrowitz <mkant@GLINDA.OZ.CS.CMU.EDU>

;;; ****************************************************************
;;; Metering System ************************************************
;;; ****************************************************************
;;;
;;; The Metering System is a portable Common Lisp code profiling tool.
;;; It gathers timing and consing statistics for specified functions
;;; while a program is running.
;;;
;;; The Metering System is a combination of
;;;   o  the Monitor package written by Chris McConnell
;;;   o  the Profile package written by Skef Wholey and Rob MacLachlan
;;; The two systems were merged and extended by Mark Kantrowitz.
;;;
;;; Address: Carnegie Mellon University
;;;          School of Computer Science
;;;          Pittsburgh, PA 15213
;;;
;;; This code is in the public domain and is distributed without warranty
;;; of any kind.
;;;
;;; This copy is from SLIME, http://www.common-lisp.net/project/slime/
;;;
;;;

;;; ********************************
;;; Change Log *********************
;;; ********************************
;;;
;;; 26-JUN-90  mk       Merged functionality of Monitor and Profile packages.
;;; 26-JUN-90  mk       Now handles both inclusive and exclusive statistics
;;;                     with respect to nested calls. (Allows it to subtract
;;;                     total monitoring overhead for each function, not just
;;;                     the time spent monitoring the function itself.)
;;; 26-JUN-90  mk       The table is now saved so that one may manipulate
;;;                     the data (sorting it, etc.) even after the original
;;;                     source of the data has been cleared.
;;; 25-SEP-90  mk       Added get-cons functions for Lucid 3.0, MACL 1.3.2
;;;                     required-arguments functions for Lucid 3.0,
;;;                     Franz Allegro CL, and MACL 1.3.2.
;;; 25-JAN-91  mk       Now uses fdefinition if available.
;;; 25-JAN-91  mk       Replaced (and :allegro (not :coral)) with :excl.
;;;                     Much better solution for the fact that both call
;;;                     themselves :allegro.
;;;  5-JUL-91 mk        Fixed warning to occur only when file is loaded
;;;                     uncompiled.
;;;  5-JUL-91 mk        When many unmonitored functions, print out number
;;;                     instead of whole list.
;;; 24-MAR-92 mk        Updated for CLtL2 compatibility. space measuring
;;;                     doesn't work in MCL, but fixed so that timing
;;;                     statistics do.
;;; 26-MAR-92 mk        Updated for Lispworks. Replaced :ccl with
;;;                     (and :ccl (not :lispworks)).
;;; 27-MAR-92 mk        Added get-cons for Allegro-V4.0.
;;; 01-JAN-93 mk  v2.0  Support for MCL 2.0, CMU CL 16d, Allegro V3.1/4.0/4.1,
;;;                     Lucid 4.0, ibcl
;;; 25-JAN-94 mk  v2.1  Patches for CLISP from Bruno Haible.
;;; 01-APR-05 lgorrie   Removed support for all Lisps except CLISP and OpenMCL.
;;;                     Purely to cut down on stale code (e.g. #+cltl2) in this
;;;                     version that is bundled with SLIME.
;;; 22-Aug-08 stas      Define TIME-TYPE for Clozure CL.
;;; 07-Aug-12 heller    Break lines at 80 columns
;;;

;;; ********************************
;;; To Do **************************
;;; ********************************
;;;
;;;    - Need get-cons for Allegro, AKCL.
;;;    - Speed up monitoring code. Replace use of hash tables with an embedded
;;;      offset in an array so that it will be faster than using gethash.
;;;      (i.e., svref/closure reference is usually faster than gethash).
;;;    - Beware of (get-internal-run-time) overflowing. Yikes!
;;;    - Check robustness with respect to profiled functions.
;;;    - Check logic of computing inclusive and exclusive time and consing.
;;;      Especially wrt incf/setf comment below. Should be incf, so we
;;;      sum recursive calls.
;;;    - Add option to record caller statistics -- this would list who
;;;      called which functions and how often.
;;;    - switches to turn timing/CONSING statistics collection on/off.


;;; ********************************
;;; Notes **************************
;;; ********************************
;;;
;;;    METERING has been tested (successfully) in the following lisps:
;;;       CMU Common Lisp (16d, Python Compiler 1.0 ) :new-compiler
;;;       CMU Common Lisp (M2.9 15-Aug-90, Compiler M1.8 15-Aug-90)
;;;       Macintosh Allegro Common Lisp (1.3.2)
;;;       Macintosh Common Lisp (2.0)
;;;       ExCL (Franz Allegro CL 3.1.12 [DEC 3100] 11/19/90)   :allegro-v3.1
;;;       ExCL (Franz Allegro CL 4.0.1 [Sun4] 2/8/91)          :allegro-v4.0
;;;       ExCL (Franz Allegro CL 4.1 [SPARC R1] 8/28/92 14:06) :allegro-v4.1
;;;       ExCL (Franz ACL 5.0.1 [Linux/X86] 6/29/99 16:11)     :allegro-v5.0.1
;;;       Lucid CL (Version 2.1 6-DEC-87)
;;;       Lucid Common Lisp (3.0)
;;;       Lucid Common Lisp (4.0.1 HP-700 12-Aug-91)
;;;       AKCL (1.86, June 30, 1987 or later)
;;;       Ibuki Common Lisp (Version 2, release 01.027)
;;;       CLISP (January 1994)
;;;
;;;    METERING needs to be tested in the following lisps:
;;;       Symbolics Common Lisp (8.0)
;;;       KCL (June 3, 1987 or later)
;;;       TI (Release 4.1 or later)
;;;       Golden Common Lisp (3.1 IBM-PC)
;;;       VAXLisp (2.0, 3.1)
;;;       Procyon Common Lisp


;;; ****************************************************************
;;; Documentation **************************************************
;;; ****************************************************************
;;;
;;; This system runs in any valid Common Lisp. Four small
;;; implementation-dependent changes can be made to improve performance
;;; and prettiness. In the section labelled "Implementation Dependent
;;; Changes" below, you should tailor the functions REQUIRED-ARGUMENTS,
;;; GET-CONS, GET-TIME, and TIME-UNITS-PER-SECOND to your implementation
;;; for the best results. If GET-CONS is not specified for your
;;; implementation, no consing information will be reported. The other
;;; functions will default to working forms, albeit inefficient, in
;;; non-CMU implementations. If you tailor these functions for a particular
;;; version of Common Lisp, we'd appreciate receiving the code.
;;;

