1 ;;;; the usual place for DEF-IR1-TRANSLATOR forms (and their
2 ;;;; close personal friends)
4 ;;;; This software is part of the SBCL system. See the README file for
7 ;;;; This software is derived from the CMU CL system, which was
8 ;;;; written at Carnegie Mellon University and released into the
9 ;;;; public domain. The software is in the public domain and is
10 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
11 ;;;; files for more information.
15 ;;;; control special forms
17 (def-ir1-translator progn ((&rest forms) start cont)
20 Evaluates each Form in order, returning the values of the last form. With no
22 (ir1-convert-progn-body start cont forms))
24 (def-ir1-translator if ((test then &optional else) start cont)
26 "If Predicate Then [Else]
27 If Predicate evaluates to non-null, evaluate Then and returns its values,
28 otherwise evaluate Else and return its values. Else defaults to NIL."
29 (let* ((pred (make-continuation))
30 (then-cont (make-continuation))
31 (then-block (continuation-starts-block then-cont))
32 (else-cont (make-continuation))
33 (else-block (continuation-starts-block else-cont))
34 (dummy-cont (make-continuation))
35 (node (make-if :test pred
36 :consequent then-block
37 :alternative else-block)))
38 (setf (continuation-dest pred) node)
39 (ir1-convert start pred test)
40 (link-node-to-previous-continuation node pred)
41 (use-continuation node dummy-cont)
43 (let ((start-block (continuation-block pred)))
44 (setf (block-last start-block) node)
45 (continuation-starts-block cont)
47 (link-blocks start-block then-block)
48 (link-blocks start-block else-block))
50 (ir1-convert then-cont cont then)
51 (ir1-convert else-cont cont else)))
53 ;;;; BLOCK and TAGBODY
55 ;;;; We make an ENTRY node to mark the start and a :ENTRY cleanup to
56 ;;;; mark its extent. When doing GO or RETURN-FROM, we emit an EXIT
59 ;;; Make a :ENTRY cleanup and emit an ENTRY node, then convert the
60 ;;; body in the modified environment. We make CONT start a block now,
61 ;;; since if it was done later, the block would be in the wrong
63 (def-ir1-translator block ((name &rest forms) start cont)
66 Evaluate the Forms as a PROGN. Within the lexical scope of the body,
67 (RETURN-FROM Name Value-Form) can be used to exit the form, returning the
68 result of Value-Form."
69 (unless (symbolp name)
70 (compiler-error "The block name ~S is not a symbol." name))
71 (continuation-starts-block cont)
72 (let* ((dummy (make-continuation))
74 (cleanup (make-cleanup :kind :block
76 (push entry (lambda-entries (lexenv-lambda *lexenv*)))
77 (setf (entry-cleanup entry) cleanup)
78 (link-node-to-previous-continuation entry start)
79 (use-continuation entry dummy)
81 (let* ((env-entry (list entry cont))
82 (*lexenv* (make-lexenv :blocks (list (cons name env-entry))
84 (push env-entry (continuation-lexenv-uses cont))
85 (ir1-convert-progn-body dummy cont forms))))
88 (def-ir1-translator return-from ((name &optional value) start cont)
90 "Return-From Block-Name Value-Form
91 Evaluate the Value-Form, returning its values from the lexically enclosing
92 BLOCK Block-Name. This is constrained to be used only within the dynamic
95 ;; We make CONT start a block just so that it will have a block
96 ;; assigned. People assume that when they pass a continuation into
97 ;; IR1-CONVERT as CONT, it will have a block when it is done.
98 ;; KLUDGE: Note that this block is basically fictitious. In the code
99 ;; (BLOCK B (RETURN-FROM B) (SETQ X 3))
100 ;; it's the block which answers the question "which block is
101 ;; the (SETQ X 3) in?" when the right answer is that (SETQ X 3) is
102 ;; dead code and so doesn't really have a block at all. The existence
103 ;; of this block, and that way that it doesn't explicitly say
104 ;; "I'm actually nowhere at all" makes some logic (e.g.
105 ;; BLOCK-HOME-LAMBDA-OR-NULL) more obscure, and it might be better
106 ;; to get rid of it, perhaps using a special placeholder value
107 ;; to indicate the orphanedness of the code.
108 (continuation-starts-block cont)
109 (let* ((found (or (lexenv-find name blocks)
110 (compiler-error "return for unknown block: ~S" name)))
111 (value-cont (make-continuation))
112 (entry (first found))
113 (exit (make-exit :entry entry
115 (push exit (entry-exits entry))
116 (setf (continuation-dest value-cont) exit)
117 (ir1-convert start value-cont value)
118 (link-node-to-previous-continuation exit value-cont)
119 (let ((home-lambda (continuation-home-lambda-or-null start)))
121 (push entry (lambda-calls-or-closes home-lambda))))
122 (use-continuation exit (second found))))
124 ;;; Return a list of the segments of a TAGBODY. Each segment looks
125 ;;; like (<tag> <form>* (go <next tag>)). That is, we break up the
126 ;;; tagbody into segments of non-tag statements, and explicitly
127 ;;; represent the drop-through with a GO. The first segment has a
128 ;;; dummy NIL tag, since it represents code before the first tag. The
129 ;;; last segment (which may also be the first segment) ends in NIL
130 ;;; rather than a GO.
131 (defun parse-tagbody (body)
132 (declare (list body))
133 (collect ((segments))
134 (let ((current (cons nil body)))
136 (let ((tag-pos (position-if (complement #'listp) current :start 1)))
138 (segments `(,@current nil))
140 (let ((tag (elt current tag-pos)))
141 (when (assoc tag (segments))
143 "The tag ~S appears more than once in the tagbody."
