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 (defun principal-lvar-use (lvar)
66 (let ((use (lvar-uses lvar
)))
68 (principal-lvar-use (cast-value use
))
71 ;;; Update lvar use information so that NODE is no longer a use of its
74 ;;; Note: if you call this function, you may have to do a
75 ;;; REOPTIMIZE-LVAR to inform IR1 optimization that something has
77 (declaim (ftype (sfunction (node) (values))
80 ;;; Just delete NODE from its LVAR uses; LVAR is preserved so it may
81 ;;; be given a new use.
82 (defun %delete-lvar-use
(node)
83 (let* ((lvar (node-lvar node
)))
85 (if (listp (lvar-uses lvar
))
86 (let ((new-uses (delq node
(lvar-uses lvar
))))
87 (setf (lvar-uses lvar
)
88 (if (singleton-p new-uses
)
91 (setf (lvar-uses lvar
) nil
))
92 (setf (node-lvar node
) nil
)))
94 ;;; Delete NODE from its LVAR uses; if LVAR has no other uses, delete
95 ;;; its DEST's block, which must be unreachable.
96 (defun delete-lvar-use (node)
97 (let ((lvar (node-lvar node
)))
99 (%delete-lvar-use node
)
100 (if (null (lvar-uses lvar
))
101 (binding* ((dest (lvar-dest lvar
) :exit-if-null
)
102 (() (not (node-deleted dest
)) :exit-if-null
)
103 (block (node-block dest
)))
104 (mark-for-deletion block
))
105 (reoptimize-lvar lvar
))))
108 ;;; Update lvar use information so that NODE uses LVAR.
110 ;;; Note: if you call this function, you may have to do a
111 ;;; REOPTIMIZE-LVAR to inform IR1 optimization that something has
113 (declaim (ftype (sfunction (node (or lvar null
)) (values)) add-lvar-use
))
114 (defun add-lvar-use (node lvar
)
115 (aver (not (node-lvar node
)))
117 (let ((uses (lvar-uses lvar
)))
118 (setf (lvar-uses lvar
)
125 (setf (node-lvar node
) lvar
)))
129 ;;; Return true if LVAR destination is executed immediately after
130 ;;; NODE. Cleanups are ignored.
131 (defun immediately-used-p (lvar node
)
132 (declare (type lvar lvar
) (type node node
))
133 (aver (eq (node-lvar node
) lvar
))
134 (let ((dest (lvar-dest lvar
)))
135 (acond ((node-next node
)
136 (eq (ctran-next it
) dest
))
137 (t (eq (block-start (first (block-succ (node-block node
))))
138 (node-prev dest
))))))
140 ;;;; lvar substitution
142 ;;; In OLD's DEST, replace OLD with NEW. NEW's DEST must initially be
143 ;;; NIL. We do not flush OLD's DEST.
144 (defun substitute-lvar (new old
)
145 (declare (type lvar old new
))
146 (aver (not (lvar-dest new
)))
147 (let ((dest (lvar-dest old
)))
150 (cif (setf (if-test dest
) new
))
151 (cset (setf (set-value dest
) new
))
152 (creturn (setf (return-result dest
) new
))
153 (exit (setf (exit-value dest
) new
))
155 (if (eq old
(basic-combination-fun dest
))
156 (setf (basic-combination-fun dest
) new
)
157 (setf (basic-combination-args dest
)
158 (nsubst new old
(basic-combination-args dest
)))))
159 (cast (setf (cast-value dest
) new
)))
161 (setf (lvar-dest old
) nil
)
162 (setf (lvar-dest new
) dest
)
163 (flush-lvar-externally-checkable-type new
))
166 ;;; Replace all uses of OLD with uses of NEW, where NEW has an
167 ;;; arbitary number of uses.
168 (defun substitute-lvar-uses (new old
)
169 (declare (type lvar old
)
170 (type (or lvar null
) new
))
173 (%delete-lvar-use node
)
175 (add-lvar-use node new
)))
177 (when new
(reoptimize-lvar new
))
180 ;;;; block starting/creation
182 ;;; Return the block that CTRAN is the start of, making a block if
183 ;;; necessary. This function is called by IR1 translators which may
184 ;;; cause a CTRAN to be used more than once. Every CTRAN which may be
185 ;;; used more than once must start a block by the time that anyone
186 ;;; does a USE-CTRAN on it.
188 ;;; We also throw the block into the next/prev list for the
189 ;;; *CURRENT-COMPONENT* so that we keep track of which blocks we have
191 (defun ctran-starts-block (ctran)
192 (declare (type ctran ctran
))
193 (ecase (ctran-kind ctran
)
195 (aver (not (ctran-block ctran
)))
196 (let* ((next (component-last-block *current-component
*))
197 (prev (block-prev next
))
198 (new-block (make-block ctran
)))
199 (setf (block-next new-block
) next
200 (block-prev new-block
) prev
201 (block-prev next
) new-block
202 (block-next prev
) new-block
203 (ctran-block ctran
) new-block
204 (ctran-kind ctran
) :block-start
)
205 (aver (not (ctran-use ctran
)))
208 (ctran-block ctran
))))
210 ;;; Ensure that CTRAN is the start of a block so that the use set can
211 ;;; be freely manipulated.
212 (defun ensure-block-start (ctran)
213 (declare (type ctran ctran
))
214 (let ((kind (ctran-kind ctran
)))
218 (setf (ctran-block ctran
)
219 (make-block-key :start ctran
))
220 (setf (ctran-kind ctran
) :block-start
))
222 (node-ends-block (ctran-use ctran
)))))
227 ;;; Filter values of LVAR through FORM, which must be an ordinary/mv
228 ;;; call. First argument must be 'DUMMY, which will be replaced with
229 ;;; LVAR. In case of an ordinary call the function should not have
230 ;;; return type NIL. We create a new "filtered" lvar.
232 ;;; TODO: remove preconditions.
233 (defun filter-lvar (lvar form
)
234 (declare (type lvar lvar
) (type list form
))
235 (let* ((dest (lvar-dest lvar
))
236 (ctran (node-prev dest
)))
237 (with-ir1-environment-from-node dest
239 (ensure-block-start ctran
)
240 (let* ((old-block (ctran-block ctran
))
241 (new-start (make-ctran))
242 (filtered-lvar (make-lvar))
243 (new-block (ctran-starts-block new-start
)))
245 ;; Splice in the new block before DEST, giving the new block
246 ;; all of DEST's predecessors.
247 (dolist (block (block-pred old-block
))
248 (change-block-successor block old-block new-block
))
250 (ir1-convert new-start ctran filtered-lvar form
)
252 ;; KLUDGE: Comments at the head of this function in CMU CL
253 ;; said that somewhere in here we
254 ;; Set the new block's start and end cleanups to the *start*
255 ;; cleanup of PREV's block. This overrides the incorrect
256 ;; default from WITH-IR1-ENVIRONMENT-FROM-NODE.
257 ;; Unfortunately I can't find any code which corresponds to this.
258 ;; Perhaps it was a stale comment? Or perhaps I just don't
259 ;; understand.. -- WHN 19990521
261 ;; Replace 'DUMMY with the LVAR. (We can find 'DUMMY because
262 ;; no LET conversion has been done yet.) The [mv-]combination
263 ;; code from the call in the form will be the use of the new
264 ;; check lvar. We substitute for the first argument of
266 (let* ((node (lvar-use filtered-lvar
))
267 (args (basic-combination-args node
))
268 (victim (first args
)))
269 (aver (eq (constant-value (ref-leaf (lvar-use victim
)))
272 (substitute-lvar filtered-lvar lvar
)
273 (substitute-lvar lvar victim
)
276 ;; Invoking local call analysis converts this call to a LET.
277 (locall-analyze-component *current-component
*))))
280 ;;; Delete NODE and VALUE. It may result in some calls becoming tail.
