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 none in
18 ;;; its function. If Node has no cleanup, but is in a let, then we must still
19 ;;; 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 node
40 (let* ((start (make-continuation))
41 (block (continuation-starts-block start))
42 (cont (make-continuation))
44 (make-lexenv :cleanup cleanup)
46 (change-block-successor block1 block2 block)
47 (link-blocks block block2)
48 (ir1-convert start cont form)
49 (setf (block-last block) (continuation-use cont))
52 ;;;; continuation use hacking
54 ;;; Return a list of all the nodes which use Cont.
55 (declaim (ftype (function (continuation) list) find-uses))
56 (defun find-uses (cont)
57 (ecase (continuation-kind cont)
58 ((:block-start :deleted-block-start)
59 (block-start-uses (continuation-block cont)))
60 (:inside-block (list (continuation-use cont)))
64 ;;; Update continuation use information so that NODE is no longer a
65 ;;; use of its CONT. If the old continuation doesn't start its block,
66 ;;; then we don't update the BLOCK-START-USES, since it will be
67 ;;; deleted when we are done.
69 ;;; Note: if you call this function, you may have to do a
70 ;;; REOPTIMIZE-CONTINUATION to inform IR1 optimization that something
72 (declaim (ftype (function (node) (values)) delete-continuation-use))
73 (defun delete-continuation-use (node)
74 (let* ((cont (node-cont node))
75 (block (continuation-block cont)))
76 (ecase (continuation-kind cont)
78 ((:block-start :deleted-block-start)
79 (let ((uses (delete node (block-start-uses block))))
80 (setf (block-start-uses block) uses)
81 (setf (continuation-use cont)
82 (if (cdr uses) nil (car uses)))))
84 (setf (continuation-kind cont) :unused)
85 (setf (continuation-block cont) nil)
86 (setf (continuation-use cont) nil)
87 (setf (continuation-next cont) nil)))
88 (setf (node-cont node) nil))
91 ;;; Update continuation use information so that NODE uses CONT. If
92 ;;; CONT is :UNUSED, then we set its block to NODE's NODE-BLOCK (which
95 ;;; Note: if you call this function, you may have to do a
96 ;;; REOPTIMIZE-CONTINUATION to inform IR1 optimization that something
98 (declaim (ftype (function (node continuation) (values)) add-continuation-use))
99 (defun add-continuation-use (node cont)
100 (aver (not (node-cont node)))
101 (let ((block (continuation-block cont)))
102 (ecase (continuation-kind cont)
106 (let ((block (node-block node)))
108 (setf (continuation-block cont) block))
109 (setf (continuation-kind cont) :inside-block)
110 (setf (continuation-use cont) node))
111 ((:block-start :deleted-block-start)
112 (let ((uses (cons node (block-start-uses block))))
113 (setf (block-start-uses block) uses)
114 (setf (continuation-use cont)
115 (if (cdr uses) nil (car uses)))))))
116 (setf (node-cont node) cont)
119 ;;; Return true if CONT is the NODE-CONT for NODE and CONT is
120 ;;; transferred to immediately after the evaluation of NODE.
121 (defun immediately-used-p (cont node)
122 (declare (type continuation cont) (type node node))
123 (and (eq (node-cont node) cont)
124 (not (eq (continuation-kind cont) :deleted))
125 (let ((cblock (continuation-block cont))
126 (nblock (node-block node)))
127 (or (eq cblock nblock)
128 (let ((succ (block-succ nblock)))
129 (and (= (length succ) 1)
130 (eq (first succ) cblock)))))))
132 ;;;; continuation substitution
134 ;;; In OLD's DEST, replace OLD with NEW. NEW's DEST must initially be
135 ;;; NIL. When we are done, we call FLUSH-DEST on OLD to clear its DEST
136 ;;; and to note potential optimization opportunities.
137 (defun substitute-continuation (new old)
138 (declare (type continuation old new))
139 (aver (not (continuation-dest new)))
140 (let ((dest (continuation-dest old)))
143 (cif (setf (if-test dest) new))
144 (cset (setf (set-value dest) new))
145 (creturn (setf (return-result dest) new))
146 (exit (setf (exit-value dest) new))
148 (if (eq old (basic-combination-fun dest))
149 (setf (basic-combination-fun dest) new)
150 (setf (basic-combination-args dest)
151 (nsubst new old (basic-combination-args dest))))))
154 (setf (continuation-dest new) dest))
157 ;;; Replace all uses of OLD with uses of NEW, where NEW has an
158 ;;; arbitary number of uses. If NEW will end up with more than one
159 ;;; use, then we must arrange for it to start a block if it doesn't
161 (defun substitute-continuation-uses (new old)
162 (declare (type continuation old new))
163 (unless (and (eq (continuation-kind new) :unused)
164 (eq (continuation-kind old) :inside-block))
165 (ensure-block-start new))
168 (delete-continuation-use node)
169 (add-continuation-use node new))
170 (dolist (lexenv-use (continuation-lexenv-uses old))
171 (setf (cadr lexenv-use) new))
173 (reoptimize-continuation new)
176 ;;;; block starting/creation
178 ;;; Return the block that CONT is the start of, making a block if
179 ;;; necessary. This function is called by IR1 translators which may
180 ;;; cause a continuation to be used more than once. Every continuation
181 ;;; which may be used more than once must start a block by the time
182 ;;; that anyone does a USE-CONTINUATION on it.
184 ;;; We also throw the block into the next/prev list for the
185 ;;; *CURRENT-COMPONENT* so that we keep track of which blocks we have
187 (defun continuation-starts-block (cont)
188 (declare (type continuation cont))
189 (ecase (continuation-kind cont)
191 (aver (not (continuation-block cont)))
192 (let* ((head (component-head *current-component*))
193 (next (block-next head))
194 (new-block (make-block cont)))
195 (setf (block-next new-block) next)
196 (setf (block-prev new-block) head)
197 (setf (block-prev next) new-block)
198 (setf (block-next head) new-block)
199 (setf (continuation-block cont) new-block)
200 (setf (continuation-use cont) nil)
201 (setf (continuation-kind cont) :block-start)
204 (continuation-block cont))))
206 ;;; Ensure that Cont is the start of a block (or deleted) so that the use
207 ;;; set can be freely manipulated.
208 ;;; -- If the continuation is :Unused or is :Inside-Block and the Cont of Last
209 ;;; in its block, then we make it the start of a new deleted block.
210 ;;; -- If the continuation is :Inside-Block inside a block, then we split the
211 ;;; block using Node-Ends-Block, which makes the continuation be a
213 (defun ensure-block-start (cont)
214 (declare (type continuation cont))
215 (let ((kind (continuation-kind cont)))
217 ((:deleted :block-start :deleted-block-start))
218 ((:unused :inside-block)
219 (let ((block (continuation-block cont)))
220 (cond ((or (eq kind :unused)
221 (eq (node-cont (block-last block)) cont))
222 (setf (continuation-block cont)
223 (make-block-key :start cont
225 :start-uses (find-uses cont)))
226 (setf (continuation-kind cont) :deleted-block-start))
228 (node-ends-block (continuation-use cont))))))))
231 ;;;; miscellaneous shorthand functions
233 ;;; Return the home (i.e. enclosing non-let) lambda for Node. Since the
234 ;;; LEXENV-LAMBDA may be deleted, we must chain up the LAMBDA-CALL-LEXENV
235 ;;; thread until we find a lambda that isn't deleted, and then return its home.
236 (declaim (maybe-inline node-home-lambda))
237 (defun node-home-lambda (node)
238 (declare (type node node))
239 (do ((fun (lexenv-lambda (node-lexenv node))
240 (lexenv-lambda (lambda-call-lexenv fun))))
241 ((not (eq (functional-kind fun) :deleted))
243 (when (eq (lambda-home fun) fun)
246 #!-sb-fluid (declaim (inline node-block node-tlf-number))
247 (declaim (maybe-inline node-environment))
248 (defun node-block (node)
249 (declare (type node node))
250 (the cblock (continuation-block (node-prev node))))
251 (defun node-environment (node)
252 (declare (type node node))
253 #!-sb-fluid (declare (inline node-home-lambda))
254 (the environment (lambda-environment (node-home-lambda node))))
256 ;;; Return the enclosing cleanup for environment of the first or last node
258 (defun block-start-cleanup (block)
259 (declare (type cblock block))
260 (node-enclosing-cleanup (continuation-next (block-start block))))
261 (defun block-end-cleanup (block)
262 (declare (type cblock block))
263 (node-enclosing-cleanup (block-last block)))
265 ;;; Return the non-let lambda that holds Block's code.
