This file is indexed.

/usr/share/hol88-2.02.19940316/contrib/SECD/constraints.ml is in hol88-contrib-source 2.02.19940316-14.

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
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
% SECD verification                                                 %
%                                                                   %
% FILE:                constraints.ml                               %
%                                                                   %
% DESCRIPTION:  Contains the constraint predicates that limit the   %
%               states that are subject to verification.            %
%                                                                   %
% USES FILES:   rt_SYS.th, top_SECD.th                              %
%                                                                   %
% Brian Graham 89.09.11                                             %
%                                                                   %
% Modifications:                                                    %
% 90.03.08 - changed the valid_codes_constraint to 14 bit values    %
%            from 9 bit values.                                     %
% 16.04.91 - BtG - updated to HOL12                                 %
% ================================================================= %
new_theory `constraints`;;

loadt `wordn`;;
load_library `integer`;;

map new_parent [`rt_SYS` ;
                `top_SECD` ];;
load_theorem `interface` `ID_THM`;;
load_theorem `cu_types` `Word9_11`;;
load_theorem `more_arith` `AND_DIST_OR`;;

map (load_definition `dp_types`)
 [ `atom_bits`
 ; `is_symbol`
 ; `is_cons`
 ];;
map (load_definition `rt_SECD`)
  [`opcode_bits`
  ];;
map (load_theorem `dp_types`)
  [`Bits28_Word28`
  ;`Word32_Induct`
  ;`bus32_symb_fields_lemma`
  ;`records_distinct`
  ;`rec_types_DISTINCT`
  ];;
load_definition `top_SECD` `nth`;;
load_definition `rt_SYS` `Store14`;;

letrec truncate i l =
 if i=0 then [] else hd l.truncate(i-1)(tl l);;

letrec seg (m,n) l =
 (if m<0 or n<m then fail
  if m=0 then truncate ((n-m)+1) l
         else seg (m-1,n-1) (tl l)
 ) ? failwith `seg`;;
% ================================================================= %
let mtime = ":num";;
let msig = ":^mtime->bool"
and w9_mvec = ":^mtime->word9"
and w14_mvec = ":^mtime->word14"
and w27_mvec = ":^mtime->word27"
and w32_mvec = ":^mtime->word32";;
let mem14_32 = ":word14->word32";;
let m14_32_mvec = ":^mtime->^mem14_32";;
let M = ":(word14,atom)mfsexp_mem";;
let M_mvec = ":^mtime->^M";;
let state = ":bool # bool";;
let state_msig = ":^mtime->^state";;
% ================================================================= %
let LD_instr9    = "#000000001"
and LD_instr28   = "#0000000000000000000000000001"
and LDC_instr9   = "#000000010"
and LDC_instr28  = "#0000000000000000000000000010"
and LDF_instr9   = "#000000011"
and LDF_instr28  = "#0000000000000000000000000011"
and AP_instr9    = "#000000100"
and AP_instr28   = "#0000000000000000000000000100"
and RTN_instr9   = "#000000101"
and RTN_instr28  = "#0000000000000000000000000101"
and DUM_instr9   = "#000000110"
and DUM_instr28  = "#0000000000000000000000000110"
and RAP_instr9   = "#000000111"
and RAP_instr28  = "#0000000000000000000000000111"
and SEL_instr9   = "#000001000"
and SEL_instr28  = "#0000000000000000000000001000"
and JOIN_instr9  = "#000001001"
and JOIN_instr28 = "#0000000000000000000000001001"
and CAR_instr9   = "#000001010"
and CAR_instr28  = "#0000000000000000000000001010"
and CDR_instr9   = "#000001011"
and CDR_instr28  = "#0000000000000000000000001011"
and ATOM_instr9  = "#000001100"
and ATOM_instr28 = "#0000000000000000000000001100"
and CONS_instr9  = "#000001101"
and CONS_instr28 = "#0000000000000000000000001101"
and EQ_instr9    = "#000001110"
and EQ_instr28   = "#0000000000000000000000001110"
and ADD_instr9   = "#000001111"
and ADD_instr28  = "#0000000000000000000000001111"
and SUB_instr9   = "#000010000"
and SUB_instr28  = "#0000000000000000000000010000"
and MUL_instr9   = "#000010001"
and MUL_instr28  = "#0000000000000000000000010001"
and DIV_instr9   = "#000010010"
and DIV_instr28  = "#0000000000000000000000010010"
and REM_instr9   = "#000010011"
and REM_instr28  = "#0000000000000000000000010011"
and LEQ_instr9   = "#000010100"
and LEQ_instr28  = "#0000000000000000000000010100"
and STOP_instr9  = "#000010101"
and STOP_instr28 = "#0000000000000000000000010101";;

timer true;;
% ================================================================= %
% Abstracting from the "state" of the rt level implementation to    %
% the top level spec state concerns only the mpc contents.  The     %
% mapping is defined only for 4 mpc values, and is an arbitrary     %
% value otherwise.                                                  %
% ================================================================= %
let state_abs = new_definition 
 (`state_abs`,
  "state_abs mpc =
      (mpc = #000010110) => idle          |  % 22 %
      (mpc = #000011000) => error0        |  % 24 %
      (mpc = #000011010) => error1        |  % 26 %
      (mpc = #000101011) => top_of_cycle  |  % 43 %
                            (@stat.F)");;

let state_abs_thm = prove_thm
(`state_abs_thm`,
 "(state_abs #000010110 = idle)         /\
  (state_abs #000011000 = error0)       /\
  (state_abs #000101011 = top_of_cycle) /\ 
  (state_abs #000011010 = error1)",
  rt[state_abs]
  THEN in_conv_tac wordn_CONV
  THEN rt[Word9_11; Bus_11; Wire_11]
  );;

let is_major_state = new_definition 
 (`is_major_state`,
  "is_major_state mpc (t:^mtime) =
      (mpc t = #000010110) \/
      (mpc t = #000011000) \/
      (mpc t = #000101011) \/
      (mpc t = #000011010)");;
      
let is_major_state_lemma = prove
("is_major_state mpc t ==>
     (state_abs (mpc t) =
      (mpc t = #000010110) => idle          |     % 22 %
      (mpc t = #000011000) => error0        |     % 24 %
      (mpc t = #000011010) => error1        |     % 26 %
   %  (mpc t = #000101011) => % top_of_cycle) "   % 43 %  ,
 prt[is_major_state; state_abs]
 THEN STRIP_TAC
 THEN art[]
 );;

