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Define compiler macros for /=, atom and nlistp

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Calls to these functions were previously rewritten in terms of other
functions both in the optimiser and during codegen, for no good reason.

This also resulted in poor diagnostics: wrong-arity calls to 'atom' and
'nlistp' produced doubled but slightly-different warnings, and no
warnings at all for '/='.

Using compiler macros fixes the problems.  The generated code is the same.

* lisp/emacs-lisp/bytecomp.el (byte-compile-negated)
(byte-compile-negation-optimizer): Replace with...
(bytecomp--define-negated): ...this compiler macro defining macro.
This commit is contained in:
Mattias Engdegård 2025-10-29 13:02:32 +01:00
parent 85e1a64943
commit 305744fdfc
2 changed files with 12 additions and 28 deletions
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6
lisp/emacs-lisp/byte-opt.el
View file

@ -1424,12 +1424,6 @@ See Info node `(elisp) Integer Basics'."
(put 'not 'byte-optimizer #'byte-optimize-not)
(put 'null 'byte-optimizer #'byte-optimize-not)
;; byte-compile-negation-optimizer lives in bytecomp.el
(put '/= 'byte-optimizer #'byte-compile-negation-optimizer)
(put 'atom 'byte-optimizer #'byte-compile-negation-optimizer)
(put 'nlistp 'byte-optimizer #'byte-compile-negation-optimizer)
(defun byte-optimize-funcall (form)
;; (funcall #'(lambda ...) ...) -> (let ...)
;; (funcall #'SYM ...) -> (SYM ...)

34
lisp/emacs-lisp/bytecomp.el
View file

@ -4911,28 +4911,6 @@ binding slots have been popped."
(> byte-compile-depth init-stack-depth))))))
(byte-defop-compiler-1 /= byte-compile-negated)
(byte-defop-compiler-1 atom byte-compile-negated)
(byte-defop-compiler-1 nlistp byte-compile-negated)
(put '/= 'byte-compile-negated-op '=)
(put 'atom 'byte-compile-negated-op 'consp)
(put 'nlistp 'byte-compile-negated-op 'listp)
(defun byte-compile-negated (form)
(byte-compile-form-do-effect (byte-compile-negation-optimizer form)))
;; Even when optimization is off, /= is optimized to (not (= ...)).
(defun byte-compile-negation-optimizer (form)
;; an optimizer for forms where <form1> is less efficient than (not <form2>)
(list 'not
(cons (or (get (car form) 'byte-compile-negated-op)
(error
"Compiler error: `%s' has no `byte-compile-negated-op' property"
(car form)))
(cdr form))))
;;; other tricky macro-like special-forms
(byte-defop-compiler-1 catch)
@ -5883,6 +5861,18 @@ and corresponding effects."
(featurep (cadr feature))
form)))
(defmacro bytecomp--define-negated (fn arity negfn)
"Define FN with ARITY as the Boolean negation of NEGFN."
`(put ',fn 'compiler-macro
(lambda (form &rest args)
(if (= (length args) ,arity)
(list 'not (cons ',negfn args))
form))))
(bytecomp--define-negated /= 2 = )
(bytecomp--define-negated atom 1 consp)
(bytecomp--define-negated nlistp 1 listp)
;; Report comma operator used outside of backquote.
;; Inside backquote, backquote will transform it before it gets here.