281 (defun delete-filter (node lvar value
)
282 (aver (eq (lvar-dest value
) node
))
283 (aver (eq (node-lvar node
) lvar
))
284 (cond (lvar (collect ((merges))
285 (when (return-p (lvar-dest lvar
))
287 (when (and (basic-combination-p use
)
288 (eq (basic-combination-kind use
) :local
))
290 (%delete-lvar-use node
)
291 (substitute-lvar-uses lvar value
)
294 (dolist (merge (merges))
295 (merge-tail-sets merge
)))))
296 (t (flush-dest value
)
297 (unlink-node node
))))
299 ;;;; miscellaneous shorthand functions
301 ;;; Return the home (i.e. enclosing non-LET) CLAMBDA for NODE. Since
302 ;;; the LEXENV-LAMBDA may be deleted, we must chain up the
303 ;;; LAMBDA-CALL-LEXENV thread until we find a CLAMBDA that isn't
304 ;;; deleted, and then return its home.
305 (defun node-home-lambda (node)
306 (declare (type node node
))
307 (do ((fun (lexenv-lambda (node-lexenv node
))
308 (lexenv-lambda (lambda-call-lexenv fun
))))
309 ((not (eq (functional-kind fun
) :deleted
))
311 (when (eq (lambda-home fun
) fun
)
314 #!-sb-fluid
(declaim (inline node-block
))
315 (defun node-block (node)
316 (ctran-block (node-prev node
)))
317 (declaim (ftype (sfunction (node) component
) node-component
))
318 (defun node-component (node)
319 (block-component (node-block node
)))
320 (declaim (ftype (sfunction (node) physenv
) node-physenv
))
321 (defun node-physenv (node)
322 (lambda-physenv (node-home-lambda node
)))
323 #!-sb-fluid
(declaim (inline node-dest
))
324 (defun node-dest (node)
325 (awhen (node-lvar node
) (lvar-dest it
)))
327 (declaim (ftype (sfunction (clambda) cblock
) lambda-block
))
328 (defun lambda-block (clambda)
329 (node-block (lambda-bind clambda
)))
330 (declaim (ftype (sfunction (clambda) component
) lambda-component
))
331 (defun lambda-component (clambda)
332 (block-component (lambda-block clambda
)))
334 (declaim (ftype (sfunction (cblock) node
) block-start-node
))
335 (defun block-start-node (block)
336 (ctran-next (block-start block
)))
338 ;;; Return the enclosing cleanup for environment of the first or last
340 (defun block-start-cleanup (block)
341 (node-enclosing-cleanup (block-start-node block
)))
342 (defun block-end-cleanup (block)
343 (node-enclosing-cleanup (block-last block
)))
345 ;;; Return the non-LET LAMBDA that holds BLOCK's code, or NIL
346 ;;; if there is none.
348 ;;; There can legitimately be no home lambda in dead code early in the
349 ;;; IR1 conversion process, e.g. when IR1-converting the SETQ form in
350 ;;; (BLOCK B (RETURN-FROM B) (SETQ X 3))
351 ;;; where the block is just a placeholder during parsing and doesn't
352 ;;; actually correspond to code which will be written anywhere.
353 (declaim (ftype (sfunction (cblock) (or clambda null
)) block-home-lambda-or-null
))
354 (defun block-home-lambda-or-null (block)
355 (if (node-p (block-last block
))
356 ;; This is the old CMU CL way of doing it.
357 (node-home-lambda (block-last block
))
358 ;; Now that SBCL uses this operation more aggressively than CMU
359 ;; CL did, the old CMU CL way of doing it can fail in two ways.
360 ;; 1. It can fail in a few cases even when a meaningful home
361 ;; lambda exists, e.g. in IR1-CONVERT of one of the legs of
363 ;; 2. It can fail when converting a form which is born orphaned
364 ;; so that it never had a meaningful home lambda, e.g. a form
365 ;; which follows a RETURN-FROM or GO form.
366 (let ((pred-list (block-pred block
)))
367 ;; To deal with case 1, we reason that
368 ;; previous-in-target-execution-order blocks should be in the
369 ;; same lambda, and that they seem in practice to be
370 ;; previous-in-compilation-order blocks too, so we look back
371 ;; to find one which is sufficiently initialized to tell us
372 ;; what the home lambda is.
374 ;; We could get fancy about this, flooding through the
375 ;; graph of all the previous blocks, but in practice it
376 ;; seems to work just to grab the first previous block and
378 (node-home-lambda (block-last (first pred-list
)))
379 ;; In case 2, we end up with an empty PRED-LIST and
380 ;; have to punt: There's no home lambda.
383 ;;; Return the non-LET LAMBDA that holds BLOCK's code.
384 (declaim (ftype (sfunction (cblock) clambda
) block-home-lambda
))
385 (defun block-home-lambda (block)
386 (block-home-lambda-or-null block
))
388 ;;; Return the IR1 physical environment for BLOCK.
389 (declaim (ftype (sfunction (cblock) physenv
) block-physenv
))
390 (defun block-physenv (block)
391 (lambda-physenv (block-home-lambda block
)))
393 ;;; Return the Top Level Form number of PATH, i.e. the ordinal number
394 ;;; of its original source's top level form in its compilation unit.
395 (defun source-path-tlf-number (path)
396 (declare (list path
))
399 ;;; Return the (reversed) list for the PATH in the original source
400 ;;; (with the Top Level Form number last).
401 (defun source-path-original-source (path)
402 (declare (list path
) (inline member
))
403 (cddr (member 'original-source-start path
:test
#'eq
)))
405 ;;; Return the Form Number of PATH's original source inside the Top
406 ;;; Level Form that contains it. This is determined by the order that
407 ;;; we walk the subforms of the top level source form.
408 (defun source-path-form-number (path)
409 (declare (list path
) (inline member
))
410 (cadr (member 'original-source-start path
:test
#'eq
)))
412 ;;; Return a list of all the enclosing forms not in the original
413 ;;; source that converted to get to this form, with the immediate
414 ;;; source for node at the start of the list.
415 (defun source-path-forms (path)
416 (subseq path
0 (position 'original-source-start path
)))
418 ;;; Return the innermost source form for NODE.
419 (defun node-source-form (node)
420 (declare (type node node
))
421 (let* ((path (node-source-path node
))
422 (forms (source-path-forms path
)))
425 (values (find-original-source path
)))))
427 ;;; Return NODE-SOURCE-FORM, T if lvar has a single use, otherwise
429 (defun lvar-source (lvar)
430 (let ((use (lvar-uses lvar
)))
433 (values (node-source-form use
) t
))))
435 ;;; Return the unique node, delivering a value to LVAR.
436 #!-sb-fluid
(declaim (inline lvar-use
))
437 (defun lvar-use (lvar)
438 (the (not list
) (lvar-uses lvar
)))
440 #!-sb-fluid
(declaim (inline lvar-has-single-use-p
))
441 (defun lvar-has-single-use-p (lvar)
442 (typep (lvar-uses lvar
) '(not list
)))
444 ;;; Return the LAMBDA that is CTRAN's home, or NIL if there is none.
445 (declaim (ftype (sfunction (ctran) (or clambda null
))
446 ctran-home-lambda-or-null
))
447 (defun ctran-home-lambda-or-null (ctran)
448 ;; KLUDGE: This function is a post-CMU-CL hack by WHN, and this
449 ;; implementation might not be quite right, or might be uglier than
450 ;; necessary. It appears that the original Python never found a need
451 ;; to do this operation. The obvious things based on
452 ;; NODE-HOME-LAMBDA of CTRAN-USE usually work; then if that fails,
453 ;; BLOCK-HOME-LAMBDA of CTRAN-BLOCK works, given that we
454 ;; generalize it enough to grovel harder when the simple CMU CL
455 ;; approach fails, and furthermore realize that in some exceptional
456 ;; cases it might return NIL. -- WHN 2001-12-04
457 (cond ((ctran-use ctran
)
458 (node-home-lambda (ctran-use ctran
)))
460 (block-home-lambda-or-null (ctran-block ctran
)))
462 (bug "confused about home lambda for ~S" ctran
))))
464 ;;; Return the LAMBDA that is CTRAN's home.
