+;;;; EVAL and friends
+
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;;;;
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.
-(in-package "SB!BYTECODE")
-
-;;; This is defined here so that the printer etc. can call
-;;; INTERPRETED-FUNCTION-P before the full interpreter is loaded.
-
-;;; an interpreted function
-(defstruct (interpreted-function
- (:alternate-metaclass sb!kernel:funcallable-instance
- sb!kernel:funcallable-structure-class
- sb!kernel:make-funcallable-structure-class)
- (:type sb!kernel:funcallable-structure)
- (:constructor %make-interpreted-function)
- (:copier nil)
- ;; FIXME: Binding PRINT-OBJECT isn't going to help unless
- ;; we fix the print-a-funcallable-instance code so that
- ;; it calls PRINT-OBJECT in this case.
- (:print-object
- (lambda (x stream)
- (print-unreadable-object (x stream :identity t)
- (interpreted-function-%name x)))))
- ;; The name of this interpreted function, or NIL if none specified.
- (%name nil)
- ;; This function's debug arglist.
- (arglist nil)
- ;; A lambda that can be converted to get the definition.
- (lambda nil)
- ;; If this function has been converted, then this is the XEP. If this is
- ;; false, then the function is not in the cache (or is in the process of
- ;; being removed.)
- (definition nil :type (or sb!c::clambda null))
- ;; The number of consecutive GCs that this function has been unused.
- ;; This is used to control cache replacement.
- (gcs 0 :type sb!c::index)
- ;; True if Lambda has been converted at least once, and thus warnings should
- ;; be suppressed on additional conversions.
- (converted-once nil)
- ;; For a closure, the closure date vector.
- (closure nil :type (or null simple-vector)))
-\f
-;;; FIXME: Could we make this extra IN-PACKAGE go away, so that all
-;;; this bytecode interpreter implementation stuff was in the
-;;; SB!BYTECODE package?
(in-package "SB!IMPL")
-;;;; EVAL and friends
+(defparameter *eval-calls* 0)
-;;; This needs to be initialized in the cold load, since the top-level
-;;; catcher will always restore the initial value.
-(defvar *eval-stack-top* 0)
+(defun !eval-cold-init ()
+ (setf *eval-calls* 0
+ *evaluator-mode* :compile)
+ #!+sb-eval
+ (setf sb!eval::*eval-level* -1
+ sb!eval::*eval-verbose* nil))
;;; general case of EVAL (except in that it can't handle toplevel
-;;; EVAL-WHEN magic properly): Delegate to the byte compiler.
-(defun sb!bytecode:internal-eval (expr)
- (funcall (compile (gensym "EVAL-TMPFUN-")
- `(lambda ()
-
- ;; SPEED=0,DEBUG=1 => byte-compile
- (declare (optimize (speed 0) (debug 1)))
-
- ;; Other than that, basically we care about
- ;; compilation speed, compilation speed, and
- ;; compilation speed. (There are cases where
- ;; the user wants something else, but we don't
- ;; know enough to guess that; and if he is
- ;; unhappy about our guessed emphasis, he
- ;; should explicitly compile his code, with
- ;; explicit declarations to tell us what to
- ;; emphasize.)
- (declare (optimize (space 1) (safety 1)))
- (declare (optimize (compilation-speed 3)))
-
- ,expr))))
-
-;;; Pick off a few easy cases, and call INTERNAL-EVAL for the rest. If
-;;; *ALREADY-EVALED-THIS* is true, then we bind it to NIL before doing
-;;; a call so that the effect is confined to the lexical scope of the
-;;; EVAL-WHEN.
+;;; EVAL-WHEN magic properly): Delegate to #'COMPILE.
