; Spelling, punctuation and minor wording fixes

[emacs.git] / lisp / emacs-lisp / bytecomp.el

;;; bytecomp.el --- compilation of Lisp code into byte code -*- lexical-binding: t -*-

;; Copyright (C) 1985-1987, 1992, 1994, 1998, 2000-2017 Free Software
;; Foundation, Inc.

;; Author: Jamie Zawinski <jwz@lucid.com>
;;      Hallvard Furuseth <hbf@ulrik.uio.no>
;; Maintainer: emacs-devel@gnu.org
;; Keywords: lisp
;; Package: emacs

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; The Emacs Lisp byte compiler.  This crunches lisp source into a sort
;; of p-code (`lapcode') which takes up less space and can be interpreted
;; faster.  [`LAP' == `Lisp Assembly Program'.]
;; The user entry points are byte-compile-file and byte-recompile-directory.

;;; Todo:

;; - Turn "not bound at runtime" functions into autoloads.

;;; Code:

;; ========================================================================
;; Entry points:
;;      byte-recompile-directory, byte-compile-file,
;;      byte-recompile-file,
;;     batch-byte-compile, batch-byte-recompile-directory,
;;      byte-compile, compile-defun,
;;      display-call-tree
;; (byte-compile-buffer and byte-compile-and-load-file were turned off
;;  because they are not terribly useful and get in the way of completion.)

;; This version of the byte compiler has the following improvements:
;;  + optimization of compiled code:
;;    - removal of unreachable code;
;;    - removal of calls to side-effectless functions whose return-value
;;      is unused;
;;    - compile-time evaluation of safe constant forms, such as (consp nil)
;;      and (ash 1 6);
;;    - open-coding of literal lambdas;
;;    - peephole optimization of emitted code;
;;    - trivial functions are left uncompiled for speed.
;;  + support for inline functions;
;;  + compile-time evaluation of arbitrary expressions;
;;  + compile-time warning messages for:
;;    - functions being redefined with incompatible arglists;
;;    - functions being redefined as macros, or vice-versa;
;;    - functions or macros defined multiple times in the same file;
;;    - functions being called with the incorrect number of arguments;
;;    - functions being called which are not defined globally, in the
;;      file, or as autoloads;
;;    - assignment and reference of undeclared free variables;
;;    - various syntax errors;
;;  + correct compilation of nested defuns, defmacros, defvars and defsubsts;
;;  + correct compilation of top-level uses of macros;
;;  + the ability to generate a histogram of functions called.

;; User customization variables: M-x customize-group bytecomp

;; New Features:
;;
;;  o   The form `defsubst' is just like `defun', except that the function
;;      generated will be open-coded in compiled code which uses it.  This
;;      means that no function call will be generated, it will simply be
;;      spliced in.  Lisp functions calls are very slow, so this can be a
;;      big win.
;;
;;      You can generally accomplish the same thing with `defmacro', but in
;;      that case, the defined procedure can't be used as an argument to
;;      mapcar, etc.
;;
;;  o   You can also open-code one particular call to a function without
;;      open-coding all calls.  Use the 'inline' form to do this, like so:
;;
;;              (inline (foo 1 2 3))    ;; `foo' will be open-coded
;;      or...
;;              (inline                 ;;  `foo' and `baz' will be
;;               (foo 1 2 3 (bar 5))    ;; open-coded, but `bar' will not.
;;               (baz 0))
;;
;;  o   It is possible to open-code a function in the same file it is defined
;;      in without having to load that file before compiling it.  The
;;      byte-compiler has been modified to remember function definitions in
;;      the compilation environment in the same way that it remembers macro
;;      definitions.
;;
;;  o  Forms like ((lambda ...) ...) are open-coded.
;;
;;  o  The form `eval-when-compile' is like progn, except that the body
;;     is evaluated at compile-time.  When it appears at top-level, this
;;     is analogous to the Common Lisp idiom (eval-when (compile) ...).
;;     When it does not appear at top-level, it is similar to the
;;     Common Lisp #. reader macro (but not in interpreted code).
;;
;;  o  The form `eval-and-compile' is similar to eval-when-compile, but
;;      the whole form is evalled both at compile-time and at run-time.
;;
;;  o  The command compile-defun is analogous to eval-defun.
;;
;;  o  If you run byte-compile-file on a filename which is visited in a
;;     buffer, and that buffer is modified, you are asked whether you want
;;     to save the buffer before compiling.
;;
;;  o  byte-compiled files now start with the string `;ELC'.
;;     Some versions of `file' can be customized to recognize that.

(require 'backquote)
(require 'macroexp)
(require 'cconv)

;; During bootstrap, cl-loaddefs.el is not created yet, so loading cl-lib
;; doesn't setup autoloads for things like cl-every, which is why we have to
;; require cl-extra instead (bug#18804).
(require 'cl-extra)

(or (fboundp 'defsubst)
    ;; This really ought to be loaded already!
    (load "byte-run"))

;; The feature of compiling in a specific target Emacs version
;; has been turned off because compile time options are a bad idea.
(defgroup bytecomp nil
  "Emacs Lisp byte-compiler."
  :group 'lisp)

(defcustom emacs-lisp-file-regexp "\\.el\\'"
  "Regexp which matches Emacs Lisp source files.
If you change this, you might want to set `byte-compile-dest-file-function'."
  :group 'bytecomp
  :type 'regexp)

(defcustom byte-compile-dest-file-function nil
  "Function for the function `byte-compile-dest-file' to call.
It should take one argument, the name of an Emacs Lisp source
file name, and return the name of the compiled file."
  :group 'bytecomp
  :type '(choice (const nil) function)
  :version "23.2")

;; This enables file name handlers such as jka-compr
;; to remove parts of the file name that should not be copied
;; through to the output file name.
(defun byte-compiler-base-file-name (filename)
  (let ((handler (find-file-name-handler filename
                                         'byte-compiler-base-file-name)))
    (if handler
        (funcall handler 'byte-compiler-base-file-name filename)
      filename)))

(or (fboundp 'byte-compile-dest-file)
    ;; The user may want to redefine this along with emacs-lisp-file-regexp,
    ;; so only define it if it is undefined.
    ;; Note - redefining this function is obsolete as of 23.2.
    ;; Customize byte-compile-dest-file-function instead.
    (defun byte-compile-dest-file (filename)
      "Convert an Emacs Lisp source file name to a compiled file name.
If `byte-compile-dest-file-function' is non-nil, uses that
function to do the work.  Otherwise, if FILENAME matches
`emacs-lisp-file-regexp' (by default, files with the extension `.el'),
adds `c' to it; otherwise adds `.elc'."
      (if byte-compile-dest-file-function
          (funcall byte-compile-dest-file-function filename)
        (setq filename (file-name-sans-versions
                        (byte-compiler-base-file-name filename)))
        (cond ((string-match emacs-lisp-file-regexp filename)
               (concat (substring filename 0 (match-beginning 0)) ".elc"))
              (t (concat filename ".elc"))))))

;; This can be the 'byte-compile property of any symbol.
(autoload 'byte-compile-inline-expand "byte-opt")

;; This is the entry point to the lapcode optimizer pass1.
(autoload 'byte-optimize-form "byte-opt")
;; This is the entry point to the lapcode optimizer pass2.
(autoload 'byte-optimize-lapcode "byte-opt")
(autoload 'byte-compile-unfold-lambda "byte-opt")

;; This is the entry point to the decompiler, which is used by the
;; disassembler.  The disassembler just requires 'byte-compile, but
;; that doesn't define this function, so this seems to be a reasonable
;; thing to do.
(autoload 'byte-decompile-bytecode "byte-opt")

(defcustom byte-compile-verbose
  (and (not noninteractive) (> baud-rate search-slow-speed))
  "Non-nil means print messages describing progress of byte-compiler."
  :group 'bytecomp
  :type 'boolean)

(defcustom byte-optimize t
  "Enable optimization in the byte compiler.
Possible values are:
  nil      - no optimization
  t        - all optimizations
  `source' - source-level optimizations only
  `byte'   - code-level optimizations only"
  :group 'bytecomp
  :type '(choice (const :tag "none" nil)
                 (const :tag "all" t)
                 (const :tag "source-level" source)
                 (const :tag "byte-level" byte)))

(defcustom byte-compile-delete-errors nil
  "If non-nil, the optimizer may delete forms that may signal an error.
This includes variable references and calls to functions such as `car'."
  :group 'bytecomp
  :type 'boolean)

(defcustom byte-compile-cond-use-jump-table t
  "Compile `cond' clauses to a jump table implementation (using a hash-table)."
  :group 'bytecomp
  :type 'boolean)

(defvar byte-compile-dynamic nil
  "If non-nil, compile function bodies so they load lazily.
They are hidden in comments in the compiled file,
and each one is brought into core when the
function is called.

To enable this option, make it a file-local variable
in the source file you want it to apply to.
For example, add  -*-byte-compile-dynamic: t;-*- on the first line.

When this option is true, if you load the compiled file and then move it,
the functions you loaded will not be able to run.")
;;;###autoload(put 'byte-compile-dynamic 'safe-local-variable 'booleanp)

(defvar byte-compile-disable-print-circle nil
  "If non-nil, disable `print-circle' on printing a byte-compiled code.")
(make-obsolete-variable 'byte-compile-disable-print-circle nil "24.1")
;;;###autoload(put 'byte-compile-disable-print-circle 'safe-local-variable 'booleanp)

(defcustom byte-compile-dynamic-docstrings t
  "If non-nil, compile doc strings for lazy access.
We bury the doc strings of functions and variables inside comments in
the file, and bring them into core only when they are actually needed.

When this option is true, if you load the compiled file and then move it,
you won't be able to find the documentation of anything in that file.

To disable this option for a certain file, make it a file-local variable
in the source file.  For example, add this to the first line:
  -*-byte-compile-dynamic-docstrings:nil;-*-
You can also set the variable globally.

This option is enabled by default because it reduces Emacs memory usage."
  :group 'bytecomp
  :type 'boolean)
;;;###autoload(put 'byte-compile-dynamic-docstrings 'safe-local-variable 'booleanp)

(defconst byte-compile-log-buffer "*Compile-Log*"
  "Name of the byte-compiler's log buffer.")

(defcustom byte-optimize-log nil
  "If non-nil, the byte-compiler will log its optimizations.
If this is `source', then only source-level optimizations will be logged.
If it is `byte', then only byte-level optimizations will be logged.
The information is logged to `byte-compile-log-buffer'."
  :group 'bytecomp
  :type '(choice (const :tag "none" nil)
                 (const :tag "all" t)
                 (const :tag "source-level" source)
                 (const :tag "byte-level" byte)))

(defcustom byte-compile-error-on-warn nil
  "If true, the byte-compiler reports warnings with `error'."
  :group 'bytecomp
  :type 'boolean)

(defconst byte-compile-warning-types
  '(redefine callargs free-vars unresolved
             obsolete noruntime cl-functions interactive-only
             make-local mapcar constants suspicious lexical)
  "The list of warning types used when `byte-compile-warnings' is t.")
(defcustom byte-compile-warnings t
  "List of warnings that the byte-compiler should issue (t for all).

Elements of the list may be:

  free-vars   references to variables not in the current lexical scope.
  unresolved  calls to unknown functions.
  callargs    function calls with args that don't match the definition.
  redefine    function name redefined from a macro to ordinary function or vice
              versa, or redefined to take a different number of arguments.
  obsolete    obsolete variables and functions.
  noruntime   functions that may not be defined at runtime (typically
              defined only under `eval-when-compile').
  cl-functions    calls to runtime functions (as distinguished from macros and
                  aliases) from the old CL package (not the newer cl-lib).
  interactive-only
              commands that normally shouldn't be called from Lisp code.
  lexical     global/dynamic variables lacking a prefix.
  make-local  calls to make-variable-buffer-local that may be incorrect.
  mapcar      mapcar called for effect.
  constants   let-binding of, or assignment to, constants/nonvariables.
  suspicious  constructs that usually don't do what the coder wanted.

If the list begins with `not', then the remaining elements specify warnings to
suppress.  For example, (not mapcar) will suppress warnings about mapcar."
  :group 'bytecomp
  :type `(choice (const :tag "All" t)
                 (set :menu-tag "Some"
                      ,@(mapcar (lambda (x) `(const ,x))
                                byte-compile-warning-types))))

;;;###autoload
(put 'byte-compile-warnings 'safe-local-variable
     (lambda (v)
       (or (symbolp v)
           (null (delq nil (mapcar (lambda (x) (not (symbolp x))) v))))))

(defun byte-compile-warning-enabled-p (warning)
  "Return non-nil if WARNING is enabled, according to `byte-compile-warnings'."
  (or (eq byte-compile-warnings t)
      (if (eq (car byte-compile-warnings) 'not)
          (not (memq warning byte-compile-warnings))
        (memq warning byte-compile-warnings))))

;;;###autoload
(defun byte-compile-disable-warning (warning)
  "Change `byte-compile-warnings' to disable WARNING.
If `byte-compile-warnings' is t, set it to `(not WARNING)'.
Otherwise, if the first element is `not', add WARNING, else remove it.
Normally you should let-bind `byte-compile-warnings' before calling this,
else the global value will be modified."
  (setq byte-compile-warnings
        (cond ((eq byte-compile-warnings t)
               (list 'not warning))
              ((eq (car byte-compile-warnings) 'not)
               (if (memq warning byte-compile-warnings)
                   byte-compile-warnings
                 (append byte-compile-warnings (list warning))))
              (t
               (delq warning byte-compile-warnings)))))

;;;###autoload
(defun byte-compile-enable-warning (warning)
  "Change `byte-compile-warnings' to enable WARNING.
If `byte-compile-warnings' is t, do nothing.  Otherwise, if the
first element is `not', remove WARNING, else add it.
Normally you should let-bind `byte-compile-warnings' before calling this,
else the global value will be modified."
  (or (eq byte-compile-warnings t)
      (setq byte-compile-warnings
            (cond ((eq (car byte-compile-warnings) 'not)
                   (delq warning byte-compile-warnings))
                  ((memq warning byte-compile-warnings)
                   byte-compile-warnings)
                  (t
                   (append byte-compile-warnings (list warning)))))))

(defvar byte-compile-interactive-only-functions nil
  "List of commands that are not meant to be called from Lisp.")
(make-obsolete-variable 'byte-compile-interactive-only-functions
                        "use the `interactive-only' symbol property instead."
                        "24.4")

(defvar byte-compile-not-obsolete-vars nil
  "List of variables that shouldn't be reported as obsolete.")
(defvar byte-compile-global-not-obsolete-vars nil
  "Global list of variables that shouldn't be reported as obsolete.")

(defvar byte-compile-not-obsolete-funcs nil
  "List of functions that shouldn't be reported as obsolete.")

(defcustom byte-compile-generate-call-tree nil
  "Non-nil means collect call-graph information when compiling.
This records which functions were called and from where.
If the value is t, compilation displays the call graph when it finishes.
If the value is neither t nor nil, compilation asks you whether to display
the graph.

The call tree only lists functions called, not macros used. Those functions
which the byte-code interpreter knows about directly (eq, cons, etc.) are
not reported.

The call tree also lists those functions which are not known to be called
\(that is, to which no calls have been compiled).  Functions which can be
invoked interactively are excluded from this list."
  :group 'bytecomp
  :type '(choice (const :tag "Yes" t) (const :tag "No" nil)
                 (other :tag "Ask" lambda)))

(defvar byte-compile-call-tree nil
  "Alist of functions and their call tree.
Each element looks like

  (FUNCTION CALLERS CALLS)

where CALLERS is a list of functions that call FUNCTION, and CALLS
is a list of functions for which calls were generated while compiling
FUNCTION.")

(defcustom byte-compile-call-tree-sort 'name
  "If non-nil, sort the call tree.
The values `name', `callers', `calls', `calls+callers'
specify different fields to sort on."
  :group 'bytecomp
  :type '(choice (const name) (const callers) (const calls)
                 (const calls+callers) (const nil)))

(defvar byte-compile-debug nil)
(defvar byte-compile-jump-tables nil
  "List of all jump tables used during compilation of this form.")
(defvar byte-compile-constants nil
  "List of all constants encountered during compilation of this form.")
(defvar byte-compile-variables nil
  "List of all variables encountered during compilation of this form.")
(defvar byte-compile-bound-variables nil
  "List of dynamic variables bound in the context of the current form.
This list lives partly on the stack.")
(defvar byte-compile-lexical-variables nil
  "List of variables that have been treated as lexical.
Filled in `cconv-analyze-form' but initialized and consulted here.")
(defvar byte-compile-const-variables nil
  "List of variables declared as constants during compilation of this file.")
(defvar byte-compile-free-references)
(defvar byte-compile-free-assignments)

(defvar byte-compiler-error-flag)

(defun byte-compile-recurse-toplevel (form non-toplevel-case)
  "Implement `eval-when-compile' and `eval-and-compile'.
Return the compile-time value of FORM."
  ;; Macroexpand (not macroexpand-all!) form at toplevel in case it
  ;; expands into a toplevel-equivalent `progn'.  See CLHS section
  ;; 3.2.3.1, "Processing of Top Level Forms".  The semantics are very
  ;; subtle: see test/automated/bytecomp-tests.el for interesting
  ;; cases.
  (setf form (macroexp-macroexpand form byte-compile-macro-environment))
  (if (eq (car-safe form) 'progn)
      (cons 'progn
            (mapcar (lambda (subform)
                      (byte-compile-recurse-toplevel
                       subform non-toplevel-case))
                    (cdr form)))
    (funcall non-toplevel-case form)))

(defconst byte-compile-initial-macro-environment
  `(
    ;; (byte-compiler-options . (lambda (&rest forms)
    ;;                         (apply 'byte-compiler-options-handler forms)))
    (declare-function . byte-compile-macroexpand-declare-function)
    (eval-when-compile . ,(lambda (&rest body)
                            (let ((result nil))
                              (byte-compile-recurse-toplevel
                               (macroexp-progn body)
                               (lambda (form)
                                 ;; Insulate the following variables
                                 ;; against changes made in the
                                 ;; subsidiary compilation.  This
                                 ;; prevents spurious warning
                                 ;; messages: "not defined at runtime"
                                 ;; etc.
                                 (let ((byte-compile-unresolved-functions
                                        byte-compile-unresolved-functions)
                                       (byte-compile-new-defuns
                                        byte-compile-new-defuns))
                                   (setf result
                                         (byte-compile-eval
                                          (byte-compile-top-level
                                           (byte-compile-preprocess form)))))))
                              (list 'quote result))))
    (eval-and-compile . ,(lambda (&rest body)
                           (byte-compile-recurse-toplevel
                            (macroexp-progn body)
                            (lambda (form)
                              ;; Don't compile here, since we don't know
                              ;; whether to compile as byte-compile-form
                              ;; or byte-compile-file-form.
                              (let ((expanded
                                     (macroexpand-all
                                      form
                                      macroexpand-all-environment)))
                                (eval expanded lexical-binding)
                                expanded))))))
  "The default macro-environment passed to macroexpand by the compiler.
Placing a macro here will cause a macro to have different semantics when
expanded by the compiler as when expanded by the interpreter.")

(defvar byte-compile-macro-environment byte-compile-initial-macro-environment
  "Alist of macros defined in the file being compiled.
Each element looks like (MACRONAME . DEFINITION).  It is
\(MACRONAME . nil) when a macro is redefined as a function.")

(defvar byte-compile-function-environment nil
  "Alist of functions defined in the file being compiled.
This is so we can inline them when necessary.
Each element looks like (FUNCTIONNAME . DEFINITION).  It is
\(FUNCTIONNAME . nil) when a function is redefined as a macro.
It is \(FUNCTIONNAME . t) when all we know is that it was defined,
and we don't know the definition.  For an autoloaded function, DEFINITION
has the form (autoload . FILENAME).")

(defvar byte-compile-unresolved-functions nil
  "Alist of undefined functions to which calls have been compiled.
This variable is only significant whilst compiling an entire buffer.
Used for warnings when a function is not known to be defined or is later
defined with incorrect args.")

(defvar byte-compile-noruntime-functions nil
  "Alist of functions called that may not be defined when the compiled code is run.
Used for warnings about calling a function that is defined during compilation
but won't necessarily be defined when the compiled file is loaded.")

(defvar byte-compile-new-defuns nil
  "List of (runtime) functions defined in this compilation run.
This variable is used to qualify `byte-compile-noruntime-functions' when
outputting warnings about functions not being defined at runtime.")

;; Variables for lexical binding
(defvar byte-compile--lexical-environment nil
  "The current lexical environment.")

(defvar byte-compile-tag-number 0)
(defvar byte-compile-output nil
  "Alist describing contents to put in byte code string.
Each element is (INDEX . VALUE)")
(defvar byte-compile-depth 0 "Current depth of execution stack.")
(defvar byte-compile-maxdepth 0 "Maximum depth of execution stack.")

\f
;;; The byte codes; this information is duplicated in bytecomp.c

(defvar byte-code-vector nil
  "An array containing byte-code names indexed by byte-code values.")

(defvar byte-stack+-info nil
  "An array with the stack adjustment for each byte-code.")

(defmacro byte-defop (opcode stack-adjust opname &optional docstring)
  ;; This is a speed-hack for building the byte-code-vector at compile-time.
  ;; We fill in the vector at macroexpand-time, and then after the last call
  ;; to byte-defop, we write the vector out as a constant instead of writing
  ;; out a bunch of calls to aset.
  ;; Actually, we don't fill in the vector itself, because that could make
  ;; it problematic to compile big changes to this compiler; we store the
  ;; values on its plist, and remove them later in -extrude.
  (let ((v1 (or (get 'byte-code-vector 'tmp-compile-time-value)
                (put 'byte-code-vector 'tmp-compile-time-value
                     (make-vector 256 nil))))
        (v2 (or (get 'byte-stack+-info 'tmp-compile-time-value)
                (put 'byte-stack+-info 'tmp-compile-time-value
                     (make-vector 256 nil)))))
    (aset v1 opcode opname)
    (aset v2 opcode stack-adjust))
  (if docstring
      (list 'defconst opname opcode (concat "Byte code opcode " docstring "."))
      (list 'defconst opname opcode)))

(defmacro byte-extrude-byte-code-vectors ()
  (prog1 (list 'setq 'byte-code-vector
                     (get 'byte-code-vector 'tmp-compile-time-value)
                     'byte-stack+-info
                     (get 'byte-stack+-info 'tmp-compile-time-value))
    (put 'byte-code-vector 'tmp-compile-time-value nil)
    (put 'byte-stack+-info 'tmp-compile-time-value nil)))


;; These opcodes are special in that they pack their argument into the
;; opcode word.
;;
(byte-defop   0  1 byte-stack-ref "for stack reference")
(byte-defop   8  1 byte-varref  "for variable reference")
(byte-defop  16 -1 byte-varset  "for setting a variable")
(byte-defop  24 -1 byte-varbind "for binding a variable")
(byte-defop  32  0 byte-call    "for calling a function")
(byte-defop  40  0 byte-unbind  "for unbinding special bindings")
;; codes 8-47 are consumed by the preceding opcodes

;; New (in Emacs-24.4) bytecodes for more efficient handling of non-local exits
;; (especially useful in lexical-binding code).
(byte-defop  48  0 byte-pophandler)
(byte-defop  50 -1 byte-pushcatch)
(byte-defop  49 -1 byte-pushconditioncase)

;; unused: 51-55

(byte-defop  56 -1 byte-nth)
(byte-defop  57  0 byte-symbolp)
(byte-defop  58  0 byte-consp)
(byte-defop  59  0 byte-stringp)
(byte-defop  60  0 byte-listp)
(byte-defop  61 -1 byte-eq)
(byte-defop  62 -1 byte-memq)
(byte-defop  63  0 byte-not)
(byte-defop  64  0 byte-car)
(byte-defop  65  0 byte-cdr)
(byte-defop  66 -1 byte-cons)
(byte-defop  67  0 byte-list1)
(byte-defop  68 -1 byte-list2)
(byte-defop  69 -2 byte-list3)
(byte-defop  70 -3 byte-list4)
(byte-defop  71  0 byte-length)
(byte-defop  72 -1 byte-aref)
(byte-defop  73 -2 byte-aset)
(byte-defop  74  0 byte-symbol-value)
(byte-defop  75  0 byte-symbol-function) ; this was commented out
(byte-defop  76 -1 byte-set)
(byte-defop  77 -1 byte-fset) ; this was commented out
(byte-defop  78 -1 byte-get)
(byte-defop  79 -2 byte-substring)
(byte-defop  80 -1 byte-concat2)
(byte-defop  81 -2 byte-concat3)
(byte-defop  82 -3 byte-concat4)
(byte-defop  83  0 byte-sub1)
(byte-defop  84  0 byte-add1)
(byte-defop  85 -1 byte-eqlsign)
(byte-defop  86 -1 byte-gtr)
(byte-defop  87 -1 byte-lss)
(byte-defop  88 -1 byte-leq)
(byte-defop  89 -1 byte-geq)
(byte-defop  90 -1 byte-diff)
(byte-defop  91  0 byte-negate)
(byte-defop  92 -1 byte-plus)
(byte-defop  93 -1 byte-max)
(byte-defop  94 -1 byte-min)
(byte-defop  95 -1 byte-mult) ; v19 only
(byte-defop  96  1 byte-point)
(byte-defop  98  0 byte-goto-char)
(byte-defop  99  0 byte-insert)
(byte-defop 100  1 byte-point-max)
(byte-defop 101  1 byte-point-min)
(byte-defop 102  0 byte-char-after)
(byte-defop 103  1 byte-following-char)
(byte-defop 104  1 byte-preceding-char)
(byte-defop 105  1 byte-current-column)
(byte-defop 106  0 byte-indent-to)
(byte-defop 107  0 byte-scan-buffer-OBSOLETE) ; no longer generated as of v18
(byte-defop 108  1 byte-eolp)
(byte-defop 109  1 byte-eobp)
(byte-defop 110  1 byte-bolp)
(byte-defop 111  1 byte-bobp)
(byte-defop 112  1 byte-current-buffer)
(byte-defop 113  0 byte-set-buffer)
(byte-defop 114  0 byte-save-current-buffer
  "To make a binding to record the current buffer")
(byte-defop 115  0 byte-set-mark-OBSOLETE)
(byte-defop 116  1 byte-interactive-p-OBSOLETE)

