master a50d5b219f 3/5: Remove compatibility hacks in LAP optimiser

[Mattias Engdegård]

branch: master
commit a50d5b219f81104e3a5928d4917608fcb4db88d2
Author: Mattias Engdegård <mattiase@acm.org>
Commit: Mattias Engdegård <mattiase@acm.org>

    Remove compatibility hacks in LAP optimiser
    
    * lisp/emacs-lisp/byte-opt.el (byte-optimize-lapcode):
    Remove code forcing forward motion after applying certain
    transformations; these were only there to keep output identical across
    refactorings.
---
 lisp/emacs-lisp/byte-opt.el | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/lisp/emacs-lisp/byte-opt.el b/lisp/emacs-lisp/byte-opt.el
index 148b8f60ff..a54f6595b4 100644
--- a/lisp/emacs-lisp/byte-opt.el
+++ b/lisp/emacs-lisp/byte-opt.el
@@ -2145,7 +2145,6 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
              (setq keep-going t)
               (setcdr prev (cdr rest))          ; remove dup
               (setcdr (cdr rest) (cdddr rest))  ; remove discard
-              (setq prev (cdr rest))  ; FIXME: temporary compat hack
               (cond ((not (eq (car lap1) 'byte-stack-set))
                     (byte-compile-log-lap "  %s %s %s\t-->\t%s"
                                            lap0 lap1 lap2 lap1))
@@ -2218,9 +2217,7 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                     (byte-compile-log-lap "  %s %s\t-->\t%s %s"
                                            lap0 lap1
                                            lap0 (cons 'byte-goto (cdr lap1)))
-                    (setcar lap1 'byte-goto)
-                     (setq prev (cdr prev))  ; FIXME: temporary compat hack
-                     ))
+                    (setcar lap1 'byte-goto)))
               (setq keep-going t))
             ;;
             ;; varref-X varref-X  -->  varref-X dup
@@ -2321,7 +2318,6 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                         lap0 i (if (= i 1) "" "s")
                         tagstr lap0 tagstr))))
                (setcdr rest tmp)
-                (setq prev rest)              ; FIXME: temporary compat hack
                (setq keep-going t)))
             ;;
             ;; <safe-op> unbind --> unbind <safe-op>
@@ -2378,7 +2374,6 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                        (when (eq (car tmp) 'byte-return)
                          (setcar lap0 'byte-return))
                        (setcdr lap0 (cdr tmp))
-                        (setq prev (cdr prev))  ; FIXME: temporary compat hack
                        (setq keep-going t)
                         t)))))
 
@@ -2447,7 +2442,6 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                                                (car lap0) tmp2 (nth 1 tmp3))
                          (setcar lap0 (nth 1 tmp3))
                          (setcdr lap0 (nth 1 tmp)))
-                        (setq prev (cdr prev))  ; FIXME: temporary compat hack
                        (setq keep-going t)
                         t)))))
             ;;
@@ -2588,9 +2582,7 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                                   (+ (cdr lap0) (cdr lap1)))))
                 (byte-compile-log-lap "  %s %s\t-->\t%s" lap0 lap1 new-op)
                 (setcar rest new-op)
-                (setcdr rest (cddr rest))
-                (setq prev rest)            ; FIXME: temporary compat hack
-                ))
+                (setcdr rest (cddr rest))))
 
             ;;
             ;; stack-set-M [discard/discardN ...]  -->  discardN-preserve-tos
@@ -2627,7 +2619,7 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                        (setcdr (cdr rest) tmp)
                        (byte-compile-log-lap
                          "  %s [discard/discardN]...\t-->\t%s" lap0 lap1)
-                        ;; FIXME: shouldn't we do (setq keep-going t) here?
+                        (setq keep-going t)
                         t
                         )))))
 
@@ -2694,9 +2686,7 @@ If FOR-EFFECT is non-nil, the return value is assumed to 
be of no importance."
                (byte-compile-log-lap
                 "  %s %s\t-->\t%s %s" lap0 lap1 newdiscard lap0)
                (setf (car rest) newdiscard)
-               (setf (cadr rest) lap0))
-              (setq prev (cdr prev))        ; FIXME: temporary compat hack
-              )
+               (setf (cadr rest) lap0)))
              (t
               ;; If no rule matched, advance and try again.
               (setq prev (cdr prev))))))))