X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fir1opt.lisp;h=328792933834fde470cf84442240f1fbbaea4f9f;hb=8a55e8e2feb7fd0faaaed6d420beec97dade94e4;hp=259bc7738b853f1182a9022ff6eb47f19d7d917e;hpb=6e7e59adb6f6c30f84b31695b48cb51e2c519d75;p=sbcl.git diff --git a/src/compiler/ir1opt.lisp b/src/compiler/ir1opt.lisp index 259bc77..3287929 100644 --- a/src/compiler/ir1opt.lisp +++ b/src/compiler/ir1opt.lisp @@ -118,6 +118,41 @@ (declaim (ftype (function (continuation) ctype) continuation-type)) (defun continuation-type (cont) (single-value-type (continuation-derived-type cont))) + +;;; If CONT is an argument of a function, return a type which the +;;; function checks CONT for. +#!-sb-fluid (declaim (inline continuation-externally-checkable-type)) +(defun continuation-externally-checkable-type (cont) + (or (continuation-%externally-checkable-type cont) + (%continuation-%externally-checkable-type cont))) +(defun %continuation-%externally-checkable-type (cont) + (declare (type continuation cont)) + (let ((dest (continuation-dest cont))) + (if (not (and dest (combination-p dest))) + ;; TODO: MV-COMBINATION + (setf (continuation-%externally-checkable-type cont) *wild-type*) + (let* ((fun (combination-fun dest)) + (args (combination-args dest)) + (fun-type (continuation-type fun))) + (if (or (not (fun-type-p fun-type)) + ;; FUN-TYPE might be (AND FUNCTION (SATISFIES ...)). + (fun-type-wild-args fun-type)) + (progn (dolist (arg args) + (setf (continuation-%externally-checkable-type arg) + *wild-type*)) + *wild-type*) + (let* ((arg-types (append (fun-type-required fun-type) + (fun-type-optional fun-type) + (let ((rest (list (or (fun-type-rest fun-type) + *wild-type*)))) + (setf (cdr rest) rest))))) + ;; TODO: &KEY + (loop + for arg of-type continuation in args + and type of-type ctype in arg-types + do (setf (continuation-%externally-checkable-type arg) + type)) + (continuation-%externally-checkable-type cont))))))) ;;;; interface routines used by optimizers @@ -233,26 +268,33 @@ ;;; and doing IR1 optimizations. We can ignore all blocks that don't ;;; have the REOPTIMIZE flag set. If COMPONENT-REOPTIMIZE is true when ;;; we are done, then another iteration would be beneficial. -;;; -;;; We delete blocks when there is either no predecessor or the block -;;; is in a lambda that has been deleted. These blocks would -;;; eventually be deleted by DFO recomputation, but doing it here -;;; immediately makes the effect available to IR1 optimization. (defun ir1-optimize (component) (declare (type component component)) (setf (component-reoptimize component) nil) (do-blocks (block component) (cond ((or (block-delete-p block) - (null (block-pred block)) - (eq (functional-kind (block-home-lambda block)) :deleted)) + (null (block-pred block))) (delete-block block)) + ((eq (functional-kind (block-home-lambda block)) :deleted) + ;; Preserve the BLOCK-SUCC invariant that almost every block has + ;; one successor (and a block with DELETE-P set is an acceptable + ;; exception). + (labels ((mark-blocks (block) + (dolist (pred (block-pred block)) + (when (and (not (block-delete-p pred)) + (eq (functional-kind (block-home-lambda pred)) + :deleted)) + (setf (block-delete-p pred) t) + (mark-blocks pred))))) + (mark-blocks block) + (delete-block block))) (t (loop (let ((succ (block-succ block))) (unless (and succ (null (rest succ))) (return))) - + (let ((last (block-last block))) (typecase last (cif @@ -262,56 +304,66 @@ (exit (when (maybe-delete-exit last) (return))))) - - (unless (join-successor-if-possible block) + + (unless (join-successor-if-possible block) (return))) (when (and (block-reoptimize block) (block-component block)) (aver (not (block-delete-p block))) (ir1-optimize-block block)) + ;; We delete blocks when there is either no predecessor or the + ;; block is in a lambda that has been deleted. These blocks + ;; would eventually be deleted by DFO recomputation, but doing + ;; it here immediately makes the effect available to IR1 + ;; optimization. (when (and (block-flush-p block) (block-component block)) (aver (not (block-delete-p block))) (flush-dead-code block))))) (values)) -;;; Loop over the nodes in BLOCK, looking for stuff that needs to be -;;; optimized. We dispatch off of the type of each node with its -;;; reoptimize flag set: - -;;; -- With a COMBINATION, we call PROPAGATE-FUN-CHANGE whenever -;;; the function