This file is indexed.

/usr/share/guile/2.0/statprof.scm is in guile-2.0-libs 2.0.9+1-1ubuntu1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
;;;; (statprof) -- a statistical profiler for Guile
;;;; -*-scheme-*-
;;;;
;;;; 	Copyright (C) 2009, 2010, 2011  Free Software Foundation, Inc.
;;;;    Copyright (C) 2004, 2009 Andy Wingo <wingo at pobox dot com>
;;;;    Copyright (C) 2001 Rob Browning <rlb at defaultvalue dot org>
;;;; 
;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;; 
;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;;; Lesser General Public License for more details.
;;;; 
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
;;;; 


;;; Commentary:
;;
;;@code{(statprof)} is intended to be a fairly simple
;;statistical profiler for guile. It is in the early stages yet, so
;;consider its output still suspect, and please report any bugs to
;;@email{guile-devel at gnu.org}, or to me directly at @email{rlb at
;;defaultvalue.org}.
;;
;;A simple use of statprof would look like this:
;;
;;@example
;;  (statprof-reset 0 50000 #t)
;;  (statprof-start)
;;  (do-something)
;;  (statprof-stop)
;;  (statprof-display)
;;@end example
;;
;;This would reset statprof, clearing all accumulated statistics, then
;;start profiling, run some code, stop profiling, and finally display a
;;gprof flat-style table of statistics which will look something like
;;this:
;;
;;@example
;;  %   cumulative      self              self    total
;; time    seconds   seconds    calls  ms/call  ms/call  name
;; 35.29      0.23      0.23     2002     0.11     0.11  -
;; 23.53      0.15      0.15     2001     0.08     0.08  positive?
;; 23.53      0.15      0.15     2000     0.08     0.08  +
;; 11.76      0.23      0.08     2000     0.04     0.11  do-nothing
;;  5.88      0.64      0.04     2001     0.02     0.32  loop
;;  0.00      0.15      0.00        1     0.00   150.59  do-something
;; ...
;;@end example
;;
;;All of the numerical data with the exception of the calls column is
;;statistically approximate. In the following column descriptions, and
;;in all of statprof, "time" refers to execution time (both user and
;;system), not wall clock time.
;;
;;@table @asis
;;@item % time
;;The percent of the time spent inside the procedure itself
;;(not counting children).
;;@item cumulative seconds
;;The total number of seconds spent in the procedure, including
;;children.
;;@item self seconds
;;The total number of seconds spent in the procedure itself (not counting
;;children).
;;@item calls
;;The total number of times the procedure was called.
;;@item self ms/call
;;The average time taken by the procedure itself on each call, in ms.
;;@item total ms/call
;;The average time taken by each call to the procedure, including time
;;spent in child functions.
;;@item name
;;The name of the procedure.
;;@end table
;;
;;The profiler uses @code{eq?} and the procedure object itself to
;;identify the procedures, so it won't confuse different procedures with
;;the same name. They will show up as two different rows in the output.
;;
;;Right now the profiler is quite simplistic.  I cannot provide
;;call-graphs or other higher level information.  What you see in the
;;table is pretty much all there is. Patches are welcome :-)
;;
;;@section Implementation notes
;;
;;The profiler works by setting the unix profiling signal
;;@code{ITIMER_PROF} to go off after the interval you define in the call
;;to @code{statprof-reset}. When the signal fires, a sampling routine is
;;run which looks at the current procedure that's executing, and then
;;crawls up the stack, and for each procedure encountered, increments
;;that procedure's sample count. Note that if a procedure is encountered
;;multiple times on a given stack, it is only counted once. After the
;;sampling is complete, the profiler resets profiling timer to fire
;;again after the appropriate interval.
;;
;;Meanwhile, the profiler keeps track, via @code{get-internal-run-time},
;;how much CPU time (system and user -- which is also what
;;@code{ITIMER_PROF} tracks), has elapsed while code has been executing
;;within a statprof-start/stop block.
;;
;;The profiler also tries to avoid counting or timing its own code as
;;much as possible.
;;
;;; Code:

;; When you add new features, please also add tests to ./tests/ if you
;; have time, and then add the new files to ./run-tests.  Also, if
;; anyone's bored, there are a lot of existing API bits that don't
;; have tests yet.

