ecl/src/cmp/cmpmulti.lsp
2004-11-23 15:07:17 +00:00

323 lines
11 KiB
Common Lisp

;;;; Copyright (c) 1984, Taiichi Yuasa and Masami Hagiya.
;;;; Copyright (c) 1990, Giuseppe Attardi.
;;;;
;;;; This program is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Library General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 2 of the License, or (at your option) any later version.
;;;;
;;;; See file '../Copyright' for full details.
;;;; CMPMULT Multiple-value-call and Multiple-value-prog1.
(in-package "COMPILER")
(defun c1multiple-value-call (args &aux forms)
(check-args-number 'MULTIPLE-VALUE-CALL args 1)
(cond
;; (M-V-C #'FUNCTION) => (FUNCALL #'FUNCTION)
((endp (rest args)) (c1funcall args))
;; (M-V-C #'FUNCTION (VALUES A ... Z)) => (FUNCALL #'FUNCTION A ... Z)
((and (= (length args) 2)
(consp (setq forms (second args)))
(eq 'VALUES (first forms)))
(c1funcall (list* (first args) (rest forms))))
;; More complicated case.
(t (let ((funob (c1expr (first args))))
(make-c1form 'MULTIPLE-VALUE-CALL funob funob (c1args* (rest args)))))))
(defun c2multiple-value-call (funob forms)
(let* ((tot (make-lcl-var :rep-type :cl-index))
(*temp* *temp*)
(loc (maybe-save-value funob forms)))
(wt-nl "{ cl_index " tot "=0;")
(let ((*unwind-exit* `((STACK ,tot) ,@*unwind-exit*)))
(let ((*destination* 'VALUES))
(dolist (form forms)
(c2expr* form)
(wt-nl tot "+=cl_stack_push_values();")))
(c2funcall funob 'ARGS-PUSHED loc tot))
(wt "}"))
)
(defun c1multiple-value-prog1 (args)
(check-args-number 'MULTIPLE-VALUE-PROG1 args 1)
(make-c1form* 'MULTIPLE-VALUE-PROG1 :args (c1expr (first args))
(c1args* (rest args))))
(defun c2multiple-value-prog1 (form forms)
(if (eq 'TRASH *destination*)
;; dont bother saving values
(c2progn (cons form forms))
(let ((nr (make-lcl-var :type :cl-index)))
(let ((*destination* 'VALUES)) (c2expr* form))
(wt-nl "{ cl_index " nr "=cl_stack_push_values();")
(let ((*destination* 'TRASH)
(*unwind-exit* `((STACK ,nr) ,@*unwind-exit*)))
(dolist (form forms)
(c2expr* form)))
(wt-nl "cl_stack_pop_values(" nr ");}")
(unwind-exit 'VALUES))))
;;; Beppe:
;;; this is the WRONG way to handle 1 value problem.
;;; should be done in c2values, so that (values (truncate a b)) can
;;; be used to restrict to one value, so we would not have to warn
;;; if this occurred in a proclaimed fun.
(defun c1values (args)
(make-c1form* 'VALUES :args (c1args* args)))
(defun c2values (forms)
(when (and (eq *destination* 'RETURN-OBJECT)
(rest forms)
(consp *current-form*)
(eq 'DEFUN (first *current-form*)))
(cmpwarn "Trying to return multiple values. ~
~%;But ~a was proclaimed to have single value.~
~%;Only first one will be assured."
(second *current-form*)))
(cond
;; When the values are not going to be used, then just
;; process each form separately.
((eq *destination* 'TRASH)
(mapc #'c2expr* forms))
;; For (VALUES) we can replace the output with either NIL (if the value
;; is actually used) and set only NVALUES when the value is the output
;; of a function.
((endp forms)
(cond ((eq *destination* 'RETURN)
(wt-nl "value0=Cnil; NVALUES=0;")
(unwind-exit 'RETURN))
((eq *destination* 'VALUES)
(wt-nl "VALUES(0)=Cnil; NVALUES=0;")
(unwind-exit 'VALUES))
(t
(unwind-exit 'NIL))))
;; For a single form, we must simply ensure that we only take a single
;; value of those that the function may output.