145 (unless (or (symbolp tag) (integerp tag))
146 (compiler-error "~S is not a legal tagbody statement." tag))
147 (segments `(,@(subseq current 0 tag-pos) (go ,tag))))
148 (setq current (nthcdr tag-pos current)))))
151 ;;; Set up the cleanup, emitting the entry node. Then make a block for
152 ;;; each tag, building up the tag list for LEXENV-TAGS as we go.
153 ;;; Finally, convert each segment with the precomputed Start and Cont
155 (def-ir1-translator tagbody ((&rest statements) start cont)
157 "Tagbody {Tag | Statement}*
158 Define tags for used with GO. The Statements are evaluated in order
159 (skipping Tags) and NIL is returned. If a statement contains a GO to a
160 defined Tag within the lexical scope of the form, then control is transferred
161 to the next statement following that tag. A Tag must an integer or a
162 symbol. A statement must be a list. Other objects are illegal within the
164 (continuation-starts-block cont)
165 (let* ((dummy (make-continuation))
167 (segments (parse-tagbody statements))
168 (cleanup (make-cleanup :kind :tagbody
170 (push entry (lambda-entries (lexenv-lambda *lexenv*)))
171 (setf (entry-cleanup entry) cleanup)
172 (link-node-to-previous-continuation entry start)
173 (use-continuation entry dummy)
179 (dolist (segment (rest segments))
180 (let* ((tag-cont (make-continuation))
181 (tag (list (car segment) entry tag-cont)))
184 (continuation-starts-block tag-cont)
186 (push (cdr tag) (continuation-lexenv-uses tag-cont))))
189 (let ((*lexenv* (make-lexenv :cleanup cleanup :tags (tags))))
190 (mapc (lambda (segment start cont)
191 (ir1-convert-progn-body start cont (rest segment)))
192 segments (starts) (conts))))))
194 ;;; Emit an EXIT node without any value.
195 (def-ir1-translator go ((tag) start cont)
198 Transfer control to the named Tag in the lexically enclosing TAGBODY. This
199 is constrained to be used only within the dynamic extent of the TAGBODY."
200 (continuation-starts-block cont)
201 (let* ((found (or (lexenv-find tag tags :test #'eql)
202 (compiler-error "attempt to GO to nonexistent tag: ~S"
204 (entry (first found))
205 (exit (make-exit :entry entry)))
206 (push exit (entry-exits entry))
207 (link-node-to-previous-continuation exit start)
208 (let ((home-lambda (continuation-home-lambda-or-null start)))
210 (push entry (lambda-calls-or-closes home-lambda))))
211 (use-continuation exit (second found))))
213 ;;;; translators for compiler-magic special forms
215 ;;; This handles EVAL-WHEN in non-top-level forms. (EVAL-WHENs in top
216 ;;; level forms are picked off and handled by PROCESS-TOPLEVEL-FORM,
217 ;;; so that they're never seen at this level.)
219 ;;; ANSI "3.2.3.1 Processing of Top Level Forms" says that processing
220 ;;; of non-top-level EVAL-WHENs is very simple:
221 ;;; EVAL-WHEN forms cause compile-time evaluation only at top level.
222 ;;; Both :COMPILE-TOPLEVEL and :LOAD-TOPLEVEL situation specifications
223 ;;; are ignored for non-top-level forms. For non-top-level forms, an
224 ;;; eval-when specifying the :EXECUTE situation is treated as an
225 ;;; implicit PROGN including the forms in the body of the EVAL-WHEN
226 ;;; form; otherwise, the forms in the body are ignored.
227 (def-ir1-translator eval-when ((situations &rest forms) start cont)
229 "EVAL-WHEN (Situation*) Form*
230 Evaluate the Forms in the specified Situations (any of :COMPILE-TOPLEVEL,
231 :LOAD-TOPLEVEL, or :EXECUTE, or (deprecated) COMPILE, LOAD, or EVAL)."
232 (multiple-value-bind (ct lt e) (parse-eval-when-situations situations)
233 (declare (ignore ct lt))
234 (ir1-convert-progn-body start cont (and e forms)))
237 ;;; common logic for MACROLET and SYMBOL-MACROLET
239 ;;; Call DEFINITIONIZE-FUN on each element of DEFINITIONS to find its
240 ;;; in-lexenv representation, stuff the results into *LEXENV*, and
241 ;;; call FUN (with no arguments).
242 (defun %funcall-in-foomacrolet-lexenv (definitionize-fun
243 definitionize-keyword
246 (declare (type function definitionize-fun fun))
247 (declare (type (member :vars :funs) definitionize-keyword))
248 (declare (type list definitions))
249 (unless (= (length definitions)
250 (length (remove-duplicates definitions :key #'first)))
251 (compiler-style-warn "duplicate definitions in ~S" definitions))
252 (let* ((processed-definitions (mapcar definitionize-fun definitions))
253 (*lexenv* (make-lexenv definitionize-keyword processed-definitions)))
256 ;;; Tweak *LEXENV* to include the DEFINITIONS from a MACROLET, then
257 ;;; call FUN (with no arguments).
259 ;;; This is split off from the IR1 convert method so that it can be
260 ;;; shared by the special-case top level MACROLET processing code.
261 (defun funcall-in-macrolet-lexenv (definitions fun)
262 (%funcall-in-foomacrolet-lexenv
264 (unless (list-of-length-at-least-p definition 2)
266 "The list ~S is too short to be a legal local macro definition."