+(defun %simple-eval (expr lexenv)
+ ;; FIXME: It might be nice to quieten the toplevel by muffling
+ ;; warnings generated by this compilation (since we're about to
+ ;; execute the results irrespective of the warnings). We might want
+ ;; to be careful about not muffling warnings arising from inner
+ ;; evaluations/compilations, though [e.g. the ignored variable in
+ ;; (DEFUN FOO (X) 1)]. -- CSR, 2003-05-13
+ ;;
+ ;; As of 1.0.21.6 we muffle compiler notes lexically here, which seems
+ ;; always safe. --NS
+ (let* (;; why PROGN? So that attempts to eval free declarations
+ ;; signal errors rather than return NIL. -- CSR, 2007-05-01
+ (lambda `(lambda ()
+ (declare (muffle-conditions compiler-note))
+ (progn ,expr)))
+ (fun (sb!c:compile-in-lexenv nil lambda lexenv)))
+ (funcall fun)))
+
+;;; Handle PROGN and implicit PROGN.
+(defun simple-eval-progn-body (progn-body lexenv)
+ (unless (list-with-length-p progn-body)
+ (let ((*print-circle* t))
+ (error 'simple-program-error
+ :format-control
+ "~@<not a proper list in PROGN or implicit PROGN: ~2I~_~S~:>"
+ :format-arguments (list progn-body))))
+ ;; Note:
+ ;; * We can't just use (MAP NIL #'EVAL PROGN-BODY) here, because we
+ ;; need to take care to return all the values of the final EVAL.
+ ;; * It's left as an exercise to the reader to verify that this
+ ;; gives the right result when PROGN-BODY is NIL, because
+ ;; (FIRST NIL) = (REST NIL) = NIL.
+ (do* ((i progn-body rest-i)
+ (rest-i (rest i) (rest i)))
+ (nil)
+ (if rest-i ; if not last element of list
+ (simple-eval-in-lexenv (first i) lexenv)
+ (return (simple-eval-in-lexenv (first i) lexenv)))))
+
+(defun simple-eval-locally (exp lexenv &key vars)
+ (multiple-value-bind (body decls)
+ (parse-body (rest exp) :doc-string-allowed nil)
+ (let ((lexenv
+ ;; KLUDGE: Uh, yeah. I'm not anticipating
+ ;; winning any prizes for this code, which was
+ ;; written on a "let's get it to work" basis.
+ ;; These seem to be the variables that need
+ ;; bindings for PROCESS-DECLS to work
+ ;; (*FREE-FUNS* and *FREE-VARS* so that
+ ;; references to free functions and variables
+ ;; in the declarations can be noted;
+ ;; *UNDEFINED-WARNINGS* so that warnings about
+ ;; undefined things can be accumulated [and
+ ;; then thrown away, as it happens]). -- CSR,
+ ;; 2002-10-24
+ (let* ((sb!c:*lexenv* lexenv)
+ (sb!c::*free-funs* (make-hash-table :test 'equal))
+ (sb!c::*free-vars* (make-hash-table :test 'eq))
+ (sb!c::*undefined-warnings* nil))
+ ;; FIXME: VALUES declaration
+ (sb!c::process-decls decls
+ vars
+ nil
+ :lexenv lexenv
+ :context :eval))))
+ (simple-eval-progn-body body lexenv))))
+
+;;;; EVAL-ERROR
+;;;;
+;;;; Analogous to COMPILER-ERROR, but simpler.
+
+(define-condition eval-error (encapsulated-condition)
+ ()
+ (:report (lambda (condition stream)
+ (print-object (encapsulated-condition condition) stream))))
+
+(defun eval-error (condition)
+ (signal 'eval-error :condition condition)
+ (bug "Unhandled EVAL-ERROR"))
+
+;;; Pick off a few easy cases, and the various top level EVAL-WHEN
+;;; magical cases, and call %SIMPLE-EVAL for the rest.
+(defun simple-eval-in-lexenv (original-exp lexenv)
+ (declare (optimize (safety 1)))
+ ;; (aver (lexenv-simple-p lexenv))
+ (incf *eval-calls*)
+ (handler-bind
+ ((sb!c:compiler-error
+ (lambda (c)
+ (if (boundp 'sb!c::*compiler-error-bailout*)
+ ;; if we're in the compiler, delegate either to a higher
+ ;; authority or, if that's us, back down to the
+ ;; outermost compiler handler...