%=================================================================%
% The system clock always cycles, never the shift register clock. %
%=================================================================%
let clock_constraint = new_definition
(`clock_constraint`,
 "clock_constraint (SYS_Clocked:^msig) =
  !t:^mtime. SYS_Clocked t"
 );;

%=================================================================%
% 3 reserved words always contain the symbolic constants.         %
%=================================================================%
let reserved_words_constraint = new_definition
(`reserved_words_constraint`,
 "reserved_words_constraint (mpc:^w9_mvec) (memory:^m14_32_mvec)=
  !t:^mtime. (state_abs (mpc t) = top_of_cycle) ==>
       ((memory t NIL_addr =
         bus32_symb_append #0000000000000000000000000000) /\
        (memory t T_addr   =
         bus32_symb_append #0000000000000000000000000001) /\
        (memory t F_addr   =
         bus32_symb_append #0000000000000000000000000010))"
 );;

% ================================================================= %
% A function to trace a car/cdr chain in a memory.                  %
% Note that we check that the cells are cons cells, otherwise the   %
%      path could take a 14 bit field of a symbol or number,        %
%      and end up in a meaningless memory location.                 %
% Note also that this function returns pointers to cells in memory, %
%      not the cells themselves.                                    %
% ================================================================= %
let path = new_list_rec_definition
(`path`,
 "(path (mem:word14->word32) (v:word14) [] = v) /\
  (path mem v (CONS l L) =
  (is_cons (mem v))
   => l => (path mem(cdr_bits(mem v))L)
         | (path mem(car_bits(mem v))L)
    | v)
 ");;

% ================================================================= %
% Predicate for path args for cdr'ing through free list.            %
% ================================================================= %
let all_cdr_path = new_list_rec_definition
(`all_cdr_path`,
 "(all_cdr_path [] = T) /\
  (all_cdr_path (CONS h tl) = h /\ (all_cdr_path tl))");;

% ================================================================= %
% free list is linear ending with NIL                               %
% ================================================================= %
let linear_free_list = new_definition
(`linear_free_list`,
 "linear_free_list (mem:word14->word32) (free:word14) = 
  !l1 l2. (all_cdr_path l1) /\ (all_cdr_path l2) ==>
          ~(l1 = l2) ==>
          (path mem free l1 = path mem free l2) ==>
          (path mem free l1 = NIL_addr)"
 );;

% ================================================================= %
% non intersection of cells reachable from v and those from free.   %
% ================================================================= %
let nonintersecting = new_definition
(`nonintersecting`,
 "nonintersecting (mem:word14->word32) (free:word14) (v:word14) =
  (!l1 l2. (all_cdr_path l2) ==>
           ~(path mem free l2 = NIL_addr) ==>
           ~(path mem v l1 = path mem free l2))"
 );;

% ================================================================= %
% a specific word is not in the free list.                          %
% ================================================================= %
let not_in_free_list = new_definition
(`not_in_free_list`,
 "not_in_free_list (mem:word14->word32) (free:word14) (v:word14) =
  !l. (all_cdr_path l) ==> ~(path mem free l = v)"
 );;

% ================================================================= %
% Function to require n cells in the free list.                     %
% ================================================================= %
let n_cells_in_free_list = new_definition
(`n_cells_in_free_list`,
 "n_cells_in_free_list (mem:word14->word32)(free:word14) n =
  (!n':num. (n' < n) ==>
            (is_cons (nth n' (mem o cdr_bits)(mem free))))"
 );;

% ================================================================= %
% The well formed free list, when in top_of_cycle state:            %
%  - is nonempty, containing 4 cells minimum                        %
%  - is a linear cdr-linked list                                    %
%  - does not intersect any cell in the s,e,c, or d data structures %
%  - the head of the free list is not the reserved NUM_addr.        %
% ================================================================= %
let well_formed_free_list = new_definition
(`well_formed_free_list`,
 "well_formed_free_list (memory:^m14_32_mvec) (mpc:^w9_mvec) 
                        (free:^w14_mvec) (s:^w14_mvec)
                        (e:^w14_mvec) (c:^w14_mvec) (d:^w14_mvec) =
 !t:^mtime.
   (state_abs (mpc t) = top_of_cycle) ==>
     (n_cells_in_free_list (memory t) (free t) 4) /\
     (linear_free_list (memory t) (free t)) /\
     (let nonintersecting_with_free_list =
	  (nonintersecting (memory t) (free t))
      in
      (nonintersecting_with_free_list (s t) /\
       nonintersecting_with_free_list (e t) /\
       nonintersecting_with_free_list (c t) /\
       nonintersecting_with_free_list (d t))) /\
     (not_in_free_list (memory t) (free t) NUM_addr)"
 );;

