File:  [gforth] / gforth / kernel / cloop2.fs
Revision 1.7: download - view: text, annotated - select for diffs
Mon Dec 31 19:02:25 2007 UTC (14 years, 6 months ago) by anton
Branches: MAIN
CVS tags: v0-7-0, HEAD
updated copyright year after changing license notice

    1: \ Structural Conditionals, loops no extra (?do)		10May99jaw
    2: 
    3: \ Copyright (C) 1995-1997,1999,2000,2003,2007 Free Software Foundation, Inc.
    4: 
    5: \ This file is part of Gforth.
    6: 
    7: \ Gforth is free software; you can redistribute it and/or
    8: \ modify it under the terms of the GNU General Public License
    9: \ as published by the Free Software Foundation, either version 3
   10: \ of the License, or (at your option) any later version.
   11: 
   12: \ This program is distributed in the hope that it will be useful,
   13: \ but WITHOUT ANY WARRANTY; without even the implied warranty of
   14: \ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   15: \ GNU General Public License for more details.
   16: 
   17: \ You should have received a copy of the GNU General Public License
   18: \ along with this program. If not, see http://www.gnu.org/licenses/.
   19: 
   20: [IFDEF] (?do)
   21: 	cr ." Warning: (?do) is defined, use cloop.fs" 
   22: [THEN]
   23: 
   24: Variable tleavings 0 tleavings !
   25: 
   26: : DONE   ( addr -- )
   27:       tleavings @
   28:       BEGIN  dup
   29:       WHILE  >r dup r@ cell+ @ \ address of branch
   30:              u> 0=         \ lower than DO?
   31:       WHILE  r@ 2 cells + @ \ branch token
   32:              branchtoresolve,
   33:              r@ @ r> free throw
   34:       REPEAT drop r>
   35:       THEN
   36:       tleavings ! drop ; immediate restrict
   37: 
   38: : (leave ( branchtoken -- )
   39:     3 cells allocate throw >r
   40:     here r@ cell+ !
   41:     r@ 2 cells + !
   42:     tleavings @ r@ !
   43:     r> tleavings ! ;
   44: 
   45: : LEAVE     branchmark, (leave ;  		immediate restrict
   46: : ?LEAVE    compile 0= ?branchmark, (leave ;	immediate restrict
   47: 
   48: \ Structural Conditionals                              12dec92py
   49: 
   50: \ !!JW ToDo : Move to general tools section
   51: 
   52: : to1 ( x1 x2 xn n -- addr )
   53: \G packs n stack elements in a allocated memory region
   54:    dup dup 1+ cells allocate throw dup >r swap 1+ 0 DO tuck ! cell+ LOOP drop r> ;
   55: : 1to ( addr -- x1 x2 xn )
   56: \G unpacks the elements saved by to1
   57:    dup @ swap over cells + swap 0 DO dup @ swap 1 cells - LOOP free throw ;
   58: 
   59: : loop]     branchto, dup <resolve 1 cells - compile DONE ;
   60: 
   61: : skiploop] ?dup IF compile THEN THEN ;
   62: 
   63: : DO	0 compile (do) branchtomark, 2 to1  ;		immediate restrict
   64: 
   65: : ?DO 	compile 2dup compile = compile IF
   66: 	compile 2drop compile ELSE
   67: 	compile (do) branchtomark, 2 to1 ;		immediate restrict
   68: 
   69: : FOR   compile (for) branchtomark, ;			immediate restrict
   70: 
   71: : LOOP      sys?  1to compile (loop)  loop] compile unloop skiploop] ;     
   72: 							immediate restrict
   73: : +LOOP     sys? 1to compile (+loop)  loop] compile unloop skiploop] ;
   74: 							immediate restrict
   75: : NEXT      sys? compile (next)  loop] compile unloop ;
   76: 							immediate restrict
   77: : EXIT compile ;s ; immediate restrict
   78: : ?EXIT postpone IF postpone EXIT postpone THEN ; immediate restrict

FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>