+ (progn
+ (signal c)
+ nil)
+ ;; ... if we're not in the compiler, better signal the
+ ;; error straight away.
+ (invoke-restart 'sb!c::signal-error)))))
+ (let ((exp (macroexpand original-exp lexenv)))
+ (handler-bind ((eval-error
+ (lambda (condition)
+ (error 'interpreted-program-error
+ :condition (encapsulated-condition condition)
+ :form exp))))
+ (typecase exp
+ (symbol
+ (ecase (info :variable :kind exp)
+ ((:special :global :constant :unknown)
+ (symbol-value exp))
+ ;; FIXME: This special case here is a symptom of non-ANSI
+ ;; weirdness in SBCL's ALIEN implementation, which could
+ ;; cause problems for e.g. code walkers. It'd probably be
+ ;; good to ANSIfy it by making alien variable accessors
+ ;; into ordinary forms, e.g. (SB-UNIX:ENV) and (SETF
+ ;; SB-UNIX:ENV), instead of magical symbols, e.g. plain
+ ;; SB-UNIX:ENV. Then if the old magical-symbol syntax is to
+ ;; be retained for compatibility, it can be implemented
+ ;; with DEFINE-SYMBOL-MACRO, keeping the code walkers
+ ;; happy.
+ (:alien
+ (%simple-eval original-exp lexenv))))
+ (list
+ (let ((name (first exp))
+ (n-args (1- (length exp))))
+ (case name
+ ((function)
+ (unless (= n-args 1)
+ (error "wrong number of args to FUNCTION:~% ~S" exp))
+ (let ((name (second exp)))
+ (if (and (legal-fun-name-p name)
+ (not (consp (let ((sb!c:*lexenv* lexenv))
+ (sb!c:lexenv-find name funs)))))
+ (%coerce-name-to-fun name)
+ (%simple-eval original-exp lexenv))))
+ ((quote)
+ (unless (= n-args 1)
+ (error "wrong number of args to QUOTE:~% ~S" exp))
+ (second exp))
+ (setq
+ (unless (evenp n-args)
+ (error "odd number of args to SETQ:~% ~S" exp))
+ (unless (zerop n-args)
+ (do ((name (cdr exp) (cddr name)))
+ ((null name)
+ (do ((args (cdr exp) (cddr args)))
+ ((null (cddr args))
+ ;; We duplicate the call to SET so that the
+ ;; correct value gets returned.
+ (set (first args)
+ (simple-eval-in-lexenv (second args) lexenv)))
+ (set (first args)
+ (simple-eval-in-lexenv (second args) lexenv))))
+ (let ((symbol (first name)))
+ (case (info :variable :kind symbol)
+ (:special)
+ (t (return (%simple-eval original-exp lexenv))))
+ (unless (type= (info :variable :type symbol)
+ *universal-type*)
+ ;; let the compiler deal with type checking
+ (return (%simple-eval original-exp lexenv)))))))
+ ((progn)
+ (simple-eval-progn-body (rest exp) lexenv))
+ ((eval-when)
+ ;; FIXME: DESTRUCTURING-BIND returns ARG-COUNT-ERROR
+ ;; instead of PROGRAM-ERROR when there's something wrong
+ ;; with the syntax here (e.g. missing SITUATIONS). This
+ ;; could be fixed by hand-crafting clauses to catch and
+ ;; report each possibility, but it would probably be
+ ;; cleaner to write a new macro
+ ;; DESTRUCTURING-BIND-PROGRAM-SYNTAX which does
+ ;; DESTRUCTURING-BIND and promotes any mismatch to
+ ;; PROGRAM-ERROR, then to use it here and in (probably
+ ;; dozens of) other places where the same problem
+ ;; arises.