465 (declaim (ftype (sfunction (ctran) clambda
) ctran-home-lambda
))
466 (defun ctran-home-lambda (ctran)
467 (ctran-home-lambda-or-null ctran
))
469 #!-sb-fluid
(declaim (inline lvar-single-value-p
))
470 (defun lvar-single-value-p (lvar)
472 (let ((dest (lvar-dest lvar
)))
477 (eq (basic-combination-fun dest
) lvar
))
480 (declare (notinline lvar-single-value-p
))
481 (and (not (values-type-p (cast-asserted-type dest
)))
482 (lvar-single-value-p (node-lvar dest
)))))
486 (defun principal-lvar-end (lvar)
487 (loop for prev
= lvar then
(node-lvar dest
)
488 for dest
= (and prev
(lvar-dest prev
))
490 finally
(return (values dest prev
))))
492 (defun principal-lvar-single-valuify (lvar)
493 (loop for prev
= lvar then
(node-lvar dest
)
494 for dest
= (and prev
(lvar-dest prev
))
496 do
(setf (node-derived-type dest
)
497 (make-short-values-type (list (single-value-type
498 (node-derived-type dest
)))))
499 (reoptimize-lvar prev
)))
501 ;;; Return a new LEXENV just like DEFAULT except for the specified
502 ;;; slot values. Values for the alist slots are NCONCed to the
503 ;;; beginning of the current value, rather than replacing it entirely.
504 (defun make-lexenv (&key
(default *lexenv
*)
505 funs vars blocks tags
507 (lambda (lexenv-lambda default
))
508 (cleanup (lexenv-cleanup default
))
509 (policy (lexenv-policy default
)))
510 (macrolet ((frob (var slot
)
511 `(let ((old (,slot default
)))
515 (internal-make-lexenv
516 (frob funs lexenv-funs
)
517 (frob vars lexenv-vars
)
518 (frob blocks lexenv-blocks
)
519 (frob tags lexenv-tags
)
520 (frob type-restrictions lexenv-type-restrictions
)
521 lambda cleanup policy
)))
523 ;;; Makes a LEXENV, suitable for using in a MACROLET introduced
525 (defun make-restricted-lexenv (lexenv)
526 (flet ((fun-good-p (fun)
527 (destructuring-bind (name . thing
) fun
528 (declare (ignore name
))
532 (cons (aver (eq (car thing
) 'macro
))
535 (destructuring-bind (name . thing
) var
536 (declare (ignore name
))
539 (cons (aver (eq (car thing
) 'macro
))
541 (heap-alien-info nil
)))))
542 (internal-make-lexenv
543 (remove-if-not #'fun-good-p
(lexenv-funs lexenv
))
544 (remove-if-not #'var-good-p
(lexenv-vars lexenv
))
547 (lexenv-type-restrictions lexenv
) ; XXX
550 (lexenv-policy lexenv
))))
552 ;;;; flow/DFO/component hackery
554 ;;; Join BLOCK1 and BLOCK2.
555 (defun link-blocks (block1 block2
)
556 (declare (type cblock block1 block2
))
557 (setf (block-succ block1
)
558 (if (block-succ block1
)
559 (%link-blocks block1 block2
)
561 (push block1
(block-pred block2
))
563 (defun %link-blocks
(block1 block2
)
564 (declare (type cblock block1 block2
))
565 (let ((succ1 (block-succ block1
)))
566 (aver (not (memq block2 succ1
)))
567 (cons block2 succ1
)))
569 ;;; This is like LINK-BLOCKS, but we separate BLOCK1 and BLOCK2. If
570 ;;; this leaves a successor with a single predecessor that ends in an
571 ;;; IF, then set BLOCK-TEST-MODIFIED so that any test constraint will
572 ;;; now be able to be propagated to the successor.
573 (defun unlink-blocks (block1 block2
)
574 (declare (type cblock block1 block2
))
575 (let ((succ1 (block-succ block1
)))
576 (if (eq block2
(car succ1
))
577 (setf (block-succ block1
) (cdr succ1
))
578 (do ((succ (cdr succ1
) (cdr succ
))
580 ((eq (car succ
) block2
)
581 (setf (cdr prev
) (cdr succ
)))
584 (let ((new-pred (delq block1
(block-pred block2
))))
585 (setf (block-pred block2
) new-pred
)
586 (when (singleton-p new-pred
)
587 (let ((pred-block (first new-pred
)))
588 (when (if-p (block-last pred-block
))
589 (setf (block-test-modified pred-block
) t
)))))
592 ;;; Swing the succ/pred link between BLOCK and OLD to be between BLOCK
593 ;;; and NEW. If BLOCK ends in an IF, then we have to fix up the
594 ;;; consequent/alternative blocks to point to NEW. We also set
595 ;;; BLOCK-TEST-MODIFIED so that any test constraint will be applied to
596 ;;; the new successor.
597 (defun change-block-successor (block old new
)
598 (declare (type cblock new old block
))
599 (unlink-blocks block old
)
600 (let ((last (block-last block
))
601 (comp (block-component block
)))
602 (setf (component-reanalyze comp
) t
)
605 (setf (block-test-modified block
) t
)
606 (let* ((succ-left (block-succ block
))
607 (new (if (and (eq new
(component-tail comp
))
611 (unless (memq new succ-left
)
612 (link-blocks block new
))
613 (macrolet ((frob (slot)
614 `(when (eq (,slot last
) old
)
615 (setf (,slot last
) new
))))
617 (frob if-alternative
)
618 (when (eq (if-consequent last
)
619 (if-alternative last
))
620 (setf (component-reoptimize (block-component block
)) t
)))))
622 (unless (memq new
(block-succ block
))
623 (link-blocks block new
)))))
627 ;;; Unlink a block from the next/prev chain. We also null out the
629 (declaim (ftype (sfunction (cblock) (values)) remove-from-dfo
))
630 (defun remove-from-dfo (block)
631 (let ((next (block-next block
))
632 (prev (block-prev block
)))
633 (setf (block-component block
) nil
)
634 (setf (block-next prev
) next
)
635 (setf (block-prev next
) prev
))
638 ;;; Add BLOCK to the next/prev chain following AFTER. We also set the
639 ;;; COMPONENT to be the same as for AFTER.
640 (defun add-to-dfo (block after
)
641 (declare (type cblock block after
))
642 (let ((next (block-next after
))
643 (comp (block-component after
)))
644 (aver (not (eq (component-kind comp
) :deleted
)))
645 (setf (block-component block
) comp
)
646 (setf (block-next after
) block
)
647 (setf (block-prev block
) after
)
648 (setf (block-next block
) next
)
649 (setf (block-prev next
) block
))
652 ;;; Set the FLAG for all the blocks in COMPONENT to NIL, except for
653 ;;; the head and tail which are set to T.
654 (declaim (ftype (sfunction (component) (values)) clear-flags
))
655 (defun clear-flags (component)
656 (let ((head (component-head component
))
657 (tail (component-tail component
)))
658 (setf (block-flag head
) t
)
659 (setf (block-flag tail
) t
)
660 (do-blocks (block component
)
661 (setf (block-flag block
) nil
)))
664 ;;; Make a component with no blocks in it. The BLOCK-FLAG is initially
665 ;;; true in the head and tail blocks.
666 (declaim (ftype (sfunction () component
) make-empty-component
))
667 (defun make-empty-component ()
668 (let* ((head (make-block-key :start nil
:component nil
))
669 (tail (make-block-key :start nil
:component nil
))
670 (res (make-component head tail
)))
671 (setf (block-flag head
) t
)
672 (setf (block-flag tail
) t
)
673 (setf (block-component head
) res
)
674 (setf (block-component tail
) res
)
675 (setf (block-next head
) tail
)
676 (setf (block-prev tail
) head
)
679 ;;; Make NODE the LAST node in its block, splitting the block if necessary.
680 ;;; The new block is added to the DFO immediately following NODE's block.