;; These ops are new to v19
(byte-defop 117  0 byte-forward-char)
(byte-defop 118  0 byte-forward-word)
(byte-defop 119 -1 byte-skip-chars-forward)
(byte-defop 120 -1 byte-skip-chars-backward)
(byte-defop 121  0 byte-forward-line)
(byte-defop 122  0 byte-char-syntax)
(byte-defop 123 -1 byte-buffer-substring)
(byte-defop 124 -1 byte-delete-region)
(byte-defop 125 -1 byte-narrow-to-region)
(byte-defop 126  1 byte-widen)
(byte-defop 127  0 byte-end-of-line)

;; unused: 128

;; These store their argument in the next two bytes
(byte-defop 129  1 byte-constant2
   "for reference to a constant with vector index >= byte-constant-limit")
(byte-defop 130  0 byte-goto "for unconditional jump")
(byte-defop 131 -1 byte-goto-if-nil "to pop value and jump if it's nil")
(byte-defop 132 -1 byte-goto-if-not-nil "to pop value and jump if it's not nil")
(byte-defop 133 -1 byte-goto-if-nil-else-pop
  "to examine top-of-stack, jump and don't pop it if it's nil,
otherwise pop it")
(byte-defop 134 -1 byte-goto-if-not-nil-else-pop
  "to examine top-of-stack, jump and don't pop it if it's non nil,
otherwise pop it")

(byte-defop 135 -1 byte-return "to pop a value and return it from `byte-code'")
(byte-defop 136 -1 byte-discard "to discard one value from stack")
(byte-defop 137  1 byte-dup     "to duplicate the top of the stack")

(byte-defop 138  0 byte-save-excursion
  "to make a binding to record the buffer, point and mark")
(byte-defop 139  0 byte-save-window-excursion-OBSOLETE
  "to make a binding to record entire window configuration")
(byte-defop 140  0 byte-save-restriction
  "to make a binding to record the current buffer clipping restrictions")
(byte-defop 141 -1 byte-catch
  "for catch.  Takes, on stack, the tag and an expression for the body")
(byte-defop 142 -1 byte-unwind-protect
  "for unwind-protect.  Takes, on stack, an expression for the unwind-action")

;; For condition-case.  Takes, on stack, the variable to bind,
;; an expression for the body, and a list of clauses.
(byte-defop 143 -2 byte-condition-case)

(byte-defop 144  0 byte-temp-output-buffer-setup-OBSOLETE)
(byte-defop 145 -1 byte-temp-output-buffer-show-OBSOLETE)

;; these ops are new to v19

;; To unbind back to the beginning of this frame.
;; Not used yet, but will be needed for tail-recursion elimination.
(byte-defop 146  0 byte-unbind-all)

;; these ops are new to v19
(byte-defop 147 -2 byte-set-marker)
(byte-defop 148  0 byte-match-beginning)
(byte-defop 149  0 byte-match-end)
(byte-defop 150  0 byte-upcase)
(byte-defop 151  0 byte-downcase)
(byte-defop 152 -1 byte-string=)
(byte-defop 153 -1 byte-string<)
(byte-defop 154 -1 byte-equal)
(byte-defop 155 -1 byte-nthcdr)
(byte-defop 156 -1 byte-elt)
(byte-defop 157 -1 byte-member)
(byte-defop 158 -1 byte-assq)
(byte-defop 159  0 byte-nreverse)
(byte-defop 160 -1 byte-setcar)
(byte-defop 161 -1 byte-setcdr)
(byte-defop 162  0 byte-car-safe)
(byte-defop 163  0 byte-cdr-safe)
(byte-defop 164 -1 byte-nconc)
(byte-defop 165 -1 byte-quo)
(byte-defop 166 -1 byte-rem)
(byte-defop 167  0 byte-numberp)
(byte-defop 168  0 byte-integerp)

;; unused: 169-174
(byte-defop 175 nil byte-listN)
(byte-defop 176 nil byte-concatN)
(byte-defop 177 nil byte-insertN)

(byte-defop 178 -1 byte-stack-set)      ; Stack offset in following one byte.
(byte-defop 179 -1 byte-stack-set2)     ; Stack offset in following two bytes.

;; If (following one byte & 0x80) == 0
;;    discard (following one byte & 0x7F) stack entries
;; else
;;    discard (following one byte & 0x7F) stack entries _underneath_ TOS
;;    (that is, if the operand = 0x83,  ... X Y Z T  =>  ... T)
(byte-defop 182 nil byte-discardN)
;; `byte-discardN-preserve-tos' is a pseudo-op that gets turned into
;; `byte-discardN' with the high bit in the operand set (by
;; `byte-compile-lapcode').
(defconst byte-discardN-preserve-tos byte-discardN)

(byte-defop 183 -2 byte-switch
 "to take a hash table and a value from the stack, and jump to the address
the value maps to, if any.")

;; unused: 182-191

(byte-defop 192  1 byte-constant        "for reference to a constant")
;; codes 193-255 are consumed by byte-constant.
(defconst byte-constant-limit 64
  "Exclusive maximum index usable in the `byte-constant' opcode.")

(defconst byte-goto-ops '(byte-goto byte-goto-if-nil byte-goto-if-not-nil
                          byte-goto-if-nil-else-pop
                          byte-goto-if-not-nil-else-pop
                          byte-pushcatch byte-pushconditioncase)
  "List of byte-codes whose offset is a pc.")

(defconst byte-goto-always-pop-ops '(byte-goto-if-nil byte-goto-if-not-nil))

(byte-extrude-byte-code-vectors)
\f
;;; lapcode generator
;;
;; the byte-compiler now does source -> lapcode -> bytecode instead of
;; source -> bytecode, because it's a lot easier to make optimizations
;; on lapcode than on bytecode.
;;
;; Elements of the lapcode list are of the form (<instruction> . <parameter>)
;; where instruction is a symbol naming a byte-code instruction,
;; and parameter is an argument to that instruction, if any.
;;
;; The instruction can be the pseudo-op TAG, which means that this position
;; in the instruction stream is a target of a goto.  (car PARAMETER) will be
;; the PC for this location, and the whole instruction "(TAG pc)" will be the
;; parameter for some goto op.
;;
;; If the operation is varbind, varref, varset or push-constant, then the
;; parameter is (variable/constant . index_in_constant_vector).
;;
;; First, the source code is macroexpanded and optimized in various ways.
;; Then the resultant code is compiled into lapcode.  Another set of
;; optimizations are then run over the lapcode.  Then the variables and
;; constants referenced by the lapcode are collected and placed in the
;; constants-vector.  (This happens now so that variables referenced by dead
;; code don't consume space.)  And finally, the lapcode is transformed into
;; compacted byte-code.
;;
;; A distinction is made between variables and constants because the variable-
;; referencing instructions are more sensitive to the variables being near the
;; front of the constants-vector than the constant-referencing instructions.
;; Also, this lets us notice references to free variables.

(defmacro byte-compile-push-bytecodes (&rest args)
  "Push bytes onto BVAR, and increment CVAR by the number of bytes pushed.
BVAR and CVAR are variables which are updated after evaluating
all the arguments.

\(fn BYTE1 BYTE2 ... BYTEn BVAR CVAR)"
  (let ((byte-exprs (butlast args 2))
        (bytes-var (car (last args 2)))
        (pc-var (car (last args))))
    `(setq ,bytes-var ,(if (null (cdr byte-exprs))
                           `(progn (cl-assert (<= 0 ,(car byte-exprs)))
                                   (cons ,@byte-exprs ,bytes-var))
                         `(nconc (list ,@(reverse byte-exprs)) ,bytes-var))
           ,pc-var (+ ,(length byte-exprs) ,pc-var))))

(defmacro byte-compile-push-bytecode-const2 (opcode const2 bytes pc)
  "Push OPCODE and the two-byte constant CONST2 onto BYTES, and add 3 to PC.
CONST2 may be evaluated multiple times."
  `(byte-compile-push-bytecodes ,opcode (logand ,const2 255) (lsh ,const2 -8)
                                ,bytes ,pc))

(defun byte-compile-lapcode (lap)
  "Turns lapcode into bytecode.  The lapcode is destroyed."
  ;; Lapcode modifications: changes the ID of a tag to be the tag's PC.
  (let ((pc 0)                  ; Program counter
        op off                  ; Operation & offset
        opcode                  ; numeric value of OP
        (bytes '())             ; Put the output bytes here
        (patchlist nil))        ; List of gotos to patch
    (dolist (lap-entry lap)
      (setq op (car lap-entry)
            off (cdr lap-entry))
      (cond
       ((not (symbolp op))
        (error "Non-symbolic opcode `%s'" op))
       ((eq op 'TAG)
        (setcar off pc))
       (t
        (setq opcode
              (if (eq op 'byte-discardN-preserve-tos)
                  ;; byte-discardN-preserve-tos is a pseudo op, which
                  ;; is actually the same as byte-discardN
                  ;; with a modified argument.
                  byte-discardN
                (symbol-value op)))
        (cond ((memq op byte-goto-ops)
               ;; goto
               (byte-compile-push-bytecodes opcode nil (cdr off) bytes pc)
               (push bytes patchlist))
              ((or (and (consp off)
                        ;; Variable or constant reference
                        (progn
                          (setq off (cdr off))
                          (eq op 'byte-constant)))
                   (and (eq op 'byte-constant)
                        (integerp off)))
               ;; constant ref
               (if (< off byte-constant-limit)
                   (byte-compile-push-bytecodes (+ byte-constant off)
                                                bytes pc)
                 (byte-compile-push-bytecode-const2 byte-constant2 off
                                                    bytes pc)))
              ((and (= opcode byte-stack-set)
                    (> off 255))
               ;; Use the two-byte version of byte-stack-set if the
               ;; offset is too large for the normal version.
               (byte-compile-push-bytecode-const2 byte-stack-set2 off
                                                  bytes pc))
              ((and (>= opcode byte-listN)
                    (< opcode byte-discardN))
               ;; These insns all put their operand into one extra byte.
               (byte-compile-push-bytecodes opcode off bytes pc))
              ((= opcode byte-discardN)
               ;; byte-discardN is weird in that it encodes a flag in the
               ;; top bit of its one-byte argument.  If the argument is
               ;; too large to fit in 7 bits, the opcode can be repeated.
               (let ((flag (if (eq op 'byte-discardN-preserve-tos) #x80 0)))
                 (while (> off #x7f)
                   (byte-compile-push-bytecodes opcode (logior #x7f flag)
                                                bytes pc)
                   (setq off (- off #x7f)))
                 (byte-compile-push-bytecodes opcode (logior off flag)
                                              bytes pc)))
              ((null off)
               ;; opcode that doesn't use OFF
               (byte-compile-push-bytecodes opcode bytes pc))
              ((and (eq opcode byte-stack-ref) (eq off 0))
               ;; (stack-ref 0) is really just another name for `dup'.
               (debug)                 ;FIXME: When would this happen?
               (byte-compile-push-bytecodes byte-dup bytes pc))
              ;; The following three cases are for the special
              ;; insns that encode their operand into 0, 1, or 2
              ;; extra bytes depending on its magnitude.
              ((< off 6)
               (byte-compile-push-bytecodes (+ opcode off) bytes pc))
              ((< off 256)
               (byte-compile-push-bytecodes (+ opcode 6) off bytes pc))
              (t
               (byte-compile-push-bytecode-const2 (+ opcode 7) off
                                                  bytes pc))))))
    ;;(if (not (= pc (length bytes)))
    ;;    (error "Compiler error: pc mismatch - %s %s" pc (length bytes)))
    ;; Patch tag PCs into absolute jumps.
    (dolist (bytes-tail patchlist)
      (setq pc (caar bytes-tail))       ; Pick PC from goto's tag.
      ;; Splits PC's value into 2 bytes. The jump address is
      ;; "reconstructed" by the `FETCH2' macro in `bytecode.c'.
      (setcar (cdr bytes-tail) (logand pc 255))
      (setcar bytes-tail (lsh pc -8))
      ;; FIXME: Replace this by some workaround.
      (if (> (car bytes-tail) 255) (error "Bytecode overflow")))

    ;; Similarly, replace TAGs in all jump tables with the correct PC index.
    (dolist (hash-table byte-compile-jump-tables)
      (maphash #'(lambda (value tag)
                   (setq pc (cadr tag))
                   ;; We don't need to split PC here, as it is stored as a lisp
                   ;; object in the hash table (whereas other goto-* ops store
                   ;; it within 2 bytes in the byte string).
                   (puthash value pc hash-table))
               hash-table))
    (apply 'unibyte-string (nreverse bytes))))

\f
;;; compile-time evaluation

(defun byte-compile-cl-file-p (file)
  "Return non-nil if FILE is one of the CL files."
  (and (stringp file)
       (string-match "^cl\\.el" (file-name-nondirectory file))))

(defun byte-compile-eval (form)
  "Eval FORM and mark the functions defined therein.
Each function's symbol gets added to `byte-compile-noruntime-functions'."
  (let ((hist-orig load-history)
        (hist-nil-orig current-load-list))
    (prog1 (eval form lexical-binding)
      (when (byte-compile-warning-enabled-p 'noruntime)
        (let ((hist-new load-history)
              (hist-nil-new current-load-list))
          ;; Go through load-history, look for newly loaded files
          ;; and mark all the functions defined therein.
          (while (and hist-new (not (eq hist-new hist-orig)))
            (let ((xs (pop hist-new))
                  old-autoloads)
              ;; Make sure the file was not already loaded before.
              (unless (assoc (car xs) hist-orig)
                (dolist (s xs)
                  (cond
                   ((and (consp s) (eq t (car s)))
                    (push (cdr s) old-autoloads))
                   ((and (consp s) (memq (car s) '(autoload defun)))
                    (unless (memq (cdr s) old-autoloads)
                      (push (cdr s) byte-compile-noruntime-functions))))))))
          ;; Go through current-load-list for the locally defined funs.
          (let (old-autoloads)
            (while (and hist-nil-new (not (eq hist-nil-new hist-nil-orig)))
              (let ((s (pop hist-nil-new)))
                (when (and (symbolp s) (not (memq s old-autoloads)))
                  (push s byte-compile-noruntime-functions))
                (when (and (consp s) (eq t (car s)))
                  (push (cdr s) old-autoloads)))))))
      (when (byte-compile-warning-enabled-p 'cl-functions)
        (let ((hist-new load-history))
          ;; Go through load-history, looking for the cl files.
          ;; Since new files are added at the start of load-history,
          ;; we scan the new history until the tail matches the old.
          (while (and (not byte-compile-cl-functions)
                      hist-new (not (eq hist-new hist-orig)))
            ;; We used to check if the file had already been loaded,
            ;; but it is better to check non-nil byte-compile-cl-functions.
            (and (byte-compile-cl-file-p (car (pop hist-new)))
                 (byte-compile-find-cl-functions))))))))

(defun byte-compile-eval-before-compile (form)
  "Evaluate FORM for `eval-and-compile'."
  (let ((hist-nil-orig current-load-list))
    (prog1 (eval form lexical-binding)
      ;; (eval-and-compile (require 'cl) turns off warnings for cl functions.
      ;; FIXME Why does it do that - just as a hack?
      ;; There are other ways to do this nowadays.
      (let ((tem current-load-list))
        (while (not (eq tem hist-nil-orig))
          (when (equal (car tem) '(require . cl))
            (byte-compile-disable-warning 'cl-functions))
          (setq tem (cdr tem)))))))
\f
;;; byte compiler messages

(defvar byte-compile-current-form nil)
(defvar byte-compile-dest-file nil)
(defvar byte-compile-current-file nil)
(defvar byte-compile-current-group nil)
(defvar byte-compile-current-buffer nil)

;; Log something that isn't a warning.
(defmacro byte-compile-log (format-string &rest args)
  `(and
    byte-optimize
    (memq byte-optimize-log '(t source))
    (let ((print-escape-newlines t)
          (print-level 4)
          (print-length 4))
      (byte-compile-log-1
       (format-message
        ,format-string
        ,@(mapcar
           (lambda (x) (if (symbolp x) (list 'prin1-to-string x) x))
           args))))))

;; Log something that isn't a warning.
(defun byte-compile-log-1 (string)
  (with-current-buffer byte-compile-log-buffer
    (let ((inhibit-read-only t))
      (goto-char (point-max))
      (byte-compile-warning-prefix nil nil)
      (cond (noninteractive
             (message " %s" string))
            (t
             (insert (format "%s\n" string)))))))

(defvar byte-compile-read-position nil
  "Character position we began the last `read' from.")
(defvar byte-compile-last-position nil
  "Last known character position in the input.")

;; copied from gnus-util.el
(defsubst byte-compile-delete-first (elt list)
  (if (eq (car list) elt)
      (cdr list)
    (let ((total list))
      (while (and (cdr list)
                  (not (eq (cadr list) elt)))
        (setq list (cdr list)))
      (when (cdr list)
        (setcdr list (cddr list)))
      total)))

;; The purpose of `byte-compile-set-symbol-position' is to attempt to
;; set `byte-compile-last-position' to the "current position" in the
;; raw source code.  This is used for warning and error messages.
;;
;; The function should be called for most occurrences of symbols in
;; the forms being compiled, strictly in the order they occur in the
;; source code.  It should never be called twice for any single
;; occurrence, and should not be called for symbols generated by the
;; byte compiler itself.
;;
;; The function works by scanning the elements in the alist
;; `read-symbol-positions-list' for the next match for the symbol
;; after the current value of `byte-compile-last-position', setting
;; that variable to the match's character position, then deleting the
;; matching element from the list.  Thus the new value for
;; `byte-compile-last-position' is later than the old value unless,
;; perhaps, ALLOW-PREVIOUS is non-nil.
;;
;; So your're probably asking yourself: Isn't this function a gross
;; hack?  And the answer, of course, would be yes.
(defun byte-compile-set-symbol-position (sym &optional allow-previous)
  (when byte-compile-read-position
    (let ((last byte-compile-last-position)
          entry)
      (while (progn
               (setq entry (assq sym read-symbol-positions-list))
               (when entry
                 (setq byte-compile-last-position
                       (+ byte-compile-read-position (cdr entry))
                       read-symbol-positions-list
                       (byte-compile-delete-first
                        entry read-symbol-positions-list)))
               (and entry
                    (or (and allow-previous
                             (not (= last byte-compile-last-position)))
                        (> last byte-compile-last-position))))))))

(defvar byte-compile-last-warned-form nil)
(defvar byte-compile-last-logged-file nil)
(defvar byte-compile-root-dir nil
  "Directory relative to which file names in error messages are written.")

;; FIXME: We should maybe extend abbreviate-file-name with an optional DIR
;; argument to try and use a relative file-name.
(defun byte-compile-abbreviate-file (file &optional dir)
  (let ((f1 (abbreviate-file-name file))
        (f2 (file-relative-name file dir)))
    (if (< (length f2) (length f1)) f2 f1)))

;; This is used as warning-prefix for the compiler.
;; It is always called with the warnings buffer current.
(defun byte-compile-warning-prefix (level entry)
  (let* ((inhibit-read-only t)
         (dir (or byte-compile-root-dir default-directory))
         (file (cond ((stringp byte-compile-current-file)
                      (format "%s:" (byte-compile-abbreviate-file
                                     byte-compile-current-file dir)))
                     ((bufferp byte-compile-current-file)
                      (format "Buffer %s:"
                              (buffer-name byte-compile-current-file)))
                     ;; We might be simply loading a file that
                     ;; contains explicit calls to byte-compile functions.
                     ((stringp load-file-name)
                      (format "%s:" (byte-compile-abbreviate-file
                                     load-file-name dir)))
                     (t "")))
         (pos (if (and byte-compile-current-file
                       (integerp byte-compile-read-position))
                  (with-current-buffer byte-compile-current-buffer
                    (format "%d:%d:"
                            (save-excursion
                              (goto-char byte-compile-last-position)
                              (1+ (count-lines (point-min) (point-at-bol))))
                            (save-excursion
                              (goto-char byte-compile-last-position)
                              (1+ (current-column)))))
                ""))
         (form (if (eq byte-compile-current-form :end) "end of data"
                 (or byte-compile-current-form "toplevel form"))))
    (when (or (and byte-compile-current-file
                   (not (equal byte-compile-current-file
                               byte-compile-last-logged-file)))
              (and byte-compile-current-form
                   (not (eq byte-compile-current-form
                            byte-compile-last-warned-form))))
      (insert (format "\nIn %s:\n" form)))
    (when level
      (insert (format "%s%s" file pos))))
  (setq byte-compile-last-logged-file byte-compile-current-file
        byte-compile-last-warned-form byte-compile-current-form)
  entry)

;; This no-op function is used as the value of warning-series
;; to tell inner calls to displaying-byte-compile-warnings
;; not to bind warning-series.
(defun byte-compile-warning-series (&rest _ignore)
  nil)

;; (compile-mode) will cause this to be loaded.
(declare-function compilation-forget-errors "compile" ())

;; Log the start of a file in `byte-compile-log-buffer', and mark it as done.
;; Return the position of the start of the page in the log buffer.
;; But do nothing in batch mode.
(defun byte-compile-log-file ()
  (and (not (equal byte-compile-current-file byte-compile-last-logged-file))
       (not noninteractive)
       (with-current-buffer (get-buffer-create byte-compile-log-buffer)
         (goto-char (point-max))
         (let* ((inhibit-read-only t)
                (dir (and byte-compile-current-file
                          (file-name-directory byte-compile-current-file)))
                (was-same (equal default-directory dir))
                pt)
           (when dir
             (unless was-same
               (insert (format-message "Leaving directory `%s'\n"
                                       default-directory))))
           (unless (bolp)
             (insert "\n"))
           (setq pt (point-marker))
           (if byte-compile-current-file
               (insert "\f\nCompiling "
                       (if (stringp byte-compile-current-file)
                           (concat "file " byte-compile-current-file)
                         (concat "buffer "
                                 (buffer-name byte-compile-current-file)))
                       " at " (current-time-string) "\n")
             (insert "\f\nCompiling no file at " (current-time-string) "\n"))
           (when dir
             (setq default-directory dir)
             (unless was-same
               (insert (format-message "Entering directory `%s'\n"
                                       default-directory))))
           (setq byte-compile-last-logged-file byte-compile-current-file
                 byte-compile-last-warned-form nil)
           ;; Do this after setting default-directory.
           (unless (derived-mode-p 'compilation-mode) (compilation-mode))
           (compilation-forget-errors)
           pt))))

(defun byte-compile-log-warning (string &optional fill level)
  "Log a message STRING in `byte-compile-log-buffer'.
Also log the current function and file if not already done.  If
FILL is non-nil, set `warning-fill-prefix' to four spaces.  LEVEL
is the warning level (`:warning' or `:error').  Do not call this
function directly; use `byte-compile-warn' or
`byte-compile-report-error' instead."
  (let ((warning-prefix-function 'byte-compile-warning-prefix)
        (warning-type-format "")
        (warning-fill-prefix (if fill "    ")))
    (display-warning 'bytecomp string level byte-compile-log-buffer)))

(defun byte-compile-warn (format &rest args)
  "Issue a byte compiler warning; use (format-message FORMAT ARGS...) for message."
  (setq format (apply #'format-message format args))
  (if byte-compile-error-on-warn
      (error "%s" format)               ; byte-compile-file catches and logs it
    (byte-compile-log-warning format t :warning)))

(defun byte-compile-warn-obsolete (symbol)
  "Warn that SYMBOL (a variable or function) is obsolete."
  (when (byte-compile-warning-enabled-p 'obsolete)
    (let* ((funcp (get symbol 'byte-obsolete-info))
           (msg (macroexp--obsolete-warning
                 symbol
                 (or funcp (get symbol 'byte-obsolete-variable))
                 (if funcp "function" "variable"))))
      (unless (and funcp (memq symbol byte-compile-not-obsolete-funcs))
        (byte-compile-warn "%s" msg)))))

(defun byte-compile-report-error (error-info &optional fill)
  "Report Lisp error in compilation.
ERROR-INFO is the error data, in the form of either (ERROR-SYMBOL . DATA)
or STRING.  If FILL is non-nil, set ‘warning-fill-prefix’ to four spaces
when printing the error message."
  (setq byte-compiler-error-flag t)
  (byte-compile-log-warning
   (if (stringp error-info) error-info
     (error-message-string error-info))
   fill :error))
\f
;;; sanity-checking arglists

(defun byte-compile-fdefinition (name macro-p)
  ;; If a function has an entry saying (FUNCTION . t).
  ;; that means we know it is defined but we don't know how.
  ;; If a function has an entry saying (FUNCTION . nil),
  ;; that means treat it as not defined.
  (let* ((list (if macro-p
                   byte-compile-macro-environment
                 byte-compile-function-environment))
         (env (cdr (assq name list))))
    (or env
        (let ((fn name))
          (while (and (symbolp fn)
                      (fboundp fn)
                      (or (symbolp (symbol-function fn))
                          (consp (symbol-function fn))
                          (and (not macro-p)
                               (byte-code-function-p (symbol-function fn)))))
            (setq fn (symbol-function fn)))
          (let ((advertised (gethash (if (and (symbolp fn) (fboundp fn))
                                         ;; Could be a subr.
                                         (symbol-function fn)
                                       fn)
                                     advertised-signature-table t)))
            (cond
             ((listp advertised)
              (if macro-p
                  `(macro lambda ,advertised)
                `(lambda ,advertised)))
             ((and (not macro-p) (byte-code-function-p fn)) fn)
             ((not (consp fn)) nil)
             ((eq 'macro (car fn)) (cdr fn))
             (macro-p nil)
             ((eq 'autoload (car fn)) nil)
             (t fn)))))))

(defun byte-compile-arglist-signature (arglist)
  (cond
   ;; New style byte-code arglist.
   ((integerp arglist)
    (cons (logand arglist 127)             ;Mandatory.
          (if (zerop (logand arglist 128)) ;No &rest.
              (lsh arglist -8))))          ;Nonrest.
   ;; Old style byte-code, or interpreted function.
   ((listp arglist)
    (let ((args 0)
          opts
          restp)
      (while arglist
        (cond ((eq (car arglist) '&optional)
               (or opts (setq opts 0)))
              ((eq (car arglist) '&rest)
               (if (cdr arglist)
                   (setq restp t
                         arglist nil)))
              (t
               (if opts
                   (setq opts (1+ opts))
                 (setq args (1+ args)))))
        (setq arglist (cdr arglist)))
      (cons args (if restp nil (if opts (+ args opts) args)))))
   ;; Unknown arglist.
   (t '(0))))