%=================================================================%
% Once initialized, there is always a valid program in memory.    %
% Presently it is written to ensure that a valid instruction      %
% opcode is in place.  This will need revision to include a       %
% requirement for valid arguments as well.                        %
%                                                                 %
%                 | next_c                                        %
%             __ _v                                               %
%      c' -->|__|__|head_c                                        %
%         ____/   \__ __                                          %
%  instr'|____|   |__|__|                                         %
%              ____/   \__ __                                     %
%             |____|   |__|__|                                    %
%                       /   \...                                  %
%                                                                 %
% The complexity of this constraint requires some consideration.  %
% Hardly any of the specific constraints here, aside from the     %
% possible instruction bit values and the requirement that the    %
% arguments to the LD instruction be a pair of positive integers  %
% when abstracted from word32 to integer, apply to the proof of   %
% the next state of the machine from the rtl view.                %
%                                                                 %
% The additional constraints on the type of records in memory     %
% (for example, that the top of s  is a cons cell for the CAR     %
% instruction) are needed for the abstracted operation to         %
% correspond to the top level description.  Would it not be       %
% better if the top level had these constraints, rather than      %
% muddying the picture here?                                      %
%                                                                 %
% How can these constraints be introduced?                        %
%                                                                 %
% 1. as part of the top level definition: i.e. the behaviour is   %
%    determined iff the constraint holds                          %
% 2. as a distinct constraint introduced in the correctness       %
%    statement:  i.e. low level constraints ==>                   %
% 		    ^SYS_imp ==>                                  %
%                     high_level_constraints                      %
% 			(on abstracted signals) ==>               %
%                     top_SECD                                    %
%                                                                 %
% The possible instruction codes are over constrained here.       %
% The full 14 bit field is defined for each instruction, while the%
% machine will work perfectly well if the high order bits are not %
% all 0's.                                                        %
%=================================================================%
let valid_codes_constraint = new_definition
(`valid_codes_constraint`,
 "valid_codes_constraint (memory:^m14_32_mvec) (mpc:^w9_mvec)
                           (c :^w14_mvec) = 
   !t:^mtime.
   (state_abs (mpc t) = top_of_cycle) ==>
     let head_c = memory t (c  t)
     in
      let instr' = (memory t) (car_bits head_c)
      and next_c = (cdr_bits head_c)
      in
       let instr = opcode_bits instr'
       in
       (((instr = ^LD_instr9) /\		       
         let arg_cons_cell = memory t (car_bits (memory t next_c))
         in
          let m_cell = memory t (car_bits arg_cons_cell)
          and n_cell = memory t (cdr_bits arg_cons_cell)
          in
          ((is_number m_cell) /\
           (is_number n_cell) /\
           (~(NEG (iVal (Bits28 (atom_bits m_cell))))) /\
           (~(NEG (iVal (Bits28 (atom_bits n_cell))))))
         ) \/
         (instr = ^LDC_instr9)  \/   (instr = ^LDF_instr9)  \/
         (instr = ^AP_instr9)   \/   (instr = ^RTN_instr9)  \/
         (instr = ^DUM_instr9)  \/   (instr = ^RAP_instr9)  \/
         (instr = ^SEL_instr9)  \/   (instr = ^JOIN_instr9) \/
         (instr = ^CAR_instr9)  \/   (instr = ^CDR_instr9)  \/
         (instr = ^ATOM_instr9) \/   (instr = ^CONS_instr9) \/
         (instr = ^EQ_instr9)   \/   (instr = ^ADD_instr9)  \/
         (instr = ^SUB_instr9)  \/
%        (instr = ^MUL_instr9)  \/   (instr = ^DIV_instr9)  \/ %
%        (instr = ^REM_instr9)  \/                             %
         (instr = ^LEQ_instr9)  \/   (instr = ^STOP_instr9))"
 );;

% ================================================================= %
% valid_codes_lemma =                                               %
% |- !memory mpc c .                                                %
%     valid_codes_constraint memory mpc c  =                        %
%     (!t.                                                          %
%       (state_abs(mpc t) = top_of_cycle) ==>                       %
%       (opcode_bits(memory t(car_bits(memory t(c  t))))            %
% 		  = #000000001) /\                                  %
%       is_number (memory t(car_bits(memory t(car_bits(memory t     %
% 		   (cdr_bits(memory t(c  t)))))))) /\               %
%       is_number (memory t(cdr_bits(memory t(car_bits(memory t     %
%                    (cdr_bits(memory t(c  t)))))))) /\             %
%       ~NEG(iVal(Bits28(atom_bits(memory t(car_bits(memory t       %
%          (car_bits(memory t(cdr_bits(memory t(c  t))))))))))) /\  %
%       ~NEG(iVal(Bits28(atom_bits(memory t(cdr_bits(memory t       %
%          (car_bits(memory t(cdr_bits(memory t(c  t))))))))))) \/  %
%       (opcode_bits(memory t(car_bits(memory t(c  t))))            %
% 		  = #000000010) \/                                  %
%       (opcode_bits(memory t(car_bits(memory t(c  t))))            %
% 		  = #000000011) \/                                  %
% 		         ...                                        %
%       (opcode_bits(memory t(car_bits(memory t(c  t))))            %
% 		  = #000010100) \/                                  %
%       (opcode_bits(memory t(car_bits(memory t(c  t))))            %
% 		  = #000010101))                                    %
% ================================================================= %
let valid_codes_lemma = save_thm
(`valid_codes_lemma`,
 ( (in_conv_rule BETA_CONV)
 o (prr[ID_THM])
 o (in_conv_rule ETA_CONV)
 o (prr[LET_DEF]))
 valid_codes_constraint
 );;