681 (defun node-ends-block (node)
682 (declare (type node node
))
683 (let* ((block (node-block node
))
684 (start (node-next node
))
685 (last (block-last block
)))
686 (unless (eq last node
)
687 (aver (and (eq (ctran-kind start
) :inside-block
)
688 (not (block-delete-p block
))))
689 (let* ((succ (block-succ block
))
691 (make-block-key :start start
692 :component
(block-component block
)
693 :succ succ
:last last
)))
694 (setf (ctran-kind start
) :block-start
)
695 (setf (ctran-use start
) nil
)
696 (setf (block-last block
) node
)
697 (setf (node-next node
) nil
)
700 (cons new-block
(remove block
(block-pred b
)))))
701 (setf (block-succ block
) ())
702 (link-blocks block new-block
)
703 (add-to-dfo new-block block
)
704 (setf (component-reanalyze (block-component block
)) t
)
706 (do ((ctran start
(node-next (ctran-next ctran
))))
708 (setf (ctran-block ctran
) new-block
))
710 (setf (block-type-asserted block
) t
)
711 (setf (block-test-modified block
) t
))))
716 ;;; Deal with deleting the last (read) reference to a LAMBDA-VAR.
717 (defun delete-lambda-var (leaf)
718 (declare (type lambda-var leaf
))
720 ;; Iterate over all local calls flushing the corresponding argument,
721 ;; allowing the computation of the argument to be deleted. We also
722 ;; mark the LET for reoptimization, since it may be that we have
723 ;; deleted its last variable.
724 (let* ((fun (lambda-var-home leaf
))
725 (n (position leaf
(lambda-vars fun
))))
726 (dolist (ref (leaf-refs fun
))
727 (let* ((lvar (node-lvar ref
))
728 (dest (and lvar
(lvar-dest lvar
))))
729 (when (and (combination-p dest
)
730 (eq (basic-combination-fun dest
) lvar
)
731 (eq (basic-combination-kind dest
) :local
))
732 (let* ((args (basic-combination-args dest
))
734 (reoptimize-lvar arg
)
736 (setf (elt args n
) nil
))))))
738 ;; The LAMBDA-VAR may still have some SETs, but this doesn't cause
739 ;; too much difficulty, since we can efficiently implement
740 ;; write-only variables. We iterate over the SETs, marking their
741 ;; blocks for dead code flushing, since we can delete SETs whose
743 (dolist (set (lambda-var-sets leaf
))
744 (setf (block-flush-p (node-block set
)) t
))
748 ;;; Note that something interesting has happened to VAR.
749 (defun reoptimize-lambda-var (var)
750 (declare (type lambda-var var
))
751 (let ((fun (lambda-var-home var
)))
752 ;; We only deal with LET variables, marking the corresponding
753 ;; initial value arg as needing to be reoptimized.
754 (when (and (eq (functional-kind fun
) :let
)
756 (do ((args (basic-combination-args
757 (lvar-dest (node-lvar (first (leaf-refs fun
)))))
759 (vars (lambda-vars fun
) (cdr vars
)))
761 (reoptimize-lvar (car args
))))))
764 ;;; Delete a function that has no references. This need only be called
765 ;;; on functions that never had any references, since otherwise
766 ;;; DELETE-REF will handle the deletion.
767 (defun delete-functional (fun)
768 (aver (and (null (leaf-refs fun
))
769 (not (functional-entry-fun fun
))))
771 (optional-dispatch (delete-optional-dispatch fun
))
772 (clambda (delete-lambda fun
)))
775 ;;; Deal with deleting the last reference to a CLAMBDA. It is called
776 ;;; in two situations: when the lambda is unreachable (so that its
777 ;;; body may be deleted), and when it is an effectless LET (in this
778 ;;; case its body is reachable and is not completely "its"). We set
779 ;;; FUNCTIONAL-KIND to :DELETED and rely on IR1-OPTIMIZE to delete its
781 (defun delete-lambda (clambda)
782 (declare (type clambda clambda
))
783 (let ((original-kind (functional-kind clambda
))
784 (bind (lambda-bind clambda
)))
785 (aver (not (member original-kind
'(:deleted
:toplevel
))))
786 (aver (not (functional-has-external-references-p clambda
)))
787 (setf (functional-kind clambda
) :deleted
)
788 (setf (lambda-bind clambda
) nil
)
790 (when bind
; CLAMBDA is deleted due to unreachability
791 (labels ((delete-children (lambda)
792 (dolist (child (lambda-children lambda
))
793 (cond ((eq (functional-kind child
) :deleted
)
794 (delete-children child
))
796 (delete-lambda child
))))
797 (setf (lambda-children lambda
) nil
)
798 (setf (lambda-parent lambda
) nil
)))
799 (delete-children clambda
)))
800 (dolist (let (lambda-lets clambda
))
801 (setf (lambda-bind let
) nil
)
802 (setf (functional-kind let
) :deleted
))
804 ;; LET may be deleted if its BIND is unreachable. Autonomous
805 ;; function may be deleted if it has no reachable references.
806 (unless (member original-kind
'(:let
:mv-let
:assignment
))
807 (dolist (ref (lambda-refs clambda
))
808 (mark-for-deletion (node-block ref
))))
810 ;; (The IF test is (FUNCTIONAL-SOMEWHAT-LETLIKE-P CLAMBDA), except
811 ;; that we're using the old value of the KIND slot, not the
812 ;; current slot value, which has now been set to :DELETED.)
813 (if (member original-kind
'(:let
:mv-let
:assignment
))
814 (let ((home (lambda-home clambda
)))
815 (setf (lambda-lets home
) (delete clambda
(lambda-lets home
))))
816 ;; If the function isn't a LET, we unlink the function head
817 ;; and tail from the component head and tail to indicate that
818 ;; the code is unreachable. We also delete the function from
819 ;; COMPONENT-LAMBDAS (it won't be there before local call
820 ;; analysis, but no matter.) If the lambda was never
821 ;; referenced, we give a note.
822 (let* ((bind-block (node-block bind
))
823 (component (block-component bind-block
))
824 (return (lambda-return clambda
))
825 (return-block (and return
(node-block return
))))
826 (unless (leaf-ever-used clambda
)
827 (let ((*compiler-error-context
* bind
))
828 (compiler-notify 'code-deletion-note
829 :format-control
"deleting unused function~:[.~;~:*~% ~S~]"
830 :format-arguments
(list (leaf-debug-name clambda
)))))
831 (unless (block-delete-p bind-block
)
832 (unlink-blocks (component-head component
) bind-block
))
833 (when (and return-block
(not (block-delete-p return-block
)))
834 (mark-for-deletion return-block
)
835 (unlink-blocks return-block
(component-tail component
)))
836 (setf (component-reanalyze component
) t
)
837 (let ((tails (lambda-tail-set clambda
)))
838 (setf (tail-set-funs tails
)
839 (delete clambda
(tail-set-funs tails
)))
840 (setf (lambda-tail-set clambda
) nil
))
841 (setf (component-lambdas component
)
842 (delq clambda
(component-lambdas component
)))))
844 ;; If the lambda is an XEP, then we null out the ENTRY-FUN in its
845 ;; ENTRY-FUN so that people will know that it is not an entry
847 (when (eq original-kind
:external
)
848 (let ((fun (functional-entry-fun clambda
)))
849 (setf (functional-entry-fun fun
) nil
)
850 (when (optional-dispatch-p fun
)
851 (delete-optional-dispatch fun
)))))
855 ;;; Deal with deleting the last reference to an OPTIONAL-DISPATCH. We
856 ;;; have to be a bit more careful than with lambdas, since DELETE-REF
857 ;;; is used both before and after local call analysis. Afterward, all
858 ;;; references to still-existing OPTIONAL-DISPATCHes have been moved
859 ;;; to the XEP, leaving it with no references at all. So we look at
860 ;;; the XEP to see whether an optional-dispatch is still really being
861 ;;; used. But before local call analysis, there are no XEPs, and all
862 ;;; references are direct.