(defun byte-compile-arglist-signatures-congruent-p (old new)
  (not (or
         (> (car new) (car old))  ; requires more args now
         (and (null (cdr old))    ; took rest-args, doesn't any more
              (cdr new))
         (and (cdr new) (cdr old) ; can't take as many args now
              (< (cdr new) (cdr old)))
         )))

(defun byte-compile-arglist-signature-string (signature)
  (cond ((null (cdr signature))
         (format "%d+" (car signature)))
        ((= (car signature) (cdr signature))
         (format "%d" (car signature)))
        (t (format "%d-%d" (car signature) (cdr signature)))))

(defun byte-compile-function-warn (f nargs def)
  (byte-compile-set-symbol-position f)
  (when (get f 'byte-obsolete-info)
    (byte-compile-warn-obsolete f))

  ;; Check to see if the function will be available at runtime
  ;; and/or remember its arity if it's unknown.
  (or (and (or def (fboundp f))         ; might be a subr or autoload.
           (not (memq f byte-compile-noruntime-functions)))
      (eq f byte-compile-current-form)  ; ## This doesn't work
                                        ; with recursion.
      ;; It's a currently-undefined function.
      ;; Remember number of args in call.
      (let ((cons (assq f byte-compile-unresolved-functions)))
        (if cons
            (or (memq nargs (cdr cons))
                (push nargs (cdr cons)))
          (push (list f nargs)
                byte-compile-unresolved-functions)))))

;; Warn if the form is calling a function with the wrong number of arguments.
(defun byte-compile-callargs-warn (form)
  (let* ((def (or (byte-compile-fdefinition (car form) nil)
                  (byte-compile-fdefinition (car form) t)))
         (sig (if (and def (not (eq def t)))
                  (progn
                    (and (eq (car-safe def) 'macro)
                         (eq (car-safe (cdr-safe def)) 'lambda)
                         (setq def (cdr def)))
                    (byte-compile-arglist-signature
                     (if (memq (car-safe def) '(declared lambda))
                         (nth 1 def)
                       (if (byte-code-function-p def)
                           (aref def 0)
                         '(&rest def)))))
                (if (subrp (symbol-function (car form)))
                    (subr-arity (symbol-function (car form))))))
         (ncall (length (cdr form))))
    ;; Check many or unevalled from subr-arity.
    (if (and (cdr-safe sig)
             (not (numberp (cdr sig))))
        (setcdr sig nil))
    (if sig
        (when (or (< ncall (car sig))
                (and (cdr sig) (> ncall (cdr sig))))
          (byte-compile-set-symbol-position (car form))
          (byte-compile-warn
           "%s called with %d argument%s, but %s %s"
           (car form) ncall
           (if (= 1 ncall) "" "s")
           (if (< ncall (car sig))
               "requires"
             "accepts only")
           (byte-compile-arglist-signature-string sig))))
    (byte-compile-format-warn form)
    (byte-compile-function-warn (car form) (length (cdr form)) def)))

(defun byte-compile-format-warn (form)
  "Warn if FORM is `format'-like with inconsistent args.
Applies if head of FORM is a symbol with non-nil property
`byte-compile-format-like' and first arg is a constant string.
Then check the number of format fields matches the number of
extra args."
  (when (and (symbolp (car form))
             (stringp (nth 1 form))
             (get (car form) 'byte-compile-format-like))
    (let ((nfields (with-temp-buffer
                     (insert (nth 1 form))
                     (goto-char (point-min))
                     (let ((n 0))
                       (while (re-search-forward "%." nil t)
                         (unless (eq ?% (char-after (1+ (match-beginning 0))))
                           (setq n (1+ n))))
                       n)))
          (nargs (- (length form) 2)))
      (unless (= nargs nfields)
        (byte-compile-warn
         "`%s' called with %d args to fill %d format field(s)" (car form)
         nargs nfields)))))

(dolist (elt '(format message error))
  (put elt 'byte-compile-format-like t))

;; Warn if a custom definition fails to specify :group, or :type.
(defun byte-compile-nogroup-warn (form)
  (let ((keyword-args (cdr (cdr (cdr (cdr form)))))
        (name (cadr form)))
    (when (eq (car-safe name) 'quote)
      (or (not (eq (car form) 'custom-declare-variable))
          (plist-get keyword-args :type)
          (byte-compile-warn
           "defcustom for `%s' fails to specify type" (cadr name)))
      (if (and (memq (car form) '(custom-declare-face custom-declare-variable))
               byte-compile-current-group)
          ;; The group will be provided implicitly.
          nil
        (or (and (eq (car form) 'custom-declare-group)
                 (equal name ''emacs))
            (plist-get keyword-args :group)
            (byte-compile-warn
             "%s for `%s' fails to specify containing group"
             (cdr (assq (car form)
                        '((custom-declare-group . defgroup)
                          (custom-declare-face . defface)
                          (custom-declare-variable . defcustom))))
             (cadr name)))
        ;; Update the current group, if needed.
        (if (and byte-compile-current-file ;Only when compiling a whole file.
                 (eq (car form) 'custom-declare-group))
            (setq byte-compile-current-group (cadr name)))))))

;; Warn if the function or macro is being redefined with a different
;; number of arguments.
(defun byte-compile-arglist-warn (name arglist macrop)
  ;; This is the first definition.  See if previous calls are compatible.
  (let ((calls (assq name byte-compile-unresolved-functions))
        nums sig min max)
    (when (and calls macrop)
      (byte-compile-warn "macro `%s' defined too late" name))
    (setq byte-compile-unresolved-functions
          (delq calls byte-compile-unresolved-functions))
    (setq calls (delq t calls))      ;Ignore higher-order uses of the function.
    (when (cdr calls)
      (when (and (symbolp name)
                 (eq (function-get name 'byte-optimizer)
                     'byte-compile-inline-expand))
        (byte-compile-warn "defsubst `%s' was used before it was defined"
                           name))
      (setq sig (byte-compile-arglist-signature arglist)
            nums (sort (copy-sequence (cdr calls)) (function <))
            min (car nums)
            max (car (nreverse nums)))
      (when (or (< min (car sig))
                (and (cdr sig) (> max (cdr sig))))
        (byte-compile-set-symbol-position name)
        (byte-compile-warn
         "%s being defined to take %s%s, but was previously called with %s"
         name
         (byte-compile-arglist-signature-string sig)
         (if (equal sig '(1 . 1)) " arg" " args")
         (byte-compile-arglist-signature-string (cons min max))))))
  (let* ((old (byte-compile-fdefinition name macrop))
         (initial (and macrop
                       (cdr (assq name
                                  byte-compile-initial-macro-environment)))))
    ;; Assumes an element of b-c-i-macro-env that is a symbol points
    ;; to a defined function.  (Bug#8646)
    (and initial (symbolp initial)
         (setq old (byte-compile-fdefinition initial nil)))
    (when (and old (not (eq old t)))
      (and (eq 'macro (car-safe old))
           (eq 'lambda (car-safe (cdr-safe old)))
           (setq old (cdr old)))
      (let ((sig1 (byte-compile-arglist-signature
                   (pcase old
                     (`(lambda ,args . ,_) args)
                     (`(closure ,_ ,args . ,_) args)
                     ((pred byte-code-function-p) (aref old 0))
                     (_ '(&rest def)))))
            (sig2 (byte-compile-arglist-signature arglist)))
        (unless (byte-compile-arglist-signatures-congruent-p sig1 sig2)
          (byte-compile-set-symbol-position name)
          (byte-compile-warn
           "%s %s used to take %s %s, now takes %s"
           (if macrop "macro" "function")
           name
           (byte-compile-arglist-signature-string sig1)
           (if (equal sig1 '(1 . 1)) "argument" "arguments")
           (byte-compile-arglist-signature-string sig2)))))))

(defvar byte-compile-cl-functions nil
  "List of functions defined in CL.")

;; Can't just add this to cl-load-hook, because that runs just before
;; the forms from cl.el get added to load-history.
(defun byte-compile-find-cl-functions ()
  (unless byte-compile-cl-functions
    (dolist (elt load-history)
      (and (byte-compile-cl-file-p (car elt))
           (dolist (e (cdr elt))
             ;; Includes the cl-foo functions that cl autoloads.
             (when (memq (car-safe e) '(autoload defun))
               (push (cdr e) byte-compile-cl-functions)))))))

(defun byte-compile-cl-warn (form)
  "Warn if FORM is a call of a function from the CL package."
  (let ((func (car-safe form)))
    (if (and byte-compile-cl-functions
             (memq func byte-compile-cl-functions)
             ;; Aliases which won't have been expanded at this point.
             ;; These aren't all aliases of subrs, so not trivial to
             ;; avoid hardwiring the list.
             (not (memq func
                        '(cl--block-wrapper cl--block-throw
                          multiple-value-call nth-value
                          copy-seq first second rest endp cl-member
                          ;; These are included in generated code
                          ;; that can't be called except at compile time
                          ;; or unless cl is loaded anyway.
                          cl--defsubst-expand cl-struct-setf-expander
                          ;; These would sometimes be warned about
                          ;; but such warnings are never useful,
                          ;; so don't warn about them.
                          macroexpand
                          cl--compiling-file))))
        (byte-compile-warn "function `%s' from cl package called at runtime"
                           func)))
  form)

(defun byte-compile-print-syms (str1 strn syms)
  (when syms
    (byte-compile-set-symbol-position (car syms) t))
  (cond ((and (cdr syms) (not noninteractive))
         (let* ((str strn)
                (L (length str))
                s)
           (while syms
             (setq s (symbol-name (pop syms))
                   L (+ L (length s) 2))
             (if (< L (1- fill-column))
                 (setq str (concat str " " s (and syms ",")))
               (setq str (concat str "\n    " s (and syms ","))
                     L (+ (length s) 4))))
           (byte-compile-warn "%s" str)))
        ((cdr syms)
         (byte-compile-warn "%s %s"
                            strn
                            (mapconcat #'symbol-name syms ", ")))

        (syms
         (byte-compile-warn str1 (car syms)))))

;; If we have compiled any calls to functions which are not known to be
;; defined, issue a warning enumerating them.
;; `unresolved' in the list `byte-compile-warnings' disables this.
(defun byte-compile-warn-about-unresolved-functions ()
  (when (byte-compile-warning-enabled-p 'unresolved)
    (let ((byte-compile-current-form :end)
          (noruntime nil)
          (unresolved nil))
      ;; Separate the functions that will not be available at runtime
      ;; from the truly unresolved ones.
      (dolist (f byte-compile-unresolved-functions)
        (setq f (car f))
        (when (not (memq f byte-compile-new-defuns))
          (if (fboundp f) (push f noruntime) (push f unresolved))))
      ;; Complain about the no-run-time functions
      (byte-compile-print-syms
       "the function `%s' might not be defined at runtime."
       "the following functions might not be defined at runtime:"
       noruntime)
      ;; Complain about the unresolved functions
      (byte-compile-print-syms
       "the function `%s' is not known to be defined."
       "the following functions are not known to be defined:"
       unresolved)))
  nil)

\f
;; Dynamically bound in byte-compile-from-buffer.
;; NB also used in cl.el and cl-macs.el.
(defvar byte-compile--outbuffer)

(defmacro byte-compile-close-variables (&rest body)
  (declare (debug t))
  `(let (;;
         ;; Close over these variables to encapsulate the
         ;; compilation state
         ;;
         (byte-compile-macro-environment
          ;; Copy it because the compiler may patch into the
          ;; macroenvironment.
          (copy-alist byte-compile-initial-macro-environment))
         (byte-compile--outbuffer nil)
         (byte-compile-function-environment nil)
         (byte-compile-bound-variables nil)
         (byte-compile-lexical-variables nil)
         (byte-compile-const-variables nil)
         (byte-compile-free-references nil)
         (byte-compile-free-assignments nil)
         ;;
         ;; Close over these variables so that `byte-compiler-options'
         ;; can change them on a per-file basis.
         ;;
         (byte-compile-verbose byte-compile-verbose)
         (byte-optimize byte-optimize)
         (byte-compile-dynamic byte-compile-dynamic)
         (byte-compile-dynamic-docstrings
          byte-compile-dynamic-docstrings)
         ;;             (byte-compile-generate-emacs19-bytecodes
         ;;              byte-compile-generate-emacs19-bytecodes)
         (byte-compile-warnings byte-compile-warnings)
         )
     ,@body))

(defmacro displaying-byte-compile-warnings (&rest body)
  (declare (debug t))
  `(let* ((--displaying-byte-compile-warnings-fn (lambda () ,@body))
          (warning-series-started
           (and (markerp warning-series)
                (eq (marker-buffer warning-series)
                    (get-buffer byte-compile-log-buffer)))))
     (byte-compile-find-cl-functions)
     (if (or (eq warning-series 'byte-compile-warning-series)
             warning-series-started)
         ;; warning-series does come from compilation,
         ;; so don't bind it, but maybe do set it.
         (let (tem)
           ;; Log the file name.  Record position of that text.
           (setq tem (byte-compile-log-file))
           (unless warning-series-started
             (setq warning-series (or tem 'byte-compile-warning-series)))
           (if byte-compile-debug
               (funcall --displaying-byte-compile-warnings-fn)
             (condition-case error-info
                 (funcall --displaying-byte-compile-warnings-fn)
               (error (byte-compile-report-error error-info)))))
       ;; warning-series does not come from compilation, so bind it.
       (let ((warning-series
              ;; Log the file name.  Record position of that text.
              (or (byte-compile-log-file) 'byte-compile-warning-series)))
         (if byte-compile-debug
             (funcall --displaying-byte-compile-warnings-fn)
           (condition-case error-info
               (funcall --displaying-byte-compile-warnings-fn)
             (error (byte-compile-report-error error-info))))))))
\f
;;;###autoload
(defun byte-force-recompile (directory)
  "Recompile every `.el' file in DIRECTORY that already has a `.elc' file.
Files in subdirectories of DIRECTORY are processed also."
  (interactive "DByte force recompile (directory): ")
  (byte-recompile-directory directory nil t))

;;;###autoload
(defun byte-recompile-directory (directory &optional arg force)
  "Recompile every `.el' file in DIRECTORY that needs recompilation.
This happens when a `.elc' file exists but is older than the `.el' file.
Files in subdirectories of DIRECTORY are processed also.

If the `.elc' file does not exist, normally this function *does not*
compile the corresponding `.el' file.  However, if the prefix argument
ARG is 0, that means do compile all those files.  A nonzero
ARG means ask the user, for each such `.el' file, whether to
compile it.  A nonzero ARG also means ask about each subdirectory
before scanning it.

If the third argument FORCE is non-nil, recompile every `.el' file
that already has a `.elc' file."
  (interactive "DByte recompile directory: \nP")
  (if arg (setq arg (prefix-numeric-value arg)))
  (if noninteractive
      nil
    (save-some-buffers)
    (force-mode-line-update))
  (with-current-buffer (get-buffer-create byte-compile-log-buffer)
    (setq default-directory (expand-file-name directory))
    ;; compilation-mode copies value of default-directory.
    (unless (eq major-mode 'compilation-mode)
      (compilation-mode))
    (let ((directories (list default-directory))
          (default-directory default-directory)
          (skip-count 0)
          (fail-count 0)
          (file-count 0)
          (dir-count 0)
          last-dir)
      (displaying-byte-compile-warnings
       (while directories
         (setq directory (car directories))
         (message "Checking %s..." directory)
         (dolist (file (directory-files directory))
           (let ((source (expand-file-name file directory)))
             (if (file-directory-p source)
                 (and (not (member file '("RCS" "CVS")))
                      (not (eq ?\. (aref file 0)))
                      (not (file-symlink-p source))
                      ;; This file is a subdirectory.  Handle them differently.
                      (or (null arg) (eq 0 arg)
                          (y-or-n-p (concat "Check " source "? ")))
                      (setq directories (nconc directories (list source))))
               ;; It is an ordinary file.  Decide whether to compile it.
               (if (and (string-match emacs-lisp-file-regexp source)
                        ;; The next 2 tests avoid compiling lock files
                        (file-readable-p source)
                        (not (string-match "\\`\\.#" file))
                        (not (auto-save-file-name-p source))
                        (not (string-equal dir-locals-file
                                           (file-name-nondirectory source))))
                   (progn (cl-incf
                           (pcase (byte-recompile-file source force arg)
                             (`no-byte-compile skip-count)
                             (`t file-count)
                             (_ fail-count)))
                          (or noninteractive
                              (message "Checking %s..." directory))
                          (if (not (eq last-dir directory))
                              (setq last-dir directory
                                    dir-count (1+ dir-count)))
                          )))))
         (setq directories (cdr directories))))
      (message "Done (Total of %d file%s compiled%s%s%s)"
               file-count (if (= file-count 1) "" "s")
               (if (> fail-count 0) (format ", %d failed" fail-count) "")
               (if (> skip-count 0) (format ", %d skipped" skip-count) "")
               (if (> dir-count 1)
                   (format " in %d directories" dir-count) "")))))

(defvar no-byte-compile nil
  "Non-nil to prevent byte-compiling of Emacs Lisp code.
This is normally set in local file variables at the end of the elisp file:

\;; Local Variables:\n;; no-byte-compile: t\n;; End: ") ;Backslash for compile-main.
;;;###autoload(put 'no-byte-compile 'safe-local-variable 'booleanp)

(defun byte-recompile-file (filename &optional force arg load)
  "Recompile FILENAME file if it needs recompilation.
This happens when its `.elc' file is older than itself.

If the `.elc' file exists and is up-to-date, normally this function
*does not* compile FILENAME.  If the prefix argument FORCE is non-nil,
however, it compiles FILENAME even if the destination already
exists and is up-to-date.

If the `.elc' file does not exist, normally this function *does not*
compile FILENAME.  If optional argument ARG is 0, it compiles
the input file even if the `.elc' file does not exist.
Any other non-nil value of ARG means to ask the user.

If optional argument LOAD is non-nil, loads the file after compiling.

If compilation is needed, this functions returns the result of
`byte-compile-file'; otherwise it returns `no-byte-compile'."
  (interactive
   (let ((file buffer-file-name)
         (file-name nil)
         (file-dir nil))
     (and file
          (derived-mode-p 'emacs-lisp-mode)
          (setq file-name (file-name-nondirectory file)
                file-dir (file-name-directory file)))
     (list (read-file-name (if current-prefix-arg
                               "Byte compile file: "
                             "Byte recompile file: ")
                           file-dir file-name nil)
           current-prefix-arg)))
  (let ((dest (byte-compile-dest-file filename))
        ;; Expand now so we get the current buffer's defaults
        (filename (expand-file-name filename)))
    (if (if (file-exists-p dest)
            ;; File was already compiled
            ;; Compile if forced to, or filename newer
            (or force
                (file-newer-than-file-p filename dest))
          (and arg
               (or (eq 0 arg)
                   (y-or-n-p (concat "Compile "
                                     filename "? ")))))
        (progn
          (if (and noninteractive (not byte-compile-verbose))
              (message "Compiling %s..." filename))
          (byte-compile-file filename load))
      (when load
        (load (if (file-exists-p dest) dest filename)))
      'no-byte-compile)))

(defvar byte-compile-level 0            ; bug#13787
  "Depth of a recursive byte compilation.")

;;;###autoload
(defun byte-compile-file (filename &optional load)
  "Compile a file of Lisp code named FILENAME into a file of byte code.
The output file's name is generated by passing FILENAME to the
function `byte-compile-dest-file' (which see).
With prefix arg (noninteractively: 2nd arg), LOAD the file after compiling.
The value is non-nil if there were no errors, nil if errors."
;;  (interactive "fByte compile file: \nP")
  (interactive
   (let ((file buffer-file-name)
         (file-dir nil))
     (and file
          (derived-mode-p 'emacs-lisp-mode)
          (setq file-dir (file-name-directory file)))
     (list (read-file-name (if current-prefix-arg
                               "Byte compile and load file: "
                             "Byte compile file: ")
                           file-dir buffer-file-name nil)
           current-prefix-arg)))
  ;; Expand now so we get the current buffer's defaults
  (setq filename (expand-file-name filename))

  ;; If we're compiling a file that's in a buffer and is modified, offer
  ;; to save it first.
  (or noninteractive
      (let ((b (get-file-buffer (expand-file-name filename))))
        (if (and b (buffer-modified-p b)
                 (y-or-n-p (format "Save buffer %s first? " (buffer-name b))))
            (with-current-buffer b (save-buffer)))))

  ;; Force logging of the file name for each file compiled.
  (setq byte-compile-last-logged-file nil)
  (let ((byte-compile-current-file filename)
        (byte-compile-current-group nil)
        (set-auto-coding-for-load t)
        target-file input-buffer output-buffer
        byte-compile-dest-file)
    (setq target-file (byte-compile-dest-file filename))
    (setq byte-compile-dest-file target-file)
    (with-current-buffer
        ;; It would be cleaner to use a temp buffer, but if there was
        ;; an error, we leave this buffer around for diagnostics.
        ;; Its name is documented in the lispref.
        (setq input-buffer (get-buffer-create
                            (concat " *Compiler Input*"
                                    (if (zerop byte-compile-level) ""
                                      (format "-%s" byte-compile-level)))))
      (erase-buffer)
      (setq buffer-file-coding-system nil)
      ;; Always compile an Emacs Lisp file as multibyte
      ;; unless the file itself forces unibyte with -*-coding: raw-text;-*-
      (set-buffer-multibyte t)
      (insert-file-contents filename)
      ;; Mimic the way after-insert-file-set-coding can make the
      ;; buffer unibyte when visiting this file.
      (when (or (eq last-coding-system-used 'no-conversion)
                (eq (coding-system-type last-coding-system-used) 5))
        ;; For coding systems no-conversion and raw-text...,
        ;; edit the buffer as unibyte.
        (set-buffer-multibyte nil))
      ;; Run hooks including the uncompression hook.
      ;; If they change the file name, then change it for the output also.
      (let ((buffer-file-name filename)
            (dmm (default-value 'major-mode))
            ;; Ignore unsafe local variables.
            ;; We only care about a few of them for our purposes.
            (enable-local-variables :safe)
            (enable-local-eval nil))
        (unwind-protect
            (progn
              (setq-default major-mode 'emacs-lisp-mode)
              ;; Arg of t means don't alter enable-local-variables.
              (delay-mode-hooks (normal-mode t)))
          (setq-default major-mode dmm))
        ;; There may be a file local variable setting (bug#10419).
        (setq buffer-read-only nil
              filename buffer-file-name))
      ;; Don't inherit lexical-binding from caller (bug#12938).
      (unless (local-variable-p 'lexical-binding)
        (setq-local lexical-binding nil))
      ;; Set the default directory, in case an eval-when-compile uses it.
      (setq default-directory (file-name-directory filename)))
    ;; Check if the file's local variables explicitly specify not to
    ;; compile this file.
    (if (with-current-buffer input-buffer no-byte-compile)
        (progn
          ;; (message "%s not compiled because of `no-byte-compile: %s'"
          ;;       (byte-compile-abbreviate-file filename)
          ;;       (with-current-buffer input-buffer no-byte-compile))
          (when (file-exists-p target-file)
            (message "%s deleted because of `no-byte-compile: %s'"
                     (byte-compile-abbreviate-file target-file)
                     (buffer-local-value 'no-byte-compile input-buffer))
            (condition-case nil (delete-file target-file) (error nil)))
          ;; We successfully didn't compile this file.
          'no-byte-compile)
      (when byte-compile-verbose
        (message "Compiling %s..." filename))
      (setq byte-compiler-error-flag nil)
      ;; It is important that input-buffer not be current at this call,
      ;; so that the value of point set in input-buffer
      ;; within byte-compile-from-buffer lingers in that buffer.
      (setq output-buffer
            (save-current-buffer
              (let ((byte-compile-level (1+ byte-compile-level)))
                (byte-compile-from-buffer input-buffer))))
      (if byte-compiler-error-flag
          nil
        (when byte-compile-verbose
          (message "Compiling %s...done" filename))
        (kill-buffer input-buffer)
        (with-current-buffer output-buffer
          (goto-char (point-max))
          (insert "\n")                 ; aaah, unix.
          (if (file-writable-p target-file)
              ;; We must disable any code conversion here.
              (let* ((coding-system-for-write 'no-conversion)
                     ;; Write to a tempfile so that if another Emacs
                     ;; process is trying to load target-file (eg in a
                     ;; parallel bootstrap), it does not risk getting a
                     ;; half-finished file.  (Bug#4196)
                     (tempfile (make-temp-name target-file))
                     (kill-emacs-hook
                      (cons (lambda () (ignore-errors (delete-file tempfile)))
                            kill-emacs-hook)))
                (write-region (point-min) (point-max) tempfile nil 1)
                ;; This has the intentional side effect that any
                ;; hard-links to target-file continue to
                ;; point to the old file (this makes it possible
                ;; for installed files to share disk space with
                ;; the build tree, without causing problems when
                ;; emacs-lisp files in the build tree are
                ;; recompiled).  Previously this was accomplished by
                ;; deleting target-file before writing it.
                (rename-file tempfile target-file t)
                (or noninteractive (message "Wrote %s" target-file)))
            ;; This is just to give a better error message than write-region
            (let ((exists (file-exists-p target-file)))
              (signal (if exists 'file-error 'file-missing)
                      (list "Opening output file"
                            (if exists
                                "Cannot overwrite file"
                              "Directory not writable or nonexistent")
                            target-file))))
          (kill-buffer (current-buffer)))
        (if (and byte-compile-generate-call-tree
                 (or (eq t byte-compile-generate-call-tree)
                     (y-or-n-p (format "Report call tree for %s? "
                                       filename))))
            (save-excursion
              (display-call-tree filename)))
        (if load
            (load target-file))
        t))))

