anchor.diff:  ;;; introduce an immediate value, and NIL if we do not want to
   ;;; introduce an immediate value.
   (defmethod cleavir-generate-ast:convert-constant-to-immediate
  -    (constant (environment environment))
  +    (constant (environment environment) system)
  +  (declare (ignore system))
     (cond ((and (typep constant 'integer)
   	      (<= #.(- (expt 2 30)) constant #.(1- (expt 2 30))))
   	 (* 2 constant))
  
positive.code: ;;; that contains the function.  And we want the function cell to be
  ;;; accessed at load time.
  (defmethod cleavir-generate-ast:convert-global-function
      ((info cleavir-env:global-function-info) (env environment))
    (cleavir-ast:make-car-ast
     (cleavir-ast:make-load-time-value-ast
      `(sicl-global-environment:function-cell
  
negative.code: ;;; it to generate a call to SICL-EXTRINSIC-ENVIRONMENT:SYMBOL-VALUE,
  ;;; passing it the symbol naming the variable and the environment.
  (defmethod cleavir-generate-ast:convert-special-variable
      ((info cleavir-env:special-variable-info) (env environment) system)
    (declare (ignore system))
    (cleavir-ast:make-call-ast
     (cleavir-ast:make-car-ast
      (cleavir-ast:make-load-time-value-ast
  