268 (destructuring-bind (name arglist &body body) definition
269 (unless (symbolp name)
270 (compiler-error "The local macro name ~S is not a symbol." name))
271 (let ((whole (gensym "WHOLE"))
272 (environment (gensym "ENVIRONMENT")))
273 (multiple-value-bind (body local-decls)
274 (parse-defmacro arglist whole body name 'macrolet
275 :environment environment)
278 `(lambda (,whole ,environment)
280 (block ,name ,body))))))))
285 (def-ir1-translator macrolet ((definitions &rest body) start cont)
287 "MACROLET ({(Name Lambda-List Form*)}*) Body-Form*
288 Evaluate the Body-Forms in an environment with the specified local macros
289 defined. Name is the local macro name, Lambda-List is the DEFMACRO style
290 destructuring lambda list, and the Forms evaluate to the expansion. The
291 Forms are evaluated in the null environment."
292 (funcall-in-macrolet-lexenv definitions
294 (ir1-translate-locally body start cont))))
296 (defun funcall-in-symbol-macrolet-lexenv (definitions fun)
297 (%funcall-in-foomacrolet-lexenv
299 (unless (proper-list-of-length-p definition 2)
300 (compiler-error "malformed symbol/expansion pair: ~S" definition))
301 (destructuring-bind (name expansion) definition
302 (unless (symbolp name)
304 "The local symbol macro name ~S is not a symbol."
306 `(,name . (MACRO . ,expansion))))
311 (def-ir1-translator symbol-macrolet ((macrobindings &body body) start cont)
313 "SYMBOL-MACROLET ({(Name Expansion)}*) Decl* Form*
314 Define the Names as symbol macros with the given Expansions. Within the
315 body, references to a Name will effectively be replaced with the Expansion."
316 (funcall-in-symbol-macrolet-lexenv
319 (ir1-translate-locally body start cont))))
321 ;;; not really a special form, but..
322 (def-ir1-translator declare ((&rest stuff) start cont)
323 (declare (ignore stuff))
324 ;; We ignore START and CONT too, but we can't use DECLARE IGNORE to
325 ;; tell the compiler about it here, because the DEF-IR1-TRANSLATOR
326 ;; macro would put the DECLARE in the wrong place, so..
328 (compiler-error "misplaced declaration"))
332 ;;;; Uses of %PRIMITIVE are either expanded into Lisp code or turned
333 ;;;; into a funny function.
335 ;;; Carefully evaluate a list of forms, returning a list of the results.
336 (defun eval-info-args (args)
337 (declare (list args))
338 (handler-case (mapcar #'eval args)
340 (compiler-error "Lisp error during evaluation of info args:~%~A"
343 ;;; Convert to the %%PRIMITIVE funny function. The first argument is
344 ;;; the template, the second is a list of the results of any
345 ;;; codegen-info args, and the remaining arguments are the runtime
348 ;;; We do various error checking now so that we don't bomb out with
349 ;;; a fatal error during IR2 conversion.
351 ;;; KLUDGE: It's confusing having multiple names floating around for
352 ;;; nearly the same concept: PRIMITIVE, TEMPLATE, VOP. Now that CMU
353 ;;; CL's *PRIMITIVE-TRANSLATORS* stuff is gone, we could call
354 ;;; primitives VOPs, rename TEMPLATE to VOP-TEMPLATE, rename
355 ;;; BACKEND-TEMPLATE-NAMES to BACKEND-VOPS, and rename %PRIMITIVE to
356 ;;; VOP or %VOP.. -- WHN 2001-06-11
357 ;;; FIXME: Look at doing this ^, it doesn't look too hard actually.
358 (def-ir1-translator %primitive ((name &rest args) start cont)
359 (unless (symbolp name)
360 (compiler-error "internal error: Primitive name ~S is not a symbol." name))
361 (let* ((template (or (gethash name *backend-template-names*)
363 "internal error: Primitive name ~A is not defined."
365 (required (length (template-arg-types template)))
366 (info (template-info-arg-count template))
367 (min (+ required info))
368 (nargs (length args)))
369 (if (template-more-args-type template)
371 (compiler-error "internal error: Primitive ~A was called ~
372 with ~R argument~:P, ~
373 but wants at least ~R."
377 (unless (= nargs min)
378 (compiler-error "internal error: Primitive ~A was called ~
379 with ~R argument~:P, ~
380 but wants exactly ~R."
385 (when (eq (template-result-types template) :conditional)
387 "%PRIMITIVE was used with a conditional template."))
389 (when (template-more-results-type template)
391 "%PRIMITIVE was used with an unknown values template."))
395 `(%%primitive ',template
397 (subseq args required min))
398 ,@(subseq args 0 required)
399 ,@(subseq args min)))))
403 (def-ir1-translator quote ((thing) start cont)
406 Return Value without evaluating it."
407 (reference-constant start cont thing))
409 ;;;; FUNCTION and NAMED-LAMBDA
411 (def-ir1-translator function ((thing) start cont)
414 Return the lexically apparent definition of the function Name. Name may also
415 be a lambda expression."
419 (reference-leaf start
421 (ir1-convert-lambda thing
422 :debug-name (debug-namify
425 (let ((var (find-lexically-apparent-fun
426 thing "as the argument to FUNCTION")))
427 (reference-leaf start cont var)))
429 (let ((res (ir1-convert-lambda `(lambda ,@(cdr thing))
430 :debug-name (debug-namify "#'~S"
432 (setf (getf (functional-plist res) :fin-function) t)
433 (reference-leaf start cont res)))
435 (compiler-error "~S is not a legal function name." thing)))
436 (let ((var (find-lexically-apparent-fun
437 thing "as the argument to FUNCTION")))
438 (reference-leaf start cont var))))
440 ;;; `(NAMED-LAMBDA ,NAME ,@REST) is like `(FUNCTION (LAMBDA ,@REST)),
441 ;;; except that the value of NAME is passed to the compiler for use in
442 ;;; creation of debug information for the resulting function.
444 ;;; NAME can be a legal function name or some arbitrary other thing.
446 ;;; If NAME is a legal function name, then the caller should be
447 ;;; planning to set (FDEFINITION NAME) to the created function.
448 ;;; (Otherwise the debug names will be inconsistent and thus
449 ;;; unnecessarily confusing.)
