better type propagation for MULTIPLE-VALUE-BIND

[sbcl.git] / src / compiler / ir1opt.lisp

diff --git a/src/compiler/ir1opt.lisp b/src/compiler/ir1opt.lisp
index e07fe5d..8a4d87e 100644 (file)
--- a/src/compiler/ir1opt.lisp
+++ b/src/compiler/ir1opt.lisp
@@ -222,7 +222,7 @@
                                 it (coerce-to-values type)))
                               (t (coerce-to-values type)))))
                dest)))))
-  (lvar-%externally-checkable-type lvar))
+  (or (lvar-%externally-checkable-type lvar) *wild-type*))
 #!-sb-fluid(declaim (inline flush-lvar-externally-checkable-type))
 (defun flush-lvar-externally-checkable-type (lvar)
   (declare (type lvar lvar))
@@ -1752,7 +1752,7 @@
         (loop for var in (lambda-vars fun)
               do (let ((info (lambda-var-arg-info var)))
                    (when (and info (eq :rest (arg-info-kind info)))
-                     (propagate-to-refs var (specifier-type 'list)))))
+                     (propagate-from-sets var (specifier-type 'list)))))
         ;; The normal case.
         (let* ((vars (lambda-vars fun))
                (union (mapcar (lambda (arg var)
@@ -1988,6 +1988,15 @@
         (unlink-node call)
         (when vals
           (reoptimize-lvar (first vals)))
+        ;; Propagate derived types from the VALUES call to its args:
+        ;; transforms can leave the VALUES call with a better type
+        ;; than its args have, so make sure not to throw that away.
+        (let ((types (values-type-types (node-derived-type use))))
+          (dolist (val vals)
+            (when types
+              (let ((type (pop types)))
+                (assert-lvar-type val type '((type-check . 0)))))))
+        ;; Propagate declared types of MV-BIND variables.
         (propagate-to-args use fun)
         (reoptimize-call use))
       t)))
@@ -2098,17 +2107,20 @@
         (unless (eq value-type *empty-type*)
 
           ;; FIXME: Do it in one step.
-          (filter-lvar
-           value
-           (if (cast-single-value-p cast)
-               `(list 'dummy)
-               `(multiple-value-call #'list 'dummy)))
-          (filter-lvar
-           (cast-value cast)
-           ;; FIXME: Derived type.
-           `(%compile-time-type-error 'dummy
-                                      ',(type-specifier atype)
-                                      ',(type-specifier value-type)))
+          (let ((context (cons (node-source-form cast)
+                               (lvar-source (cast-value cast)))))
+            (filter-lvar
+             value
+             (if (cast-single-value-p cast)
+                 `(list 'dummy)
+                 `(multiple-value-call #'list 'dummy)))
+            (filter-lvar
+             (cast-value cast)
+             ;; FIXME: Derived type.
+             `(%compile-time-type-error 'dummy
+                                        ',(type-specifier atype)
+                                        ',(type-specifier value-type)
+                                        ',context)))
           ;; KLUDGE: FILTER-LVAR does not work for non-returning
           ;; functions, so we declare the return type of
           ;; %COMPILE-TIME-TYPE-ERROR to be * and derive the real type