X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Feval.lisp;h=f8ef5b0bccab8ff03939912a23e9156f7c977eeb;hb=a260738d7a71680079d972b102b4e4db4e8dc3ae;hp=cd5b0df6cb261c01fa2f5d43f919928073513015;hpb=197ca115fd3265b4525213ece17800215fbd1203;p=sbcl.git diff --git a/src/code/eval.lisp b/src/code/eval.lisp index cd5b0df..f8ef5b0 100644 --- a/src/code/eval.lisp +++ b/src/code/eval.lisp @@ -1,3 +1,5 @@ +;;;; EVAL and friends + ;;;; This software is part of the SBCL system. See the README file for ;;;; more information. ;;;; @@ -7,89 +9,50 @@ ;;;; 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))) - -;;; 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 - -;;; 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) - ;;; 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)))) +;;; EVAL-WHEN magic properly): Delegate to #'COMPILE. +(defun %eval (expr lexenv) + (funcall (sb!c:compile-in-lexenv + (gensym "EVAL-TMPFUN-") + `(lambda () + ,expr) + lexenv))) + +;;; Handle PROGN and implicit PROGN. +(defun eval-progn-body (progn-body lexenv) + (unless (list-with-length-p progn-body) + (let ((*print-circle* t)) + (error 'simple-program-error + :format-control + "~@" + :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 + (eval-in-lexenv (first i) lexenv) + (return (eval-in-lexenv (first i) lexenv))))) -;;; 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. (defun eval (original-exp) #!+sb-doc "Evaluate the argument in a null lexical environment, returning the result or results." + (eval-in-lexenv original-exp (make-null-lexenv))) + +;;; Pick off a few easy cases, and the various top level EVAL-WHEN +;;; magical cases, and call %EVAL for the rest. +(defun eval-in-lexenv (original-exp lexenv) (declare (optimize (safety 1))) - (let ((exp (macroexpand original-exp))) + ;; (aver (lexenv-simple-p lexenv)) + (let ((exp (macroexpand original-exp lexenv))) (typecase exp (symbol (ecase (info :variable :kind exp) @@ -97,29 +60,40 @@ (values (info :variable :constant-value exp))) ((:special :global) (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 - (sb!bytecode:internal-eval original-exp)))) + (%eval original-exp lexenv)))) (list (let ((name (first exp)) - (args (1- (length exp)))) + (n-args (1- (length exp)))) (case name - (function - (unless (= args 1) + ((function) + (unless (= n-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))) + (if (and (or (atom name) + (and (consp name) + (eq (car name) 'setf))) + (not (consp (let ((sb!c:*lexenv* lexenv)) + (sb!c:lexenv-find name funs))))) (fdefinition name) - (sb!bytecode:internal-eval original-exp)))) - (quote - (unless (= args 1) + (%eval original-exp lexenv)))) + ((quote) + (unless (= n-args 1) (error "wrong number of args to QUOTE:~% ~S" exp)) (second exp)) (setq - (unless (evenp args) + (unless (evenp n-args) (error "odd number of args to SETQ:~% ~S" exp)) - (unless (zerop args) + (unless (zerop n-args) (do ((name (cdr exp) (cddr name))) ((null name) (do ((args (cdr exp) (cddr args))) @@ -130,75 +104,109 @@ (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* + ;; FIXME: I took out the *TOPLEVEL-AUTO-DECLARE* + ;; test here, and removed the *TOPLEVEL-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)))))))) + (t (return (%eval original-exp lexenv)))))))) ((progn) - (when (> args 0) - (dolist (x (butlast (rest exp)) (eval (car (last exp)))) - (eval x)))) + (eval-progn-body (rest exp) lexenv)) ((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))) + ;; 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 + (eval-progn-body body lexenv))))) + ((locally) + (multiple-value-bind (body decls) (parse-body (rest exp) 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)) + (sb!c::process-decls decls + nil nil + (sb!c::make-continuation) + lexenv)))) + (eval-progn-body body lexenv)))) + ((macrolet) + (destructuring-bind (definitions &rest body) + (rest exp) + ;; FIXME: shared code with FUNCALL-IN-FOOMACROLET-LEXENV + (declare (type list definitions)) + (unless (= (length definitions) + (length (remove-duplicates definitions :key #'first))) + (style-warn "duplicate definitions in ~S" definitions)) + (let ((lexenv + (sb!c::make-lexenv + :default lexenv + :funs (mapcar + (sb!c::macrolet-definitionize-fun + :eval + ;; I'm not sure that this is the correct + ;; LEXENV to be compiling local macros + ;; in... + lexenv) + definitions)))) + (eval-in-lexenv `(locally ,@body) lexenv)))) + ((symbol-macrolet) + (destructuring-bind (definitions &rest body) + (rest exp) + ;; FIXME: shared code with FUNCALL-IN-FOOMACROLET-LEXENV + (declare (type list definitions)) + (unless (= (length definitions) + (length (remove-duplicates definitions :key #'first))) + (style-warn "duplicate definitions in ~S" definitions)) + (let ((lexenv + (sb!c::make-lexenv + :default lexenv + :vars (mapcar + (sb!c::symbol-macrolet-definitionize-fun + :eval) + definitions)))) + (eval-in-lexenv `(locally ,@body) lexenv)))) (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)))))) + (dolist (arg (rest exp)) + (args (eval-in-lexenv arg lexenv))) + (apply (symbol-function name) (args))) + (%eval exp lexenv)))))) (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))))) ;;; miscellaneous full function definitions of things which are ;;; ordinarily handled magically by the compiler