aboutsummaryrefslogtreecommitdiff
path: root/src/interp/clam.boot
blob: 6a014d9ff42bacff34c7cd5e4c0126133c22578f (plain)
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
-- Copyright (c) 1991-2002, The Numerical Algorithms Group Ltd.
-- All rights reserved.
-- Copyright (C) 2007-2011, Gabriel Dos Reis.
-- All rights reserved.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are
-- met:
--
--     - Redistributions of source code must retain the above copyright
--       notice, this list of conditions and the following disclaimer.
--
--     - Redistributions in binary form must reproduce the above copyright
--       notice, this list of conditions and the following disclaimer in
--       the documentation and/or other materials provided with the
--       distribution.
--
--     - Neither the name of The Numerical Algorithms Group Ltd. nor the
--       names of its contributors may be used to endorse or promote products
--       derived from this software without specific prior written permission.
--
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
-- IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
-- TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
-- PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
-- OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-- EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-- PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
-- PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
-- LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
-- NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


import g_-timer
namespace BOOT

--% Cache Lambda Facility
-- for remembering previous values to functions
 
--to CLAM a function f, there must be an entry on $clamList as follows:
--    (functionName  --the name of the function to be CLAMed (e.g. f)
--     kind          --"hash" or number of values to be stored in
--                     circular list
--     eqEtc         --the equal function to be used
--                     (EQ, EQUAL, UEQUAL,..)
--     "shift"       --(opt) for circular lists, shift most recently
--                      used to front
--     "count")      --(opt) use reference counts (see below)
--
-- Notes:
--   Functions with "hash" as kind must give EQ, CVEC, or UEQUAL
--   Functions with some other <identifier> as kind hashed as property
--   lists with eqEtc used to compare entries
--   Functions which have 0 arguments may only be CLAMmed when kind is
--   identifier other than hash (circular/private hashtable for no args
--   makes no sense)
--
--   Functions which have more than 1 argument must never be CLAMed with EQ
--     since arguments are cached as lists
--   For circular lists, "count" will do "shift"ing; entries with lowest
--     use count are replaced
--   For cache option without "count", all entries are cleared on garbage
--     collection; For cache option with "count",
--     entries have their use count set
--     to 0 on garbage collection; those with 0 use count at garbage collection
--     are cleared
-- see definition of backendCompile2 in c-util which calls clamComp below

++
$hashNode := [[]]

++
$failed := '"failed"
 
-- see SETQ LISP for initial def of $hashNode
 
compClam(op,argl,body,$clamList) ==
  --similar to reportFunctionCompilation in SLAM BOOT
  if $InteractiveMode then startTimingProcess 'compilation
  if (u:= LASSQ(op,$clamList)) isnt [kind,eqEtc,:options]
    then keyedSystemError("S2GE0004",[op])
  $clamList:= nil            --clear to avoid looping
  if u:= S_-(options,'(shift count)) then
    keyedSystemError("S2GE0006",[op,:u])
  shiftFl := 'shift in options
  countFl := 'count in options
  if #argl > 1 and eqEtc= 'EQ then
    keyedSystemError("S2GE0007",[op])
  (not IDENTP kind) and (not integer? kind or kind < 1) =>
    keyedSystemError("S2GE0005",[op])
  IDENTP kind =>
    shiftFl => keyedSystemError("S2GE0008",[op])
    compHash(op,argl,body,(kind='hash => nil; kind),eqEtc,countFl)
  cacheCount:= kind
  if null argl then keyedSystemError("S2GE0009",[op])
  phrase:=
    cacheCount=1 => ['"computed value only"]
    [:bright cacheCount,'"computed values"]
  sayBrightly [:bright op,'"will save last",:phrase]
  auxfn:= INTERNL(op,'";")
  g1:= gensym()  --argument or argument list
  [arg,computeValue] :=
    argl is [.] => [[g1],[auxfn,g1]]  --g1 is a parameter
    [g1,['APPLX,['function,auxfn],g1]]          --g1 is a parameter list
  cacheName:= mkCacheName op
  if $reportCounts=true then
    hitCounter:= INTERNL(op,'";hit")
    callCounter:= INTERNL(op,'";calls")
    setDynamicBinding(hitCounter,0)
    setDynamicBinding(callCounter,0)
    callCountCode:= [['%store,callCounter,['%iinc,callCounter]]]
    hitCountCode:=  [['%store,hitCounter,['%iinc,hitCounter]]]
  g2:= gensym()  --length of cache or arg-value pair
  g3:= gensym()  --value computed by calling function
  lookUpFunction:=
    shiftFl =>
      countFl => 'assocCacheShiftCount
      'assocCacheShift
    countFl => 'assocCacheCount
    'assocCache
  returnFoundValue:=
    countFl => ['CDDR,g3]
    ['%tail,g3]
  namePart:=
    countFl => cacheName
    MKQ cacheName
  secondPredPair:=
--   null argl => [cacheName]
    [['%store,g3,[lookUpFunction,g1,namePart,eqEtc]],
      :hitCountCode,
        returnFoundValue]
  resetCacheEntry:=
    countFl => ['%pair,1,g2]
    g2
  thirdPredPair:=
    ['%otherwise,
      ['%store,g2,computeValue],
        ['%store,g3,['%head,cacheName]],
          ['%store,['%head,g3],g1],
            ['%store,['%tail,g3],resetCacheEntry],
              g2]
  codeBody:= ['PROG,[g2,g3],
                :callCountCode,
                  ['RETURN,['%when,secondPredPair,thirdPredPair]]]
  lamex:= ['LAM,arg,codeBody]
  mainFunction:= [op,lamex]
  computeFunction:= [auxfn,['LAMBDA,argl,:body]]
 