266 (defun block-home-lambda (block)
267 (declare (type cblock block))
268 #!-sb-fluid (declare (inline node-home-lambda))
269 (node-home-lambda (block-last block)))
271 ;;; Return the IR1 environment for Block.
272 (defun block-environment (block)
273 (declare (type cblock block))
274 #!-sb-fluid (declare (inline node-home-lambda))
275 (lambda-environment (node-home-lambda (block-last block))))
277 ;;; Return the Top Level Form number of path, i.e. the ordinal number
278 ;;; of its original source's top-level form in its compilation unit.
279 (defun source-path-tlf-number (path)
280 (declare (list path))
283 ;;; Return the (reversed) list for the path in the original source
284 ;;; (with the Top Level Form number last).
285 (defun source-path-original-source (path)
286 (declare (list path) (inline member))
287 (cddr (member 'original-source-start path :test #'eq)))
289 ;;; Return the Form Number of Path's original source inside the Top
290 ;;; Level Form that contains it. This is determined by the order that
291 ;;; we walk the subforms of the top level source form.
292 (defun source-path-form-number (path)
293 (declare (list path) (inline member))
294 (cadr (member 'original-source-start path :test #'eq)))
296 ;;; Return a list of all the enclosing forms not in the original
297 ;;; source that converted to get to this form, with the immediate
298 ;;; source for node at the start of the list.
299 (defun source-path-forms (path)
300 (subseq path 0 (position 'original-source-start path)))
302 ;;; Return the innermost source form for Node.
303 (defun node-source-form (node)
304 (declare (type node node))
305 (let* ((path (node-source-path node))
306 (forms (source-path-forms path)))
309 (values (find-original-source path)))))
311 ;;; Return NODE-SOURCE-FORM, T if continuation has a single use,
312 ;;; otherwise NIL, NIL.
313 (defun continuation-source (cont)
314 (let ((use (continuation-use cont)))
316 (values (node-source-form use) t)
319 ;;; Return a new LEXENV just like DEFAULT except for the specified
320 ;;; slot values. Values for the alist slots are NCONCed to the
321 ;;; beginning of the current value, rather than replacing it entirely.
322 (defun make-lexenv (&key (default *lexenv*)
323 functions variables blocks tags type-restrictions
325 (lambda (lexenv-lambda default))
326 (cleanup (lexenv-cleanup default))
327 (policy (lexenv-policy default)))
328 (macrolet ((frob (var slot)
329 `(let ((old (,slot default)))
333 (internal-make-lexenv
334 (frob functions lexenv-functions)
335 (frob variables lexenv-variables)
336 (frob blocks lexenv-blocks)
337 (frob tags lexenv-tags)
338 (frob type-restrictions lexenv-type-restrictions)
339 lambda cleanup policy
340 (frob options lexenv-options))))
342 ;;;; flow/DFO/component hackery
344 ;;; Join BLOCK1 and BLOCK2.
345 #!-sb-fluid (declaim (inline link-blocks))
346 (defun link-blocks (block1 block2)
347 (declare (type cblock block1 block2))
348 (setf (block-succ block1)
349 (if (block-succ block1)
350 (%link-blocks block1 block2)
352 (push block1 (block-pred block2))
354 (defun %link-blocks (block1 block2)
355 (declare (type cblock block1 block2) (inline member))
356 (let ((succ1 (block-succ block1)))
357 (aver (not (member block2 succ1 :test #'eq)))
358 (cons block2 succ1)))
360 ;;; Like LINK-BLOCKS, but we separate BLOCK1 and BLOCK2. If this leaves a
361 ;;; successor with a single predecessor that ends in an IF, then set
362 ;;; BLOCK-TEST-MODIFIED so that any test constraint will now be able to be
363 ;;; propagated to the successor.
364 (defun unlink-blocks (block1 block2)
365 (declare (type cblock block1 block2))
366 (let ((succ1 (block-succ block1)))
367 (if (eq block2 (car succ1))
368 (setf (block-succ block1) (cdr succ1))
369 (do ((succ (cdr succ1) (cdr succ))
371 ((eq (car succ) block2)
372 (setf (cdr prev) (cdr succ)))
375 (let ((new-pred (delq block1 (block-pred block2))))
376 (setf (block-pred block2) new-pred)
377 (when (and new-pred (null (rest new-pred)))
378 (let ((pred-block (first new-pred)))
379 (when (if-p (block-last pred-block))
380 (setf (block-test-modified pred-block) t)))))
383 ;;; Swing the succ/pred link between Block and Old to be between Block and
384 ;;; New. If Block ends in an IF, then we have to fix up the
385 ;;; consequent/alternative blocks to point to New. We also set
386 ;;; BLOCK-TEST-MODIFIED so that any test constraint will be applied to the new
388 (defun change-block-successor (block old new)
389 (declare (type cblock new old block) (inline member))
390 (unlink-blocks block old)
391 (let ((last (block-last block))
392 (comp (block-component block)))
393 (setf (component-reanalyze comp) t)
396 (setf (block-test-modified block) t)
397 (let* ((succ-left (block-succ block))
398 (new (if (and (eq new (component-tail comp))
402 (unless (member new succ-left :test #'eq)
403 (link-blocks block new))
404 (macrolet ((frob (slot)
405 `(when (eq (,slot last) old)
406 (setf (,slot last) new))))
408 (frob if-alternative))))
410 (unless (member new (block-succ block) :test #'eq)
411 (link-blocks block new)))))
415 ;;; Unlink a block from the next/prev chain. We also null out the
417 (declaim (ftype (function (cblock) (values)) remove-from-dfo))
418 #!-sb-fluid (declaim (inline remove-from-dfo))
419 (defun remove-from-dfo (block)
420 (let ((next (block-next block))
421 (prev (block-prev block)))
422 (setf (block-component block) nil)
423 (setf (block-next prev) next)
424 (setf (block-prev next) prev))
427 ;;; Add Block to the next/prev chain following After. We also set the
428 ;;; Component to be the same as for After.
429 #!-sb-fluid (declaim (inline add-to-dfo))
430 (defun add-to-dfo (block after)
431 (declare (type cblock block after))
432 (let ((next (block-next after))
433 (comp (block-component after)))
434 (aver (not (eq (component-kind comp) :deleted)))
435 (setf (block-component block) comp)
436 (setf (block-next after) block)
437 (setf (block-prev block) after)
438 (setf (block-next block) next)
439 (setf (block-prev next) block))
442 ;;; Set the Flag for all the blocks in Component to NIL, except for the head
443 ;;; and tail which are set to T.
444 (declaim (ftype (function (component) (values)) clear-flags))
445 (defun clear-flags (component)
446 (let ((head (component-head component))
447 (tail (component-tail component)))
448 (setf (block-flag head) t)
449 (setf (block-flag tail) t)
450 (do-blocks (block component)
451 (setf (block-flag block) nil)))
454 ;;; Make a component with no blocks in it. The Block-Flag is initially
455 ;;; true in the head and tail blocks.
456 (declaim (ftype (function nil component) make-empty-component))
457 (defun make-empty-component ()
458 (let* ((head (make-block-key :start nil :component nil))
459 (tail (make-block-key :start nil :component nil))
460 (res (make-component :head head :tail tail)))
461 (setf (block-flag head) t)
462 (setf (block-flag tail) t)
463 (setf (block-component head) res)
464 (setf (block-component tail) res)
465 (setf (block-next head) tail)
466 (setf (block-prev tail) head)
469 ;;; Makes Node the Last node in its block, splitting the block if necessary.
470 ;;; The new block is added to the DFO immediately following Node's block.
471 (defun node-ends-block (node)
472 (declare (type node node))
473 (let* ((block (node-block node))
474 (start (node-cont node))
475 (last (block-last block))
476 (last-cont (node-cont last)))
477 (unless (eq last node)
478 (aver (and (eq (continuation-kind start) :inside-block)
479 (not (block-delete-p block))))
480 (let* ((succ (block-succ block))
482 (make-block-key :start start
483 :component (block-component block)
484 :start-uses (list (continuation-use start))
485 :succ succ :last last)))
486 (setf (continuation-kind start) :block-start)
489 (cons new-block (remove block (block-pred b)))))
490 (setf (block-succ block) ())
491 (setf (block-last block) node)
492 (link-blocks block new-block)
493 (add-to-dfo new-block block)
494 (setf (component-reanalyze (block-component block)) t)
496 (do ((cont start (node-cont (continuation-next cont))))
498 (when (eq (continuation-kind last-cont) :inside-block)
499 (setf (continuation-block last-cont) new-block)))
500 (setf (continuation-block cont) new-block))
502 (setf (block-type-asserted block) t)
503 (setf (block-test-modified block) t))))
509 ;;; Deal with deleting the last (read) reference to a lambda-var. We
510 ;;; iterate over all local calls flushing the corresponding argument, allowing
511 ;;; the computation of the argument to be deleted. We also mark the let for
512 ;;; reoptimization, since it may be that we have deleted the last variable.
