-(defun simple-vector-compare-and-swap (vector index old new)
- #!+(or x86 x86-64)
- (%simple-vector-compare-and-swap vector
- (%check-bound vector (length vector) index)
- old
- new)
- #!-(or x86 x86-64)
- (let ((n-old (svref vector index)))
- (when (eq old n-old)
- (setf (svref vector index) new))
- n-old))
-