;;; compiling a single function
;;;###autoload
(defun compile-defun (&optional arg)
  "Compile and evaluate the current top-level form.
Print the result in the echo area.
With argument ARG, insert value in current buffer after the form."
  (interactive "P")
  (save-excursion
    (end-of-defun)
    (beginning-of-defun)
    (let* ((byte-compile-current-file nil)
           (byte-compile-current-buffer (current-buffer))
           (byte-compile-read-position (point))
           (byte-compile-last-position byte-compile-read-position)
           (byte-compile-last-warned-form 'nothing)
           (value (eval
                   (let ((read-with-symbol-positions (current-buffer))
                         (read-symbol-positions-list nil))
                     (displaying-byte-compile-warnings
                      (byte-compile-sexp
                       (eval-sexp-add-defvars
                        (read (current-buffer))
                        byte-compile-read-position))))
                   lexical-binding)))
      (cond (arg
             (message "Compiling from buffer... done.")
             (prin1 value (current-buffer))
             (insert "\n"))
            ((message "%s" (prin1-to-string value)))))))

(defun byte-compile-from-buffer (inbuffer)
  (let ((byte-compile-current-buffer inbuffer)
        (byte-compile-read-position nil)
        (byte-compile-last-position nil)
        ;; Prevent truncation of flonums and lists as we read and print them
        (float-output-format nil)
        (case-fold-search nil)
        (print-length nil)
        (print-level nil)
        ;; Prevent edebug from interfering when we compile
        ;; and put the output into a file.
;;      (edebug-all-defs nil)
;;      (edebug-all-forms nil)
        ;; Simulate entry to byte-compile-top-level
        (byte-compile-jump-tables nil)
        (byte-compile-constants nil)
        (byte-compile-variables nil)
        (byte-compile-tag-number 0)
        (byte-compile-depth 0)
        (byte-compile-maxdepth 0)
        (byte-compile-output nil)
        ;; This allows us to get the positions of symbols read; it's
        ;; new in Emacs 22.1.
        (read-with-symbol-positions inbuffer)
        (read-symbol-positions-list nil)
        ;;        #### This is bound in b-c-close-variables.
        ;;        (byte-compile-warnings byte-compile-warnings)
        )
    (byte-compile-close-variables
     (with-current-buffer
         (setq byte-compile--outbuffer
               (get-buffer-create
                (concat " *Compiler Output*"
                        (if (<= byte-compile-level 1) ""
                          (format "-%s" (1- byte-compile-level))))))
       (set-buffer-multibyte t)
       (erase-buffer)
       ;;        (emacs-lisp-mode)
       (setq case-fold-search nil))
     (displaying-byte-compile-warnings
      (with-current-buffer inbuffer
        (and byte-compile-current-file
             (byte-compile-insert-header byte-compile-current-file
                                         byte-compile--outbuffer))
        (goto-char (point-min))
        ;; Should we always do this?  When calling multiple files, it
        ;; would be useful to delay this warning until all have been
        ;; compiled.  A: Yes!  b-c-u-f might contain dross from a
        ;; previous byte-compile.
        (setq byte-compile-unresolved-functions nil)
        (setq byte-compile-noruntime-functions nil)
        (setq byte-compile-new-defuns nil)

        ;; Compile the forms from the input buffer.
        (while (progn
                 (while (progn (skip-chars-forward " \t\n\^l")
                               (= (following-char) ?\;))
                   (forward-line 1))
                 (not (eobp)))
          (setq byte-compile-read-position (point)
                byte-compile-last-position byte-compile-read-position)
          (let* ((old-style-backquotes nil)
                 (form (read inbuffer)))
            ;; Warn about the use of old-style backquotes.
            (when old-style-backquotes
              (byte-compile-warn "!! The file uses old-style backquotes !!
This functionality has been obsolete for more than 10 years already
and will be removed soon.  See (elisp)Backquote in the manual."))
            (byte-compile-toplevel-file-form form)))
        ;; Compile pending forms at end of file.
        (byte-compile-flush-pending)
        ;; Make warnings about unresolved functions
        ;; give the end of the file as their position.
        (setq byte-compile-last-position (point-max))
        (byte-compile-warn-about-unresolved-functions))
      ;; Fix up the header at the front of the output
      ;; if the buffer contains multibyte characters.
      (and byte-compile-current-file
           (with-current-buffer byte-compile--outbuffer
             (byte-compile-fix-header byte-compile-current-file))))
     byte-compile--outbuffer)))

(defun byte-compile-fix-header (_filename)
  "If the current buffer has any multibyte characters, insert a version test."
  (when (< (point-max) (position-bytes (point-max)))
    (goto-char (point-min))
    ;; Find the comment that describes the version condition.
    (search-forward "\n;;; This file uses")
    (narrow-to-region (line-beginning-position) (point-max))
    ;; Find the first line of ballast semicolons.
    (search-forward ";;;;;;;;;;")
    (beginning-of-line)
    (narrow-to-region (point-min) (point))
    (let ((old-header-end (point))
          (minimum-version "23")
          delta)
      (delete-region (point-min) (point-max))
      (insert
       ";;; This file contains utf-8 non-ASCII characters,\n"
       ";;; and so cannot be loaded into Emacs 22 or earlier.\n"
       ;; Have to check if emacs-version is bound so that this works
       ;; in files loaded early in loadup.el.
       "(and (boundp 'emacs-version)\n"
       ;; If there is a name at the end of emacs-version,
       ;; don't try to check the version number.
       "     (< (aref emacs-version (1- (length emacs-version))) ?A)\n"
       (format "     (string-lessp emacs-version \"%s\")\n" minimum-version)
       ;; Because the header must fit in a fixed width, we cannot
       ;; insert arbitrary-length file names (Bug#11585).
       "     (error \"`%s' was compiled for "
       (format "Emacs %s or later\" #$))\n\n" minimum-version))
      ;; Now compensate for any change in size, to make sure all
      ;; positions in the file remain valid.
      (setq delta (- (point-max) old-header-end))
      (goto-char (point-max))
      (widen)
      (delete-char delta))))

(defun byte-compile-insert-header (_filename outbuffer)
  "Insert a header at the start of OUTBUFFER.
Call from the source buffer."
  (let ((dynamic-docstrings byte-compile-dynamic-docstrings)
        (dynamic byte-compile-dynamic)
        (optimize byte-optimize))
    (with-current-buffer outbuffer
      (goto-char (point-min))
      ;; The magic number of .elc files is ";ELC", or 0x3B454C43.  After
      ;; that is the file-format version number (18, 19, 20, or 23) as a
      ;; byte, followed by some nulls.  The primary motivation for doing
      ;; this is to get some binary characters up in the first line of
      ;; the file so that `diff' will simply say "Binary files differ"
      ;; instead of actually doing a diff of two .elc files.  An extra
      ;; benefit is that you can add this to /etc/magic:
      ;; 0      string          ;ELC            GNU Emacs Lisp compiled file,
      ;; >4     byte            x               version %d
      (insert
       ";ELC" 23 "\000\000\000\n"
       ";;; Compiled\n"
       ";;; in Emacs version " emacs-version "\n"
       ";;; with"
       (cond
        ((eq optimize 'source) " source-level optimization only")
        ((eq optimize 'byte) " byte-level optimization only")
        (optimize " all optimizations")
        (t "out optimization"))
       ".\n"
       (if dynamic ";;; Function definitions are lazy-loaded.\n"
         "")
       "\n;;; This file uses "
       (if dynamic-docstrings
           "dynamic docstrings, first added in Emacs 19.29"
         "opcodes that do not exist in Emacs 18")
       ".\n\n"
       ;; Note that byte-compile-fix-header may change this.
       ";;; This file does not contain utf-8 non-ASCII characters,\n"
       ";;; and so can be loaded in Emacs versions earlier than 23.\n\n"
       ;; Insert semicolons as ballast, so that byte-compile-fix-header
       ;; can delete them so as to keep the buffer positions
       ;; constant for the actual compiled code.
       ";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;\n"
       ";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;\n\n"))))

(defun byte-compile-output-file-form (form)
  ;; Write the given form to the output buffer, being careful of docstrings
  ;; in defvar, defvaralias, defconst, autoload and
  ;; custom-declare-variable because make-docfile is so amazingly stupid.
  ;; defalias calls are output directly by byte-compile-file-form-defmumble;
  ;; it does not pay to first build the defalias in defmumble and then parse
  ;; it here.
  (let ((print-escape-newlines t)
        (print-length nil)
        (print-level nil)
        (print-quoted t)
        (print-gensym t)
        (print-circle                   ; Handle circular data structures.
         (not byte-compile-disable-print-circle)))
    (if (and (memq (car-safe form) '(defvar defvaralias defconst
                                      autoload custom-declare-variable))
             (stringp (nth 3 form)))
        (byte-compile-output-docform nil nil '("\n(" 3 ")") form nil
                                     (memq (car form)
                                           '(defvaralias autoload
                                              custom-declare-variable)))
      (princ "\n" byte-compile--outbuffer)
      (prin1 form byte-compile--outbuffer)
      nil)))

(defvar byte-compile--for-effect)

(defun byte-compile-output-docform (preface name info form specindex quoted)
  "Print a form with a doc string.  INFO is (prefix doc-index postfix).
If PREFACE and NAME are non-nil, print them too,
before INFO and the FORM but after the doc string itself.
If SPECINDEX is non-nil, it is the index in FORM
of the function bytecode string.  In that case,
we output that argument and the following argument
\(the constants vector) together, for lazy loading.
QUOTED says that we have to put a quote before the
list that represents a doc string reference.
`defvaralias', `autoload' and `custom-declare-variable' need that."
  ;; We need to examine byte-compile-dynamic-docstrings
  ;; in the input buffer (now current), not in the output buffer.
  (let ((dynamic-docstrings byte-compile-dynamic-docstrings))
    (with-current-buffer byte-compile--outbuffer
      (let (position)

        ;; Insert the doc string, and make it a comment with #@LENGTH.
        (and (>= (nth 1 info) 0)
             dynamic-docstrings
             (progn
               ;; Make the doc string start at beginning of line
               ;; for make-docfile's sake.
               (insert "\n")
               (setq position
                     (byte-compile-output-as-comment
                      (nth (nth 1 info) form) nil))
               ;; If the doc string starts with * (a user variable),
               ;; negate POSITION.
               (if (and (stringp (nth (nth 1 info) form))
                        (> (length (nth (nth 1 info) form)) 0)
                        (eq (aref (nth (nth 1 info) form) 0) ?*))
                   (setq position (- position)))))

        (let ((print-continuous-numbering t)
              print-number-table
              (index 0)
              ;; FIXME: The bindings below are only needed for when we're
              ;; called from ...-defmumble.
              (print-escape-newlines t)
              (print-length nil)
              (print-level nil)
              (print-quoted t)
              (print-gensym t)
              (print-circle             ; Handle circular data structures.
               (not byte-compile-disable-print-circle)))
          (if preface
              (progn
                ;; FIXME: We don't handle uninterned names correctly.
                ;; E.g. if cl-define-compiler-macro uses uninterned name we get:
                ;;    (defalias '#1=#:foo--cmacro #[514 ...])
                ;;    (put 'foo 'compiler-macro '#:foo--cmacro)
                (insert preface)
                (prin1 name byte-compile--outbuffer)))
          (insert (car info))
          (prin1 (car form) byte-compile--outbuffer)
          (while (setq form (cdr form))
            (setq index (1+ index))
            (insert " ")
            (cond ((and (numberp specindex) (= index specindex)
                        ;; Don't handle the definition dynamically
                        ;; if it refers (or might refer)
                        ;; to objects already output
                        ;; (for instance, gensyms in the arg list).
                        (let (non-nil)
                          (when (hash-table-p print-number-table)
                            (maphash (lambda (_k v) (if v (setq non-nil t)))
                                     print-number-table))
                          (not non-nil)))
                   ;; Output the byte code and constants specially
                   ;; for lazy dynamic loading.
                   (let ((position
                          (byte-compile-output-as-comment
                           (cons (car form) (nth 1 form))
                           t)))
                     (princ (format "(#$ . %d) nil" position)
                            byte-compile--outbuffer)
                     (setq form (cdr form))
                     (setq index (1+ index))))
                  ((= index (nth 1 info))
                   (if position
                       (princ (format (if quoted "'(#$ . %d)"  "(#$ . %d)")
                                      position)
                              byte-compile--outbuffer)
                     (let ((print-escape-newlines nil))
                       (goto-char (prog1 (1+ (point))
                                    (prin1 (car form)
                                           byte-compile--outbuffer)))
                       (insert "\\\n")
                       (goto-char (point-max)))))
                  (t
                   (prin1 (car form) byte-compile--outbuffer)))))
        (insert (nth 2 info)))))
  nil)

(defun byte-compile-keep-pending (form &optional handler)
  (if (memq byte-optimize '(t source))
      (setq form (byte-optimize-form form t)))
  (if handler
      (let ((byte-compile--for-effect t))
        ;; To avoid consing up monstrously large forms at load time, we split
        ;; the output regularly.
        (and (memq (car-safe form) '(fset defalias))
             (nthcdr 300 byte-compile-output)
             (byte-compile-flush-pending))
        (funcall handler form)
        (if byte-compile--for-effect
            (byte-compile-discard)))
    (byte-compile-form form t))
  nil)

(defun byte-compile-flush-pending ()
  (if byte-compile-output
      (let ((form (byte-compile-out-toplevel t 'file)))
        (cond ((eq (car-safe form) 'progn)
               (mapc 'byte-compile-output-file-form (cdr form)))
              (form
               (byte-compile-output-file-form form)))
        (setq byte-compile-constants nil
              byte-compile-variables nil
              byte-compile-depth 0
              byte-compile-maxdepth 0
              byte-compile-output nil
              byte-compile-jump-tables nil))))

(defvar byte-compile-force-lexical-warnings nil)

(defun byte-compile-preprocess (form &optional _for-effect)
  (setq form (macroexpand-all form byte-compile-macro-environment))
  ;; FIXME: We should run byte-optimize-form here, but it currently does not
  ;; recurse through all the code, so we'd have to fix this first.
  ;; Maybe a good fix would be to merge byte-optimize-form into
  ;; macroexpand-all.
  ;; (if (memq byte-optimize '(t source))
  ;;     (setq form (byte-optimize-form form for-effect)))
  (cond
   (lexical-binding (cconv-closure-convert form))
   (byte-compile-force-lexical-warnings (cconv-warnings-only form))
   (t form)))

;; byte-hunk-handlers cannot call this!
(defun byte-compile-toplevel-file-form (top-level-form)
  (byte-compile-recurse-toplevel
   top-level-form
   (lambda (form)
     (let ((byte-compile-current-form nil)) ; close over this for warnings.
       (byte-compile-file-form (byte-compile-preprocess form t))))))

;; byte-hunk-handlers can call this.
(defun byte-compile-file-form (form)
  (let (handler)
    (cond ((and (consp form)
                (symbolp (car form))
                (setq handler (get (car form) 'byte-hunk-handler)))
           (cond ((setq form (funcall handler form))
                  (byte-compile-flush-pending)
                  (byte-compile-output-file-form form))))
          (t
           (byte-compile-keep-pending form)))))

;; Functions and variables with doc strings must be output separately,
;; so make-docfile can recognize them.  Most other things can be output
;; as byte-code.

(put 'autoload 'byte-hunk-handler 'byte-compile-file-form-autoload)
(defun byte-compile-file-form-autoload (form)
  (and (let ((form form))
         (while (if (setq form (cdr form)) (macroexp-const-p (car form))))
         (null form))                        ;Constants only
       (memq (eval (nth 5 form)) '(t macro)) ;Macro
       (eval form))                          ;Define the autoload.
  ;; Avoid undefined function warnings for the autoload.
  (pcase (nth 1 form)
    (`',(and (pred symbolp) funsym)
     ;; Don't add it if it's already defined.  Otherwise, it might
     ;; hide the actual definition.  However, do remove any entry from
     ;; byte-compile-noruntime-functions, in case we have an autoload
     ;; of foo-func following an (eval-when-compile (require 'foo)).
     (unless (fboundp funsym)
       (push (cons funsym (cons 'autoload (cdr (cdr form))))
             byte-compile-function-environment))
     ;; If an autoload occurs _before_ the first call to a function,
     ;; byte-compile-callargs-warn does not add an entry to
     ;; byte-compile-unresolved-functions.  Here we mimic the logic
     ;; of byte-compile-callargs-warn so as not to warn if the
     ;; autoload comes _after_ the function call.
     ;; Alternatively, similar logic could go in
     ;; byte-compile-warn-about-unresolved-functions.
     (if (memq funsym byte-compile-noruntime-functions)
         (setq byte-compile-noruntime-functions
               (delq funsym byte-compile-noruntime-functions))
       (setq byte-compile-unresolved-functions
             (delq (assq funsym byte-compile-unresolved-functions)
                   byte-compile-unresolved-functions)))))
  (if (stringp (nth 3 form))
      form
    ;; No doc string, so we can compile this as a normal form.
    (byte-compile-keep-pending form 'byte-compile-normal-call)))

(put 'defvar   'byte-hunk-handler 'byte-compile-file-form-defvar)
(put 'defconst 'byte-hunk-handler 'byte-compile-file-form-defvar)

(defun byte-compile--declare-var (sym)
  (when (and (symbolp sym)
             (not (string-match "[-*/:$]" (symbol-name sym)))
             (byte-compile-warning-enabled-p 'lexical))
    (byte-compile-warn "global/dynamic var `%s' lacks a prefix"
                       sym))
  (when (memq sym byte-compile-lexical-variables)
    (setq byte-compile-lexical-variables
          (delq sym byte-compile-lexical-variables))
    (byte-compile-warn "Variable `%S' declared after its first use" sym))
  (push sym byte-compile-bound-variables))

(defun byte-compile-file-form-defvar (form)
  (let ((sym (nth 1 form)))
    (byte-compile--declare-var sym)
    (if (eq (car form) 'defconst)
        (push sym byte-compile-const-variables)))
  (if (and (null (cddr form))           ;No `value' provided.
           (eq (car form) 'defvar))     ;Just a declaration.
      nil
    (cond ((consp (nth 2 form))
           (setq form (copy-sequence form))
           (setcar (cdr (cdr form))
                   (byte-compile-top-level (nth 2 form) nil 'file))))
    form))

(put 'define-abbrev-table 'byte-hunk-handler
     'byte-compile-file-form-defvar-function)
(put 'defvaralias 'byte-hunk-handler 'byte-compile-file-form-defvar-function)

(defun byte-compile-file-form-defvar-function (form)
  (pcase-let (((or `',name (let name nil)) (nth 1 form)))
    (if name (byte-compile--declare-var name)))
  (byte-compile-keep-pending form))

(put 'custom-declare-variable 'byte-hunk-handler
     'byte-compile-file-form-custom-declare-variable)
(defun byte-compile-file-form-custom-declare-variable (form)
  (when (byte-compile-warning-enabled-p 'callargs)
    (byte-compile-nogroup-warn form))
  (byte-compile-file-form-defvar-function form))

(put 'require 'byte-hunk-handler 'byte-compile-file-form-require)
(defun byte-compile-file-form-require (form)
  (let ((args (mapcar 'eval (cdr form)))
        (hist-orig load-history)
        hist-new prov-cons)
    (apply 'require args)

    ;; Record the functions defined by the require in `byte-compile-new-defuns'.
    (setq hist-new load-history)
    (setq prov-cons (cons 'provide (car args)))
    (while (and hist-new
                (not (member prov-cons (car hist-new))))
      (setq hist-new (cdr hist-new)))
    (when hist-new
      (dolist (x (car hist-new))
        (when (and (consp x)
                   (memq (car x) '(defun t)))
          (push (cdr x) byte-compile-new-defuns))))

    (when (byte-compile-warning-enabled-p 'cl-functions)
      ;; Detect (require 'cl) in a way that works even if cl is already loaded.
      (if (member (car args) '("cl" cl))
          (progn
            (byte-compile-warn "cl package required at runtime")
            (byte-compile-disable-warning 'cl-functions))
        ;; We may have required something that causes cl to be loaded, eg
        ;; the uncompiled version of a file that requires cl when compiling.
        (setq hist-new load-history)
        (while (and (not byte-compile-cl-functions)
                    hist-new (not (eq hist-new hist-orig)))
          (and (byte-compile-cl-file-p (car (pop hist-new)))
               (byte-compile-find-cl-functions))))))
  (byte-compile-keep-pending form 'byte-compile-normal-call))

(put 'progn 'byte-hunk-handler 'byte-compile-file-form-progn)
(put 'prog1 'byte-hunk-handler 'byte-compile-file-form-progn)
(put 'prog2 'byte-hunk-handler 'byte-compile-file-form-progn)
(defun byte-compile-file-form-progn (form)
  (mapc 'byte-compile-file-form (cdr form))
  ;; Return nil so the forms are not output twice.
  nil)

(put 'with-no-warnings 'byte-hunk-handler
     'byte-compile-file-form-with-no-warnings)
(defun byte-compile-file-form-with-no-warnings (form)
  ;; cf byte-compile-file-form-progn.
  (let (byte-compile-warnings)
    (mapc 'byte-compile-file-form (cdr form))
    nil))

;; This handler is not necessary, but it makes the output from dont-compile
;; and similar macros cleaner.
(put 'eval 'byte-hunk-handler 'byte-compile-file-form-eval)
(defun byte-compile-file-form-eval (form)
  (if (eq (car-safe (nth 1 form)) 'quote)
      (nth 1 (nth 1 form))
    (byte-compile-keep-pending form)))

(defun byte-compile-file-form-defmumble (name macro arglist body rest)
  "Process a `defalias' for NAME.
If MACRO is non-nil, the definition is known to be a macro.
ARGLIST is the list of arguments, if it was recognized or t otherwise.
BODY of the definition, or t if not recognized.
Return non-nil if everything went as planned, or nil to imply that it decided
not to take responsibility for the actual compilation of the code."
  (let* ((this-kind (if macro 'byte-compile-macro-environment
                      'byte-compile-function-environment))
         (that-kind (if macro 'byte-compile-function-environment
                      'byte-compile-macro-environment))
         (this-one (assq name (symbol-value this-kind)))
         (that-one (assq name (symbol-value that-kind)))
         (byte-compile-current-form name)) ; For warnings.

    (byte-compile-set-symbol-position name)
    (push name byte-compile-new-defuns)
    ;; When a function or macro is defined, add it to the call tree so that
    ;; we can tell when functions are not used.
    (if byte-compile-generate-call-tree
        (or (assq name byte-compile-call-tree)
            (setq byte-compile-call-tree
                  (cons (list name nil nil) byte-compile-call-tree))))

    (if (byte-compile-warning-enabled-p 'redefine)
        (byte-compile-arglist-warn name arglist macro))

    (if byte-compile-verbose
        (message "Compiling %s... (%s)"
                 (or byte-compile-current-file "") name))
    (cond ((not (or macro (listp body)))
           ;; We do not know positively if the definition is a macro
           ;; or a function, so we shouldn't emit warnings.
           ;; This also silences "multiple definition" warnings for defmethods.
           nil)
          (that-one
           (if (and (byte-compile-warning-enabled-p 'redefine)
                    ;; Don't warn when compiling the stubs in byte-run...
                    (not (assq name byte-compile-initial-macro-environment)))
               (byte-compile-warn
                "`%s' defined multiple times, as both function and macro"
                name))
           (setcdr that-one nil))
          (this-one
           (when (and (byte-compile-warning-enabled-p 'redefine)
                      ;; Hack: Don't warn when compiling the magic internal
                      ;; byte-compiler macros in byte-run.el...
                      (not (assq name byte-compile-initial-macro-environment)))
             (byte-compile-warn "%s `%s' defined multiple times in this file"
                                (if macro "macro" "function")
                                name)))
          ((eq (car-safe (symbol-function name))
               (if macro 'lambda 'macro))
           (when (byte-compile-warning-enabled-p 'redefine)
             (byte-compile-warn "%s `%s' being redefined as a %s"
                                (if macro "function" "macro")
                                name
                                (if macro "macro" "function")))
           ;; Shadow existing definition.
           (set this-kind
                (cons (cons name nil)
                      (symbol-value this-kind))))
          )

    (when (and (listp body)
               (stringp (car body))
               (symbolp (car-safe (cdr-safe body)))
               (car-safe (cdr-safe body))
               (stringp (car-safe (cdr-safe (cdr-safe body)))))
      ;; FIXME: We've done that already just above, so this looks wrong!
      ;;(byte-compile-set-symbol-position name)
      (byte-compile-warn "probable `\"' without `\\' in doc string of %s"
                         name))

    (if (not (listp body))
        ;; The precise definition requires evaluation to find out, so it
        ;; will only be known at runtime.
        ;; For a macro, that means we can't use that macro in the same file.
        (progn
          (unless macro
            (push (cons name (if (listp arglist) `(declared ,arglist) t))
                  byte-compile-function-environment))
          ;; Tell the caller that we didn't compile it yet.
          nil)

      (let* ((code (byte-compile-lambda (cons arglist body) t)))
        (if this-one
            ;; A definition in b-c-initial-m-e should always take precedence
            ;; during compilation, so don't let it be redefined.  (Bug#8647)
            (or (and macro
                     (assq name byte-compile-initial-macro-environment))
                (setcdr this-one code))
          (set this-kind
               (cons (cons name code)
                     (symbol-value this-kind))))

        (if rest
            ;; There are additional args to `defalias' (like maybe a docstring)
            ;; that the code below can't handle: punt!
            nil
          ;; Otherwise, we have a bona-fide defun/defmacro definition, and use
          ;; special code to allow dynamic docstrings and byte-code.
          (byte-compile-flush-pending)
          (let ((index
                 ;; If there's no doc string, provide -1 as the "doc string
                 ;; index" so that no element will be treated as a doc string.
                 (if (not (stringp (car body))) -1 4)))
            ;; Output the form by hand, that's much simpler than having
            ;; b-c-output-file-form analyze the defalias.
            (byte-compile-output-docform
             "\n(defalias '"
             name
             (if macro `(" '(macro . #[" ,index "])") `(" #[" ,index "]"))
             (append code nil)          ; Turn byte-code-function-p into list.
             (and (atom code) byte-compile-dynamic
                  1)
             nil))
          (princ ")" byte-compile--outbuffer)
          t)))))

(defun byte-compile-output-as-comment (exp quoted)
  "Print Lisp object EXP in the output file, inside a comment,
and return the file (byte) position it will have.
If QUOTED is non-nil, print with quoting; otherwise, print without quoting."
  (with-current-buffer byte-compile--outbuffer
    (let ((position (point)))

