X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fir1util.lisp;h=ea581fb5e4864d8c56f7455b913a04960cd0142a;hb=784b195743728436795b90f95273c3535ebee9a5;hp=4988282cc8a56abd23719c8f214c7d1da728822f;hpb=25e76ec2b1083ac6a4bba42af7ad7b5a8239f2b8;p=sbcl.git

diff --git a/src/compiler/ir1util.lisp b/src/compiler/ir1util.lisp
index 4988282..ea581fb 100644
--- a/src/compiler/ir1util.lisp
+++ b/src/compiler/ir1util.lisp
@@ -37,22 +37,24 @@
 	   (type (or cleanup null) cleanup))
   (setf (component-reanalyze (block-component block1)) t)
   (with-ir1-environment-from-node node
-    (let* ((start (make-continuation))
-	   (block (continuation-starts-block start))
-	   (cont (make-continuation))
-	   (*lexenv* (if cleanup
-			 (make-lexenv :cleanup cleanup)
-			 *lexenv*)))
-      (change-block-successor block1 block2 block)
-      (link-blocks block block2)
-      (ir1-convert start cont form)
-      (setf (block-last block) (continuation-use cont))
-      block)))
+    (with-component-last-block (*current-component*
+                                (block-next (component-head *current-component*)))
+      (let* ((start (make-continuation))
+             (block (continuation-starts-block start))
+             (cont (make-continuation))
+             (*lexenv* (if cleanup
+                           (make-lexenv :cleanup cleanup)
+                           *lexenv*)))
+        (change-block-successor block1 block2 block)
+        (link-blocks block block2)
+        (ir1-convert start cont form)
+        (setf (block-last block) (continuation-use cont))
+        block))))
 
 ;;;; continuation use hacking
 
 ;;; Return a list of all the nodes which use Cont.
-(declaim (ftype (function (continuation) list) find-uses))
+(declaim (ftype (sfunction (continuation) list) find-uses))
 (defun find-uses (cont)
   (ecase (continuation-kind cont)
     ((:block-start :deleted-block-start)
@@ -61,6 +63,12 @@
     (:unused nil)
     (:deleted nil)))
 
+(defun principal-continuation-use (cont)
+  (let ((use (continuation-use cont)))
+    (if (cast-p use)
+        (principal-continuation-use (cast-value use))
+        use)))
+
 ;;; Update continuation use information so that NODE is no longer a
 ;;; use of its CONT. If the old continuation doesn't start its block,
 ;;; then we don't update the BLOCK-START-USES, since it will be
@@ -69,7 +77,7 @@
 ;;; Note: if you call this function, you may have to do a
 ;;; REOPTIMIZE-CONTINUATION to inform IR1 optimization that something
 ;;; has changed.
-(declaim (ftype (function (node) (values)) delete-continuation-use))
+(declaim (ftype (sfunction (node) (values)) delete-continuation-use))
 (defun delete-continuation-use (node)
   (let* ((cont (node-cont node))
 	 (block (continuation-block cont)))
@@ -95,7 +103,7 @@
 ;;; Note: if you call this function, you may have to do a
 ;;; REOPTIMIZE-CONTINUATION to inform IR1 optimization that something
 ;;; has changed.
-(declaim (ftype (function (node continuation) (values)) add-continuation-use))
+(declaim (ftype (sfunction (node continuation) (values)) add-continuation-use))
 (defun add-continuation-use (node cont)
   (aver (not (node-cont node)))
   (let ((block (continuation-block cont)))
@@ -112,7 +120,10 @@
        (let ((uses (cons node (block-start-uses block))))
 	 (setf (block-start-uses block) uses)
 	 (setf (continuation-use cont)
-	       (if (cdr uses) nil (car uses)))))))
+	       (if (cdr uses) nil (car uses)))
+         (let ((block (node-block node)))
+           (unless (block-last block)
+             (setf (block-last block) node)))))))
   (setf (node-cont node) cont)
   (values))
 
@@ -122,6 +133,8 @@
   (declare (type continuation cont) (type node node))
   (and (eq (node-cont node) cont)
        (not (eq (continuation-kind cont) :deleted))
+       (eq (continuation-dest cont)
+           (continuation-next cont))
        (let ((cblock (continuation-block cont))
 	     (nblock (node-block node)))
 	 (or (eq cblock nblock)
@@ -148,11 +161,13 @@
        (if (eq old (basic-combination-fun dest))
 	   (setf (basic-combination-fun dest) new)
 	   (setf (basic-combination-args dest)
-		 (nsubst new old (basic-combination-args dest))))))
+		 (nsubst new old (basic-combination-args dest)))))
+      (cast (setf (cast-value dest) new))
+      (null))
 
