From: Andrea Corallo <akrl@sdf.org>
Date: Mon, 25 Nov 2019 20:27:11 +0000 (+0100)
Subject: fix comp-propagate-insn type propagation
X-Git-Tag: emacs-28.0.90~2727^2~936
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=a214a29e48397cf259327e1ffb44479648301e47;p=emacs.git

fix comp-propagate-insn type propagation
---

diff --git a/lisp/emacs-lisp/comp.el b/lisp/emacs-lisp/comp.el
index 4167dcf4b91..2ac912929d1 100644
--- a/lisp/emacs-lisp/comp.el
+++ b/lisp/emacs-lisp/comp.el
@@ -1553,14 +1553,19 @@ This can run just once."
         (comp-mvar-propagate lval rval))))
     (`(phi ,lval . ,rest)
      ;; Const prop here.
-     (when (and (cl-every #'comp-mvar-const-vld rest)
-                (cl-reduce #'equal (mapcar #'comp-mvar-constant rest)))
-       (setf (comp-mvar-constant lval) (comp-mvar-constant (car rest))))
+     (when-let* ((vld (cl-every #'comp-mvar-const-vld rest))
+                 (consts (mapcar #'comp-mvar-constant rest))
+                 (x (car consts))
+                 (equals (cl-every (lambda (y) (equal x y)) consts)))
+       (setf (comp-mvar-constant lval) x))
      ;; Type propagation.
      ;; FIXME: checking for type equality is not sufficient cause does not
-     ;; account type hierarchy!!
-     (when (cl-reduce #'eq (mapcar #'comp-mvar-type rest))
-       (setf (comp-mvar-type lval) (comp-mvar-type (car rest))))
+     ;; account type hierarchy!
+     (when-let* ((types (mapcar #'comp-mvar-type rest))
+                 (non-empty (cl-notany #'null types))
+                 (x (car types))
+                 (eqs (cl-every (lambda (y) (eq x y)) types)))
+       (setf (comp-mvar-type lval) x))
      ;; Reference propagation.
      (let ((operands (cons lval rest)))
        (when (cl-some #'comp-mvar-ref operands)