  -- compile generated function stub
  compileInteractive mainFunction
 
  -- compile main body: this has already been compTran'ed
  if $reportCompilation then
    sayBrightlyI bright '"Generated LISP code for function:"
    pp computeFunction
  compileQuietly [computeFunction]
 
  cacheType:= 'function
  cacheResetCode:= ['%store,cacheName,['initCache,cacheCount]]
  cacheCountCode:= ['countCircularAlist,cacheName,cacheCount]
  cacheVector:= mkCacheVec(op,cacheName,cacheType,
    cacheResetCode,cacheCountCode)
  LAM_,EVALANDFILEACTQ ['PUT, MKQ op, MKQ 'cacheInfo, MKQ cacheVector]
  LAM_,EVALANDFILEACTQ cacheResetCode
  if $InteractiveMode then stopTimingProcess 'compilation
  op
 
compHash(op,argl,body,cacheNameOrNil,eqEtc,countFl) ==
  --Note: when cacheNameOrNil~=nil, it names a global hashtable
 
-- cacheNameOrNil => compHashGlobal(op,argl,body,cacheNameOrNil,eqEtc,countFl)
--   This branch to compHashGlobal is now omitted; as a result,
--   entries will be stored on the global hashtable in a uniform way:
--        (<argument list>, <reference count>,:<value>)
--   where the reference count is optional
 
  if cacheNameOrNil and cacheNameOrNil ~= '_$ConstructorCache then
    keyedSystemError("S2GE0010",[op])
    --restriction due to omission of call to hputNewValue (see *** lines below)
 