514 ;;; The lambda-var may still have some sets, but this doesn't cause too much
515 ;;; difficulty, since we can efficiently implement write-only variables. We
516 ;;; iterate over the sets, marking their blocks for dead code flushing, since
517 ;;; we can delete sets whose value is unused.
518 (defun delete-lambda-var (leaf)
519 (declare (type lambda-var leaf))
520 (let* ((fun (lambda-var-home leaf))
521 (n (position leaf (lambda-vars fun))))
522 (dolist (ref (leaf-refs fun))
523 (let* ((cont (node-cont ref))
524 (dest (continuation-dest cont)))
525 (when (and (combination-p dest)
526 (eq (basic-combination-fun dest) cont)
527 (eq (basic-combination-kind dest) :local))
528 (let* ((args (basic-combination-args dest))
530 (reoptimize-continuation arg)
532 (setf (elt args n) nil))))))
534 (dolist (set (lambda-var-sets leaf))
535 (setf (block-flush-p (node-block set)) t))
539 ;;; Note that something interesting has happened to Var. We only deal with
540 ;;; LET variables, marking the corresponding initial value arg as needing to be
542 (defun reoptimize-lambda-var (var)
543 (declare (type lambda-var var))
544 (let ((fun (lambda-var-home var)))
545 (when (and (eq (functional-kind fun) :let)
547 (do ((args (basic-combination-args
550 (first (leaf-refs fun)))))
552 (vars (lambda-vars fun) (cdr vars)))
554 (reoptimize-continuation (car args))))))
557 ;;; This function deletes functions that have no references. This need only
558 ;;; be called on functions that never had any references, since otherwise
559 ;;; DELETE-REF will handle the deletion.
560 (defun delete-functional (fun)
561 (aver (and (null (leaf-refs fun))
562 (not (functional-entry-function fun))))
564 (optional-dispatch (delete-optional-dispatch fun))
565 (clambda (delete-lambda fun)))
568 ;;; Deal with deleting the last reference to a lambda. Since there is only
569 ;;; one way into a lambda, deleting the last reference to a lambda ensures that
570 ;;; there is no way to reach any of the code in it. So we just set the
571 ;;; Functional-Kind for Fun and its Lets to :Deleted, causing IR1 optimization
572 ;;; to delete blocks in that lambda.
574 ;;; If the function isn't a Let, we unlink the function head and tail from
575 ;;; the component head and tail to indicate that the code is unreachable. We
576 ;;; also delete the function from Component-Lambdas (it won't be there before
577 ;;; local call analysis, but no matter.) If the lambda was never referenced,
580 ;;; If the lambda is an XEP, then we null out the Entry-Function in its
581 ;;; Entry-Function so that people will know that it is not an entry point
583 (defun delete-lambda (leaf)
584 (declare (type clambda leaf))
585 (let ((kind (functional-kind leaf))
586 (bind (lambda-bind leaf)))
587 (aver (not (member kind '(:deleted :optional :top-level))))
588 (setf (functional-kind leaf) :deleted)
589 (setf (lambda-bind leaf) nil)
590 (dolist (let (lambda-lets leaf))
591 (setf (lambda-bind let) nil)
592 (setf (functional-kind let) :deleted))
594 (if (member kind '(:let :mv-let :assignment))
595 (let ((home (lambda-home leaf)))
596 (setf (lambda-lets home) (delete leaf (lambda-lets home))))
597 (let* ((bind-block (node-block bind))
598 (component (block-component bind-block))
599 (return (lambda-return leaf)))
600 (aver (null (leaf-refs leaf)))
601 (unless (leaf-ever-used leaf)
602 (let ((*compiler-error-context* bind))
603 (compiler-note "deleting unused function~:[.~;~:*~% ~S~]"
605 (unlink-blocks (component-head component) bind-block)
607 (unlink-blocks (node-block return) (component-tail component)))
608 (setf (component-reanalyze component) t)
609 (let ((tails (lambda-tail-set leaf)))
610 (setf (tail-set-functions tails)
611 (delete leaf (tail-set-functions tails)))
612 (setf (lambda-tail-set leaf) nil))
613 (setf (component-lambdas component)
614 (delete leaf (component-lambdas component)))))
616 (when (eq kind :external)
617 (let ((fun (functional-entry-function leaf)))
618 (setf (functional-entry-function fun) nil)
619 (when (optional-dispatch-p fun)
620 (delete-optional-dispatch fun)))))
624 ;;; Deal with deleting the last reference to an Optional-Dispatch. We have
625 ;;; to be a bit more careful than with lambdas, since Delete-Ref is used both
626 ;;; before and after local call analysis. Afterward, all references to
627 ;;; still-existing optional-dispatches have been moved to the XEP, leaving it
628 ;;; with no references at all. So we look at the XEP to see whether an
629 ;;; optional-dispatch is still really being used. But before local call
630 ;;; analysis, there are no XEPs, and all references are direct.
632 ;;; When we do delete the optional-dispatch, we grovel all of its
633 ;;; entry-points, making them be normal lambdas, and then deleting the ones
634 ;;; with no references. This deletes any e-p lambdas that were either never
635 ;;; referenced, or couldn't be deleted when the last deference was deleted (due
636 ;;; to their :OPTIONAL kind.)
638 ;;; Note that the last optional ep may alias the main entry, so when we process
639 ;;; the main entry, its kind may have been changed to NIL or even converted to
641 (defun delete-optional-dispatch (leaf)
642 (declare (type optional-dispatch leaf))
643 (let ((entry (functional-entry-function leaf)))
644 (unless (and entry (leaf-refs entry))
645 (aver (or (not entry) (eq (functional-kind entry) :deleted)))
646 (setf (functional-kind leaf) :deleted)
649 (unless (eq (functional-kind fun) :deleted)
650 (aver (eq (functional-kind fun) :optional))
651 (setf (functional-kind fun) nil)
652 (let ((refs (leaf-refs fun)))
656 (or (maybe-let-convert fun)
657 (maybe-convert-to-assignment fun)))
659 (maybe-convert-to-assignment fun)))))))
661 (dolist (ep (optional-dispatch-entry-points leaf))
663 (when (optional-dispatch-more-entry leaf)
664 (frob (optional-dispatch-more-entry leaf)))
665 (let ((main (optional-dispatch-main-entry leaf)))
666 (when (eq (functional-kind main) :optional)
671 ;;; Do stuff to delete the semantic attachments of a Ref node. When this
672 ;;; leaves zero or one reference, we do a type dispatch off of the leaf to
673 ;;; determine if a special action is appropriate.
674 (defun delete-ref (ref)
675 (declare (type ref ref))
676 (let* ((leaf (ref-leaf ref))
677 (refs (delete ref (leaf-refs leaf))))
678 (setf (leaf-refs leaf) refs)
682 (lambda-var (delete-lambda-var leaf))
684 (ecase (functional-kind leaf)
685 ((nil :let :mv-let :assignment :escape :cleanup)
686 (aver (not (functional-entry-function leaf)))
687 (delete-lambda leaf))
689 (delete-lambda leaf))
690 ((:deleted :optional))))
692 (unless (eq (functional-kind leaf) :deleted)
693 (delete-optional-dispatch leaf)))))
696 (clambda (or (maybe-let-convert leaf)
697 (maybe-convert-to-assignment leaf)))
698 (lambda-var (reoptimize-lambda-var leaf))))
701 (clambda (maybe-convert-to-assignment leaf))))))
705 ;;; This function is called by people who delete nodes; it provides a way to
706 ;;; indicate that the value of a continuation is no longer used. We null out
707 ;;; the Continuation-Dest, set Flush-P in the blocks containing uses of Cont
708 ;;; and set Component-Reoptimize. If the Prev of the use is deleted, then we
709 ;;; blow off reoptimization.
711 ;;; If the continuation is :Deleted, then we don't do anything, since all
712 ;;; semantics have already been flushed. :Deleted-Block-Start start
713 ;;; continuations are treated just like :Block-Start; it is possible that the
714 ;;; continuation may be given a new dest (e.g. by SUBSTITUTE-CONTINUATION), so
715 ;;; we don't want to delete it.