864 ;;; When we do delete the OPTIONAL-DISPATCH, we grovel all of its
865 ;;; entry-points, making them be normal lambdas, and then deleting the
866 ;;; ones with no references. This deletes any e-p lambdas that were
867 ;;; either never referenced, or couldn't be deleted when the last
868 ;;; reference was deleted (due to their :OPTIONAL kind.)
870 ;;; Note that the last optional entry point may alias the main entry,
871 ;;; so when we process the main entry, its KIND may have been changed
872 ;;; to NIL or even converted to a LETlike value.
873 (defun delete-optional-dispatch (leaf)
874 (declare (type optional-dispatch leaf
))
875 (let ((entry (functional-entry-fun leaf
)))
876 (unless (and entry
(leaf-refs entry
))
877 (aver (or (not entry
) (eq (functional-kind entry
) :deleted
)))
878 (setf (functional-kind leaf
) :deleted
)
881 (unless (eq (functional-kind fun
) :deleted
)
882 (aver (eq (functional-kind fun
) :optional
))
883 (setf (functional-kind fun
) nil
)
884 (let ((refs (leaf-refs fun
)))
888 (or (maybe-let-convert fun
)
889 (maybe-convert-to-assignment fun
)))
891 (maybe-convert-to-assignment fun
)))))))
893 (dolist (ep (optional-dispatch-entry-points leaf
))
894 (when (promise-ready-p ep
)
896 (when (optional-dispatch-more-entry leaf
)
897 (frob (optional-dispatch-more-entry leaf
)))
898 (let ((main (optional-dispatch-main-entry leaf
)))
899 (when (eq (functional-kind main
) :optional
)
904 ;;; Do stuff to delete the semantic attachments of a REF node. When
905 ;;; this leaves zero or one reference, we do a type dispatch off of
906 ;;; the leaf to determine if a special action is appropriate.
907 (defun delete-ref (ref)
908 (declare (type ref ref
))
909 (let* ((leaf (ref-leaf ref
))
910 (refs (delq ref
(leaf-refs leaf
))))
911 (setf (leaf-refs leaf
) refs
)
916 (delete-lambda-var leaf
))
918 (ecase (functional-kind leaf
)
919 ((nil :let
:mv-let
:assignment
:escape
:cleanup
)
920 (aver (null (functional-entry-fun leaf
)))
921 (delete-lambda leaf
))
923 (delete-lambda leaf
))
924 ((:deleted
:optional
))))
926 (unless (eq (functional-kind leaf
) :deleted
)
927 (delete-optional-dispatch leaf
)))))
930 (clambda (or (maybe-let-convert leaf
)
931 (maybe-convert-to-assignment leaf
)))
932 (lambda-var (reoptimize-lambda-var leaf
))))
935 (clambda (maybe-convert-to-assignment leaf
))))))
939 ;;; This function is called by people who delete nodes; it provides a
940 ;;; way to indicate that the value of a lvar is no longer used. We
941 ;;; null out the LVAR-DEST, set FLUSH-P in the blocks containing uses
942 ;;; of LVAR and set COMPONENT-REOPTIMIZE.
943 (defun flush-dest (lvar)
944 (declare (type (or lvar null
) lvar
))
946 (setf (lvar-dest lvar
) nil
)
947 (flush-lvar-externally-checkable-type lvar
)
949 (let ((prev (node-prev use
)))
950 (let ((block (ctran-block prev
)))
951 (setf (component-reoptimize (block-component block
)) t
)
952 (setf (block-attributep (block-flags block
) flush-p type-asserted
)
954 (setf (node-lvar use
) nil
))
955 (setf (lvar-uses lvar
) nil
))
958 (defun delete-dest (lvar)
960 (let* ((dest (lvar-dest lvar
))
961 (prev (node-prev dest
)))
962 (let ((block (ctran-block prev
)))
963 (unless (block-delete-p block
)
964 (mark-for-deletion block
))))))
966 ;;; Do a graph walk backward from BLOCK, marking all predecessor
967 ;;; blocks with the DELETE-P flag.
968 (defun mark-for-deletion (block)
969 (declare (type cblock block
))
970 (let* ((component (block-component block
))
971 (head (component-head component
)))
972 (labels ((helper (block)
973 (setf (block-delete-p block
) t
)
974 (dolist (pred (block-pred block
))
975 (unless (or (block-delete-p pred
)
978 (unless (block-delete-p block
)
980 (setf (component-reanalyze component
) t
))))
983 ;;; This function does what is necessary to eliminate the code in it
984 ;;; from the IR1 representation. This involves unlinking it from its
985 ;;; predecessors and successors and deleting various node-specific
986 ;;; semantic information.
987 (defun delete-block (block &optional silent
)
988 (declare (type cblock block
))
989 (aver (block-component block
)) ; else block is already deleted!
991 (note-block-deletion block
))
992 (setf (block-delete-p block
) t
)
994 (dolist (b (block-pred block
))
995 (unlink-blocks b block
)
996 ;; In bug 147 the almost-all-blocks-have-a-successor invariant was
997 ;; broken when successors were deleted without setting the
998 ;; BLOCK-DELETE-P flags of their predececessors. Make sure that
999 ;; doesn't happen again.
1000 (aver (not (and (null (block-succ b
))
1001 (not (block-delete-p b
))
1002 (not (eq b
(component-head (block-component b
))))))))
1003 (dolist (b (block-succ block
))
1004 (unlink-blocks block b
))
1006 (do-nodes-carefully (node block
)
1007 (when (valued-node-p node
)
1008 (delete-lvar-use node
))
1010 (ref (delete-ref node
))
1011 (cif (flush-dest (if-test node
)))
1012 ;; The next two cases serve to maintain the invariant that a LET
1013 ;; always has a well-formed COMBINATION, REF and BIND. We delete
1014 ;; the lambda whenever we delete any of these, but we must be
1015 ;; careful that this LET has not already been partially deleted.
1017 (when (and (eq (basic-combination-kind node
) :local
)
1018 ;; Guards COMBINATION-LAMBDA agains the REF being deleted.
1019 (lvar-uses (basic-combination-fun node
)))
1020 (let ((fun (combination-lambda node
)))
1021 ;; If our REF was the second-to-last ref, and has been
1022 ;; deleted, then FUN may be a LET for some other
1024 (when (and (functional-letlike-p fun
)
1025 (eq (let-combination fun
) node
))
1026 (delete-lambda fun
))))
1027 (flush-dest (basic-combination-fun node
))
1028 (dolist (arg (basic-combination-args node
))
1029 (when arg
(flush-dest arg
))))
1031 (let ((lambda (bind-lambda node
)))
1032 (unless (eq (functional-kind lambda
) :deleted
)
1033 (delete-lambda lambda
))))
1035 (let ((value (exit-value node
))
1036 (entry (exit-entry node
)))
1040 (setf (entry-exits entry
)
1041 (delq node
(entry-exits entry
))))))
1043 (dolist (exit (entry-exits node
))
1044 (mark-for-deletion (node-block exit
)))
1045 (let ((home (node-home-lambda node
)))
1046 (setf (lambda-entries home
) (delq node
(lambda-entries home
)))))
1048 (flush-dest (return-result node
))
1049 (delete-return node
))
1051 (flush-dest (set-value node
))
1052 (let ((var (set-var node
)))
1053 (setf (basic-var-sets var
)
1054 (delete node
(basic-var-sets var
)))))
1056 (flush-dest (cast-value node
)))))
1058 (remove-from-dfo block
)
1061 ;;; Do stuff to indicate that the return node NODE is being deleted.
1062 (defun delete-return (node)
1063 (declare (type creturn node
))
1064 (let* ((fun (return-lambda node
))
1065 (tail-set (lambda-tail-set fun
)))
1066 (aver (lambda-return fun
))
1067 (setf (lambda-return fun
) nil
)
1068 (when (and tail-set
(not (find-if #'lambda-return
1069 (tail-set-funs tail-set
))))
1070 (setf (tail-set-type tail-set
) *empty-type
*)))
1073 ;;; If any of the VARS in FUN was never referenced and was not
1074 ;;; declared IGNORE, then complain.
