--- gforth/code.fs	1999/12/03 18:24:21	1.9
+++ gforth/code.fs	2010/12/31 18:09:02	1.23
@@ -1,12 +1,12 @@
 \ ASSEMBLER, CODE etc.
 
-\ Copyright (C) 1995,1996,1997 Free Software Foundation, Inc.
+\ Copyright (C) 1995,1996,1997,1999,2003,2007,2010 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
+\ as published by the Free Software Foundation, either version 3
 \ of the License, or (at your option) any later version.
 
 \ This program is distributed in the hope that it will be useful,
@@ -15,42 +15,75 @@
 \ 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.
+\ along with this program. If not, see http://www.gnu.org/licenses/.
 
 \ does not include the actual assembler (which is machine-dependent),
 \ only words like CODE that are implementation-dependent, but can be
 \ defined for all machines.
 
 vocabulary assembler ( -- ) \ tools-ext
+\g A vocubulary: Replaces the wordlist at the top of the search order
+\g with the assembler wordlist.
 
 : init-asm ( -- ) \ gforth
+\g Pushes the assembler wordlist on the search order.
     also assembler ;
-
+    
 : code ( "name" -- colon-sys )	\ tools-ext
-    \ start a native code definition
+    \G Start a native code definition that runs in the context of the
+    \G Gforth virtual machine (engine).  Such a definition is not
+    \G portable between Gforth installations, so we recommend using
+    \G @code{abi-code} instead of @code{code}.  You have to end a
+    \G @code{code} definition with a dispatch to the next virtual
+    \G machine instruction.
     header
-    threading-method
-    if
-	here >body cfa,
-    then
+    here >body cfa,
+    defstart init-asm ;
+
+[ifdef] doabicode:
+: abi-code ( "name" -- colon-sys )	\ gforth	abi-code
+   \G Start a native code definition that is called using the platform's
+   \G ABI conventions corresponding to the C-prototype:
+   \G @example
+   \G Cell *function(Cell *sp, Float **fpp);
+   \G @end example
+   \G The FP stack pointer is passed in by providing a reference to a
+   \G memory location containing the FP stack pointer and is passed
+   \G out by storing the changed FP stack pointer there (if necessary).
+    header  
+    doabicode: cfa,
     defstart init-asm ;
+[endif]
 
 : (;code) ( -- ) \ gforth
     \ execution semantics of @code{;code}
-    r> lastxt code-address! ;
+    r> latestxt code-address! ;
 
 :noname ( -- colon-sys )
-    align here lastxt code-address!
+    align here latestxt code-address!
     defstart init-asm ;
 :noname ( colon-sys1 -- colon-sys2 )	\ tools-ext	semicolon-code
     ( create the [;code] part of a low level defining word )
-    ;-hook postpone (;code) ?struc postpone [
+    ;-hook postpone (;code) basic-block-end finish-code ?struc postpone [
     defstart init-asm ;
 interpret/compile: ;code ( compilation. colon-sys1 -- colon-sys2 )	\ tools-ext	semicolon-code
-
+\g The code after @code{;code} becomes the behaviour of the last
+\g defined word (which must be a @code{create}d word).  The same
+\g caveats apply as for @code{code}, so we recommend using
+\g @code{;abi-code} instead.
+
+[ifdef] do;abicode: 
+: !;abi-code ( addr -- )
+    latestxt do;abicode: any-code! ;
+
+: ;abi-code ( -- ) \ gforth semicolon-abi-code
+    ['] !;abi-code does>-like postpone [ init-asm ; immediate
+[then]
+    
 : end-code ( colon-sys -- )	\ gforth	end_code
-    ( end a code definition )
-    lastxt here over - flush-icache
+    \G End a code definition.  Note that you have to assemble the
+    \G return from the ABI call (for @code{abi-code}) or the dispatch
+    \G to the next VM instruction (for @code{code} and @code{;code})
+    \G yourself.
+    latestxt here over - flush-icache
     previous ?struc reveal ;
-