;;; ****************************************************************
;;; Usage Notes ****************************************************
;;; ****************************************************************
;;;
;;; SUGGESTED USAGE:
;;;
;;; Start by monitoring big pieces of the program, then carefully choose
;;; which functions close to, but not in, the inner loop are to be
;;; monitored next. Don't monitor functions that are called by other
;;; monitored functions: you will only confuse yourself.
;;;
;;; If the per-call time reported is less than 1/10th of a second, then
;;; consider the clock resolution and profiling overhead before you believe
;;; the time. It may be that you will need to run your program many times
;;; in order to average out to a higher resolution.
;;;
;;; The easiest way to use this package is to load it and execute either
;;;     (mon:with-monitoring (names*) ()
;;;         your-forms*)
;;; or
;;;     (mon:monitor-form your-form)
;;; The former allows you to specify which functions will be monitored; the
;;; latter monitors all functions in the current package. Both automatically
;;; produce a table of statistics. Other variants can be constructed from
;;; the monitoring primitives, which are described below, along with a
;;; fuller description of these two macros.
;;;
;;; For best results, compile this file before using.
;;;
;;;
;;; CLOCK RESOLUTION:
;;;
;;; Unless you are very lucky, the length of your machine's clock "tick" is
;;; probably much longer than the time it takes a simple function to run.
;;; For example, on the IBM RT, the clock resolution is 1/50th of a second.
;;; This means that if a function is only called a few times, then only the
;;; first couple of decimal places are really meaningful.
;;;
;;;
;;; MONITORING OVERHEAD:
;;;
;;; The added monitoring code takes time to run every time that the monitored
;;; function is called, which can disrupt the attempt to collect timing
;;; information. In order to avoid serious inflation of the times for functions
;;; that take little time to run, an estimate of the overhead due to monitoring
;;; is subtracted from the times reported for each function.
;;;
;;; Although this correction works fairly well, it is not totally accurate,
;;; resulting in times that become increasingly meaningless for functions
;;; with short runtimes. For example, subtracting the estimated overhead
;;; may result in negative times for some functions. This is only a concern
;;; when the estimated profiling overhead is many times larger than
;;; reported total CPU time.
;;;
;;; If you monitor functions that are called by monitored functions, in
;;; :inclusive mode the monitoring overhead for the inner function is
;;; subtracted from the CPU time for the outer function. [We do this by
;;; counting for each function not only the number of calls to *this*
;;; function, but also the number of monitored calls while it was running.]
;;; In :exclusive mode this is not necessary, since we subtract the
;;; monitoring time of inner functions, overhead & all.
;;;
;;; Otherwise, the estimated monitoring overhead is not represented in the
;;; reported total CPU time. The sum of total CPU time and the estimated
;;; monitoring overhead should be close to the total CPU time for the
;;; entire monitoring run (as determined by TIME).
;;;
;;; A timing overhead factor is computed at load time. This will be incorrect
;;; if the monitoring code is run in a different environment than this file
;;; was loaded in. For example, saving a core image on a high performance
;;; machine and running it on a low performance one will result in the use
;;; of an erroneously small overhead factor.
;;;
;;;
;;; If your times vary widely, possible causes are:
;;;    - Garbage collection.  Try turning it off, then running your code.
;;;      Be warned that monitoring code will probably cons when it does
;;;      (get-internal-run-time).
;;;    - Swapping.  If you have enough memory, execute your form once
;;;      before monitoring so that it will be swapped into memory. Otherwise,
;;;      get a bigger machine!
;;;    - Resolution of internal-time-units-per-second.  If this value is
;;;      too low, then the timings become wild. You can try executing more
;;;      of whatever your test is, but that will only work if some of your
;;;      paths do not match the timer resolution.
;;;      internal-time-units-per-second is so coarse -- on a Symbolics it is
;;;      977, in MACL it is 60.
;;;
;;;