-    (flush-dest old)
+    (when dest (flush-dest old))
     (setf (continuation-dest new) dest)
-    (setf (continuation-%externally-checkable-type new) nil))
+    (flush-continuation-externally-checkable-type new))
   (values))
 
 ;;; Replace all uses of OLD with uses of NEW, where NEW has an
@@ -168,7 +183,7 @@
   (do-uses (node old)
     (delete-continuation-use node)
     (add-continuation-use node new))
-  (dolist (lexenv-use (continuation-lexenv-uses old))
+  (dolist (lexenv-use (continuation-lexenv-uses old)) ; FIXME - APD
     (setf (cadr lexenv-use) new))
 
   (reoptimize-continuation new)
@@ -190,16 +205,16 @@
   (ecase (continuation-kind cont)
     (:unused
      (aver (not (continuation-block cont)))
-     (let* ((head (component-head *current-component*))
-	    (next (block-next head))
-	    (new-block (make-block cont)))
+     (let* ((next (component-last-block *current-component*))
+            (prev (block-prev next))
+            (new-block (make-block cont)))
        (setf (block-next new-block) next
-	     (block-prev new-block) head
-	     (block-prev next) new-block
-	     (block-next head) new-block
-	     (continuation-block cont) new-block
-	     (continuation-use cont) nil
-	     (continuation-kind cont) :block-start)
+             (block-prev new-block) prev
+             (block-prev next) new-block
+             (block-next prev) new-block
+             (continuation-block cont) new-block
+             (continuation-use cont) nil
+             (continuation-kind cont) :block-start)
        new-block))
     (:block-start
      (continuation-block cont))))
@@ -210,7 +225,7 @@
 ;;;    CONT of LAST in its block, then we make it the start of a new
 ;;;    deleted block.
 ;;; -- If the continuation is :INSIDE-BLOCK inside a block, then we
-;;;    split the block using Node-Ends-Block, which makes the
+;;;    split the block using NODE-ENDS-BLOCK, which makes the
 ;;;    continuation be a :BLOCK-START.
 (defun ensure-block-start (cont)
   (declare (type continuation cont))
@@ -230,6 +245,112 @@
 		(node-ends-block (continuation-use cont))))))))
   (values))
 
+;;;;
+
+;;; Filter values of CONT with a destination through FORM, which must
+;;; be an ordinary/mv call. First argument must be 'DUMMY, which will
+;;; be replaced with CONT. In case of an ordinary call the function
+;;; should not have return type NIL.
+;;;
+;;; TODO: remove preconditions.
+(defun filter-continuation (cont form)
+  (declare (type continuation cont) (type list form))
+  (let ((dest (continuation-dest cont)))
+    (declare (type node dest))
+    (with-ir1-environment-from-node dest
+
+      ;; Ensuring that CONT starts a block lets us freely manipulate its uses.
+      (ensure-block-start cont)
+
+      ;; Make a new continuation and move CONT's uses to it.
+      (let ((new-start (make-continuation))
+            (prev (node-prev dest)))
+        (continuation-starts-block new-start)
+        (substitute-continuation-uses new-start cont)
+
+        ;; Make the DEST node start its block so that we can splice in
+        ;; the LAMBDA code.
+        (when (continuation-use prev)
+          (node-ends-block (continuation-use prev)))
+
+        (let* ((prev-block (continuation-block prev))
+               (new-block (continuation-block new-start))
+               (dummy (make-continuation)))
+
+          ;; Splice in the new block before DEST, giving the new block
+          ;; all of DEST's predecessors.
+          (dolist (block (block-pred prev-block))
+            (change-block-successor block prev-block new-block))
+
+          ;; Convert the lambda form, using the new block start as
+          ;; START and a dummy continuation as CONT.
+          (ir1-convert new-start dummy form)
+
+          ;; TODO: Why should this be true? -- WHN 19990601
+          ;;
+          ;; It is somehow related to the precondition of non-NIL
+          ;; return type of the function. -- APD 2003-3-24
+          (aver (eq (continuation-block dummy) new-block))
+
+          ;; KLUDGE: Comments at the head of this function in CMU CL
+          ;; said that somewhere in here we
+          ;;   Set the new block's start and end cleanups to the *start*
+          ;;   cleanup of PREV's block. This overrides the incorrect
+          ;;   default from WITH-IR1-ENVIRONMENT-FROM-NODE.
+          ;; Unfortunately I can't find any code which corresponds to this.
+          ;; Perhaps it was a stale comment? Or perhaps I just don't
+          ;; understand.. -- WHN 19990521
+
+          (let ((node (continuation-use dummy)))
+            (setf (block-last new-block) node)
+            ;; Change the use to a use of CONT. (We need to use the
+            ;; dummy continuation to get the control transfer right,
+            ;; because we want to go to PREV's block, not CONT's.)
+            (delete-continuation-use node)
+            (add-continuation-use node cont))
+          ;; Link the new block to PREV's block.
+          (link-blocks new-block prev-block))
+
+        ;; Replace 'DUMMY with the new continuation. (We can find
+        ;; 'DUMMY because no LET conversion has been done yet.) The
+        ;; [mv-]combination code from the call in the form will be the
+        ;; use of the new check continuation. We substitute for the
+        ;; first argument of this node.
+        (let* ((node (continuation-use cont))
+               (args (basic-combination-args node))
+               (victim (first args)))
+          (aver (eq (constant-value (ref-leaf (continuation-use victim)))
+                    'dummy))
+          (substitute-continuation new-start victim)))
+
+      ;; Invoking local call analysis converts this call to a LET.
+      (locall-analyze-component *current-component*)
+
+      (values))))
+
+;;; Deleting a filter may result in some calls becoming tail.
+(defun delete-filter (node cont value)
+  (collect ((merges))
+    (prog2
+        (when (return-p (continuation-dest cont))
+          (do-uses (use value)
+            (when (and (basic-combination-p use)
+                       (eq (basic-combination-kind use) :local))
+              (merges use))))
+        (cond ((and (eq (continuation-kind cont) :inside-block)
+                    (eq (continuation-kind value) :inside-block))
+               (setf (continuation-dest value) nil)
+               (substitute-continuation value cont)
+               (prog1 (unlink-node node)
+                 (setq cont value)))
+              (t (ensure-block-start value)
+                 (ensure-block-start cont)
+                 (substitute-continuation-uses cont value)
+                 (prog1 (unlink-node node)
+                   (setf (continuation-dest value) nil))))
+      (dolist (merge (merges))
+        (merge-tail-sets merge)))))
+
 ;;;; miscellaneous shorthand functions
 