      ;; Insert EXP, and make it a comment with #@LENGTH.
      (insert " ")
      (if quoted
          (prin1 exp byte-compile--outbuffer)
        (princ exp byte-compile--outbuffer))
      (goto-char position)
      ;; Quote certain special characters as needed.
      ;; get_doc_string in doc.c does the unquoting.
      (while (search-forward "\^A" nil t)
        (replace-match "\^A\^A" t t))
      (goto-char position)
      (while (search-forward "\000" nil t)
        (replace-match "\^A0" t t))
      (goto-char position)
      (while (search-forward "\037" nil t)
        (replace-match "\^A_" t t))
      (goto-char (point-max))
      (insert "\037")
      (goto-char position)
      (insert "#@" (format "%d" (- (position-bytes (point-max))
                                   (position-bytes position))))

      ;; Save the file position of the object.
      ;; Note we add 1 to skip the space that we inserted before the actual doc
      ;; string, and subtract point-min to convert from an 1-origin Emacs
      ;; position to a file position.
      (prog1
          (- (position-bytes (point)) (point-min) -1)
        (goto-char (point-max))))))

(defun byte-compile--reify-function (fun)
  "Return an expression which will evaluate to a function value FUN.
FUN should be either a `lambda' value or a `closure' value."
  (pcase-let* (((or (and `(lambda ,args . ,body) (let env nil))
                    `(closure ,env ,args . ,body))
                fun)
               (preamble nil)
               (renv ()))
    ;; Split docstring and `interactive' form from body.
    (when (stringp (car body))
      (push (pop body) preamble))
    (when (eq (car-safe (car body)) 'interactive)
      (push (pop body) preamble))
    ;; Turn the function's closed vars (if any) into local let bindings.
    (dolist (binding env)
      (cond
       ((consp binding)
        ;; We check shadowing by the args, so that the `let' can be moved
        ;; within the lambda, which can then be unfolded.  FIXME: Some of those
        ;; bindings might be unused in `body'.
        (unless (memq (car binding) args) ;Shadowed.
          (push `(,(car binding) ',(cdr binding)) renv)))
       ((eq binding t))
       (t (push `(defvar ,binding) body))))
    (if (null renv)
        `(lambda ,args ,@preamble ,@body)
      `(lambda ,args ,@preamble (let ,(nreverse renv) ,@body)))))
\f
;;;###autoload
(defun byte-compile (form)
  "If FORM is a symbol, byte-compile its function definition.
If FORM is a lambda or a macro, byte-compile it as a function."
  (displaying-byte-compile-warnings
   (byte-compile-close-variables
    (let* ((lexical-binding lexical-binding)
           (fun (if (symbolp form)
                    (symbol-function form)
                  form))
           (macro (eq (car-safe fun) 'macro)))
      (if macro
          (setq fun (cdr fun)))
      (cond
       ;; Up until Emacs-24.1, byte-compile silently did nothing when asked to
       ;; compile something invalid.  So let's tune down the complaint from an
       ;; error to a simple message for the known case where signaling an error
       ;; causes problems.
       ((byte-code-function-p fun)
        (message "Function %s is already compiled"
                 (if (symbolp form) form "provided"))
        fun)
       (t
        (when (or (symbolp form) (eq (car-safe fun) 'closure))
          ;; `fun' is a function *value*, so try to recover its corresponding
          ;; source code.
          (setq lexical-binding (eq (car fun) 'closure))
          (setq fun (byte-compile--reify-function fun)))
        ;; Expand macros.
        (setq fun (byte-compile-preprocess fun))
        (setq fun (byte-compile-top-level fun nil 'eval))
        (if macro (push 'macro fun))
        (if (symbolp form)
            (fset form fun)
          fun)))))))

(defun byte-compile-sexp (sexp)
  "Compile and return SEXP."
  (displaying-byte-compile-warnings
   (byte-compile-close-variables
    (byte-compile-top-level (byte-compile-preprocess sexp)))))

(defun byte-compile-check-lambda-list (list)
  "Check lambda-list LIST for errors."
  (let (vars)
    (while list
      (let ((arg (car list)))
        (when (symbolp arg)
          (byte-compile-set-symbol-position arg))
        (cond ((or (not (symbolp arg))
                   (macroexp--const-symbol-p arg t))
               (error "Invalid lambda variable %s" arg))
              ((eq arg '&rest)
               (unless (cdr list)
                 (error "&rest without variable name"))
               (when (cddr list)
                 (error "Garbage following &rest VAR in lambda-list")))
              ((eq arg '&optional)
               (when (or (null (cdr list))
                         (memq (cadr list) '(&optional &rest)))
                 (error "Variable name missing after &optional"))
               (when (memq '&optional (cddr list))
                 (error "Duplicate &optional")))
              ((memq arg vars)
               (byte-compile-warn "repeated variable %s in lambda-list" arg))
              (t
               (push arg vars))))
      (setq list (cdr list)))))


(defun byte-compile-arglist-vars (arglist)
  "Return a list of the variables in the lambda argument list ARGLIST."
  (remq '&rest (remq '&optional arglist)))

(defun byte-compile-make-lambda-lexenv (args)
  "Return a new lexical environment for a lambda expression FORM."
  (let* ((lexenv nil)
         (stackpos 0))
    ;; Add entries for each argument.
    (dolist (arg args)
      (push (cons arg stackpos) lexenv)
      (setq stackpos (1+ stackpos)))
    ;; Return the new lexical environment.
    lexenv))

(defun byte-compile-make-args-desc (arglist)
  (let ((mandatory 0)
        nonrest (rest 0))
    (while (and arglist (not (memq (car arglist) '(&optional &rest))))
      (setq mandatory (1+ mandatory))
      (setq arglist (cdr arglist)))
    (setq nonrest mandatory)
    (when (eq (car arglist) '&optional)
      (setq arglist (cdr arglist))
      (while (and arglist (not (eq (car arglist) '&rest)))
        (setq nonrest (1+ nonrest))
        (setq arglist (cdr arglist))))
    (when arglist
      (setq rest 1))
    (if (> mandatory 127)
        (byte-compile-report-error "Too many (>127) mandatory arguments")
      (logior mandatory
              (lsh nonrest 8)
              (lsh rest 7)))))


(defun byte-compile-lambda (fun &optional add-lambda reserved-csts)
  "Byte-compile a lambda-expression and return a valid function.
The value is usually a compiled function but may be the original
lambda-expression.
When ADD-LAMBDA is non-nil, the symbol `lambda' is added as head
of the list FUN and `byte-compile-set-symbol-position' is not called.
Use this feature to avoid calling `byte-compile-set-symbol-position'
for symbols generated by the byte compiler itself."
  (if add-lambda
      (setq fun (cons 'lambda fun))
    (unless (eq 'lambda (car-safe fun))
      (error "Not a lambda list: %S" fun))
    (byte-compile-set-symbol-position 'lambda))
  (byte-compile-check-lambda-list (nth 1 fun))
  (let* ((arglist (nth 1 fun))
         (arglistvars (byte-compile-arglist-vars arglist))
         (byte-compile-bound-variables
          (append (if (not lexical-binding) arglistvars)
                  byte-compile-bound-variables))
         (body (cdr (cdr fun)))
         (doc (if (stringp (car body))
                  (prog1 (car body)
                    ;; Discard the doc string
                    ;; unless it is the last element of the body.
                    (if (cdr body)
                        (setq body (cdr body))))))
         (int (assq 'interactive body)))
    ;; Process the interactive spec.
    (when int
      (byte-compile-set-symbol-position 'interactive)
      ;; Skip (interactive) if it is in front (the most usual location).
      (if (eq int (car body))
          (setq body (cdr body)))
      (cond ((consp (cdr int))
             (if (cdr (cdr int))
                 (byte-compile-warn "malformed interactive spec: %s"
                                    (prin1-to-string int)))
             ;; If the interactive spec is a call to `list', don't
             ;; compile it, because `call-interactively' looks at the
             ;; args of `list'.  Actually, compile it to get warnings,
             ;; but don't use the result.
             (let* ((form (nth 1 int))
                    (newform (byte-compile-top-level form)))
               (while (memq (car-safe form) '(let let* progn save-excursion))
                 (while (consp (cdr form))
                   (setq form (cdr form)))
                 (setq form (car form)))
               (if (and (eq (car-safe form) 'list)
                        ;; The spec is evalled in callint.c in dynamic-scoping
                        ;; mode, so just leaving the form unchanged would mean
                        ;; it won't be eval'd in the right mode.
                        (not lexical-binding))
                   nil
                 (setq int `(interactive ,newform)))))
            ((cdr int)
             (byte-compile-warn "malformed interactive spec: %s"
                                (prin1-to-string int)))))
    ;; Process the body.
    (let ((compiled
           (byte-compile-top-level (cons 'progn body) nil 'lambda
                                   ;; If doing lexical binding, push a new
                                   ;; lexical environment containing just the
                                   ;; args (since lambda expressions should be
                                   ;; closed by now).
                                   (and lexical-binding
                                        (byte-compile-make-lambda-lexenv
                                         arglistvars))
                                   reserved-csts)))
      ;; Build the actual byte-coded function.
      (cl-assert (eq 'byte-code (car-safe compiled)))
      (apply #'make-byte-code
             (if lexical-binding
                 (byte-compile-make-args-desc arglist)
               arglist)
             (append
              ;; byte-string, constants-vector, stack depth
              (cdr compiled)
              ;; optionally, the doc string.
              (cond ((and lexical-binding arglist)
                     ;; byte-compile-make-args-desc lost the args's names,
                     ;; so preserve them in the docstring.
                     (list (help-add-fundoc-usage doc arglist)))
                    ((or doc int)
                     (list doc)))
              ;; optionally, the interactive spec.
              (if int
                  (list (nth 1 int))))))))

(defvar byte-compile-reserved-constants 0)

(defun byte-compile-constants-vector ()
  ;; Builds the constants-vector from the current variables and constants.
  ;;   This modifies the constants from (const . nil) to (const . offset).
  ;; To keep the byte-codes to look up the vector as short as possible:
  ;;   First 6 elements are vars, as there are one-byte varref codes for those.
  ;;   Next up to byte-constant-limit are constants, still with one-byte codes.
  ;;   Next variables again, to get 2-byte codes for variable lookup.
  ;;   The rest of the constants and variables need 3-byte byte-codes.
  (let* ((i (1- byte-compile-reserved-constants))
         (rest (nreverse byte-compile-variables)) ; nreverse because the first
         (other (nreverse byte-compile-constants)) ; vars often are used most.
         ret tmp
         (limits '(5                    ; Use the 1-byte varref codes,
                   63  ; 1-constlim     ;  1-byte byte-constant codes,
                   255                  ;  2-byte varref codes,
                   65535                ;  3-byte codes for the rest.
                   65535))              ;  twice since we step when we swap.
         limit)
    (while (or rest other)
      (setq limit (car limits))
      (while (and rest (< i limit))
        (cond
         ((numberp (car rest))
          (cl-assert (< (car rest) byte-compile-reserved-constants)))
         ((setq tmp (assq (car (car rest)) ret))
          (setcdr (car rest) (cdr tmp)))
         (t
          (setcdr (car rest) (setq i (1+ i)))
          (setq ret (cons (car rest) ret))))
        (setq rest (cdr rest)))
      (setq limits (cdr limits)         ;Step
            rest (prog1 other           ;&Swap.
                   (setq other rest))))
    (apply 'vector (nreverse (mapcar 'car ret)))))

;; Given an expression FORM, compile it and return an equivalent byte-code
;; expression (a call to the function byte-code).
(defun byte-compile-top-level (form &optional for-effect output-type
                                    lexenv reserved-csts)
  ;; OUTPUT-TYPE advises about how form is expected to be used:
  ;;    'eval or nil    -> a single form,
  ;;    'progn or t     -> a list of forms,
  ;;    'lambda         -> body of a lambda,
  ;;    'file           -> used at file-level.
  (let ((byte-compile--for-effect for-effect)
        (byte-compile-constants nil)
        (byte-compile-variables nil)
        (byte-compile-tag-number 0)
        (byte-compile-depth 0)
        (byte-compile-maxdepth 0)
        (byte-compile--lexical-environment lexenv)
        (byte-compile-reserved-constants (or reserved-csts 0))
        (byte-compile-output nil)
        (byte-compile-jump-tables nil))
    (if (memq byte-optimize '(t source))
        (setq form (byte-optimize-form form byte-compile--for-effect)))
    (while (and (eq (car-safe form) 'progn) (null (cdr (cdr form))))
      (setq form (nth 1 form)))
    ;; Set up things for a lexically-bound function.
    (when (and lexical-binding (eq output-type 'lambda))
      ;; See how many arguments there are, and set the current stack depth
      ;; accordingly.
      (setq byte-compile-depth (length byte-compile--lexical-environment))
      ;; If there are args, output a tag to record the initial
      ;; stack-depth for the optimizer.
      (when (> byte-compile-depth 0)
        (byte-compile-out-tag (byte-compile-make-tag))))
    ;; Now compile FORM
    (byte-compile-form form byte-compile--for-effect)
    (byte-compile-out-toplevel byte-compile--for-effect output-type)))

(defun byte-compile-out-toplevel (&optional for-effect output-type)
  (if for-effect
      ;; The stack is empty. Push a value to be returned from (byte-code ..).
      (if (eq (car (car byte-compile-output)) 'byte-discard)
          (setq byte-compile-output (cdr byte-compile-output))
        (byte-compile-push-constant
         ;; Push any constant - preferably one which already is used, and
         ;; a number or symbol - ie not some big sequence.  The return value
         ;; isn't returned, but it would be a shame if some textually large
         ;; constant was not optimized away because we chose to return it.
         (and (not (assq nil byte-compile-constants)) ; Nil is often there.
              (let ((tmp (reverse byte-compile-constants)))
                (while (and tmp (not (or (symbolp (caar tmp))
                                         (numberp (caar tmp)))))
                  (setq tmp (cdr tmp)))
                (caar tmp))))))
  (byte-compile-out 'byte-return 0)
  (setq byte-compile-output (nreverse byte-compile-output))
  (if (memq byte-optimize '(t byte))
      (setq byte-compile-output
            (byte-optimize-lapcode byte-compile-output)))

  ;; Decompile trivial functions:
  ;; only constants and variables, or a single funcall except in lambdas.
  ;; Except for Lisp_Compiled objects, forms like (foo "hi")
  ;; are still quicker than (byte-code "..." [foo "hi"] 2).
  ;; Note that even (quote foo) must be parsed just as any subr by the
  ;; interpreter, so quote should be compiled into byte-code in some contexts.
  ;; What to leave uncompiled:
  ;;    lambda  -> never.  we used to leave it uncompiled if the body was
  ;;               a single atom, but that causes confusion if the docstring
  ;;               uses the (file . pos) syntax.  Besides, now that we have
  ;;               the Lisp_Compiled type, the compiled form is faster.
  ;;    eval    -> atom, quote or (function atom atom atom)
  ;;    progn   -> as <<same-as-eval>> or (progn <<same-as-eval>> atom)
  ;;    file    -> as progn, but takes both quotes and atoms, and longer forms.
  (let (rest
        (maycall (not (eq output-type 'lambda))) ; t if we may make a funcall.
        tmp body)
    (cond
     ;; #### This should be split out into byte-compile-nontrivial-function-p.
     ((or (eq output-type 'lambda)
          (nthcdr (if (eq output-type 'file) 50 8) byte-compile-output)
          (assq 'TAG byte-compile-output) ; Not necessary, but speeds up a bit.
          (not (setq tmp (assq 'byte-return byte-compile-output)))
          (progn
            (setq rest (nreverse
                        (cdr (memq tmp (reverse byte-compile-output)))))
            (while
                (cond
                 ((memq (car (car rest)) '(byte-varref byte-constant))
                  (setq tmp (car (cdr (car rest))))
                  (if (if (eq (car (car rest)) 'byte-constant)
                          (or (consp tmp)
                              (and (symbolp tmp)
                                   (not (macroexp--const-symbol-p tmp)))))
                      (if maycall
                          (setq body (cons (list 'quote tmp) body)))
                    (setq body (cons tmp body))))
                 ((and maycall
                       ;; Allow a funcall if at most one atom follows it.
                       (null (nthcdr 3 rest))
                       (setq tmp (get (car (car rest)) 'byte-opcode-invert))
                       (or (null (cdr rest))
                           (and (memq output-type '(file progn t))
                                (cdr (cdr rest))
                                (eq (car (nth 1 rest)) 'byte-discard)
                                (progn (setq rest (cdr rest)) t))))
                  (setq maycall nil)    ; Only allow one real function call.
                  (setq body (nreverse body))
                  (setq body (list
                              (if (and (eq tmp 'funcall)
                                       (eq (car-safe (car body)) 'quote)
                                       (symbolp (nth 1 (car body))))
                                  (cons (nth 1 (car body)) (cdr body))
                                (cons tmp body))))
                  (or (eq output-type 'file)
                      (not (delq nil (mapcar 'consp (cdr (car body))))))))
              (setq rest (cdr rest)))
            rest))
      (let ((byte-compile-vector (byte-compile-constants-vector)))
        (list 'byte-code (byte-compile-lapcode byte-compile-output)
              byte-compile-vector byte-compile-maxdepth)))
     ;; it's a trivial function
     ((cdr body) (cons 'progn (nreverse body)))
     ((car body)))))

;; Given BODY, compile it and return a new body.
(defun byte-compile-top-level-body (body &optional for-effect)
  (setq body
        (byte-compile-top-level (cons 'progn body) for-effect t))
  (cond ((eq (car-safe body) 'progn)
         (cdr body))
        (body
         (list body))))

;; Special macro-expander used during byte-compilation.
(defun byte-compile-macroexpand-declare-function (fn file &rest args)
  (declare (advertised-calling-convention
            (fn file &optional arglist fileonly) nil))
  (let ((gotargs (and (consp args) (listp (car args))))
        (unresolved (assq fn byte-compile-unresolved-functions)))
    (when unresolved          ; function was called before declaration
      (if (and gotargs (byte-compile-warning-enabled-p 'callargs))
          (byte-compile-arglist-warn fn (car args) nil)
        (setq byte-compile-unresolved-functions
              (delq unresolved byte-compile-unresolved-functions))))
    (push (cons fn (if gotargs
                       (list 'declared (car args))
                     t))                     ; Arglist not specified.
          byte-compile-function-environment))
  ;; We are stating that it _will_ be defined at runtime.
  (setq byte-compile-noruntime-functions
        (delq fn byte-compile-noruntime-functions))
  ;; Delegate the rest to the normal macro definition.
  (macroexpand `(declare-function ,fn ,file ,@args)))

\f
;; This is the recursive entry point for compiling each subform of an
;; expression.
;; If for-effect is non-nil, byte-compile-form will output a byte-discard
;; before terminating (ie no value will be left on the stack).
;; A byte-compile handler may, when byte-compile--for-effect is non-nil, choose
;; output code which does not leave a value on the stack, and then set
;; byte-compile--for-effect to nil (to prevent byte-compile-form from
;; outputting the byte-discard).
;; If a handler wants to call another handler, it should do so via
;; byte-compile-form, or take extreme care to handle byte-compile--for-effect
;; correctly.  (Use byte-compile-form-do-effect to reset the
;; byte-compile--for-effect flag too.)
;;
(defun byte-compile-form (form &optional for-effect)
  (let ((byte-compile--for-effect for-effect))
    (cond
     ((not (consp form))
      (cond ((or (not (symbolp form)) (macroexp--const-symbol-p form))
             (when (symbolp form)
               (byte-compile-set-symbol-position form))
             (byte-compile-constant form))
            ((and byte-compile--for-effect byte-compile-delete-errors)
             (when (symbolp form)
               (byte-compile-set-symbol-position form))
             (setq byte-compile--for-effect nil))
            (t
             (byte-compile-variable-ref form))))
     ((symbolp (car form))
      (let* ((fn (car form))
             (handler (get fn 'byte-compile))
             (interactive-only
              (or (get fn 'interactive-only)
                  (memq fn byte-compile-interactive-only-functions))))
        (when (memq fn '(set symbol-value run-hooks ;; add-to-list
                             add-hook remove-hook run-hook-with-args
                             run-hook-with-args-until-success
                             run-hook-with-args-until-failure))
          (pcase (cdr form)
            (`(',var . ,_)
             (when (assq var byte-compile-lexical-variables)
               (byte-compile-report-error
                (format-message "%s cannot use lexical var `%s'" fn var))))))
        (when (macroexp--const-symbol-p fn)
          (byte-compile-warn "`%s' called as a function" fn))
        (when (and (byte-compile-warning-enabled-p 'interactive-only)
                   interactive-only)
          (byte-compile-warn "`%s' is for interactive use only%s"
                             fn
                             (cond ((stringp interactive-only)
                                    (format "; %s"
                                            (substitute-command-keys
                                             interactive-only)))
                                   ((and (symbolp 'interactive-only)
                                         (not (eq interactive-only t)))
                                    (format-message "; use `%s' instead."
                                                    interactive-only))
                                   (t "."))))
        (if (eq (car-safe (symbol-function (car form))) 'macro)
            (byte-compile-report-error
             (format "Forgot to expand macro %s in %S" (car form) form)))
        (if (and handler
                 ;; Make sure that function exists.
                 (and (functionp handler)
                      ;; Ignore obsolete byte-compile function used by former
                      ;; CL code to handle compiler macros (we do it
                      ;; differently now).
                      (not (eq handler 'cl-byte-compile-compiler-macro))))
            (funcall handler form)
          (byte-compile-normal-call form))
        (if (byte-compile-warning-enabled-p 'cl-functions)
            (byte-compile-cl-warn form))))
     ((and (byte-code-function-p (car form))
           (memq byte-optimize '(t lap)))
      (byte-compile-unfold-bcf form))
     ((and (eq (car-safe (car form)) 'lambda)
           ;; if the form comes out the same way it went in, that's
           ;; because it was malformed, and we couldn't unfold it.
           (not (eq form (setq form (byte-compile-unfold-lambda form)))))
      (byte-compile-form form byte-compile--for-effect)
      (setq byte-compile--for-effect nil))
     ((byte-compile-normal-call form)))
    (if byte-compile--for-effect
        (byte-compile-discard))))

(defun byte-compile-normal-call (form)
  (when (and (byte-compile-warning-enabled-p 'callargs)
             (symbolp (car form)))
    (if (memq (car form)
              '(custom-declare-group custom-declare-variable
                                     custom-declare-face))
        (byte-compile-nogroup-warn form))
    (byte-compile-callargs-warn form))
  (if byte-compile-generate-call-tree
      (byte-compile-annotate-call-tree form))
  (when (and byte-compile--for-effect (eq (car form) 'mapcar)
             (byte-compile-warning-enabled-p 'mapcar))
    (byte-compile-set-symbol-position 'mapcar)
    (byte-compile-warn
     "`mapcar' called for effect; use `mapc' or `dolist' instead"))
  (byte-compile-push-constant (car form))
  (mapc 'byte-compile-form (cdr form))  ; wasteful, but faster.
  (byte-compile-out 'byte-call (length (cdr form))))


;; Splice the given lap code into the current instruction stream.
;; If it has any labels in it, you're responsible for making sure there
;; are no collisions, and that byte-compile-tag-number is reasonable
;; after this is spliced in.  The provided list is destroyed.
(defun byte-compile-inline-lapcode (lap end-depth)
  ;; "Replay" the operations: we used to just do
  ;; (setq byte-compile-output (nconc (nreverse lap) byte-compile-output))
  ;; but that fails to update byte-compile-depth, so we had to assume
  ;; that `lap' ends up adding exactly 1 element to the stack.  This
  ;; happens to be true for byte-code generated by bytecomp.el without
  ;; lexical-binding, but it's not true in general, and it's not true for
  ;; code output by bytecomp.el with lexical-binding.
  ;; We also restore the value of `byte-compile-depth' and remove TAG depths
  ;; accordingly when inlining lapcode containing lap-code, exactly as
  ;; documented in `byte-compile-cond-jump-table'.
  (let ((endtag (byte-compile-make-tag))
        last-jump-tag ;; last TAG we have jumped to
        last-depth ;; last value of `byte-compile-depth'
        last-constant ;; value of the last constant encountered
        last-switch ;; whether the last op encountered was byte-switch
        switch-tags ;; a list of tags that byte-switch could jump to
        ;; a list of tags byte-switch will jump to, if the value doesn't
        ;; match any entry in the hash table
        switch-default-tags)
    (dolist (op lap)
      (cond
       ((eq (car op) 'TAG)
        (when (or (member op switch-tags) (member op switch-default-tags))
          ;; This TAG is used in a jump table, this means the last goto
          ;; was to a done/default TAG, and thus it's cddr should be set to nil.
          (when last-jump-tag
            (setcdr (cdr last-jump-tag) nil))
          ;; Also, restore the value of `byte-compile-depth' to what it was
          ;; before the last goto.
          (setq byte-compile-depth last-depth
                last-jump-tag nil))
        (byte-compile-out-tag op))
       ((memq (car op) byte-goto-ops)
        (setq last-depth byte-compile-depth
              last-jump-tag (cdr op))
        (byte-compile-goto (car op) (cdr op))
        (when last-switch
          ;; The last op was byte-switch, this goto jumps to a "default" TAG
          ;; (when no value in the jump table is satisfied).
          (push (cdr op) switch-default-tags)
          (setcdr (cdr (cdr op)) nil)
          (setq byte-compile-depth last-depth
                last-switch nil)))
       ((eq (car op) 'byte-return)
        (byte-compile-discard (- byte-compile-depth end-depth) t)
        (byte-compile-goto 'byte-goto endtag))
       (t
        (when (eq (car op) 'byte-switch)
          ;; The last constant is a jump table.
          (push last-constant byte-compile-jump-tables)
          (setq last-switch t)
          ;; Push all TAGs in the jump to switch-tags.
          (maphash #'(lambda (_k tag)
                       (push tag switch-tags))
                   last-constant))
        (setq last-constant (and (eq (car op) 'byte-constant) (cadr op)))
        (setq last-depth byte-compile-depth)
        (byte-compile-out (car op) (cdr op)))))
    (byte-compile-out-tag endtag)))