changes, and call IR1-OPTIMIZE-COMBINATION if any -;;; argument changes. -;;; -- With an EXIT, we derive the node's type from the VALUE's type. -;;; We don't propagate CONT's assertion to the VALUE, since if we -;;; did, this would move the checking of CONT's assertion to the -;;; exit. This wouldn't work with CATCH and UWP, where the EXIT -;;; node is just a placeholder for the actual unknown exit. +;;; Loop over the nodes in BLOCK, acting on (and clearing) REOPTIMIZE +;;; flags. ;;; -;;; Note that we clear the node & block reoptimize flags *before* -;;; doing the optimization. This ensures that the node or block will -;;; be reoptimized if necessary. We leave the NODE-OPTIMIZE flag set -;;; going into IR1-OPTIMIZE-RETURN, since IR1-OPTIMIZE-RETURN wants to -;;; clear the flag itself. +;;; Note that although they are cleared here, REOPTIMIZE flags might +;;; still be set upon return from this function, meaning that further +;;; optimization is wanted (as a consequence of optimizations we did). (defun ir1-optimize-block (block) (declare (type cblock block)) + ;; We clear the node and block REOPTIMIZE flags before doing the + ;; optimization, not after. This ensures that the node or block will + ;; be reoptimized if necessary. (setf (block-reoptimize block) nil) (do-nodes (node cont block :restart-p t) (when (node-reoptimize node) + ;; As above, we clear the node REOPTIMIZE flag before optimizing. (setf (node-reoptimize node) nil) (typecase node (ref) (combination + ;; With a COMBINATION, we call PROPAGATE-FUN-CHANGE whenever + ;; the function changes, and call IR1-OPTIMIZE-COMBINATION if + ;; any argument changes. (ir1-optimize-combination node)) (cif (ir1-optimize-if node)) (creturn + ;; KLUDGE: We leave the NODE-OPTIMIZE flag set going into + ;; IR1-OPTIMIZE-RETURN, since IR1-OPTIMIZE-RETURN wants to + ;; clear the flag itself. -- WHN 2002-02-02, quoting original + ;; CMU CL comments (setf (node-reoptimize node) t) (ir1-optimize-return node)) (mv-combination (ir1-optimize-mv-combination node)) (exit + ;; With an EXIT, we derive the node's type from the VALUE's + ;; type. We don't propagate CONT's assertion to the VALUE, + ;; since if we did, this would move the checking of CONT's + ;; assertion to the exit. This wouldn't work with CATCH and + ;; UWP, where the EXIT node is just a placeholder for the + ;; actual unknown exit. (let ((value (exit-value node))) (when value (derive-node-type node (continuation-derived-type value))))) @@ -321,21 +373,6 @@ ;;; Try to join with a successor block. If we succeed, we return true, ;;; otherwise false. -;;; -;;; We cannot combine with a successor block if: -;;; 1. The successor has more than one predecessor. -;;; 2. The last node's CONT is also used somewhere else. -;;; 3. The successor is the current block (infinite loop). -;;; 4. The next block has a different cleanup, and thus we may want -;;; to insert cleanup code between the two blocks at some point. -;;; 5. The next block has a different home lambda, and thus the -;;; control transfer is a non-local exit. -;;; -;;; Joining is easy when the successor's START continuation is the -;;; same from our LAST's CONT. If they differ, then we can still join -;;; when the last continuation has no next and the next continuation -;;; has no uses. In this case, we replace the next continuation with -;;; the last before joining the blocks. (defun join-successor-if-possible (block) (declare (type cblock block)) (let ((next (first (block-succ block)))) @@ -343,22 +380,39 @@ (let* ((last (block-last block)) (last-cont (node-cont last)) (next-cont (block-start next))) - (cond ((or (rest (block-pred next)) - (not (eq (continuation-use last-cont) last)) - (eq next block) - (not (eq (block-end-cleanup block) - (block-start-cleanup next))) - (not (eq (block-home-lambda block) - (block-home-lambda next)))) + (cond (;; We cannot combine with a successor block if: + (or + ;; The successor has more than one predecessor. + (rest (block-pred next)) + ;; The last node's CONT is also used somewhere else. + (not (eq (continuation-use last-cont) last)) + ;; The successor is the current block (infinite loop). + (eq next block) + ;; The next block has a different cleanup, and thus + ;; we may want to insert cleanup code between the + ;; two blocks at some point. + (not (eq (block-end-cleanup block) + (block-start-cleanup next))) + ;; The