;;; ****************************************************************
;;; Interface ******************************************************
;;; ****************************************************************
;;;
;;; WITH-MONITORING (&rest functions)                         [Macro]
;;;                 (&optional (nested :exclusive)
;;;                            (threshold 0.01)
;;;                            (key :percent-time))
;;;                 &body body
;;; The named functions will be set up for monitoring, the body forms executed,
;;; a table of results printed, and the functions unmonitored. The nested,
;;; threshold, and key arguments are passed to report-monitoring below.
;;;
;;; MONITOR-FORM form                                         [Macro]
;;;               &optional (nested :exclusive)
;;;                         (threshold 0.01)
;;;                         (key :percent-time)
;;; All functions in the current package are set up for monitoring while
;;; the form is executed, and automatically unmonitored after a table of
;;; results has been printed. The nested, threshold, and key arguments
;;; are passed to report-monitoring below.
;;;
;;; *MONITORED-FUNCTIONS*                                     [Variable]
;;; This holds a list of all functions that are currently being monitored.
;;;
;;; MONITOR &rest names                                       [Macro]
;;; The named functions will be set up for monitoring by augmenting
;;; their function definitions with code that gathers statistical information
;;; about code performance. As with the TRACE macro, the function names are
;;; not evaluated. Calls the function MON::MONITORING-ENCAPSULATE on each
;;; function name. If no names are specified, returns a list of all
;;; monitored functions.
;;;
;;; If name is not a symbol, it is evaled to return the appropriate
;;; closure. This allows you to monitor closures stored anywhere like
;;; in a variable, array or structure. Most other monitoring packages
;;; can't handle this.
;;;
;;; MONITOR-ALL &optional (package *package*)                 [Function]
;;; Monitors all functions in the specified package, which defaults to
;;; the current package.
;;;
;;; UNMONITOR &rest names                                     [Macro]
;;; Removes monitoring code from the named functions. If no names are
;;; specified, all currently monitored functions are unmonitored.
;;;
;;; RESET-MONITORING-INFO name                                [Function]
;;; Resets the monitoring statistics for the specified function.
;;;
;;; RESET-ALL-MONITORING                                      [Function]
;;; Resets the monitoring statistics for all monitored functions.
;;;
;;; MONITORED name                                            [Function]
;;; Predicate to test whether a function is monitored.
;;;
;;; REPORT-MONITORING &optional names                         [Function]
;;;                             (nested :exclusive)
;;;                             (threshold 0.01)
;;;                             (key :percent-time)
;;; Creates a table of monitoring information for the specified list
;;; of names, and displays the table using display-monitoring-results.
;;; If names is :all or nil, uses all currently monitored functions.
;;; Takes the following arguments:
;;;    - NESTED specifies whether nested calls of monitored functions
;;;      are included in the times for monitored functions.
;;;      o  If :inclusive, the per-function information is for the entire
;;;         duration of the monitored function, including any calls to
;;;         other monitored functions. If functions A and B are monitored,
;;;         and A calls B, then the accumulated time and consing for A will
;;;         include the time and consing of B.  Note: if a function calls
;;;         itself recursively, the time spent in the inner call(s) may
;;;         be counted several times.
;;;      o  If :exclusive, the information excludes time attributed to
;;;         calls to other monitored functions. This is the default.
;;;    - THRESHOLD specifies that only functions which have been executed
;;;      more than threshold percent of the time will be reported. Defaults
;;;      to 1%. If a threshold of 0 is specified, all functions are listed,
;;;      even those with 0 or negative running times (see note on overhead).
;;;    - KEY specifies that the table be sorted by one of the following
;;;      sort keys:
;;;         :function       alphabetically by function name
;;;         :percent-time   by percent of total execution time
;;;         :percent-cons   by percent of total consing
;;;         :calls          by number of times the function was called
;;;         :time-per-call  by average execution time per function
;;;         :cons-per-call  by average consing per function
;;;         :time           same as :percent-time
;;;         :cons           same as :percent-cons
;;;
;;; REPORT &key (names :all)                                  [Function]
;;;             (nested :exclusive)
;;;             (threshold 0.01)
;;;             (sort-key :percent-time)
;;;             (ignore-no-calls nil)
;;;
;;; Same as REPORT-MONITORING but we use a nicer keyword interface.
;;;
;;; DISPLAY-MONITORING-RESULTS &optional (threshold 0.01)     [Function]
;;;                                      (key :percent-time)
;;; Prints a table showing for each named function:
;;;    - the total CPU time used in that function for all calls
;;;    - the total number of bytes consed in that function for all calls
;;;    - the total number of calls
;;;    - the average amount of CPU time per call
;;;    - the average amount of consing per call
;;;    - the percent of total execution time spent executing that function
;;;    - the percent of total consing spent consing in that function
;;; Summary totals of the CPU time, consing, and calls columns are printed.
;;; An estimate of the monitoring overhead is also printed. May be run
;;; even after unmonitoring all the functions, to play with the data.
;;;
;;; SAMPLE TABLE:
#|
                                               Cons
                 %     %                       Per      Total   Total
Function         Time  Cons  Calls  Sec/Call   Call     Time    Cons
----------------------------------------------------------------------
FIND-ROLE:       0.58  0.00    136  0.003521      0  0.478863       0
GROUP-ROLE:      0.35  0.00    365  0.000802      0  0.292760       0
GROUP-PROJECTOR: 0.05  0.00    102  0.000408      0  0.041648       0
FEATURE-P:       0.02  0.00    570  0.000028      0  0.015680       0
----------------------------------------------------------------------
TOTAL:                        1173                   0.828950       0
Estimated total monitoring overhead: 0.88 seconds
|#

;;; ****************************************************************
;;; METERING *******************************************************
;;; ****************************************************************

;;; ********************************
;;; Warn people using the wrong Lisp
;;; ********************************

#-(or clisp openmcl)
(warn "metering.lisp does not support your Lisp implementation!")

;;; ********************************
;;; Packages ***********************
;;; ********************************

;;; For CLtL2 compatible lisps

(defpackage "MONITOR" (:nicknames "MON") (:use "COMMON-LISP")
  (:export "*MONITORED-FUNCTIONS*"
	   "MONITOR" "MONITOR-ALL" "UNMONITOR" "MONITOR-FORM"
	   "WITH-MONITORING"
	   "RESET-MONITORING-INFO" "RESET-ALL-MONITORING"
	   "MONITORED"
	   "REPORT-MONITORING"
	   "DISPLAY-MONITORING-RESULTS"
	   "MONITORING-ENCAPSULATE" "MONITORING-UNENCAPSULATE"
	   "REPORT"))
(in-package "MONITOR")

;;; Warn user if they're loading the source instead of compiling it first.
(eval-when (eval)
   (warn "This file should be compiled before loading for best results."))

;;; ********************************
;;; Version ************************
;;; ********************************

(defparameter *metering-version* "v2.1 25-JAN-94"
  "Current version number/date for Metering.")


;;; ****************************************************************
;;; Implementation Dependent Definitions ***************************
;;; ****************************************************************

;;; ********************************
;;; Timing Functions ***************
;;; ********************************
;;; The get-time function is called to find the total number of ticks since
;;; the beginning of time. time-units-per-second allows us to convert units
;;; to seconds.

#-(or clisp openmcl)
(eval-when (compile eval)
  (warn
   "You may want to supply implementation-specific get-time functions."))

(defconstant time-units-per-second internal-time-units-per-second)

#+openmcl
(progn
 (deftype time-type () 'unsigned-byte)
 (deftype consing-type () 'unsigned-byte))

(defmacro get-time ()
  `(the time-type (get-internal-run-time)))

;;; NOTE: In Macintosh Common Lisp, CCL::GCTIME returns the number of
;;;       milliseconds spent during GC. We could subtract this from
;;;       the value returned by get-internal-run-time to eliminate
;;;       the effect of GC on the timing values, but we prefer to let
;;;       the user run without GC on. If the application is so big that
;;;       it requires GC to complete, then the GC times are part of the
;;;       cost of doing business, and will average out in the long run.
;;;       If it seems really important to a user that GC times not be
;;;       counted, then uncomment the following three lines and read-time
;;;       conditionalize the definition of get-time above with #-:openmcl.
;#+openmcl
;(defmacro get-time ()
;  `(the time-type (- (get-internal-run-time) (ccl:gctime))))

;;; ********************************
;;; Consing Functions **************
;;; ********************************
;;; The get-cons macro is called to find the total number of bytes
;;; consed since the beginning of time.