;; TODO
;;
;; Check about profiling C functions -- does profiling primitives work?
;; Also look into stealing code from qprof so we can sample the C stack
;; Call graphs?

(define-module (statprof)
  #:use-module (srfi srfi-1)
  #:autoload   (ice-9 format) (format)
  #:use-module (system vm vm)
  #:use-module (system vm frame)
  #:use-module (system vm program)
  #:export (statprof-active?
            statprof-start
            statprof-stop
            statprof-reset

            statprof-accumulated-time
            statprof-sample-count
            statprof-fold-call-data
            statprof-proc-call-data
            statprof-call-data-name
            statprof-call-data-calls
            statprof-call-data-cum-samples
            statprof-call-data-self-samples
            statprof-call-data->stats
           
            statprof-stats-proc-name
            statprof-stats-%-time-in-proc
            statprof-stats-cum-secs-in-proc
            statprof-stats-self-secs-in-proc
            statprof-stats-calls
            statprof-stats-self-secs-per-call
            statprof-stats-cum-secs-per-call

            statprof-display
            statprof-display-anomolies

            statprof-fetch-stacks
            statprof-fetch-call-tree

            statprof
            with-statprof

            gcprof))


;; This profiler tracks two numbers for every function called while
;; it's active.  It tracks the total number of calls, and the number
;; of times the function was active when the sampler fired.
;;
;; Globally the profiler tracks the total time elapsed and the number
;; of times the sampler was fired.
;;
;; Right now, this profiler is not per-thread and is not thread safe.

(define accumulated-time #f)            ; total so far.
(define last-start-time #f)             ; start-time when timer is active.
(define sample-count #f)                ; total count of sampler calls.
(define sampling-frequency #f)          ; in (seconds . microseconds)
(define remaining-prof-time #f)         ; time remaining when prof suspended.
(define profile-level 0)                ; for user start/stop nesting.
(define %count-calls? #t)               ; whether to catch apply-frame.
(define gc-time-taken 0)                ; gc time between statprof-start and
                                        ; statprof-stop.
(define record-full-stacks? #f)         ; if #t, stash away the stacks
                                        ; for later analysis.
(define stacks '())

;; procedure-data will be a hash where the key is the function object
;; itself and the value is the data. The data will be a vector like
;; this: #(name call-count cum-sample-count self-sample-count)
(define procedure-data #f)

;; If you change the call-data data structure, you need to also change
;; sample-uncount-frame.
(define (make-call-data proc call-count cum-sample-count self-sample-count)
  (vector proc call-count cum-sample-count self-sample-count))
(define (call-data-proc cd) (vector-ref cd 0))
(define (call-data-name cd) (procedure-name (call-data-proc cd)))
(define (call-data-printable cd)
  (or (call-data-name cd)
      (with-output-to-string (lambda () (write (call-data-proc cd))))))
(define (call-data-call-count cd) (vector-ref cd 1))
(define (call-data-cum-sample-count cd) (vector-ref cd 2))
(define (call-data-self-sample-count cd) (vector-ref cd 3))

(define (inc-call-data-call-count! cd)
  (vector-set! cd 1 (1+ (vector-ref cd 1))))
(define (inc-call-data-cum-sample-count! cd)
  (vector-set! cd 2 (1+ (vector-ref cd 2))))
(define (inc-call-data-self-sample-count! cd)
  (vector-set! cd 3 (1+ (vector-ref cd 3))))

(define-macro (accumulate-time stop-time)
  `(set! accumulated-time
         (+ accumulated-time 0.0 (- ,stop-time last-start-time))))

(define (get-call-data proc)
  (let ((k (if (or (not (program? proc))
                   (zero? (program-num-free-variables proc)))
               proc
               (program-objcode proc))))
    (or (hashq-ref procedure-data k)
        (let ((call-data (make-call-data proc 0 0 0)))
          (hashq-set! procedure-data k call-data)
          call-data))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; SIGPROF handler