+ (destructuring-bind (eval-when situations &rest body) exp
+ (declare (ignore eval-when))
+ (multiple-value-bind (ct lt e)
+ (sb!c:parse-eval-when-situations situations)
+ ;; CLHS 3.8 - Special Operator EVAL-WHEN: The use of
+ ;; the situation :EXECUTE (or EVAL) controls whether
+ ;; evaluation occurs for other EVAL-WHEN forms; that
+ ;; is, those that are not top level forms, or those
+ ;; in code processed by EVAL or COMPILE. If the
+ ;; :EXECUTE situation is specified in such a form,
+ ;; then the body forms are processed as an implicit
+ ;; PROGN; otherwise, the EVAL-WHEN form returns NIL.
+ (declare (ignore ct lt))
+ (when e
+ (simple-eval-progn-body body lexenv)))))
+ ((locally)
+ (simple-eval-locally exp lexenv))
+ ((macrolet)
+ (destructuring-bind (definitions &rest body)
+ (rest exp)
+ (let ((lexenv
+ (let ((sb!c:*lexenv* lexenv))
+ (sb!c::funcall-in-macrolet-lexenv
+ definitions
+ (lambda (&key funs)
+ (declare (ignore funs))
+ sb!c:*lexenv*)
+ :eval))))
+ (simple-eval-locally `(locally ,@body) lexenv))))
+ ((symbol-macrolet)
+ (destructuring-bind (definitions &rest body) (rest exp)
+ (multiple-value-bind (lexenv vars)
+ (let ((sb!c:*lexenv* lexenv))
+ (sb!c::funcall-in-symbol-macrolet-lexenv
+ definitions
+ (lambda (&key vars)
+ (values sb!c:*lexenv* vars))
+ :eval))
+ (simple-eval-locally `(locally ,@body) lexenv :vars vars))))
+ ((if)
+ (destructuring-bind (test then &optional else) (rest exp)
+ (eval-in-lexenv (if (eval-in-lexenv test lexenv)
+ then
+ else)
+ lexenv)))
+ ((let let*)
+ (destructuring-bind (definitions &rest body) (rest exp)
+ (if (null definitions)
+ (simple-eval-locally `(locally ,@body) lexenv)
+ (%simple-eval exp lexenv))))
+ (t
+ (if (and (symbolp name)
+ (eq (info :function :kind name) :function))
+ (collect ((args))
+ (dolist (arg (rest exp))
+ (args (eval-in-lexenv arg lexenv)))
+ (apply (symbol-function name) (args)))
+ (%simple-eval exp lexenv))))))
+ (t
+ exp))))))
+
+(defun eval-in-lexenv (exp lexenv)
+ #!+sb-eval
+ (if (eq *evaluator-mode* :compile)
+ (simple-eval-in-lexenv exp lexenv)
+ (sb!eval:eval-in-native-environment exp lexenv))
+ #!-sb-eval
+ (simple-eval-in-lexenv exp lexenv))
+
(defun eval (original-exp)
#!+sb-doc
"Evaluate the argument in a null lexical environment, returning the
- result or results."
- (declare (optimize (safety 1)))
- (let ((exp (macroexpand original-exp)))
- (typecase exp
- (symbol
- (ecase (info :variable :kind exp)
- (:constant
- (values (info :variable :constant-value exp)))
- ((:special :global)
- (symbol-value exp))
- (:alien
- (sb!bytecode:internal-eval original-exp))))
- (list
- (let ((name (first exp))
- (args (1- (length exp))))
- (case name
- (function
- (unless (= args 1)
- (error "wrong number of args to FUNCTION:~% ~S" exp))
- (let ((name (second exp)))
- (if (or (atom name)
- (and (consp name)
- (eq (car name) 'setf)))
- (fdefinition name)
- (sb!bytecode:internal-eval original-exp))))
- (quote
- (unless (= args 1)
- (error "wrong number of args to QUOTE:~% ~S" exp))
- (second exp))
- (setq
- (unless (evenp args)
- (error "odd number of args to SETQ:~% ~S" exp))
- (unless (zerop args)
- (do ((name (cdr exp) (cddr name)))
- ((null name)
- (do ((args (cdr exp) (cddr args)))
- ((null (cddr args))
- ;; We duplicate the call to SET so that the
- ;; correct value gets returned.
