Annotation of gforth/hash.fs, revision 1.5

1.1       pazsan      1: \ Hashed dictionaries                                  15jul94py
                      2: 
1.4       pazsan      3: 9 value hashbits
1.2       anton       4: 1 hashbits lshift Value Hashlen
1.1       pazsan      5: 
                      6: Variable insRule        insRule on
1.4       pazsan      7: Variable revealed
1.1       pazsan      8: 
1.4       pazsan      9: \ Memory handling                                      10oct94py
1.1       pazsan     10: 
                     11: Variable HashPointer
1.4       pazsan     12: Variable HashTable
                     13: Variable HashIndex
1.1       pazsan     14: 
1.4       pazsan     15: \ DelFix and NewFix are from bigFORTH                  15jul94py
1.1       pazsan     16: 
                     17: : DelFix ( addr root -- ) dup @ 2 pick ! ! ;
                     18: : NewFix  ( root len # -- addr )
                     19:   BEGIN  2 pick @ ?dup  0= WHILE  2dup * allocate throw
                     20:          over 0 ?DO  dup 4 pick DelFix 2 pick +  LOOP  drop
                     21:   REPEAT  >r drop r@ @ rot ! r@ swap erase r> ;
                     22: 
                     23: \ compute hash key                                     15jul94py
                     24: 
1.2       anton      25: : hash ( addr len -- key )
                     26:     hashbits (hashkey1) ;
                     27: \   (hashkey)
                     28: \   Hashlen 1- and ;
1.1       pazsan     29: 
1.2       anton      30: 
                     31: : hash-find ( addr len wordlist -- nfa / false )
                     32:     $C + @ >r
1.4       pazsan     33:     2dup hash r> xor cells HashTable @ + @ (hashfind) ;
1.1       pazsan     34: 
                     35: \ hash vocabularies                                    16jul94py
                     36: 
                     37: : lastlink! ( addr link -- )
                     38:   BEGIN  dup @ dup  WHILE  nip  REPEAT  drop ! ;
                     39: 
                     40: : (reveal ( addr voc -- )  $C + dup @ 0< IF  2drop EXIT  THEN
1.4       pazsan     41:   @ over cell+ count $1F and Hash xor cells >r
1.1       pazsan     42:   HashPointer 8 $400 NewFix
1.4       pazsan     43:   tuck cell+ ! r> HashTable @ + insRule @
                     44:   IF  dup @ 2 pick ! !  ELSE  lastlink!  THEN  revealed on ;
1.1       pazsan     45: 
                     46: : hash-reveal ( -- )  (reveal) last?  IF
                     47:   current @ (reveal  THEN ;
                     48: 
1.4       pazsan     49: : addall  ( -- )
                     50:     voclink
                     51:     BEGIN  @ dup @  WHILE  dup 'initvoc  REPEAT  drop ;
                     52: 
                     53: : clearhash  ( -- )
                     54:     HashTable @ Hashlen cells bounds
                     55:     DO  I @
                     56:         BEGIN  dup  WHILE
                     57:                dup @ swap HashPointer DelFix
                     58:         REPEAT  I !
                     59:     cell +LOOP  HashIndex off ;
                     60: 
                     61: : rehash  clearhash addall ;
                     62: : (rehash) ( addr -- )
                     63:   drop revealed @ IF  rehash revealed off  THEN ;
                     64: 
                     65: Create hashsearch  ' hash-find A, ' hash-reveal A, ' (rehash) A,
                     66: 
                     67: \ hash allocate and vocabulary initialization          10oct94py
                     68: 
                     69: : hash-alloc ( addr -- addr )  HashTable @ 0= IF
                     70:   Hashlen cells allocate throw HashTable !
                     71:   HashTable @ Hashlen cells erase THEN
                     72:   HashIndex @ over !  1 HashIndex +!
                     73:   HashIndex @ Hashlen >=
                     74:   IF  clearhash
                     75:       1 hashbits 1+ dup  to hashbits  lshift  to hashlen
                     76:       HashTable @ free
                     77:       addall
                     78:   THEN ;
1.1       pazsan     79: 
1.4       pazsan     80: : (initvoc) ( addr -- )
1.2       anton      81:     cell+ dup @ 0< IF  drop EXIT  THEN
                     82:     insRule @ >r  insRule off  hash-alloc
                     83:     3 cells - hashsearch over cell+ ! dup
                     84:     BEGIN  @ dup  WHILE  2dup swap (reveal  REPEAT
                     85:     2drop  r> insRule ! ;
1.1       pazsan     86: 
1.4       pazsan     87: ' (initvoc) IS 'initvoc
1.1       pazsan     88: 
                     89: \ Hash-Find                                            01jan93py
                     90: 
                     91: addall          \ Baum aufbauen
                     92: \ Baumsuche ist installiert.
                     93: 
1.5     ! pazsan     94: : hash-cold  ( -- ) Defers 'cold
        !            95:   HashPointer off  HashTable off  HashIndex off
        !            96:   addall ;
        !            97: ' hash-cold IS 'cold
        !            98: 
1.1       pazsan     99: : .words  ( -- )
1.4       pazsan    100:   base @ >r hex HashTable @  Hashlen 0
                    101:   DO  cr  i 2 .r ." : " dup i cells +
1.1       pazsan    102:       BEGIN  @ dup  WHILE
                    103:              dup cell+ @ .name  REPEAT  drop
                    104:   LOOP  drop r> base ! ;
                    105: 
1.2       anton     106: \ \ this stuff is for evaluating the hash function
                    107: \ : square dup * ;
                    108: 
                    109: \ : countwl  ( -- sum sumsq )
1.4       pazsan    110: \     \ gives the number of words in the current wordlist
                    111: \     \ and the sum of squares for the sublist lengths
1.2       anton     112: \     0 0
1.4       pazsan    113: \     hashtable @ Hashlen cells bounds DO
                    114: \        0 i BEGIN
                    115: \            @ dup WHILE
                    116: \            swap 1+ swap
                    117: \        REPEAT
                    118: \        drop
                    119: \        swap over square +
                    120: \        >r + r>
                    121: \        1 cells
                    122: \    +LOOP ;
1.2       anton     123: 
                    124: \ : chisq ( -- n )
1.4       pazsan    125: \     \ n should have about the same size as Hashlen
                    126: \     countwl Hashlen 2 pick */ swap - ;

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