(define (sample-stack-procs stack)
  (let ((stacklen (stack-length stack))
        (hit-count-call? #f))

    (if record-full-stacks?
        (set! stacks (cons stack stacks)))

    (set! sample-count (+ sample-count 1))
    ;; Now accumulate stats for the whole stack.
    (let loop ((frame (stack-ref stack 0))
               (procs-seen (make-hash-table 13))
               (self #f))
      (cond
       ((not frame)
        (hash-fold
         (lambda (proc val accum)
           (inc-call-data-cum-sample-count!
            (get-call-data proc)))
         #f
         procs-seen)
        (and=> (and=> self get-call-data)
               inc-call-data-self-sample-count!))
       ((frame-procedure frame)
        => (lambda (proc)
             (cond
              ((eq? proc count-call)
               ;; We're not supposed to be sampling count-call and
               ;; its sub-functions, so loop again with a clean
               ;; slate.
               (set! hit-count-call? #t)
               (loop (frame-previous frame) (make-hash-table 13) #f))
              (else
               (hashq-set! procs-seen proc #t)
               (loop (frame-previous frame)
                     procs-seen
                     (or self proc))))))
       (else
        (loop (frame-previous frame) procs-seen self))))
    hit-count-call?))

(define inside-profiler? #f)

(define (profile-signal-handler sig)
  (set! inside-profiler? #t)

  ;; FIXME: with-statprof should be able to set an outer frame for the
  ;; stack cut
  (if (positive? profile-level)
      (let* ((stop-time (get-internal-run-time))
             ;; cut down to the signal handler. note that this will only
             ;; work if statprof.scm is compiled; otherwise we get
             ;; `eval' on the stack instead, because if it's not
             ;; compiled, profile-signal-handler is a thunk that
             ;; tail-calls eval. perhaps we should always compile the
             ;; signal handler instead...
             (stack (or (make-stack #t profile-signal-handler)
                        (pk 'what! (make-stack #t))))
             (inside-apply-trap? (sample-stack-procs stack)))

        (if (not inside-apply-trap?)
            (begin
              ;; disabling here is just a little more efficient, but
              ;; not necessary given inside-profiler?.  We can't just
              ;; disable unconditionally at the top of this function
              ;; and eliminate inside-profiler? because it seems to
              ;; confuse guile wrt re-enabling the trap when
              ;; count-call finishes.
              (if %count-calls?
                  (set-vm-trace-level! (the-vm)
                                       (1- (vm-trace-level (the-vm)))))
              (accumulate-time stop-time)))
        
        (setitimer ITIMER_PROF
                   0 0
                   (car sampling-frequency)
                   (cdr sampling-frequency))
        
        (if (not inside-apply-trap?)
            (begin
              (set! last-start-time (get-internal-run-time))
              (if %count-calls?
                  (set-vm-trace-level! (the-vm)
                                       (1+ (vm-trace-level (the-vm)))))))))
  
  (set! inside-profiler? #f))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Count total calls.

(define (count-call frame)
  (if (not inside-profiler?)
      (begin
        (accumulate-time (get-internal-run-time))

        (and=> (frame-procedure frame)
               (lambda (proc)
                 (inc-call-data-call-count!
                  (get-call-data proc))))
        
        (set! last-start-time (get-internal-run-time)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (statprof-active?)
  "Returns @code{#t} if @code{statprof-start} has been called more times
than @code{statprof-stop}, @code{#f} otherwise."
  (positive? profile-level))