(defun byte-compile-unfold-bcf (form)
  "Inline call to byte-code-functions."
  (let* ((byte-compile-bound-variables byte-compile-bound-variables)
         (fun (car form))
         (fargs (aref fun 0))
         (start-depth byte-compile-depth)
         (fmax2 (if (numberp fargs) (lsh fargs -7)))     ;2*max+rest.
         ;; (fmin (if (numberp fargs) (logand fargs 127)))
         (alen (length (cdr form)))
         (dynbinds ()))
    (fetch-bytecode fun)
    (mapc 'byte-compile-form (cdr form))
    (unless fmax2
      ;; Old-style byte-code.
      (cl-assert (listp fargs))
      (while fargs
        (pcase (car fargs)
          (`&optional (setq fargs (cdr fargs)))
          (`&rest (setq fmax2 (+ (* 2 (length dynbinds)) 1))
                 (push (cadr fargs) dynbinds)
                 (setq fargs nil))
          (_ (push (pop fargs) dynbinds))))
      (unless fmax2 (setq fmax2 (* 2 (length dynbinds)))))
    (cond
     ((<= (+ alen alen) fmax2)
      ;; Add missing &optional (or &rest) arguments.
      (dotimes (_ (- (/ (1+ fmax2) 2) alen))
        (byte-compile-push-constant nil)))
     ((zerop (logand fmax2 1))
      (byte-compile-report-error
       (format "Too many arguments for inlined function %S" form))
      (byte-compile-discard (- alen (/ fmax2 2))))
     (t
      ;; Turn &rest args into a list.
      (let ((n (- alen (/ (1- fmax2) 2))))
        (cl-assert (> n 0) nil "problem: fmax2=%S alen=%S n=%S" fmax2 alen n)
        (if (< n 5)
            (byte-compile-out
             (aref [byte-list1 byte-list2 byte-list3 byte-list4] (1- n))
             0)
          (byte-compile-out 'byte-listN n)))))
    (mapc #'byte-compile-dynamic-variable-bind dynbinds)
    (byte-compile-inline-lapcode
     (byte-decompile-bytecode-1 (aref fun 1) (aref fun 2) t)
     (1+ start-depth))
    ;; Unbind dynamic variables.
    (when dynbinds
      (byte-compile-out 'byte-unbind (length dynbinds)))
    (cl-assert (eq byte-compile-depth (1+ start-depth))
            nil "Wrong depth start=%s end=%s" start-depth byte-compile-depth)))

(defun byte-compile-check-variable (var access-type)
  "Do various error checks before a use of the variable VAR."
  (when (symbolp var)
    (byte-compile-set-symbol-position var))
  (cond ((or (not (symbolp var)) (macroexp--const-symbol-p var))
         (when (byte-compile-warning-enabled-p 'constants)
           (byte-compile-warn (if (eq access-type 'let-bind)
                                  "attempt to let-bind %s `%s'"
                                "variable reference to %s `%s'")
                              (if (symbolp var) "constant" "nonvariable")
                              (prin1-to-string var))))
        ((let ((od (get var 'byte-obsolete-variable)))
           (and od
                (not (memq var byte-compile-not-obsolete-vars))
                (not (memq var byte-compile-global-not-obsolete-vars))
                (or (pcase (nth 1 od)
                      (`set (not (eq access-type 'reference)))
                      (`get (eq access-type 'reference))
                      (_ t)))))
         (byte-compile-warn-obsolete var))))

(defsubst byte-compile-dynamic-variable-op (base-op var)
  (let ((tmp (assq var byte-compile-variables)))
    (unless tmp
      (setq tmp (list var))
      (push tmp byte-compile-variables))
    (byte-compile-out base-op tmp)))

(defun byte-compile-dynamic-variable-bind (var)
  "Generate code to bind the lexical variable VAR to the top-of-stack value."
  (byte-compile-check-variable var 'let-bind)
  (push var byte-compile-bound-variables)
  (byte-compile-dynamic-variable-op 'byte-varbind var))

(defun byte-compile-variable-ref (var)
  "Generate code to push the value of the variable VAR on the stack."
  (byte-compile-check-variable var 'reference)
  (let ((lex-binding (assq var byte-compile--lexical-environment)))
    (if lex-binding
        ;; VAR is lexically bound
        (byte-compile-stack-ref (cdr lex-binding))
      ;; VAR is dynamically bound
      (unless (or (not (byte-compile-warning-enabled-p 'free-vars))
                  (boundp var)
                  (memq var byte-compile-bound-variables)
                  (memq var byte-compile-free-references))
        (byte-compile-warn "reference to free variable `%S'" var)
        (push var byte-compile-free-references))
      (byte-compile-dynamic-variable-op 'byte-varref var))))

(defun byte-compile-variable-set (var)
  "Generate code to set the variable VAR from the top-of-stack value."
  (byte-compile-check-variable var 'assign)
  (let ((lex-binding (assq var byte-compile--lexical-environment)))
    (if lex-binding
        ;; VAR is lexically bound.
        (byte-compile-stack-set (cdr lex-binding))
      ;; VAR is dynamically bound.
      (unless (or (not (byte-compile-warning-enabled-p 'free-vars))
                  (boundp var)
                  (memq var byte-compile-bound-variables)
                  (memq var byte-compile-free-assignments))
        (byte-compile-warn "assignment to free variable `%s'" var)
        (push var byte-compile-free-assignments))
      (byte-compile-dynamic-variable-op 'byte-varset var))))

(defmacro byte-compile-get-constant (const)
  `(or (if (stringp ,const)
           ;; In a string constant, treat properties as significant.
           (let (result)
             (dolist (elt byte-compile-constants)
               (if (equal-including-properties (car elt) ,const)
                   (setq result elt)))
             result)
         (assq ,const byte-compile-constants))
       (car (setq byte-compile-constants
                  (cons (list ,const) byte-compile-constants)))))

;; Use this when the value of a form is a constant.
;; This obeys byte-compile--for-effect.
(defun byte-compile-constant (const)
  (if byte-compile--for-effect
      (setq byte-compile--for-effect nil)
    (when (symbolp const)
      (byte-compile-set-symbol-position const))
    (byte-compile-out 'byte-constant (byte-compile-get-constant const))))

;; Use this for a constant that is not the value of its containing form.
;; This ignores byte-compile--for-effect.
(defun byte-compile-push-constant (const)
  (let ((byte-compile--for-effect nil))
    (inline (byte-compile-constant const))))
\f
;; Compile those primitive ordinary functions
;; which have special byte codes just for speed.

(defmacro byte-defop-compiler (function &optional compile-handler)
  "Add a compiler-form for FUNCTION.
If function is a symbol, then the variable \"byte-SYMBOL\" must name
the opcode to be used.  If function is a list, the first element
is the function and the second element is the bytecode-symbol.
The second element may be nil, meaning there is no opcode.
COMPILE-HANDLER is the function to use to compile this byte-op, or
may be the abbreviations 0, 1, 2, 3, 0-1, or 1-2.
If it is nil, then the handler is \"byte-compile-SYMBOL.\""
  (let (opcode)
    (if (symbolp function)
        (setq opcode (intern (concat "byte-" (symbol-name function))))
      (setq opcode (car (cdr function))
            function (car function)))
    (let ((fnform
           (list 'put (list 'quote function) ''byte-compile
                 (list 'quote
                       (or (cdr (assq compile-handler
                                      '((0 . byte-compile-no-args)
                                        (1 . byte-compile-one-arg)
                                        (2 . byte-compile-two-args)
                                        (2-and . byte-compile-and-folded)
                                        (3 . byte-compile-three-args)
                                        (0-1 . byte-compile-zero-or-one-arg)
                                        (1-2 . byte-compile-one-or-two-args)
                                        (2-3 . byte-compile-two-or-three-args)
                                        )))
                           compile-handler
                           (intern (concat "byte-compile-"
                                           (symbol-name function))))))))
      (if opcode
          (list 'progn fnform
                (list 'put (list 'quote function)
                      ''byte-opcode (list 'quote opcode))
                (list 'put (list 'quote opcode)
                      ''byte-opcode-invert (list 'quote function)))
        fnform))))

(defmacro byte-defop-compiler-1 (function &optional compile-handler)
  (list 'byte-defop-compiler (list function nil) compile-handler))

\f
(put 'byte-call 'byte-opcode-invert 'funcall)
(put 'byte-list1 'byte-opcode-invert 'list)
(put 'byte-list2 'byte-opcode-invert 'list)
(put 'byte-list3 'byte-opcode-invert 'list)
(put 'byte-list4 'byte-opcode-invert 'list)
(put 'byte-listN 'byte-opcode-invert 'list)
(put 'byte-concat2 'byte-opcode-invert 'concat)
(put 'byte-concat3 'byte-opcode-invert 'concat)
(put 'byte-concat4 'byte-opcode-invert 'concat)
(put 'byte-concatN 'byte-opcode-invert 'concat)
(put 'byte-insertN 'byte-opcode-invert 'insert)

(byte-defop-compiler point              0)
;;(byte-defop-compiler mark             0) ;; obsolete
(byte-defop-compiler point-max          0)
(byte-defop-compiler point-min          0)
(byte-defop-compiler following-char     0)
(byte-defop-compiler preceding-char     0)
(byte-defop-compiler current-column     0)
(byte-defop-compiler eolp               0)
(byte-defop-compiler eobp               0)
(byte-defop-compiler bolp               0)
(byte-defop-compiler bobp               0)
(byte-defop-compiler current-buffer     0)
;;(byte-defop-compiler read-char        0) ;; obsolete
;; (byte-defop-compiler interactive-p   0) ;; Obsolete.
(byte-defop-compiler widen              0)
(byte-defop-compiler end-of-line    0-1)
(byte-defop-compiler forward-char   0-1)
(byte-defop-compiler forward-line   0-1)
(byte-defop-compiler symbolp            1)
(byte-defop-compiler consp              1)
(byte-defop-compiler stringp            1)
(byte-defop-compiler listp              1)
(byte-defop-compiler not                1)
(byte-defop-compiler (null byte-not)    1)
(byte-defop-compiler car                1)
(byte-defop-compiler cdr                1)
(byte-defop-compiler length             1)
(byte-defop-compiler symbol-value       1)
(byte-defop-compiler symbol-function    1)
(byte-defop-compiler (1+ byte-add1)     1)
(byte-defop-compiler (1- byte-sub1)     1)
(byte-defop-compiler goto-char          1)
(byte-defop-compiler char-after         0-1)
(byte-defop-compiler set-buffer         1)
;;(byte-defop-compiler set-mark         1) ;; obsolete
(byte-defop-compiler forward-word       0-1)
(byte-defop-compiler char-syntax        1)
(byte-defop-compiler nreverse           1)
(byte-defop-compiler car-safe           1)
(byte-defop-compiler cdr-safe           1)
(byte-defop-compiler numberp            1)
(byte-defop-compiler integerp           1)
(byte-defop-compiler skip-chars-forward     1-2)
(byte-defop-compiler skip-chars-backward    1-2)
(byte-defop-compiler eq                 2)
(byte-defop-compiler memq               2)
(byte-defop-compiler cons               2)
(byte-defop-compiler aref               2)
(byte-defop-compiler set                2)
(byte-defop-compiler (= byte-eqlsign)   2-and)
(byte-defop-compiler (< byte-lss)       2-and)
(byte-defop-compiler (> byte-gtr)       2-and)
(byte-defop-compiler (<= byte-leq)      2-and)
(byte-defop-compiler (>= byte-geq)      2-and)
(byte-defop-compiler get                2)
(byte-defop-compiler nth                2)
(byte-defop-compiler substring          2-3)
(byte-defop-compiler (move-marker byte-set-marker) 2-3)
(byte-defop-compiler set-marker 2-3)
(byte-defop-compiler match-beginning    1)
(byte-defop-compiler match-end  1)
(byte-defop-compiler upcase             1)
(byte-defop-compiler downcase           1)
(byte-defop-compiler string=            2)
(byte-defop-compiler string<            2)
(byte-defop-compiler (string-equal byte-string=) 2)
(byte-defop-compiler (string-lessp byte-string<) 2)
(byte-defop-compiler equal              2)
(byte-defop-compiler nthcdr             2)
(byte-defop-compiler elt                2)
(byte-defop-compiler member             2)
(byte-defop-compiler assq               2)
(byte-defop-compiler (rplaca byte-setcar) 2)
(byte-defop-compiler (rplacd byte-setcdr) 2)
(byte-defop-compiler setcar             2)
(byte-defop-compiler setcdr             2)
(byte-defop-compiler buffer-substring   2)
(byte-defop-compiler delete-region      2)
(byte-defop-compiler narrow-to-region   2)
(byte-defop-compiler (% byte-rem)       2)
(byte-defop-compiler aset               3)

(byte-defop-compiler max                byte-compile-associative)
(byte-defop-compiler min                byte-compile-associative)
(byte-defop-compiler (+ byte-plus)      byte-compile-associative)
(byte-defop-compiler (* byte-mult)      byte-compile-associative)

;;####(byte-defop-compiler move-to-column       1)
(byte-defop-compiler-1 interactive byte-compile-noop)

\f
(defun byte-compile-subr-wrong-args (form n)
  (byte-compile-set-symbol-position (car form))
  (byte-compile-warn "`%s' called with %d arg%s, but requires %s"
                     (car form) (length (cdr form))
                     (if (= 1 (length (cdr form))) "" "s") n)
  ;; Get run-time wrong-number-of-args error.
  (byte-compile-normal-call form))

(defun byte-compile-no-args (form)
  (if (not (= (length form) 1))
      (byte-compile-subr-wrong-args form "none")
    (byte-compile-out (get (car form) 'byte-opcode) 0)))

(defun byte-compile-one-arg (form)
  (if (not (= (length form) 2))
      (byte-compile-subr-wrong-args form 1)
    (byte-compile-form (car (cdr form)))  ;; Push the argument
    (byte-compile-out (get (car form) 'byte-opcode) 0)))

(defun byte-compile-two-args (form)
  (if (not (= (length form) 3))
      (byte-compile-subr-wrong-args form 2)
    (byte-compile-form (car (cdr form)))  ;; Push the arguments
    (byte-compile-form (nth 2 form))
    (byte-compile-out (get (car form) 'byte-opcode) 0)))

(defun byte-compile-and-folded (form)
  "Compile calls to functions like `<='.
These implicitly `and' together a bunch of two-arg bytecodes."
  (let ((l (length form)))
    (cond
     ((< l 3) (byte-compile-form `(progn ,(nth 1 form) t)))
     ((= l 3) (byte-compile-two-args form))
     ((cl-every #'macroexp-copyable-p (nthcdr 2 form))
      (byte-compile-form `(and (,(car form) ,(nth 1 form) ,(nth 2 form))
                               (,(car form) ,@(nthcdr 2 form)))))
     (t (byte-compile-normal-call form)))))

(defun byte-compile-three-args (form)
  (if (not (= (length form) 4))
      (byte-compile-subr-wrong-args form 3)
    (byte-compile-form (car (cdr form)))  ;; Push the arguments
    (byte-compile-form (nth 2 form))
    (byte-compile-form (nth 3 form))
    (byte-compile-out (get (car form) 'byte-opcode) 0)))

(defun byte-compile-zero-or-one-arg (form)
  (let ((len (length form)))
    (cond ((= len 1) (byte-compile-one-arg (append form '(nil))))
          ((= len 2) (byte-compile-one-arg form))
          (t (byte-compile-subr-wrong-args form "0-1")))))

(defun byte-compile-one-or-two-args (form)
  (let ((len (length form)))
    (cond ((= len 2) (byte-compile-two-args (append form '(nil))))
          ((= len 3) (byte-compile-two-args form))
          (t (byte-compile-subr-wrong-args form "1-2")))))

(defun byte-compile-two-or-three-args (form)
  (let ((len (length form)))
    (cond ((= len 3) (byte-compile-three-args (append form '(nil))))
          ((= len 4) (byte-compile-three-args form))
          (t (byte-compile-subr-wrong-args form "2-3")))))

(defun byte-compile-noop (_form)
  (byte-compile-constant nil))

(defun byte-compile-discard (&optional num preserve-tos)
  "Output byte codes to discard the NUM entries at the top of the stack.
NUM defaults to 1.
If PRESERVE-TOS is non-nil, preserve the top-of-stack value, as if it were
popped before discarding the num values, and then pushed back again after
discarding."
  (if (and (null num) (not preserve-tos))
      ;; common case
      (byte-compile-out 'byte-discard)
    ;; general case
    (unless num
      (setq num 1))
    (when (and preserve-tos (> num 0))
      ;; Preserve the top-of-stack value by writing it directly to the stack
      ;; location which will be at the top-of-stack after popping.
      (byte-compile-stack-set (1- (- byte-compile-depth num)))
      ;; Now we actually discard one less value, since we want to keep
      ;; the eventual TOS
      (setq num (1- num)))
    (while (> num 0)
      (byte-compile-out 'byte-discard)
      (setq num (1- num)))))

(defun byte-compile-stack-ref (stack-pos)
  "Output byte codes to push the value at stack position STACK-POS."
  (let ((dist (- byte-compile-depth (1+ stack-pos))))
    (if (zerop dist)
        ;; A simple optimization
        (byte-compile-out 'byte-dup)
      ;; normal case
      (byte-compile-out 'byte-stack-ref dist))))

(defun byte-compile-stack-set (stack-pos)
  "Output byte codes to store the TOS value at stack position STACK-POS."
  (byte-compile-out 'byte-stack-set (- byte-compile-depth (1+ stack-pos))))

(byte-defop-compiler-1 internal-make-closure byte-compile-make-closure)
(byte-defop-compiler-1 internal-get-closed-var byte-compile-get-closed-var)

(defun byte-compile-make-closure (form)
  "Byte-compile the special `internal-make-closure' form."
  (if byte-compile--for-effect (setq byte-compile--for-effect nil)
    (let* ((vars (nth 1 form))
           (env (nth 2 form))
           (docstring-exp (nth 3 form))
           (body (nthcdr 4 form))
           (fun
            (byte-compile-lambda `(lambda ,vars . ,body) nil (length env))))
      (cl-assert (or (> (length env) 0)
                     docstring-exp))    ;Otherwise, we don't need a closure.
      (cl-assert (byte-code-function-p fun))
      (byte-compile-form `(make-byte-code
                           ',(aref fun 0) ',(aref fun 1)
                           (vconcat (vector . ,env) ',(aref fun 2))
                           ,@(let ((rest (nthcdr 3 (mapcar (lambda (x) `',x) fun))))
                               (if docstring-exp
                                   `(,(car rest)
                                     ,docstring-exp
                                     ,@(cddr rest))
                                 rest)))))))

(defun byte-compile-get-closed-var (form)
  "Byte-compile the special `internal-get-closed-var' form."
  (if byte-compile--for-effect (setq byte-compile--for-effect nil)
    (byte-compile-out 'byte-constant (nth 1 form))))

;; Compile a function that accepts one or more args and is right-associative.
;; We do it by left-associativity so that the operations
;; are done in the same order as in interpreted code.
;; We treat the one-arg case, as in (+ x), like (+ x 0).
;; in order to convert markers to numbers, and trigger expected errors.
(defun byte-compile-associative (form)
  (if (cdr form)
      (let ((opcode (get (car form) 'byte-opcode))
            args)
        (if (and (< 3 (length form))
                 (memq opcode (list (get '+ 'byte-opcode)
                                    (get '* 'byte-opcode))))
            ;; Don't use binary operations for > 2 operands, as that
            ;; may cause overflow/truncation in float operations.
            (byte-compile-normal-call form)
          (setq args (copy-sequence (cdr form)))
          (byte-compile-form (car args))
          (setq args (cdr args))
          (or args (setq args '(0)
                         opcode (get '+ 'byte-opcode)))
          (dolist (arg args)
            (byte-compile-form arg)
            (byte-compile-out opcode 0))))
    (byte-compile-constant (eval form))))

\f
;; more complicated compiler macros

(byte-defop-compiler char-before)
(byte-defop-compiler backward-char)
(byte-defop-compiler backward-word)
(byte-defop-compiler list)
(byte-defop-compiler concat)
(byte-defop-compiler fset)
(byte-defop-compiler (indent-to-column byte-indent-to) byte-compile-indent-to)
(byte-defop-compiler indent-to)
(byte-defop-compiler insert)
(byte-defop-compiler-1 function byte-compile-function-form)
(byte-defop-compiler-1 - byte-compile-minus)
(byte-defop-compiler (/ byte-quo) byte-compile-quo)
(byte-defop-compiler nconc)

;; Is this worth it?  Both -before and -after are written in C.
(defun byte-compile-char-before (form)
  (cond ((or (= 1 (length form))
             (and (= 2 (length form)) (not (nth 1 form))))
         (byte-compile-form '(char-after (1- (point)))))
        ((= 2 (length form))
         (byte-compile-form (list 'char-after (if (numberp (nth 1 form))
                                                  (1- (nth 1 form))
                                                `(1- (or ,(nth 1 form)
                                                         (point)))))))
        (t (byte-compile-subr-wrong-args form "0-1"))))

;; backward-... ==> forward-... with negated argument.
;; Is this worth it?  Both -backward and -forward are written in C.
(defun byte-compile-backward-char (form)
  (cond ((or (= 1 (length form))
             (and (= 2 (length form)) (not (nth 1 form))))
         (byte-compile-form '(forward-char -1)))
        ((= 2 (length form))
         (byte-compile-form (list 'forward-char (if (numberp (nth 1 form))
                                                    (- (nth 1 form))
                                                  `(- (or ,(nth 1 form) 1))))))
        (t (byte-compile-subr-wrong-args form "0-1"))))

(defun byte-compile-backward-word (form)
  (cond ((or (= 1 (length form))
             (and (= 2 (length form)) (not (nth 1 form))))
         (byte-compile-form '(forward-word -1)))
        ((= 2 (length form))
         (byte-compile-form (list 'forward-word (if (numberp (nth 1 form))
                                                    (- (nth 1 form))
                                                  `(- (or ,(nth 1 form) 1))))))
        (t (byte-compile-subr-wrong-args form "0-1"))))

(defun byte-compile-list (form)
  (let ((count (length (cdr form))))
    (cond ((= count 0)
           (byte-compile-constant nil))
          ((< count 5)
           (mapc 'byte-compile-form (cdr form))
           (byte-compile-out
            (aref [byte-list1 byte-list2 byte-list3 byte-list4] (1- count)) 0))
          ((< count 256)
           (mapc 'byte-compile-form (cdr form))
           (byte-compile-out 'byte-listN count))
          (t (byte-compile-normal-call form)))))

(defun byte-compile-concat (form)
  (let ((count (length (cdr form))))
    (cond ((and (< 1 count) (< count 5))
           (mapc 'byte-compile-form (cdr form))
           (byte-compile-out
            (aref [byte-concat2 byte-concat3 byte-concat4] (- count 2))
            0))
          ;; Concat of one arg is not a no-op if arg is not a string.
          ((= count 0)
           (byte-compile-form ""))
          ((< count 256)
           (mapc 'byte-compile-form (cdr form))
           (byte-compile-out 'byte-concatN count))
          ((byte-compile-normal-call form)))))

(defun byte-compile-minus (form)
  (let ((len (length form)))
    (cond
     ((= 1 len) (byte-compile-constant 0))
     ((= 2 len)
      (byte-compile-form (cadr form))
      (byte-compile-out 'byte-negate 0))
     ((= 3 len)
      (byte-compile-form (nth 1 form))
      (byte-compile-form (nth 2 form))
      (byte-compile-out 'byte-diff 0))
     ;; Don't use binary operations for > 2 operands, as that may
     ;; cause overflow/truncation in float operations.
     (t (byte-compile-normal-call form)))))

(defun byte-compile-quo (form)
  (let ((len (length form)))
    (cond ((< len 2)
           (byte-compile-subr-wrong-args form "1 or more"))
          ((= len 3)
           (byte-compile-two-args form))
          (t
           ;; Don't use binary operations for > 2 operands, as that
           ;; may cause overflow/truncation in float operations.
           (byte-compile-normal-call form)))))

(defun byte-compile-nconc (form)
  (let ((len (length form)))
    (cond ((= len 1)
           (byte-compile-constant nil))
          ((= len 2)
           ;; nconc of one arg is a noop, even if that arg isn't a list.
           (byte-compile-form (nth 1 form)))
          (t
           (byte-compile-form (car (setq form (cdr form))))
           (while (setq form (cdr form))
             (byte-compile-form (car form))
             (byte-compile-out 'byte-nconc 0))))))

(defun byte-compile-fset (form)
  ;; warn about forms like (fset 'foo '(lambda () ...))
  ;; (where the lambda expression is non-trivial...)
  (let ((fn (nth 2 form))
        body)
    (if (and (eq (car-safe fn) 'quote)
             (eq (car-safe (setq fn (nth 1 fn))) 'lambda))
        (progn
          (setq body (cdr (cdr fn)))
          (if (stringp (car body)) (setq body (cdr body)))
          (if (eq 'interactive (car-safe (car body))) (setq body (cdr body)))
          (if (and (consp (car body))
                   (not (eq 'byte-code (car (car body)))))
              (byte-compile-warn
      "A quoted lambda form is the second argument of `fset'.  This is probably
     not what you want, as that lambda cannot be compiled.  Consider using
     the syntax #'(lambda (...) ...) instead.")))))
  (byte-compile-two-args form))

;; (function foo) must compile like 'foo, not like (symbol-function 'foo).
;; Otherwise it will be incompatible with the interpreter,
;; and (funcall (function foo)) will lose with autoloads.