  if null argl then
    null cacheNameOrNil => keyedSystemError("S2GE0011",[op])
    nil
  (not cacheNameOrNil) and not (eqEtc in '(EQ EQL EQUAL CVEC UEQUAL)) =>
    keyedSystemError("S2GE0012",[op])
--withWithout := (countFl => "with"; "without")
--middle:=
--  cacheNameOrNil => ["on","%b",cacheNameOrNil,"%d"]
--  '"privately "
--sayBrightly
--  ["%b",op,"%d","hashes ",:middle,withWithout," reference counts"]
  auxfn:= INTERNL(op,'";")
  g1:= gensym()  --argument or argument list
  [arg,cacheArgKey,computeValue] :=
  --    arg: to be used as formal argument of lambda construction;
  --    cacheArgKey: the form used to look up the value in the cache
  --    computeValue: the form used to compute the value from arg
    null argl => [nil,nil,[auxfn]]
    argl is [.] =>
      key:= (cacheNameOrNil => ['devaluate,g1]; g1)
      [[g1],['%list,key],[auxfn,g1]]  --g1 is a parameter
    key:= (cacheNameOrNil => ['devaluateList,g1] ; g1)
    [g1,key,['APPLY,['function,auxfn],g1]]   --g1 is a parameter list
  cacheName:= cacheNameOrNil or mkCacheName op
  if $reportCounts=true then
    hitCounter:= INTERNL(op,'";hit")
    callCounter:= INTERNL(op,'";calls")
    setDynamicBinding(hitCounter,0)
    setDynamicBinding(callCounter,0)
    callCountCode:= [['%store,callCounter,['%iinc,callCounter]]]
    hitCountCode:=  [['%store,hitCounter,['%iinc,hitCounter]]]
  g2:= gensym()  --value computed by calling function
  returnFoundValue:=
    null argl =>
    --  if we have a global hastable, functions with no arguments are
    --  stored in the same format as those with several arguments, e.g.
    --  to cache the value <val> given by f(), the structure
    --  ((nil <count> <val>)) is stored in the cache
      countFl => ['CDRwithIncrement,['CDAR,g2]]
      ['CDAR,g2]
    countFl => ['CDRwithIncrement,g2]
    g2
  getCode:=
    null argl => ['HGET,cacheName,MKQ op]
    cacheNameOrNil =>
      eqEtc ~= 'EQUAL =>
        ['lassocShiftWithFunction,cacheArgKey,
          ['HGET,cacheNameOrNil,MKQ op],MKQ eqEtc]
      ['lassocShift,cacheArgKey,['HGET,cacheNameOrNil,MKQ op]]
    ['HGET,cacheName,g1]
  secondPredPair:= [g2,optSEQ ['SEQ,:hitCountCode,['EXIT,returnFoundValue]]]
  putCode:=
    null argl =>
      cacheNameOrNil =>
        countFl =>
          ['CDDAR,['HPUT,cacheNameOrNil,MKQ op,
            ['%list,['%pair,'%nil,['%pair,1,computeValue]]]]]
        ['HPUT,cacheNameOrNil,MKQ op,
          ['%list,['%pair,'%nil,computeValue]]]
      systemError '"unexpected"
    cacheNameOrNil => computeValue
    countFl => ['%tail,['HPUT,cacheName,g1,['%pair,1,computeValue]]]
    ['HPUT,cacheName,g1,computeValue]
  if cacheNameOrNil then putCode :=
     ['UNWIND_-PROTECT,['PROG1,putCode,['%store,g2,'%true]],
                  ['%when,[['%not,g2],['HREM,cacheName,MKQ op]]]]
  thirdPredPair:= ['%otherwise,putCode]
  codeBody:= optSEQ
    ['SEQ,:callCountCode,
      ['EXIT,['%bind,[[g2,getCode]],['%when,secondPredPair,thirdPredPair]]]]
  lamex:= ['LAM,arg,codeBody]
  mainFunction:= [op,lamex]
  computeFunction:= [auxfn,['LAMBDA,argl,:body]]
 
  -- compile generated function stub
  compileInteractive mainFunction
 
  -- compile main body: this has already been compTran'ed
  if $reportCompilation then
    sayBrightlyI bright '"Generated LISP code for function:"
    pp computeFunction
  compileQuietly [computeFunction]
 
  if null cacheNameOrNil then
    cacheType:=
      countFl => 'hash_-tableWithCounts
      'hash_-table
    weakStrong:= (countFl => 'STRONG; 'WEAK)
      --note: WEAK means that key/value pairs disappear at garbage collection
    cacheResetCode:=
      ['SETQ,cacheName,['hashTable,MKQ eqEtc]]
    cacheCountCode:= ['hashCount,cacheName]
    cacheVector:=
      mkCacheVec(op,cacheName,cacheType,cacheResetCode,cacheCountCode)
    LAM_,EVALANDFILEACTQ ['PUT, MKQ op, MKQ 'cacheInfo, MKQ cacheVector]
    LAM_,EVALANDFILEACTQ cacheResetCode
  op
 
compHashGlobal(op,argl,body,cacheName,eqEtc,countFl) ==
  --Note: when cacheNameOrNil~=nil, it names a global hashtable
 
