1 ;;;; This file contains miscellaneous utilities used for manipulating
2 ;;;; the IR1 representation.
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.
17 ;;; Return the innermost cleanup enclosing NODE, or NIL if there is
18 ;;; none in its function. If NODE has no cleanup, but is in a LET,
19 ;;; then we must still check the environment that the call is in.
20 (defun node-enclosing-cleanup (node)
21 (declare (type node node))
22 (do ((lexenv (node-lexenv node)
23 (lambda-call-lexenv (lexenv-lambda lexenv))))
25 (let ((cup (lexenv-cleanup lexenv)))
26 (when cup (return cup)))))
28 ;;; Convert the FORM in a block inserted between BLOCK1 and BLOCK2 as
29 ;;; an implicit MV-PROG1. The inserted block is returned. NODE is used
30 ;;; for IR1 context when converting the form. Note that the block is
31 ;;; not assigned a number, and is linked into the DFO at the
32 ;;; beginning. We indicate that we have trashed the DFO by setting
33 ;;; COMPONENT-REANALYZE. If CLEANUP is supplied, then convert with
35 (defun insert-cleanup-code (block1 block2 node form &optional cleanup)
36 (declare (type cblock block1 block2) (type node node)
37 (type (or cleanup null) cleanup))
38 (setf (component-reanalyze (block-component block1)) t)
39 (with-ir1-environment-from-node node
40 (with-component-last-block (*current-component*
41 (block-next (component-head *current-component*)))
42 (let* ((start (make-ctran))
43 (block (ctran-starts-block start))
46 (make-lexenv :cleanup cleanup)
48 (change-block-successor block1 block2 block)
49 (link-blocks block block2)
50 (ir1-convert start next nil form)
51 (setf (block-last block) (ctran-use next))
52 (setf (node-next (block-last block)) nil)
57 ;;; Return a list of all the nodes which use LVAR.
58 (declaim (ftype (sfunction (lvar) list) find-uses))
59 (defun find-uses (lvar)
60 (let ((uses (lvar-uses lvar)))
65 (declaim (ftype (sfunction (lvar) lvar) principal-lvar))
66 (defun principal-lvar (lvar)
68 (let ((use (lvar-uses lvar)))
74 (defun principal-lvar-use (lvar)
76 (declare (type lvar lvar))
77 (let ((use (lvar-uses lvar)))
79 (plu (cast-value use))
83 (defun principal-lvar-dest (lvar)
85 (declare (type lvar lvar))
86 (let ((dest (lvar-dest lvar)))
88 (pld (cast-lvar dest))
92 ;;; Update lvar use information so that NODE is no longer a use of its
95 ;;; Note: if you call this function, you may have to do a
96 ;;; REOPTIMIZE-LVAR to inform IR1 optimization that something has
98 (declaim (ftype (sfunction (node) (values))
101 ;;; Just delete NODE from its LVAR uses; LVAR is preserved so it may
102 ;;; be given a new use.
103 (defun %delete-lvar-use (node)
104 (let ((lvar (node-lvar node)))
106 (if (listp (lvar-uses lvar))
107 (let ((new-uses (delq node (lvar-uses lvar))))
108 (setf (lvar-uses lvar)
109 (if (singleton-p new-uses)
112 (setf (lvar-uses lvar) nil))
113 (setf (node-lvar node) nil)))
115 ;;; Delete NODE from its LVAR uses; if LVAR has no other uses, delete
116 ;;; its DEST's block, which must be unreachable.
117 (defun delete-lvar-use (node)
118 (let ((lvar (node-lvar node)))
120 (%delete-lvar-use node)
121 (if (null (lvar-uses lvar))
122 (binding* ((dest (lvar-dest lvar) :exit-if-null)
123 (() (not (node-deleted dest)) :exit-if-null)
124 (block (node-block dest)))
125 (mark-for-deletion block))
126 (reoptimize-lvar lvar))))
129 ;;; Update lvar use information so that NODE uses LVAR.
131 ;;; Note: if you call this function, you may have to do a
132 ;;; REOPTIMIZE-LVAR to inform IR1 optimization that something has
134 (declaim (ftype (sfunction (node (or lvar null)) (values)) add-lvar-use))
135 (defun add-lvar-use (node lvar)
136 (aver (not (node-lvar node)))
138 (let ((uses (lvar-uses lvar)))
139 (setf (lvar-uses lvar)
146 (setf (node-lvar node) lvar)))
150 ;;; Return true if LVAR destination is executed immediately after
151 ;;; NODE. Cleanups are ignored.
152 (defun immediately-used-p (lvar node)
153 (declare (type lvar lvar) (type node node))
154 (aver (eq (node-lvar node) lvar))
155 (let ((dest (lvar-dest lvar)))
156 (acond ((node-next node)
157 (eq (ctran-next it) dest))
158 (t (eq (block-start (first (block-succ (node-block node))))
159 (node-prev dest))))))
161 ;;; Returns the defined (usually untrusted) type of the combination,
162 ;;; or NIL if we couldn't figure it out.
163 (defun combination-defined-type (combination)
164 (let ((use (principal-lvar-use (basic-combination-fun combination))))
165 (or (when (ref-p use)
166 (let ((type (leaf-defined-type (ref-leaf use))))
167 (when (fun-type-p type)
168 (fun-type-returns type))))
171 ;;; Return true if LVAR destination is executed after node with only
172 ;;; uninteresting nodes intervening.
174 ;;; Uninteresting nodes are nodes in the same block which are either
175 ;;; REFs, external CASTs to the same destination, or known combinations
176 ;;; that never unwind.
177 (defun almost-immediately-used-p (lvar node)
178 (declare (type lvar lvar)
180 (aver (eq (node-lvar node) lvar))
181 (let ((dest (lvar-dest lvar)))
184 (let ((ctran (node-next node)))
186 (setf node (ctran-next ctran))
188 (return-from almost-immediately-used-p t)
193 (when (and (eq :external (cast-type-check node))
194 (eq dest (node-dest node)))
197 ;; KLUDGE: Unfortunately we don't have an attribute for
198 ;; "never unwinds", so we just special case
199 ;; %ALLOCATE-CLOSURES: it is easy to run into with eg.
200 ;; FORMAT and a non-constant first argument.
201 (when (eq '%allocate-closures (combination-fun-source-name node nil))
204 (when (eq (block-start (first (block-succ (node-block node))))
206 (return-from almost-immediately-used-p t))))))))
208 ;;;; lvar substitution
210 ;;; In OLD's DEST, replace OLD with NEW. NEW's DEST must initially be
211 ;;; NIL. We do not flush OLD's DEST.
212 (defun substitute-lvar (new old)
213 (declare (type lvar old new))
214 (aver (not (lvar-dest new)))
215 (let ((dest (lvar-dest old)))
218 (cif (setf (if-test dest) new))
219 (cset (setf (set-value dest) new))
220 (creturn (setf (return-result dest) new))
221 (exit (setf (exit-value dest) new))
223 (if (eq old (basic-combination-fun dest))
224 (setf (basic-combination-fun dest) new)
225 (setf (basic-combination-args dest)
226 (nsubst new old (basic-combination-args dest)))))
227 (cast (setf (cast-value dest) new)))
229 (setf (lvar-dest old) nil)
230 (setf (lvar-dest new) dest)
231 (flush-lvar-externally-checkable-type new))
234 ;;; Replace all uses of OLD with uses of NEW, where NEW has an
235 ;;; arbitary number of uses. NEW is supposed to be "later" than OLD.
236 (defun substitute-lvar-uses (new old propagate-dx)
237 (declare (type lvar old)
238 (type (or lvar null) new)
239 (type boolean propagate-dx))
243 (%delete-lvar-use node)
244 (add-lvar-use node new))
245 (reoptimize-lvar new)
246 (awhen (and propagate-dx (lvar-dynamic-extent old))
247 (setf (lvar-dynamic-extent old) nil)
248 (unless (lvar-dynamic-extent new)
249 (setf (lvar-dynamic-extent new) it)
250 (setf (cleanup-info it) (subst new old (cleanup-info it)))))
251 (when (lvar-dynamic-extent new)
253 (node-ends-block node))))
254 (t (flush-dest old)))
258 ;;;; block starting/creation
260 ;;; Return the block that CTRAN is the start of, making a block if
261 ;;; necessary. This function is called by IR1 translators which may
262 ;;; cause a CTRAN to be used more than once. Every CTRAN which may be
263 ;;; used more than once must start a block by the time that anyone
264 ;;; does a USE-CTRAN on it.
266 ;;; We also throw the block into the next/prev list for the
267 ;;; *CURRENT-COMPONENT* so that we keep track of which blocks we have
269 (defun ctran-starts-block (ctran)
270 (declare (type ctran ctran))
271 (ecase (ctran-kind ctran)
273 (aver (not (ctran-block ctran)))
274 (let* ((next (component-last-block *current-component*))
275 (prev (block-prev next))
276 (new-block (make-block ctran)))
277 (setf (block-next new-block) next
278 (block-prev new-block) prev
279 (block-prev next) new-block
280 (block-next prev) new-block
281 (ctran-block ctran) new-block
282 (ctran-kind ctran) :block-start)
283 (aver (not (ctran-use ctran)))
286 (ctran-block ctran))))
288 ;;; Ensure that CTRAN is the start of a block so that the use set can
289 ;;; be freely manipulated.
290 (defun ensure-block-start (ctran)
291 (declare (type ctran ctran))
292 (let ((kind (ctran-kind ctran)))
296 (setf (ctran-block ctran)
297 (make-block-key :start ctran))
298 (setf (ctran-kind ctran) :block-start))
300 (node-ends-block (ctran-use ctran)))))
303 ;;; CTRAN must be the last ctran in an incomplete block; finish the
304 ;;; block and start a new one if necessary.
305 (defun start-block (ctran)
306 (declare (type ctran ctran))
307 (aver (not (ctran-next ctran)))
308 (ecase (ctran-kind ctran)
310 (let ((block (ctran-block ctran))
311 (node (ctran-use ctran)))
312 (aver (not (block-last block)))
314 (setf (block-last block) node)
315 (setf (node-next node) nil)
316 (setf (ctran-use ctran) nil)
317 (setf (ctran-kind ctran) :unused)
318 (setf (ctran-block ctran) nil)
319 (link-blocks block (ctran-starts-block ctran))))
324 ;;; Filter values of LVAR through FORM, which must be an ordinary/mv
325 ;;; call. First argument must be 'DUMMY, which will be replaced with
326 ;;; LVAR. In case of an ordinary call the function should not have
327 ;;; return type NIL. We create a new "filtered" lvar.
329 ;;; TODO: remove preconditions.
330 (defun filter-lvar (lvar form)
331 (declare (type lvar lvar) (type list form))
332 (let* ((dest (lvar-dest lvar))
333 (ctran (node-prev dest)))
334 (with-ir1-environment-from-node dest
336 (ensure-block-start ctran)
337 (let* ((old-block (ctran-block ctran))
338 (new-start (make-ctran))
339 (filtered-lvar (make-lvar))
340 (new-block (ctran-starts-block new-start)))
342 ;; Splice in the new block before DEST, giving the new block
343 ;; all of DEST's predecessors.