;; Do not call this from statprof internal functions -- user only.
(define (statprof-start)
  "Start the profiler.@code{}"
  ;; After some head-scratching, I don't *think* I need to mask/unmask
  ;; signals here, but if I'm wrong, please let me know.
  (set! profile-level (+ profile-level 1))
  (if (= profile-level 1)
      (let* ((rpt remaining-prof-time)
             (use-rpt? (and rpt
                            (or (positive? (car rpt))
                                (positive? (cdr rpt))))))
        (set! remaining-prof-time #f)
        (set! last-start-time (get-internal-run-time))
        (set! gc-time-taken
              (cdr (assq 'gc-time-taken (gc-stats))))
        (if use-rpt?
            (setitimer ITIMER_PROF 0 0 (car rpt) (cdr rpt))
            (setitimer ITIMER_PROF
                       0 0
                       (car sampling-frequency)
                       (cdr sampling-frequency)))
        (if %count-calls?
            (add-hook! (vm-apply-hook (the-vm)) count-call))
        (set-vm-trace-level! (the-vm) (1+ (vm-trace-level (the-vm))))
        #t)))
  
;; Do not call this from statprof internal functions -- user only.
(define (statprof-stop)
  "Stop the profiler.@code{}"
  ;; After some head-scratching, I don't *think* I need to mask/unmask
  ;; signals here, but if I'm wrong, please let me know.
  (set! profile-level (- profile-level 1))
  (if (zero? profile-level)
      (begin
        (set! gc-time-taken
              (- (cdr (assq 'gc-time-taken (gc-stats))) gc-time-taken))
        (set-vm-trace-level! (the-vm) (1- (vm-trace-level (the-vm))))
        (if %count-calls?
            (remove-hook! (vm-apply-hook (the-vm)) count-call))
        ;; I believe that we need to do this before getting the time
        ;; (unless we want to make things even more complicated).
        (set! remaining-prof-time (setitimer ITIMER_PROF 0 0 0 0))
        (accumulate-time (get-internal-run-time))
        (set! last-start-time #f))))

(define* (statprof-reset sample-seconds sample-microseconds count-calls?
                         #:optional full-stacks?)
  "Reset the statprof sampler interval to @var{sample-seconds} and
@var{sample-microseconds}. If @var{count-calls?} is true, arrange to
instrument procedure calls as well as collecting statistical profiling
data. If @var{full-stacks?} is true, collect all sampled stacks into a
list for later analysis.

Enables traps and debugging as necessary."
  (if (positive? profile-level)
      (error "Can't reset profiler while profiler is running."))
  (set! %count-calls? count-calls?)
  (set! accumulated-time 0)
  (set! last-start-time #f)
  (set! sample-count 0)
  (set! sampling-frequency (cons sample-seconds sample-microseconds))
  (set! remaining-prof-time #f)
  (set! procedure-data (make-hash-table 131))
  (set! record-full-stacks? full-stacks?)
  (set! stacks '())
  (sigaction SIGPROF profile-signal-handler)
  #t)

(define (statprof-fold-call-data proc init)
  "Fold @var{proc} over the call-data accumulated by statprof. Cannot be
called while statprof is active. @var{proc} should take two arguments,
@code{(@var{call-data} @var{prior-result})}.

Note that a given proc-name may appear multiple times, but if it does,
it represents different functions with the same name."
  (if (positive? profile-level)
      (error "Can't call statprof-fold-called while profiler is running."))

  (hash-fold
   (lambda (key value prior-result)
     (proc value prior-result))
   init
   procedure-data))

(define (statprof-proc-call-data proc)
  "Returns the call-data associated with @var{proc}, or @code{#f} if
none is available."
  (if (positive? profile-level)
      (error "Can't call statprof-fold-called while profiler is running."))

  (hashq-ref procedure-data proc))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Stats

(define (statprof-call-data->stats call-data)
  "Returns an object of type @code{statprof-stats}."
  ;; returns (vector proc-name
  ;;                 %-time-in-proc
  ;;                 cum-seconds-in-proc
  ;;                 self-seconds-in-proc
  ;;                 num-calls
  ;;                 self-secs-per-call
  ;;                 total-secs-per-call)

  (let* ((proc-name (call-data-printable call-data))
         (self-samples (call-data-self-sample-count call-data))
         (cum-samples (call-data-cum-sample-count call-data))
         (all-samples (statprof-sample-count))
         (secs-per-sample (/ (statprof-accumulated-time)
                             (statprof-sample-count)))
         (num-calls (and %count-calls? (statprof-call-data-calls call-data))))