716 (defun flush-dest (cont)
717 (declare (type continuation cont))
719 (unless (eq (continuation-kind cont) :deleted)
720 (aver (continuation-dest cont))
721 (setf (continuation-dest cont) nil)
723 (let ((prev (node-prev use)))
724 (unless (eq (continuation-kind prev) :deleted)
725 (let ((block (continuation-block prev)))
726 (setf (component-reoptimize (block-component block)) t)
727 (setf (block-attributep (block-flags block) flush-p type-asserted)
730 (setf (continuation-%type-check cont) nil)
734 ;;; Do a graph walk backward from Block, marking all predecessor blocks with
735 ;;; the DELETE-P flag.
736 (defun mark-for-deletion (block)
737 (declare (type cblock block))
738 (unless (block-delete-p block)
739 (setf (block-delete-p block) t)
740 (setf (component-reanalyze (block-component block)) t)
741 (dolist (pred (block-pred block))
742 (mark-for-deletion pred)))
745 ;;; Delete Cont, eliminating both control and value semantics. We set
746 ;;; FLUSH-P and COMPONENT-REOPTIMIZE similarly to in FLUSH-DEST. Here we must
747 ;;; get the component from the use block, since the continuation may be a
748 ;;; :DELETED-BLOCK-START.
750 ;;; If Cont has DEST, then it must be the case that the DEST is unreachable,
751 ;;; since we can't compute the value desired. In this case, we call
752 ;;; MARK-FOR-DELETION to cause the DEST block and its predecessors to tell
753 ;;; people to ignore them, and to cause them to be deleted eventually.
754 (defun delete-continuation (cont)
755 (declare (type continuation cont))
756 (aver (not (eq (continuation-kind cont) :deleted)))
759 (let ((prev (node-prev use)))
760 (unless (eq (continuation-kind prev) :deleted)
761 (let ((block (continuation-block prev)))
762 (setf (block-attributep (block-flags block) flush-p type-asserted) t)
763 (setf (component-reoptimize (block-component block)) t)))))
765 (let ((dest (continuation-dest cont)))
767 (let ((prev (node-prev dest)))
769 (not (eq (continuation-kind prev) :deleted)))
770 (let ((block (continuation-block prev)))
771 (unless (block-delete-p block)
772 (mark-for-deletion block)))))))
774 (setf (continuation-kind cont) :deleted)
775 (setf (continuation-dest cont) nil)
776 (setf (continuation-next cont) nil)
777 (setf (continuation-asserted-type cont) *empty-type*)
778 (setf (continuation-%derived-type cont) *empty-type*)
779 (setf (continuation-use cont) nil)
780 (setf (continuation-block cont) nil)
781 (setf (continuation-reoptimize cont) nil)
782 (setf (continuation-%type-check cont) nil)
783 (setf (continuation-info cont) nil)
787 ;;; This function does what is necessary to eliminate the code in it
788 ;;; from the IR1 representation. This involves unlinking it from its
789 ;;; predecessors and successors and deleting various node-specific
790 ;;; semantic information.
792 ;;; We mark the START as has having no next and remove the last node
793 ;;; from its CONT's uses. We also flush the DEST for all continuations
794 ;;; whose values are received by nodes in the block.
795 (defun delete-block (block)
796 (declare (type cblock block))
797 (aver (block-component block)) ; else block is already deleted!
798 (note-block-deletion block)
799 (setf (block-delete-p block) t)
801 (let* ((last (block-last block))
802 (cont (node-cont last)))
803 (delete-continuation-use last)
804 (if (eq (continuation-kind cont) :unused)
805 (delete-continuation cont)
806 (reoptimize-continuation cont)))
808 (dolist (b (block-pred block))
809 (unlink-blocks b block))
810 (dolist (b (block-succ block))
811 (unlink-blocks block b))
813 (do-nodes (node cont block)
815 (ref (delete-ref node))
817 (flush-dest (if-test node)))
818 ;; The next two cases serve to maintain the invariant that a LET always
819 ;; has a well-formed COMBINATION, REF and BIND. We delete the lambda
820 ;; whenever we delete any of these, but we must be careful that this LET
821 ;; has not already been partially deleted.
823 (when (and (eq (basic-combination-kind node) :local)
824 ;; Guards COMBINATION-LAMBDA agains the REF being deleted.
825 (continuation-use (basic-combination-fun node)))
826 (let ((fun (combination-lambda node)))
827 ;; If our REF was the 2'nd to last ref, and has been deleted, then
828 ;; Fun may be a LET for some other combination.
829 (when (and (member (functional-kind fun) '(:let :mv-let))
830 (eq (let-combination fun) node))
831 (delete-lambda fun))))
832 (flush-dest (basic-combination-fun node))
833 (dolist (arg (basic-combination-args node))
834 (when arg (flush-dest arg))))
836 (let ((lambda (bind-lambda node)))
837 (unless (eq (functional-kind lambda) :deleted)
838 (aver (member (functional-kind lambda) '(:let :mv-let :assignment)))
839 (delete-lambda lambda))))
841 (let ((value (exit-value node))
842 (entry (exit-entry node)))
846 (setf (entry-exits entry)
847 (delete node (entry-exits entry))))))
849 (flush-dest (return-result node))
850 (delete-return node))
852 (flush-dest (set-value node))
853 (let ((var (set-var node)))
854 (setf (basic-var-sets var)
855 (delete node (basic-var-sets var))))))
857 (delete-continuation (node-prev node)))
859 (remove-from-dfo block)
862 ;;; Do stuff to indicate that the return node Node is being deleted. We set
863 ;;; the RETURN to NIL.
864 (defun delete-return (node)
865 (declare (type creturn node))
866 (let ((fun (return-lambda node)))
867 (aver (lambda-return fun))
868 (setf (lambda-return fun) nil))
871 ;;; If any of the Vars in fun were never referenced and was not declared
872 ;;; IGNORE, then complain.
873 (defun note-unreferenced-vars (fun)
874 (declare (type clambda fun))
875 (dolist (var (lambda-vars fun))
876 (unless (or (leaf-ever-used var)
877 (lambda-var-ignorep var))
878 (let ((*compiler-error-context* (lambda-bind fun)))
879 (unless (policy *compiler-error-context* (= inhibit-warnings 3))
880 ;; ANSI section "3.2.5 Exceptional Situations in the Compiler"
881 ;; requires this to be a STYLE-WARNING.
882 (compiler-style-warning "The variable ~S is defined but never used."
884 (setf (leaf-ever-used var) t))))
887 (defvar *deletion-ignored-objects* '(t nil))
889 ;;; Return true if we can find Obj in Form, NIL otherwise. We bound our
890 ;;; recursion so that we don't get lost in circular structures. We ignore the
891 ;;; car of forms if they are a symbol (to prevent confusing function
892 ;;; referencess with variables), and we also ignore anything inside ' or #'.
893 (defun present-in-form (obj form depth)
894 (declare (type (integer 0 20) depth))
895 (cond ((= depth 20) nil)
899 (let ((first (car form))
901 (if (member first '(quote function))
903 (or (and (not (symbolp first))
904 (present-in-form obj first depth))
905 (do ((l (cdr form) (cdr l))
907 ((or (atom l) (> n 100))
910 (when (present-in-form obj (car l) depth)
913 ;;; This function is called on a block immediately before we delete it. We
914 ;;; check to see whether any of the code about to die appeared in the original
915 ;;; source, and emit a note if so.
917 ;;; If the block was in a lambda is now deleted, then we ignore the whole
918 ;;; block, since this case is picked off in DELETE-LAMBDA. We also ignore
919 ;;; the deletion of CRETURN nodes, since it is somewhat reasonable for a
920 ;;; function to not return, and there is a different note for that case anyway.
922 ;;; If the actual source is an atom, then we use a bunch of heuristics to
923 ;;; guess whether this reference really appeared in the original source:
924 ;;; -- If a symbol, it must be interned and not a keyword.
925 ;;; -- It must not be an easily introduced constant (T or NIL, a fixnum or a
927 ;;; -- The atom must be "present" in the original source form, and present in
928 ;;; all intervening actual source forms.
929 (defun note-block-deletion (block)
930 (let ((home (block-home-lambda block)))
931 (unless (eq (functional-kind home) :deleted)
932 (do-nodes (node cont block)
933 (let* ((path (node-source-path node))
934 (first (first path)))
935 (when (or (eq first 'original-source-start)
937 (or (not (symbolp first))
938 (let ((pkg (symbol-package first)))
940 (not (eq pkg (symbol-package :end))))))
941 (not (member first *deletion-ignored-objects*))
942 (not (typep first '(or fixnum character)))
944 (present-in-form first x 0))
945 (source-path-forms path))
946 (present-in-form first (find-original-source path)
948 (unless (return-p node)
949 (let ((*compiler-error-context* node))
950 (compiler-note "deleting unreachable code")))
954 ;;; Delete a node from a block, deleting the block if there are no nodes
955 ;;; left. We remove the node from the uses of its CONT, but we don't deal with
956 ;;; cleaning up any type-specific semantic attachments. If the CONT is :UNUSED
957 ;;; after deleting this use, then we delete CONT. (Note :UNUSED is not the
958 ;;; same as no uses. A continuation will only become :UNUSED if it was
959 ;;; :INSIDE-BLOCK before.)