344 (dolist (block (block-pred old-block))
345 (change-block-successor block old-block new-block))
347 (ir1-convert new-start ctran filtered-lvar form)
349 ;; KLUDGE: Comments at the head of this function in CMU CL
350 ;; said that somewhere in here we
351 ;; Set the new block's start and end cleanups to the *start*
352 ;; cleanup of PREV's block. This overrides the incorrect
353 ;; default from WITH-IR1-ENVIRONMENT-FROM-NODE.
354 ;; Unfortunately I can't find any code which corresponds to this.
355 ;; Perhaps it was a stale comment? Or perhaps I just don't
356 ;; understand.. -- WHN 19990521
358 ;; Replace 'DUMMY with the LVAR. (We can find 'DUMMY because
359 ;; no LET conversion has been done yet.) The [mv-]combination
360 ;; code from the call in the form will be the use of the new
361 ;; check lvar. We substitute for the first argument of
363 (let* ((node (lvar-use filtered-lvar))
364 (args (basic-combination-args node))
365 (victim (principal-lvar (first args))))
366 (aver (eq (constant-value (ref-leaf (lvar-use victim)))
369 (substitute-lvar filtered-lvar lvar)
370 (substitute-lvar lvar victim)
373 ;; Invoking local call analysis converts this call to a LET.
374 (locall-analyze-component *current-component*))))
377 ;;; Delete NODE and VALUE. It may result in some calls becoming tail.
378 (defun delete-filter (node lvar value)
379 (aver (eq (lvar-dest value) node))
380 (aver (eq (node-lvar node) lvar))
381 (cond (lvar (collect ((merges))
382 (when (return-p (lvar-dest lvar))
384 (when (and (basic-combination-p use)
385 (eq (basic-combination-kind use) :local))
387 (substitute-lvar-uses lvar value
388 (and lvar (eq (lvar-uses lvar) node)))
389 (%delete-lvar-use node)
392 (dolist (merge (merges))
393 (merge-tail-sets merge)))))
394 (t (flush-dest value)
395 (unlink-node node))))
397 ;;; Make a CAST and insert it into IR1 before node NEXT.
398 (defun insert-cast-before (next lvar type policy)
399 (declare (type node next) (type lvar lvar) (type ctype type))
400 (with-ir1-environment-from-node next
401 (let* ((ctran (node-prev next))
402 (cast (make-cast lvar type policy))
403 (internal-ctran (make-ctran)))
404 (setf (ctran-next ctran) cast
405 (node-prev cast) ctran)
406 (use-ctran cast internal-ctran)
407 (link-node-to-previous-ctran next internal-ctran)
408 (setf (lvar-dest lvar) cast)
409 (reoptimize-lvar lvar)
410 (when (return-p next)
411 (node-ends-block cast))
412 (setf (block-attributep (block-flags (node-block cast))
413 type-check type-asserted)
417 ;;;; miscellaneous shorthand functions
419 ;;; Return the home (i.e. enclosing non-LET) CLAMBDA for NODE. Since
420 ;;; the LEXENV-LAMBDA may be deleted, we must chain up the
421 ;;; LAMBDA-CALL-LEXENV thread until we find a CLAMBDA that isn't
422 ;;; deleted, and then return its home.
423 (defun node-home-lambda (node)
424 (declare (type node node))
425 (do ((fun (lexenv-lambda (node-lexenv node))
426 (lexenv-lambda (lambda-call-lexenv fun))))
427 ((not (memq (functional-kind fun) '(:deleted :zombie)))
429 (when (eq (lambda-home fun) fun)
432 #!-sb-fluid (declaim (inline node-block))
433 (defun node-block (node)
434 (ctran-block (node-prev node)))
435 (declaim (ftype (sfunction (node) component) node-component))
436 (defun node-component (node)
437 (block-component (node-block node)))
438 (declaim (ftype (sfunction (node) physenv) node-physenv))
439 (defun node-physenv (node)
440 (lambda-physenv (node-home-lambda node)))
441 #!-sb-fluid (declaim (inline node-dest))
442 (defun node-dest (node)
443 (awhen (node-lvar node) (lvar-dest it)))
445 #!-sb-fluid (declaim (inline node-stack-allocate-p))
446 (defun node-stack-allocate-p (node)
447 (awhen (node-lvar node)
448 (lvar-dynamic-extent it)))
450 (defun flushable-combination-p (call)
451 (declare (type combination call))
452 (let ((kind (combination-kind call))
453 (info (combination-fun-info call)))
454 (when (and (eq kind :known) (fun-info-p info))
455 (let ((attr (fun-info-attributes info)))
456 (when (and (not (ir1-attributep attr call))
457 ;; FIXME: For now, don't consider potentially flushable
458 ;; calls flushable when they have the CALL attribute.
459 ;; Someday we should look at the functional args to
460 ;; determine if they have any side effects.
461 (if (policy call (= safety 3))
462 (ir1-attributep attr flushable)
463 (ir1-attributep attr unsafely-flushable)))
466 ;;;; DYNAMIC-EXTENT related
468 (defun lambda-var-original-name (leaf)
469 (let ((home (lambda-var-home leaf)))
470 (if (eq :external (functional-kind home))
471 (let* ((entry (functional-entry-fun home))
472 (p (1- (position leaf (lambda-vars home)))))
474 (if (optional-dispatch-p entry)
475 (elt (optional-dispatch-arglist entry) p)
476 (elt (lambda-vars entry) p))))
477 (leaf-debug-name leaf))))
479 (defun note-no-stack-allocation (lvar &key flush)
480 (do-uses (use (principal-lvar lvar))
482 ;; Don't complain about not being able to stack allocate constants.
483 (and (ref-p use) (constant-p (ref-leaf use)))
484 ;; If we're flushing, don't complain if we can flush the combination.
485 (and flush (combination-p use) (flushable-combination-p use))
486 ;; Don't report those with homes in :OPTIONAL -- we'd get doubled
488 (and (ref-p use) (lambda-var-p (ref-leaf use))
489 (eq :optional (lambda-kind (lambda-var-home (ref-leaf use))))))
490 ;; FIXME: For the first leg (lambda-bind (lambda-var-home ...))
491 ;; would be a far better description, but since we use
492 ;; *COMPILER-ERROR-CONTEXT* for muffling we can't -- as that node
493 ;; can have different handled conditions.
494 (let ((*compiler-error-context* use))
495 (if (and (ref-p use) (lambda-var-p (ref-leaf use)))
496 (compiler-notify "~@<could~2:I not stack allocate ~S in: ~S~:@>"
497 (lambda-var-original-name (ref-leaf use))
498 (find-original-source (node-source-path use)))
499 (compiler-notify "~@<could~2:I not stack allocate: ~S~:@>"
500 (find-original-source (node-source-path use))))))))
502 (defun use-good-for-dx-p (use dx &optional component)
503 ;; FIXME: Can casts point to LVARs in other components?
504 ;; RECHECK-DYNAMIC-EXTENT-LVARS assumes that they can't -- that is, that the
505 ;; PRINCIPAL-LVAR is always in the same component as the original one. It
506 ;; would be either good to have an explanation of why casts don't point
507 ;; across components, or an explanation of when they do it. ...in the
508 ;; meanwhile AVER that our assumption holds true.
509 (aver (or (not component) (eq component (node-component use))))
510 (or (dx-combination-p use dx)
512 (not (cast-type-check use))
513 (lvar-good-for-dx-p (cast-value use) dx component))
514 (and (trivial-lambda-var-ref-p use)
515 (let ((uses (lvar-uses (trivial-lambda-var-ref-lvar use))))
517 (lvar-good-for-dx-p (trivial-lambda-var-ref-lvar use) dx component))))))
519 (defun lvar-good-for-dx-p (lvar dx &optional component)
520 (let ((uses (lvar-uses lvar)))
524 (use-good-for-dx-p use dx component))
526 (use-good-for-dx-p uses dx component))))
528 (defun known-dx-combination-p (use dx)
529 (and (eq (combination-kind use) :known)
530 (let ((info (combination-fun-info use)))
531 (or (awhen (fun-info-stack-allocate-result info)
533 (awhen (fun-info-result-arg info)
534 (let ((args (combination-args use)))
535 (lvar-good-for-dx-p (if (zerop it)
540 (defun dx-combination-p (use dx)
541 (and (combination-p use)
543 ;; Known, and can do DX.
544 (known-dx-combination-p use dx)
545 ;; Possibly a not-yet-eliminated lambda which ends up returning the
546 ;; results of an actual known DX combination.
547 (let* ((fun (combination-fun use))
548 (ref (principal-lvar-use fun))
549 (clambda (when (ref-p ref)
551 (creturn (when (lambda-p clambda)
552 (lambda-return clambda)))
553 (result-use (when (return-p creturn)
554 (principal-lvar-use (return-result creturn)))))
555 ;; FIXME: We should be able to deal with multiple uses here as well.
556 (and (dx-combination-p result-use dx)
557 (combination-args-flow-cleanly-p use result-use dx))))))
559 (defun combination-args-flow-cleanly-p (combination1 combination2 dx)
560 (labels ((recurse (combination)
561 (or (eq combination combination2)
562 (if (known-dx-combination-p combination dx)
563 (let ((dest (lvar-dest (combination-lvar combination))))
564 (and (combination-p dest)
566 (let* ((fun1 (combination-fun combination))
567 (ref1 (principal-lvar-use fun1))
568 (clambda1 (when (ref-p ref1) (ref-leaf ref1))))
569 (when (lambda-p clambda1)
570 (dolist (var (lambda-vars clambda1) t)
571 (dolist (var-ref (lambda-var-refs var))
572 (let ((dest (principal-lvar-dest (ref-lvar var-ref))))
573 (unless (and (combination-p dest) (recurse dest))
574 (return-from combination-args-flow-cleanly-p nil)))))))))))
575 (recurse combination1)))
577 (defun ref-good-for-dx-p (ref)
578 (let* ((lvar (ref-lvar ref))
579 (dest (when lvar (lvar-dest lvar))))
580 (and (combination-p dest)
581 (eq :known (combination-kind dest))
582 (awhen (combination-fun-info dest)
583 (or (ir1-attributep (fun-info-attributes it) dx-safe)
584 (and (not (combination-lvar dest))
585 (awhen (fun-info-result-arg it)
586 (eql lvar (nth it (combination-args dest))))))))))
588 (defun trivial-lambda-var-ref-p (use)
590 (let ((var (ref-leaf use)))
591 ;; lambda-var, no SETS, not explicitly indefinite-extent.
592 (when (and (lambda-var-p var) (not (lambda-var-sets var))
593 (neq :indefinite (lambda-var-extent var)))
594 (let ((home (lambda-var-home var))
595 (refs (lambda-var-refs var)))
596 ;; bound by a non-XEP system lambda, no other REFS that aren't
597 ;; DX-SAFE, or are result-args when the result is discarded.
598 (when (and (lambda-system-lambda-p home)
599 (neq :external (lambda-kind home))
601 (unless (or (eq use ref) (ref-good-for-dx-p ref))
603 ;; the LAMBDA this var is bound by has only a single REF, going
605 (let* ((lambda-refs (lambda-refs home))
606 (primary (car lambda-refs)))
608 (not (cdr lambda-refs))
609 (combination-p (lvar-dest (ref-lvar primary)))))))))))
611 (defun trivial-lambda-var-ref-lvar (use)
612 (let* ((this (ref-leaf use))
613 (fun (lambda-var-home this))
614 (vars (lambda-vars fun))
615 (combination (lvar-dest (ref-lvar (car (lambda-refs fun)))))
616 (args (combination-args combination)))
617 (aver (= (length vars) (length args)))
618 (loop for var in vars
623 ;;; This needs to play nice with LVAR-GOOD-FOR-DX-P and friends.