#+clisp
(defun get-cons ()
  (multiple-value-bind (real1 real2 run1 run2 gc1 gc2 space1 space2 gccount)
      (sys::%%time)
    (declare (ignore real1 real2 run1 run2 gc1 gc2 gccount))
    (dpb space1 (byte 24 24) space2)))

;;; Macintosh Common Lisp 2.0
;;; Note that this includes bytes that were allocated during GC.
;;; We could subtract this out by advising GC like we did under
;;; MCL 1.3.2, but I'd rather users ran without GC. If they can't
;;; run without GC, then the bytes consed during GC are a cost of
;;; running their program. Metering the code a few times will
;;; avoid the consing values being too lopsided. If a user really really
;;; wants to subtract out the consing during GC, replace the following
;;; two lines with the commented out code.
#+openmcl
(defmacro get-cons () `(the consing-type (ccl::total-bytes-allocated)))

#-(or clisp openmcl)
(progn
  (eval-when (compile eval)
    (warn "No consing will be reported unless a get-cons function is ~
           defined."))

  (defmacro get-cons () '(the consing-type 0)))

;; actually, neither `get-cons' nor `get-time' are used as is,
;; but only in the following macro `with-time/cons'
#-:clisp
(defmacro with-time/cons ((delta-time delta-cons) form &body post-process)
  (let ((start-cons (gensym "START-CONS-"))
        (start-time (gensym "START-TIME-")))
    `(let ((,start-time (get-time)) (,start-cons (get-cons)))
       (declare (type time-type ,start-time)
                (type consing-type ,start-cons))
       (multiple-value-prog1 ,form
         (let ((,delta-time (- (get-time) ,start-time))
               (,delta-cons (- (get-cons) ,start-cons)))
           ,@post-process)))))

#+clisp
(progn
  (defmacro delta4 (nv1 nv2 ov1 ov2 by)
    `(- (dpb (- ,nv1 ,ov1) (byte ,by ,by) ,nv2) ,ov2))

  (let ((del (find-symbol "DELTA4" "SYS")))
    (when del (setf (fdefinition 'delta4) (fdefinition del))))

  (if (< internal-time-units-per-second 1000000)
      ;; TIME_1: AMIGA, OS/2, UNIX_TIMES
      (defmacro delta4-time (new-time1 new-time2 old-time1 old-time2)
        `(delta4 ,new-time1 ,new-time2 ,old-time1 ,old-time2 16))
      ;; TIME_2: other UNIX, WIN32
      (defmacro delta4-time (new-time1 new-time2 old-time1 old-time2)
        `(+ (* (- ,new-time1 ,old-time1) internal-time-units-per-second)
            (- ,new-time2 ,old-time2))))

  (defmacro delta4-cons (new-cons1 new-cons2 old-cons1 old-cons2)
    `(delta4 ,new-cons1 ,new-cons2 ,old-cons1 ,old-cons2 24))

  ;; avoid consing: when the application conses a lot,
  ;; get-cons may return a bignum, so we really should not use it.
  (defmacro with-time/cons ((delta-time delta-cons) form &body post-process)
    (let ((beg-cons1 (gensym "BEG-CONS1-")) (end-cons1 (gensym "END-CONS1-"))
          (beg-cons2 (gensym "BEG-CONS2-")) (end-cons2 (gensym "END-CONS2-"))
          (beg-time1 (gensym "BEG-TIME1-")) (end-time1 (gensym "END-TIME1-"))
          (beg-time2 (gensym "BEG-TIME2-")) (end-time2 (gensym "END-TIME2-"))
          (re1 (gensym)) (re2 (gensym)) (gc1 (gensym)) (gc2 (gensym)))
      `(multiple-value-bind (,re1 ,re2 ,beg-time1 ,beg-time2
                                  ,gc1 ,gc2 ,beg-cons1 ,beg-cons2)
	   (sys::%%time)
         (declare (ignore ,re1 ,re2 ,gc1 ,gc2))
         (multiple-value-prog1 ,form
           (multiple-value-bind (,re1 ,re2 ,end-time1 ,end-time2
                                      ,gc1 ,gc2 ,end-cons1 ,end-cons2)
	       (sys::%%time)
             (declare (ignore ,re1 ,re2 ,gc1 ,gc2))
             (let ((,delta-time (delta4-time ,end-time1 ,end-time2
                                             ,beg-time1 ,beg-time2))
                   (,delta-cons (delta4-cons ,end-cons1 ,end-cons2
                                             ,beg-cons1 ,beg-cons2)))
               ,@post-process)))))))

;;; ********************************
;;; Required Arguments *************
;;; ********************************
;;;
;;; Required (Fixed) vs Optional Args
;;;
;;; To avoid unnecessary consing in the "encapsulation" code, we find out the
;;; number of required arguments, and use &rest to capture only non-required
;;; arguments.  The function Required-Arguments returns two values: the first
;;; is the number of required arguments, and the second is T iff there are any
;;; non-required arguments (e.g. &optional, &rest, &key).

