--- gforth/hash.fs	1994/07/21 10:52:43	1.1
+++ gforth/hash.fs	1997/07/06 15:55:24	1.18
@@ -1,76 +1,205 @@
 \ Hashed dictionaries                                  15jul94py
 
-$80 Value Hashlen
+\ Copyright (C) 1995 Free Software Foundation, Inc.
+
+\ This file is part of Gforth.
+
+\ Gforth is free software; you can redistribute it and/or
+\ modify it under the terms of the GNU General Public License
+\ as published by the Free Software Foundation; either version 2
+\ of the License, or (at your option) any later version.
+
+\ This program 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 General Public License for more details.
+
+\ You should have received a copy of the GNU General Public License
+\ along with this program; if not, write to the Free Software
+\ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+[IFUNDEF] e? : e? name 2drop false ; [THEN]
+
+e? ec
+[IF]
+: reserve-mem here swap allot ;
+\ ToDo: check memory space with unused
+\ move to a kernel/memory.fs
+[ELSE]
+: reserve-mem allocate throw ;
+[THEN]
+
+[IFUNDEF] hashbits
+11 value hashbits
+[THEN]
+1 hashbits lshift Value Hashlen
+
+\ compute hash key                                     15jul94py
+
+[IFUNDEF] hash
+: hash ( addr len -- key )
+    hashbits (hashkey1) ;
+[THEN]
 
 Variable insRule        insRule on
+Variable revealed
 
-\ Memory handling                                      15jul94py
+\ Memory handling                                      10oct94py
 
 Variable HashPointer
+Variable HashIndex
+0 Value HashTable
 
-: hash-alloc ( addr -- addr )  dup @ 0= IF
-  Hashlen cells allocate throw over !
-  dup @ Hashlen cells erase THEN ;
+\ forward declarations
+0 Value hashsearch-map
+Defer hash-alloc
 
-\ DelFix and NewFix is from bigFORTH                   15jul94py
+\ DelFix and NewFix are from bigFORTH                  15jul94py
 
 : DelFix ( addr root -- ) dup @ 2 pick ! ! ;
 : NewFix  ( root len # -- addr )
-  BEGIN  2 pick @ ?dup  0= WHILE  2dup * allocate throw
+  BEGIN  2 pick @ ?dup  0= WHILE  2dup * reserve-mem
          over 0 ?DO  dup 4 pick DelFix 2 pick +  LOOP  drop
   REPEAT  >r drop r@ @ rot ! r@ swap erase r> ;
 
-\ compute hash key                                     15jul94py
+: bucket ( addr len wordlist -- bucket-addr )
+    \ @var{bucket-addr} is the address of a cell that points to the first
+    \ element in the list of the bucket for the string @var{addr len}
+    wordlist-extend @ -rot hash xor ( bucket# )
+    cells HashTable + ;
 
-: hash ( addr len -- key )  (hashkey)
-\  tuck bounds  ?DO  I c@ toupper +  LOOP
-  Hashlen 1- and ;
-
-: hash-find ( addr len wordlist -- nfa / false ) $C + @ >r
-  2dup hash cells r> + @ (hashfind) ;
-\  BEGIN  dup  WHILE
-\         2@ >r >r dup r@ cell+ c@ $1F and =
-\         IF  2dup r@ cell+ char+ capscomp 0=
-\	     IF  2drop r> rdrop  EXIT  THEN  THEN
-\	 rdrop r>
-\  REPEAT nip nip ;
+: hash-find ( addr len wordlist -- nfa / false )
+    >r 2dup r> bucket @ (hashfind) ;
 
 \ hash vocabularies                                    16jul94py
 
 : lastlink! ( addr link -- )
   BEGIN  dup @ dup  WHILE  nip  REPEAT  drop ! ;
 