624 (defun handle-nested-dynamic-extent-lvars (dx lvar &optional recheck-component)
625 (let ((uses (lvar-uses lvar)))
626 ;; DX value generators must end their blocks: see UPDATE-UVL-LIVE-SETS.
627 ;; Uses of mupltiple-use LVARs already end their blocks, so we just need
628 ;; to process uses of single-use LVARs.
630 (node-ends-block uses))
631 ;; If this LVAR's USE is good for DX, it is either a CAST, or it
632 ;; must be a regular combination whose arguments are potentially DX as well.
633 (flet ((recurse (use)
636 (handle-nested-dynamic-extent-lvars
637 dx (cast-value use) recheck-component))
639 (loop for arg in (combination-args use)
640 ;; deleted args show up as NIL here
642 (lvar-good-for-dx-p arg dx recheck-component))
643 append (handle-nested-dynamic-extent-lvars
644 dx arg recheck-component)))
646 (let* ((other (trivial-lambda-var-ref-lvar use)))
647 (unless (eq other lvar)
648 (handle-nested-dynamic-extent-lvars
649 dx other recheck-component)))))))
652 (loop for use in uses
653 when (use-good-for-dx-p use dx recheck-component)
655 (when (use-good-for-dx-p uses dx recheck-component)
660 (declaim (inline block-to-be-deleted-p))
661 (defun block-to-be-deleted-p (block)
662 (or (block-delete-p block)
663 (eq (functional-kind (block-home-lambda block)) :deleted)))
665 ;;; Checks whether NODE is in a block to be deleted
666 (declaim (inline node-to-be-deleted-p))
667 (defun node-to-be-deleted-p (node)
668 (block-to-be-deleted-p (node-block node)))
670 (declaim (ftype (sfunction (clambda) cblock) lambda-block))
671 (defun lambda-block (clambda)
672 (node-block (lambda-bind clambda)))
673 (declaim (ftype (sfunction (clambda) component) lambda-component))
674 (defun lambda-component (clambda)
675 (block-component (lambda-block clambda)))
677 (declaim (ftype (sfunction (cblock) node) block-start-node))
678 (defun block-start-node (block)
679 (ctran-next (block-start block)))
681 ;;; Return the enclosing cleanup for environment of the first or last
683 (defun block-start-cleanup (block)
684 (node-enclosing-cleanup (block-start-node block)))
685 (defun block-end-cleanup (block)
686 (node-enclosing-cleanup (block-last block)))
688 ;;; Return the non-LET LAMBDA that holds BLOCK's code, or NIL
689 ;;; if there is none.
691 ;;; There can legitimately be no home lambda in dead code early in the
692 ;;; IR1 conversion process, e.g. when IR1-converting the SETQ form in
693 ;;; (BLOCK B (RETURN-FROM B) (SETQ X 3))
694 ;;; where the block is just a placeholder during parsing and doesn't
695 ;;; actually correspond to code which will be written anywhere.
696 (declaim (ftype (sfunction (cblock) (or clambda null)) block-home-lambda-or-null))
697 (defun block-home-lambda-or-null (block)
698 (if (node-p (block-last block))
699 ;; This is the old CMU CL way of doing it.
700 (node-home-lambda (block-last block))
701 ;; Now that SBCL uses this operation more aggressively than CMU
702 ;; CL did, the old CMU CL way of doing it can fail in two ways.
703 ;; 1. It can fail in a few cases even when a meaningful home
704 ;; lambda exists, e.g. in IR1-CONVERT of one of the legs of
706 ;; 2. It can fail when converting a form which is born orphaned
707 ;; so that it never had a meaningful home lambda, e.g. a form
708 ;; which follows a RETURN-FROM or GO form.
709 (let ((pred-list (block-pred block)))
710 ;; To deal with case 1, we reason that
711 ;; previous-in-target-execution-order blocks should be in the
712 ;; same lambda, and that they seem in practice to be
713 ;; previous-in-compilation-order blocks too, so we look back
714 ;; to find one which is sufficiently initialized to tell us
715 ;; what the home lambda is.
717 ;; We could get fancy about this, flooding through the
718 ;; graph of all the previous blocks, but in practice it
719 ;; seems to work just to grab the first previous block and
721 (node-home-lambda (block-last (first pred-list)))
722 ;; In case 2, we end up with an empty PRED-LIST and
723 ;; have to punt: There's no home lambda.
726 ;;; Return the non-LET LAMBDA that holds BLOCK's code.
727 (declaim (ftype (sfunction (cblock) clambda) block-home-lambda))
728 (defun block-home-lambda (block)
729 (block-home-lambda-or-null block))
731 ;;; Return the IR1 physical environment for BLOCK.
732 (declaim (ftype (sfunction (cblock) physenv) block-physenv))
733 (defun block-physenv (block)
734 (lambda-physenv (block-home-lambda block)))
736 ;;; Return the Top Level Form number of PATH, i.e. the ordinal number
737 ;;; of its original source's top level form in its compilation unit.
738 (defun source-path-tlf-number (path)
739 (declare (list path))
742 ;;; Return the (reversed) list for the PATH in the original source
743 ;;; (with the Top Level Form number last).
744 (defun source-path-original-source (path)
745 (declare (list path) (inline member))
746 (cddr (member 'original-source-start path :test #'eq)))
748 ;;; Return the Form Number of PATH's original source inside the Top
749 ;;; Level Form that contains it. This is determined by the order that
750 ;;; we walk the subforms of the top level source form.
751 (defun source-path-form-number (path)
752 (declare (list path) (inline member))
753 (cadr (member 'original-source-start path :test #'eq)))
755 ;;; Return a list of all the enclosing forms not in the original
756 ;;; source that converted to get to this form, with the immediate
757 ;;; source for node at the start of the list.
758 (defun source-path-forms (path)
759 (subseq path 0 (position 'original-source-start path)))
761 (defun tree-some (predicate tree)
762 (let ((seen (make-hash-table)))
763 (labels ((walk (tree)
764 (cond ((funcall predicate tree))
766 (not (gethash tree seen)))
767 (setf (gethash tree seen) t)
768 (or (walk (car tree))
769 (walk (cdr tree)))))))
772 ;;; Return the innermost source form for NODE.
773 (defun node-source-form (node)
774 (declare (type node node))
775 (let* ((path (node-source-path node))
776 (forms (remove-if (lambda (x)
777 (tree-some #'leaf-p x))
778 (source-path-forms path))))
779 ;; another option: if first form includes a leaf, return
780 ;; find-original-source instead.
783 (values (find-original-source path)))))
785 ;;; Return NODE-SOURCE-FORM, T if lvar has a single use, otherwise
787 (defun lvar-source (lvar)
788 (let ((use (lvar-uses lvar)))
791 (values (node-source-form use) t))))
793 ;;; Return the unique node, delivering a value to LVAR.
794 #!-sb-fluid (declaim (inline lvar-use))
795 (defun lvar-use (lvar)
796 (the (not list) (lvar-uses lvar)))
798 #!-sb-fluid (declaim (inline lvar-has-single-use-p))
799 (defun lvar-has-single-use-p (lvar)
800 (typep (lvar-uses lvar) '(not list)))
802 ;;; Return the LAMBDA that is CTRAN's home, or NIL if there is none.
803 (declaim (ftype (sfunction (ctran) (or clambda null))
804 ctran-home-lambda-or-null))
805 (defun ctran-home-lambda-or-null (ctran)
806 ;; KLUDGE: This function is a post-CMU-CL hack by WHN, and this
807 ;; implementation might not be quite right, or might be uglier than
808 ;; necessary. It appears that the original Python never found a need
809 ;; to do this operation. The obvious things based on
810 ;; NODE-HOME-LAMBDA of CTRAN-USE usually work; then if that fails,
811 ;; BLOCK-HOME-LAMBDA of CTRAN-BLOCK works, given that we
812 ;; generalize it enough to grovel harder when the simple CMU CL
813 ;; approach fails, and furthermore realize that in some exceptional
814 ;; cases it might return NIL. -- WHN 2001-12-04
815 (cond ((ctran-use ctran)
816 (node-home-lambda (ctran-use ctran)))
818 (block-home-lambda-or-null (ctran-block ctran)))
820 (bug "confused about home lambda for ~S" ctran))))
822 ;;; Return the LAMBDA that is CTRAN's home.
823 (declaim (ftype (sfunction (ctran) clambda) ctran-home-lambda))
824 (defun ctran-home-lambda (ctran)
825 (ctran-home-lambda-or-null ctran))
827 (declaim (inline cast-single-value-p))
828 (defun cast-single-value-p (cast)
829 (not (values-type-p (cast-asserted-type cast))))
831 #!-sb-fluid (declaim (inline lvar-single-value-p))
832 (defun lvar-single-value-p (lvar)
834 (let ((dest (lvar-dest lvar)))
839 (eq (basic-combination-fun dest) lvar))
842 (declare (notinline lvar-single-value-p))
843 (and (cast-single-value-p dest)
844 (lvar-single-value-p (node-lvar dest)))))
848 (defun principal-lvar-end (lvar)
849 (loop for prev = lvar then (node-lvar dest)
850 for dest = (and prev (lvar-dest prev))
852 finally (return (values dest prev))))
854 (defun principal-lvar-single-valuify (lvar)
855 (loop for prev = lvar then (node-lvar dest)
856 for dest = (and prev (lvar-dest prev))
858 do (setf (node-derived-type dest)
859 (make-short-values-type (list (single-value-type
860 (node-derived-type dest)))))
861 (reoptimize-lvar prev)))
863 ;;; Return a new LEXENV just like DEFAULT except for the specified
864 ;;; slot values. Values for the alist slots are APPENDed to the
865 ;;; beginning of the current value, rather than replacing it entirely.
866 (defun make-lexenv (&key (default *lexenv*)
867 funs vars blocks tags
869 (lambda (lexenv-lambda default))
870 (cleanup (lexenv-cleanup default))
871 (handled-conditions (lexenv-handled-conditions default))
872 (disabled-package-locks
873 (lexenv-disabled-package-locks default))
874 (policy (lexenv-policy default))
875 (user-data (lexenv-user-data default)))
876 (macrolet ((frob (var slot)
877 `(let ((old (,slot default)))
881 (internal-make-lexenv
882 (frob funs lexenv-funs)
883 (frob vars lexenv-vars)
884 (frob blocks lexenv-blocks)
885 (frob tags lexenv-tags)
886 (frob type-restrictions lexenv-type-restrictions)
888 cleanup handled-conditions disabled-package-locks
892 ;;; Makes a LEXENV, suitable for using in a MACROLET introduced
894 (defun make-restricted-lexenv (lexenv)
895 (flet ((fun-good-p (fun)
896 (destructuring-bind (name . thing) fun
897 (declare (ignore name))
901 (cons (aver (eq (car thing) 'macro))
904 (destructuring-bind (name . thing) var
905 (declare (ignore name))
907 ;; The evaluator will mark lexicals with :BOGUS when it
908 ;; translates an interpreter lexenv to a compiler
910 ((or leaf #!+sb-eval (member :bogus)) nil)
911 (cons (aver (eq (car thing) 'macro))
913 (heap-alien-info nil)))))
914 (internal-make-lexenv
915 (remove-if-not #'fun-good-p (lexenv-funs lexenv))
916 (remove-if-not #'var-good-p (lexenv-vars lexenv))
919 (lexenv-type-restrictions lexenv) ; XXX
922 (lexenv-handled-conditions lexenv)
923 (lexenv-disabled-package-locks lexenv)
924 (lexenv-policy lexenv)
925 (lexenv-user-data lexenv))))
927 ;;;; flow/DFO/component hackery
929 ;;; Join BLOCK1 and BLOCK2.