% ================================================================= %
% LD:   has an argument in c  consisting of the cons of 2 numbers,  %
%       should also have a constraint requiring there to be         %
%       long enough lists in the environment.                       %
%                                                                   %
% LDC:  has an atomic argument in c                                 %
%                                                                   %
% LDF:  has an argument in c                                        %
%                                                                   %
% AP:   closure & args on s : (car s ) and (cdr s )                 %
%           are both cons records                                   %
%                                                                   %
% RAP:  same as AP, plus                                            %
%       NIL on top of e                                             %
%                                                                   %
% DUM:  none                                                        %
%                                                                   %
% RTN:  only one arg on top of s ,                                  %
%       d  has s, e, c components,                                  %
%       nothing after RTN on c                                      %
%                                                                   %
% JOIN: d  is a cons,                                               %
%       nothing after JOIN in c                                     %
%                                                                   %
% SEL:  symbol on top of s                                          %
%       2 args in c                                                 %
%                                                                   %
% CAR, CDR:                                                         %
%       a cons record on top of s                                   %
%                                                                   %
% ATOM: one arg on top of s                                         %
%                                                                   %
% CONS, EQ:                                                         %
%       2 args on top of s                                          %
%                                                                   %
% ADD, SUB, MUL, DIV, REM, LEQ:                                     %
%       2 NUMERIC args on top of s                                  %
%                                                                   %
% STOP: last thing in control list,                                 %
%       s  is a list                                                %
% ================================================================= %
let valid_program_constraint = new_definition
(`valid_program_constraint`,
 "valid_program_constraint
  (memory:^m14_32_mvec) (mpc:^w9_mvec) (button_pin:^msig)
  (s :^w14_mvec) (e :^w14_mvec) (c :^w14_mvec) (d :^w14_mvec) = 
                           
   !t:^mtime.

   (((state_abs (mpc t) = idle) /\ button_pin t) ==>
     (is_cons (memory t NUM_addr)) /\
     (is_cons (memory t (car_bits (memory t NUM_addr))))) /\

   ((state_abs (mpc t) = top_of_cycle) ==>
     let head_c = memory t (c  t)
     in
     ((is_cons head_c) /\
      let instr' = (memory t) (car_bits head_c)
      and next_c = (cdr_bits head_c)
      in
      ((is_number instr') /\
       let instr = atom_bits instr'
       in
        (((instr = ^LD_instr28) /\	
          (is_cons (memory t next_c)) /\
          let arg_cons_cell = memory t (car_bits (memory t next_c))
          in
          ((is_cons arg_cons_cell) /\
           let m_cell = memory t (car_bits arg_cons_cell)
           and n_cell = memory t (cdr_bits arg_cons_cell)
           in
           ((is_number m_cell) /\
            (is_number n_cell) /\
            let m = (iVal(Bits28(atom_bits m_cell)))
            and n = (iVal(Bits28(atom_bits n_cell)))
            in
            ((~NEG m) /\
             (~NEG n) /\
             (!m'. (m' <= (pos_num_of m))  ==>
                   (is_cons (nth m' ((memory t) o cdr_bits)
                             (memory t (e  t))))) /\
             (!n'. (n' <= (pos_num_of n)) ==>
                   (is_cons (nth n' ((memory t) o cdr_bits)
                                 (memory t(car_bits 
                                            (nth (pos_num_of m)
                                            ((memory t) o cdr_bits)
                                            (memory t (e  t)))))))))))
         ) \/
         ((instr = ^LDC_instr28) /\	
          (is_cons (memory t next_c)) /\
          (is_atom (memory t (car_bits (memory t next_c))))
         ) \/
         ((instr = ^LDF_instr28) /\	
          (is_cons (memory t next_c)) 
         ) \/
         (((instr = ^AP_instr28) \/
           ((instr = ^RAP_instr28) /\	
            (is_cons (memory t (e  t))) /\
            (car_bits (memory t (e  t)) = NIL_addr) /\
            (e t = cdr_bits(memory t(car_bits(memory t(s t))))))) /\
          (is_cons (memory t (s  t))) /\
          (is_cons (memory t (car_bits (memory t (s  t))))) /\
          (is_cons (memory t (cdr_bits (memory t (s  t)))))
         ) \/
         ((instr = ^RTN_instr28) /\	
          (is_cons (memory t (d  t))) /\
          (is_cons (memory t (cdr_bits (memory t (d  t))))) /\
          (is_cons (memory t (cdr_bits (memory t
                              (cdr_bits (memory t (d  t))))))) /\
          (is_cons (memory t (s  t))) /\
          (next_c  = NIL_addr)
         ) \/
         (instr = ^DUM_instr28) \/
         ((instr = ^SEL_instr28) /\	
          (is_cons (memory t (s  t))) /\
          (is_symbol (memory t (car_bits (memory t (s  t))))) /\
          (is_cons (memory t next_c)) /\
          (is_cons (memory t (cdr_bits (memory t next_c))))
         ) \/
         ((instr = ^JOIN_instr28) /\	
          (is_cons (memory t (d  t))) /\
          (next_c = NIL_addr)
         ) \/
         (((instr = ^CAR_instr28) \/
           (instr = ^CDR_instr28)) /\	
          (is_cons (memory t (s  t))) /\
          (is_cons (memory t (car_bits (memory t (s  t)))))
         ) \/
         ((instr = ^ATOM_instr28) /\	
          (is_cons (memory t (s  t)))
         ) \/
         ((instr = ^CONS_instr28) /\	
          (is_cons (memory t (s  t))) /\
          (is_cons (memory t (cdr_bits (memory t (s  t)))))
         ) \/
         ((instr = ^EQ_instr28) /\	
          (is_cons (memory t (s  t))) /\
          (is_cons (memory t (cdr_bits (memory t (s  t))))) /\
          ((is_atom (memory t (car_bits (memory t (s t))))) \/
           (is_atom (memory t (car_bits (memory t (cdr_bits (memory t (s  t))))))))
         ) \/
         (((instr = ^ADD_instr28) \/
           (instr = ^SUB_instr28) \/
%          (instr = ^MUL_instr28) \/                               %
%          (instr = ^DIV_instr28) \/                               %
%          (instr = ^REM_instr28) \/                               %
           (instr = ^LEQ_instr28)) /\	
          (is_cons (memory t (s  t))) /\
          (is_cons (memory t (cdr_bits (memory t (s  t))))) /\
          (is_number (memory t (car_bits (memory t (s  t))))) /\
          (is_number (memory t (car_bits (memory t
                                (cdr_bits (memory t (s  t)))))))
         ) \/
         ((instr = ^STOP_instr28) /\	
          (is_cons (memory t (s  t))) /\
          (next_c = NIL_addr))))))"
 );;


let valid_program_lemma = save_thm
(`valid_program_lemma`,
 ( (in_conv_rule BETA_CONV)
 o (in_conv_rule ETA_CONV)
 o (prr[LET_DEF])
 o (prr[porr[CONJ_SYM] AND_DIST_OR]))
 valid_program_constraint
 );;