- (set (first args) (eval (second args))))
- (set (first args) (eval (second args)))))
- (let ((symbol (first name)))
- (case (info :variable :kind symbol)
- ;; FIXME: I took out the *TOP-LEVEL-AUTO-DECLARE*
- ;; test here, and removed the *TOP-LEVEL-AUTO-DECLARE*
- ;; variable; the code should now act as though that
- ;; variable is NIL. This should be tested..
- (:special)
- (t (return (sb!bytecode:internal-eval original-exp))))))))
- ((progn)
- (when (> args 0)
- (dolist (x (butlast (rest exp)) (eval (car (last exp))))
- (eval x))))
- ((eval-when)
- (if (and (> args 0)
- (or (member 'eval (second exp))
- (member :execute (second exp))))
- (when (> args 1)
- (dolist (x (butlast (cddr exp)) (eval (car (last exp))))
- (eval x)))
- (sb!bytecode:internal-eval original-exp)))
- (t
- (if (and (symbolp name)
- (eq (info :function :kind name) :function))
- (collect ((args))
- (dolist (arg (rest exp))
- (args (eval arg)))
- (apply (symbol-function name) (args)))
- (sb!bytecode:internal-eval original-exp))))))
- (t
- exp))))
-
-;;; Given a function, return three values:
-;;; 1] A lambda expression that could be used to define the function,
-;;; or NIL if the definition isn't available.
-;;; 2] NIL if the function was definitely defined in a null lexical
-;;; environment, and T otherwise.
-;;; 3] Some object that \"names\" the function. Although this is
-;;; allowed to be any object, CMU CL always returns a valid
-;;; function name or a string.
-;;;
-;;; If interpreted, use the interpreter interface. Otherwise, see
-;;; whether it was compiled with COMPILE. If that fails, check for an
-;;; inline expansion.
-(defun function-lambda-expression (fun)
- (declare (type function fun))
- (let* ((fun (%function-self fun))
- (name (%function-name fun))
- (code (sb!di::function-code-header fun))
- (info (sb!kernel:%code-debug-info code)))
- (if info
- (let ((source (first (sb!c::compiled-debug-info-source info))))
- (cond ((and (eq (sb!c::debug-source-from source) :lisp)
- (eq (sb!c::debug-source-info source) fun))
- (values (second (svref (sb!c::debug-source-name source) 0))
- nil name))
- ((stringp name)
- (values nil t name))
- (t
- (let ((exp (info :function :inline-expansion name)))
- (if exp
- (values exp nil name)
- (values nil t name))))))
- (values nil t name))))
-
-;;; This is like FIND-IF, except that we do it on a compiled closure's
-;;; environment.
-(defun find-if-in-closure (test fun)
- (dotimes (index (1- (get-closure-length fun)))
- (let ((elt (%closure-index-ref fun index)))
- (when (funcall test elt)
- (return elt)))))
+ result or results."
+ (eval-in-lexenv original-exp (make-null-lexenv)))
+
\f
;;; miscellaneous full function definitions of things which are
;;; ordinarily handled magically by the compiler
last argument, appended to the value of the last argument, which must be a
list."
(cond ((atom arguments)
- (apply function arg))
- ((atom (cdr arguments))
- (apply function (cons arg (car arguments))))
- (t (do* ((a1 arguments a2)
- (a2 (cdr arguments) (cdr a2)))
- ((atom (cdr a2))
- (rplacd a1 (car a2))
- (apply function (cons arg arguments)))))))
+ (apply function arg))
+ ((atom (cdr arguments))
+ (apply function (cons arg (car arguments))))
+ (t (do* ((a1 arguments a2)
+ (a2 (cdr arguments) (cdr a2)))
+ ((atom (cdr a2))
+ (rplacd a1 (car a2))
+ (apply function (cons arg arguments)))))))
(defun funcall (function &rest arguments)
#!+sb-doc
(defun values (&rest values)
#!+sb-doc
"Return all arguments, in order, as values."
+ (declare (truly-dynamic-extent values))
(values-list values))
(defun values-list (list)