930 (defun link-blocks (block1 block2)
931 (declare (type cblock block1 block2))
932 (setf (block-succ block1)
933 (if (block-succ block1)
934 (%link-blocks block1 block2)
936 (push block1 (block-pred block2))
938 (defun %link-blocks (block1 block2)
939 (declare (type cblock block1 block2))
940 (let ((succ1 (block-succ block1)))
941 (aver (not (memq block2 succ1)))
942 (cons block2 succ1)))
944 ;;; This is like LINK-BLOCKS, but we separate BLOCK1 and BLOCK2. If
945 ;;; this leaves a successor with a single predecessor that ends in an
946 ;;; IF, then set BLOCK-TEST-MODIFIED so that any test constraint will
947 ;;; now be able to be propagated to the successor.
948 (defun unlink-blocks (block1 block2)
949 (declare (type cblock block1 block2))
950 (let ((succ1 (block-succ block1)))
951 (if (eq block2 (car succ1))
952 (setf (block-succ block1) (cdr succ1))
953 (do ((succ (cdr succ1) (cdr succ))
955 ((eq (car succ) block2)
956 (setf (cdr prev) (cdr succ)))
959 (let ((new-pred (delq block1 (block-pred block2))))
960 (setf (block-pred block2) new-pred)
961 (when (singleton-p new-pred)
962 (let ((pred-block (first new-pred)))
963 (when (if-p (block-last pred-block))
964 (setf (block-test-modified pred-block) t)))))
967 ;;; Swing the succ/pred link between BLOCK and OLD to be between BLOCK
968 ;;; and NEW. If BLOCK ends in an IF, then we have to fix up the
969 ;;; consequent/alternative blocks to point to NEW. We also set
970 ;;; BLOCK-TEST-MODIFIED so that any test constraint will be applied to
971 ;;; the new successor.
972 (defun change-block-successor (block old new)
973 (declare (type cblock new old block))
974 (unlink-blocks block old)
975 (let ((last (block-last block))
976 (comp (block-component block)))
977 (setf (component-reanalyze comp) t)
980 (setf (block-test-modified block) t)
981 (let* ((succ-left (block-succ block))
982 (new (if (and (eq new (component-tail comp))
986 (unless (memq new succ-left)
987 (link-blocks block new))
988 (macrolet ((frob (slot)
989 `(when (eq (,slot last) old)
990 (setf (,slot last) new))))
992 (frob if-alternative)
993 (when (eq (if-consequent last)
994 (if-alternative last))
995 (reoptimize-component (block-component block) :maybe)))))
997 (unless (memq new (block-succ block))
998 (link-blocks block new)))))
1002 ;;; Unlink a block from the next/prev chain. We also null out the
1004 (declaim (ftype (sfunction (cblock) (values)) remove-from-dfo))
1005 (defun remove-from-dfo (block)
1006 (let ((next (block-next block))
1007 (prev (block-prev block)))
1008 (setf (block-component block) nil)
1009 (setf (block-next prev) next)
1010 (setf (block-prev next) prev))
1013 ;;; Add BLOCK to the next/prev chain following AFTER. We also set the
1014 ;;; COMPONENT to be the same as for AFTER.
1015 (defun add-to-dfo (block after)
1016 (declare (type cblock block after))
1017 (let ((next (block-next after))
1018 (comp (block-component after)))
1019 (aver (not (eq (component-kind comp) :deleted)))
1020 (setf (block-component block) comp)
1021 (setf (block-next after) block)
1022 (setf (block-prev block) after)
1023 (setf (block-next block) next)
1024 (setf (block-prev next) block))
1027 ;;; List all NLX-INFOs which BLOCK can exit to.
1029 ;;; We hope that no cleanup actions are performed in the middle of
1030 ;;; BLOCK, so it is enough to look only at cleanups in the block
1031 ;;; end. The tricky thing is a special cleanup block; all its nodes
1032 ;;; have the same cleanup info, corresponding to the start, so the
1033 ;;; same approach returns safe result.
1034 (defun map-block-nlxes (fun block &optional dx-cleanup-fun)
1035 (loop for cleanup = (block-end-cleanup block)
1036 then (node-enclosing-cleanup (cleanup-mess-up cleanup))
1038 do (let ((mess-up (cleanup-mess-up cleanup)))
1039 (case (cleanup-kind cleanup)
1041 (aver (entry-p mess-up))
1042 (loop for exit in (entry-exits mess-up)
1043 for nlx-info = (exit-nlx-info exit)
1044 do (funcall fun nlx-info)))
1045 ((:catch :unwind-protect)
1046 (aver (combination-p mess-up))
1047 (let* ((arg-lvar (first (basic-combination-args mess-up)))
1048 (nlx-info (constant-value (ref-leaf (lvar-use arg-lvar)))))
1049 (funcall fun nlx-info)))
1051 (when dx-cleanup-fun
1052 (funcall dx-cleanup-fun cleanup)))))))
1054 ;;; Set the FLAG for all the blocks in COMPONENT to NIL, except for
1055 ;;; the head and tail which are set to T.
1056 (declaim (ftype (sfunction (component) (values)) clear-flags))
1057 (defun clear-flags (component)
1058 (let ((head (component-head component))
1059 (tail (component-tail component)))
1060 (setf (block-flag head) t)
1061 (setf (block-flag tail) t)
1062 (do-blocks (block component)
1063 (setf (block-flag block) nil)))
1066 ;;; Make a component with no blocks in it. The BLOCK-FLAG is initially
1067 ;;; true in the head and tail blocks.
1068 (declaim (ftype (sfunction () component) make-empty-component))
1069 (defun make-empty-component ()
1070 (let* ((head (make-block-key :start nil :component nil))
1071 (tail (make-block-key :start nil :component nil))
1072 (res (make-component head tail)))
1073 (setf (block-flag head) t)
1074 (setf (block-flag tail) t)
1075 (setf (block-component head) res)
1076 (setf (block-component tail) res)
1077 (setf (block-next head) tail)
1078 (setf (block-prev tail) head)
1081 ;;; Make NODE the LAST node in its block, splitting the block if necessary.
1082 ;;; The new block is added to the DFO immediately following NODE's block.
1083 (defun node-ends-block (node)
1084 (declare (type node node))
1085 (let* ((block (node-block node))
1086 (start (node-next node))
1087 (last (block-last block)))
1088 (check-type last node)
1089 (unless (eq last node)
1090 (aver (and (eq (ctran-kind start) :inside-block)
1091 (not (block-delete-p block))))
1092 (let* ((succ (block-succ block))
1094 (make-block-key :start start
1095 :component (block-component block)
1096 :succ succ :last last)))
1097 (setf (ctran-kind start) :block-start)
1098 (setf (ctran-use start) nil)
1099 (setf (block-last block) node)
1100 (setf (node-next node) nil)
1102 (setf (block-pred b)
1103 (cons new-block (remove block (block-pred b)))))
1104 (setf (block-succ block) ())
1105 (link-blocks block new-block)
1106 (add-to-dfo new-block block)
1107 (setf (component-reanalyze (block-component block)) t)
1109 (do ((ctran start (node-next (ctran-next ctran))))
1111 (setf (ctran-block ctran) new-block))
1113 (setf (block-type-asserted block) t)
1114 (setf (block-test-modified block) t))))
1119 ;;; Deal with deleting the last (read) reference to a LAMBDA-VAR.
1120 (defun delete-lambda-var (leaf)
1121 (declare (type lambda-var leaf))
1123 (setf (lambda-var-deleted leaf) t)
1124 ;; Iterate over all local calls flushing the corresponding argument,
1125 ;; allowing the computation of the argument to be deleted. We also
1126 ;; mark the LET for reoptimization, since it may be that we have
1127 ;; deleted its last variable.
1128 (let* ((fun (lambda-var-home leaf))
1129 (n (position leaf (lambda-vars fun))))
1130 (dolist (ref (leaf-refs fun))
1131 (let* ((lvar (node-lvar ref))
1132 (dest (and lvar (lvar-dest lvar))))
1133 (when (and (combination-p dest)
1134 (eq (basic-combination-fun dest) lvar)
1135 (eq (basic-combination-kind dest) :local))
1136 (let* ((args (basic-combination-args dest))
1138 (reoptimize-lvar arg)
1140 (setf (elt args n) nil))))))
1142 ;; The LAMBDA-VAR may still have some SETs, but this doesn't cause
1143 ;; too much difficulty, since we can efficiently implement
1144 ;; write-only variables. We iterate over the SETs, marking their
1145 ;; blocks for dead code flushing, since we can delete SETs whose
1147 (dolist (set (lambda-var-sets leaf))
1148 (setf (block-flush-p (node-block set)) t))
1152 ;;; Note that something interesting has happened to VAR.
1153 (defun reoptimize-lambda-var (var)
1154 (declare (type lambda-var var))
1155 (let ((fun (lambda-var-home var)))
1156 ;; We only deal with LET variables, marking the corresponding
1157 ;; initial value arg as needing to be reoptimized.
1158 (when (and (eq (functional-kind fun) :let)
1160 (do ((args (basic-combination-args
1161 (lvar-dest (node-lvar (first (leaf-refs fun)))))
1163 (vars (lambda-vars fun) (cdr vars)))
1164 ((eq (car vars) var)
1165 (reoptimize-lvar (car args))))))
1168 ;;; Delete a function that has no references. This need only be called
1169 ;;; on functions that never had any references, since otherwise
1170 ;;; DELETE-REF will handle the deletion.
1171 (defun delete-functional (fun)
1172 (aver (and (null (leaf-refs fun))
1173 (not (functional-entry-fun fun))))
1175 (optional-dispatch (delete-optional-dispatch fun))
1176 (clambda (delete-lambda fun)))
1179 ;;; Deal with deleting the last reference to a CLAMBDA, which means
1180 ;;; that the lambda is unreachable, so that its body may be
1181 ;;; deleted. We set FUNCTIONAL-KIND to :DELETED and rely on
1182 ;;; IR1-OPTIMIZE to delete its blocks.
1183 (defun delete-lambda (clambda)
1184 (declare (type clambda clambda))
1185 (let ((original-kind (functional-kind clambda))
1186 (bind (lambda-bind clambda)))
1187 (aver (not (member original-kind '(:deleted :toplevel))))
1188 (aver (not (functional-has-external-references-p clambda)))
1189 (aver (or (eq original-kind :zombie) bind))
1190 (setf (functional-kind clambda) :deleted)
1191 (setf (lambda-bind clambda) nil)
1193 (labels ((delete-children (lambda)
1194 (dolist (child (lambda-children lambda))
1195 (cond ((eq (functional-kind child) :deleted)
1196 (delete-children child))
1198 (delete-lambda child))))
1199 (setf (lambda-children lambda) nil)
1200 (setf (lambda-parent lambda) nil)))
1201 (delete-children clambda))
1203 ;; (The IF test is (FUNCTIONAL-SOMEWHAT-LETLIKE-P CLAMBDA), except
1204 ;; that we're using the old value of the KIND slot, not the
1205 ;; current slot value, which has now been set to :DELETED.)