((endp (rest forms))
(let ((*destination* 'VALUE0))
(c2expr* (first forms)))
(unwind-exit 'VALUE0))
;; In all other cases, we store the values in the VALUES vector,
;; and force the compiler to retrieve anything out of it.
(t
(let* ((nv (length forms))
(*inline-blocks* 0)
(forms (nreverse (coerce-locs (inline-args forms)))))
;; By inlining arguments we make sure that VL has no call to funct.
;; Reverse args to avoid clobbering VALUES(0)
(wt-nl "NVALUES=" nv ";")
(do ((vl forms (rest vl))
(i (1- (length forms)) (1- i)))
((null vl))
(declare (fixnum i))
(wt-nl "VALUES(" i ")=" (first vl) ";"))
(unwind-exit 'VALUES)
(close-inline-blocks)))))
(defun c1multiple-value-setq (args &aux (vars nil) (temp-vars nil)
(late-bindings nil))
(check-args-number 'MULTIPLE-VALUE-SETQ args 2 2)
(dolist (var (reverse (first args)))
(cmpck (not (symbolp var)) "The variable ~s is not a symbol." var)
(setq var (chk-symbol-macrolet var))
(cond ((symbolp var)
(cmpck (constantp var)
"The constant ~s is being assigned a value." var)
(push var vars))
(t (let ((new-var (gensym)))
(push new-var vars)
(push new-var temp-vars)
(push `(setf ,var ,new-var) late-bindings)))))
(let ((value (second args)))
(cond (temp-vars
(c1expr `(let* (,@temp-vars)
(multiple-value-setq ,vars ,value)
,@late-bindings)))
((endp vars)
(c1expr `(values ,value)))
((= (length vars) 1)
(c1expr `(setq ,(first vars) ,value)))
(t
(setq value (c1expr value)
vars (mapcar #'c1vref vars))
(make-c1form* 'MULTIPLE-VALUE-SETQ
:changed-vars vars
:referred-vars vars
:local-referred vars
:args vars value)))))
(defun c1form-values-number (form)
(let ((type (c1form-type form)))
(cond ((eq type 'T)
(values 0 MULTIPLE-VALUES-LIMIT))
((or (atom type) (not (eq (first type) 'VALUES)))
(values 1 1))
((or (member '&rest type) (member 'optional type))
(values 0 MULTIPLE-VALUES-LIMIT))
(t
(let ((l (1- (length type))))
(values l l))))))
(defun do-m-v-setq-fixed (nvalues vars form use-bind &aux (output (first vars)))
;; This routine should evaluate FORM and store the values (whose amount
;; is known to be NVALUES) into the variables VARS. The output is a
;; place from where the first value can be retreived
;;
(if (or (> nvalues 1) use-bind)
(let ((*destination* 'VALUES))
(c2expr* form)
(dotimes (i nvalues)
(funcall (if use-bind #'bind-var #'set-var)
(values-loc i) (pop vars))))
(let ((*destination* (pop vars)))
(c2expr* form)))
(dolist (v vars)
(if use-bind
(bind (c1form-arg 0 (default-init v)) v)
(set-var '(C-INLINE :object "Cnil" () t nil) v)))
output)
(defun do-m-v-setq-any (min-values max-values vars use-bind)
;; This routine moves values from the multiple-value stack into the
;; variables VARS. The amount of values is not known (or at least we only
;; know that there is some number between MIN-VALUES and MAX-VALUES). If
;; the values are to be created with BIND, then USED-BIND=T. The output of
;; this routine is a location containing the first value (typically, the
;; name of the first variable).
;;
(let* ((*lcl* *lcl*)
(nr (make-lcl-var :type :int))
(output (first vars))
(labels '()))
;; We know that at least MIN-VALUES variables will get a value
(dotimes (i min-values)
(when vars
(let ((v (pop vars))
(loc (values-loc i)))
(if use-bind (bind loc v) (set-var loc v)))))
;; If there are more variables, we have to check whether there
;; are enough values left in the stack.