;;; Lucid, Allegro, and Macintosh Common Lisp
#+openmcl
(defun required-arguments (name)
  (let* ((function (symbol-function name))
         (args (ccl:arglist function))
         (pos (position-if #'(lambda (x)
                               (and (symbolp x)
                                    (let ((name (symbol-name x)))
                                      (and (>= (length name) 1)
                                           (char= (schar name 0)
                                                  #\&)))))
                           args)))
    (if pos
        (values pos t)
        (values (length args) nil))))

#+clisp
(defun required-arguments (name)
  (multiple-value-bind (name req-num opt-num rest-p key-p keywords allow-p)
      (sys::function-signature name t)
    (if name ; no error
        (values req-num (or (/= 0 opt-num) rest-p key-p keywords allow-p))
        (values 0 t))))

#-(or clisp openmcl)
(progn
 (eval-when (compile eval)
   (warn
    "You may want to add an implementation-specific ~
Required-Arguments function."))
 (eval-when (load eval)
   (defun required-arguments (name)
     (declare (ignore name))
     (values 0 t))))

#|
;;;Examples
(defun square (x) (* x x))
(defun square2 (x &optional y) (* x x y))
(defun test (x y &optional (z 3)) 3)
(defun test2 (x y &optional (z 3) &rest fred) 3)

(required-arguments 'square) => 1 nil
(required-arguments 'square2) => 1 t
(required-arguments 'test) => 2 t
(required-arguments 'test2) => 2 t
|#


;;; ****************************************************************
;;; Main METERING Code *********************************************
;;; ****************************************************************

;;; ********************************
;;; Global Variables ***************
;;; ********************************
(defvar *MONITOR-TIME-OVERHEAD* nil
  "The amount of time an empty monitored function costs.")
(defvar *MONITOR-CONS-OVERHEAD* nil
  "The amount of cons an empty monitored function costs.")

(defvar *TOTAL-TIME* 0
  "Total amount of time monitored so far.")
(defvar *TOTAL-CONS* 0
  "Total amount of consing monitored so far.")
(defvar *TOTAL-CALLS* 0
  "Total number of calls monitored so far.")
(proclaim '(type time-type *total-time*))
(proclaim '(type consing-type *total-cons*))
(proclaim '(fixnum *total-calls*))

;;; ********************************
;;; Accessor Functions *************
;;; ********************************
;;; Perhaps the SYMBOLP should be FBOUNDP? I.e., what about variables
;;; containing closures.
(defmacro PLACE-FUNCTION (function-place)
  "Return the function found at FUNCTION-PLACE. Evals FUNCTION-PLACE
if it isn't a symbol, to allow monitoring of closures located in
variables/arrays/structures."
  ;; Note that (fboundp 'fdefinition) returns T even if fdefinition
  ;; is a macro, which is what we want.
  (if (fboundp 'fdefinition)
      `(if (fboundp ,function-place)
           (fdefinition ,function-place)
           (eval ,function-place))
      `(if (symbolp ,function-place)
           (symbol-function ,function-place)
           (eval ,function-place))))

(defsetf PLACE-FUNCTION (function-place) (function)
  "Set the function in FUNCTION-PLACE to FUNCTION."
  (if (fboundp 'fdefinition)
      ;; If we're conforming to CLtL2, use fdefinition here.
      `(if (fboundp ,function-place)
           (setf (fdefinition ,function-place) ,function)
           (eval '(setf ,function-place ',function)))
      `(if (symbolp ,function-place)
           (setf (symbol-function ,function-place) ,function)
           (eval '(setf ,function-place ',function)))))

#|
;;; before using fdefinition
(defun PLACE-FUNCTION (function-place)
  "Return the function found at FUNCTION-PLACE. Evals FUNCTION-PLACE
if it isn't a symbol, to allow monitoring of closures located in
variables/arrays/structures."
  (if (symbolp function-place)
      (symbol-function function-place)
      (eval function-place)))

(defsetf PLACE-FUNCTION (function-place) (function)
  "Set the function in FUNCTION-PLACE to FUNCTION."
  `(if (symbolp ,function-place)
       (setf (symbol-function ,function-place) ,function)
       (eval '(setf ,function-place ',function))))
|#

(defun PLACE-FBOUNDP (function-place)
  "Test to see if FUNCTION-PLACE is a function."
  ;; probably should be
  #|(or (and (symbolp function-place)(fboundp function-place))
      (functionp (place-function function-place)))|#
  (if (symbolp function-place)
      (fboundp function-place)
      (functionp (place-function function-place))))

(defun PLACE-MACROP (function-place)
  "Test to see if FUNCTION-PLACE is a macro."
  (when (symbolp function-place)
    (macro-function function-place)))

;;; ********************************
;;; Measurement Tables *************
;;; ********************************
(defvar *monitored-functions* nil
  "List of monitored symbols.")

;;; We associate a METERING-FUNCTIONS structure with each monitored function
;;; name or other closure. This holds the functions that we call to manipulate
;;; the closure which implements the encapsulation.
;;;
(defstruct metering-functions
  (name nil)
  (old-definition nil :type function)
  (new-definition nil :type function)
  (read-metering  nil :type function)
  (reset-metering nil :type function))

;;; In general using hash tables in time-critical programs is a bad idea,
;;; because when one has to grow the table and rehash everything, the
;;; timing becomes grossly inaccurate. In this case it is not an issue
;;; because all inserting of entries in the hash table occurs before the
;;; timing commences. The only circumstance in which this could be a
;;; problem is if the lisp rehashes on the next reference to the table,
;;; instead of when the entry which forces a rehash was inserted.
;;;
;;; Note that a similar kind of problem can occur with GC, which is why
;;; one should turn off GC when monitoring code.
;;;
(defvar *monitor* (make-hash-table :test #'equal)
  "Hash table in which METERING-FUNCTIONS structures are stored.")
(defun get-monitor-info (name)
  (gethash name *monitor*))
(defsetf get-monitor-info (name) (info)
  `(setf (gethash ,name *monitor*) ,info))

(defun MONITORED (function-place)
  "Test to see if a FUNCTION-PLACE is monitored."
  (and (place-fboundp function-place)   ; this line necessary?
       (get-monitor-info function-place)))

(defun reset-monitoring-info (name)
  "Reset the monitoring info for the specified function."
  (let ((finfo (get-monitor-info name)))
    (when finfo
      (funcall (metering-functions-reset-metering finfo)))))
(defun reset-all-monitoring ()
  "Reset monitoring info for all functions."
  (setq *total-time* 0
        *total-cons* 0
        *total-calls* 0)
  (dolist (symbol *monitored-functions*)
    (when (monitored symbol)
      (reset-monitoring-info symbol))))