1075 (defun note-unreferenced-vars (fun)
1076 (declare (type clambda fun
))
1077 (dolist (var (lambda-vars fun
))
1078 (unless (or (leaf-ever-used var
)
1079 (lambda-var-ignorep var
))
1080 (let ((*compiler-error-context
* (lambda-bind fun
)))
1081 (unless (policy *compiler-error-context
* (= inhibit-warnings
3))
1082 ;; ANSI section "3.2.5 Exceptional Situations in the Compiler"
1083 ;; requires this to be no more than a STYLE-WARNING.
1084 (compiler-style-warn "The variable ~S is defined but never used."
1085 (leaf-debug-name var
)))
1086 (setf (leaf-ever-used var
) t
)))) ; to avoid repeated warnings? -- WHN
1089 (defvar *deletion-ignored-objects
* '(t nil
))
1091 ;;; Return true if we can find OBJ in FORM, NIL otherwise. We bound
1092 ;;; our recursion so that we don't get lost in circular structures. We
1093 ;;; ignore the car of forms if they are a symbol (to prevent confusing
1094 ;;; function referencess with variables), and we also ignore anything
1096 (defun present-in-form (obj form depth
)
1097 (declare (type (integer 0 20) depth
))
1098 (cond ((= depth
20) nil
)
1102 (let ((first (car form
))
1104 (if (member first
'(quote function
))
1106 (or (and (not (symbolp first
))
1107 (present-in-form obj first depth
))
1108 (do ((l (cdr form
) (cdr l
))
1110 ((or (atom l
) (> n
100))
1112 (declare (fixnum n
))
1113 (when (present-in-form obj
(car l
) depth
)
1116 ;;; This function is called on a block immediately before we delete
1117 ;;; it. We check to see whether any of the code about to die appeared
1118 ;;; in the original source, and emit a note if so.
1120 ;;; If the block was in a lambda is now deleted, then we ignore the
1121 ;;; whole block, since this case is picked off in DELETE-LAMBDA. We
1122 ;;; also ignore the deletion of CRETURN nodes, since it is somewhat
1123 ;;; reasonable for a function to not return, and there is a different
1124 ;;; note for that case anyway.
1126 ;;; If the actual source is an atom, then we use a bunch of heuristics
1127 ;;; to guess whether this reference really appeared in the original
1129 ;;; -- If a symbol, it must be interned and not a keyword.
1130 ;;; -- It must not be an easily introduced constant (T or NIL, a fixnum
1131 ;;; or a character.)
1132 ;;; -- The atom must be "present" in the original source form, and
1133 ;;; present in all intervening actual source forms.
1134 (defun note-block-deletion (block)
1135 (let ((home (block-home-lambda block
)))
1136 (unless (eq (functional-kind home
) :deleted
)
1137 (do-nodes (node nil block
)
1138 (let* ((path (node-source-path node
))
1139 (first (first path
)))
1140 (when (or (eq first
'original-source-start
)
1142 (or (not (symbolp first
))
1143 (let ((pkg (symbol-package first
)))
1145 (not (eq pkg
(symbol-package :end
))))))
1146 (not (member first
*deletion-ignored-objects
*))
1147 (not (typep first
'(or fixnum character
)))
1149 (present-in-form first x
0))
1150 (source-path-forms path
))
1151 (present-in-form first
(find-original-source path
)
1153 (unless (return-p node
)
1154 (let ((*compiler-error-context
* node
))
1155 (compiler-notify 'code-deletion-note
1156 :format-control
"deleting unreachable code"
1157 :format-arguments nil
)))
1161 ;;; Delete a node from a block, deleting the block if there are no
1162 ;;; nodes left. We remove the node from the uses of its LVAR.
1164 ;;; If the node is the last node, there must be exactly one successor.
1165 ;;; We link all of our precedessors to the successor and unlink the
1166 ;;; block. In this case, we return T, otherwise NIL. If no nodes are
1167 ;;; left, and the block is a successor of itself, then we replace the
1168 ;;; only node with a degenerate exit node. This provides a way to
1169 ;;; represent the bodyless infinite loop, given the prohibition on
1170 ;;; empty blocks in IR1.
1171 (defun unlink-node (node)
1172 (declare (type node node
))
1173 (when (valued-node-p node
)
1174 (delete-lvar-use node
))
1176 (let* ((ctran (node-next node
))
1177 (next (and ctran
(ctran-next ctran
)))
1178 (prev (node-prev node
))
1179 (block (ctran-block prev
))
1180 (prev-kind (ctran-kind prev
))
1181 (last (block-last block
)))
1183 (setf (block-type-asserted block
) t
)
1184 (setf (block-test-modified block
) t
)
1186 (cond ((or (eq prev-kind
:inside-block
)
1187 (and (eq prev-kind
:block-start
)
1188 (not (eq node last
))))
1189 (cond ((eq node last
)
1190 (setf (block-last block
) (ctran-use prev
))
1191 (setf (node-next (ctran-use prev
)) nil
))
1193 (setf (ctran-next prev
) next
)
1194 (setf (node-prev next
) prev
)
1195 (when (if-p next
) ; AOP wanted
1196 (reoptimize-lvar (if-test next
)))))
1197 (setf (node-prev node
) nil
)
1200 (aver (eq prev-kind
:block-start
))
1201 (aver (eq node last
))
1202 (let* ((succ (block-succ block
))
1203 (next (first succ
)))
1204 (aver (singleton-p succ
))
1206 ((eq block
(first succ
))
1207 (with-ir1-environment-from-node node
1208 (let ((exit (make-exit)))
1209 (setf (ctran-next prev
) nil
)
1210 (link-node-to-previous-ctran exit prev
)
1211 (setf (block-last block
) exit
)))
1212 (setf (node-prev node
) nil
)
1215 (aver (eq (block-start-cleanup block
)
1216 (block-end-cleanup block
)))
1217 (unlink-blocks block next
)
1218 (dolist (pred (block-pred block
))
1219 (change-block-successor pred block next
))
1220 (remove-from-dfo block
)
1221 (setf (block-delete-p block
) t
)
1222 (setf (node-prev node
) nil
)
1225 ;;; Return true if NODE has been deleted, false if it is still a valid
1227 (defun node-deleted (node)
1228 (declare (type node node
))
1229 (let ((prev (node-prev node
)))
1231 (let ((block (ctran-block prev
)))
1232 (and (block-component block
)
1233 (not (block-delete-p block
))))))))
1235 ;;; Delete all the blocks and functions in COMPONENT. We scan first
1236 ;;; marking the blocks as DELETE-P to prevent weird stuff from being
1237 ;;; triggered by deletion.
1238 (defun delete-component (component)
1239 (declare (type component component
))
1240 (aver (null (component-new-functionals component
)))
1241 (setf (component-kind component
) :deleted
)
1242 (do-blocks (block component
)
1243 (setf (block-delete-p block
) t
))
1244 (dolist (fun (component-lambdas component
))
1245 (unless (eq (functional-kind fun
) :deleted
)
1246 (setf (functional-kind fun
) nil
)
1247 (setf (functional-entry-fun fun
) nil
)
1248 (setf (leaf-refs fun
) nil
)
1249 (delete-functional fun
)))
1250 (do-blocks (block component
)
1251 (delete-block block
))
1254 ;;; Convert code of the form
1255 ;;; (FOO ... (FUN ...) ...)
1257 ;;; (FOO ... ... ...).