1208 ((:let :mv-let :assignment)
1209 (let ((bind-block (node-block bind)))
1210 (mark-for-deletion bind-block))
1211 (let ((home (lambda-home clambda)))
1212 (setf (lambda-lets home) (delete clambda (lambda-lets home))))
1213 ;; KLUDGE: In presence of NLEs we cannot always understand that
1214 ;; LET's BIND dominates its body [for a LET "its" body is not
1215 ;; quite its]; let's delete too dangerous for IR2 stuff. --
1217 (dolist (var (lambda-vars clambda))
1218 (flet ((delete-node (node)
1219 (mark-for-deletion (node-block node))))
1220 (mapc #'delete-node (leaf-refs var))
1221 (mapc #'delete-node (lambda-var-sets var)))))
1223 ;; Function has no reachable references.
1224 (dolist (ref (lambda-refs clambda))
1225 (mark-for-deletion (node-block ref)))
1226 ;; If the function isn't a LET, we unlink the function head
1227 ;; and tail from the component head and tail to indicate that
1228 ;; the code is unreachable. We also delete the function from
1229 ;; COMPONENT-LAMBDAS (it won't be there before local call
1230 ;; analysis, but no matter.) If the lambda was never
1231 ;; referenced, we give a note.
1232 (let* ((bind-block (node-block bind))
1233 (component (block-component bind-block))
1234 (return (lambda-return clambda))
1235 (return-block (and return (node-block return))))
1236 (unless (leaf-ever-used clambda)
1237 (let ((*compiler-error-context* bind))
1238 (compiler-notify 'code-deletion-note
1239 :format-control "deleting unused function~:[.~;~:*~% ~S~]"
1240 :format-arguments (list (leaf-debug-name clambda)))))
1241 (unless (block-delete-p bind-block)
1242 (unlink-blocks (component-head component) bind-block))
1243 (when (and return-block (not (block-delete-p return-block)))
1244 (mark-for-deletion return-block)
1245 (unlink-blocks return-block (component-tail component)))
1246 (setf (component-reanalyze component) t)
1247 (let ((tails (lambda-tail-set clambda)))
1248 (setf (tail-set-funs tails)
1249 (delete clambda (tail-set-funs tails)))
1250 (setf (lambda-tail-set clambda) nil))
1251 (setf (component-lambdas component)
1252 (delq clambda (component-lambdas component))))))
1254 ;; If the lambda is an XEP, then we null out the ENTRY-FUN in its
1255 ;; ENTRY-FUN so that people will know that it is not an entry
1257 (when (eq original-kind :external)
1258 (let ((fun (functional-entry-fun clambda)))
1259 (setf (functional-entry-fun fun) nil)
1260 (when (optional-dispatch-p fun)
1261 (delete-optional-dispatch fun)))))
1265 ;;; Deal with deleting the last reference to an OPTIONAL-DISPATCH. We
1266 ;;; have to be a bit more careful than with lambdas, since DELETE-REF
1267 ;;; is used both before and after local call analysis. Afterward, all
1268 ;;; references to still-existing OPTIONAL-DISPATCHes have been moved
1269 ;;; to the XEP, leaving it with no references at all. So we look at
1270 ;;; the XEP to see whether an optional-dispatch is still really being
1271 ;;; used. But before local call analysis, there are no XEPs, and all
1272 ;;; references are direct.
1274 ;;; When we do delete the OPTIONAL-DISPATCH, we grovel all of its
1275 ;;; entry-points, making them be normal lambdas, and then deleting the
1276 ;;; ones with no references. This deletes any e-p lambdas that were
1277 ;;; either never referenced, or couldn't be deleted when the last
1278 ;;; reference was deleted (due to their :OPTIONAL kind.)
1280 ;;; Note that the last optional entry point may alias the main entry,
1281 ;;; so when we process the main entry, its KIND may have been changed
1282 ;;; to NIL or even converted to a LETlike value.
1283 (defun delete-optional-dispatch (leaf)
1284 (declare (type optional-dispatch leaf))
1285 (let ((entry (functional-entry-fun leaf)))
1286 (unless (and entry (leaf-refs entry))
1287 (aver (or (not entry) (eq (functional-kind entry) :deleted)))
1288 (setf (functional-kind leaf) :deleted)
1291 (unless (eq (functional-kind fun) :deleted)
1292 (aver (eq (functional-kind fun) :optional))
1293 (setf (functional-kind fun) nil)
1294 (let ((refs (leaf-refs fun)))
1296 (delete-lambda fun))
1298 (or (maybe-let-convert fun)
1299 (maybe-convert-to-assignment fun)))
1301 (maybe-convert-to-assignment fun)))))))
1303 (dolist (ep (optional-dispatch-entry-points leaf))
1304 (when (promise-ready-p ep)
1306 (when (optional-dispatch-more-entry leaf)
1307 (frob (optional-dispatch-more-entry leaf)))
1308 (let ((main (optional-dispatch-main-entry leaf)))
1310 (setf (functional-entry-fun entry) main)
1311 (setf (functional-entry-fun main) entry))
1312 (when (eq (functional-kind main) :optional)
1317 (defun note-local-functional (fun)
1318 (declare (type functional fun))
1319 (when (and (leaf-has-source-name-p fun)
1320 (eq (leaf-source-name fun) (functional-debug-name fun)))
1321 (let ((name (leaf-source-name fun)))
1322 (let ((defined-fun (gethash name *free-funs*)))
1323 (when (and defined-fun
1324 (defined-fun-p defined-fun)
1325 (eq (defined-fun-functional defined-fun) fun))
1326 (remhash name *free-funs*))))))
1328 ;;; Return functional for DEFINED-FUN which has been converted in policy
1329 ;;; corresponding to the current one, or NIL if no such functional exists.
1331 ;;; Also check that the parent of the functional is visible in the current
1333 (defun defined-fun-functional (defined-fun)
1334 (let ((functionals (defined-fun-functionals defined-fun)))
1336 (let* ((sample (car functionals))
1337 (there (lambda-parent (if (lambda-p sample)
1339 (optional-dispatch-main-entry sample)))))
1341 (labels ((lookup (here)
1342 (unless (eq here there)
1344 (lookup (lambda-parent here))
1345 ;; We looked up all the way up, and didn't find the parent
1346 ;; of the functional -- therefore it is nested in a lambda
1347 ;; we don't see, so return nil.
1348 (return-from defined-fun-functional nil)))))
1349 (lookup (lexenv-lambda *lexenv*)))))
1350 ;; Now find a functional whose policy matches the current one, if we already
1352 (let ((policy (lexenv-%policy *lexenv*)))
1353 (dolist (functional functionals)
1354 (when (equal policy (lexenv-%policy (functional-lexenv functional)))
1355 (return functional)))))))
1357 ;;; Do stuff to delete the semantic attachments of a REF node. When
1358 ;;; this leaves zero or one reference, we do a type dispatch off of
1359 ;;; the leaf to determine if a special action is appropriate.
1360 (defun delete-ref (ref)
1361 (declare (type ref ref))
1362 (let* ((leaf (ref-leaf ref))
1363 (refs (delq ref (leaf-refs leaf))))
1364 (setf (leaf-refs leaf) refs)
1369 (delete-lambda-var leaf))
1371 (ecase (functional-kind leaf)
1372 ((nil :let :mv-let :assignment :escape :cleanup)
1373 (aver (null (functional-entry-fun leaf)))
1374 (delete-lambda leaf))
1376 (unless (functional-has-external-references-p leaf)
1377 (delete-lambda leaf)))
1378 ((:deleted :zombie :optional))))
1380 (unless (eq (functional-kind leaf) :deleted)
1381 (delete-optional-dispatch leaf)))))
1384 (clambda (or (maybe-let-convert leaf)
1385 (maybe-convert-to-assignment leaf)))
1386 (lambda-var (reoptimize-lambda-var leaf))))
1389 (clambda (maybe-convert-to-assignment leaf))))))
1393 ;;; This function is called by people who delete nodes; it provides a
1394 ;;; way to indicate that the value of a lvar is no longer used. We
1395 ;;; null out the LVAR-DEST, set FLUSH-P in the blocks containing uses
1396 ;;; of LVAR and set COMPONENT-REOPTIMIZE.
1397 (defun flush-dest (lvar)
1398 (declare (type (or lvar null) lvar))
1400 (when (lvar-dynamic-extent lvar)
1401 (note-no-stack-allocation lvar :flush t))
1402 (setf (lvar-dest lvar) nil)
1403 (flush-lvar-externally-checkable-type lvar)
1405 (let ((prev (node-prev use)))
1406 (let ((block (ctran-block prev)))
1407 (reoptimize-component (block-component block) t)
1408 (setf (block-attributep (block-flags block)
1409 flush-p type-asserted type-check)
1411 (setf (node-lvar use) nil))
1412 (setf (lvar-uses lvar) nil))
1415 (defun delete-dest (lvar)
1417 (let* ((dest (lvar-dest lvar))
1418 (prev (node-prev dest)))
1419 (let ((block (ctran-block prev)))
1420 (unless (block-delete-p block)
1421 (mark-for-deletion block))))))
1423 ;;; Queue the block for deletion
1424 (defun delete-block-lazily (block)
1425 (declare (type cblock block))
1426 (unless (block-delete-p block)
1427 (setf (block-delete-p block) t)
1428 (push block (component-delete-blocks (block-component block)))))
1430 ;;; Do a graph walk backward from BLOCK, marking all predecessor
1431 ;;; blocks with the DELETE-P flag.
1432 (defun mark-for-deletion (block)
1433 (declare (type cblock block))
1434 (let* ((component (block-component block))
1435 (head (component-head component)))
1436 (labels ((helper (block)
1437 (delete-block-lazily block)
1438 (dolist (pred (block-pred block))
1439 (unless (or (block-delete-p pred)
1442 (unless (block-delete-p block)
1444 (setf (component-reanalyze component) t))))
1447 ;;; This function does what is necessary to eliminate the code in it
1448 ;;; from the IR1 representation. This involves unlinking it from its
1449 ;;; predecessors and successors and deleting various node-specific
1450 ;;; semantic information. BLOCK must be already removed from
1451 ;;; COMPONENT-DELETE-BLOCKS.
1452 (defun delete-block (block &optional silent)
1453 (declare (type cblock block))
1454 (aver (block-component block)) ; else block is already deleted!
1455 #!+high-security (aver (not (memq block (component-delete-blocks (block-component block)))))
1457 (note-block-deletion block))
1458 (setf (block-delete-p block) t)
1460 (dolist (b (block-pred block))
1461 (unlink-blocks b block)
1462 ;; In bug 147 the almost-all-blocks-have-a-successor invariant was
1463 ;; broken when successors were deleted without setting the
1464 ;; BLOCK-DELETE-P flags of their predececessors. Make sure that
1465 ;; doesn't happen again.