  if (not (eqEtc in '(UEQUAL))) then
    sayBrightly "for hash option, only EQ, CVEC, and UEQUAL are allowed"
  auxfn:= INTERNL(op,'";")
  g1:= gensym()  --argument or argument list
  [arg,cacheArgKey,computeValue] :=
  --    arg: to be used as formal argument of lambda construction;
  --    cacheArgKey: the form used to look up the value in the cache
  --    computeValue: the form used to compute the value from arg
    application:=
      null argl => [auxfn]
      argl is [.] => [auxfn,g1]  --g1 is a parameter
      ['APPLX,['function,auxfn],g1]          --g1 is a parameter list
    [g1,['consForHashLookup,MKQ op,g1],application]
  g2 := gensym()  --value computed by calling function
  returnFoundValue:=
    countFl => ['CDRwithIncrement,g2]
    g2
  getCode:= ['HGET,cacheName,cacheArgKey]
  secondPredPair:= [g2,returnFoundValue]
  putForm:= ['%pair,MKQ op,g1]
  putCode:=
    countFl => ['HPUT,cacheName,putForm,['%pair,1,computeValue]]
    ['HPUT,cacheName,putForm,computeValue]
  thirdPredPair := ['%otherwise,putCode]
  codeBody := ['%bind,[[g2,getCode]],['%when,secondPredPair,thirdPredPair]]
  lamex := ['LAM,arg,codeBody]
  mainFunction:= [op,lamex]
  computeFunction:= [auxfn,['LAMBDA,argl,:body]]
  compileInteractive mainFunction
  compileInteractive computeFunction
  op
 
consForHashLookup(a,b) ==
  $hashNode.first := a
  $hashNode.rest := b
  $hashNode
 
CDRwithIncrement x ==
  x.first := first x + 1
  rest x
 
HGETandCount(hashTable,prop) ==
  u:= HGET(hashTable,prop) or return nil
  u.first := first u + 1
  u
 
clearClams() ==
  for [fn,kind,:.] in $clamList | kind = 'hash or integer? kind repeat
    clearClam fn
 
clearClam fn ==
  infovec:= GETL(fn,'cacheInfo) or keyedSystemError("S2GE0003",[fn])
  eval infovec.cacheReset

reportAndClearClams() ==
  cacheStats()
  clearClams()
 
clearConstructorCaches() ==
  clearCategoryCaches()
  CLRHASH $ConstructorCache
 
clearConstructorCache(cname) ==
  (kind := getConstructorKindFromDB cname) =>
    kind = "category" => clearCategoryCache cname
    HREM($ConstructorCache,cname)
 
clearConstructorAndLisplibCaches() ==
  clearClams()
  clearConstructorCaches()
 
clearCategoryCaches() ==
  for name in allConstructors() repeat
    if getConstructorKindFromDB name = "category" then
      if BOUNDP(cacheName:= mkCacheName name)
            then setDynamicBinding(cacheName,nil)
    if BOUNDP(cacheName:= INTERNL strconc(symbolName name,'";CAT"))
          then setDynamicBinding(cacheName,nil)
 
clearCategoryCache catName ==
  setDynamicBinding(mkCacheName catName,nil)
 
displayHashtable x ==
  l:= nreverse SORTBY('CAR,[[opOf HGET(x,key),key] for key in HKEYS x])
  for [a,b] in l repeat
    sayBrightlyNT ['"%b",a,'"%d"]
    pp b
 
cacheStats() ==
  for [fn,kind,:u] in $clamList repeat
    not ('count in u) =>
      sayBrightly ["%b",fn,"%d","does not keep reference counts"]
    integer? kind => reportCircularCacheStats(fn,kind)
    kind = 'hash => reportHashCacheStats fn
    sayBrightly ["Unknown cache type for","%b",fn,"%d"]
 
reportCircularCacheStats(fn,n) ==
  infovec:= GETL(fn,'cacheInfo)
  circList:= eval infovec.cacheName
  numberUsed :=
    +/[1 for i in 1..n for x in circList while x isnt ['_$failed,:.]]
  sayBrightly ["%b",fn,"%d","has","%b",numberUsed,"%d","/ ",n," values cached"]
  displayCacheFrequency mkCircularCountAlist(circList,n)
  TERPRI()
 
displayCacheFrequency al ==
  al := nreverse SORTBY('CAR,al)
  sayBrightlyNT "    #hits/#occurrences: "
  for [a,:b] in al repeat sayBrightlyNT [a,"/",b,"  "]
  TERPRI()
 