next block has a different home lambda, and + ;; thus the control transfer is a non-local exit. + (not (eq (block-home-lambda block) + (block-home-lambda next)))) nil) + ;; Joining is easy when the successor's START + ;; continuation is the same from our LAST's CONT. ((eq last-cont next-cont) (join-blocks block next) t) + ;; If they differ, then we can still join when the last + ;; continuation has no next and the next continuation + ;; has no uses. ((and (null (block-start-uses next)) (eq (continuation-kind last-cont) :inside-block)) + ;; In this case, we replace the next + ;; continuation with the last before joining the blocks. (let ((next-node (continuation-next next-cont))) ;; If NEXT-CONT does have a dest, it must be - ;; unreachable, since there are no uses. + ;; unreachable, since there are no USES. ;; DELETE-CONTINUATION will mark the dest block as ;; DELETE-P [and also this block, unless it is no ;; longer backward reachable from the dest block.] @@ -407,13 +461,9 @@ (values)) -;;; Delete any nodes in BLOCK whose value is unused and have no -;;; side-effects. We can delete sets of lexical variables when the set +;;; Delete any nodes in BLOCK whose value is unused and which have no +;;; side effects. We can delete sets of lexical variables when the set ;;; variable has no references. -;;; -;;; [### For now, don't delete potentially flushable calls when they -;;; have the CALL attribute. Someday we should look at the functional -;;; args to determine if they have any side-effects.] (defun flush-dead-code (block) (declare (type cblock block)) (do-nodes-backwards (node cont block) @@ -426,8 +476,25 @@ (let ((info (combination-kind node))) (when (fun-info-p info) (let ((attr (fun-info-attributes info))) - (when (and (ir1-attributep attr flushable) - (not (ir1-attributep attr call))) + (when (and (not (ir1-attributep attr call)) + ;; ### For now, don't delete potentially + ;; flushable calls when they have the CALL + ;; attribute. Someday we should look at the + ;; functional args to determine if they have + ;; any side effects. + (if (policy node (= safety 3)) + (and (ir1-attributep attr flushable) + (every (lambda (arg) + (member (continuation-type-check arg) + '(nil :deleted))) + (basic-combination-args node)) + (valid-fun-use node + (info :function :type + (leaf-source-name (ref-leaf (continuation-use (basic-combination-fun node))))) + :result-test #'always-subtypep + :lossage-fun nil + :unwinnage-fun nil)) + (ir1-attributep attr unsafely-flushable))) (flush-dest (combination-fun node)) (dolist (arg (combination-args node)) (flush-dest arg)) @@ -595,6 +662,7 @@ (new-block (continuation-starts-block new-cont))) (link-node-to-previous-continuation new-node new-cont) (setf (continuation-dest new-cont) new-node) + (setf (continuation-%externally-checkable-type new-cont) nil) (add-continuation-use new-node dummy-cont) (setf (block-last new-block) new-node) @@ -618,9 +686,9 @@ ;;; This function attempts to delete an exit node, returning true if ;;; it deletes the block as a consequence: -;;; -- If the exit is degenerate (has no Entry), then we don't do +;;; -- If the exit is degenerate (has no ENTRY), then we don't do ;;; anything, since there is nothing to be done. -;;; -- If the exit node and its Entry have the same home lambda then +;;; -- If the exit node and its ENTRY have the same home lambda then ;;; we know the exit is local, and can delete the exit. We change ;;; uses of the Exit-Value to be uses of the original continuation, ;;; then unlink the node. If the exit is to a TR context, then we @@ -699,9 +767,7 @@ ;; cross-compiler can't fold it because the ;; cross-compiler doesn't know how to evaluate it. #+sb-xc-host - (let* ((ref (continuation-use (combination-fun node))) - (fun-name (leaf-source-name (ref-leaf ref)))) - (fboundp fun-name))) + (fboundp (combination-fun-source-name node))) (constant-fold-call node) (return-from ir1-optimize-combination))) @@ -917,30 +983,31 @@ (continuation-use (basic-combination-fun call)) call)) ((not leaf)) - ((or (info :function :source-transform (leaf-source-name leaf)) - (and info - (ir1-attributep (fun-info-attributes info) - predicate) - (let ((dest (continuation-dest (node-cont call)))) - (and dest (not (if-p dest)))))) - (when (and (leaf-has-source-name-p leaf) - ;; FIXME: This SYMBOLP is part of a literal - ;; translation of a test in the old CMU