[Patch] Emit error for undefined operands

[Ben Elliston <bje at redhat dot com>]

>>>>> "Ben" == Ben Elliston <bje@redhat.com> writes:

  Ben> Here is another patch (precariously close to the last one!) which
  Ben> emits a parse error for undefined operands which appear in the syntax
  Ben> string.  Okay to commit?

Please disregard the last message on this subject.  Here's a much
cleaner version that utilises the function (current-op-lookup).  Okay?


2001-03-21  Ben Elliston  <bje@redhat.com>

	* opc-itab.scm (compute-syntax): Emit a parse error if an operand
	given in a syntax string is undefined.

Index: opc-itab.scm
===================================================================
RCS file: /cvs/cvsfiles/devo/cgen/opc-itab.scm,v
retrieving revision 1.21
diff -u -c -r1.21 opc-itab.scm
*** opc-itab.scm	2001/03/20 19:49:10	1.21
--- opc-itab.scm	2001/03/21 07:09:42
***************
*** 162,167 ****
--- 162,172 ----
  						  (substring syn 2 n)))
  						"), ")))))
  		 (let ((n (id-len (string-drop1 syn))))
 		   (if (= n 0)
 		       (parse-error context "empty or invalid operand name" syntax))
+ 		   (let ((operand (string->symbol (substring syn 1 (1+ n)))))
+ 		     (if (not (current-op-lookup operand))
+ 			 (parse-error context "undefined operand " operand syntax)))
  		   (loop (string-drop (1+ n) syn)
  			 (string-append result op-macro " ("
  					(string-upcase