mkCircularCountAlist(cl,len) ==
  for [x,count,:.] in cl for i in 1..len while x ~= '_$failed repeat
    u:= assoc(count,al) => u.rest := 1 + rest u
    if integer? $reportFavoritesIfNumber and count >= $reportFavoritesIfNumber then
      sayBrightlyNT ["   ",count,"  "]
      pp x
    al:= [[count,:1],:al]
  al
 
reportHashCacheStats fn ==
  infovec:= GETL(fn,'cacheInfo)
  hashTable:= eval infovec.cacheName
  hashValues:= [HGET(hashTable,key) for key in HKEYS hashTable]
  sayBrightly [:bright fn,'"has",:bright(# hashValues),'"values cached."]
  displayCacheFrequency mkHashCountAlist hashValues
  TERPRI()
 
mkHashCountAlist vl ==
  for [count,:.] in vl repeat
    u:= assoc(count,al) => u.rest := 1 + rest u
    al:= [[count,:1],:al]
  al
 
clearHashReferenceCounts() ==
  --free all cells with 0 reference counts; clear other counts to 0
  for x in $clamList repeat
    x.cacheType='hash_-tableWithCounts =>
      remHashEntriesWith0Count eval x.cacheName
    x.cacheType='hash_-table => CLRHASH eval x.cacheName
 
remHashEntriesWith0Count $hashTable ==
  MAPHASH(function fn,$hashTable) where fn(key,obj) ==
    first obj = 0 => HREM($hashTable,key)  --free store
    nil
 
initCache n ==
  tail:= '(0 . $failed)
  l:= [[$failed,:tail] for i in 1..n]
  lastNode(l).rest := l
 
assocCache(x,cacheName,fn) ==
  --fn=equality function; do not SHIFT or COUNT
  al:= eval cacheName
  forwardPointer:= al
  val:= nil
  until EQ(forwardPointer,al) repeat
    FUNCALL(fn,CAAR forwardPointer,x) => return (val:= first forwardPointer)
    backPointer:= forwardPointer
    forwardPointer:= rest forwardPointer
  val => val
  setDynamicBinding(cacheName,backPointer)
  nil
 
assocCacheShift(x,cacheName,fn) ==  --like ASSOC except that al is circular
  --fn=equality function; SHIFT but do not COUNT
  al:= eval cacheName
  forwardPointer:= al
  val:= nil
  until EQ(forwardPointer,al) repeat
    FUNCALL(fn, first (y:=first forwardPointer),x) =>
      if not EQ(forwardPointer,al) then   --shift referenced entry to front
        forwardPointer.first := first al
        al.first := y
      return (val:= y)
    backPointer := forwardPointer      --first is slot replaced on failure
    forwardPointer:= rest forwardPointer
  val => val
  setDynamicBinding(cacheName,backPointer)
  nil
 
assocCacheShiftCount(x,al,fn) ==
  -- if x is found, entry containing x becomes first element of list; if
  -- x is not found, entry with smallest use count is shifted to front so
  -- as to be replaced
  --fn=equality function; COUNT and SHIFT
  forwardPointer:= al
  val:= nil
  minCount:= 10000 --preset minCount but not newFrontPointer here
  until EQ(forwardPointer,al) repeat
    FUNCALL(fn, first (y:=first forwardPointer),x) =>
      newFrontPointer := forwardPointer
      y.rest.first := second y + 1         --increment use count
      return (val:= y)
    if QSLESSP(c := second y,minCount) then --initial c is 1 so is true 1st time
      minCount := c
      newFrontPointer := forwardPointer   --CAR is slot replaced on failure
    forwardPointer:= rest forwardPointer
  if not EQ(newFrontPointer,al) then       --shift referenced entry to front
    temp:= first newFrontPointer           --or entry with smallest count
    newFrontPointer.first := first al
    al.first := temp
  val
 