961 ;;; If the node is the last node, there must be exactly one successor. We
962 ;;; link all of our precedessors to the successor and unlink the block. In
963 ;;; this case, we return T, otherwise NIL. If no nodes are left, and the block
964 ;;; is a successor of itself, then we replace the only node with a degenerate
965 ;;; exit node. This provides a way to represent the bodyless infinite loop,
966 ;;; given the prohibition on empty blocks in IR1.
967 (defun unlink-node (node)
968 (declare (type node node))
969 (let* ((cont (node-cont node))
970 (next (continuation-next cont))
971 (prev (node-prev node))
972 (block (continuation-block prev))
973 (prev-kind (continuation-kind prev))
974 (last (block-last block)))
976 (unless (eq (continuation-kind cont) :deleted)
977 (delete-continuation-use node)
978 (when (eq (continuation-kind cont) :unused)
979 (aver (not (continuation-dest cont)))
980 (delete-continuation cont)))
982 (setf (block-type-asserted block) t)
983 (setf (block-test-modified block) t)
985 (cond ((or (eq prev-kind :inside-block)
986 (and (eq prev-kind :block-start)
987 (not (eq node last))))
988 (cond ((eq node last)
989 (setf (block-last block) (continuation-use prev))
990 (setf (continuation-next prev) nil))
992 (setf (continuation-next prev) next)
993 (setf (node-prev next) prev)))
994 (setf (node-prev node) nil)
997 (aver (eq prev-kind :block-start))
998 (aver (eq node last))
999 (let* ((succ (block-succ block))
1000 (next (first succ)))
1001 (aver (and succ (null (cdr succ))))
1003 ((member block succ)
1004 (with-ir1-environment node
1005 (let ((exit (make-exit))
1006 (dummy (make-continuation)))
1007 (setf (continuation-next prev) nil)
1008 (prev-link exit prev)
1009 (add-continuation-use exit dummy)
1010 (setf (block-last block) exit)))
1011 (setf (node-prev node) nil)
1014 (aver (eq (block-start-cleanup block)
1015 (block-end-cleanup block)))
1016 (unlink-blocks block next)
1017 (dolist (pred (block-pred block))
1018 (change-block-successor pred block next))
1019 (remove-from-dfo block)
1020 (cond ((continuation-dest prev)
1021 (setf (continuation-next prev) nil)
1022 (setf (continuation-kind prev) :deleted-block-start))
1024 (delete-continuation prev)))
1025 (setf (node-prev node) nil)
1028 ;;; Return true if NODE has been deleted, false if it is still a valid part
1030 (defun node-deleted (node)
1031 (declare (type node node))
1032 (let ((prev (node-prev node)))
1034 (not (eq (continuation-kind prev) :deleted))
1035 (let ((block (continuation-block prev)))
1036 (and (block-component block)
1037 (not (block-delete-p block))))))))
1039 ;;; Delete all the blocks and functions in Component. We scan first marking
1040 ;;; the blocks as delete-p to prevent weird stuff from being triggered by
1042 (defun delete-component (component)
1043 (declare (type component component))
1044 (aver (null (component-new-functions component)))
1045 (setf (component-kind component) :deleted)
1046 (do-blocks (block component)
1047 (setf (block-delete-p block) t))
1048 (dolist (fun (component-lambdas component))
1049 (setf (functional-kind fun) nil)
1050 (setf (functional-entry-function fun) nil)
1051 (setf (leaf-refs fun) nil)
1052 (delete-functional fun))
1053 (do-blocks (block component)
1054 (delete-block block))
1057 ;;; Convert code of the form
1058 ;;; (FOO ... (FUN ...) ...)
1060 ;;; (FOO ... ... ...).
1061 ;;; In other words, replace the function combination FUN by its
1062 ;;; arguments. If there are any problems with doing this, use GIVE-UP
1063 ;;; to blow out of whatever transform called this. Note, as the number
1064 ;;; of arguments changes, the transform must be prepared to return a
1065 ;;; lambda with a new lambda-list with the correct number of
1067 (defun extract-function-args (cont fun num-args)
1069 "If CONT is a call to FUN with NUM-ARGS args, change those arguments
1070 to feed directly to the continuation-dest of CONT, which must be
1072 (declare (type continuation cont)
1074 (type index num-args))
1075 (let ((outside (continuation-dest cont))
1076 (inside (continuation-use cont)))
1077 (aver (combination-p outside))
1078 (unless (combination-p inside)
1079 (give-up-ir1-transform))
1080 (let ((inside-fun (combination-fun inside)))
1081 (unless (eq (continuation-function-name inside-fun) fun)
1082 (give-up-ir1-transform))
1083 (let ((inside-args (combination-args inside)))
1084 (unless (= (length inside-args) num-args)
1085 (give-up-ir1-transform))
1086 (let* ((outside-args (combination-args outside))
1087 (arg-position (position cont outside-args))
1088 (before-args (subseq outside-args 0 arg-position))
1089 (after-args (subseq outside-args (1+ arg-position))))
1090 (dolist (arg inside-args)
1091 (setf (continuation-dest arg) outside))
1092 (setf (combination-args inside) nil)
1093 (setf (combination-args outside)
1094 (append before-args inside-args after-args))
1095 (change-ref-leaf (continuation-use inside-fun)
1096 (find-free-function 'list "???"))
1097 (setf (combination-kind inside) :full)
1098 (setf (node-derived-type inside) *wild-type*)
1100 (setf (continuation-asserted-type cont) *wild-type*)
1105 ;;; Change the Leaf that a Ref refers to.
1106 (defun change-ref-leaf (ref leaf)
1107 (declare (type ref ref) (type leaf leaf))
1108 (unless (eq (ref-leaf ref) leaf)
1109 (push ref (leaf-refs leaf))
1111 (setf (ref-leaf ref) leaf)
1112 (let ((ltype (leaf-type leaf)))
1113 (if (function-type-p ltype)
1114 (setf (node-derived-type ref) ltype)
1115 (derive-node-type ref ltype)))
1116 (reoptimize-continuation (node-cont ref)))
1119 ;;; Change all Refs for Old-Leaf to New-Leaf.
1120 (defun substitute-leaf (new-leaf old-leaf)
1121 (declare (type leaf new-leaf old-leaf))
1122 (dolist (ref (leaf-refs old-leaf))
1123 (change-ref-leaf ref new-leaf))
1126 ;;; Like SUBSITIUTE-LEAF, only there is a predicate on the Ref to tell
1127 ;;; whether to substitute.
1128 (defun substitute-leaf-if (test new-leaf old-leaf)
1129 (declare (type leaf new-leaf old-leaf) (type function test))
1130 (dolist (ref (leaf-refs old-leaf))
1131 (when (funcall test ref)
1132 (change-ref-leaf ref new-leaf)))
1135 ;;; Return a LEAF which represents the specified constant object. If the
1136 ;;; object is not in *CONSTANTS*, then we create a new constant LEAF and
1138 #!-sb-fluid (declaim (maybe-inline find-constant))
1139 (defun find-constant (object)
1140 (if (typep object '(or symbol number character instance))
1141 (or (gethash object *constants*)
1142 (setf (gethash object *constants*)
1143 (make-constant :value object
1145 :type (ctype-of object)
1146 :where-from :defined)))
1147 (make-constant :value object
1149 :type (ctype-of object)
1150 :where-from :defined)))
1152 ;;; If there is a non-local exit noted in Entry's environment that exits to
1153 ;;; Cont in that entry, then return it, otherwise return NIL.
1154 (defun find-nlx-info (entry cont)
1155 (declare (type entry entry) (type continuation cont))
1156 (let ((entry-cleanup (entry-cleanup entry)))
1157 (dolist (nlx (environment-nlx-info (node-environment entry)) nil)
1158 (when (and (eq (nlx-info-continuation nlx) cont)
1159 (eq (nlx-info-cleanup nlx) entry-cleanup))
1162 ;;;; functional hackery
1164 ;;; If Functional is a Lambda, just return it; if it is an
1165 ;;; optional-dispatch, return the main-entry.
1166 (declaim (ftype (function (functional) clambda) main-entry))
1167 (defun main-entry (functional)
1168 (etypecase functional
1169 (clambda functional)
1171 (optional-dispatch-main-entry functional))))
1173 ;;; Returns true if Functional is a thing that can be treated like
1174 ;;; MV-Bind when it appears in an MV-Call. All fixed arguments must be
1175 ;;; optional with null default and no supplied-p. There must be a rest
1176 ;;; arg with no references.