 ;;; Return the home (i.e. enclosing non-LET) CLAMBDA for NODE. Since
@@ -245,19 +366,20 @@
     (when (eq (lambda-home fun) fun)
       (return fun))))
 
+(declaim (ftype (sfunction (node) cblock) node-block))
 (defun node-block (node)
-  (declare (type node node))
-  (the cblock (continuation-block (node-prev node))))
+  (continuation-block (node-prev node)))
+(declaim (ftype (sfunction (node) component) node-component))
 (defun node-component (node)
-  (declare (type node node))
   (block-component (node-block node)))
+(declaim (ftype (sfunction (node) physenv) node-physenv))
 (defun node-physenv (node)
-  (declare (type node node))
-  (the physenv (lambda-physenv (node-home-lambda node))))
+  (lambda-physenv (node-home-lambda node)))
 
+(declaim (ftype (sfunction (clambda) cblock) lambda-block))
 (defun lambda-block (clambda)
-  (declare (type clambda clambda))
   (node-block (lambda-bind clambda)))
+(declaim (ftype (sfunction (clambda) component) lambda-component))
 (defun lambda-component (clambda)
   (block-component (lambda-block clambda)))
 
@@ -278,8 +400,8 @@
 ;;;   (BLOCK B (RETURN-FROM B) (SETQ X 3))
 ;;; where the block is just a placeholder during parsing and doesn't
 ;;; actually correspond to code which will be written anywhere.
+(declaim (ftype (sfunction (cblock) (or clambda null)) block-home-lambda-or-null))
 (defun block-home-lambda-or-null (block)
-  (declare (type cblock block))
   (if (node-p (block-last block))
       ;; This is the old CMU CL way of doing it.
       (node-home-lambda (block-last block))
@@ -309,13 +431,13 @@
 	    nil))))
 
 ;;; Return the non-LET LAMBDA that holds BLOCK's code.
+(declaim (ftype (sfunction (cblock) clambda) block-home-lambda))
 (defun block-home-lambda (block)
-  (the clambda
-    (block-home-lambda-or-null block)))
+  (block-home-lambda-or-null block))
 
 ;;; Return the IR1 physical environment for BLOCK.
+(declaim (ftype (sfunction (cblock) physenv) block-physenv))
 (defun block-physenv (block)
-  (declare (type cblock block))
   (lambda-physenv (block-home-lambda block)))
 
 ;;; Return the Top Level Form number of PATH, i.e. the ordinal number
@@ -361,6 +483,8 @@
 	(values nil nil))))
 