clamStats() ==
  for [op,kind,:.] in $clamList repeat
    cacheVec:= GETL(op,'cacheInfo) or systemErrorHere ["clamStats",op]
    prefix:=
      $reportCounts ~= true => nil
      hitCounter:= INTERNL(op,'";hit")
      callCounter:= INTERNL(op,'";calls")
      res:= ["%b",eval hitCounter,"/",eval callCounter,"%d","calls to "]
      setDynamicBinding(hitCounter,0)
      setDynamicBinding(callCounter,0)
      res
    postString:=
      cacheValue:= eval cacheVec.cacheName
      kind = 'hash => [" (","%b",HASH_-TABLE_-COUNT cacheValue,"%d","entries)"]
      empties:= numberOfEmptySlots eval cacheVec.cacheName
      empties = 0 => nil
      [" (","%b",kind-empties,"/",kind,"%d","slots used)"]
    sayBrightly
      [:prefix,op,:postString]
 
numberOfEmptySlots cache==
  count:= (CAAR cache ='$failed => 1; 0)
  for x in tails rest cache while NE(x,cache) repeat
    if CAAR x='$failed then count:= count+1
  count
 
addToSlam([name,:argnames],shell) ==
  $mutableDomain => return nil
  null argnames => addToConstructorCache(name,nil,shell)
  args:= ['LIST,:[mkDevaluate a for a in argnames]]
  addToConstructorCache(name,args,shell)
 
addToConstructorCache(op,args,value) ==
  ['haddProp,'$ConstructorCache,MKQ op,args,['CONS,1,value]]
 
haddProp(ht,op,prop,val) ==
  --presently, ht always = $ConstructorCache
  statRecordInstantiationEvent()
  if $reportInstantiations = true or $reportEachInstantiation = true then
    startTimingProcess 'debug
    recordInstantiation(op,prop,false)
    stopTimingProcess 'debug
  u:= HGET(ht,op) =>     --hope that one exists most of the time
    assoc(prop,u) => val     --value is already there--must = val; exit now
    u.rest := [first u,:rest u]
    u.first := [prop,:val]
    $op: local := op
    listTruncate(u,20)        --save at most 20 instantiations
    val
  HPUT(ht,op,[[prop,:val]])
  val
 
recordInstantiation(op,prop,dropIfTrue) ==
  startTimingProcess 'debug
  recordInstantiation1(op,prop,dropIfTrue)
  stopTimingProcess 'debug
 
recordInstantiation1(op,prop,dropIfTrue) ==
  op in '(CategoryDefaults RepeatedSquaring) => nil--ignore defaults for now
  if $reportEachInstantiation = true then
    trailer:= (dropIfTrue => '"  dropped"; '"  instantiated")
    if $insideCoerceInteractive= true then
      $instantCoerceCount:= 1+$instantCoerceCount
    if $insideCanCoerceFrom is [m1,m2] and null dropIfTrue then
      $instantCanCoerceCount:= 1+$instantCanCoerceCount
      xtra:=
        ['" for ",outputDomainConstructor m1,'"-->",outputDomainConstructor m2]
    if $insideEvalMmCondIfTrue = true and null dropIfTrue then
      $instantMmCondCount:= $instantMmCondCount + 1
    typeTimePrin ["CONCAT",outputDomainConstructor [op,:prop],trailer,:xtra]
  null $reportInstantiations => nil
  u:= HGET($instantRecord,op) =>     --hope that one exists most of the time
    v := LASSOC(prop,u) =>
      dropIfTrue => v.rest := 1+rest v
      v.first := 1+first v
    u.rest := [first u,:rest u]
    val :=
      dropIfTrue => [0,:1]
      [1,:0]
    u.first := [prop,:val]
  val :=
    dropIfTrue => [0,:1]
    [1,:0]
  HPUT($instantRecord,op,[[prop,:val]])
 
reportInstantiations() ==
  --assumed to be a hashtable with reference counts
    conList:=
      [:[[n,m,[key,:argList]] for [argList,n,:m] in HGET($instantRecord,key)]
        for key in HKEYS $instantRecord]
    sayBrightly ['"# instantiated/# dropped/domain name",
      "%l",'"------------------------------------"]
    nTotal:= mTotal:= rTotal := nForms:= 0
    for [n,m,form] in nreverse SORTBY('CADDR,conList) repeat
      nTotal:= nTotal+n; mTotal:= mTotal+m
      if n > 1 then rTotal:= rTotal + n-1
      nForms:= nForms + 1
      typeTimePrin ['CONCATB,n,m,outputDomainConstructor form]
    sayBrightly ["%b",'"Totals:","%d",nTotal,'" instantiated","%l",
      '"         ",$instantCoerceCount,'" inside coerceInteractive","%l",
       '"         ",$instantCanCoerceCount,'" inside canCoerceFrom","%l",
        '"         ",$instantMmCondCount,'" inside evalMmCond","%l",
         '"         ",rTotal,'" reinstantiated","%l",
          '"         ",mTotal,'" dropped","%l",
           '"         ",nForms,'" distinct domains instantiated/dropped"]
 