1466 (aver (not (and (null (block-succ b))
1467 (not (block-delete-p b))
1468 (not (eq b (component-head (block-component b))))))))
1469 (dolist (b (block-succ block))
1470 (unlink-blocks block b))
1472 (do-nodes-carefully (node block)
1473 (when (valued-node-p node)
1474 (delete-lvar-use node))
1476 (ref (delete-ref node))
1477 (cif (flush-dest (if-test node)))
1478 ;; The next two cases serve to maintain the invariant that a LET
1479 ;; always has a well-formed COMBINATION, REF and BIND. We delete
1480 ;; the lambda whenever we delete any of these, but we must be
1481 ;; careful that this LET has not already been partially deleted.
1483 (when (and (eq (basic-combination-kind node) :local)
1484 ;; Guards COMBINATION-LAMBDA agains the REF being deleted.
1485 (lvar-uses (basic-combination-fun node)))
1486 (let ((fun (combination-lambda node)))
1487 ;; If our REF was the second-to-last ref, and has been
1488 ;; deleted, then FUN may be a LET for some other
1490 (when (and (functional-letlike-p fun)
1491 (eq (let-combination fun) node))
1492 (delete-lambda fun))))
1493 (flush-dest (basic-combination-fun node))
1494 (dolist (arg (basic-combination-args node))
1495 (when arg (flush-dest arg))))
1497 (let ((lambda (bind-lambda node)))
1498 (unless (eq (functional-kind lambda) :deleted)
1499 (delete-lambda lambda))))
1501 (let ((value (exit-value node))
1502 (entry (exit-entry node)))
1506 (setf (entry-exits entry)
1507 (delq node (entry-exits entry))))))
1509 (dolist (exit (entry-exits node))
1510 (mark-for-deletion (node-block exit)))
1511 (let ((home (node-home-lambda node)))
1512 (setf (lambda-entries home) (delq node (lambda-entries home)))))
1514 (flush-dest (return-result node))
1515 (delete-return node))
1517 (flush-dest (set-value node))
1518 (let ((var (set-var node)))
1519 (setf (basic-var-sets var)
1520 (delete node (basic-var-sets var)))))
1522 (flush-dest (cast-value node)))))
1524 (remove-from-dfo block)
1527 ;;; Do stuff to indicate that the return node NODE is being deleted.
1528 (defun delete-return (node)
1529 (declare (type creturn node))
1530 (let* ((fun (return-lambda node))
1531 (tail-set (lambda-tail-set fun)))
1532 (aver (lambda-return fun))
1533 (setf (lambda-return fun) nil)
1534 (when (and tail-set (not (find-if #'lambda-return
1535 (tail-set-funs tail-set))))
1536 (setf (tail-set-type tail-set) *empty-type*)))
1539 ;;; If any of the VARS in FUN was never referenced and was not
1540 ;;; declared IGNORE, then complain.
1541 (defun note-unreferenced-vars (fun)
1542 (declare (type clambda fun))
1543 (dolist (var (lambda-vars fun))
1544 (unless (or (leaf-ever-used var)
1545 (lambda-var-ignorep var))
1546 (let ((*compiler-error-context* (lambda-bind fun)))
1547 (unless (policy *compiler-error-context* (= inhibit-warnings 3))
1548 ;; ANSI section "3.2.5 Exceptional Situations in the Compiler"
1549 ;; requires this to be no more than a STYLE-WARNING.
1551 (compiler-style-warn "The variable ~S is defined but never used."
1552 (leaf-debug-name var))
1553 ;; There's no reason to accept this kind of equivocation
1554 ;; when compiling our own code, though.
1556 (warn "The variable ~S is defined but never used."
1557 (leaf-debug-name var)))
1558 (setf (leaf-ever-used var) t)))) ; to avoid repeated warnings? -- WHN
1561 (defvar *deletion-ignored-objects* '(t nil))
1563 ;;; Return true if we can find OBJ in FORM, NIL otherwise. We bound
1564 ;;; our recursion so that we don't get lost in circular structures. We
1565 ;;; ignore the car of forms if they are a symbol (to prevent confusing
1566 ;;; function referencess with variables), and we also ignore anything
1568 (defun present-in-form (obj form depth)
1569 (declare (type (integer 0 20) depth))
1570 (cond ((= depth 20) nil)
1574 (let ((first (car form))
1576 (if (member first '(quote function))
1578 (or (and (not (symbolp first))
1579 (present-in-form obj first depth))
1580 (do ((l (cdr form) (cdr l))
1582 ((or (atom l) (> n 100))
1584 (declare (fixnum n))
1585 (when (present-in-form obj (car l) depth)
1588 ;;; This function is called on a block immediately before we delete
1589 ;;; it. We check to see whether any of the code about to die appeared
1590 ;;; in the original source, and emit a note if so.
1592 ;;; If the block was in a lambda is now deleted, then we ignore the
1593 ;;; whole block, since this case is picked off in DELETE-LAMBDA. We
1594 ;;; also ignore the deletion of CRETURN nodes, since it is somewhat
1595 ;;; reasonable for a function to not return, and there is a different
1596 ;;; note for that case anyway.
1598 ;;; If the actual source is an atom, then we use a bunch of heuristics
1599 ;;; to guess whether this reference really appeared in the original
1601 ;;; -- If a symbol, it must be interned and not a keyword.
1602 ;;; -- It must not be an easily introduced constant (T or NIL, a fixnum
1603 ;;; or a character.)
1604 ;;; -- The atom must be "present" in the original source form, and
1605 ;;; present in all intervening actual source forms.
1606 (defun note-block-deletion (block)
1607 (let ((home (block-home-lambda block)))
1608 (unless (eq (functional-kind home) :deleted)
1609 (do-nodes (node nil block)
1610 (let* ((path (node-source-path node))
1611 (first (first path)))
1612 (when (or (eq first 'original-source-start)
1614 (or (not (symbolp first))
1615 (let ((pkg (symbol-package first)))
1617 (not (eq pkg (symbol-package :end))))))
1618 (not (member first *deletion-ignored-objects*))
1619 (not (typep first '(or fixnum character)))
1621 (present-in-form first x 0))
1622 (source-path-forms path))
1623 (present-in-form first (find-original-source path)
1625 (unless (return-p node)
1626 (let ((*compiler-error-context* node))
1627 (compiler-notify 'code-deletion-note
1628 :format-control "deleting unreachable code"
1629 :format-arguments nil)))
1633 ;;; Delete a node from a block, deleting the block if there are no
1634 ;;; nodes left. We remove the node from the uses of its LVAR.
1636 ;;; If the node is the last node, there must be exactly one successor.
1637 ;;; We link all of our precedessors to the successor and unlink the
1638 ;;; block. In this case, we return T, otherwise NIL. If no nodes are
1639 ;;; left, and the block is a successor of itself, then we replace the
1640 ;;; only node with a degenerate exit node. This provides a way to
1641 ;;; represent the bodyless infinite loop, given the prohibition on
1642 ;;; empty blocks in IR1.
1643 (defun unlink-node (node)
1644 (declare (type node node))
1645 (when (valued-node-p node)
1646 (delete-lvar-use node))
1648 (let* ((ctran (node-next node))
1649 (next (and ctran (ctran-next ctran)))
1650 (prev (node-prev node))
1651 (block (ctran-block prev))
1652 (prev-kind (ctran-kind prev))
1653 (last (block-last block)))
1655 (setf (block-type-asserted block) t)
1656 (setf (block-test-modified block) t)
1658 (cond ((or (eq prev-kind :inside-block)
1659 (and (eq prev-kind :block-start)
1660 (not (eq node last))))
1661 (cond ((eq node last)
1662 (setf (block-last block) (ctran-use prev))
1663 (setf (node-next (ctran-use prev)) nil))
1665 (setf (ctran-next prev) next)
1666 (setf (node-prev next) prev)
1667 (when (if-p next) ; AOP wanted
1668 (reoptimize-lvar (if-test next)))))
1669 (setf (node-prev node) nil)
1672 (aver (eq prev-kind :block-start))
1673 (aver (eq node last))
1674 (let* ((succ (block-succ block))
1675 (next (first succ)))
1676 (aver (singleton-p succ))
1678 ((eq block (first succ))
1679 (with-ir1-environment-from-node node
1680 (let ((exit (make-exit)))
1681 (setf (ctran-next prev) nil)
1682 (link-node-to-previous-ctran exit prev)
1683 (setf (block-last block) exit)))
1684 (setf (node-prev node) nil)
1687 (aver (eq (block-start-cleanup block)
1688 (block-end-cleanup block)))
1689 (unlink-blocks block next)
1690 (dolist (pred (block-pred block))
1691 (change-block-successor pred block next))
1692 (when (block-delete-p block)
1693 (let ((component (block-component block)))
1694 (setf (component-delete-blocks component)
1695 (delq block (component-delete-blocks component)))))
1696 (remove-from-dfo block)
1697 (setf (block-delete-p block) t)
1698 (setf (node-prev node) nil)
1701 ;;; Return true if CTRAN has been deleted, false if it is still a valid
1703 (defun ctran-deleted-p (ctran)
1704 (declare (type ctran ctran))
1705 (let ((block (ctran-block ctran)))
1706 (or (not (block-component block))
1707 (block-delete-p block))))
1709 ;;; Return true if NODE has been deleted, false if it is still a valid
1711 (defun node-deleted (node)
1712 (declare (type node node))
1713 (let ((prev (node-prev node)))
1715 (ctran-deleted-p prev))))
1717 ;;; Delete all the blocks and functions in COMPONENT. We scan first
1718 ;;; marking the blocks as DELETE-P to prevent weird stuff from being
1719 ;;; triggered by deletion.
1720 (defun delete-component (component)
1721 (declare (type component component))
1722 (aver (null (component-new-functionals component)))
1723 (setf (component-kind component) :deleted)
1724 (do-blocks (block component)
1725 (delete-block-lazily block))
1726 (dolist (fun (component-lambdas component))
1727 (unless (eq (functional-kind fun) :deleted)
1728 (setf (functional-kind fun) nil)
1729 (setf (functional-entry-fun fun) nil)
1730 (setf (leaf-refs fun) nil)
1731 (delete-functional fun)))
1732 (clean-component component)
1735 ;;; Remove all pending blocks to be deleted. Return the nearest live
1736 ;;; block after or equal to BLOCK.
1737 (defun clean-component (component &optional block)
1738 (loop while (component-delete-blocks component)
1739 ;; actual deletion of a block may queue new blocks
1740 do (let ((current (pop (component-delete-blocks component))))
1741 (when (eq block current)
1742 (setq block (block-next block)))
1743 (delete-block current)))
1746 ;;; Convert code of the form
1747 ;;; (FOO ... (FUN ...) ...)
1749 ;;; (FOO ... ... ...).
1750 ;;; In other words, replace the function combination FUN by its
1751 ;;; arguments. If there are any problems with doing this, use GIVE-UP
1752 ;;; to blow out of whatever transform called this. Note, as the number
1753 ;;; of arguments changes, the transform must be prepared to return a
1754 ;;; lambda with a new lambda-list with the correct number of
1756 (defun splice-fun-args (lvar fun num-args)
1758 "If LVAR is a call to FUN with NUM-ARGS args, change those arguments to feed
1759 directly to the LVAR-DEST of LVAR, which must be a combination. If FUN
1760 is :ANY, the function name is not checked."