(defun monitor-info-values (name &optional (nested :exclusive) warn)
  "Returns monitoring information values for the named function,
adjusted for overhead."
  (let ((finfo (get-monitor-info name)))
    (if finfo
        (multiple-value-bind (inclusive-time inclusive-cons
                                             exclusive-time exclusive-cons
                                             calls nested-calls)
            (funcall (metering-functions-read-metering finfo))
          (unless (or (null warn)
                      (eq (place-function name)
                          (metering-functions-new-definition finfo)))
            (warn "Funtion ~S has been redefined, so times may be inaccurate.~@
                   MONITOR it again to record calls to the new definition."
                  name))
          (case nested
            (:exclusive (values calls
                                nested-calls
                                (- exclusive-time
                                   (* calls *monitor-time-overhead*))
                                (- exclusive-cons
                                   (* calls *monitor-cons-overhead*))))
            ;; In :inclusive mode, subtract overhead for all the
            ;; called functions as well. Nested-calls includes the
            ;; calls of the function as well. [Necessary 'cause of
            ;; functions which call themselves recursively.]
            (:inclusive (values calls
                                nested-calls
                                (- inclusive-time
                                   (* nested-calls ;(+ calls)
                                      *monitor-time-overhead*))
                                (- inclusive-cons
                                   (* nested-calls ;(+ calls)
                                      *monitor-cons-overhead*))))))
        (values 0 0 0 0))))

;;; ********************************
;;; Encapsulate ********************
;;; ********************************
(eval-when (compile load eval)
;; Returns a lambda expression for a function that, when called with the
;; function name, will set up that function for metering.
;;
;; A function is monitored by replacing its definition with a closure
;; created by the following function. The closure records the monitoring
;; data, and updates the data with each call of the function.
;;
;; Other closures are used to read and reset the data.
(defun make-monitoring-encapsulation (min-args optionals-p)
  (let (required-args)
    (dotimes (i min-args) (push (gensym) required-args))
    `(lambda (name)
       (let ((inclusive-time 0)
	     (inclusive-cons 0)
	     (exclusive-time 0)
	     (exclusive-cons 0)
	     (calls 0)
	     (nested-calls 0)
	     (old-definition (place-function name)))
	 (declare (type time-type inclusive-time)
		  (type time-type exclusive-time)
		  (type consing-type inclusive-cons)
		  (type consing-type exclusive-cons)
		  (fixnum calls)
		  (fixnum nested-calls))
	 (pushnew name *monitored-functions*)

	 (setf (place-function name)
	       #'(lambda (,@required-args
			  ,@(when optionals-p
                              `(&rest optional-args)))
		   (let ((prev-total-time *total-time*)
			 (prev-total-cons *total-cons*)
			 (prev-total-calls *total-calls*)
			 ;; (old-time inclusive-time)
			 ;; (old-cons inclusive-cons)
			 ;; (old-nested-calls nested-calls)
			 )
		     (declare (type time-type prev-total-time)
			      (type consing-type prev-total-cons)
			      (fixnum prev-total-calls))
                     (with-time/cons (delta-time delta-cons)
                       ;; form
                       ,(if optionals-p
                            `(apply old-definition
                                    ,@required-args optional-args)
                            `(funcall old-definition ,@required-args))
                       ;; post-processing:
                       ;; Calls
                       (incf calls)
                       (incf *total-calls*)
                       ;; nested-calls includes this call
                       (incf nested-calls (the fixnum
                                            (- *total-calls*
                                               prev-total-calls)))
                       ;; (setf nested-calls (+ old-nested-calls
                       ;;                       (- *total-calls*
                       ;;                          prev-total-calls)))
                       ;; Time
                       ;; Problem with inclusive time is that it
                       ;; currently doesn't add values from recursive
                       ;; calls to the same function. Change the
                       ;; setf to an incf to fix this?
                       (incf inclusive-time (the time-type delta-time))
                       ;; (setf inclusive-time (+ delta-time old-time))
                       (incf exclusive-time (the time-type
                                              (+ delta-time
                                                 (- prev-total-time
                                                    *total-time*))))
                       (setf *total-time* (the time-type
                                            (+ delta-time
                                               prev-total-time)))
                       ;; Consing
                       (incf inclusive-cons (the consing-type delta-cons))
                       ;; (setf inclusive-cons (+ delta-cons old-cons))
                       (incf exclusive-cons (the consing-type
                                              (+ delta-cons
                                                 (- prev-total-cons
                                                    *total-cons*))))
                       (setf *total-cons*
                             (the consing-type
                               (+ delta-cons prev-total-cons)))))))
	 (setf (get-monitor-info name)
	       (make-metering-functions
		:name name
		:old-definition old-definition
		:new-definition (place-function name)
		:read-metering #'(lambda ()
				   (values inclusive-time
					   inclusive-cons
					   exclusive-time
					   exclusive-cons
					   calls
					   nested-calls))
		:reset-metering #'(lambda ()
				    (setq inclusive-time 0
					  inclusive-cons 0
					  exclusive-time 0
					  exclusive-cons 0
					  calls 0
					  nested-calls 0)
				    t)))))))
);; End of EVAL-WHEN

;;; For efficiency reasons, we precompute the encapsulation functions
;;; for a variety of combinations of argument structures
;;; (min-args . optional-p). These are stored in the following hash table
;;; along with any new ones we encounter. Since we're now precomputing
;;; closure functions for common argument signatures, this eliminates
;;; the former need to call COMPILE for each monitored function.
(eval-when (compile eval)
   (defconstant precomputed-encapsulations 8))

(defvar *existing-encapsulations* (make-hash-table :test #'equal))
(defun find-encapsulation (min-args optionals-p)
  (or (gethash (cons min-args optionals-p) *existing-encapsulations*)
      (setf (gethash (cons min-args optionals-p) *existing-encapsulations*)
            (compile nil
                     (make-monitoring-encapsulation min-args optionals-p)))))

(macrolet ((frob ()
             (let ((res ()))
               (dotimes (i precomputed-encapsulations)
                 (push `(setf (gethash '(,i . nil) *existing-encapsulations*)
                              #',(make-monitoring-encapsulation i nil))
                       res)
                 (push `(setf (gethash '(,i . t) *existing-encapsulations*)
                              #',(make-monitoring-encapsulation i t))
                       res))
               `(progn ,@res))))
  (frob))