 ;;; Return the LAMBDA that is CONT's home, or NIL if there is none.
+(declaim (ftype (sfunction (continuation) (or clambda null))
+                continuation-home-lambda-or-null))
 (defun continuation-home-lambda-or-null (cont)
   ;; KLUDGE: This function is a post-CMU-CL hack by WHN, and this
   ;; implementation might not be quite right, or might be uglier than
@@ -379,9 +503,41 @@
 	 (bug "confused about home lambda for ~S"))))
 
 ;;; Return the LAMBDA that is CONT's home.
+(declaim (ftype (sfunction (continuation) clambda)
+                continuation-home-lambda))
 (defun continuation-home-lambda (cont)
-  (the clambda
-    (continuation-home-lambda-or-null cont)))
+  (continuation-home-lambda-or-null cont))
+
+#!-sb-fluid (declaim (inline continuation-single-value-p))
+(defun continuation-single-value-p (cont)
+  (let ((dest (continuation-dest cont)))
+    (typecase dest
+      ((or creturn exit)
+       nil)
+      (mv-combination
+       (eq (basic-combination-fun dest) cont))
+      (cast
+       (locally
+           (declare (notinline continuation-single-value-p))
+         (and (not (values-type-p (cast-asserted-type dest)))
+              (continuation-single-value-p (node-cont dest)))))
+      (t
+       t))))
+
+(defun principal-continuation-end (cont)
+  (loop for prev = cont then (node-cont dest)
+        for dest = (continuation-dest prev)
+        while (cast-p dest)
+        finally (return (values dest prev))))
+
+(defun principal-continuation-single-valuify (cont)
+  (loop for prev = cont then (node-cont dest)
+     for dest = (continuation-dest prev)
+     while (cast-p dest)
+     do (setf (node-derived-type dest)
+              (make-short-values-type (list (single-value-type
+                                             (node-derived-type dest)))))
+     (reoptimize-continuation prev)))
 
 ;;; Return a new LEXENV just like DEFAULT except for the specified
 ;;; slot values. Values for the alist slots are NCONCed to the
@@ -470,7 +626,7 @@
 
   (let ((new-pred (delq block1 (block-pred block2))))
     (setf (block-pred block2) new-pred)
-    (when (and new-pred (null (rest new-pred)))
+    (when (singleton-p new-pred)
       (let ((pred-block (first new-pred)))
 	(when (if-p (block-last pred-block))
 	  (setf (block-test-modified pred-block) t)))))
@@ -513,7 +669,7 @@
 
 ;;; Unlink a block from the next/prev chain. We also null out the
 ;;; COMPONENT.
-(declaim (ftype (function (cblock) (values)) remove-from-dfo))
+(declaim (ftype (sfunction (cblock) (values)) remove-from-dfo))
 (defun remove-from-dfo (block)
   (let ((next (block-next block))
 	(prev (block-prev block)))
@@ -538,7 +694,7 @@
 
 ;;; Set the FLAG for all the blocks in COMPONENT to NIL, except for
 ;;; the head and tail which are set to T.
-(declaim (ftype (function (component) (values)) clear-flags))
+(declaim (ftype (sfunction (component) (values)) clear-flags))
 (defun clear-flags (component)
   (let ((head (component-head component))
 	(tail (component-tail component)))
@@ -550,11 +706,11 @@
 
 ;;; Make a component with no blocks in it. The BLOCK-FLAG is initially
 ;;; true in the head and tail blocks.
-(declaim (ftype (function nil component) make-empty-component))
+(declaim (ftype (sfunction () component) make-empty-component))
 (defun make-empty-component ()
   (let* ((head (make-block-key :start nil :component nil))
 	 (tail (make-block-key :start nil :component nil))
-	 (res (make-component :head head :tail tail)))
+	 (res (make-component head tail)))
     (setf (block-flag head) t)
     (setf (block-flag tail) t)
     (setf (block-component head) res)
@@ -635,7 +791,7 @@
 
   (values))
 