    (vector proc-name
            (* (/ self-samples all-samples) 100.0)
            (* cum-samples secs-per-sample 1.0)
            (* self-samples secs-per-sample 1.0)
            num-calls
            (and num-calls ;; maybe we only sampled in children
                 (if (zero? self-samples) 0.0
                     (/ (* self-samples secs-per-sample) 1.0 num-calls)))
            (and num-calls ;; cum-samples must be positive
                 (/ (* cum-samples secs-per-sample)
                    1.0
                    ;; num-calls might be 0 if we entered statprof during the
                    ;; dynamic extent of the call
                    (max num-calls 1))))))

(define (statprof-stats-proc-name stats) (vector-ref stats 0))
(define (statprof-stats-%-time-in-proc stats) (vector-ref stats 1))
(define (statprof-stats-cum-secs-in-proc stats) (vector-ref stats 2))
(define (statprof-stats-self-secs-in-proc stats) (vector-ref stats 3))
(define (statprof-stats-calls stats) (vector-ref stats 4))
(define (statprof-stats-self-secs-per-call stats) (vector-ref stats 5))
(define (statprof-stats-cum-secs-per-call stats) (vector-ref stats 6))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (stats-sorter x y)
  (let ((diff (- (statprof-stats-self-secs-in-proc x)
                 (statprof-stats-self-secs-in-proc y))))
    (positive?
     (if (= diff 0)
         (- (statprof-stats-cum-secs-in-proc x)
            (statprof-stats-cum-secs-in-proc y))
         diff))))

(define (statprof-display . port)
  "Displays a gprof-like summary of the statistics collected. Unless an
optional @var{port} argument is passed, uses the current output port."
  (if (null? port) (set! port (current-output-port)))
  
  (cond
   ((zero? (statprof-sample-count))
    (format port "No samples recorded.\n"))
   (else
    (let* ((stats-list (statprof-fold-call-data
                        (lambda (data prior-value)
                          (cons (statprof-call-data->stats data)
                                prior-value))
                        '()))
           (sorted-stats (sort stats-list stats-sorter)))

      (define (display-stats-line stats)
        (if %count-calls?
            (format  port "~6,2f ~9,2f ~9,2f ~7d ~8,2f ~8,2f  "
                     (statprof-stats-%-time-in-proc stats)
                     (statprof-stats-cum-secs-in-proc stats)
                     (statprof-stats-self-secs-in-proc stats)
                     (statprof-stats-calls stats)
                     (* 1000 (statprof-stats-self-secs-per-call stats))
                     (* 1000 (statprof-stats-cum-secs-per-call stats)))
            (format  port "~6,2f ~9,2f ~9,2f  "
                     (statprof-stats-%-time-in-proc stats)
                     (statprof-stats-cum-secs-in-proc stats)
                     (statprof-stats-self-secs-in-proc stats)))
        (display (statprof-stats-proc-name stats) port)
        (newline port))
    
      (if %count-calls?
          (begin
            (format  port "~5a ~10a   ~7a ~8a ~8a ~8a  ~8@a\n"
                     "%  " "cumulative" "self" "" "self" "total" "")
            (format  port "~5a  ~9a  ~8a ~8a ~8a ~8a  ~8@a\n"
                     "time" "seconds" "seconds" "calls" "ms/call" "ms/call" "name"))
          (begin
            (format  port "~5a ~10a   ~7a  ~8@a\n"
                     "%" "cumulative" "self" "")
            (format  port "~5a  ~10a  ~7a  ~8@a\n"
                     "time" "seconds" "seconds" "name")))

      (for-each display-stats-line sorted-stats)

      (display "---\n" port)
      (simple-format #t "Sample count: ~A\n" (statprof-sample-count))
      (simple-format #t "Total time: ~A seconds (~A seconds in GC)\n"
                     (statprof-accumulated-time)
                     (/ gc-time-taken 1.0 internal-time-units-per-second))))))