451 ;;; Arbitrary other things are appropriate for naming things which are
452 ;;; not the FDEFINITION of NAME. E.g.
453 ;;; NAME = (:FLET FOO BAR)
454 ;;; for the FLET function in
456 ;;; (FLET ((FOO (Y) (+ X Y)))
459 ;;; NAME = (:METHOD PRINT-OBJECT :AROUND (STARSHIP T))
460 ;;; for the function used to implement
461 ;;; (DEFMETHOD PRINT-OBJECT :AROUND ((SS STARSHIP) STREAM) ...).
462 (def-ir1-translator named-lambda ((name &rest rest) start cont)
463 (reference-leaf start
465 (if (legal-fun-name-p name)
466 (ir1-convert-lambda `(lambda ,@rest)
468 (ir1-convert-lambda `(lambda ,@rest)
473 ;;; FUNCALL is implemented on %FUNCALL, which can only call functions
474 ;;; (not symbols). %FUNCALL is used directly in some places where the
475 ;;; call should always be open-coded even if FUNCALL is :NOTINLINE.
476 (deftransform funcall ((function &rest args) * * :when :both)
477 (let ((arg-names (make-gensym-list (length args))))
478 `(lambda (function ,@arg-names)
479 (%funcall ,(if (csubtypep (continuation-type function)
480 (specifier-type 'function))
482 '(%coerce-callable-to-fun function))
485 (def-ir1-translator %funcall ((function &rest args) start cont)
486 (let ((fun-cont (make-continuation)))
487 (ir1-convert start fun-cont function)
488 (assert-continuation-type fun-cont (specifier-type 'function))
489 (ir1-convert-combination-args fun-cont cont args)))
491 ;;; This source transform exists to reduce the amount of work for the
492 ;;; compiler. If the called function is a FUNCTION form, then convert
493 ;;; directly to %FUNCALL, instead of waiting around for type
495 (define-source-transform funcall (function &rest args)
496 (if (and (consp function) (eq (car function) 'function))
497 `(%funcall ,function ,@args)
500 (deftransform %coerce-callable-to-fun ((thing) (function) *
503 "optimize away possible call to FDEFINITION at runtime"
508 ;;;; (LET and LET* can't be implemented as macros due to the fact that
509 ;;;; any pervasive declarations also affect the evaluation of the
512 ;;; Given a list of binding specifiers in the style of Let, return:
513 ;;; 1. The list of var structures for the variables bound.
514 ;;; 2. The initial value form for each variable.
516 ;;; The variable names are checked for legality and globally special
517 ;;; variables are marked as such. Context is the name of the form, for
518 ;;; error reporting purposes.
519 (declaim (ftype (function (list symbol) (values list list list))
521 (defun extract-let-vars (bindings context)
525 (flet ((get-var (name)
526 (varify-lambda-arg name
527 (if (eq context 'let*)
530 (dolist (spec bindings)
532 (let ((var (get-var spec)))
534 (names (cons spec var))
537 (unless (proper-list-of-length-p spec 1 2)
538 (compiler-error "The ~S binding spec ~S is malformed."
541 (let* ((name (first spec))
542 (var (get-var name)))
545 (vals (second spec)))))))
547 (values (vars) (vals) (names))))
549 (def-ir1-translator let ((bindings &body body)
552 "LET ({(Var [Value]) | Var}*) Declaration* Form*
553 During evaluation of the Forms, bind the Vars to the result of evaluating the
554 Value forms. The variables are bound in parallel after all of the Values are
556 (multiple-value-bind (forms decls) (sb!sys:parse-body body nil)
557 (multiple-value-bind (vars values) (extract-let-vars bindings 'let)
558 (let* ((*lexenv* (process-decls decls vars nil cont))
559 (fun-cont (make-continuation))
560 (fun (ir1-convert-lambda-body
561 forms vars :debug-name (debug-namify "LET ~S" bindings))))
562 (reference-leaf start fun-cont fun)
563 (ir1-convert-combination-args fun-cont cont values)))))
565 (def-ir1-translator let* ((bindings &body body)
568 "LET* ({(Var [Value]) | Var}*) Declaration* Form*
569 Similar to LET, but the variables are bound sequentially, allowing each Value
570 form to reference any of the previous Vars."
571 (multiple-value-bind (forms decls) (sb!sys:parse-body body nil)
572 (multiple-value-bind (vars values) (extract-let-vars bindings 'let*)
573 (let ((*lexenv* (process-decls decls vars nil cont)))
574 (ir1-convert-aux-bindings start cont forms vars values)))))
576 ;;; logic shared between IR1 translators for LOCALLY, MACROLET,
577 ;;; and SYMBOL-MACROLET
579 ;;; Note that all these things need to preserve toplevel-formness,
580 ;;; but we don't need to worry about that within an IR1 translator,
581 ;;; since toplevel-formness is picked off by PROCESS-TOPLEVEL-FOO
582 ;;; forms before we hit the IR1 transform level.
583 (defun ir1-translate-locally (body start cont)
584 (declare (type list body) (type continuation start cont))
585 (multiple-value-bind (forms decls) (sb!sys:parse-body body nil)
586 (let ((*lexenv* (process-decls decls nil nil cont)))
587 (ir1-convert-aux-bindings start cont forms nil nil))))
589 (def-ir1-translator locally ((&body body) start cont)
591 "LOCALLY Declaration* Form*
592 Sequentially evaluate the Forms in a lexical environment where the
593 the Declarations have effect. If LOCALLY is a top level form, then
594 the Forms are also processed as top level forms."
595 (ir1-translate-locally body start cont))
599 ;;; Given a list of local function specifications in the style of
600 ;;; FLET, return lists of the function names and of the lambdas which
601 ;;; are their definitions.