1177 (declaim (ftype (function (functional) boolean) looks-like-an-mv-bind))
1178 (defun looks-like-an-mv-bind (functional)
1179 (and (optional-dispatch-p functional)
1180 (do ((arg (optional-dispatch-arglist functional) (cdr arg)))
1182 (let ((info (lambda-var-arg-info (car arg))))
1183 (unless info (return nil))
1184 (case (arg-info-kind info)
1186 (when (or (arg-info-supplied-p info) (arg-info-default info))
1189 (return (and (null (cdr arg)) (null (leaf-refs (car arg))))))
1193 ;;; Return true if function is an XEP. This is true of normal XEPs
1194 ;;; (:External kind) and top-level lambdas (:Top-Level kind.)
1195 #!-sb-fluid (declaim (inline external-entry-point-p))
1196 (defun external-entry-point-p (fun)
1197 (declare (type functional fun))
1198 (not (null (member (functional-kind fun) '(:external :top-level)))))
1200 ;;; If Cont's only use is a non-notinline global function reference, then
1201 ;;; return the referenced symbol, otherwise NIL. If Notinline-OK is true, then
1202 ;;; we don't care if the leaf is notinline.
1203 (defun continuation-function-name (cont &optional notinline-ok)
1204 (declare (type continuation cont))
1205 (let ((use (continuation-use cont)))
1207 (let ((leaf (ref-leaf use)))
1208 (if (and (global-var-p leaf)
1209 (eq (global-var-kind leaf) :global-function)
1210 (or (not (defined-function-p leaf))
1211 (not (eq (defined-function-inlinep leaf) :notinline))
1217 ;;; Return the COMBINATION node that is the call to the let Fun.
1218 (defun let-combination (fun)
1219 (declare (type clambda fun))
1220 (aver (member (functional-kind fun) '(:let :mv-let)))
1221 (continuation-dest (node-cont (first (leaf-refs fun)))))
1223 ;;; Return the initial value continuation for a let variable or NIL if none.
1224 (defun let-var-initial-value (var)
1225 (declare (type lambda-var var))
1226 (let ((fun (lambda-var-home var)))
1227 (elt (combination-args (let-combination fun))
1228 (position-or-lose var (lambda-vars fun)))))
1230 ;;; Return the LAMBDA that is called by the local Call.
1231 #!-sb-fluid (declaim (inline combination-lambda))
1232 (defun combination-lambda (call)
1233 (declare (type basic-combination call))
1234 (aver (eq (basic-combination-kind call) :local))
1235 (ref-leaf (continuation-use (basic-combination-fun call))))
1237 (defvar *inline-expansion-limit* 200
1239 "An upper limit on the number of inline function calls that will be expanded
1240 in any given code object (single function or block compilation.)")
1242 ;;; Check whether Node's component has exceeded its inline expansion
1243 ;;; limit, and warn if so, returning NIL.
1244 (defun inline-expansion-ok (node)
1245 (let ((expanded (incf (component-inline-expansions
1247 (node-block node))))))
1248 (cond ((> expanded *inline-expansion-limit*) nil)
1249 ((= expanded *inline-expansion-limit*)
1250 (let ((*compiler-error-context* node))
1251 (compiler-note "*INLINE-EXPANSION-LIMIT* (~D) was exceeded, ~
1252 probably trying to~% ~
1253 inline a recursive function."
1254 *inline-expansion-limit*))
1258 ;;;; compiler error context determination
1260 (declaim (special *current-path*))
1262 ;;; We bind print level and length when printing out messages so that
1263 ;;; we don't dump huge amounts of garbage.
1265 ;;; FIXME: It's not possible to get the defaults right for everyone.
1266 ;;; So: Should these variables be in the SB-EXT package? Or should we
1267 ;;; just get rid of them completely and just use the bare
1268 ;;; CL:*PRINT-FOO* variables instead?
1269 (declaim (type (or unsigned-byte null)
1270 *compiler-error-print-level*
1271 *compiler-error-print-length*
1272 *compiler-error-print-lines*))
1273 (defvar *compiler-error-print-level* 5
1275 "the value for *PRINT-LEVEL* when printing compiler error messages")
1276 (defvar *compiler-error-print-length* 10
1278 "the value for *PRINT-LENGTH* when printing compiler error messages")
1279 (defvar *compiler-error-print-lines* 12
1281 "the value for *PRINT-LINES* when printing compiler error messages")
1283 (defvar *enclosing-source-cutoff* 1
1285 "The maximum number of enclosing non-original source forms (i.e. from
1286 macroexpansion) that we print in full. For additional enclosing forms, we
1287 print only the CAR.")
1288 (declaim (type unsigned-byte *enclosing-source-cutoff*))
1290 ;;; We separate the determination of compiler error contexts from the
1291 ;;; actual signalling of those errors by objectifying the error
1292 ;;; context. This allows postponement of the determination of how (and
1293 ;;; if) to signal the error.
1295 ;;; We take care not to reference any of the IR1 so that pending
1296 ;;; potential error messages won't prevent the IR1 from being GC'd. To
1297 ;;; this end, we convert source forms to strings so that source forms
1298 ;;; that contain IR1 references (e.g. %DEFUN) don't hold onto the IR.
1299 (defstruct (compiler-error-context
1300 #-no-ansi-print-object
1301 (:print-object (lambda (x stream)
1302 (print-unreadable-object (x stream :type t))))
1304 ;; A list of the stringified CARs of the enclosing non-original source forms
1305 ;; exceeding the *enclosing-source-cutoff*.
1306 (enclosing-source nil :type list)
1307 ;; A list of stringified enclosing non-original source forms.
1308 (source nil :type list)
1309 ;; The stringified form in the original source that expanded into Source.
1310 (original-source (required-argument) :type simple-string)
1311 ;; A list of prefixes of "interesting" forms that enclose original-source.
1312 (context nil :type list)
1313 ;; The FILE-INFO-NAME for the relevant FILE-INFO.
1314 (file-name (required-argument)
1315 :type (or pathname (member :lisp :stream)))
1316 ;; The file position at which the top-level form starts, if applicable.
1317 (file-position nil :type (or index null))
1318 ;; The original source part of the source path.
1319 (original-source-path nil :type list))
1321 ;;; If true, this is the node which is used as context in compiler warning
1323 (declaim (type (or null compiler-error-context node) *compiler-error-context*))
1324 (defvar *compiler-error-context* nil)
1326 ;;; a hashtable mapping macro names to source context parsers. Each parser
1327 ;;; function returns the source-context list for that form.
1328 (defvar *source-context-methods* (make-hash-table))
1330 ;;; documentation originally from cmu-user.tex:
1331 ;;; This macro defines how to extract an abbreviated source context from
1332 ;;; the \var{name}d form when it appears in the compiler input.
1333 ;;; \var{lambda-list} is a \code{defmacro} style lambda-list used to
1334 ;;; parse the arguments. The \var{body} should return a list of
1335 ;;; subforms that can be printed on about one line. There are
1336 ;;; predefined methods for \code{defstruct}, \code{defmethod}, etc. If
1337 ;;; no method is defined, then the first two subforms are returned.
1338 ;;; Note that this facility implicitly determines the string name
1339 ;;; associated with anonymous functions.
1340 ;;; So even though SBCL itself only uses this macro within this file,
1341 ;;; it's a reasonable thing to put in SB-EXT in case some dedicated
1342 ;;; user wants to do some heavy tweaking to make SBCL give more
1343 ;;; informative output about his code.
1344 (defmacro def-source-context (name lambda-list &body body)
1346 "DEF-SOURCE-CONTEXT Name Lambda-List Form*
1347 This macro defines how to extract an abbreviated source context from the
1348 Named form when it appears in the compiler input. Lambda-List is a DEFMACRO
1349 style lambda-list used to parse the arguments. The Body should return a
1350 list of subforms suitable for a \"~{~S ~}\" format string."
1351 (let ((n-whole (gensym)))
1352 `(setf (gethash ',name *source-context-methods*)
1353 #'(lambda (,n-whole)
1354 (destructuring-bind ,lambda-list ,n-whole ,@body)))))
1356 (def-source-context defstruct (name-or-options &rest slots)
1357 (declare (ignore slots))
1358 `(defstruct ,(if (consp name-or-options)
1359 (car name-or-options)
1362 (def-source-context function (thing)
1363 (if (and (consp thing) (eq (first thing) 'lambda) (consp (rest thing)))
1364 `(lambda ,(second thing))
1365 `(function ,thing)))
1367 ;;; Return the first two elements of FORM if FORM is a list. Take the
1368 ;;; CAR of the second form if appropriate.