hputNewProp(ht,op,argList,val) ==
  --NOTE: obselete if lines *** are commented out
  -- Warning!!!  This function should only be called for
  -- $ConstructorCache slamming --- since it maps devaluate onto prop, an
  -- argument list
  --
  -- This function may be called when property is already there; for
  -- example, Polynomial applied to '(Integer), not finding it in the
  -- cache will invoke Polynomial to compute it; inside of Polynomial is
  -- a call to this function which will hputNewProp the property onto the
  -- cache so that when this function is called by the outer Polynomial,
  -- the value will always be there
 
  prop:= [devaluate x for x in argList]
  haddProp(ht,op,prop,val)
 
listTruncate(l,n) ==
  u:= l
  n:= n - 1
  while n ~= 0 and cons? u repeat
    n := n - 1
    u := rest u
  if cons? u then
    if cons? rest u and $reportInstantiations = true then
      recordInstantiation($op,CAADR u,true)
    u.rest := nil
  l
 
lassocShift(x,l) ==
  y:= l
  while cons? y repeat
    x = first first y => return (result := first y)
    y:= rest y
  result =>
    if not EQ(y,l) then
      y.first := first l
      l.first := result
    rest result
  nil
 
lassocShiftWithFunction(x,l,fn) ==
  y:= l
  while cons? y repeat
    FUNCALL(fn,x,first first y) => return (result := first y)
    y:= rest y
  result =>
    if not EQ(y,l) then
      y.first := first l
      l.first := result
    rest result
  nil
 
lassocShiftQ(x,l) ==
  y:= l
  while cons? y repeat
    EQ(x,first first y) => return (result := first y)
    y:= rest y
  result =>
    if not EQ(y,l) then
      y.first := first l
      l.first := result
    rest result
  nil
 
-- rassocShiftQ(x,l) ==
--   y:= l
--   while cons? y repeat
--     EQ(x,rest first y) => return (result := first y)
--     y:= rest y
--   result =>
--     if not EQ(y,l) then
--       y.first := first l
--       l.first := result
--     first result
--   nil
 
globalHashtableStats(x,sortFn) ==
  --assumed to be a hashtable with reference counts
  keys:= HKEYS x
  for key in keys repeat
    u:= HGET(x,key)
    for [argList,n,:.] in u repeat
      not integer? n =>   keyedSystemError("S2GE0013",[x])
      argList1:= [constructor2ConstructorForm x for x in argList]
      reportList:= [[n,key,argList1],:reportList]
  sayBrightly ["%b","  USE  NAME ARGS","%d"]
  for [n,fn,args] in nreverse SORTBY(sortFn,reportList) repeat
    sayBrightlyNT [:rightJustifyString(n,6),"  ",fn,": "]
    pp args
 
constructor2ConstructorForm x ==
  vector? x => x.0
  x
 
rightJustifyString(x,maxWidth) ==
  size:= entryWidth x
  size > maxWidth => keyedSystemError("S2GE0014",[x])
  [fillerSpaces(maxWidth-size," "),x]
 
domainEqualList(argl1,argl2) ==
  --function used to match argument lists of constructors
  while argl1 and argl2 repeat
    item1:= devaluate first argl1
    item2:= first argl2
    partsMatch:=
      item1 = item2 => true
      false
    null partsMatch => return nil
    argl1:= rest argl1; argl2 := rest argl2
  argl1 or argl2 => nil
  true
 
removeAllClams() ==
  for [fun,:.] in $clamList repeat
    sayBrightly ['"Un-clamming function",'"%b",fun,'"%d"]
    setDynamicBinding(fun,eval makeSymbol strconc(STRINGIMAGE fun,'";"))