Reworked version of Forth Source debugger (Mark Cave-Ayland)

This patch implements the following Forth words:

   debug <xt> - Mark word for debugging
   debug-off  - Unmark all words for debugging
   resume     - Return from subordinate Forth interpreter

The source debugger also implements the following commands when it has
been activated:

   Up - Unmark current word for debugging, mark parent and continue
   Down - Mark next word for debugging
   Trace - Continue execution until end of word displaying
           debug information
   Rstack - Display contents of the Rstack
   Forth - Launch subordinate Forth interpreter

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

git-svn-id: svn://coreboot.org/openbios/trunk/openbios-devel@611 f158a5a8-5612-0410-a976-696ce0be7e32

forth/bootstrap/interpreter.fs

@@ -12,6 +12,7 @@
 \ 
 
 0 value interactive?
+0 value terminate?
 
 : exit?
   interactive? 0= if
@@ -122,7 +123,8 @@ defer outer-interpreter
     refill 
 
     ['] interpret catch print-status
-  again
+    terminate?
+  until
 ; ['] outer-interpreter (to)
 
 \ 

forth/debugging/firmware.fs

@@ -62,11 +62,16 @@
 
 
 \ 7.5.3.4    Forth source-level debugger
-
+ 
 : debug    ( "old-name< >" -- )
-  ;
-  
-: (debug    ( xt -- )
+  parse-word            \ Look up word CFA in dictionary
+  $find
+  0 = if
+    ." could not locate word for debugging"
+    2drop
+  else
+    (debug
+  then
   ;
   
 : stepping    ( -- )
@@ -76,7 +81,10 @@
   ;
   
 : debug-off    ( -- )
+  (debug-off)
   ;
   
 : resume    ( -- )
+  \ Set interpreter termination flag
+  1 to terminate?
   ;

forth/lib/vocabulary.fs

@@ -62,9 +62,9 @@ create vocabularies #vocs cells allot \ word lists
   \ which new definitions will be placed. 
   cr
   get-order 0 ?do
-    ." wordlist " i (.) type 2e emit space . cr
+    ." wordlist " i (.) type 2e emit space u. cr
   loop
-  cr ." definitions: " current @ . cr
+  cr ." definitions: " current @ u. cr
   ;