1258 ;;; In other words, replace the function combination FUN by its
1259 ;;; arguments. If there are any problems with doing this, use GIVE-UP
1260 ;;; to blow out of whatever transform called this. Note, as the number
1261 ;;; of arguments changes, the transform must be prepared to return a
1262 ;;; lambda with a new lambda-list with the correct number of
1264 (defun extract-fun-args (lvar fun num-args
)
1266 "If LVAR is a call to FUN with NUM-ARGS args, change those arguments
1267 to feed directly to the LVAR-DEST of LVAR, which must be a
1269 (declare (type lvar lvar
)
1271 (type index num-args
))
1272 (let ((outside (lvar-dest lvar
))
1273 (inside (lvar-uses lvar
)))
1274 (aver (combination-p outside
))
1275 (unless (combination-p inside
)
1276 (give-up-ir1-transform))
1277 (let ((inside-fun (combination-fun inside
)))
1278 (unless (eq (lvar-fun-name inside-fun
) fun
)
1279 (give-up-ir1-transform))
1280 (let ((inside-args (combination-args inside
)))
1281 (unless (= (length inside-args
) num-args
)
1282 (give-up-ir1-transform))
1283 (let* ((outside-args (combination-args outside
))
1284 (arg-position (position lvar outside-args
))
1285 (before-args (subseq outside-args
0 arg-position
))
1286 (after-args (subseq outside-args
(1+ arg-position
))))
1287 (dolist (arg inside-args
)
1288 (setf (lvar-dest arg
) outside
)
1289 (flush-lvar-externally-checkable-type arg
))
1290 (setf (combination-args inside
) nil
)
1291 (setf (combination-args outside
)
1292 (append before-args inside-args after-args
))
1293 (change-ref-leaf (lvar-uses inside-fun
)
1294 (find-free-fun 'list
"???"))
1295 (setf (combination-kind inside
)
1296 (info :function
:info
'list
))
1297 (setf (node-derived-type inside
) *wild-type
*)
1301 (defun flush-combination (combination)
1302 (declare (type combination combination
))
1303 (flush-dest (combination-fun combination
))
1304 (dolist (arg (combination-args combination
))
1306 (unlink-node combination
)
1312 ;;; Change the LEAF that a REF refers to.
1313 (defun change-ref-leaf (ref leaf
)
1314 (declare (type ref ref
) (type leaf leaf
))
1315 (unless (eq (ref-leaf ref
) leaf
)
1316 (push ref
(leaf-refs leaf
))
1318 (setf (ref-leaf ref
) leaf
)
1319 (setf (leaf-ever-used leaf
) t
)
1320 (let* ((ltype (leaf-type leaf
))
1321 (vltype (make-single-value-type ltype
)))
1322 (if (let* ((lvar (node-lvar ref
))
1323 (dest (and lvar
(lvar-dest lvar
))))
1324 (and (basic-combination-p dest
)
1325 (eq lvar
(basic-combination-fun dest
))
1326 (csubtypep ltype
(specifier-type 'function
))))
1327 (setf (node-derived-type ref
) vltype
)
1328 (derive-node-type ref vltype
)))
1329 (reoptimize-lvar (node-lvar ref
)))
1332 ;;; Change all REFS for OLD-LEAF to NEW-LEAF.
1333 (defun substitute-leaf (new-leaf old-leaf
)
1334 (declare (type leaf new-leaf old-leaf
))
1335 (dolist (ref (leaf-refs old-leaf
))
1336 (change-ref-leaf ref new-leaf
))
1339 ;;; like SUBSITUTE-LEAF, only there is a predicate on the REF to tell
1340 ;;; whether to substitute
1341 (defun substitute-leaf-if (test new-leaf old-leaf
)
1342 (declare (type leaf new-leaf old-leaf
) (type function test
))
1343 (dolist (ref (leaf-refs old-leaf
))
1344 (when (funcall test ref
)
1345 (change-ref-leaf ref new-leaf
)))
1348 ;;; Return a LEAF which represents the specified constant object. If
1349 ;;; the object is not in *CONSTANTS*, then we create a new constant
1350 ;;; LEAF and enter it.
1351 (defun find-constant (object)
1353 ;; FIXME: What is the significance of this test? ("things
1354 ;; that are worth uniquifying"?)
1355 '(or symbol number character instance
))
1356 (or (gethash object
*constants
*)
1357 (setf (gethash object
*constants
*)
1358 (make-constant :value object
1359 :%source-name
'.anonymous.
1360 :type
(ctype-of object
)
1361 :where-from
:defined
)))
1362 (make-constant :value object
1363 :%source-name
'.anonymous.
1364 :type
(ctype-of object
)
1365 :where-from
:defined
)))
1367 ;;; Return true if VAR would have to be closed over if environment
1368 ;;; analysis ran now (i.e. if there are any uses that have a different
1369 ;;; home lambda than VAR's home.)
1370 (defun closure-var-p (var)
1371 (declare (type lambda-var var
))
1372 (let ((home (lambda-var-home var
)))
1373 (cond ((eq (functional-kind home
) :deleted
)
1375 (t (let ((home (lambda-home home
)))
1378 :key
#'node-home-lambda
1380 (or (frob (leaf-refs var
))
1381 (frob (basic-var-sets var
)))))))))
1383 ;;; If there is a non-local exit noted in ENTRY's environment that
1384 ;;; exits to CONT in that entry, then return it, otherwise return NIL.
1385 (defun find-nlx-info (exit)
1386 (declare (type exit exit
))
1387 (let* ((entry (exit-entry exit
))
1388 (entry-cleanup (entry-cleanup entry
)))
1389 (dolist (nlx (physenv-nlx-info (node-physenv entry
)) nil
)
1390 (when (eq (nlx-info-exit nlx
) exit
)
1393 ;;;; functional hackery
1395 (declaim (ftype (sfunction (functional) clambda
) main-entry
))
1396 (defun main-entry (functional)
1397 (etypecase functional
1398 (clambda functional
)
1400 (optional-dispatch-main-entry functional
))))
1402 ;;; RETURN true if FUNCTIONAL is a thing that can be treated like
1403 ;;; MV-BIND when it appears in an MV-CALL. All fixed arguments must be
1404 ;;; optional with null default and no SUPPLIED-P. There must be a
1405 ;;; &REST arg with no references.
1406 (declaim (ftype (sfunction (functional) boolean
) looks-like-an-mv-bind
))
1407 (defun looks-like-an-mv-bind (functional)
1408 (and (optional-dispatch-p functional
)
1409 (do ((arg (optional-dispatch-arglist functional
) (cdr arg
)))
1411 (let ((info (lambda-var-arg-info (car arg
))))
1412 (unless info
(return nil
))
1413 (case (arg-info-kind info
)
1415 (when (or (arg-info-supplied-p info
) (arg-info-default info
))
1418 (return (and (null (cdr arg
)) (null (leaf-refs (car arg
))))))
1422 ;;; Return true if function is an external entry point. This is true
1423 ;;; of normal XEPs (:EXTERNAL kind) and also of top level lambdas
1424 ;;; (:TOPLEVEL kind.)
1426 (declare (type functional fun
))
1427 (not (null (member (functional-kind fun
) '(:external
:toplevel
)))))
1429 ;;; If LVAR's only use is a non-notinline global function reference,
1430 ;;; then return the referenced symbol, otherwise NIL. If NOTINLINE-OK
1431 ;;; is true, then we don't care if the leaf is NOTINLINE.
1432 (defun lvar-fun-name (lvar &optional notinline-ok
)
1433 (declare (type lvar lvar
))
1434 (let ((use (lvar-uses lvar
)))
1436 (let ((leaf (ref-leaf use
)))
1437 (if (and (global-var-p leaf
)
1438 (eq (global-var-kind leaf
) :global-function
)
1439 (or (not (defined-fun-p leaf
))
1440 (not (eq (defined-fun-inlinep leaf
) :notinline
))
1442 (leaf-source-name leaf
)
1446 ;;; Return the source name of a combination. (This is an idiom
1447 ;;; which was used in CMU CL. I gather it always works. -- WHN)
1448 (defun combination-fun-source-name (combination)
1449 (let ((ref (lvar-uses (combination-fun combination
))))
1450 (leaf-source-name (ref-leaf ref
))))
1452 ;;; Return the COMBINATION node that is the call to the LET FUN.