CL - ;; source, and it's not quite clear what - ;; the old source meant. Did it mean "has a - ;; valid name"? Or did it mean "is an - ;; ordinary function name, not a SETF - ;; function"? Either way, the old CMU CL - ;; code probably didn't deal with SETF - ;; functions correctly, and neither does - ;; this new SBCL code, and that should be fixed. - (symbolp (leaf-source-name leaf))) - (let ((dummies (make-gensym-list (length - (combination-args call))))) - (transform-call call - `(lambda ,dummies - (,(leaf-source-name leaf) - ,@dummies))))))))))) + ((and (leaf-has-source-name-p leaf) + (or (info :function :source-transform (leaf-source-name leaf)) + (and info + (ir1-attributep (fun-info-attributes info) + predicate) + (let ((dest (continuation-dest (node-cont call)))) + (and dest (not (if-p dest))))))) + ;; FIXME: This SYMBOLP is part of a literal + ;; translation of a test in the old CMU CL + ;; source, and it's not quite clear what + ;; the old source meant. Did it mean "has a + ;; valid name"? Or did it mean "is an + ;; ordinary function name, not a SETF + ;; function"? Either way, the old CMU CL + ;; code probably didn't deal with SETF + ;; functions correctly, and neither does + ;; this new SBCL code, and that should be fixed. + (when (symbolp (leaf-source-name leaf)) + (let ((dummies (make-gensym-list + (length (combination-args call))))) + (transform-call call + `(lambda ,dummies + (,(leaf-source-name leaf) + ,@dummies)) + (leaf-source-name leaf)))))))))) (values)) ;;;; known function optimization @@ -975,24 +1042,13 @@ (policy node (>= speed inhibit-warnings)) (policy node (> speed inhibit-warnings)))) (*compiler-error-context* node)) - (cond ((not (member (transform-when transform) - '(:native :both))) - ;; FIXME: Make sure that there's a transform for - ;; (MEMBER SYMBOL ..) into MEMQ. - ;; FIXME: Note that when/if I make SHARE operation to shared - ;; constant data between objects in the system, remember that a - ;; SHAREd list, or other SHAREd compound object, can be processed - ;; recursively, so that e.g. the two lists above can share their - ;; '(:BOTH) tail sublists. - (let ((when (transform-when transform))) - (not (or (eq when :both) - (eq when :native)))) - t) - ((or (not constrained) + (cond ((or (not constrained) (valid-fun-use node type :strict-result t)) (multiple-value-bind (severity args) (catch 'give-up-ir1-transform - (transform-call node (funcall fun node)) + (transform-call node + (funcall fun node) + (combination-fun-source-name node)) (values :none nil)) (ecase severity (:none @@ -1088,21 +1144,31 @@ (setf (component-reoptimize (block-component block)) t))))))) reoptimize)) - ;;; Take the lambda-expression RES, IR1 convert it in the proper ;;; environment, and then install it as the function for the call ;;; NODE. We do local call analysis so that the new function is ;;; integrated into the control flow. -(defun transform-call (node res) +;;; +;;; We require the original function source name in order to generate +;;; a meaningful debug name for the lambda we set up. (It'd be +;;; possible to do this starting from debug names as well as source +;;; names, but as of sbcl-0.7.1.5, there was no need for this +;;; generality, since source names are always known to our callers.) +(defun transform-call (node res source-name) (declare (type combination node) (list res)) + (aver (and (legal-fun-name-p source-name) + (not (eql source-name '.anonymous.)))) (with-ir1-environment-from-node node (let ((new-fun (ir1-convert-inline-lambda res - :debug-name "something inlined in TRANSFORM-CALL")) - (ref (continuation-use (combination-fun node)))) - (change-ref-leaf ref new-fun) - (setf (combination-kind node) :full) - (locall-analyze-component *current-component*))) + :debug-name (debug-namify "LAMBDA-inlined ~A" + (as-debug-name + source-name + "")))) + (ref (continuation-use (combination-fun node)))) + (change-ref-leaf ref new-fun) + (setf (combination-kind node) :full) + (locall-analyze-component *current-component*))) (values)) ;;; Replace a call to a foldable function of constant arguments with @@ -1114,24 +1180,56 @@ ;;; call a :ERROR call. ;;; ;;; If there is more than one value, then we transform the call into a -;;; values form. +;;; VALUES form. (defun constant-fold-call (call) - (declare (type combination call)) - (let* ((args (mapcar #'continuation-value (combination-args