(defun monitoring-encapsulate (name &optional warn)
  "Monitor the function Name. If already monitored, unmonitor first."
  ;; Saves the current definition of name and inserts a new function which
  ;; returns the result of evaluating body.
  (cond ((not (place-fboundp name))     ; not a function
         (when warn
           (warn "Ignoring undefined function ~S." name)))
        ((place-macrop name)            ; a macro
         (when warn
           (warn "Ignoring macro ~S." name)))
        (t                              ; tis a function
         (when (get-monitor-info name) ; monitored
           (when warn
             (warn "~S already monitored, so unmonitoring it first." name))
           (monitoring-unencapsulate name))
         (multiple-value-bind (min-args optionals-p)
             (required-arguments name)
           (funcall (find-encapsulation min-args optionals-p) name)))))

(defun monitoring-unencapsulate (name &optional warn)
  "Removes monitoring encapsulation code from around Name."
  (let ((finfo (get-monitor-info name)))
    (when finfo                         ; monitored
      (remprop name 'metering-functions)
      (setq *monitored-functions*
            (remove name *monitored-functions* :test #'equal))
      (if (eq (place-function name)
              (metering-functions-new-definition finfo))
          (setf (place-function name)
                (metering-functions-old-definition finfo))
          (when warn
            (warn "Preserving current definition of redefined function ~S."
                  name))))))

;;; ********************************
;;; Main Monitoring Functions ******
;;; ********************************
(defmacro MONITOR (&rest names)
  "Monitor the named functions. As in TRACE, the names are not evaluated.
   If a function is already monitored, then unmonitor and remonitor (useful
   to notice function redefinition). If a name is undefined, give a warning
   and ignore it. See also unmonitor, report-monitoring,
   display-monitoring-results and reset-time."
  `(progn
     ,@(mapcar #'(lambda (name) `(monitoring-encapsulate ',name)) names)
     *monitored-functions*))

(defmacro UNMONITOR (&rest names)
  "Remove the monitoring on the named functions.
   Names defaults to the list of all currently monitored functions."
  `(dolist (name ,(if names `',names '*monitored-functions*) (values))
     (monitoring-unencapsulate name)))

(defun MONITOR-ALL (&optional (package *package*))
  "Monitor all functions in the specified package."
  (let ((package (if (packagep package)
		     package
		     (find-package package))))
    (do-symbols (symbol package)
      (when (eq (symbol-package symbol) package)
        (monitoring-encapsulate symbol)))))

(defmacro MONITOR-FORM (form
                        &optional (nested :exclusive) (threshold 0.01)
                        (key :percent-time))
  "Monitor the execution of all functions in the current package
during the execution of FORM.  All functions that are executed above
THRESHOLD % will be reported."
  `(unwind-protect
       (progn
         (monitor-all)
         (reset-all-monitoring)
         (prog1
             (time ,form)
           (report-monitoring :all ,nested ,threshold ,key :ignore-no-calls)))
     (unmonitor)))

(defmacro WITH-MONITORING ((&rest functions)
                           (&optional (nested :exclusive)
                                      (threshold 0.01)
                                      (key :percent-time))
                           &body body)
  "Monitor the specified functions during the execution of the body."
  `(unwind-protect
       (progn
         (dolist (fun ',functions)
           (monitoring-encapsulate fun))
         (reset-all-monitoring)
         ,@body
         (report-monitoring :all ,nested ,threshold ,key))
     (unmonitor)))

;;; ********************************
;;; Overhead Calculations **********
;;; ********************************
(defconstant overhead-iterations 5000
  "Number of iterations over which the timing overhead is averaged.")

;;; Perhaps this should return something to frustrate clever compilers.
(defun STUB-FUNCTION (x)
  (declare (ignore x))
  nil)
(proclaim '(notinline stub-function))

(defun SET-MONITOR-OVERHEAD ()
  "Determines the average overhead of monitoring by monitoring the execution
of an empty function many times."
  (setq *monitor-time-overhead* 0
        *monitor-cons-overhead* 0)
  (stub-function nil)
  (monitor stub-function)
  (reset-all-monitoring)
  (let ((overhead-function (symbol-function 'stub-function)))
    (dotimes (x overhead-iterations)
      (funcall overhead-function overhead-function)))
;  (dotimes (x overhead-iterations)
;    (stub-function nil))
  (let ((fiter (float overhead-iterations)))
    (multiple-value-bind (calls nested-calls time cons)
        (monitor-info-values 'stub-function)
      (declare (ignore calls nested-calls))
      (setq *monitor-time-overhead* (/ time fiter)
            *monitor-cons-overhead* (/ cons fiter))))
  (unmonitor stub-function))
(set-monitor-overhead)

;;; ********************************
;;; Report Data ********************
;;; ********************************
(defvar *monitor-results* nil
  "A table of monitoring statistics is stored here.")
(defvar *no-calls* nil
  "A list of monitored functions which weren't called.")
(defvar *estimated-total-overhead* 0)
;; (proclaim '(type time-type *estimated-total-overhead*))

(defstruct (monitoring-info
            (:conc-name m-info-)
            (:constructor make-monitoring-info
                          (name calls time cons
                                percent-time percent-cons
                                time-per-call cons-per-call)))
  name
  calls
  time
  cons
  percent-time
  percent-cons
  time-per-call
  cons-per-call)

(defun REPORT (&key (names :all)
		    (nested :exclusive)
		    (threshold 0.01)
		    (sort-key :percent-time)
		    (ignore-no-calls nil))
  "Same as REPORT-MONITORING but with a nicer keyword interface"
  (declare (type (member :function :percent-time :time :percent-cons
			 :cons :calls :time-per-call :cons-per-call)
		 sort-key)
	   (type (member :inclusive :exclusive) nested))
  (report-monitoring names nested threshold sort-key ignore-no-calls))