(when vars
(wt-nl "{int " nr "=NVALUES-" min-values ";")
;;
;; Loop for assigning values to variables
;;
(do ((vs vars (rest vs))
(i min-values (1+ i)))
((or (endp vs) (= i max-values)))
(declare (fixnum i))
(let ((loc (values-loc i))
(v (first vs))
(label (next-label)))
(wt-nl "if (" nr "--<=0) ") (wt-go label)
(push label labels)
(if use-bind (bind loc v) (set-var loc v))))
;;
;; Loop for setting default values when there are less output than vars.
;;
(let ((label (next-label)))
(wt-nl) (wt-go label) (wt "}")
(push label labels)
(setq labels (nreverse labels))
(dolist (v vars)
(when labels (wt-label (pop labels)))
(if use-bind
(bind '(C-INLINE :object "Cnil" () t nil) v)
(set-var '(C-INLINE :object "Cnil" () t nil) v)))
(when labels (wt-label label))))
output))
(defun c2multiple-value-setq (vars form)
(multiple-value-bind (min-values max-values)
(c1form-values-number form)
(unwind-exit
(if (= min-values max-values)
(do-m-v-setq-fixed min-values vars form nil)
(let ((*destination* 'VALUES))
(c2expr* form)
(do-m-v-setq-any min-values max-values vars nil))))))
(defun c1multiple-value-bind (args &aux (vars nil) (vnames nil) init-form
ss is ts body other-decls
(*vars* *vars*))
(check-args-number 'MULTIPLE-VALUE-BIND args 2)
(multiple-value-setq (body ss ts is other-decls) (c1body (cddr args) nil))
(c1add-globals ss)
(dolist (s (first args))
(push s vnames)
(push (c1make-var s ss is ts) vars))
(setq init-form (c1expr (second args)))
(dolist (v (setq vars (nreverse vars)))
(push-vars v))
(check-vdecl vnames ts is)
(setq body (c1decl-body other-decls body))
(dolist (var vars) (check-vref var))
(make-c1form* 'MULTIPLE-VALUE-BIND :type (c1form-type body)
:local-vars vars
:args vars init-form body)
)
(defun c2multiple-value-bind (vars init-form body)
;; 0) Compile the form which is going to give us the values
(let ((*destination* 'VALUES)) (c2expr* init-form))
(let* ((*unwind-exit* *unwind-exit*)
(*env-lvl* *env-lvl*)
(*env* *env*)
(*lcl* *lcl*)
(labels nil)
(env-grows nil)
(nr (make-lcl-var :type :int))
min-values max-values)
;; 1) Retrieve the number of output values
(wt-nl "{")
(multiple-value-setq (min-values max-values)
(c1form-values-number init-form))
;; 2) For all variables which are not special and do not belong to
;; a closure, make a local C variable.
(dolist (var vars)
(declare (type var var))
(let ((kind (local var)))
(if kind
(progn
(bind (next-lcl) var)
(wt-nl *volatile* (rep-type-name kind) " " var ";")
(wt-comment (var-name var)))
(unless env-grows (setq env-grows (var-ref-ccb var))))))
;; 3) If there are closure variables, set up an environment.
(when (setq env-grows (env-grows env-grows))
(let ((env-lvl *env-lvl*))
(wt-nl "volatile cl_object env" (incf *env-lvl*)
" = env" env-lvl ";")))
;; 4) Assign the values to the variables
(do-m-v-setq-any min-values max-values vars t)
;; 5) Compile the body. If there are bindings of special variables,
;; these bindings are undone here.
(c2expr body)
;; 6) Close the C expression.
(wt "}"))
)
;;; ----------------------------------------------------------------------
(put-sysprop 'multiple-value-call 'c1special 'c1multiple-value-call)
(put-sysprop 'multiple-value-call 'c2 'c2multiple-value-call)
(put-sysprop 'multiple-value-prog1 'c1special 'c1multiple-value-prog1)
(put-sysprop 'multiple-value-prog1 'c2 'c2multiple-value-prog1)
(put-sysprop 'values 'c1 'c1values)
(put-sysprop 'values 'c2 'c2values)
(put-sysprop 'multiple-value-setq 'c1 'c1multiple-value-setq)
(put-sysprop 'multiple-value-setq 'c2 'c2multiple-value-setq)
(put-sysprop 'multiple-value-bind 'c1 'c1multiple-value-bind)
(put-sysprop 'multiple-value-bind 'c2 'c2multiple-value-bind)