% ================================================================= %
% If the larger atom_bits subfields are equal then the smaller      %
% opcode_bits subfields are equal.                                  %
% ================================================================= %
let EQ_atom_IMP_EQ_opcode = prove_thm
(`EQ_atom_IMP_EQ_opcode`,
 "!w32.opcode_bits
        (Word32(Bus F(Bus F(Bus T(Bus T(Bits28(atom_bits w32))))))) =
       opcode_bits w32",
 INDUCT_THEN Word32_Induct ASSUME_TAC
 THEN REPEAT GEN_TAC
 THEN port[atom_bits]
 THEN port[Bits28_Word28]
 THEN port[opcode_bits]
 THEN REFL_TAC
 );;

% ================================================================= %
% The weaker valid_codes_constraint is implied by the stronger      %
% valid_programs_constraint.  The distinct constraints are used     %
% to explicitly minimize the constraints required for the           %
% liveness of the chip, while the more extensive constraints        %
% are needed in the proof of the correctness relating the rtl and   %
% SYS_spec.                                                         %
% ================================================================= %
let valid_program_IMP_valid_codes = prove_thm
(`valid_program_IMP_valid_codes`,
 "!memory mpc button_pin s  e  c  d .
   valid_program_constraint memory mpc button_pin s  e  c  d  ==>
     valid_codes_constraint memory mpc c ",
 REPEAT GEN_TAC
 THEN SUBST_TAC
      [SPEC_ALL valid_codes_lemma; SPEC_ALL valid_program_lemma]
 THEN DISCH_THEN
      (\th. GEN_TAC
            THEN DISCH_THEN
	         (\th1. CONJUNCTS_THEN2
	                (K ALL_TAC)
			(\th2. CONJUNCTS_THEN2
			       (K ALL_TAC)
			       (CONJUNCTS_THEN2
				(K ALL_TAC)
				(REPEAT_TCL
				 DISJ_CASES_THEN
				 (REPEAT_TCL STRIP_THM_THEN ASSUME_TAC)))
			       (MP th2 th1))
		        (SPEC_ALL th)))
 THEN FIRST_ASSUM
 (\th. is_eq (concl th) 
   => type_of (fst (dest_eq (concl th))) = ":word28"
      =>
  (SUBST1_TAC o (porr[SYM(wordn_CONV
			  (mk_const(implode(`#`.(seg(20,28)(explode
			   (fst(dest_const(snd(dest_eq
			    (concl th)))))))),":word9")))])
	      o (porr[opcode_bits])
              o (porr[Bits28_Word28])
	      o (in_conv_rule wordn_CONV)
	      o (porr [EQ_atom_IMP_EQ_opcode])
	      o (prr[o_THM])
              o (AP_TERM "opcode_bits o Word32 o (Bus F) o (Bus F)
                          o (Bus T) o (Bus T) o Bits28")) th
	      | NO_TAC | NO_TAC )
 THEN art[]
 );;

% ================================================================= %
% The NIL reserved word is a symbol.                                %
% ================================================================= %
let NIL_is_symbol = prove
("(memory NIL_addr =
   bus32_symb_append #0000000000000000000000000000) ==>
  (is_symbol (memory NIL_addr))",
 DISCH_THEN SUBST1_TAC
 THEN port[is_symbol]
 THEN port[bus32_symb_fields_lemma]
 THEN REFL_TAC
 );;

% ================================================================= %
% If NIL reserved word is in place,                                 %
% then a cons cell address is distinct from NIL_addr.               %
% ================================================================= %
let NIL_not_cons = prove_thm
(`NIL_not_cons`,
 "(memory NIL_addr =
   bus32_symb_append #0000000000000000000000000000) ==>
  !free.
   is_cons (memory free) ==> 
   ~(free = NIL_addr)",
 DISCH_THEN (ASSUME_TAC o (MATCH_MP NIL_is_symbol))
 THEN GEN_TAC
 THEN STRIP_TAC
 THEN DISCH_THEN SUBST_ALL_TAC
 THEN IMP_RES_TAC (records_distinct)
 );;

% ================================================================= %
% Derive the meaning of the n_cells_in_free_list constraint at 4.   %
% ================================================================= %
let n_cells_in_free_list_4_thm = prove_thm
(`n_cells_in_free_list_4_thm`,
 "n_cells_in_free_list mem free 4 ==>
  is_cons(mem free) /\
  is_cons(mem(cdr_bits(mem free))) /\
  is_cons(mem(cdr_bits(mem(cdr_bits(mem free))))) /\
  is_cons(mem(cdr_bits(mem(cdr_bits(mem(cdr_bits(mem free)))))))",
 port[n_cells_in_free_list]
 THEN re_conv_tac num_CONV
 THEN DISCH_THEN
 (\th. MAP_EVERY
  (\tm. port1 
        (rr[LESS_MONO_EQ; LESS_0; nth; o_THM]
	   (SPEC tm th)))
  ["0";"SUC 0";"SUC(SUC 0)";"SUC(SUC(SUC 0))"])
 THEN rt[]
 );;