(define (statprof-display-anomolies)
  "A sanity check that attempts to detect anomolies in statprof's
statistics.@code{}"
  (statprof-fold-call-data
   (lambda (data prior-value)
     (if (and %count-calls?
              (zero? (call-data-call-count data))
              (positive? (call-data-cum-sample-count data)))
         (simple-format #t
                        "==[~A ~A ~A]\n"
                        (call-data-name data)
                        (call-data-call-count data)
                        (call-data-cum-sample-count data))))
   #f)
  (simple-format #t "Total time: ~A\n" (statprof-accumulated-time))
  (simple-format #t "Sample count: ~A\n" (statprof-sample-count)))

(define (statprof-accumulated-time)
  "Returns the time accumulated during the last statprof run.@code{}"
  (if (positive? profile-level)
      (error "Can't get accumulated time while profiler is running."))
  (/ accumulated-time internal-time-units-per-second))

(define (statprof-sample-count)
  "Returns the number of samples taken during the last statprof run.@code{}"
  (if (positive? profile-level)
      (error "Can't get accumulated time while profiler is running."))
  sample-count)

(define statprof-call-data-name call-data-name)
(define statprof-call-data-calls call-data-call-count)
(define statprof-call-data-cum-samples call-data-cum-sample-count)
(define statprof-call-data-self-samples call-data-self-sample-count)

(define (statprof-fetch-stacks)
  "Returns a list of stacks, as they were captured since the last call
to @code{statprof-reset}.

Note that stacks are only collected if the @var{full-stacks?} argument
to @code{statprof-reset} is true."
  stacks)

(define procedure=?
  (lambda (a b)
    (cond
     ((eq? a b))
     ((and (program? a) (program? b))
      (eq? (program-objcode a) (program-objcode b)))
     (else
      #f))))

;; tree ::= (car n . tree*)

(define (lists->trees lists equal?)
  (let lp ((in lists) (n-terminal 0) (tails '()))
    (cond
     ((null? in)
      (let ((trees (map (lambda (tail)
                          (cons (car tail)
                                (lists->trees (cdr tail) equal?)))
                        tails)))
        (cons (apply + n-terminal (map cadr trees))
              (sort trees
                    (lambda (a b) (> (cadr a) (cadr b)))))))
     ((null? (car in))
      (lp (cdr in) (1+ n-terminal) tails))
     ((find (lambda (x) (equal? (car x) (caar in)))
            tails)
      => (lambda (tail)
           (lp (cdr in)
               n-terminal
               (assq-set! tails
                          (car tail)
                          (cons (cdar in) (cdr tail))))))
     (else
      (lp (cdr in)
          n-terminal
          (acons (caar in) (list (cdar in)) tails))))))

(define (stack->procedures stack)
  (filter identity
          (unfold-right (lambda (x) (not x))
                        frame-procedure
                        frame-previous
                        (stack-ref stack 0))))

(define (statprof-fetch-call-tree)
  "Return a call tree for the previous statprof run.

The return value is a list of nodes, each of which is of the type:
@code
 node ::= (@var{proc} @var{count} . @var{nodes})
@end code"
  (cons #t (lists->trees (map stack->procedures stacks) procedure=?)))

(define* (statprof thunk #:key (loop 1) (hz 100) (count-calls? #f)
                   (full-stacks? #f))
  "Profiles the execution of @var{thunk}.

The stack will be sampled @var{hz} times per second, and the thunk itself will
be called @var{loop} times.

If @var{count-calls?} is true, all procedure calls will be recorded. This
operation is somewhat expensive.

If @var{full-stacks?} is true, at each sample, statprof will store away the
whole call tree, for later analysis. Use @code{statprof-fetch-stacks} or
@code{statprof-fetch-call-tree} to retrieve the last-stored stacks."
  
  (dynamic-wind
    (lambda ()
      (statprof-reset (inexact->exact (floor (/ 1 hz)))
                      (inexact->exact (* 1e6 (- (/ 1 hz)
                                                (floor (/ 1 hz)))))
                      count-calls?
                      full-stacks?)
      (statprof-start))
    (lambda ()
      (let lp ((i loop))
        (if (not (zero? i))
            (begin
              (thunk)
              (lp (1- i))))))
    (lambda ()
      (statprof-stop)
      (statprof-display)
      (set! procedure-data #f))))

(define-macro (with-statprof . args)
  "Profiles the expressions in its body.