(defun REPORT-MONITORING (&optional names
				    (nested :exclusive)
				    (threshold 0.01)
				    (key :percent-time)
				    ignore-no-calls)
  "Report the current monitoring state.
The percentage of the total time spent executing unmonitored code
in each function (:exclusive mode), or total time (:inclusive mode)
will be printed together with the number of calls and
the unmonitored time per call.  Functions that have been executed
below THRESHOLD % of the time will not be reported.  To report on all
functions set NAMES to be either NIL or :ALL."
  (when (or (null names) (eq names :all)) (setq names *monitored-functions*))

  (let ((total-time 0)
        (total-cons 0)
        (total-calls 0))
    ;; Compute overall time and consing.
    (dolist (name names)
      (multiple-value-bind (calls nested-calls time cons)
          (monitor-info-values name nested :warn)
        (declare (ignore nested-calls))
        (incf total-calls calls)
        (incf total-time time)
        (incf total-cons cons)))
    ;; Total overhead.
    (setq *estimated-total-overhead*
          (/ (* *monitor-time-overhead* total-calls)
             time-units-per-second))
    ;; Assemble data for only the specified names (all monitored functions)
    (if (zerop total-time)
        (format *trace-output* "Not enough execution time to monitor.")
        (progn
          (setq *monitor-results* nil *no-calls* nil)
          (dolist (name names)
            (multiple-value-bind (calls nested-calls time cons)
                (monitor-info-values name nested)
              (declare (ignore nested-calls))
              (when (minusp time) (setq time 0.0))
              (when (minusp cons) (setq cons 0.0))
              (if (zerop calls)
                  (push (if (symbolp name)
                            (symbol-name name)
                            (format nil "~S" name))
                        *no-calls*)
                  (push (make-monitoring-info
                         (format nil "~S" name) ; name
                         calls          ; calls
                         (/ time (float time-units-per-second)) ; time in secs
                         (round cons)   ; consing
                         (/ time (float total-time)) ; percent-time
                         (if (zerop total-cons) 0
                             (/ cons (float total-cons))) ; percent-cons
                         (/ (/ time (float calls)) ; time-per-call
                            time-units-per-second) ; sec/call
                         (round (/ cons (float calls)))) ; cons-per-call
                        *monitor-results*))))
          (display-monitoring-results threshold key ignore-no-calls)))))

(defun display-monitoring-results (&optional (threshold 0.01)
				     (key :percent-time)
				     (ignore-no-calls t))
  (let ((max-length 8)			; Function header size
	(max-cons-length 8)
	(total-time 0.0)
	(total-consed 0)
	(total-calls 0)
	(total-percent-time 0)
	(total-percent-cons 0))
    (sort-results key)
    (dolist (result *monitor-results*)
      (when (or (zerop threshold)
		(> (m-info-percent-time result) threshold))
	(setq max-length
	      (max max-length
		   (length (m-info-name result))))
	(setq max-cons-length
	      (max max-cons-length
		   (m-info-cons-per-call result)))))
    (incf max-length 2)
    (setf max-cons-length (+ 2 (ceiling (log max-cons-length 10))))
    (format *trace-output*
	    "~%~%~
                       ~VT                                     ~VA~
	     ~%        ~VT   %      %                          ~VA  ~
Total     Total~
	     ~%Function~VT  Time   Cons    Calls  Sec/Call     ~VA  ~
Time      Cons~
             ~%~V,,,'-A"
	    max-length
	    max-cons-length "Cons"
	    max-length
	    max-cons-length "Per"
	    max-length
	    max-cons-length "Call"
	    (+ max-length 62 (max 0 (- max-cons-length 5))) "-")
    (dolist (result *monitor-results*)
      (when (or (zerop threshold)
		(> (m-info-percent-time result) threshold))
	(format *trace-output*
		"~%~A:~VT~6,2F  ~6,2F  ~7D  ~,6F  ~VD  ~8,3F  ~10D"
		(m-info-name result)
		max-length
		(* 100 (m-info-percent-time result))
		(* 100 (m-info-percent-cons result))
		(m-info-calls result)
		(m-info-time-per-call result)
		max-cons-length
		(m-info-cons-per-call result)
		(m-info-time result)
		(m-info-cons result))
	(incf total-time (m-info-time result))
	(incf total-consed (m-info-cons result))
	(incf total-calls (m-info-calls result))
	(incf total-percent-time (m-info-percent-time result))
	(incf total-percent-cons (m-info-percent-cons result))))
    (format *trace-output*
	    "~%~V,,,'-A~
	    ~%TOTAL:~VT~6,2F  ~6,2F  ~7D  ~9@T ~VA  ~8,3F  ~10D~
            ~%Estimated monitoring overhead: ~5,2F seconds~
            ~%Estimated total monitoring overhead: ~5,2F seconds"
	    (+ max-length 62 (max 0 (- max-cons-length 5))) "-"
	    max-length
	    (* 100 total-percent-time)
	    (* 100 total-percent-cons)
	    total-calls
	    max-cons-length " "
	    total-time total-consed
	    (/ (* *monitor-time-overhead* total-calls)
	       time-units-per-second)
	    *estimated-total-overhead*)
    (when (and (not ignore-no-calls) *no-calls*)
      (setq *no-calls* (sort *no-calls* #'string<))
      (let ((num-no-calls (length *no-calls*)))
        (if (> num-no-calls 20)
            (format *trace-output*
                    "~%~@(~r~) monitored functions were not called. ~
                      ~%See the variable mon::*no-calls* for a list."
                    num-no-calls)
            (format *trace-output*
                    "~%The following monitored functions were not called:~
                ~%~{~<~%~:; ~A~>~}~%"
                    *no-calls*))))
    (values)))

(defun sort-results (&optional (key :percent-time))
  (setq *monitor-results*
        (case key
          (:function             (sort *monitor-results* #'string>
                                       :key #'m-info-name))
          ((:percent-time :time) (sort *monitor-results* #'>
                                       :key #'m-info-time))
          ((:percent-cons :cons) (sort *monitor-results* #'>
                                       :key #'m-info-cons))
          (:calls                (sort *monitor-results* #'>
                                       :key #'m-info-calls))
          (:time-per-call        (sort *monitor-results* #'>
                                       :key #'m-info-time-per-call))
          (:cons-per-call        (sort *monitor-results* #'>
                                       :key #'m-info-cons-per-call)))))

;;; *END OF FILE*