-: (reveal ( addr voc -- )  $C + dup @ 0< IF  2drop EXIT  THEN
-  hash-alloc @ over cell+ count $1F and Hash cells + >r
-  HashPointer 8 $400 NewFix
-  tuck cell+ ! r> insRule @
-  IF  dup @ 2 pick ! !  ELSE  lastlink!  THEN ;
-
-: hash-reveal ( -- )  (reveal) last?  IF
-  current @ (reveal  THEN ;
-
-Create hashsearch  ' hash-find A,  ' hash-reveal A,  ' drop A,
-
-: (initvoc ( addr -- )  cell+ dup @ 0< IF  drop EXIT  THEN
-  insRule @ >r  insRule off  hash-alloc
-  3 cells - hashsearch over cell+ ! dup
-  BEGIN  @ dup  WHILE  2dup swap (reveal  REPEAT
-  2drop  r> insRule ! ;
-
-' (initvoc IS 'initvoc
-
-: addall  ( -- )  voclink
-  BEGIN  @ dup @  WHILE  dup (initvoc  REPEAT  drop ;
+: (reveal ( nfa wid -- )
+    over name>string rot bucket >r
+    HashPointer 2 Cells $400 NewFix
+    tuck cell+ ! r> insRule @
+    IF
+	dup @ 2 pick ! !
+    ELSE
+	lastlink!
+    THEN
+    revealed on ;
+
+: hash-reveal ( nfa wid -- )
+    2dup (reveal) (reveal ;
+
+: inithash ( wid -- )
+    wordlist-extend
+    insRule @ >r  insRule off  hash-alloc 3 cells - dup
+    BEGIN  @ dup  WHILE  2dup swap (reveal  REPEAT
+    2drop  r> insRule ! ;
+
+: addall  ( -- )
+    voclink
+    BEGIN  @ dup WHILE
+	   dup 0 wordlist-link -
+	   dup wordlist-map @ hashsearch-map = 
+	   IF  inithash ELSE drop THEN
+    REPEAT  drop ;
+
+: clearhash  ( -- )
+    HashTable Hashlen cells bounds
+    DO  I @
+	BEGIN  dup  WHILE
+	       dup @ swap HashPointer DelFix
+        REPEAT  I !
+    cell +LOOP  HashIndex off 
+    voclink
+    BEGIN @ dup WHILE
+	  dup 0 wordlist-link -
+	  dup wordlist-map @ hashsearch-map = 
+	  IF 0 swap wordlist-extend ! ELSE drop THEN
+    REPEAT drop ;
+
+: rehashall  ( wid -- ) 
+  drop revealed @ 
+  IF 	clearhash addall revealed off 
+  THEN ;
+
+: (rehash)   ( wid -- )
+  dup wordlist-extend @ 0=
+  IF   inithash
+  ELSE rehashall THEN ;
+
+\ >rom ?!
+align here    ' hash-find A, ' hash-reveal A, ' (rehash) A, ' (rehash) A,
+to hashsearch-map
+
+\ hash allocate and vocabulary initialization          10oct94py
+
+:noname ( hash-alloc ) ( addr -- addr )  
+  HashTable 0= 
+  IF  Hashlen cells reserve-mem TO HashTable
+      HashTable Hashlen cells erase THEN
+  HashIndex @ over !  1 HashIndex +!
+  HashIndex @ Hashlen >=
+  [ e? ec [IF] ]
+  ABORT" no more space in hashtable"
+  [ [ELSE] ]
+  IF  HashTable >r clearhash
+      1 hashbits 1+ dup  to hashbits  lshift  to hashlen
+      r> free >r  0 to HashTable
+      addall r> throw
+  THEN 
+  [ [THEN] ] ; is hash-alloc
 
 \ Hash-Find                                            01jan93py
+e? cross 0= 
+[IF]
+: make-hash
+  hashsearch-map forth-wordlist cell+ !
+  addall ;
+  make-hash \ Baumsuche ist installiert.
+[ELSE]
+  hashsearch-map forth-wordlist cell+ !
+[THEN]
+
+\ for ec version display that vocabulary goes hashed
+
+: hash-cold  ( -- )
+[ e? ec [IF] ] ." Hashing..." [ [THEN] ]
+  HashPointer off  0 TO HashTable  HashIndex off
+  addall
+\  voclink
+\  BEGIN  @ dup WHILE
+\         dup 0 wordlist-link - initvoc
+\  REPEAT  drop 
+[ e? ec [IF] ] ." Done" cr [ [THEN] ] ;
 
-addall          \ Baum aufbauen
-\ Baumsuche ist installiert.
+' hash-cold INIT8 chained
 
 : .words  ( -- )
-  base @ >r hex context @ 3 cells +  HashLen 0
-  DO  cr  i 2 .r ." : " dup @ i cells +
+  base @ >r hex HashTable  Hashlen 0
+  DO  cr  i 2 .r ." : " dup i cells +
       BEGIN  @ dup  WHILE
-             dup cell+ @ .name  REPEAT  drop
+             dup cell+ @ head>string type space  REPEAT  drop
   LOOP  drop r> base ! ;
 
+\ \ this stuff is for evaluating the hash function
+\ : square dup * ;
+
+\ : countwl  ( -- sum sumsq )
+\     \ gives the number of words in the current wordlist
+\     \ and the sum of squares for the sublist lengths
+\     0 0
+\     hashtable Hashlen cells bounds DO
+\        0 i BEGIN
+\            @ dup WHILE
+\            swap 1+ swap
+\        REPEAT
+\        drop
+\        swap over square +
+\        >r + r>
+\        1 cells
+\    +LOOP ;
+
+\ : chisq ( -- n )
+\     \ n should have about the same size as Hashlen
+\     countwl Hashlen 2 pick */ swap - ;