1453 (defun let-combination (fun)
1454 (declare (type clambda fun
))
1455 (aver (functional-letlike-p fun
))
1456 (lvar-dest (node-lvar (first (leaf-refs fun
)))))
1458 ;;; Return the initial value lvar for a LET variable, or NIL if there
1460 (defun let-var-initial-value (var)
1461 (declare (type lambda-var var
))
1462 (let ((fun (lambda-var-home var
)))
1463 (elt (combination-args (let-combination fun
))
1464 (position-or-lose var
(lambda-vars fun
)))))
1466 ;;; Return the LAMBDA that is called by the local CALL.
1467 (defun combination-lambda (call)
1468 (declare (type basic-combination call
))
1469 (aver (eq (basic-combination-kind call
) :local
))
1470 (ref-leaf (lvar-uses (basic-combination-fun call
))))
1472 (defvar *inline-expansion-limit
* 200
1474 "an upper limit on the number of inline function calls that will be expanded
1475 in any given code object (single function or block compilation)")
1477 ;;; Check whether NODE's component has exceeded its inline expansion
1478 ;;; limit, and warn if so, returning NIL.
1479 (defun inline-expansion-ok (node)
1480 (let ((expanded (incf (component-inline-expansions
1482 (node-block node
))))))
1483 (cond ((> expanded
*inline-expansion-limit
*) nil
)
1484 ((= expanded
*inline-expansion-limit
*)
1485 ;; FIXME: If the objective is to stop the recursive
1486 ;; expansion of inline functions, wouldn't it be more
1487 ;; correct to look back through surrounding expansions
1488 ;; (which are, I think, stored in the *CURRENT-PATH*, and
1489 ;; possibly stored elsewhere too) and suppress expansion
1490 ;; and print this warning when the function being proposed
1491 ;; for inline expansion is found there? (I don't like the
1492 ;; arbitrary numerical limit in principle, and I think
1493 ;; it'll be a nuisance in practice if we ever want the
1494 ;; compiler to be able to use WITH-COMPILATION-UNIT on
1495 ;; arbitrarily huge blocks of code. -- WHN)
1496 (let ((*compiler-error-context
* node
))
1497 (compiler-notify "*INLINE-EXPANSION-LIMIT* (~W) was exceeded, ~
1498 probably trying to~% ~
1499 inline a recursive function."
1500 *inline-expansion-limit
*))
1504 ;;; Make sure that FUNCTIONAL is not let-converted or deleted.
1505 (defun assure-functional-live-p (functional)
1506 (declare (type functional functional
))
1508 ;; looks LET-converted
1509 (functional-somewhat-letlike-p functional
)
1510 ;; It's possible for a LET-converted function to end up
1511 ;; deleted later. In that case, for the purposes of this
1512 ;; analysis, it is LET-converted: LET-converted functionals
1513 ;; are too badly trashed to expand them inline, and deleted
1514 ;; LET-converted functionals are even worse.
1515 (eql (functional-kind functional
) :deleted
)))
1516 (throw 'locall-already-let-converted functional
)))
1520 ;;; Apply a function to some arguments, returning a list of the values
1521 ;;; resulting of the evaluation. If an error is signalled during the
1522 ;;; application, then we produce a warning message using WARN-FUN and
1523 ;;; return NIL as our second value to indicate this. NODE is used as
1524 ;;; the error context for any error message, and CONTEXT is a string
1525 ;;; that is spliced into the warning.
1526 (declaim (ftype (sfunction ((or symbol function
) list node function string
)
1527 (values list boolean
))
1529 (defun careful-call (function args node warn-fun context
)
1531 (multiple-value-list
1532 (handler-case (apply function args
)
1534 (let ((*compiler-error-context
* node
))
1535 (funcall warn-fun
"Lisp error during ~A:~%~A" context condition
)
1536 (return-from careful-call
(values nil nil
))))))
1539 ;;; Variations of SPECIFIER-TYPE for parsing possibly wrong
1542 ((deffrob (basic careful compiler transform
)
1544 (defun ,careful
(specifier)
1545 (handler-case (,basic specifier
)
1546 (sb!kernel
::arg-count-error
(condition)
1547 (values nil
(list (format nil
"~A" condition
))))
1548 (simple-error (condition)
1549 (values nil
(list* (simple-condition-format-control condition
)
1550 (simple-condition-format-arguments condition
))))))
1551 (defun ,compiler
(specifier)
1552 (multiple-value-bind (type error-args
) (,careful specifier
)
1554 (apply #'compiler-error error-args
))))
1555 (defun ,transform
(specifier)
1556 (multiple-value-bind (type error-args
) (,careful specifier
)
1558 (apply #'give-up-ir1-transform
1560 (deffrob specifier-type careful-specifier-type compiler-specifier-type ir1-transform-specifier-type
)
1561 (deffrob values-specifier-type careful-values-specifier-type compiler-values-specifier-type ir1-transform-values-specifier-type
))
1564 ;;;; utilities used at run-time for parsing &KEY args in IR1
1566 ;;; This function is used by the result of PARSE-DEFTRANSFORM to find
1567 ;;; the lvar for the value of the &KEY argument KEY in the list of
1568 ;;; lvars ARGS. It returns the lvar if the keyword is present, or NIL
1569 ;;; otherwise. The legality and constantness of the keywords should
1570 ;;; already have been checked.
1571 (declaim (ftype (sfunction (list keyword
) (or lvar null
))
1573 (defun find-keyword-lvar (args key
)
1574 (do ((arg args
(cddr arg
)))
1576 (when (eq (lvar-value (first arg
)) key
)
1577 (return (second arg
)))))
1579 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
1580 ;;; verify that alternating lvars in ARGS are constant and that there
1581 ;;; is an even number of args.
1582 (declaim (ftype (sfunction (list) boolean
) check-key-args-constant
))
1583 (defun check-key-args-constant (args)
1584 (do ((arg args
(cddr arg
)))
1586 (unless (and (rest arg
)
1587 (constant-lvar-p (first arg
)))
1590 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
1591 ;;; verify that the list of lvars ARGS is a well-formed &KEY arglist
1592 ;;; and that only keywords present in the list KEYS are supplied.
1593 (declaim (ftype (sfunction (list list
) boolean
) check-transform-keys
))
1594 (defun check-transform-keys (args keys
)
1595 (and (check-key-args-constant args
)
1596 (do ((arg args
(cddr arg
)))
1598 (unless (member (lvar-value (first arg
)) keys
)
1603 ;;; Called by the expansion of the EVENT macro.
1604 (declaim (ftype (sfunction (event-info (or node null
)) *) %event
))
1605 (defun %event
(info node
)
1606 (incf (event-info-count info
))
1607 (when (and (>= (event-info-level info
) *event-note-threshold
*)
1608 (policy (or node
*lexenv
*)
1609 (= inhibit-warnings
0)))
1610 (let ((*compiler-error-context
* node
))
1611 (compiler-notify (event-info-description info
))))
1613 (let ((action (event-info-action info
)))
1614 (when action
(funcall action node
))))
1617 (defun make-cast (value type policy
)
1618 (declare (type lvar value
)
1620 (type policy policy
))
1621 (%make-cast
:asserted-type type
1622 :type-to-check
(maybe-weaken-check type policy
)
1624 :derived-type
(coerce-to-values type
)))
1626 (defun cast-type-check (cast)
1627 (declare (type cast cast
))
1628 (when (cast-reoptimize cast
)
1629 (ir1-optimize-cast cast t
))
1630 (cast-%type-check cast
))
1632 (defun note-single-valuified-lvar (lvar)
1633 (declare (type (or lvar null
) lvar
))
1635 (let ((use (lvar-uses lvar
)))
1637 (let ((leaf (ref-leaf use
)))
1638 (when (and (lambda-var-p leaf
)
1639 (null (rest (leaf-refs leaf
))))
1640 (reoptimize-lambda-var leaf
))))
1641 ((or (listp use
) (combination-p use
))
1642 (do-uses (node lvar
)
1643 (setf (node-reoptimize node
) t
)
1644 (setf (block-reoptimize (node-block node
)) t
)
1645 (setf (component-reoptimize (node-component node
)) t
)))))))