-;;; Note that something interesting has happened to VAR. 
+;;; Note that something interesting has happened to VAR.
 (defun reoptimize-lambda-var (var)
   (declare (type lambda-var var))
   (let ((fun (lambda-var-home var)))
@@ -706,8 +862,8 @@
                (return-block (and return (node-block return))))
 	  (unless (leaf-ever-used clambda)
 	    (let ((*compiler-error-context* bind))
-	      (compiler-note "deleting unused function~:[.~;~:*~%  ~S~]"
-			     (leaf-debug-name clambda))))
+	      (compiler-notify "deleting unused function~:[.~;~:*~%  ~S~]"
+			       (leaf-debug-name clambda))))
           (unless (block-delete-p bind-block)
             (unlink-blocks (component-head component) bind-block))
 	  (when (and return-block (not (block-delete-p return-block)))
@@ -769,9 +925,10 @@
 			      (maybe-convert-to-assignment fun)))
 			 (t
 			  (maybe-convert-to-assignment fun)))))))
-	
+
 	(dolist (ep (optional-dispatch-entry-points leaf))
-	  (frob ep))
+          (when (promise-ready-p ep)
+            (frob (force ep))))
 	(when (optional-dispatch-more-entry leaf)
 	  (frob (optional-dispatch-more-entry leaf)))
 	(let ((main (optional-dispatch-main-entry leaf)))
@@ -832,7 +989,7 @@
   (unless (eq (continuation-kind cont) :deleted)
     (aver (continuation-dest cont))
     (setf (continuation-dest cont) nil)
-    (setf (continuation-%externally-checkable-type cont) nil)
+    (flush-continuation-externally-checkable-type cont)
     (do-uses (use cont)
       (let ((prev (node-prev use)))
 	(unless (eq (continuation-kind prev) :deleted)
@@ -841,10 +998,18 @@
 	    (setf (block-attributep (block-flags block) flush-p type-asserted)
 		  t))))))
 
-  (setf (continuation-%type-check cont) nil)
-
   (values))
 
+(defun delete-dest (cont)
+  (let ((dest (continuation-dest cont)))
+    (when dest
+      (let ((prev (node-prev dest)))
+	(when (and prev
+		   (not (eq (continuation-kind prev) :deleted)))
+	  (let ((block (continuation-block prev)))
+	    (unless (block-delete-p block)
+	      (mark-for-deletion block))))))))
+
 ;;; Do a graph walk backward from BLOCK, marking all predecessor
 ;;; blocks with the DELETE-P flag.
 (defun mark-for-deletion (block)
@@ -883,26 +1048,16 @@
 	  (setf (block-attributep (block-flags block) flush-p type-asserted) t)
 	  (setf (component-reoptimize (block-component block)) t)))))
 
-  (let ((dest (continuation-dest cont)))
-    (when dest
-      (let ((prev (node-prev dest)))
-	(when (and prev
-		   (not (eq (continuation-kind prev) :deleted)))
-	  (let ((block (continuation-block prev)))
-	    (unless (block-delete-p block)
-	      (mark-for-deletion block)))))))
+  (delete-dest cont)
 
   (setf (continuation-kind cont) :deleted)
   (setf (continuation-dest cont) nil)
-  (setf (continuation-%externally-checkable-type cont) nil)
+  (flush-continuation-externally-checkable-type cont)
   (setf (continuation-next cont) nil)
-  (setf (continuation-asserted-type cont) *empty-type*)
   (setf (continuation-%derived-type cont) *empty-type*)
-  (setf (continuation-type-to-check cont) *empty-type*)
   (setf (continuation-use cont) nil)
   (setf (continuation-block cont) nil)
   (setf (continuation-reoptimize cont) nil)
-  (setf (continuation-%type-check cont) nil)
   (setf (continuation-info cont) nil)
 
   (values))
@@ -915,18 +1070,23 @@
 ;;; We mark the START as has having no next and remove the last node
 ;;; from its CONT's uses. We also flush the DEST for all continuations
 ;;; whose values are received by nodes in the block.
-(defun delete-block (block)
+(defun delete-block (block &optional silent)
   (declare (type cblock block))
-  (aver (block-component block)) ; else block is already deleted!
-  (note-block-deletion block)
+  (aver (block-component block))      ; else block is already deleted!
+  (unless silent
+    (note-block-deletion block))
   (setf (block-delete-p block) t)
 
-  (let* ((last (block-last block))
-	 (cont (node-cont last)))
-    (delete-continuation-use last)
-    (if (eq (continuation-kind cont) :unused)
-	(delete-continuation cont)
-	(reoptimize-continuation cont)))
+  (let ((last (block-last block)))
+    (when last
+      (let ((cont (node-cont last)))
+        (delete-continuation-use last)
+        (acond ((eq (continuation-kind cont) :unused)
+                (delete-continuation cont))
+               ((and (null (find-uses cont))
+                     (continuation-dest cont))
+                (mark-for-deletion (node-block it)))
+               ((reoptimize-continuation cont))))))
 
   (dolist (b (block-pred block))
     (unlink-blocks b block)
@@ -940,7 +1100,7 @@
   (dolist (b (block-succ block))
     (unlink-blocks block b))
 