1761 (declare (type lvar lvar)
1763 (type index num-args))
1764 (let ((outside (lvar-dest lvar))
1765 (inside (lvar-uses lvar)))
1766 (aver (combination-p outside))
1767 (unless (combination-p inside)
1768 (give-up-ir1-transform))
1769 (let ((inside-fun (combination-fun inside)))
1770 (unless (or (eq fun :any)
1771 (eq (lvar-fun-name inside-fun) fun))
1772 (give-up-ir1-transform))
1773 (let ((inside-args (combination-args inside)))
1774 (unless (= (length inside-args) num-args)
1775 (give-up-ir1-transform))
1776 (let* ((outside-args (combination-args outside))
1777 (arg-position (position lvar outside-args))
1778 (before-args (subseq outside-args 0 arg-position))
1779 (after-args (subseq outside-args (1+ arg-position))))
1780 (dolist (arg inside-args)
1781 (setf (lvar-dest arg) outside)
1782 (flush-lvar-externally-checkable-type arg))
1783 (setf (combination-args inside) nil)
1784 (setf (combination-args outside)
1785 (append before-args inside-args after-args))
1786 (change-ref-leaf (lvar-uses inside-fun)
1787 (find-free-fun 'list "???"))
1788 (setf (combination-fun-info inside) (info :function :info 'list)
1789 (combination-kind inside) :known)
1790 (setf (node-derived-type inside) *wild-type*)
1794 ;;; Eliminate keyword arguments from the call (leaving the
1795 ;;; parameters in place.
1797 ;;; (FOO ... :BAR X :QUUX Y)
1801 ;;; SPECS is a list of (:KEYWORD PARAMETER) specifications.
1802 ;;; Returns the list of specified parameters names in the
1803 ;;; order they appeared in the call. N-POSITIONAL is the
1804 ;;; number of positional arguments in th call.
1805 (defun eliminate-keyword-args (call n-positional specs)
1806 (let* ((specs (copy-tree specs))
1807 (all (combination-args call))
1808 (new-args (reverse (subseq all 0 n-positional)))
1809 (key-args (subseq all n-positional))
1812 (loop while key-args
1813 do (let* ((key (pop key-args))
1814 (val (pop key-args))
1815 (keyword (if (constant-lvar-p key)
1817 (give-up-ir1-transform)))
1818 (spec (or (assoc keyword specs :test #'eq)
1819 (give-up-ir1-transform))))
1821 (push key flushed-keys)
1822 (push (second spec) parameters)
1823 ;; In case of duplicate keys.
1824 (setf (second spec) (gensym))))
1825 (dolist (key flushed-keys)
1827 (setf (combination-args call) (reverse new-args))
1828 (reverse parameters)))
1830 (defun extract-fun-args (lvar fun num-args)
1831 (declare (type lvar lvar)
1832 (type (or symbol list) fun)
1833 (type index num-args))
1834 (let ((fun (if (listp fun) fun (list fun))))
1835 (let ((inside (lvar-uses lvar)))
1836 (unless (combination-p inside)
1837 (give-up-ir1-transform))
1838 (let ((inside-fun (combination-fun inside)))
1839 (unless (member (lvar-fun-name inside-fun) fun)
1840 (give-up-ir1-transform))
1841 (let ((inside-args (combination-args inside)))
1842 (unless (= (length inside-args) num-args)
1843 (give-up-ir1-transform))
1844 (values (lvar-fun-name inside-fun) inside-args))))))
1846 (defun flush-combination (combination)
1847 (declare (type combination combination))
1848 (flush-dest (combination-fun combination))
1849 (dolist (arg (combination-args combination))
1851 (unlink-node combination)
1857 ;;; Change the LEAF that a REF refers to.
1858 (defun change-ref-leaf (ref leaf)
1859 (declare (type ref ref) (type leaf leaf))
1860 (unless (eq (ref-leaf ref) leaf)
1861 (push ref (leaf-refs leaf))
1863 (setf (ref-leaf ref) leaf)
1864 (setf (leaf-ever-used leaf) t)
1865 (let* ((ltype (leaf-type leaf))
1866 (vltype (make-single-value-type ltype)))
1867 (if (let* ((lvar (node-lvar ref))
1868 (dest (and lvar (lvar-dest lvar))))
1869 (and (basic-combination-p dest)
1870 (eq lvar (basic-combination-fun dest))
1871 (csubtypep ltype (specifier-type 'function))))
1872 (setf (node-derived-type ref) vltype)
1873 (derive-node-type ref vltype)))
1874 (reoptimize-lvar (node-lvar ref)))
1877 ;;; Change all REFS for OLD-LEAF to NEW-LEAF.
1878 (defun substitute-leaf (new-leaf old-leaf)
1879 (declare (type leaf new-leaf old-leaf))
1880 (dolist (ref (leaf-refs old-leaf))
1881 (change-ref-leaf ref new-leaf))
1884 ;;; like SUBSITUTE-LEAF, only there is a predicate on the REF to tell
1885 ;;; whether to substitute
1886 (defun substitute-leaf-if (test new-leaf old-leaf)
1887 (declare (type leaf new-leaf old-leaf) (type function test))
1888 (dolist (ref (leaf-refs old-leaf))
1889 (when (funcall test ref)
1890 (change-ref-leaf ref new-leaf)))
1893 ;;; Return a LEAF which represents the specified constant object. If
1894 ;;; the object is not in *CONSTANTS*, then we create a new constant
1895 ;;; LEAF and enter it. If we are producing a fasl file, make sure that
1896 ;;; MAKE-LOAD-FORM gets used on any parts of the constant that it
1899 ;;; We are allowed to coalesce things like EQUAL strings and bit-vectors
1900 ;;; when file-compiling, but not when using COMPILE.
1901 (defun find-constant (object &optional (name nil namep))
1902 (let ((faslp (producing-fasl-file)))
1903 (labels ((make-it ()
1906 (maybe-emit-make-load-forms object name)
1907 (maybe-emit-make-load-forms object)))
1908 (make-constant object))
1909 (core-coalesce-p (x)
1910 ;; True for things which retain their identity under EQUAL,
1911 ;; so we can safely share the same CONSTANT leaf between
1912 ;; multiple references.
1913 (or (typep x '(or symbol number character))
1914 ;; Amusingly enough, we see CLAMBDAs --among other things--
1915 ;; here, from compiling things like %ALLOCATE-CLOSUREs forms.
1916 ;; No point in stuffing them in the hash-table.
1917 (and (typep x 'instance)
1918 (not (or (leaf-p x) (node-p x))))))
1919 (file-coalesce-p (x)
1920 ;; CLHS 3.2.4.2.2: We are also allowed to coalesce various
1921 ;; other things when file-compiling.
1922 (or (core-coalesce-p x)
1924 (if (eq +code-coverage-unmarked+ (cdr x))
1925 ;; These are already coalesced, and the CAR should
1926 ;; always be OK, so no need to check.
1928 (unless (maybe-cyclic-p x) ; safe for EQUAL?
1930 ((atom y) (file-coalesce-p y))
1931 (unless (file-coalesce-p (car y))
1933 ;; We *could* coalesce base-strings as well,
1934 ;; but we'd need a separate hash-table for
1935 ;; that, since we are not allowed to coalesce
1936 ;; base-strings with non-base-strings.
1939 ;; in the cross-compiler, we coalesce
1940 ;; all strings with the same contents,
1941 ;; because we will end up dumping them
1942 ;; as base-strings anyway. In the
1943 ;; real compiler, we're not allowed to
1944 ;; coalesce regardless of string
1945 ;; specialized element type, so we
1946 ;; KLUDGE by coalescing only character
1947 ;; strings (the common case) and
1948 ;; punting on the other types.
1952 (vector character))))))
1954 (if faslp (file-coalesce-p x) (core-coalesce-p x))))
1955 (if (and (boundp '*constants*) (coalescep object))
1956 (or (gethash object *constants*)
1957 (setf (gethash object *constants*)
1961 ;;; Return true if VAR would have to be closed over if environment
1962 ;;; analysis ran now (i.e. if there are any uses that have a different
1963 ;;; home lambda than VAR's home.)
1964 (defun closure-var-p (var)
1965 (declare (type lambda-var var))
1966 (let ((home (lambda-var-home var)))
1967 (cond ((eq (functional-kind home) :deleted)
1969 (t (let ((home (lambda-home home)))
1972 :key #'node-home-lambda
1974 (or (frob (leaf-refs var))
1975 (frob (basic-var-sets var)))))))))
1977 ;;; If there is a non-local exit noted in ENTRY's environment that
1978 ;;; exits to CONT in that entry, then return it, otherwise return NIL.
1979 (defun find-nlx-info (exit)
1980 (declare (type exit exit))
1981 (let* ((entry (exit-entry exit))
1982 (cleanup (entry-cleanup entry))
1983 (block (first (block-succ (node-block exit)))))
1984 (dolist (nlx (physenv-nlx-info (node-physenv entry)) nil)
1985 (when (and (eq (nlx-info-block nlx) block)
1986 (eq (nlx-info-cleanup nlx) cleanup))
1989 (defun nlx-info-lvar (nlx)
1990 (declare (type nlx-info nlx))
1991 (node-lvar (block-last (nlx-info-target nlx))))
1993 ;;;; functional hackery
1995 (declaim (ftype (sfunction (functional) clambda) main-entry))
1996 (defun main-entry (functional)
1997 (etypecase functional
1998 (clambda functional)
2000 (optional-dispatch-main-entry functional))))
2002 ;;; RETURN true if FUNCTIONAL is a thing that can be treated like
2003 ;;; MV-BIND when it appears in an MV-CALL. All fixed arguments must be
2004 ;;; optional with null default and no SUPPLIED-P. There must be a
2005 ;;; &REST arg with no references.
2006 (declaim (ftype (sfunction (functional) boolean) looks-like-an-mv-bind))
2007 (defun looks-like-an-mv-bind (functional)
2008 (and (optional-dispatch-p functional)
2009 (do ((arg (optional-dispatch-arglist functional) (cdr arg)))
2011 (let ((info (lambda-var-arg-info (car arg))))
2012 (unless info (return nil))
2013 (case (arg-info-kind info)
2015 (when (or (arg-info-supplied-p info) (arg-info-default info))
2018 (return (and (null (cdr arg)) (null (leaf-refs (car arg))))))
2022 ;;; Return true if function is an external entry point. This is true
2023 ;;; of normal XEPs (:EXTERNAL kind) and also of top level lambdas
2024 ;;; (:TOPLEVEL kind.)
2026 (declare (type functional fun))
2027 (not (null (member (functional-kind fun) '(:external :toplevel)))))
2029 ;;; If LVAR's only use is a non-notinline global function reference,
2030 ;;; then return the referenced symbol, otherwise NIL. If NOTINLINE-OK
2031 ;;; is true, then we don't care if the leaf is NOTINLINE.
2032 (defun lvar-fun-name (lvar &optional notinline-ok)
2033 (declare (type lvar lvar))
2034 (let ((use (lvar-uses lvar)))
2036 (let ((leaf (ref-leaf use)))
2037 (if (and (global-var-p leaf)
2038 (eq (global-var-kind leaf) :global-function)
2039 (or (not (defined-fun-p leaf))
2040 (not (eq (defined-fun-inlinep leaf) :notinline))
2042 (leaf-source-name leaf)
2046 (defun lvar-fun-debug-name (lvar)
2047 (declare (type lvar lvar))
2048 (let ((uses (lvar-uses lvar)))
2050 (leaf-debug-name (ref-leaf use))))
2053 (mapcar #'name1 uses)))))
2055 ;;; Return the source name of a combination -- or signals an error
2056 ;;; if the function leaf is anonymous.