% ================================================================= %
% ================================================================= %
let cons_cells_not_NIL = prove
("reserved_words_constraint mpc memory ==>
  !t.
  (state_abs(mpc t) = top_of_cycle) ==>
  !v. 
   (is_cons(memory t v) ==> ~(v = NIL_addr))",
 port[reserved_words_constraint]
 THEN DISCH_THEN
 (\th1. GEN_TAC
        THEN DISCH_THEN
	(\th2. (ASSUME_TAC
		o (porr[SYM_RULE rec_types_DISTINCT])
		o (porr[bus32_symb_fields_lemma])
		o (porr[is_cons])
		o (AP_TERM "is_cons")
		o CONJUNCT1)
	 (MATCH_MP th1 th2)))
 THEN port[is_cons]
 THEN GEN_TAC
 THEN STRIP_TAC
 THEN DISCH_THEN SUBST_ALL_TAC
 THEN RES_TAC
);;

% ================================================================= %
% To begin, a set of lemmas that constrain how much of memory is    %
% affected by sequential Store14 operations, with parts of the      %
% well_formed_free_list constraint in effect.                       %
%                                                                   %
% If x is distinct from free list cells                             %
% and free list is linear,                                          %
% then mem[n+1 writes] at x is unchanged from mem[n writes] at x,   %
%      for 0 <= n <= 3                                              %
% ================================================================= %
let Store14_1_lemma = prove_thm
(`Store14_1_lemma`,
 "!x. ~(free = x) ==>
   !z. memory x = Store14 free z memory x",
 GEN_TAC
 THEN DISCH_THEN (STRIP_ASSUME_TAC o SYM_RULE)
 THEN GEN_TAC
 THEN port[Store14]
 THEN in1_conv_tac BETA_CONV
 THEN art[]
 );;

let Store14_2_step_lemma = prove
("!x.
  ~(free = x) /\
  ~(cdr_bits(memory free) = x) ==>
  !z zz.
   Store14 free zz memory x = 
%  memory x = ****** equally provable ******* %
   Store14 (cdr_bits(memory free)) z (Store14 free zz memory) x",
 GEN_TAC
 THEN DISCH_THEN (STRIP_ASSUME_TAC o SYM_RULE)
 THEN REPEAT GEN_TAC
 THEN prt[Store14]
 THEN in_conv_tac BETA_CONV
 THEN art[]
 );;

let Store14_3_step_lemma = prove
("!x.
  ~(free = x) /\
  ~(cdr_bits(memory free) = x) /\
  ~(cdr_bits(memory(cdr_bits(memory free))) = x) /\
  ~(free = cdr_bits(memory free))
  ==>
  !z zz zzz.
   Store14 (cdr_bits(memory free)) zz (Store14 free zzz memory) x = 
   Store14(cdr_bits(Store14 free zzz memory(cdr_bits(memory free))))
          z
          (Store14(cdr_bits(memory free))
                  zz
                  (Store14 free zzz memory))
          x",
 GEN_TAC
 THEN DISCH_THEN (STRIP_ASSUME_TAC o SYM_RULE)
 THEN REPEAT GEN_TAC
 THEN prt[Store14]
 THEN in_conv_tac BETA_CONV
 THEN art[]
 );;

% ================================================================= %
% The similar versions that take the cell back to the original      %
% memory, rather than just one step...                              %
%                                                                   %
% If x is distinct from free list cells                             %
% and free list is linear,                                          %
% then mem[n+1 writes] at x is unchanged from mem[0 writes] at x,   %
%      for 1 <= n <= 3                                              %
% ================================================================= %
let Store14_2_lemma = prove_thm
(`Store14_2_lemma`,
 "!x.
  ~(free = x) /\
  ~(cdr_bits(memory free) = x) ==>
  !z zz.
   memory x = 
   Store14 (cdr_bits(memory free)) z (Store14 free zz memory) x",
 GEN_TAC
 THEN DISCH_THEN (STRIP_ASSUME_TAC o SYM_RULE)
 THEN REPEAT GEN_TAC
 THEN prt[Store14]
 THEN in_conv_tac BETA_CONV
 THEN art[]
 );;

let Store14_3_lemma = prove_thm
(`Store14_3_lemma`,
 "!x.
  ~(free = x) /\
  ~(cdr_bits(memory free) = x) /\
  ~(cdr_bits(memory(cdr_bits(memory free))) = x) /\
  ~(free = cdr_bits(memory free))
  ==>
  !z zz zzz.
   memory x = 
   Store14(cdr_bits(Store14 free zzz memory(cdr_bits(memory free))))
          z
          (Store14(cdr_bits(memory free))
                  zz
                  (Store14 free zzz memory))
          x",
 GEN_TAC
 THEN DISCH_THEN (STRIP_ASSUME_TAC o SYM_RULE)
 THEN REPEAT GEN_TAC
 THEN prt[Store14]
 THEN in_conv_tac BETA_CONV
 THEN art[]
 );;

% ================================================================= %
% Note : an error uncovered here on 90.08.29.  There was an         %
%        incorrect 1st argument to the 2nd last Store14             %
% ================================================================= %
let Store14_4_lemma = prove_thm
(`Store14_4_lemma`,
 "!x.
  ~(free = x) /\
  ~(cdr_bits(memory free) = x) /\
  ~(cdr_bits(memory(cdr_bits(memory free))) = x) /\
  ~(cdr_bits(memory(cdr_bits(memory(cdr_bits(memory free))))) = x) /\
  ~(free = cdr_bits(memory free)) /\
  ~(free = cdr_bits(memory(cdr_bits(memory free)))) /\
  ~(cdr_bits(memory free) =
    cdr_bits(memory(cdr_bits(memory free)))) ==>
  !z zz zzz zzzz.
   memory x =
   Store14(cdr_bits(Store14(cdr_bits(memory free))
                           zzz
                           (Store14 free zzzz memory)
                    (cdr_bits(Store14 free zzzz memory
                              (cdr_bits(memory free))))))
           z
           (Store14(cdr_bits(Store14 free zzzz memory
                             (cdr_bits(memory free))))
                   zz
                   (Store14(cdr_bits(memory free))
                           zzz
                           (Store14 free zzzz memory)))
           x",
 GEN_TAC
 THEN DISCH_THEN (STRIP_ASSUME_TAC o SYM_RULE)
 THEN REPEAT GEN_TAC
 THEN prt[Store14]
 THEN in_conv_tac BETA_CONV
 THEN art[]
 );;
 