-  (do-nodes (node cont block)
+  (do-nodes-carefully (node cont block)
     (typecase node
       (ref (delete-ref node))
       (cif
@@ -951,51 +1111,56 @@
       ;; careful that this LET has not already been partially deleted.
       (basic-combination
        (when (and (eq (basic-combination-kind node) :local)
-		  ;; Guards COMBINATION-LAMBDA agains the REF being deleted.
-		  (continuation-use (basic-combination-fun node)))
-	 (let ((fun (combination-lambda node)))
-	   ;; If our REF was the second-to-last ref, and has been
-	   ;; deleted, then FUN may be a LET for some other
-	   ;; combination.
-	   (when (and (functional-letlike-p fun)
-		      (eq (let-combination fun) node))
-	     (delete-lambda fun))))
+                  ;; Guards COMBINATION-LAMBDA agains the REF being deleted.
+                  (continuation-use (basic-combination-fun node)))
+         (let ((fun (combination-lambda node)))
+           ;; If our REF was the second-to-last ref, and has been
+           ;; deleted, then FUN may be a LET for some other
+           ;; combination.
+           (when (and (functional-letlike-p fun)
+                      (eq (let-combination fun) node))
+             (delete-lambda fun))))
        (flush-dest (basic-combination-fun node))
        (dolist (arg (basic-combination-args node))
-	 (when arg (flush-dest arg))))
+         (when arg (flush-dest arg))))
       (bind
        (let ((lambda (bind-lambda node)))
-	 (unless (eq (functional-kind lambda) :deleted)
-	   (delete-lambda lambda))))
+         (unless (eq (functional-kind lambda) :deleted)
+           (delete-lambda lambda))))
       (exit
        (let ((value (exit-value node))
-	     (entry (exit-entry node)))
-	 (when value
-	   (flush-dest value))
-	 (when entry
-	   (setf (entry-exits entry)
-		 (delete node (entry-exits entry))))))
+             (entry (exit-entry node)))
+         (when value
+           (flush-dest value))
+         (when entry
+           (setf (entry-exits entry)
+                 (delete node (entry-exits entry))))))
       (creturn
        (flush-dest (return-result node))
        (delete-return node))
       (cset
        (flush-dest (set-value node))
        (let ((var (set-var node)))
-	 (setf (basic-var-sets var)
-	       (delete node (basic-var-sets var))))))
+         (setf (basic-var-sets var)
+               (delete node (basic-var-sets var)))))
+      (cast
+       (flush-dest (cast-value node))))
 
     (delete-continuation (node-prev node)))
 
   (remove-from-dfo block)
   (values))
 
-;;; Do stuff to indicate that the return node Node is being deleted.
-;;; We set the RETURN to NIL.
+;;; Do stuff to indicate that the return node NODE is being deleted.
 (defun delete-return (node)
   (declare (type creturn node))
-  (let ((fun (return-lambda node)))
+  (let* ((fun (return-lambda node))
+         (tail-set (lambda-tail-set fun)))
     (aver (lambda-return fun))
-    (setf (lambda-return fun) nil))
+    (setf (lambda-return fun) nil)
+    (when (and tail-set (not (find-if #'lambda-return
+                                      (tail-set-funs tail-set))))
+      (setf (tail-set-type tail-set) *empty-type*)))
   (values))
 
 ;;; If any of the VARS in FUN was never referenced and was not
@@ -1080,7 +1245,7 @@
 					  0)))
 	    (unless (return-p node)
 	      (let ((*compiler-error-context* node))
-		(compiler-note "deleting unreachable code")))
+		(compiler-notify "deleting unreachable code")))
 	    (return))))))
   (values))
 
@@ -1125,7 +1290,10 @@
 		  (setf (continuation-next prev) nil))
 		 (t
 		  (setf (continuation-next prev) next)
-		  (setf (node-prev next) prev)))
+		  (setf (node-prev next) prev)
+                  (when (and (if-p next) ; AOP wanted
+                             (eq prev (if-test next)))
+                    (reoptimize-continuation prev))))
 	   (setf (node-prev node) nil)
 	   nil)
 	  (t
@@ -1133,7 +1301,7 @@
 	   (aver (eq node last))
 	   (let* ((succ (block-succ block))
 		  (next (first succ)))
-	     (aver (and succ (null (cdr succ))))
+	     (aver (singleton-p succ))
 	     (cond
 	      ((member block succ)
 	       (with-ir1-environment-from-node node
@@ -1224,18 +1392,26 @@
 	       (after-args (subseq outside-args (1+ arg-position))))
 	  (dolist (arg inside-args)
 	    (setf (continuation-dest arg) outside)
-            (setf (continuation-%externally-checkable-type arg) nil))
+            (flush-continuation-externally-checkable-type arg))
 	  (setf (combination-args inside) nil)
 	  (setf (combination-args outside)
 		(append before-args inside-args after-args))
 	  (change-ref-leaf (continuation-use inside-fun)
 			   (find-free-fun 'list "???"))
-	  (setf (combination-kind inside) :full)
+	  (setf (combination-kind inside)
+                (info :function :info 'list))
 	  (setf (node-derived-type inside) *wild-type*)
 	  (flush-dest cont)
-	  (setf (continuation-asserted-type cont) *wild-type*)
-          (setf (continuation-type-to-check cont) *wild-type*)
 	  (values))))))
+
+(defun flush-combination (combination)
+  (declare (type combination combination))
+  (flush-dest (combination-fun combination))
+  (dolist (arg (combination-args combination))
+    (flush-dest arg))
+  (unlink-node combination)
+  (values))
+
 