1369 (defun source-form-context (form)
1370 (cond ((atom form) nil)
1371 ((>= (length form) 2)
1372 (funcall (gethash (first form) *source-context-methods*
1374 (declare (ignore x))
1375 (list (first form) (second form))))
1380 ;;; Given a source path, return the original source form and a
1381 ;;; description of the interesting aspects of the context in which it
1382 ;;; appeared. The context is a list of lists, one sublist per context
1383 ;;; form. The sublist is a list of some of the initial subforms of the
1386 ;;; For now, we use the first two subforms of each interesting form. A
1387 ;;; form is interesting if the first element is a symbol beginning
1388 ;;; with "DEF" and it is not the source form. If there is no
1389 ;;; DEF-mumble, then we use the outermost containing form. If the
1390 ;;; second subform is a list, then in some cases we return the CAR of
1391 ;;; that form rather than the whole form (i.e. don't show DEFSTRUCT
1393 (defun find-original-source (path)
1394 (declare (list path))
1395 (let* ((rpath (reverse (source-path-original-source path)))
1397 (root (find-source-root tlf *source-info*)))
1398 (collect ((context))
1400 (current (rest rpath)))
1403 (aver (null current))
1405 (let ((head (first form)))
1406 (when (symbolp head)
1407 (let ((name (symbol-name head)))
1408 (when (and (>= (length name) 3) (string= name "DEF" :end1 3))
1409 (context (source-form-context form))))))
1410 (when (null current) (return))
1411 (setq form (nth (pop current) form)))
1414 (values form (context)))
1416 (let ((c (source-form-context root)))
1417 (values form (if c (list c) nil))))
1419 (values '(unable to locate source)
1420 '((some strange place)))))))))
1422 ;;; Convert a source form to a string, suitably formatted for use in
1423 ;;; compiler warnings.
1424 (defun stringify-form (form &optional (pretty t))
1425 (let ((*print-level* *compiler-error-print-level*)
1426 (*print-length* *compiler-error-print-length*)
1427 (*print-lines* *compiler-error-print-lines*)
1428 (*print-pretty* pretty))
1430 (format nil "~<~@; ~S~:>" (list form))
1431 (prin1-to-string form))))
1433 ;;; Return a COMPILER-ERROR-CONTEXT structure describing the current
1434 ;;; error context, or NIL if we can't figure anything out. ARGS is a
1435 ;;; list of things that are going to be printed out in the error
1436 ;;; message, and can thus be blown off when they appear in the source
1438 (defun find-error-context (args)
1439 (let ((context *compiler-error-context*))
1440 (if (compiler-error-context-p context)
1442 (let ((path (or *current-path*
1444 (node-source-path context)
1446 (when (and *source-info* path)
1447 (multiple-value-bind (form src-context) (find-original-source path)
1448 (collect ((full nil cons)
1450 (let ((forms (source-path-forms path))
1452 (dolist (src (if (member (first forms) args)
1455 (if (>= n *enclosing-source-cutoff*)
1456 (short (stringify-form (if (consp src)
1460 (full (stringify-form src)))
1463 (let* ((tlf (source-path-tlf-number path))
1464 (file-info (source-info-file-info *source-info*)))
1465 (make-compiler-error-context
1466 :enclosing-source (short)
1468 :original-source (stringify-form form)
1469 :context src-context
1470 :file-name (file-info-name file-info)
1472 (multiple-value-bind (ignore pos)
1473 (find-source-root tlf *source-info*)
1474 (declare (ignore ignore))
1476 :original-source-path
1477 (source-path-original-source path))))))))))
1479 ;;;; printing error messages
1481 ;;; We save the context information that we printed out most recently
1482 ;;; so that we don't print it out redundantly.
1484 ;;; The last COMPILER-ERROR-CONTEXT that we printed.
1485 (defvar *last-error-context* nil)
1486 (declaim (type (or compiler-error-context null) *last-error-context*))
1488 ;;; The format string and args for the last error we printed.
1489 (defvar *last-format-string* nil)
1490 (defvar *last-format-args* nil)
1491 (declaim (type (or string null) *last-format-string*))
1492 (declaim (type list *last-format-args*))
1494 ;;; The number of times that the last error message has been emitted,
1495 ;;; so that we can compress duplicate error messages.
1496 (defvar *last-message-count* 0)
1497 (declaim (type index *last-message-count*))
1499 ;;; If the last message was given more than once, then print out an
1500 ;;; indication of how many times it was repeated. We reset the message count
1501 ;;; when we are done.
1502 (defun note-message-repeats (&optional (terpri t))
1503 (cond ((= *last-message-count* 1)
1504 (when terpri (terpri *error-output*)))
1505 ((> *last-message-count* 1)
1506 (format *error-output* "~&; [Last message occurs ~D times.]~2%"
1507 *last-message-count*)))
1508 (setq *last-message-count* 0))
1510 ;;; Print out the message, with appropriate context if we can find it.
1511 ;;; If the context is different from the context of the last message
1512 ;;; we printed, then we print the context. If the original source is
1513 ;;; different from the source we are working on, then we print the
1514 ;;; current source in addition to the original source.
1516 ;;; We suppress printing of messages identical to the previous, but
1517 ;;; record the number of times that the message is repeated.
1518 (defun print-compiler-message (format-string format-args)
1520 (declare (type simple-string format-string))
1521 (declare (type list format-args))
1523 (let ((stream *error-output*)
1524 (context (find-error-context format-args)))
1527 (let ((file (compiler-error-context-file-name context))
1528 (in (compiler-error-context-context context))
1529 (form (compiler-error-context-original-source context))
1530 (enclosing (compiler-error-context-enclosing-source context))
1531 (source (compiler-error-context-source context))
1532 (last *last-error-context*))
1535 (equal file (compiler-error-context-file-name last)))
1536 (when (pathnamep file)
1537 (note-message-repeats)
1539 (format stream "~2&; file: ~A~%" (namestring file))))
1542 (equal in (compiler-error-context-context last)))
1543 (note-message-repeats)
1545 (format stream "~&")
1546 (pprint-logical-block (stream nil :per-line-prefix "; ")
1547 (format stream "in:~{~<~% ~4:;~{ ~S~}~>~^ =>~}" in))
1548 (format stream "~%"))
1553 (compiler-error-context-original-source last)))
1554 (note-message-repeats)
1556 (format stream "~&")
1557 (pprint-logical-block (stream nil :per-line-prefix "; ")
1558 (format stream " ~A" form))
1559 (format stream "~&"))
1563 (compiler-error-context-enclosing-source last)))
1565 (note-message-repeats)
1567 (format stream "~&; --> ~{~<~%; --> ~1:;~A~> ~}~%" enclosing)))
1570 (equal source (compiler-error-context-source last)))
1571 (setq *last-format-string* nil)
1573 (note-message-repeats)
1574 (dolist (src source)
1575 (format stream "~&")
1576 (write-string "; ==>" stream)
1577 (format stream "~&")
1578 (pprint-logical-block (stream nil :per-line-prefix "; ")
1579 (write-string src stream)))))))
1581 (format stream "~&")
1582 (note-message-repeats)
1583 (setq *last-format-string* nil)
1584 (format stream "~&")))
1586 (setq *last-error-context* context)
1588 (unless (and (equal format-string *last-format-string*)
1589 (tree-equal format-args *last-format-args*))
1590 (note-message-repeats nil)
1591 (setq *last-format-string* format-string)
1592 (setq *last-format-args* format-args)
1593 (let ((*print-level* *compiler-error-print-level*)
1594 (*print-length* *compiler-error-print-length*)
1595 (*print-lines* *compiler-error-print-lines*))
1596 (format stream "~&")
1597 (pprint-logical-block (stream nil :per-line-prefix "; ")
1598 (format stream "~&~?" format-string format-args))
1599 (format stream "~&"))))
1601 (incf *last-message-count*)
1604 (defun print-compiler-condition (condition)
1605 (declare (type condition condition))
1606 (let (;; These different classes of conditions have different
1607 ;; effects on the return codes of COMPILE-FILE, so it's nice
1608 ;; for users to be able to pick them out by lexical search
1609 ;; through the output.