% ================================================================= %
% Notice that for the 1st M_Cons, the precondition is an assumption.%
%                                                                   %
% If free list is linear and next cell is a cons,                   %
% then it remains a cons after 2-4 writes.                          %
% ================================================================= %
let M_Cons_2_precond_lemma = prove_thm
(`M_Cons_2_precond_lemma`,
 "~(free = (cdr_bits(memory free)))          /\
   is_cons(memory(cdr_bits(memory free)))    ==>
   !z. is_cons (Store14 free z memory(cdr_bits(memory free)))",
 REPEAT STRIP_TAC
 THEN IMP_RES_THEN (SUBST1_TAC o SYM o (SPEC "z:word32"))
        (SPEC "cdr_bits(memory(free:word14))" Store14_1_lemma)
 THEN art[]
 );;

let M_Cons_3_precond_lemma = prove_thm
(`M_Cons_3_precond_lemma`,
 "~(free = cdr_bits(memory free))                    /\
  ~(free = cdr_bits(memory(cdr_bits(memory free))))  /\
  ~(cdr_bits(memory free) =
    cdr_bits(memory(cdr_bits(memory free))))         /\
  is_cons(memory(cdr_bits(memory(cdr_bits(memory free))))) 
  ==>
  !z zz.
   is_cons(Store14(cdr_bits(memory free))
                  z
                  (Store14 free zz memory)
                  (cdr_bits(Store14 free zz memory
                            (cdr_bits(memory free)))))",
 DISCH_THEN
 \th.
 (\[th1;th2;th3;th4].
  REPEAT GEN_TAC
  THEN SUBST1_TAC
       (SYM_RULE
	(SPEC "zz:word32"
	      (MP (SPEC "cdr_bits(memory(free:word14))"
			Store14_1_lemma)
		  th1)))  
  THEN SUBST1_TAC
       (SYM_RULE
	(SPECL ["z:word32";"zz:word32"]
	     (MATCH_MP Store14_2_step_lemma (CONJ th2 th3))))
  THEN SUBST1_TAC
       (SYM_RULE
	(SPEC "zz:word32"
	      (MP (SPEC "cdr_bits(memory(cdr_bits(memory free)))"
			Store14_1_lemma)
		  th2)))
  THEN port1 th4
  ) (CONJUNCTS th)
 );;

let M_Cons_4_precond_lemma = prove_thm
(`M_Cons_4_precond_lemma`,
 "~(free = cdr_bits(memory free))                    /\
  ~(free = cdr_bits(memory(cdr_bits(memory free))))  /\
  ~(free =
    cdr_bits(memory(cdr_bits(memory(cdr_bits(memory free))))))  /\
  ~(cdr_bits(memory free) =
    cdr_bits(memory(cdr_bits(memory free))))         /\
  ~(cdr_bits(memory free) =
    cdr_bits(memory(cdr_bits(memory(cdr_bits(memory free))))))  /\
  ~(cdr_bits(memory(cdr_bits(memory free))) =
    cdr_bits(memory(cdr_bits(memory(cdr_bits(memory free))))))  /\
  is_cons
  (memory(cdr_bits(memory(cdr_bits(memory(cdr_bits(memory free)))))))
  ==>
  !z zz zzz.
   is_cons
   (Store14
    (cdr_bits(Store14 free zzz memory(cdr_bits(memory free))))
    z
    (Store14(cdr_bits(memory free))zz(Store14 free zzz memory))
    (cdr_bits
     (Store14
      (cdr_bits(memory free))
      zz
      (Store14 free zzz memory)
      (cdr_bits(Store14 free zzz memory(cdr_bits(memory free)))))))",
 DISCH_THEN
 (\th. let [th1;th2;th3;th4;th5;th6;th7] = CONJUNCTS th in
       let thd = MATCH_MP Store14_2_step_lemma (CONJ th2 th4)
       and thc = MATCH_MP Store14_2_step_lemma (CONJ th3 th5)
       and tha = MATCH_MP Store14_3_step_lemma (LIST_CONJ [th3;th5;th6;th1]) in
 REPEAT GEN_TAC
 THEN 
 let thm1 =
 (SYM(SPEC "zzz:word32"
	   (MP (SPEC "cdr_bits(memory (free:word14))"
		     Store14_1_lemma)
	       th1)))
 in
 (SUBST1_TAC thm1
  THEN SUBST1_TAC (SYM (SPECL ["zz:word32";"zzz:word32"] thd))
  THEN (SUBST1_TAC
       o SYM
       o (SPEC "zzz:word32"))
      (MP (SPEC "cdr_bits(memory(cdr_bits(memory free)))"
		Store14_1_lemma)
	  th2)
  THEN SUBST1_TAC (SYM (SUBS[thm1](SPEC_ALL tha)))
  THEN (SUBST1_TAC
		 o SYM
		 o (SPECL ["zz:word32";"zzz:word32"])) thc
  THEN SUBST1_TAC
      (SYM(SPEC "zzz:word32"
		(MP (SPEC "cdr_bits(memory(cdr_bits(memory(cdr_bits(memory(free:word14))))))"
			  Store14_1_lemma)
		    th3)))
  THEN port1 th7 			  
  )));;