Keyword arguments:

@table @code
@item #:loop
Execute the body @var{loop} number of times, or @code{#f} for no looping

default: @code{#f}
@item #:hz
Sampling rate

default: @code{20}
@item #:count-calls?
Whether to instrument each function call (expensive)

default: @code{#f}
@item #:full-stacks?
Whether to collect away all sampled stacks into a list

default: @code{#f}
@end table"
  (define (kw-arg-ref kw args def)
    (cond
     ((null? args) (error "Invalid macro body"))
     ((keyword? (car args))
      (if (eq? (car args) kw)
          (cadr args)
          (kw-arg-ref kw (cddr args) def)))
     ((eq? kw #f def) ;; asking for the body
      args)
     (else def))) ;; kw not found
  `((@ (statprof) statprof)
    (lambda () ,@(kw-arg-ref #f args #f))
    #:loop ,(kw-arg-ref #:loop args 1)
    #:hz ,(kw-arg-ref #:hz args 100)
    #:count-calls? ,(kw-arg-ref #:count-calls? args #f)
    #:full-stacks? ,(kw-arg-ref #:full-stacks? args #f)))

(define* (gcprof thunk #:key (loop 1) (full-stacks? #f))
  "Do an allocation profile of the execution of @var{thunk}.

The stack will be sampled soon after every garbage collection, yielding
an approximate idea of what is causing allocation in your program.

Since GC does not occur very frequently, you may need to use the
@var{loop} parameter, to cause @var{thunk} to be called @var{loop}
times.

If @var{full-stacks?} is true, at each sample, statprof will store away the
whole call tree, for later analysis. Use @code{statprof-fetch-stacks} or
@code{statprof-fetch-call-tree} to retrieve the last-stored stacks."
  
  (define (reset)
    (if (positive? profile-level)
        (error "Can't reset profiler while profiler is running."))
    (set! accumulated-time 0)
    (set! last-start-time #f)
    (set! sample-count 0)
    (set! %count-calls? #f)
    (set! procedure-data (make-hash-table 131))
    (set! record-full-stacks? full-stacks?)
    (set! stacks '()))

  (define (gc-callback)
    (cond
     (inside-profiler?)
     (else
      (set! inside-profiler? #t)

      ;; FIXME: should be able to set an outer frame for the stack cut
      (let ((stop-time (get-internal-run-time))
            ;; Cut down to gc-callback, and then one before (the
            ;; after-gc async).  See the note in profile-signal-handler
            ;; also.
            (stack (or (make-stack #t gc-callback 0 1)
                       (pk 'what! (make-stack #t)))))
        (sample-stack-procs stack)
        (accumulate-time stop-time)
        (set! last-start-time (get-internal-run-time)))
      
      (set! inside-profiler? #f))))

  (define (start)
    (set! profile-level (+ profile-level 1))
    (if (= profile-level 1)
        (begin
          (set! remaining-prof-time #f)
          (set! last-start-time (get-internal-run-time))
          (set! gc-time-taken (cdr (assq 'gc-time-taken (gc-stats))))
          (add-hook! after-gc-hook gc-callback)
          (set-vm-trace-level! (the-vm) (1+ (vm-trace-level (the-vm))))
          #t)))

  (define (stop)
    (set! profile-level (- profile-level 1))
    (if (zero? profile-level)
        (begin
          (set! gc-time-taken
                (- (cdr (assq 'gc-time-taken (gc-stats))) gc-time-taken))
          (remove-hook! after-gc-hook gc-callback)
          (accumulate-time (get-internal-run-time))
          (set! last-start-time #f))))

  (dynamic-wind
    (lambda ()
      (reset)
      (start))
    (lambda ()
      (let lp ((i loop))
        (if (not (zero? i))
            (begin
              (thunk)
              (lp (1- i))))))
    (lambda ()
      (stop)
      (statprof-display)
      (set! procedure-data #f))))