-;;;; Converting to a LET has differing significance to various parts of the
-;;;; compiler:
-;;;; -- The body of a LET is spliced in immediately after the corresponding
-;;;; combination node, making the control transfer explicit and allowing
-;;;; LETs to be mashed together into a single block. The value of the LET is
-;;;; delivered directly to the original continuation for the call,
-;;;; eliminating the need to propagate information from the dummy result
-;;;; continuation.
-;;;; -- As far as IR1 optimization is concerned, it is interesting in that
-;;;; there is only one expression that the variable can be bound to, and
-;;;; this is easily substitited for.
-;;;; -- LETs are interesting to environment analysis and to the back end
-;;;; because in most ways a LET can be considered to be "the same function"
-;;;; as its home function.
-;;;; -- LET conversion has dynamic scope implications, since control transfers
-;;;; within the same environment are local. In a local control transfer,
-;;;; cleanup code must be emitted to remove dynamic bindings that are no
-;;;; longer in effect.
-
-;;; Set up the control transfer to the called lambda. We split the call
-;;; block immediately after the call, and link the head of FUN to the call
-;;; block. The successor block after splitting (where we return to) is
-;;; returned.
-;;;
-;;; If the lambda is is a different component than the call, then we call
-;;; JOIN-COMPONENTS. This only happens in block compilation before
-;;; FIND-INITIAL-DFO.
+;;;; Converting to a LET has differing significance to various parts
+;;;; of the compiler:
+;;;; -- The body of a LET is spliced in immediately after the
+;;;; corresponding combination node, making the control transfer
+;;;; explicit and allowing LETs to be mashed together into a single
+;;;; block. The value of the LET is delivered directly to the
+;;;; original continuation for the call,eliminating the need to
+;;;; propagate information from the dummy result continuation.
+;;;; -- As far as IR1 optimization is concerned, it is interesting in
+;;;; that there is only one expression that the variable can be bound
+;;;; to, and this is easily substitited for.
+;;;; -- LETs are interesting to environment analysis and to the back
+;;;; end because in most ways a LET can be considered to be "the
+;;;; same function" as its home function.
+;;;; -- LET conversion has dynamic scope implications, since control
+;;;; transfers within the same environment are local. In a local
+;;;; control transfer, cleanup code must be emitted to remove
+;;;; dynamic bindings that are no longer in effect.
+
+;;; Set up the control transfer to the called lambda. We split the
+;;; call block immediately after the call, and link the head of FUN to
+;;; the call block. The successor block after splitting (where we
+;;; return to) is returned.
+;;;
+;;; If the lambda is is a different component than the call, then we
+;;; call JOIN-COMPONENTS. This only happens in block compilation
+;;; before FIND-INITIAL-DFO.