603 ;;; The function names are checked for legality. CONTEXT is the name
604 ;;; of the form, for error reporting.
605 (declaim (ftype (function (list symbol) (values list list)) extract-flet-vars))
606 (defun extract-flet-vars (definitions context)
609 (dolist (def definitions)
610 (when (or (atom def) (< (length def) 2))
611 (compiler-error "The ~S definition spec ~S is malformed." context def))
613 (let ((name (first def)))
614 (check-fun-name name)
616 (multiple-value-bind (forms decls) (sb!sys:parse-body (cddr def))
617 (defs `(lambda ,(second def)
619 (block ,(fun-name-block-name name)
621 (values (names) (defs))))
623 (def-ir1-translator flet ((definitions &body body)
626 "FLET ({(Name Lambda-List Declaration* Form*)}*) Declaration* Body-Form*
627 Evaluate the Body-Forms with some local function definitions. The bindings
628 do not enclose the definitions; any use of Name in the Forms will refer to
629 the lexically apparent function definition in the enclosing environment."
630 (multiple-value-bind (forms decls) (sb!sys:parse-body body nil)
631 (multiple-value-bind (names defs)
632 (extract-flet-vars definitions 'flet)
633 (let* ((fvars (mapcar (lambda (n d)
634 (ir1-convert-lambda d
636 :debug-name (debug-namify
639 (*lexenv* (make-lexenv
640 :default (process-decls decls nil fvars cont)
641 :funs (pairlis names fvars))))
642 (ir1-convert-progn-body start cont forms)))))
644 (def-ir1-translator labels ((definitions &body body) start cont)
646 "LABELS ({(Name Lambda-List Declaration* Form*)}*) Declaration* Body-Form*
647 Evaluate the Body-Forms with some local function definitions. The bindings
648 enclose the new definitions, so the defined functions can call themselves or
650 (multiple-value-bind (forms decls) (sb!sys:parse-body body nil)
651 (multiple-value-bind (names defs)
652 (extract-flet-vars definitions 'labels)
653 (let* (;; dummy LABELS functions, to be used as placeholders
654 ;; during construction of real LABELS functions
655 (placeholder-funs (mapcar (lambda (name)
658 :%debug-name (debug-namify
659 "LABELS placeholder ~S"
662 ;; (like PAIRLIS but guaranteed to preserve ordering:)
663 (placeholder-fenv (mapcar #'cons names placeholder-funs))
664 ;; the real LABELS functions, compiled in a LEXENV which
665 ;; includes the dummy LABELS functions
667 (let ((*lexenv* (make-lexenv :funs placeholder-fenv)))
668 (mapcar (lambda (name def)
669 (ir1-convert-lambda def
671 :debug-name (debug-namify
675 ;; Modify all the references to the dummy function leaves so
676 ;; that they point to the real function leaves.
677 (loop for real-fun in real-funs and
678 placeholder-cons in placeholder-fenv do
679 (substitute-leaf real-fun (cdr placeholder-cons))
680 (setf (cdr placeholder-cons) real-fun))
683 (let ((*lexenv* (make-lexenv
684 :default (process-decls decls nil real-funs cont)
685 ;; Use a proper FENV here (not the
686 ;; placeholder used earlier) so that if the
687 ;; lexical environment is used for inline
688 ;; expansion we'll get the right functions.
689 :funs (pairlis names real-funs))))
690 (ir1-convert-progn-body start cont forms))))))
692 ;;;; the THE special operator, and friends
694 ;;; Do stuff to recognize a THE or VALUES declaration. CONT is the
695 ;;; continuation that the assertion applies to, TYPE is the type
696 ;;; specifier and LEXENV is the current lexical environment. NAME is
697 ;;; the name of the declaration we are doing, for use in error
700 ;;; This is somewhat involved, since a type assertion may only be made
701 ;;; on a continuation, not on a node. We can't just set the
702 ;;; continuation asserted type and let it go at that, since there may
703 ;;; be parallel THE's for the same continuation, i.e.
708 ;;; In this case, our representation can do no better than the union
709 ;;; of these assertions. And if there is a branch with no assertion,
710 ;;; we have nothing at all. We really need to recognize scoping, since
711 ;;; we need to be able to discern between parallel assertions (which
712 ;;; we union) and nested ones (which we intersect).
714 ;;; We represent the scoping by throwing our innermost (intersected)
715 ;;; assertion on CONT into the TYPE-RESTRICTIONS. As we go down, we
716 ;;; intersect our assertions together. If CONT has no uses yet, we
717 ;;; have not yet bottomed out on the first COND branch; in this case
718 ;;; we optimistically assume that this type will be the one we end up
719 ;;; with, and set the ASSERTED-TYPE to it. We can never get better
720 ;;; than the type that we have the first time we bottom out. Later
721 ;;; THE's (or the absence thereof) can only weaken this result.
723 ;;; We make this work by getting USE-CONTINUATION to do the unioning
724 ;;; across COND branches. We can't do it here, since we don't know how
725 ;;; many branches there are going to be.
726 (defun ir1ize-the-or-values (type cont lexenv name)
727 (declare (type continuation cont) (type lexenv lexenv))
728 (let* ((ctype (values-specifier-type type))
729 (old-type (or (lexenv-find cont type-restrictions)
731 (intersects (values-types-equal-or-intersect old-type ctype))
732 (int (values-type-intersection old-type ctype))
733 (new (if intersects int old-type)))
734 (when (null (find-uses cont))
735 (setf (continuation-asserted-type cont) new))
736 (when (and (not intersects)
737 (not (policy *lexenv*
738 (= inhibit-warnings 3)))) ;FIXME: really OK to suppress?