call))) - (ref (continuation-use (combination-fun call))) - (fun-name (leaf-source-name (ref-leaf ref)))) - + (let ((args (mapcar #'continuation-value (combination-args call))) + (fun-name (combination-fun-source-name call))) (multiple-value-bind (values win) - (careful-call fun-name args call "constant folding") + (careful-call fun-name + args + call + ;; Note: CMU CL had COMPILER-WARN here, and that + ;; seems more natural, but it's probably not. + ;; + ;; It's especially not while bug 173 exists: + ;; Expressions like + ;; (COND (END + ;; (UNLESS (OR UNSAFE? (<= END SIZE))) + ;; ...)) + ;; can cause constant-folding TYPE-ERRORs (in + ;; #'<=) when END can be proved to be NIL, even + ;; though the code is perfectly legal and safe + ;; because a NIL value of END means that the + ;; #'<= will never be executed. + ;; + ;; Moreover, even without bug 173, + ;; quite-possibly-valid code like + ;; (COND ((NONINLINED-PREDICATE END) + ;; (UNLESS (<= END SIZE)) + ;; ...)) + ;; (where NONINLINED-PREDICATE is something the + ;; compiler can't do at compile time, but which + ;; turns out to make the #'<= expression + ;; unreachable when END=NIL) could cause errors + ;; when the compiler tries to constant-fold (<= + ;; END SIZE). + ;; + ;; So, with or without bug 173, it'd be + ;; unnecessarily evil to do a full + ;; COMPILER-WARNING (and thus return FAILURE-P=T + ;; from COMPILE-FILE) for legal code, so we we + ;; use a wimpier COMPILE-STYLE-WARNING instead. + #'compiler-style-warn + "constant folding") (if (not win) - (setf (combination-kind call) :error) - (let ((dummies (make-gensym-list (length args)))) - (transform-call - call - `(lambda ,dummies - (declare (ignore ,@dummies)) - (values ,@(mapcar (lambda (x) `',x) values)))))))) - + (setf (combination-kind call) :error) + (let ((dummies (make-gensym-list (length args)))) + (transform-call + call + `(lambda ,dummies + (declare (ignore ,@dummies)) + (values ,@(mapcar (lambda (x) `',x) values))) + fun-name))))) (values)) ;;;; local call optimization @@ -1178,7 +1276,7 @@ (derive-node-type node (continuation-type (set-value node))) (values)) -;;; Return true if the value of Ref will always be the same (and is +;;; Return true if the value of REF will always be the same (and is ;;; thus legal to substitute.) (defun constant-reference-p (ref) (declare (type ref ref)) @@ -1205,7 +1303,7 @@ ;;; -- the var's DEST has a different policy than the ARG's (think safety). ;;; ;;; We change the REF to be a reference to NIL with unused value, and -;;; let it be flushed as dead code. A side-effect of this substitution +;;; let it be flushed as dead code. A side effect of this substitution ;;; is to delete the variable. (defun substitute-single-use-continuation (arg var) (declare (type continuation arg) (type lambda-var var)) @@ -1239,15 +1337,15 @@ ;;; any unreferenced variables. Note that FLUSH-DEAD-CODE will come ;;; along right away and delete the REF and then the lambda, since we ;;; flush the FUN continuation. -(defun delete-let (fun) - (declare (type clambda fun)) - (aver (member (functional-kind fun) '(:let :mv-let))) - (note-unreferenced-vars fun) - (let ((call (let-combination fun))) +(defun delete-let (clambda) + (declare (type clambda clambda)) + (aver (functional-letlike-p clambda)) + (note-unreferenced-vars clambda) + (let ((call (let-combination clambda))) (flush-dest (basic-combination-fun call)) (unlink-node call) - (unlink-node (lambda-bind fun)) - (setf (lambda-bind fun) nil)) + (unlink-node (lambda-bind clambda)) + (setf (lambda-bind clambda) nil)) (values)) ;;; This function is called when one of the arguments to a LET @@ -1553,7 +1651,8 @@ (flush-dest (combination-fun use)) (let ((fun-cont (basic-combination-fun call))) (setf (continuation-dest fun-cont) use) - (setf (combination-fun use) fun-cont)) + (setf (combination-fun use) fun-cont) + (setf (continuation-%externally-checkable-type fun-cont) nil)) (setf (combination-kind use) :local) (setf (functional-kind fun) :let) (flush-dest (first (basic-combination-args call))) @@ -1583,7 +1682,8 @@ (setf (combination-kind node) :full) (let ((args (combination-args use))) (dolist (arg args) - (setf (continuation-dest arg) node)) + (setf (continuation-dest arg) node) + (setf (continuation-%externally-checkable-type arg) nil)) (setf (combination-args use) nil) (flush-dest list) (setf (combination-args node) args))