2057 (defun combination-fun-source-name (combination &optional (errorp t))
2058 (let ((leaf (ref-leaf (lvar-uses (combination-fun combination)))))
2059 (if (or errorp (leaf-has-source-name-p leaf))
2060 (values (leaf-source-name leaf) t)
2063 ;;; Return the COMBINATION node that is the call to the LET FUN.
2064 (defun let-combination (fun)
2065 (declare (type clambda fun))
2066 (aver (functional-letlike-p fun))
2067 (lvar-dest (node-lvar (first (leaf-refs fun)))))
2069 ;;; Return the initial value lvar for a LET variable, or NIL if there
2071 (defun let-var-initial-value (var)
2072 (declare (type lambda-var var))
2073 (let ((fun (lambda-var-home var)))
2074 (elt (combination-args (let-combination fun))
2075 (position-or-lose var (lambda-vars fun)))))
2077 ;;; Return the LAMBDA that is called by the local CALL.
2078 (defun combination-lambda (call)
2079 (declare (type basic-combination call))
2080 (aver (eq (basic-combination-kind call) :local))
2081 (ref-leaf (lvar-uses (basic-combination-fun call))))
2083 (defvar *inline-expansion-limit* 200
2085 "an upper limit on the number of inline function calls that will be expanded
2086 in any given code object (single function or block compilation)")
2088 ;;; Check whether NODE's component has exceeded its inline expansion
2089 ;;; limit, and warn if so, returning NIL.
2090 (defun inline-expansion-ok (node)
2091 (let ((expanded (incf (component-inline-expansions
2093 (node-block node))))))
2094 (cond ((> expanded *inline-expansion-limit*) nil)
2095 ((= expanded *inline-expansion-limit*)
2096 ;; FIXME: If the objective is to stop the recursive
2097 ;; expansion of inline functions, wouldn't it be more
2098 ;; correct to look back through surrounding expansions
2099 ;; (which are, I think, stored in the *CURRENT-PATH*, and
2100 ;; possibly stored elsewhere too) and suppress expansion
2101 ;; and print this warning when the function being proposed
2102 ;; for inline expansion is found there? (I don't like the
2103 ;; arbitrary numerical limit in principle, and I think
2104 ;; it'll be a nuisance in practice if we ever want the
2105 ;; compiler to be able to use WITH-COMPILATION-UNIT on
2106 ;; arbitrarily huge blocks of code. -- WHN)
2107 (let ((*compiler-error-context* node))
2108 (compiler-notify "*INLINE-EXPANSION-LIMIT* (~W) was exceeded, ~
2109 probably trying to~% ~
2110 inline a recursive function."
2111 *inline-expansion-limit*))
2115 ;;; Make sure that FUNCTIONAL is not let-converted or deleted.
2116 (defun assure-functional-live-p (functional)
2117 (declare (type functional functional))
2119 ;; looks LET-converted
2120 (functional-somewhat-letlike-p functional)
2121 ;; It's possible for a LET-converted function to end up
2122 ;; deleted later. In that case, for the purposes of this
2123 ;; analysis, it is LET-converted: LET-converted functionals
2124 ;; are too badly trashed to expand them inline, and deleted
2125 ;; LET-converted functionals are even worse.
2126 (memq (functional-kind functional) '(:deleted :zombie))))
2127 (throw 'locall-already-let-converted functional)))
2129 (defun assure-leaf-live-p (leaf)
2132 (when (lambda-var-deleted leaf)
2133 (throw 'locall-already-let-converted leaf)))
2135 (assure-functional-live-p leaf))))
2138 (defun call-full-like-p (call)
2139 (declare (type combination call))
2140 (let ((kind (basic-combination-kind call)))
2142 (and (eq kind :known)
2143 (let ((info (basic-combination-fun-info call)))
2145 (not (fun-info-ir2-convert info))
2146 (dolist (template (fun-info-templates info) t)
2147 (when (eq (template-ltn-policy template) :fast-safe)
2148 (multiple-value-bind (val win)
2149 (valid-fun-use call (template-type template))
2150 (when (or val (not win)) (return nil)))))))))))
2154 ;;; Apply a function to some arguments, returning a list of the values
2155 ;;; resulting of the evaluation. If an error is signalled during the
2156 ;;; application, then we produce a warning message using WARN-FUN and
2157 ;;; return NIL as our second value to indicate this. NODE is used as
2158 ;;; the error context for any error message, and CONTEXT is a string
2159 ;;; that is spliced into the warning.
2160 (declaim (ftype (sfunction ((or symbol function) list node function string)
2161 (values list boolean))
2163 (defun careful-call (function args node warn-fun context)
2165 (multiple-value-list
2166 (handler-case (apply function args)
2168 (let ((*compiler-error-context* node))
2169 (funcall warn-fun "Lisp error during ~A:~%~A" context condition)
2170 (return-from careful-call (values nil nil))))))
2173 ;;; Variations of SPECIFIER-TYPE for parsing possibly wrong
2176 ((deffrob (basic careful compiler transform)
2178 (defun ,careful (specifier)
2179 (handler-case (,basic specifier)
2180 (sb!kernel::arg-count-error (condition)
2181 (values nil (list (format nil "~A" condition))))
2182 (simple-error (condition)
2183 (values nil (list* (simple-condition-format-control condition)
2184 (simple-condition-format-arguments condition))))))
2185 (defun ,compiler (specifier)
2186 (multiple-value-bind (type error-args) (,careful specifier)
2188 (apply #'compiler-error error-args))))
2189 (defun ,transform (specifier)
2190 (multiple-value-bind (type error-args) (,careful specifier)
2192 (apply #'give-up-ir1-transform
2194 (deffrob specifier-type careful-specifier-type compiler-specifier-type ir1-transform-specifier-type)
2195 (deffrob values-specifier-type careful-values-specifier-type compiler-values-specifier-type ir1-transform-values-specifier-type))
2198 ;;;; utilities used at run-time for parsing &KEY args in IR1
2200 ;;; This function is used by the result of PARSE-DEFTRANSFORM to find
2201 ;;; the lvar for the value of the &KEY argument KEY in the list of
2202 ;;; lvars ARGS. It returns the lvar if the keyword is present, or NIL
2203 ;;; otherwise. The legality and constantness of the keywords should
2204 ;;; already have been checked.
2205 (declaim (ftype (sfunction (list keyword) (or lvar null))
2207 (defun find-keyword-lvar (args key)
2208 (do ((arg args (cddr arg)))
2210 (when (eq (lvar-value (first arg)) key)
2211 (return (second arg)))))
2213 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
2214 ;;; verify that alternating lvars in ARGS are constant and that there
2215 ;;; is an even number of args.
2216 (declaim (ftype (sfunction (list) boolean) check-key-args-constant))
2217 (defun check-key-args-constant (args)
2218 (do ((arg args (cddr arg)))
2220 (unless (and (rest arg)
2221 (constant-lvar-p (first arg)))
2224 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
2225 ;;; verify that the list of lvars ARGS is a well-formed &KEY arglist
2226 ;;; and that only keywords present in the list KEYS are supplied.
2227 (declaim (ftype (sfunction (list list) boolean) check-transform-keys))
2228 (defun check-transform-keys (args keys)
2229 (and (check-key-args-constant args)
2230 (do ((arg args (cddr arg)))
2232 (unless (member (lvar-value (first arg)) keys)
2237 ;;; Called by the expansion of the EVENT macro.
2238 (declaim (ftype (sfunction (event-info (or node null)) *) %event))
2239 (defun %event (info node)
2240 (incf (event-info-count info))
2241 (when (and (>= (event-info-level info) *event-note-threshold*)
2242 (policy (or node *lexenv*)
2243 (= inhibit-warnings 0)))
2244 (let ((*compiler-error-context* node))
2245 (compiler-notify (event-info-description info))))
2247 (let ((action (event-info-action info)))
2248 (when action (funcall action node))))
2251 (defun make-cast (value type policy)
2252 (declare (type lvar value)
2254 (type policy policy))
2255 (%make-cast :asserted-type type
2256 :type-to-check (maybe-weaken-check type policy)
2258 :derived-type (coerce-to-values type)))
2260 (defun cast-type-check (cast)
2261 (declare (type cast cast))
2262 (when (cast-reoptimize cast)
2263 (ir1-optimize-cast cast t))
2264 (cast-%type-check cast))
2266 (defun note-single-valuified-lvar (lvar)
2267 (declare (type (or lvar null) lvar))
2269 (let ((use (lvar-uses lvar)))
2271 (let ((leaf (ref-leaf use)))
2272 (when (and (lambda-var-p leaf)
2273 (null (rest (leaf-refs leaf))))
2274 (reoptimize-lambda-var leaf))))
2275 ((or (listp use) (combination-p use))
2276 (do-uses (node lvar)
2277 (setf (node-reoptimize node) t)
2278 (setf (block-reoptimize (node-block node)) t)
2279 (reoptimize-component (node-component node) :maybe)))))))
2281 ;;; Return true if LVAR's only use is a reference to a global function
2282 ;;; designator with one of the specified NAMES, that hasn't been
2283 ;;; declared NOTINLINE.
2284 (defun lvar-fun-is (lvar names)
2285 (declare (type lvar lvar) (list names))
2286 (let ((use (lvar-uses lvar)))
2288 (let* ((*lexenv* (node-lexenv use))
2289 (leaf (ref-leaf use))
2291 (cond ((global-var-p leaf)
2293 (and (eq (global-var-kind leaf) :global-function)
2294 (car (member (leaf-source-name leaf) names
2297 (let ((value (constant-value leaf)))
2298 (car (if (functionp value)
2303 (fdefinition name)))
2307 :test #'equal))))))))
2309 (not (fun-lexically-notinline-p name)))))))
2311 ;;; Return true if LVAR's only use is a call to one of the named functions
2312 ;;; (or any function if none are specified) with the specified number of
2313 ;;; of arguments (or any number if number is not specified)
2314 (defun lvar-matches (lvar &key fun-names arg-count)
2315 (let ((use (lvar-uses lvar)))
2316 (and (combination-p use)
2318 (multiple-value-bind (name ok)
2319 (combination-fun-source-name use nil)
2320 (and ok (member name fun-names :test #'eq))))
2322 (= arg-count (length (combination-args use)))))))
2324 ;;; True if the optional has a rest-argument.
2325 (defun optional-rest-p (opt)
2326 (dolist (var (optional-dispatch-arglist opt) nil)
2327 (let* ((info (when (lambda-var-p var)
2328 (lambda-var-arg-info var)))
2330 (arg-info-kind info))))
2331 (when (eq :rest kind)
2334 ;;; Don't substitute single-ref variables on high-debug / low speed, to
2335 ;;; improve the debugging experience. ...but don't bother keeping those
2336 ;;; from system lambdas.
2337 (defun preserve-single-use-debug-var-p (call var)
2338 (and (policy call (eql preserve-single-use-debug-variables 3))
2339 (or (not (lambda-var-p var))
2340 (not (lambda-system-lambda-p (lambda-var-home var))))))