740 "The type ~S in ~S declaration conflicts with an ~
741 enclosing assertion:~% ~S"
742 (type-specifier ctype)
744 (type-specifier old-type)))
745 (make-lexenv :type-restrictions `((,cont . ,new))
748 ;;; Assert that FORM evaluates to the specified type (which may be a
751 ;;; FIXME: In a version of CMU CL that I used at Cadabra ca. 20000101,
752 ;;; this didn't seem to expand into an assertion, at least for ALIEN
753 ;;; values. Check that SBCL doesn't have this problem.
754 (def-ir1-translator the ((type value) start cont)
755 (let ((*lexenv* (ir1ize-the-or-values type cont *lexenv* 'the)))
756 (ir1-convert start cont value)))
758 ;;; This is like the THE special form, except that it believes
759 ;;; whatever you tell it. It will never generate a type check, but
760 ;;; will cause a warning if the compiler can prove the assertion is
763 ;;; Since the CONTINUATION-DERIVED-TYPE is computed as the union of
764 ;;; its uses's types, setting it won't work. Instead we must intersect
765 ;;; the type with the uses's DERIVED-TYPE.
766 (def-ir1-translator truly-the ((type value) start cont)
768 (declare (inline member))
769 (let ((type (values-specifier-type type))
770 (old (find-uses cont)))
771 (ir1-convert start cont value)
773 (unless (member use old :test #'eq)
774 (derive-node-type use type)))))
778 ;;; If there is a definition in LEXENV-VARS, just set that, otherwise
779 ;;; look at the global information. If the name is for a constant,
781 (def-ir1-translator setq ((&whole source &rest things) start cont)
782 (let ((len (length things)))
784 (compiler-error "odd number of args to SETQ: ~S" source))
786 (let* ((name (first things))
787 (leaf (or (lexenv-find name vars)
788 (find-free-var name))))
791 (when (constant-p leaf)
792 (compiler-error "~S is a constant and thus can't be set." name))
793 (when (lambda-var-p leaf)
794 (let ((home-lambda (continuation-home-lambda-or-null start)))
796 (pushnew leaf (lambda-calls-or-closes home-lambda))))
797 (when (lambda-var-ignorep leaf)
798 ;; ANSI's definition of "Declaration IGNORE, IGNORABLE"
799 ;; requires that this be a STYLE-WARNING, not a full warning.
801 "~S is being set even though it was declared to be ignored."
803 (setq-var start cont leaf (second things)))
805 (aver (eq (car leaf) 'MACRO))
806 (ir1-convert start cont `(setf ,(cdr leaf) ,(second things))))
808 (ir1-convert start cont
809 `(%set-heap-alien ',leaf ,(second things))))))
811 (do ((thing things (cddr thing)))
813 (ir1-convert-progn-body start cont (sets)))
814 (sets `(setq ,(first thing) ,(second thing))))))))
816 ;;; This is kind of like REFERENCE-LEAF, but we generate a SET node.
817 ;;; This should only need to be called in SETQ.
818 (defun setq-var (start cont var value)
819 (declare (type continuation start cont) (type basic-var var))
820 (let ((dest (make-continuation)))
821 (setf (continuation-asserted-type dest) (leaf-type var))
822 (ir1-convert start dest value)
823 (let ((res (make-set :var var :value dest)))
824 (setf (continuation-dest dest) res)
825 (setf (leaf-ever-used var) t)
826 (push res (basic-var-sets var))
827 (link-node-to-previous-continuation res dest)
828 (use-continuation res cont))))
830 ;;;; CATCH, THROW and UNWIND-PROTECT
832 ;;; We turn THROW into a multiple-value-call of a magical function,
833 ;;; since as as far as IR1 is concerned, it has no interesting
834 ;;; properties other than receiving multiple-values.
835 (def-ir1-translator throw ((tag result) start cont)
838 Do a non-local exit, return the values of Form from the CATCH whose tag
839 evaluates to the same thing as Tag."
840 (ir1-convert start cont
841 `(multiple-value-call #'%throw ,tag ,result)))
843 ;;; This is a special special form used to instantiate a cleanup as
844 ;;; the current cleanup within the body. KIND is the kind of cleanup
845 ;;; to make, and MESS-UP is a form that does the mess-up action. We
846 ;;; make the MESS-UP be the USE of the MESS-UP form's continuation,
847 ;;; and introduce the cleanup into the lexical environment. We
848 ;;; back-patch the ENTRY-CLEANUP for the current cleanup to be the new
849 ;;; cleanup, since this inner cleanup is the interesting one.
850 (def-ir1-translator %within-cleanup ((kind mess-up &body body) start cont)
851 (let ((dummy (make-continuation))
852 (dummy2 (make-continuation)))
853 (ir1-convert start dummy mess-up)
854 (let* ((mess-node (continuation-use dummy))
855 (cleanup (make-cleanup :kind kind
857 (old-cup (lexenv-cleanup *lexenv*))
858 (*lexenv* (make-lexenv :cleanup cleanup)))
859 (setf (entry-cleanup (cleanup-mess-up old-cup)) cleanup)
860 (ir1-convert dummy dummy2 '(%cleanup-point))
861 (ir1-convert-progn-body dummy2 cont body))))
863 ;;; This is a special special form that makes an "escape function"
864 ;;; which returns unknown values from named block. We convert the
865 ;;; function, set its kind to :ESCAPE, and then reference it. The
866 ;;; :ESCAPE kind indicates that this function's purpose is to
867 ;;; represent a non-local control transfer, and that it might not
868 ;;; actually have to be compiled.
870 ;;; Note that environment analysis replaces references to escape
871 ;;; functions with references to the corresponding NLX-INFO structure.