(defun byte-compile-function-form (form)
  (let ((f (nth 1 form)))
    (when (and (symbolp f)
               (byte-compile-warning-enabled-p 'callargs))
      (byte-compile-function-warn f t (byte-compile-fdefinition f nil)))

    (byte-compile-constant (if (eq 'lambda (car-safe f))
                               (byte-compile-lambda f)
                             f))))

(defun byte-compile-indent-to (form)
  (let ((len (length form)))
    (cond ((= len 2)
           (byte-compile-form (car (cdr form)))
           (byte-compile-out 'byte-indent-to 0))
          ((= len 3)
           ;; no opcode for 2-arg case.
           (byte-compile-normal-call form))
          (t
           (byte-compile-subr-wrong-args form "1-2")))))

(defun byte-compile-insert (form)
  (cond ((null (cdr form))
         (byte-compile-constant nil))
        ((<= (length form) 256)
         (mapc 'byte-compile-form (cdr form))
         (if (cdr (cdr form))
             (byte-compile-out 'byte-insertN (length (cdr form)))
           (byte-compile-out 'byte-insert 0)))
        ((memq t (mapcar 'consp (cdr (cdr form))))
         (byte-compile-normal-call form))
        ;; We can split it; there is no function call after inserting 1st arg.
        (t
         (while (setq form (cdr form))
           (byte-compile-form (car form))
           (byte-compile-out 'byte-insert 0)
           (if (cdr form)
               (byte-compile-discard))))))

\f
(byte-defop-compiler-1 setq)
(byte-defop-compiler-1 setq-default)
(byte-defop-compiler-1 quote)

(defun byte-compile-setq (form)
  (let* ((args (cdr form))
         (len (length args)))
    (if (= (logand len 1) 1)
        (progn
          (byte-compile-report-error
           (format-message
            "missing value for `%S' at end of setq" (car (last args))))
          (byte-compile-form
           `(signal 'wrong-number-of-arguments '(setq ,len))
           byte-compile--for-effect))
      (if args
          (while args
            (byte-compile-form (car (cdr args)))
            (or byte-compile--for-effect (cdr (cdr args))
                (byte-compile-out 'byte-dup 0))
            (byte-compile-variable-set (car args))
            (setq args (cdr (cdr args))))
        ;; (setq), with no arguments.
        (byte-compile-form nil byte-compile--for-effect)))
    (setq byte-compile--for-effect nil)))

(defun byte-compile-setq-default (form)
  (setq form (cdr form))
  (if (null form)                       ; (setq-default), with no arguments
      (byte-compile-form nil byte-compile--for-effect)
    (if (> (length form) 2)
        (let ((setters ()))
          (while (consp form)
            (push `(setq-default ,(pop form) ,(pop form)) setters))
          (byte-compile-form (cons 'progn (nreverse setters))))
      (let ((var (car form)))
        (and (or (not (symbolp var))
                 (macroexp--const-symbol-p var t))
             (byte-compile-warning-enabled-p 'constants)
             (byte-compile-warn
              "variable assignment to %s `%s'"
              (if (symbolp var) "constant" "nonvariable")
              (prin1-to-string var)))
        (byte-compile-normal-call `(set-default ',var ,@(cdr form)))))))

(byte-defop-compiler-1 set-default)
(defun byte-compile-set-default (form)
  (let ((varexp (car-safe (cdr-safe form))))
    (if (eq (car-safe varexp) 'quote)
        ;; If the varexp is constant, compile it as a setq-default
        ;; so we get more warnings.
        (byte-compile-setq-default `(setq-default ,(car-safe (cdr varexp))
                                                  ,@(cddr form)))
      (byte-compile-normal-call form))))

(defun byte-compile-quote (form)
  (byte-compile-constant (car (cdr form))))
\f
;;; control structures

(defun byte-compile-body (body &optional for-effect)
  (while (cdr body)
    (byte-compile-form (car body) t)
    (setq body (cdr body)))
  (byte-compile-form (car body) for-effect))

(defsubst byte-compile-body-do-effect (body)
  (byte-compile-body body byte-compile--for-effect)
  (setq byte-compile--for-effect nil))

(defsubst byte-compile-form-do-effect (form)
  (byte-compile-form form byte-compile--for-effect)
  (setq byte-compile--for-effect nil))

(byte-defop-compiler-1 inline byte-compile-progn)
(byte-defop-compiler-1 progn)
(byte-defop-compiler-1 prog1)
(byte-defop-compiler-1 prog2)
(byte-defop-compiler-1 if)
(byte-defop-compiler-1 cond)
(byte-defop-compiler-1 and)
(byte-defop-compiler-1 or)
(byte-defop-compiler-1 while)
(byte-defop-compiler-1 funcall)
(byte-defop-compiler-1 let)
(byte-defop-compiler-1 let* byte-compile-let)

(defun byte-compile-progn (form)
  (byte-compile-body-do-effect (cdr form)))

(defun byte-compile-prog1 (form)
  (byte-compile-form-do-effect (car (cdr form)))
  (byte-compile-body (cdr (cdr form)) t))

(defun byte-compile-prog2 (form)
  (byte-compile-form (nth 1 form) t)
  (byte-compile-form-do-effect (nth 2 form))
  (byte-compile-body (cdr (cdr (cdr form))) t))

(defmacro byte-compile-goto-if (cond discard tag)
  `(byte-compile-goto
    (if ,cond
        (if ,discard 'byte-goto-if-not-nil 'byte-goto-if-not-nil-else-pop)
      (if ,discard 'byte-goto-if-nil 'byte-goto-if-nil-else-pop))
    ,tag))

;; Return the list of items in CONDITION-PARAM that match PRED-LIST.
;; Only return items that are not in ONLY-IF-NOT-PRESENT.
(defun byte-compile-find-bound-condition (condition-param
                                          pred-list
                                          &optional only-if-not-present)
  (let ((result nil)
        (nth-one nil)
        (cond-list
         (if (memq (car-safe condition-param) pred-list)
             ;; The condition appears by itself.
             (list condition-param)
           ;; If the condition is an `and', look for matches among the
           ;; `and' arguments.
           (when (eq 'and (car-safe condition-param))
             (cdr condition-param)))))

    (dolist (crt cond-list)
      (when (and (memq (car-safe crt) pred-list)
                 (eq 'quote (car-safe (setq nth-one (nth 1 crt))))
                 ;; Ignore if the symbol is already on the unresolved
                 ;; list.
                 (not (assq (nth 1 nth-one) ; the relevant symbol
                            only-if-not-present)))
        (push (nth 1 (nth 1 crt)) result)))
    result))

(defmacro byte-compile-maybe-guarded (condition &rest body)
  "Execute forms in BODY, potentially guarded by CONDITION.
CONDITION is a variable whose value is a test in an `if' or `cond'.
BODY is the code to compile in the first arm of the if or the body of
the cond clause.  If CONDITION's value is of the form (fboundp \\='foo)
or (boundp \\='foo), the relevant warnings from BODY about foo's
being undefined (or obsolete) will be suppressed.

If CONDITION's value is (not (featurep \\='emacs)) or (featurep \\='xemacs),
that suppresses all warnings during execution of BODY."
  (declare (indent 1) (debug t))
  `(let* ((fbound-list (byte-compile-find-bound-condition
                        ,condition '(fboundp functionp)
                        byte-compile-unresolved-functions))
          (bound-list (byte-compile-find-bound-condition
                       ,condition '(boundp default-boundp)))
          ;; Maybe add to the bound list.
          (byte-compile-bound-variables
           (append bound-list byte-compile-bound-variables)))
     (unwind-protect
         ;; If things not being bound at all is ok, so must them being
         ;; obsolete.  Note that we add to the existing lists since Tramp
         ;; (ab)uses this feature.
         ;; FIXME: If `foo' is obsoleted by `bar', the code below
         ;; correctly arranges to silence the warnings after testing
         ;; existence of `foo', but the warning should also be
         ;; silenced after testing the existence of `bar'.
         (let ((byte-compile-not-obsolete-vars
                (append byte-compile-not-obsolete-vars bound-list))
               (byte-compile-not-obsolete-funcs
                (append byte-compile-not-obsolete-funcs fbound-list)))
           ,@body)
       ;; Maybe remove the function symbol from the unresolved list.
       (dolist (fbound fbound-list)
         (when fbound
           (setq byte-compile-unresolved-functions
                 (delq (assq fbound byte-compile-unresolved-functions)
                       byte-compile-unresolved-functions)))))))

(defun byte-compile-if (form)
  (byte-compile-form (car (cdr form)))
  ;; Check whether we have `(if (fboundp ...' or `(if (boundp ...'
  ;; and avoid warnings about the relevant symbols in the consequent.
  (let ((clause (nth 1 form))
        (donetag (byte-compile-make-tag)))
    (if (null (nthcdr 3 form))
        ;; No else-forms
        (progn
          (byte-compile-goto-if nil byte-compile--for-effect donetag)
          (byte-compile-maybe-guarded clause
            (byte-compile-form (nth 2 form) byte-compile--for-effect))
          (byte-compile-out-tag donetag))
      (let ((elsetag (byte-compile-make-tag)))
        (byte-compile-goto 'byte-goto-if-nil elsetag)
        (byte-compile-maybe-guarded clause
          (byte-compile-form (nth 2 form) byte-compile--for-effect))
        (byte-compile-goto 'byte-goto donetag)
        (byte-compile-out-tag elsetag)
        (byte-compile-maybe-guarded (list 'not clause)
          (byte-compile-body (cdr (cdr (cdr form))) byte-compile--for-effect))
        (byte-compile-out-tag donetag))))
  (setq byte-compile--for-effect nil))

(defun byte-compile-cond-vars (obj1 obj2)
  ;; We make sure that of OBJ1 and OBJ2, one of them is a symbol,
  ;; and the other is a constant expression whose value can be
  ;; compared with `eq' (with `macroexp-const-p').
  (or
   (and (symbolp obj1) (macroexp-const-p obj2) (cons obj1 obj2))
   (and (symbolp obj2) (macroexp-const-p obj1) (cons obj2 obj1))))

(defun byte-compile-cond-jump-table-info (clauses)
  "If CLAUSES is a `cond' form where:
The condition for each clause is of the form (TEST VAR VALUE).
VAR is a variable.
TEST and VAR are the same throughout all conditions.
VALUE satisfies `macroexp-const-p'.

Return a list of the form ((TEST . VAR)  ((VALUE BODY) ...))"
  (let ((cases '())
        (ok t)
        prev-var prev-test)
    (and (catch 'break
           (dolist (clause (cdr clauses) ok)
             (let* ((condition (car clause))
                    (test (car-safe condition))
                    (vars (when (consp condition)
                            (byte-compile-cond-vars (cadr condition) (cl-caddr condition))))
                    (obj1 (car-safe vars))
                    (obj2 (cdr-safe vars))
                    (body (cdr-safe clause)))
               (unless prev-var
                 (setq prev-var obj1))
               (unless prev-test
                 (setq prev-test test))
               (if (and obj1 (memq test '(eq eql equal))
                        (consp condition)
                        (eq test prev-test)
                        (eq obj1 prev-var)
                        ;; discard duplicate clauses
                        (not (assq obj2 cases)))
                   (push (list (if (consp obj2) (eval obj2) obj2) body) cases)
                 (if (eq condition t)
                     (progn (push (list 'default body) cases)
                            (throw 'break t))
                   (setq ok nil)
                   (throw 'break nil))))))
         (list (cons prev-test prev-var) (nreverse cases)))))

(defun byte-compile-cond-jump-table (clauses)
  (let* ((table-info (byte-compile-cond-jump-table-info clauses))
         (test (caar table-info))
         (var (cdar table-info))
         (cases (cadr table-info))
         jump-table test-obj body tag donetag default-tag default-case)
    (when (and cases (not (= (length cases) 1)))
      ;; TODO: Once :linear-search is implemented for `make-hash-table'
      ;; set it to `t' for cond forms with a small number of cases.
      (setq jump-table (make-hash-table :test test
                                        :purecopy t
                                        :size (if (assq 'default cases)
                                                  (1- (length cases))
                                                (length cases)))
            default-tag (byte-compile-make-tag)
            donetag (byte-compile-make-tag))
      ;; The structure of byte-switch code:
      ;;
      ;; varref var
      ;; constant #s(hash-table purecopy t data (val1 (TAG1) val2 (TAG2)))
      ;; switch
      ;; goto DEFAULT-TAG
      ;; TAG1
      ;; <clause body>
      ;; goto DONETAG
      ;; TAG2
      ;; <clause body>
      ;; goto DONETAG
      ;; DEFAULT-TAG
      ;; <body for `t' clause, if any (else `constant nil')>
      ;; DONETAG

      (byte-compile-variable-ref var)
      (byte-compile-push-constant jump-table)
      (byte-compile-out 'byte-switch)

      ;; When the opcode argument is `byte-goto', `byte-compile-goto' sets
      ;; `byte-compile-depth' to `nil'. However, we need `byte-compile-depth'
      ;; to be non-nil for generating tags for all cases. Since
      ;; `byte-compile-depth' will increase by at most 1 after compiling
      ;; all of the clause (which is further enforced by cl-assert below)
      ;; it should be safe to preserve it's value.
      (let ((byte-compile-depth byte-compile-depth))
        (byte-compile-goto 'byte-goto default-tag))

      (when (assq 'default cases)
        (setq default-case (cadr (assq 'default cases))
              cases (butlast cases 1)))

      (dolist (case cases)
        (setq tag (byte-compile-make-tag)
              test-obj (nth 0 case)
              body (nth 1 case))
        (byte-compile-out-tag tag)
        (puthash test-obj tag jump-table)

        (let ((byte-compile-depth byte-compile-depth)
              (init-depth byte-compile-depth))
          ;; Since `byte-compile-body' might increase `byte-compile-depth'
          ;; by 1, not preserving it's value will cause it to potentially
          ;; increase by one for every clause body compiled, causing
          ;; depth/tag conflicts or violating asserts down the road.
          ;; To make sure `byte-compile-body' itself doesn't violate this,
          ;; we use `cl-assert'.
          (byte-compile-body body byte-compile--for-effect)
          (cl-assert (or (= byte-compile-depth init-depth)
                         (= byte-compile-depth (1+ init-depth))))
          (byte-compile-goto 'byte-goto donetag)
          (setcdr (cdr donetag) nil)))

      (byte-compile-out-tag default-tag)
      (if default-case
          (byte-compile-body-do-effect default-case)
        (byte-compile-constant nil))
      (byte-compile-out-tag donetag)
      (push jump-table byte-compile-jump-tables))))

(defun byte-compile-cond (clauses)
  (or (and byte-compile-cond-use-jump-table
           (byte-compile-cond-jump-table clauses))
    (let ((donetag (byte-compile-make-tag))
          nexttag clause)
      (while (setq clauses (cdr clauses))
        (setq clause (car clauses))
        (cond ((or (eq (car clause) t)
                   (and (eq (car-safe (car clause)) 'quote)
                        (car-safe (cdr-safe (car clause)))))
               ;; Unconditional clause
               (setq clause (cons t clause)
                     clauses nil))
              ((cdr clauses)
               (byte-compile-form (car clause))
               (if (null (cdr clause))
                   ;; First clause is a singleton.
                   (byte-compile-goto-if t byte-compile--for-effect donetag)
                 (setq nexttag (byte-compile-make-tag))
                 (byte-compile-goto 'byte-goto-if-nil nexttag)
                 (byte-compile-maybe-guarded (car clause)
                   (byte-compile-body (cdr clause) byte-compile--for-effect))
                 (byte-compile-goto 'byte-goto donetag)
                 (byte-compile-out-tag nexttag)))))
      ;; Last clause
      (let ((guard (car clause)))
        (and (cdr clause) (not (eq guard t))
             (progn (byte-compile-form guard)
                    (byte-compile-goto-if nil byte-compile--for-effect donetag)
                    (setq clause (cdr clause))))
        (byte-compile-maybe-guarded guard
          (byte-compile-body-do-effect clause)))
      (byte-compile-out-tag donetag))))

(defun byte-compile-and (form)
  (let ((failtag (byte-compile-make-tag))
        (args (cdr form)))
    (if (null args)
        (byte-compile-form-do-effect t)
      (byte-compile-and-recursion args failtag))))

;; Handle compilation of a nontrivial `and' call.
;; We use tail recursion so we can use byte-compile-maybe-guarded.
(defun byte-compile-and-recursion (rest failtag)
  (if (cdr rest)
      (progn
        (byte-compile-form (car rest))
        (byte-compile-goto-if nil byte-compile--for-effect failtag)
        (byte-compile-maybe-guarded (car rest)
          (byte-compile-and-recursion (cdr rest) failtag)))
    (byte-compile-form-do-effect (car rest))
    (byte-compile-out-tag failtag)))

(defun byte-compile-or (form)
  (let ((wintag (byte-compile-make-tag))
        (args (cdr form)))
    (if (null args)
        (byte-compile-form-do-effect nil)
      (byte-compile-or-recursion args wintag))))

;; Handle compilation of a nontrivial `or' call.
;; We use tail recursion so we can use byte-compile-maybe-guarded.
(defun byte-compile-or-recursion (rest wintag)
  (if (cdr rest)
      (progn
        (byte-compile-form (car rest))
        (byte-compile-goto-if t byte-compile--for-effect wintag)
        (byte-compile-maybe-guarded (list 'not (car rest))
          (byte-compile-or-recursion (cdr rest) wintag)))
    (byte-compile-form-do-effect (car rest))
    (byte-compile-out-tag wintag)))

(defun byte-compile-while (form)
  (let ((endtag (byte-compile-make-tag))
        (looptag (byte-compile-make-tag)))
    (byte-compile-out-tag looptag)
    (byte-compile-form (car (cdr form)))
    (byte-compile-goto-if nil byte-compile--for-effect endtag)
    (byte-compile-body (cdr (cdr form)) t)
    (byte-compile-goto 'byte-goto looptag)
    (byte-compile-out-tag endtag)
    (setq byte-compile--for-effect nil)))

(defun byte-compile-funcall (form)
  (if (cdr form)
      (progn
        (mapc 'byte-compile-form (cdr form))
        (byte-compile-out 'byte-call (length (cdr (cdr form)))))
    (byte-compile-report-error
     (format-message "`funcall' called with no arguments"))
    (byte-compile-form '(signal 'wrong-number-of-arguments '(funcall 0))
                       byte-compile--for-effect)))

\f
;; let binding

(defun byte-compile-push-binding-init (clause)
  "Emit byte-codes to push the initialization value for CLAUSE on the stack.
Return the offset in the form (VAR . OFFSET)."
  (let* ((var (if (consp clause) (car clause) clause)))
    ;; We record the stack position even of dynamic bindings; we'll put
    ;; them in the proper place later.
    (prog1 (cons var byte-compile-depth)
      (if (consp clause)
          (byte-compile-form (cadr clause))
        (byte-compile-push-constant nil)))))

(defun byte-compile-not-lexical-var-p (var)
  (or (not (symbolp var))
      (special-variable-p var)
      (memq var byte-compile-bound-variables)
      (memq var '(nil t))
      (keywordp var)))

(defun byte-compile-bind (var init-lexenv)
  "Emit byte-codes to bind VAR and update `byte-compile--lexical-environment'.
INIT-LEXENV should be a lexical-environment alist describing the
positions of the init value that have been pushed on the stack.
Return non-nil if the TOS value was popped."
  ;; The mix of lexical and dynamic bindings mean that we may have to
  ;; juggle things on the stack, to move them to TOS for
  ;; dynamic binding.
  (if (and lexical-binding (not (byte-compile-not-lexical-var-p var)))
      ;; VAR is a simple stack-allocated lexical variable.
      (progn (push (assq var init-lexenv)
                   byte-compile--lexical-environment)
             nil)
    ;; VAR should be dynamically bound.
    (while (assq var byte-compile--lexical-environment)
      ;; This dynamic binding shadows a lexical binding.
      (setq byte-compile--lexical-environment
            (remq (assq var byte-compile--lexical-environment)
                  byte-compile--lexical-environment)))
    (cond
     ((eq var (caar init-lexenv))
      ;; VAR is dynamic and is on the top of the
      ;; stack, so we can just bind it like usual.
      (byte-compile-dynamic-variable-bind var)
      t)
     (t
      ;; VAR is dynamic, but we have to get its
      ;; value out of the middle of the stack.
      (let ((stack-pos (cdr (assq var init-lexenv))))
        (byte-compile-stack-ref stack-pos)
        (byte-compile-dynamic-variable-bind var)
        ;; Now we have to store nil into its temporary
        ;; stack position so it doesn't prevent the value from being GC'd.
        ;; FIXME: Not worth the trouble.
        ;; (byte-compile-push-constant nil)
        ;; (byte-compile-stack-set stack-pos)
        )
      nil))))

(defun byte-compile-unbind (clauses init-lexenv preserve-body-value)
  "Emit byte-codes to unbind the variables bound by CLAUSES.
CLAUSES is a `let'-style variable binding list.  INIT-LEXENV should be a
lexical-environment alist describing the positions of the init value that
have been pushed on the stack.  If PRESERVE-BODY-VALUE is true,
then an additional value on the top of the stack, above any lexical binding
slots, is preserved, so it will be on the top of the stack after all
binding slots have been popped."
  ;; Unbind dynamic variables.
  (let ((num-dynamic-bindings 0))
    (dolist (clause clauses)
      (unless (assq (if (consp clause) (car clause) clause)
                    byte-compile--lexical-environment)
        (setq num-dynamic-bindings (1+ num-dynamic-bindings))))
    (unless (zerop num-dynamic-bindings)
      (byte-compile-out 'byte-unbind num-dynamic-bindings)))
  ;; Pop lexical variables off the stack, possibly preserving the
  ;; return value of the body.
  (when init-lexenv
    ;; INIT-LEXENV contains all init values left on the stack.
    (byte-compile-discard (length init-lexenv) preserve-body-value)))

(defun byte-compile-let (form)
  "Generate code for the `let' or `let*' form FORM."
  (let ((clauses (cadr form))
        (init-lexenv nil)
        (is-let (eq (car form) 'let)))
    (when is-let
      ;; First compute the binding values in the old scope.
      (dolist (var clauses)
        (push (byte-compile-push-binding-init var) init-lexenv)))
    ;; New scope.
    (let ((byte-compile-bound-variables byte-compile-bound-variables)
          (byte-compile--lexical-environment
           byte-compile--lexical-environment))
      ;; Bind the variables.
      ;; For `let', do it in reverse order, because it makes no
      ;; semantic difference, but it is a lot more efficient since the
      ;; values are now in reverse order on the stack.
      (dolist (var (if is-let (reverse clauses) clauses))
        (unless is-let
          (push (byte-compile-push-binding-init var) init-lexenv))
        (let ((var (if (consp var) (car var) var)))
          (if (byte-compile-bind var init-lexenv)
              (pop init-lexenv))))
      ;; Emit the body.
      (let ((init-stack-depth byte-compile-depth))
        (byte-compile-body-do-effect (cdr (cdr form)))
        ;; Unbind both lexical and dynamic variables.
        (cl-assert (or (eq byte-compile-depth init-stack-depth)
                       (eq byte-compile-depth (1+ init-stack-depth))))
        (byte-compile-unbind clauses init-lexenv
                             (> byte-compile-depth init-stack-depth))))))

\f

(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>)
  (byte-compile-set-symbol-position (car form))
  (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))))
\f
;;; other tricky macro-like special-forms

(byte-defop-compiler-1 catch)
(byte-defop-compiler-1 unwind-protect)
(byte-defop-compiler-1 condition-case)
(byte-defop-compiler-1 save-excursion)
(byte-defop-compiler-1 save-current-buffer)
(byte-defop-compiler-1 save-restriction)
;; (byte-defop-compiler-1 save-window-excursion)      ;Obsolete: now a macro.
;; (byte-defop-compiler-1 with-output-to-temp-buffer) ;Obsolete: now a macro.

(defvar byte-compile--use-old-handlers nil
  "If nil, use new byte codes introduced in Emacs-24.4.")

