diff options
Diffstat (limited to 'lisp/emacs-lisp/cconv.el')
| -rw-r--r-- | lisp/emacs-lisp/cconv.el | 44 |
1 files changed, 29 insertions, 15 deletions
diff --git a/lisp/emacs-lisp/cconv.el b/lisp/emacs-lisp/cconv.el index e12f0a1753b..7b22121db01 100644 --- a/lisp/emacs-lisp/cconv.el +++ b/lisp/emacs-lisp/cconv.el @@ -1,6 +1,6 @@ ;;; cconv.el --- Closure conversion for statically scoped Emacs Lisp. -*- lexical-binding: t -*- -;; Copyright (C) 2011-2021 Free Software Foundation, Inc. +;; Copyright (C) 2011-2022 Free Software Foundation, Inc. ;; Author: Igor Kuzmin <kzuminig@iro.umontreal.ca> ;; Maintainer: emacs-devel@gnu.org @@ -293,17 +293,31 @@ of converted forms." (cconv-convert form env nil)) funcbody)) (if wrappers - (let ((special-forms '())) - ;; Keep special forms at the beginning of the body. - (while (or (and (cdr funcbody) (stringp (car funcbody))) ;docstring. - (memq (car-safe (car funcbody)) - '(interactive declare :documentation))) - (push (pop funcbody) special-forms)) - (let ((body (macroexp-progn funcbody))) + (pcase-let ((`(,decls . ,body) (macroexp-parse-body funcbody))) + (let ((body (macroexp-progn body))) (dolist (wrapper wrappers) (setq body (funcall wrapper body))) - `(,@(nreverse special-forms) ,@(macroexp-unprogn body)))) + `(,@decls ,@(macroexp-unprogn body)))) funcbody))) +(defun cconv--lifted-arg (var env) + "The argument to use for VAR in λ-lifted calls according to ENV. +This is used when VAR is being shadowed; we may still need its value for +such calls." + (let ((mapping (cdr (assq var env)))) + (pcase-exhaustive mapping + (`(internal-get-closed-var . ,_) + ;; The variable is captured. + mapping) + (`(car-safe ,exp) + ;; The variable is mutably captured; skip + ;; the indirection step because the variable is + ;; passed "by reference" to the λ-lifted function. + exp) + (_ + ;; The variable is not captured; use the (shadowed) variable value. + ;; (If the mapping is `(car-safe SYMBOL)', SYMBOL is always VAR. + var)))) + (defun cconv-convert (form env extend) ;; This function actually rewrites the tree. "Return FORM with all its lambdas changed so they are closed. @@ -432,10 +446,11 @@ places where they originally did not directly appear." ;; One of the lambda-lifted vars is shadowed, so add ;; a reference to the outside binding and arrange to use ;; that reference. - (let ((closedsym (make-symbol (format "closed-%s" var)))) + (let ((var-def (cconv--lifted-arg var env)) + (closedsym (make-symbol (format "closed-%s" var)))) (setq new-env (cconv--remap-llv new-env var closedsym)) (setq new-extend (cons closedsym (remq var new-extend))) - (push `(,closedsym ,var) binders-new))) + (push `(,closedsym ,var-def) binders-new))) ;; We push the element after redefined free variables are ;; processed. This is important to avoid the bug when free @@ -453,14 +468,13 @@ places where they originally did not directly appear." ;; before we know that the var will be in `new-extend' (bug#24171). (dolist (binder binders-new) (when (memq (car-safe binder) new-extend) - ;; One of the lambda-lifted vars is shadowed, so add - ;; a reference to the outside binding and arrange to use - ;; that reference. + ;; One of the lambda-lifted vars is shadowed. (let* ((var (car-safe binder)) + (var-def (cconv--lifted-arg var env)) (closedsym (make-symbol (format "closed-%s" var)))) (setq new-env (cconv--remap-llv new-env var closedsym)) (setq new-extend (cons closedsym (remq var new-extend))) - (push `(,closedsym ,var) binders-new))))) + (push `(,closedsym ,var-def) binders-new))))) `(,letsym ,(nreverse binders-new) . ,(mapcar (lambda (form) |