872 (def-ir1-translator %escape-fun ((tag) start cont)
873 (let ((fun (ir1-convert-lambda
875 (return-from ,tag (%unknown-values)))
876 :debug-name (debug-namify "escape function for ~S" tag))))
877 (setf (functional-kind fun) :escape)
878 (reference-leaf start cont fun)))
880 ;;; Yet another special special form. This one looks up a local
881 ;;; function and smashes it to a :CLEANUP function, as well as
883 (def-ir1-translator %cleanup-fun ((name) start cont)
884 (let ((fun (lexenv-find name funs)))
885 (aver (lambda-p fun))
886 (setf (functional-kind fun) :cleanup)
887 (reference-leaf start cont fun)))
889 ;;; We represent the possibility of the control transfer by making an
890 ;;; "escape function" that does a lexical exit, and instantiate the
891 ;;; cleanup using %WITHIN-CLEANUP.
892 (def-ir1-translator catch ((tag &body body) start cont)
895 Evaluates Tag and instantiates it as a catcher while the body forms are
896 evaluated in an implicit PROGN. If a THROW is done to Tag within the dynamic
897 scope of the body, then control will be transferred to the end of the body
898 and the thrown values will be returned."
901 (let ((exit-block (gensym "EXIT-BLOCK-")))
905 (%catch (%escape-fun ,exit-block) ,tag)
908 ;;; UNWIND-PROTECT is similar to CATCH, but hairier. We make the
909 ;;; cleanup forms into a local function so that they can be referenced
910 ;;; both in the case where we are unwound and in any local exits. We
911 ;;; use %CLEANUP-FUN on this to indicate that reference by
912 ;;; %UNWIND-PROTECT isn't "real", and thus doesn't cause creation of
914 (def-ir1-translator unwind-protect ((protected &body cleanup) start cont)
916 "Unwind-Protect Protected Cleanup*
917 Evaluate the form Protected, returning its values. The cleanup forms are
918 evaluated whenever the dynamic scope of the Protected form is exited (either
919 due to normal completion or a non-local exit such as THROW)."
922 (let ((cleanup-fun (gensym "CLEANUP-FUN-"))
923 (drop-thru-tag (gensym "DROP-THRU-TAG-"))
924 (exit-tag (gensym "EXIT-TAG-"))
925 (next (gensym "NEXT"))
926 (start (gensym "START"))
927 (count (gensym "COUNT")))
928 `(flet ((,cleanup-fun () ,@cleanup nil))
929 ;; FIXME: If we ever get DYNAMIC-EXTENT working, then
930 ;; ,CLEANUP-FUN should probably be declared DYNAMIC-EXTENT,
931 ;; and something can be done to make %ESCAPE-FUN have
932 ;; dynamic extent too.
933 (block ,drop-thru-tag
934 (multiple-value-bind (,next ,start ,count)
938 (%unwind-protect (%escape-fun ,exit-tag)
939 (%cleanup-fun ,cleanup-fun))
940 (return-from ,drop-thru-tag ,protected)))
942 (%continue-unwind ,next ,start ,count)))))))
944 ;;;; multiple-value stuff
946 ;;; If there are arguments, MULTIPLE-VALUE-CALL turns into an
949 ;;; If there are no arguments, then we convert to a normal
950 ;;; combination, ensuring that a MV-COMBINATION always has at least
951 ;;; one argument. This can be regarded as an optimization, but it is
952 ;;; more important for simplifying compilation of MV-COMBINATIONS.
953 (def-ir1-translator multiple-value-call ((fun &rest args) start cont)
955 "MULTIPLE-VALUE-CALL Function Values-Form*
956 Call Function, passing all the values of each Values-Form as arguments,
957 values from the first Values-Form making up the first argument, etc."
958 (let* ((fun-cont (make-continuation))
960 (make-mv-combination fun-cont)
961 (make-combination fun-cont))))
962 (ir1-convert start fun-cont
963 (if (and (consp fun) (eq (car fun) 'function))
965 `(%coerce-callable-to-fun ,fun)))
966 (setf (continuation-dest fun-cont) node)
967 (assert-continuation-type fun-cont
968 (specifier-type '(or function symbol)))
969 (collect ((arg-conts))
970 (let ((this-start fun-cont))
972 (let ((this-cont (make-continuation node)))
973 (ir1-convert this-start this-cont arg)
974 (setq this-start this-cont)
975 (arg-conts this-cont)))
976 (link-node-to-previous-continuation node this-start)
977 (use-continuation node cont)
978 (setf (basic-combination-args node) (arg-conts))))))
980 ;;; MULTIPLE-VALUE-PROG1 is represented implicitly in IR1 by having a
981 ;;; the result code use result continuation (CONT), but transfer
982 ;;; control to the evaluation of the body. In other words, the result
983 ;;; continuation isn't IMMEDIATELY-USED-P by the nodes that compute
986 ;;; In order to get the control flow right, we convert the result with
987 ;;; a dummy result continuation, then convert all the uses of the
988 ;;; dummy to be uses of CONT. If a use is an EXIT, then we also
989 ;;; substitute CONT for the dummy in the corresponding ENTRY node so
990 ;;; that they are consistent. Note that this doesn't amount to
991 ;;; changing the exit target, since the control destination of an exit
992 ;;; is determined by the block successor; we are just indicating the
993 ;;; continuation that the result is delivered to.
995 ;;; We then convert the body, using another dummy continuation in its
996 ;;; own block as the result. After we are done converting the body, we
997 ;;; move all predecessors of the dummy end block to CONT's block.
999 ;;; Note that we both exploit and maintain the invariant that the CONT
1000 ;;; to an IR1 convert method either has no block or starts the block
1001 ;;; that control should transfer to after completion for the form.