(defun byte-compile-catch (form)
  (byte-compile-form (car (cdr form)))
  (if (not byte-compile--use-old-handlers)
      (let ((endtag (byte-compile-make-tag)))
        (byte-compile-goto 'byte-pushcatch endtag)
        (byte-compile-body (cddr form) nil)
        (byte-compile-out 'byte-pophandler)
        (byte-compile-out-tag endtag))
    (pcase (cddr form)
      (`(:fun-body ,f)
       (byte-compile-form `(list 'funcall ,f)))
      (body
       (byte-compile-push-constant
        (byte-compile-top-level (cons 'progn body) byte-compile--for-effect))))
    (byte-compile-out 'byte-catch 0)))

(defun byte-compile-unwind-protect (form)
  (pcase (cddr form)
    (`(:fun-body ,f)
     (byte-compile-form
      (if byte-compile--use-old-handlers `(list (list 'funcall ,f)) f)))
    (handlers
     (if byte-compile--use-old-handlers
         (byte-compile-push-constant
          (byte-compile-top-level-body handlers t))
       (byte-compile-form `#'(lambda () ,@handlers)))))
  (byte-compile-out 'byte-unwind-protect 0)
  (byte-compile-form-do-effect (car (cdr form)))
  (byte-compile-out 'byte-unbind 1))

(defun byte-compile-condition-case (form)
  (if byte-compile--use-old-handlers
      (byte-compile-condition-case--old form)
    (byte-compile-condition-case--new form)))

(defun byte-compile-condition-case--old (form)
  (let* ((var (nth 1 form))
         (fun-bodies (eq var :fun-body))
         (byte-compile-bound-variables
          (if (and var (not fun-bodies))
              (cons var byte-compile-bound-variables)
            byte-compile-bound-variables)))
    (byte-compile-set-symbol-position 'condition-case)
    (unless (symbolp var)
      (byte-compile-warn
       "`%s' is not a variable-name or nil (in condition-case)" var))
    (if fun-bodies (setq var (make-symbol "err")))
    (byte-compile-push-constant var)
    (if fun-bodies
        (byte-compile-form `(list 'funcall ,(nth 2 form)))
      (byte-compile-push-constant
       (byte-compile-top-level (nth 2 form) byte-compile--for-effect)))
    (let ((compiled-clauses
           (mapcar
            (lambda (clause)
              (let ((condition (car clause)))
                (cond ((not (or (symbolp condition)
                                (and (listp condition)
                                     (let ((ok t))
                                       (dolist (sym condition)
                                         (if (not (symbolp sym))
                                             (setq ok nil)))
                                       ok))))
                       (byte-compile-warn
                        "`%S' is not a condition name or list of such (in condition-case)"
                        condition))
                      ;; (not (or (eq condition 't)
                      ;;         (and (stringp (get condition 'error-message))
                      ;;              (consp (get condition
                      ;;                          'error-conditions)))))
                      ;; (byte-compile-warn
                      ;;   "`%s' is not a known condition name
                      ;;   (in condition-case)"
                      ;;   condition))
                      )
                (if fun-bodies
                    `(list ',condition (list 'funcall ,(cadr clause) ',var))
                  (cons condition
                        (byte-compile-top-level-body
                         (cdr clause) byte-compile--for-effect)))))
            (cdr (cdr (cdr form))))))
      (if fun-bodies
          (byte-compile-form `(list ,@compiled-clauses))
        (byte-compile-push-constant compiled-clauses)))
    (byte-compile-out 'byte-condition-case 0)))

(defun byte-compile-condition-case--new (form)
  (let* ((var (nth 1 form))
         (body (nth 2 form))
         (depth byte-compile-depth)
         (clauses (mapcar (lambda (clause)
                            (cons (byte-compile-make-tag) clause))
                          (nthcdr 3 form)))
         (endtag (byte-compile-make-tag)))
    (byte-compile-set-symbol-position 'condition-case)
    (unless (symbolp var)
      (byte-compile-warn
       "`%s' is not a variable-name or nil (in condition-case)" var))

    (dolist (clause (reverse clauses))
      (let ((condition (nth 1 clause)))
        (unless (consp condition) (setq condition (list condition)))
        (dolist (c condition)
          (unless (and c (symbolp c))
            (byte-compile-warn
             "`%S' is not a condition name (in condition-case)" c))
          ;; In reality, the `error-conditions' property is only required
          ;; for the argument to `signal', not to `condition-case'.
          ;;(unless (consp (get c 'error-conditions))
          ;;  (byte-compile-warn
          ;;   "`%s' is not a known condition name (in condition-case)"
          ;;   c))
          )
        (byte-compile-push-constant condition))
      (byte-compile-goto 'byte-pushconditioncase (car clause)))

    (byte-compile-form body) ;; byte-compile--for-effect
    (dolist (_ clauses) (byte-compile-out 'byte-pophandler))
    (byte-compile-goto 'byte-goto endtag)

    (while clauses
      (let ((clause (pop clauses))
            (byte-compile-bound-variables byte-compile-bound-variables)
            (byte-compile--lexical-environment
             byte-compile--lexical-environment))
        (setq byte-compile-depth (1+ depth))
        (byte-compile-out-tag (pop clause))
        (dolist (_ clauses) (byte-compile-out 'byte-pophandler))
        (cond
         ((null var) (byte-compile-discard))
         (lexical-binding
          (push (cons var (1- byte-compile-depth))
                byte-compile--lexical-environment))
         (t (byte-compile-dynamic-variable-bind var)))
        (byte-compile-body (cdr clause)) ;; byte-compile--for-effect
        (cond
         ((null var) nil)
         (lexical-binding (byte-compile-discard 1 'preserve-tos))
         (t (byte-compile-out 'byte-unbind 1)))
        (byte-compile-goto 'byte-goto endtag)))

    (byte-compile-out-tag endtag)))

(defun byte-compile-save-excursion (form)
  (if (and (eq 'set-buffer (car-safe (car-safe (cdr form))))
           (byte-compile-warning-enabled-p 'suspicious))
      (byte-compile-warn
       "Use `with-current-buffer' rather than save-excursion+set-buffer"))
  (byte-compile-out 'byte-save-excursion 0)
  (byte-compile-body-do-effect (cdr form))
  (byte-compile-out 'byte-unbind 1))

(defun byte-compile-save-restriction (form)
  (byte-compile-out 'byte-save-restriction 0)
  (byte-compile-body-do-effect (cdr form))
  (byte-compile-out 'byte-unbind 1))

(defun byte-compile-save-current-buffer (form)
  (byte-compile-out 'byte-save-current-buffer 0)
  (byte-compile-body-do-effect (cdr form))
  (byte-compile-out 'byte-unbind 1))
\f
;;; top-level forms elsewhere

(byte-defop-compiler-1 defvar)
(byte-defop-compiler-1 defconst byte-compile-defvar)
(byte-defop-compiler-1 autoload)
(byte-defop-compiler-1 lambda byte-compile-lambda-form)

;; If foo.el declares `toto' as obsolete, it is likely that foo.el will
;; actually use `toto' in order for this obsolete variable to still work
;; correctly, so paradoxically, while byte-compiling foo.el, the presence
;; of a make-obsolete-variable call for `toto' is an indication that `toto'
;; should not trigger obsolete-warnings in foo.el.
(byte-defop-compiler-1 make-obsolete-variable)
(defun byte-compile-make-obsolete-variable (form)
  (when (eq 'quote (car-safe (nth 1 form)))
    (push (nth 1 (nth 1 form)) byte-compile-global-not-obsolete-vars))
  (byte-compile-normal-call form))

(defconst byte-compile-tmp-var (make-symbol "def-tmp-var"))

(defun byte-compile-defvar (form)
  ;; This is not used for file-level defvar/consts.
  (when (and (symbolp (nth 1 form))
             (not (string-match "[-*/:$]" (symbol-name (nth 1 form))))
             (byte-compile-warning-enabled-p 'lexical))
    (byte-compile-warn "global/dynamic var `%s' lacks a prefix"
                       (nth 1 form)))
  (let ((fun (nth 0 form))
        (var (nth 1 form))
        (value (nth 2 form))
        (string (nth 3 form)))
    (byte-compile-set-symbol-position fun)
    (when (or (> (length form) 4)
              (and (eq fun 'defconst) (null (cddr form))))
      (let ((ncall (length (cdr form))))
        (byte-compile-warn
         "`%s' called with %d argument%s, but %s %s"
         fun ncall
         (if (= 1 ncall) "" "s")
         (if (< ncall 2) "requires" "accepts only")
         "2-3")))
    (push var byte-compile-bound-variables)
    (if (eq fun 'defconst)
        (push var byte-compile-const-variables))
    (when (and string (not (stringp string)))
      (byte-compile-warn "third arg to `%s %s' is not a string: %s"
                         fun var string))
    (byte-compile-form-do-effect
     (if (cddr form)  ; `value' provided
         ;; Quote with `quote' to prevent byte-compiling the body,
         ;; which would lead to an inf-loop.
         `(funcall '(lambda (,byte-compile-tmp-var)
                      (,fun ,var ,byte-compile-tmp-var ,@(nthcdr 3 form)))
                   ,value)
        (if (eq fun 'defconst)
            ;; This will signal an appropriate error at runtime.
            `(eval ',form)
          ;; A simple (defvar foo) just returns foo.
          `',var)))))

(defun byte-compile-autoload (form)
  (byte-compile-set-symbol-position 'autoload)
  (and (macroexp-const-p (nth 1 form))
       (macroexp-const-p (nth 5 form))
       (memq (eval (nth 5 form)) '(t macro))  ; macro-p
       (not (fboundp (eval (nth 1 form))))
       (byte-compile-warn
        "The compiler ignores `autoload' except at top level.  You should
     probably put the autoload of the macro `%s' at top-level."
        (eval (nth 1 form))))
  (byte-compile-normal-call form))

;; Lambdas in valid places are handled as special cases by various code.
;; The ones that remain are errors.
(defun byte-compile-lambda-form (_form)
  (byte-compile-set-symbol-position 'lambda)
  (error "`lambda' used as function name is invalid"))

;; Compile normally, but deal with warnings for the function being defined.
(put 'defalias 'byte-hunk-handler 'byte-compile-file-form-defalias)
;; Used for eieio--defalias as well.
(defun byte-compile-file-form-defalias (form)
  ;; For the compilation itself, we could largely get rid of this hunk-handler,
  ;; if it weren't for the fact that we need to figure out when a defalias
  ;; defines a macro, so as to add it to byte-compile-macro-environment.
  ;;
  ;; FIXME: we also use this hunk-handler to implement the function's dynamic
  ;; docstring feature.  We could actually implement it more elegantly in
  ;; byte-compile-lambda so it applies to all lambdas, but the problem is that
  ;; the resulting .elc format will not be recognized by make-docfile, so
  ;; either we stop using DOC for the docstrings of preloaded elc files (at the
  ;; cost of around 24KB on 32bit hosts, double on 64bit hosts) or we need to
  ;; build DOC in a more clever way (e.g. handle anonymous elements).
  (let ((byte-compile-free-references nil)
        (byte-compile-free-assignments nil))
    (pcase form
      ;; Decompose `form' into:
      ;; - `name' is the name of the defined function.
      ;; - `arg' is the expression to which it is defined.
      ;; - `rest' is the rest of the arguments.
      (`(,_ ',name ,arg . ,rest)
       (pcase-let*
           ;; `macro' is non-nil if it defines a macro.
           ;; `fun' is the function part of `arg' (defaults to `arg').
           (((or (and (or `(cons 'macro ,fun) `'(macro . ,fun)) (let macro t))
                 (and (let fun arg) (let macro nil)))
             arg)
            ;; `lam' is the lambda expression in `fun' (or nil if not
            ;; recognized).
            ((or `(,(or `quote `function) ,lam) (let lam nil))
             fun)
            ;; `arglist' is the list of arguments (or t if not recognized).
            ;; `body' is the body of `lam' (or t if not recognized).
            ((or `(lambda ,arglist . ,body)
                 ;; `(closure ,_ ,arglist . ,body)
                 (and `(internal-make-closure ,arglist . ,_) (let body t))
                 (and (let arglist t) (let body t)))
             lam))
         (unless (byte-compile-file-form-defmumble
                  name macro arglist body rest)
           (when macro
             (if (null fun)
                 (message "Macro %s unrecognized, won't work in file" name)
               (message "Macro %s partly recognized, trying our luck" name)
               (push (cons name (eval fun))
                     byte-compile-macro-environment)))
           (byte-compile-keep-pending form))))

      ;; We used to just do: (byte-compile-normal-call form)
      ;; But it turns out that this fails to optimize the code.
      ;; So instead we now do the same as what other byte-hunk-handlers do,
      ;; which is to call back byte-compile-file-form and then return nil.
      ;; Except that we can't just call byte-compile-file-form since it would
      ;; call us right back.
      (_ (byte-compile-keep-pending form)))))

(byte-defop-compiler-1 with-no-warnings byte-compile-no-warnings)
(defun byte-compile-no-warnings (form)
  (let (byte-compile-warnings)
    (byte-compile-form (cons 'progn (cdr form)))))

;; Warn about misuses of make-variable-buffer-local.
(byte-defop-compiler-1 make-variable-buffer-local
                       byte-compile-make-variable-buffer-local)
(defun byte-compile-make-variable-buffer-local (form)
  (if (and (eq (car-safe (car-safe (cdr-safe form))) 'quote)
           (byte-compile-warning-enabled-p 'make-local))
      (byte-compile-warn
       "`make-variable-buffer-local' not called at toplevel"))
  (byte-compile-normal-call form))
(put 'make-variable-buffer-local
     'byte-hunk-handler 'byte-compile-form-make-variable-buffer-local)
(defun byte-compile-form-make-variable-buffer-local (form)
  (byte-compile-keep-pending form 'byte-compile-normal-call))
\f
;;; tags

;; Note: Most operations will strip off the 'TAG, but it speeds up
;; optimization to have the 'TAG as a part of the tag.
;; Tags will be (TAG . (tag-number . stack-depth)).
(defun byte-compile-make-tag ()
  (list 'TAG (setq byte-compile-tag-number (1+ byte-compile-tag-number))))


(defun byte-compile-out-tag (tag)
  (setq byte-compile-output (cons tag byte-compile-output))
  (if (cdr (cdr tag))
      (progn
        ;; ## remove this someday
        (and byte-compile-depth
             (not (= (cdr (cdr tag)) byte-compile-depth))
             (error "Compiler bug: depth conflict at tag %d" (car (cdr tag))))
        (setq byte-compile-depth (cdr (cdr tag))))
    (setcdr (cdr tag) byte-compile-depth)))

(defun byte-compile-goto (opcode tag)
  (push (cons opcode tag) byte-compile-output)
  (setcdr (cdr tag) (if (memq opcode byte-goto-always-pop-ops)
                        (1- byte-compile-depth)
                      byte-compile-depth))
  (setq byte-compile-depth (and (not (eq opcode 'byte-goto))
                                (1- byte-compile-depth))))

(defun byte-compile-stack-adjustment (op operand)
  "Return the amount by which an operation adjusts the stack.
OP and OPERAND are as passed to `byte-compile-out'."
  (if (memq op '(byte-call byte-discardN byte-discardN-preserve-tos))
      ;; For calls, OPERAND is the number of args, so we pop OPERAND + 1
      ;; elements, and the push the result, for a total of -OPERAND.
      ;; For discardN*, of course, we just pop OPERAND elements.
      (- operand)
    (or (aref byte-stack+-info (symbol-value op))
        ;; Ops with a nil entry in `byte-stack+-info' are byte-codes
        ;; that take OPERAND values off the stack and push a result, for
        ;; a total of 1 - OPERAND
        (- 1 operand))))

(defun byte-compile-out (op &optional operand)
  (push (cons op operand) byte-compile-output)
  (if (eq op 'byte-return)
      ;; This is actually an unnecessary case, because there should be no
      ;; more ops behind byte-return.
      (setq byte-compile-depth nil)
    (setq byte-compile-depth
          (+ byte-compile-depth (byte-compile-stack-adjustment op operand)))
    (setq byte-compile-maxdepth (max byte-compile-depth byte-compile-maxdepth))
    ;;(if (< byte-compile-depth 0) (error "Compiler error: stack underflow"))
    ))
\f
;;; call tree stuff

(defun byte-compile-annotate-call-tree (form)
  (let (entry)
    ;; annotate the current call
    (if (setq entry (assq (car form) byte-compile-call-tree))
        (or (memq byte-compile-current-form (nth 1 entry)) ;callers
            (setcar (cdr entry)
                    (cons byte-compile-current-form (nth 1 entry))))
      (setq byte-compile-call-tree
            (cons (list (car form) (list byte-compile-current-form) nil)
                  byte-compile-call-tree)))
    ;; annotate the current function
    (if (setq entry (assq byte-compile-current-form byte-compile-call-tree))
        (or (memq (car form) (nth 2 entry)) ;called
            (setcar (cdr (cdr entry))
                    (cons (car form) (nth 2 entry))))
      (setq byte-compile-call-tree
            (cons (list byte-compile-current-form nil (list (car form)))
                  byte-compile-call-tree)))
    ))

;; Renamed from byte-compile-report-call-tree
;; to avoid interfering with completion of byte-compile-file.
;;;###autoload
(defun display-call-tree (&optional filename)
  "Display a call graph of a specified file.
This lists which functions have been called, what functions called
them, and what functions they call.  The list includes all functions
whose definitions have been compiled in this Emacs session, as well as
all functions called by those functions.

The call graph does not include macros, inline functions, or
primitives that the byte-code interpreter knows about directly
\(`eq', `cons', etc.).

The call tree also lists those functions which are not known to be called
\(that is, to which no calls have been compiled), and which cannot be
invoked interactively."
  (interactive)
  (message "Generating call tree...")
  (with-output-to-temp-buffer "*Call-Tree*"
    (set-buffer "*Call-Tree*")
    (erase-buffer)
    (message "Generating call tree... (sorting on %s)"
             byte-compile-call-tree-sort)
    (insert "Call tree for "
            (cond ((null byte-compile-current-file) (or filename "???"))
                  ((stringp byte-compile-current-file)
                   byte-compile-current-file)
                  (t (buffer-name byte-compile-current-file)))
            " sorted on "
            (prin1-to-string byte-compile-call-tree-sort)
            ":\n\n")
    (if byte-compile-call-tree-sort
        (setq byte-compile-call-tree
              (sort byte-compile-call-tree
                    (pcase byte-compile-call-tree-sort
                      (`callers
                       (lambda (x y) (< (length (nth 1 x))
                                   (length (nth 1 y)))))
                      (`calls
                       (lambda (x y) (< (length (nth 2 x))
                                   (length (nth 2 y)))))
                      (`calls+callers
                       (lambda (x y) (< (+ (length (nth 1 x))
                                      (length (nth 2 x)))
                                   (+ (length (nth 1 y))
                                      (length (nth 2 y))))))
                      (`name
                       (lambda (x y) (string< (car x) (car y))))
                      (_ (error "`byte-compile-call-tree-sort': `%s' - unknown sort mode"
                                byte-compile-call-tree-sort))))))
    (message "Generating call tree...")
    (let ((rest byte-compile-call-tree)
          (b (current-buffer))
          f p
          callers calls)
      (while rest
        (prin1 (car (car rest)) b)
        (setq callers (nth 1 (car rest))
              calls (nth 2 (car rest)))
        (insert "\t"
          (cond ((not (fboundp (setq f (car (car rest)))))
                 (if (null f)
                     " <top level>";; shouldn't insert nil then, actually -sk
                   " <not defined>"))
                ((subrp (setq f (symbol-function f)))
                 " <subr>")
                ((symbolp f)
                 (format " ==> %s" f))
                ((byte-code-function-p f)
                 "<compiled function>")
                ((not (consp f))
                 "<malformed function>")
                ((eq 'macro (car f))
                 (if (or (byte-code-function-p (cdr f))
                         (assq 'byte-code (cdr (cdr (cdr f)))))
                     " <compiled macro>"
                   " <macro>"))
                ((assq 'byte-code (cdr (cdr f)))
                 "<compiled lambda>")
                ((eq 'lambda (car f))
                 "<function>")
                (t "???"))
          (format " (%d callers + %d calls = %d)"
                  ;; Does the optimizer eliminate common subexpressions?-sk
                  (length callers)
                  (length calls)
                  (+ (length callers) (length calls)))
          "\n")
        (if callers
            (progn
              (insert "  called by:\n")
              (setq p (point))
              (insert "    " (if (car callers)
                                 (mapconcat 'symbol-name callers ", ")
                               "<top level>"))
              (let ((fill-prefix "    "))
                (fill-region-as-paragraph p (point)))
              (unless (= 0 (current-column))
                (insert "\n"))))
        (if calls
            (progn
              (insert "  calls:\n")
              (setq p (point))
              (insert "    " (mapconcat 'symbol-name calls ", "))
              (let ((fill-prefix "    "))
                (fill-region-as-paragraph p (point)))
              (unless (= 0 (current-column))
                (insert "\n"))))
        (setq rest (cdr rest)))

      (message "Generating call tree...(finding uncalled functions...)")
      (setq rest byte-compile-call-tree)
      (let (uncalled def)
        (while rest
          (or (nth 1 (car rest))
              (null (setq f (caar rest)))
              (progn
                (setq def (byte-compile-fdefinition f t))
                (and (eq (car-safe def) 'macro)
                     (eq (car-safe (cdr-safe def)) 'lambda)
                     (setq def (cdr def)))
                (functionp def))
              (progn
                (setq def (byte-compile-fdefinition f nil))
                (and (eq (car-safe def) 'macro)
                     (eq (car-safe (cdr-safe def)) 'lambda)
                     (setq def (cdr def)))
                (commandp def))
              (setq uncalled (cons f uncalled)))
          (setq rest (cdr rest)))
        (if uncalled
            (let ((fill-prefix "  "))
              (insert "Noninteractive functions not known to be called:\n  ")
              (setq p (point))
              (insert (mapconcat 'symbol-name (nreverse uncalled) ", "))
              (fill-region-as-paragraph p (point))))))
    (message "Generating call tree...done.")))

\f
;;;###autoload
(defun batch-byte-compile-if-not-done ()
  "Like `byte-compile-file' but doesn't recompile if already up to date.
Use this from the command line, with `-batch';
it won't work in an interactive Emacs."
  (batch-byte-compile t))

;;; by crl@newton.purdue.edu
;;;  Only works noninteractively.
;;;###autoload
(defun batch-byte-compile (&optional noforce)
  "Run `byte-compile-file' on the files remaining on the command line.
Use this from the command line, with `-batch';
it won't work in an interactive Emacs.
Each file is processed even if an error occurred previously.
For example, invoke \"emacs -batch -f batch-byte-compile $emacs/ ~/*.el\".
If NOFORCE is non-nil, don't recompile a file that seems to be
already up-to-date."
  ;; command-line-args-left is what is left of the command line, from
  ;; startup.el.
  (defvar command-line-args-left)       ;Avoid 'free variable' warning
  (if (not noninteractive)
      (error "`batch-byte-compile' is to be used only with -batch"))
  (let ((error nil))
    (while command-line-args-left
      (if (file-directory-p (expand-file-name (car command-line-args-left)))
          ;; Directory as argument.
          (let (source dest)
            (dolist (file (directory-files (car command-line-args-left)))
              (if (and (string-match emacs-lisp-file-regexp file)
                       (not (auto-save-file-name-p file))
                       (setq source
                             (expand-file-name file
                                               (car command-line-args-left)))
                       (setq dest (byte-compile-dest-file source))
                       (file-exists-p dest)
                       (file-newer-than-file-p source dest))
                  (if (null (batch-byte-compile-file source))
                      (setq error t)))))
        ;; Specific file argument
        (if (or (not noforce)
                (let* ((source (car command-line-args-left))
                       (dest (byte-compile-dest-file source)))
                  (or (not (file-exists-p dest))
                      (file-newer-than-file-p source dest))))
            (if (null (batch-byte-compile-file (car command-line-args-left)))
                (setq error t))))
      (setq command-line-args-left (cdr command-line-args-left)))
    (kill-emacs (if error 1 0))))

(defun batch-byte-compile-file (file)
  (let ((byte-compile-root-dir (or byte-compile-root-dir default-directory)))
    (if debug-on-error
        (byte-compile-file file)
      (condition-case err
          (byte-compile-file file)
        (file-error
         (message (if (cdr err)
                      ">>Error occurred processing %s: %s (%s)"
                    ">>Error occurred processing %s: %s")
                  file
                  (get (car err) 'error-message)
                  (prin1-to-string (cdr err)))
         (let ((destfile (byte-compile-dest-file file)))
           (if (file-exists-p destfile)
               (delete-file destfile)))
         nil)
        (error
         (message (if (cdr err)
                      ">>Error occurred processing %s: %s (%s)"
                    ">>Error occurred processing %s: %s")
                  file
                  (get (car err) 'error-message)
                  (prin1-to-string (cdr err)))
         nil)))))

(defun byte-compile-refresh-preloaded ()
  "Reload any Lisp file that was changed since Emacs was dumped.
Use with caution."
  (let* ((argv0 (car command-line-args))
         (emacs-file (executable-find argv0)))
    (if (not (and emacs-file (file-executable-p emacs-file)))
        (message "Can't find %s to refresh preloaded Lisp files" argv0)
      (dolist (f (reverse load-history))
        (setq f (car f))
        (if (string-match "elc\\'" f) (setq f (substring f 0 -1)))
        (when (and (file-readable-p f)
                   (file-newer-than-file-p f emacs-file)
                   ;; Don't reload the source version of the files below
                   ;; because that causes subsequent byte-compilation to
                   ;; be a lot slower and need a higher max-lisp-eval-depth,
                   ;; so it can cause recompilation to fail.
                   (not (member (file-name-nondirectory f)
                                '("pcase.el" "bytecomp.el" "macroexp.el"
                                  "cconv.el" "byte-opt.el"))))
          (message "Reloading stale %s" (file-name-nondirectory f))
          (condition-case nil
              (load f 'noerror nil 'nosuffix)
            ;; Probably shouldn't happen, but in case of an error, it seems
            ;; at least as useful to ignore it as it is to stop compilation.
            (error nil)))))))

;;;###autoload
(defun batch-byte-recompile-directory (&optional arg)
  "Run `byte-recompile-directory' on the dirs remaining on the command line.
Must be used only with `-batch', and kills Emacs on completion.
For example, invoke `emacs -batch -f batch-byte-recompile-directory .'.

Optional argument ARG is passed as second argument ARG to
`byte-recompile-directory'; see there for its possible values
and corresponding effects."
  ;; command-line-args-left is what is left of the command line (startup.el)
  (defvar command-line-args-left)       ;Avoid 'free variable' warning
  (if (not noninteractive)
      (error "batch-byte-recompile-directory is to be used only with -batch"))
  (or command-line-args-left
      (setq command-line-args-left '(".")))
  (while command-line-args-left
    (byte-recompile-directory (car command-line-args-left) arg)
    (setq command-line-args-left (cdr command-line-args-left)))
  (kill-emacs 0))

;;; Core compiler macros.

(put 'featurep 'compiler-macro
     (lambda (form feature &rest _ignore)
       ;; Emacs-21's byte-code doesn't run under XEmacs or SXEmacs anyway, so
       ;; we can safely optimize away this test.
       (if (member feature '('xemacs 'sxemacs 'emacs))
           (eval form)
         form)))

(provide 'byte-compile)
(provide 'bytecomp)

\f
;;; report metering (see the hacks in bytecode.c)

(defvar byte-code-meter)
(defun byte-compile-report-ops ()
  (or (boundp 'byte-metering-on)
      (error "You must build Emacs with -DBYTE_CODE_METER to use this"))
  (with-output-to-temp-buffer "*Meter*"
    (set-buffer "*Meter*")
    (let ((i 0) n op off)
      (while (< i 256)
        (setq n (aref (aref byte-code-meter 0) i)
              off nil)
        (if t                           ;(not (zerop n))
            (progn
              (setq op i)
              (setq off nil)
              (cond ((< op byte-nth)
                     (setq off (logand op 7))
                     (setq op (logand op 248)))
                    ((>= op byte-constant)
                     (setq off (- op byte-constant)
                           op byte-constant)))
              (setq op (aref byte-code-vector op))
              (insert (format "%-4d" i))
              (insert (symbol-name op))
              (if off (insert " [" (int-to-string off) "]"))
              (indent-to 40)
              (insert (int-to-string n) "\n")))
        (setq i (1+ i))))))
\f
;; To avoid "lisp nesting exceeds max-lisp-eval-depth" when bytecomp compiles
;; itself, compile some of its most used recursive functions (at load time).
;;
(eval-when-compile
  (or (byte-code-function-p (symbol-function 'byte-compile-form))
      (assq 'byte-code (symbol-function 'byte-compile-form))
      (let ((byte-optimize nil)         ; do it fast
            (byte-compile-warnings nil))
        (mapc (lambda (x)
                (or noninteractive (message "compiling %s..." x))
                (byte-compile x)
                (or noninteractive (message "compiling %s...done" x)))
              '(byte-compile-normal-call
                byte-compile-form
                byte-compile-body
                ;; Inserted some more than necessary, to speed it up.
                byte-compile-top-level
                byte-compile-out-toplevel
                byte-compile-constant
                byte-compile-variable-ref))))
  nil)

(run-hooks 'bytecomp-load-hook)

;;; bytecomp.el ends here