% ================================================================= %
% ================================================================= %
% ================================================================= %
% The well formed free list constraint flattened somewhat.          %
%                                                                   %
% The first 4 conjuncts follow directly from                        %
% n_cells_in_free_list_4_thm above.                                 %
% The remaining arise from the linear_free_list constraint,         %
% and the reserved_words_constraint for NIL_addr.                   %
% By using cons_cells_not_NIL with the rhs of                       %
% n_cells_in_free_list_4_thm, we get inequalities of the cells      %
% concerned and NIL_addr.                                           %
% Next, we split into the 6 conjuncts, and specialize               %
% linear_free_list with the appropriate path function arguments to  %
% get the cells concerned.                                          %
% Simplify the term by expanding definitions, and discharge.        %
% Rewrite with the is_cons assumptions.                             %
%                                                             qed.  %
% ================================================================= %
let well_formed_free_list_lemma = prove_thm
(`well_formed_free_list_lemma`,
 "(reserved_words_constraint mpc memory /\
   well_formed_free_list memory mpc free s e c d)==>
  !t.
  (state_abs(mpc t) = top_of_cycle) ==>
  ((is_cons(memory t(free t))) /\
   (is_cons(memory t(cdr_bits(memory t(free t))))) /\
   (is_cons(memory t(cdr_bits(memory t(cdr_bits(memory t(free t))))))) /\
   (is_cons(memory t(cdr_bits(memory t(cdr_bits(memory t
                    (cdr_bits(memory t(free t))))))))) /\
   (~(free t = cdr_bits(memory t(free t)))) /\
   (~(free t = cdr_bits(memory t(cdr_bits(memory t(free t)))))) /\
   (~(free t = cdr_bits(memory t(cdr_bits(memory t
              (cdr_bits(memory t(free t)))))))) /\
   (~(cdr_bits(memory t(free t)) =
          cdr_bits(memory t(cdr_bits(memory t(free t)))))) /\
   (~(cdr_bits(memory t(free t)) = cdr_bits(memory t(cdr_bits(memory t
              (cdr_bits(memory t(free t)))))))) /\
   (~(cdr_bits(memory t(cdr_bits(memory t(free t)))) = cdr_bits(memory t(cdr_bits(memory t
              (cdr_bits(memory t(free t)))))))))",
 DISCH_THEN
 (\th1. GEN_TAC THEN DISCH_THEN
  (\th2. (CONJUNCTS_THEN2
	  (\th3.ASSUME_TAC
	   (MATCH_MP(MATCH_MP cons_cells_not_NIL th3)th2))
	  (\th4.
	   (\[a;b;c;d].STRIP_ASSUME_TAC(MATCH_MP n_cells_in_free_list_4_thm a)
	               THEN art[] THEN RES_TAC THEN ASSUME_TAC b)
	   (CONJUNCTS(MATCH_MP(porr[well_formed_free_list]th4)th2)))
	  th1)))
 THEN let th = ASSUME "linear_free_list(memory t)(free (t:num))" in
 (REPEAT CONJ_TAC
  THENL
  (map
   (\(a,b).
    ( (\th1. ASSUME_TAC th1 THEN (UNDISCH_TAC (concl th1)))
    o (rr[all_cdr_path;CONS_11;NOT_NIL_CONS;path]))
    (SPECL [a;b] (porr[linear_free_list]th)))
   ["[]:(bool)list","[T]"
   ;"[]:(bool)list","[T;T]"
   ;"[]:(bool)list","[T;T;T]"
   ;"[T]","[T;T]"
   ;"[T]","[T;T;T]"
   ;"[T;T]","[T;T;T]"
   ]))
 THEN art[]
 );;

% ================================================================= %
% This theorem gives the desired form for the proof function in     %
% mu-prog_proof_fcn.ml, to replace the original general             %
% free_list_constraint with the newer constraints.                  %
% This covers the maximum of 4 cons'es done by any sequence (AP).   %
% ================================================================= %
let free_list_constraint_thm = prove_thm
(`free_list_constraint_thm`,
 "(reserved_words_constraint mpc memory /\
   well_formed_free_list memory mpc free s e c d) ==>
   !t:num. (state_abs (mpc t) = top_of_cycle) ==>

    (((free t) = NIL_addr) = F) /\

    (((cdr_bits(memory t(free t))) = NIL_addr) = F) /\

    (!c1.
     (cdr_bits(Store14 (free t) c1
		       (memory t)
		       (cdr_bits(memory t(free t)))) =
      NIL_addr) = F) /\

    (!c1 c2.
     (cdr_bits(Store14(cdr_bits(memory t(free t)))
		      c2
		      (Store14(free t)c1(memory t))
		      (cdr_bits(Store14 (free t) c1
					(memory t)
					(cdr_bits(memory t(free t))))
		      )) = NIL_addr) = F)",
 STRIP_TAC THEN GEN_TAC
 THEN STRIP_TAC
 THEN IMP_RES_THEN (IMP_RES_THEN IMP_RES_TAC)
                   well_formed_free_list_lemma
 THEN IMP_RES_THEN (IMP_RES_THEN IMP_RES_TAC)
                   cons_cells_not_NIL
 THEN prt[Store14]
 THEN in_conv_tac BETA_CONV
 THEN REPEAT CONJ_TAC
 THEN REPEAT GEN_TAC
 THEN REPEAT (EVERY_ASSUM (port1 o SYM_RULE) THEN art[])
 );;
 
% ================================================================= %
% Another derivation of properties of well_formed_free_list; this   %
% time the nonintersection component is extracted.                  %
% ================================================================= %
let well_formed_free_list_nonintersection_lemma = prove_thm
(`well_formed_free_list_nonintersection_lemma`,
 "well_formed_free_list memory mpc free s e c d ==>
    (!t.
      (state_abs(mpc t) = top_of_cycle) ==>
      nonintersecting(memory t)(free t)(s t) /\
      nonintersecting(memory t)(free t)(e t) /\
      nonintersecting(memory t)(free t)(c t) /\
      nonintersecting(memory t)(free t)(d t))",
 port[well_formed_free_list]
 THEN STRIP_TAC
 THEN GEN_TAC
 THEN DISCH_THEN
      (ANTE_RES_THEN (port1 o (in_conv_rule BETA_CONV) o (porr[LET_DEF])))
 THEN rt[]);;

timer false;;
close_theory ();;
print_theory `-`;;