Re: [RFC] New cpu --- Morpho ms1

Eewwwww!

Imagine if bison or autoconf had encoded in them knowledge of particular
applications that used them.
[The analogy doesn't port 1-1, but the eewww-ness is equivalent.]

Dave Brolley writes:
 > Index: cgen/rtl-c.scm
 > ===================================================================
 > RCS file: /cvs/src/src/cgen/rtl-c.scm,v
 > retrieving revision 1.5
 > diff -c -p -r1.5 rtl-c.scm
 > *** cgen/rtl-c.scm	16 Jul 2003 05:35:47 -0000	1.5
 > --- cgen/rtl-c.scm	15 Jun 2005 20:58:26 -0000
 > ***************
 > *** 1305,1311 ****
 >   			"bad arg to `operand'" object-or-name)))
 >   )
 >   
 > ! (define-fn xop (estate options mode object) object)
 >   
 >   (define-fn local (estate options mode object-or-name)
 >     (cond ((rtx-temp? object-or-name)
 > --- 1305,1327 ----
 >   			"bad arg to `operand'" object-or-name)))
 >   )
 >   
 > ! (define-fn xop (estate options mode object) 
 > !   (let ((delayed (assoc '#:delay (estate-modifiers estate))))
 > !     (if (and delayed
 > ! 	     (equal? APPLICATION 'SID-SIMULATOR)
 > ! 	     (operand? object))
 > ! 	;; if we're looking at an operand inside a (delay ...) rtx, then we
 > ! 	;; are talking about a _delayed_ operand, which is a different
 > ! 	;; beast.  rather than try to work out what context we were
 > ! 	;; constructed within, we just clone the operand instance and set
 > ! 	;; the new one to have a delayed value. the setters and getters
 > ! 	;; will work it out.
 > ! 	(let ((obj (object-copy object))
 > ! 	      (amount (cadr delayed)))
 > ! 	  (op:set-delay! obj amount)
 > ! 	  obj)
 > ! 	;; else return the normal object
 > ! 	object)))
 >   
 >   (define-fn local (estate options mode object-or-name)
 >     (cond ((rtx-temp? object-or-name)
 > ***************
 > *** 1364,1372 ****
 >     (cx:make VOID "; /*clobber*/\n")
 >   )
 >   
 > ! (define-fn delay (estate options mode n rtx)
 > !   (s-sequence (estate-with-modifiers estate '((#:delay))) VOID '() rtx) ; wip!
 > ! )
 >   
 >   ; Gets expanded as a macro.
 >   ;(define-fn annul (estate yes?)
 > --- 1380,1417 ----
 >     (cx:make VOID "; /*clobber*/\n")
 >   )
 >   
 > ! 
 > ! (define-fn delay (estate options mode num-node rtx)
 > !   (case APPLICATION
 > !     ((SID-SIMULATOR)
 > !      (let* ((n (cadddr num-node))
 > ! 	    (old-delay (let ((old (assoc '#:delay (estate-modifiers estate))))
 > ! 			 (if old (cadr old) 0)))
 > ! 	    (new-delay (+ n old-delay)))    
 > !        (begin
 > ! 	 ;; check for proper usage
 > !      	 (if (let* ((hw (case (car rtx) 
 > ! 			  ((operand) (op:type (rtx-operand-obj rtx)))
 > ! 			  ((xop) (op:type (rtx-xop-obj rtx)))
 > ! 			  (else #f))))		    	       
 > ! 	       (not (and hw (or (pc? hw) (memory? hw) (register? hw)))))
 > ! 	     (context-error 
 > ! 	      (estate-context estate) 
 > ! 	      (string-append 
 > ! 	       "(delay ...) rtx applied to wrong type of operand '" (car rtx) "'. should be pc, register or memory")))
 > ! 	 ;; signal an error if we're delayed and not in a "parallel-insns" CPU
 > ! 	 (if (not (with-parallel?)) 
 > ! 	     (context-error 	      
 > ! 	      (estate-context estate) 
 > ! 	      "delayed operand in a non-parallel cpu"))
 > ! 	 ;; update cpu-global pipeline bound
 > ! 	 (cpu-set-max-delay! (current-cpu) (max (cpu-max-delay (current-cpu)) new-delay))      
 > ! 	 ;; pass along new delay to embedded rtx
 > ! 	 (rtx-eval-with-estate rtx mode (estate-with-modifiers estate `((#:delay ,new-delay)))))))
 > ! 
 > !     ;; not in sid-land
 > !     (else (s-sequence (estate-with-modifiers estate '((#:delay))) VOID '() rtx))))
 > !