 ;;;; leaf hackery
 
@@ -1247,10 +1423,15 @@
     (delete-ref ref)
     (setf (ref-leaf ref) leaf)
     (setf (leaf-ever-used leaf) t)
-    (let ((ltype (leaf-type leaf)))
-      (if (fun-type-p ltype)
-	  (setf (node-derived-type ref) ltype)
-	  (derive-node-type ref ltype)))
+    (let* ((ltype (leaf-type leaf))
+           (vltype (make-single-value-type ltype)))
+      (if (let* ((cont (node-cont ref))
+                 (dest (continuation-dest cont)))
+            (and (basic-combination-p dest)
+                 (eq cont (basic-combination-fun dest))
+                 (csubtypep ltype (specifier-type 'function))))
+	  (setf (node-derived-type ref) vltype)
+	  (derive-node-type ref vltype)))
     (reoptimize-continuation (node-cont ref)))
   (values))
 
@@ -1289,6 +1470,21 @@
 		     :type (ctype-of object)
 		     :where-from :defined)))
 
+;;; Return true if VAR would have to be closed over if environment
+;;; analysis ran now (i.e. if there are any uses that have a different
+;;; home lambda than VAR's home.)
+(defun closure-var-p (var)
+  (declare (type lambda-var var))
+  (let ((home (lambda-var-home var)))
+    (cond ((eq (functional-kind home) :deleted)
+           nil)
+          (t (let ((home (lambda-home home)))
+               (flet ((frob (l)
+                        (find home l :key #'node-home-lambda
+                              :test-not #'eq)))
+                 (or (frob (leaf-refs var))
+                     (frob (basic-var-sets var)))))))))
+
 ;;; If there is a non-local exit noted in ENTRY's environment that
 ;;; exits to CONT in that entry, then return it, otherwise return NIL.
 (defun find-nlx-info (entry cont)
@@ -1301,7 +1497,7 @@
 
 ;;;; functional hackery
 
-(declaim (ftype (function (functional) clambda) main-entry))
+(declaim (ftype (sfunction (functional) clambda) main-entry))
 (defun main-entry (functional)
   (etypecase functional
     (clambda functional)
@@ -1312,7 +1508,7 @@
 ;;; MV-BIND when it appears in an MV-CALL. All fixed arguments must be
 ;;; optional with null default and no SUPPLIED-P. There must be a
 ;;; &REST arg with no references.
-(declaim (ftype (function (functional) boolean) looks-like-an-mv-bind))
+(declaim (ftype (sfunction (functional) boolean) looks-like-an-mv-bind))
 (defun looks-like-an-mv-bind (functional)
   (and (optional-dispatch-p functional)
        (do ((arg (optional-dispatch-arglist functional) (cdr arg)))
@@ -1403,12 +1599,26 @@
 	   ;; compiler to be able to use WITH-COMPILATION-UNIT on
 	   ;; arbitrarily huge blocks of code. -- WHN)
 	   (let ((*compiler-error-context* node))
-	     (compiler-note "*INLINE-EXPANSION-LIMIT* (~W) was exceeded, ~
-			     probably trying to~%  ~
-			     inline a recursive function."
-			    *inline-expansion-limit*))
+	     (compiler-notify "*INLINE-EXPANSION-LIMIT* (~W) was exceeded, ~
+			       probably trying to~%  ~
+			       inline a recursive function."
+			      *inline-expansion-limit*))
 	   nil)
 	  (t t))))
+
+;;; Make sure that FUNCTIONAL is not let-converted or deleted.
+(defun assure-functional-live-p (functional)
+  (declare (type functional functional))
+  (when (and (or
+              ;; looks LET-converted
+              (functional-somewhat-letlike-p functional)
+              ;; It's possible for a LET-converted function to end up
+              ;; deleted later. In that case, for the purposes of this
+              ;; analysis, it is LET-converted: LET-converted functionals
+              ;; are too badly trashed to expand them inline, and deleted
+              ;; LET-converted functionals are even worse.
+              (eql (functional-kind functional) :deleted)))
+    (throw 'locall-already-let-converted functional)))
 