1002 ;;; Nested MV-PROG1's work because during conversion of the result
1003 ;;; form, we use dummy continuation whose block is the true control
1005 (def-ir1-translator multiple-value-prog1 ((result &rest forms) start cont)
1007 "MULTIPLE-VALUE-PROG1 Values-Form Form*
1008 Evaluate Values-Form and then the Forms, but return all the values of
1010 (continuation-starts-block cont)
1011 (let* ((dummy-result (make-continuation))
1012 (dummy-start (make-continuation))
1013 (cont-block (continuation-block cont)))
1014 (continuation-starts-block dummy-start)
1015 (ir1-convert start dummy-start result)
1017 (substitute-continuation-uses cont dummy-start)
1019 (continuation-starts-block dummy-result)
1020 (ir1-convert-progn-body dummy-start dummy-result forms)
1021 (let ((end-block (continuation-block dummy-result)))
1022 (dolist (pred (block-pred end-block))
1023 (unlink-blocks pred end-block)
1024 (link-blocks pred cont-block))
1025 (aver (not (continuation-dest dummy-result)))
1026 (delete-continuation dummy-result)
1027 (remove-from-dfo end-block))))
1029 ;;;; interface to defining macros
1032 ;;;; classic CMU CL comment:
1033 ;;;; DEFMACRO and DEFUN expand into calls to %DEFxxx functions
1034 ;;;; so that we get a chance to see what is going on. We define
1035 ;;;; IR1 translators for these functions which look at the
1036 ;;;; definition and then generate a call to the %%DEFxxx function.
1037 ;;;; Alas, this implementation doesn't do the right thing for
1038 ;;;; non-toplevel uses of these forms, so this should probably
1039 ;;;; be changed to use EVAL-WHEN instead.
1041 ;;; Return a new source path with any stuff intervening between the
1042 ;;; current path and the first form beginning with NAME stripped off.
1043 ;;; This is used to hide the guts of DEFmumble macros to prevent
1044 ;;; annoying error messages.
1045 (defun revert-source-path (name)
1046 (do ((path *current-path* (cdr path)))
1047 ((null path) *current-path*)
1048 (let ((first (first path)))
1049 (when (or (eq first name)
1050 (eq first 'original-source-start))
1053 ;;; Warn about incompatible or illegal definitions and add the macro
1054 ;;; to the compiler environment.
1056 ;;; Someday we could check for macro arguments being incompatibly
1057 ;;; redefined. Doing this right will involve finding the old macro
1058 ;;; lambda-list and comparing it with the new one.
1059 (def-ir1-translator %defmacro ((qname qdef lambda-list doc) start cont
1061 (let (;; QNAME is typically a quoted name. I think the idea is to
1062 ;; let %DEFMACRO work as an ordinary function when
1063 ;; interpreting. Whatever the reason the quote is there, we
1064 ;; don't want it any more. -- WHN 19990603
1066 ;; QDEF should be a sharp-quoted definition. We don't want to
1067 ;; make a function of it just yet, so we just drop the
1070 (aver (eq 'function (first qdef)))
1071 (aver (proper-list-of-length-p qdef 2))
1074 (/show "doing IR1 translator for %DEFMACRO" name)
1076 (unless (symbolp name)
1077 (compiler-error "The macro name ~S is not a symbol." name))
1079 (ecase (info :function :kind name)
1082 (remhash name *free-funs*)
1083 (undefine-fun-name name)
1085 "~S is being redefined as a macro when it was ~
1086 previously ~(~A~) to be a function."
1088 (info :function :where-from name)))
1091 (compiler-error "The special form ~S can't be redefined as a macro."
1094 (setf (info :function :kind name) :macro
1095 (info :function :where-from name) :defined
1096 (info :function :macro-function name) (coerce def 'function))
1098 (let* ((*current-path* (revert-source-path 'defmacro))
1099 (fun (ir1-convert-lambda def
1100 :debug-name (debug-namify "DEFMACRO ~S"
1102 (setf (functional-arg-documentation fun) (eval lambda-list))
1104 (ir1-convert start cont `(%%defmacro ',name ,fun ,doc)))
1106 (when sb!xc:*compile-print*
1107 ;; FIXME: It would be nice to convert this, and the other places
1108 ;; which create compiler diagnostic output prefixed by
1109 ;; semicolons, to use some common utility which automatically
1110 ;; prefixes all its output with semicolons. (The addition of
1111 ;; semicolon prefixes was introduced ca. sbcl-0.6.8.10 as the
1112 ;; "MNA compiler message patch", and implemented by modifying a
1113 ;; bunch of output statements on a case-by-case basis, which
1114 ;; seems unnecessarily error-prone and unclear, scattering
1115 ;; implicit information about output style throughout the
1116 ;; system.) Starting by rewriting COMPILER-MUMBLE to add
1117 ;; semicolon prefixes would be a good start, and perhaps also:
1118 ;; * Add semicolon prefixes for "FOO assembled" messages emitted
1119 ;; when e.g. src/assembly/x86/assem-rtns.lisp is processed.
1120 ;; * At least some debugger output messages deserve semicolon
1122 ;; ** restarts table
1123 ;; ** "Within the debugger, you can type HELP for help."
1124 (compiler-mumble "~&; converted ~S~%" name))))
1126 (def-ir1-translator %define-compiler-macro ((name def lambda-list doc)
1129 (let ((name (eval name))
1130 (def (second def))) ; We don't want to make a function just yet...
1132 (when (eq (info :function :kind name) :special-form)
1133 (compiler-error "attempt to define a compiler-macro for special form ~S"
1136 (setf (info :function :compiler-macro-function name)
1137 (coerce def 'function))
1139 (let* ((*current-path* (revert-source-path 'define-compiler-macro))
1140 (fun (ir1-convert-lambda def
1141 :debug-name (debug-namify
1142 "DEFINE-COMPILER-MACRO ~S"
1144 (setf (functional-arg-documentation fun) (eval lambda-list))
1146 (ir1-convert start cont `(%%define-compiler-macro ',name ,fun ,doc)))
1148 (when sb!xc:*compile-print*
1149 (compiler-mumble "~&; converted ~S~%" name))))