(defun constant-lvar-p (thing)
(declare (type (or lvar null) thing))
(and (lvar-p thing)
- (let ((use (principal-lvar-use thing)))
- (and (ref-p use) (constant-p (ref-leaf use))))))
+ (or (let ((use (principal-lvar-use thing)))
+ (and (ref-p use) (constant-p (ref-leaf use))))
+ ;; check for EQL types (but not singleton numeric types)
+ (let ((type (lvar-type thing)))
+ (and (member-type-p type)
+ (eql 1 (member-type-size type)))))))
;;; Return the constant value for an LVAR whose only use is a constant
;;; node.
(declaim (ftype (function (lvar) t) lvar-value))
(defun lvar-value (lvar)
- (let ((use (principal-lvar-use lvar)))
- (constant-value (ref-leaf use))))
+ (let ((use (principal-lvar-use lvar))
+ (type (lvar-type lvar))
+ leaf)
+ (cond ((and (ref-p use)
+ (constant-p (setf leaf (ref-leaf use))))
+ (constant-value leaf))
+ ((and (member-type-p type)
+ (eql 1 (member-type-size type)))
+ (first (member-type-members type)))
+ (t
+ (error "~S used on non-constant LVAR ~S" 'lvar-value lvar)))))
\f
;;;; interface for obtaining results of type inference