 ;;;; careful call
 
@@ -1418,7 +1628,7 @@
 ;;; return NIL as our second value to indicate this. NODE is used as
 ;;; the error context for any error message, and CONTEXT is a string
 ;;; that is spliced into the warning.
-(declaim (ftype (function ((or symbol function) list node function string)
+(declaim (ftype (sfunction ((or symbol function) list node function string)
 			  (values list boolean))
 		careful-call))
 (defun careful-call (function args node warn-fun context)
@@ -1438,6 +1648,8 @@
        `(progn
           (defun ,careful (specifier)
             (handler-case (,basic specifier)
+	      (sb!kernel::arg-count-error (condition)
+		(values nil (list (format nil "~A" condition))))
               (simple-error (condition)
                 (values nil (list* (simple-condition-format-control condition)
                                    (simple-condition-format-arguments condition))))))
@@ -1461,7 +1673,7 @@
 ;;; list of continuations ARGS. It returns the continuation if the
 ;;; keyword is present, or NIL otherwise. The legality and
 ;;; constantness of the keywords should already have been checked.
-(declaim (ftype (function (list keyword) (or continuation null))
+(declaim (ftype (sfunction (list keyword) (or continuation null))
 		find-keyword-continuation))
 (defun find-keyword-continuation (args key)
   (do ((arg args (cddr arg)))
@@ -1472,7 +1684,7 @@
 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
 ;;; verify that alternating continuations in ARGS are constant and
 ;;; that there is an even number of args.
-(declaim (ftype (function (list) boolean) check-key-args-constant))
+(declaim (ftype (sfunction (list) boolean) check-key-args-constant))
 (defun check-key-args-constant (args)
   (do ((arg args (cddr arg)))
       ((null arg) t)
@@ -1484,7 +1696,7 @@
 ;;; verify that the list of continuations ARGS is a well-formed &KEY
 ;;; arglist and that only keywords present in the list KEYS are
 ;;; supplied.
-(declaim (ftype (function (list list) boolean) check-transform-keys))
+(declaim (ftype (sfunction (list list) boolean) check-transform-keys))
 (defun check-transform-keys (args keys)
   (and (check-key-args-constant args)
        (do ((arg args (cddr arg)))
@@ -1495,19 +1707,44 @@
 ;;;; miscellaneous
 
 ;;; Called by the expansion of the EVENT macro.
-(declaim (ftype (function (event-info (or node null)) *) %event))
+(declaim (ftype (sfunction (event-info (or node null)) *) %event))
 (defun %event (info node)
   (incf (event-info-count info))
   (when (and (>= (event-info-level info) *event-note-threshold*)
 	     (policy (or node *lexenv*)
 		     (= inhibit-warnings 0)))
     (let ((*compiler-error-context* node))
-      (compiler-note (event-info-description info))))
+      (compiler-notify (event-info-description info))))
 
   (let ((action (event-info-action info)))
     (when action (funcall action node))))
 
-;;; It should be in locall.lisp, but is used before in ir1opt.lisp.
-(define-optimization-quality verify-arg-count
-    (if (zerop safety) 0 3)
-  ("no" "maybe" "yes" "yes"))
+;;;
+(defun make-cast (value type policy)
+  (declare (type continuation value)
+           (type ctype type)
+           (type policy policy))
+  (%make-cast :asserted-type type
+              :type-to-check (maybe-weaken-check type policy)
+              :value value
+              :derived-type (coerce-to-values type)))
+
+(defun cast-type-check (cast)
+  (declare (type cast cast))
+  (when (cast-reoptimize cast)
+    (ir1-optimize-cast cast t))
+  (cast-%type-check cast))
+
+(defun note-single-valuified-continuation (cont)
+  (declare (type continuation cont))
+  (let ((use (continuation-use cont)))
+    (cond ((ref-p use)
+           (let ((leaf (ref-leaf use)))
+             (when (and (lambda-var-p leaf)
+                        (null (rest (leaf-refs leaf))))
+               (reoptimize-lambda-var leaf))))
+          ((or (null use) (combination-p use))
+           (dolist (node (find-uses cont))
+             (setf (node-reoptimize node) t)
+             (setf (block-reoptimize (node-block node)) t)
+             (setf (component-reoptimize (node-component node)) t))))))