1610 (what (etypecase condition
1611 (style-warning 'style-warning)
1614 (multiple-value-bind (format-string format-args)
1615 (if (typep condition 'simple-condition)
1616 (values (simple-condition-format-control condition)
1617 (simple-condition-format-arguments condition))
1619 (list (with-output-to-string (s)
1620 (princ condition s)))))
1621 (print-compiler-message (format nil
1628 ;;; COMPILER-NOTE is vaguely like COMPILER-ERROR and the other
1629 ;;; condition-signalling functions, but it just writes some output
1630 ;;; instead of signalling. (In CMU CL, it did signal a condition, but
1631 ;;; this didn't seem to work all that well; it was weird to have
1632 ;;; COMPILE-FILE return with WARNINGS-P set when the only problem was
1633 ;;; that the compiler couldn't figure out how to compile something as
1634 ;;; efficiently as it liked.)
1635 (defun compiler-note (format-string &rest format-args)
1636 (unless (if *compiler-error-context*
1637 (policy *compiler-error-context* (= inhibit-warnings 3))
1638 (policy *lexenv* (= inhibit-warnings 3)))
1639 (incf *compiler-note-count*)
1640 (print-compiler-message (format nil "note: ~A" format-string)
1644 ;;; Issue a note when we might or might not be in the compiler.
1645 (defun maybe-compiler-note (&rest rest)
1646 (if (boundp '*lexenv*) ; if we're in the compiler
1647 (apply #'compiler-note rest)
1648 (let ((stream *error-output*))
1649 (pprint-logical-block (stream nil :per-line-prefix ";")
1651 (format stream " note: ~3I~_")
1652 (pprint-logical-block (stream nil)
1653 (apply #'format stream rest)))
1654 (fresh-line stream)))) ; (outside logical block, no per-line-prefix)
1656 ;;; The politically correct way to print out progress messages and
1657 ;;; such like. We clear the current error context so that we know that
1658 ;;; it needs to be reprinted, and we also Force-Output so that the
1659 ;;; message gets seen right away.
1660 (declaim (ftype (function (string &rest t) (values)) compiler-mumble))
1661 (defun compiler-mumble (format-string &rest format-args)
1662 (note-message-repeats)
1663 (setq *last-error-context* nil)
1664 (apply #'format *error-output* format-string format-args)
1665 (force-output *error-output*)
1668 ;;; Return a string that somehow names the code in COMPONENT. We use
1669 ;;; the source path for the bind node for an arbitrary entry point to
1670 ;;; find the source context, then return that as a string.
1671 (declaim (ftype (function (component) simple-string) find-component-name))
1672 (defun find-component-name (component)
1673 (let ((ep (first (block-succ (component-head component)))))
1674 (aver ep) ; else no entry points??
1675 (multiple-value-bind (form context)
1676 (find-original-source
1677 (node-source-path (continuation-next (block-start ep))))
1678 (declare (ignore form))
1679 (let ((*print-level* 2)
1680 (*print-pretty* nil))
1681 (format nil "~{~{~S~^ ~}~^ => ~}" context)))))
1683 ;;;; condition system interface
1685 ;;; Keep track of how many times each kind of condition happens.
1686 (defvar *compiler-error-count*)
1687 (defvar *compiler-warning-count*)
1688 (defvar *compiler-style-warning-count*)
1689 (defvar *compiler-note-count*)
1691 ;;; Keep track of whether any surrounding COMPILE or COMPILE-FILE call
1692 ;;; should return WARNINGS-P or FAILURE-P.
1693 (defvar *failure-p*)
1694 (defvar *warnings-p*)
1696 ;;; condition handlers established by the compiler. We re-signal the
1697 ;;; condition, then if it isn't handled, we increment our warning
1698 ;;; counter and print the error message.
1699 (defun compiler-error-handler (condition)
1701 (incf *compiler-error-count*)
1702 (setf *warnings-p* t
1704 (print-compiler-condition condition)
1705 (continue condition))
1706 (defun compiler-warning-handler (condition)
1708 (incf *compiler-warning-count*)
1709 (setf *warnings-p* t
1711 (print-compiler-condition condition)
1712 (muffle-warning condition))
1713 (defun compiler-style-warning-handler (condition)
1715 (incf *compiler-style-warning-count*)
1716 (setf *warnings-p* t)
1717 (print-compiler-condition condition)
1718 (muffle-warning condition))
1720 ;;;; undefined warnings
1722 (defvar *undefined-warning-limit* 3
1724 "If non-null, then an upper limit on the number of unknown function or type
1725 warnings that the compiler will print for any given name in a single
1726 compilation. This prevents excessive amounts of output when the real
1727 problem is a missing definition (as opposed to a typo in the use.)")
1729 ;;; Make an entry in the *UNDEFINED-WARNINGS* describing a reference
1730 ;;; to NAME of the specified KIND. If we have exceeded the warning
1731 ;;; limit, then just increment the count, otherwise note the current
1734 ;;; Undefined types are noted by a condition handler in
1735 ;;; WITH-COMPILATION-UNIT, which can potentially be invoked outside
1736 ;;; the compiler, hence the BOUNDP check.
1737 (defun note-undefined-reference (name kind)
1739 ;; Check for boundness so we don't blow up if we're called
1740 ;; when IR1 conversion isn't going on.
1742 ;; FIXME: I'm pretty sure the INHIBIT-WARNINGS test below
1743 ;; isn't a good idea; we should have INHIBIT-WARNINGS
1744 ;; affect compiler notes, not STYLE-WARNINGs. And I'm not
1745 ;; sure what the BOUNDP '*LEXENV* test above is for; it's
1746 ;; likely a good idea, but it probably deserves an
1747 ;; explanatory comment.
1748 (policy *lexenv* (= inhibit-warnings 3)))
1749 (let* ((found (dolist (warning *undefined-warnings* nil)
1750 (when (and (equal (undefined-warning-name warning) name)
1751 (eq (undefined-warning-kind warning) kind))
1754 (make-undefined-warning :name name :kind kind))))
1755 (unless found (push res *undefined-warnings*))
1756 (when (or (not *undefined-warning-limit*)
1757 (< (undefined-warning-count res) *undefined-warning-limit*))
1758 (push (find-error-context (list name))
1759 (undefined-warning-warnings res)))
1760 (incf (undefined-warning-count res))))
1765 ;;; Apply a function to some arguments, returning a list of the values
1766 ;;; resulting of the evaluation. If an error is signalled during the
1767 ;;; application, then we print a warning message and return NIL as our
1768 ;;; second value to indicate this. Node is used as the error context
1769 ;;; for any error message, and Context is a string that is spliced
1770 ;;; into the warning.
1771 (declaim (ftype (function ((or symbol function) list node string)
1772 (values list boolean))
1774 (defun careful-call (function args node context)
1776 (multiple-value-list
1777 (handler-case (apply function args)
1779 (let ((*compiler-error-context* node))
1780 (compiler-warning "Lisp error during ~A:~%~A" context condition)
1781 (return-from careful-call (values nil nil))))))
1784 ;;;; utilities used at run-time for parsing &KEY args in IR1
1786 ;;; This function is used by the result of PARSE-DEFTRANSFORM to find
1787 ;;; the continuation for the value of the &KEY argument KEY in the
1788 ;;; list of continuations ARGS. It returns the continuation if the
1789 ;;; keyword is present, or NIL otherwise. The legality and
1790 ;;; constantness of the keywords should already have been checked.
1791 (declaim (ftype (function (list keyword) (or continuation null))
1792 find-keyword-continuation))
1793 (defun find-keyword-continuation (args key)
1794 (do ((arg args (cddr arg)))
1796 (when (eq (continuation-value (first arg)) key)
1797 (return (second arg)))))
1799 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
1800 ;;; verify that alternating continuations in ARGS are constant and
1801 ;;; that there is an even number of args.
1802 (declaim (ftype (function (list) boolean) check-key-args-constant))
1803 (defun check-key-args-constant (args)
1804 (do ((arg args (cddr arg)))
1806 (unless (and (rest arg)
1807 (constant-continuation-p (first arg)))
1810 ;;; This function is used by the result of PARSE-DEFTRANSFORM to
1811 ;;; verify that the list of continuations ARGS is a well-formed &KEY
1812 ;;; arglist and that only keywords present in the list KEYS are
1814 (declaim (ftype (function (list list) boolean) check-transform-keys))
1815 (defun check-transform-keys (args keys)
1816 (and (check-key-args-constant args)
1817 (do ((arg args (cddr arg)))
1819 (unless (member (continuation-value (first arg)) keys)
1824 ;;; Called by the expansion of the EVENT macro.
1825 (declaim (ftype (function (event-info (or node null)) *) %event))
1826 (defun %event (info node)
1827 (incf (event-info-count info))
1828 (when (and (>= (event-info-level info) *event-note-threshold*)
1829 (policy (or node *lexenv*)
1830 (= inhibit-warnings 0)))
1831 (let ((*compiler-error-context* node))
1832 (compiler-note (event-info-description info))))
1834 (let ((action (event-info-action info)))
1835 (when action (funcall action node))))