X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fdfo.lisp;h=291a1cbd88734843caa43453d9eb703d826484ff;hb=2d3cb6dba6461e98744eca2a1df4f770cea468ca;hp=41075214a5418f0c34d33e063beffa33f3c00746;hpb=0cfad881b88e03971a2b3ef0c0c0fc2e5f4f1bc8;p=sbcl.git diff --git a/src/compiler/dfo.lisp b/src/compiler/dfo.lisp index 4107521..291a1cb 100644 --- a/src/compiler/dfo.lisp +++ b/src/compiler/dfo.lisp @@ -25,7 +25,6 @@ (unless (block-flag ep) (find-dfo-aux ep head component) (return nil)))))) - (let ((num 0)) (declare (fixnum num)) (do-blocks-backwards (block component :both) @@ -60,7 +59,7 @@ (unless (eq old-next old-tail) (setf (block-next head) old-next) (setf (block-prev old-next) head) - + (setf (block-prev next) old-last) (setf (block-next old-last) next)) @@ -70,9 +69,10 @@ (setf (component-lambdas new) (nconc (component-lambdas old) (component-lambdas new))) (setf (component-lambdas old) nil) - (setf (component-new-funs new) (nconc (component-new-funs old) - (component-new-funs new)) - (component-new-funs old) nil) + (setf (component-new-functionals new) + (nconc (component-new-functionals old) + (component-new-functionals new))) + (setf (component-new-functionals old) nil) (dolist (xp (block-pred old-tail)) (unlink-blocks xp old-tail) @@ -89,22 +89,19 @@ (defun find-dfo-aux (block head component) (unless (eq (block-component block) component) (join-components component (block-component block))) - (unless (block-flag block) (setf (block-flag block) t) (dolist (succ (block-succ block)) (find-dfo-aux succ head component)) - (remove-from-dfo block) (add-to-dfo block head)) (values)) ;;; This function is called on each block by FIND-INITIAL-DFO-AUX -;;; before it walks the successors. It looks at the home lambda's bind -;;; block to see whether that block is in some other component: - +;;; before it walks the successors. It looks at the home CLAMBDA's +;;; BIND block to see whether that block is in some other component: ;;; -- If the block is in the initial component, then do -;;; DFO-WALK-CALL-GRAPH on the home function to move it +;;; DFO-SCAVENGE-DEPENDENCY-GRAPH on the home function to move it ;;; into COMPONENT. ;;; -- If the block is in some other component, join COMPONENT into ;;; it and return that component. @@ -117,15 +114,14 @@ ;;; the same component, even when they might not seem reachable from ;;; the environment entry. Consider the case of code that is only ;;; reachable from a non-local exit. -(defun walk-home-call-graph (block component) +(defun scavenge-home-dependency-graph (block component) (declare (type cblock block) (type component component)) - (let ((home (block-home-lambda block))) - (if (eq (functional-kind home) :deleted) + (let ((home-lambda (block-home-lambda block))) + (if (eq (functional-kind home-lambda) :deleted) component - (let* ((bind-block (node-block (lambda-bind home))) - (home-component (block-component bind-block))) + (let ((home-component (lambda-component home-lambda))) (cond ((eq (component-kind home-component) :initial) - (dfo-scavenge-call-graph home component)) + (dfo-scavenge-dependency-graph home-lambda component)) ((eq home-component component) component) (t @@ -156,10 +152,9 @@ ((block-flag block) component) (t (setf (block-flag block) t) - (let ((current (walk-home-call-graph block component))) + (let ((current (scavenge-home-dependency-graph block component))) (dolist (succ (block-succ block)) (setq current (find-initial-dfo-aux succ current))) - (remove-from-dfo block) (add-to-dfo block (component-head current)) current))))) @@ -192,9 +187,17 @@ (res home)))) (res))) -;;; Move the code for FUN and all functions called by it into -;;; COMPONENT. If FUN is already in COMPONENT, then we just return -;;; that component. +;;; If CLAMBDA is already in COMPONENT, just return that +;;; component. Otherwise, move the code for CLAMBDA and all lambdas it +;;; physically depends on (either because of calls or because of +;;; closure relationships) into COMPONENT, or possibly into another +;;; COMPONENT that we find to be related. Return whatever COMPONENT we +;;; actually merged into. +;;; +;;; (Note: The analogous CMU CL code only scavenged call-based +;;; dependencies, not closure dependencies. That seems to've been by +;;; oversight, not by design, as per the bug reported by WHN on +;;; cmucl-imp ca. 2001-11-29 and explained by DTC shortly after.) ;;; ;;; If the function is in an initial component, then we move its head ;;; and tail to COMPONENT and add it to COMPONENT's lambdas. It is @@ -202,16 +205,16 @@ ;;; unreachable) because if the return is unreachable it (and its ;;; successor link) will be deleted in the post-deletion pass. ;;; -;;; We then do a FIND-DFO-AUX starting at the head of FUN. If this +;;; We then do a FIND-DFO-AUX starting at the head of CLAMBDA. If this ;;; flow-graph walk encounters another component (which can only ;;; happen due to a non-local exit), then we move code into that ;;; component instead. We then recurse on all functions called from -;;; FUN, moving code into whichever component the preceding call +;;; CLAMBDA, moving code into whichever component the preceding call ;;; returned. ;;; -;;; If FUN is in the initial component, but the BLOCK-FLAG is set in -;;; the bind block, then we just return COMPONENT, since we must have -;;; already reached this function in the current walk (or the +;;; If CLAMBDA is in the initial component, but the BLOCK-FLAG is set +;;; in the bind block, then we just return COMPONENT, since we must +;;; have already reached this function in the current walk (or the ;;; component would have been changed). ;;; ;;; If the function is an XEP, then we also walk all functions that @@ -220,56 +223,79 @@ ;;; ensures that conversion of a full call to a local call won't ;;; result in a need to join components, since the components will ;;; already be one. -(defun dfo-scavenge-call-graph (fun component) - (declare (type clambda fun) (type component component)) - (/show "entering DFO-SCAVENGE-CALL-GRAPH" fun component) - (let* ((bind-block (node-block (lambda-bind fun))) +(defun dfo-scavenge-dependency-graph (clambda component) + (declare (type clambda clambda) (type component component)) + (assert (not (eql (lambda-kind clambda) :deleted))) + (let* ((bind-block (node-block (lambda-bind clambda))) (old-lambda-component (block-component bind-block)) - (return (lambda-return fun))) + (return (lambda-return clambda))) (cond ((eq old-lambda-component component) - (/show "LAMBDA is already in COMPONENT") component) ((not (eq (component-kind old-lambda-component) :initial)) - (/show "joining COMPONENTs") (join-components old-lambda-component component) old-lambda-component) ((block-flag bind-block) - (/show "do-nothing (BLOCK-FLAG BIND-BLOCK) case") component) (t - (/show "full scavenge case") - (push fun (component-lambdas component)) + (push clambda (component-lambdas component)) (setf (component-lambdas old-lambda-component) - (delete fun (component-lambdas old-lambda-component))) + (delete clambda (component-lambdas old-lambda-component))) (link-blocks (component-head component) bind-block) (unlink-blocks (component-head old-lambda-component) bind-block) (when return (let ((return-block (node-block return))) (link-blocks return-block (component-tail component)) (unlink-blocks return-block (component-tail old-lambda-component)))) - - (/show (functional-kind fun)) - (/show (lambda-calls fun)) - (when (eq (functional-kind fun) :external) - (/show (find-reference-funs fun))) - - (let ((calls (if (eq (functional-kind fun) :external) - (append (find-reference-funs fun) - (lambda-calls fun)) - (lambda-calls fun)))) - (do ((res (find-initial-dfo-aux bind-block component) - (dfo-scavenge-call-graph (first funs) res)) - (funs calls (rest funs))) - ((null funs) res) - (declare (type component res)))))))) - -;;; Return true if FUN is either an XEP or has EXITS to some of its -;;; ENTRIES. -(defun has-xep-or-nlx (fun) - (declare (type clambda fun)) - (or (eq (functional-kind fun) :external) - (let ((entries (lambda-entries fun))) + (let ((res (find-initial-dfo-aux bind-block component))) + (declare (type component res)) + ;; Scavenge related lambdas. + (labels ((scavenge-lambda (clambda) + (setf res + (dfo-scavenge-dependency-graph (lambda-home clambda) + res))) + (scavenge-possibly-deleted-lambda (clambda) + (unless (eql (lambda-kind clambda) :deleted) + (scavenge-lambda clambda))) + ;; Scavenge call relationship. + (scavenge-call (called-lambda) + (scavenge-lambda called-lambda)) + ;; Scavenge closure over a variable: if CLAMBDA + ;; refers to a variable whose home lambda is not + ;; CLAMBDA, then the home lambda should be in the + ;; same component as CLAMBDA. (sbcl-0.6.13, and CMU + ;; CL, didn't do this, leading to the occasional + ;; failure when physenv analysis, which is local to + ;; each component, would bogusly conclude that a + ;; closed-over variable was unused and thus delete + ;; it. See e.g. cmucl-imp 2001-11-29.) + (scavenge-closure-var (var) + (unless (null (lambda-var-refs var)) ; unless var deleted + (let ((var-home-home (lambda-home (lambda-var-home var)))) + (scavenge-possibly-deleted-lambda var-home-home)))) + ;; Scavenge closure over an entry for nonlocal exit. + ;; This is basically parallel to closure over a + ;; variable above. + (scavenge-entry (entry) + (declare (type entry entry)) + (let ((entry-home (node-home-lambda entry))) + (scavenge-possibly-deleted-lambda entry-home)))) + (dolist (cc (lambda-calls-or-closes clambda)) + (etypecase cc + (clambda (scavenge-call cc)) + (lambda-var (scavenge-closure-var cc)) + (entry (scavenge-entry cc)))) + (when (eq (lambda-kind clambda) :external) + (mapc #'scavenge-call (find-reference-funs clambda)))) + ;; Voila. + res))))) + +;;; Return true if CLAMBDA either is an XEP or has EXITS to some of +;;; its ENTRIES. +(defun has-xep-or-nlx (clambda) + (declare (type clambda clambda)) + (or (eq (functional-kind clambda) :external) + (let ((entries (lambda-entries clambda))) (and entries (find-if #'entry-exits entries))))) @@ -321,8 +347,8 @@ (values (real) (top) (real-top)))) -;; COMPONENTs want strings for names, LEAF-DEBUG-NAMEs mightn't be -;; strings.. +;;; COMPONENTs want strings for names, LEAF-DEBUG-NAMEs mightn't be +;;; strings... (defun component-name-from-functional-debug-name (functional) (declare (type functional functional)) (let ((leaf-debug-name (leaf-debug-name functional))) @@ -343,25 +369,20 @@ ;;; blocks. We assume that the FLAGS have already been cleared. (defun find-initial-dfo (toplevel-lambdas) (declare (list toplevel-lambdas)) - (/show "entering FIND-INITIAL-DFO" toplevel-lambdas) (collect ((components)) ;; We iterate over the lambdas in each initial component, trying ;; to put each function in its own component, but joining it to ;; an existing component if we find that there are references ;; between them. Any code that is left in an initial component ;; must be unreachable, so we can delete it. Stray links to the - ;; initial component tail (due NIL function terminated blocks) - ;; are moved to the appropriate newc component tail. + ;; initial component tail (due to NIL function terminated blocks) + ;; are moved to the appropriate new component tail. (dolist (toplevel-lambda toplevel-lambdas) - (/show toplevel-lambda) - (let* ((block (node-block (lambda-bind toplevel-lambda))) - (old-component (block-component block)) + (let* ((old-component (lambda-component toplevel-lambda)) (old-component-lambdas (component-lambdas old-component)) (new-component nil)) - (/show old-component old-component-lambdas) (aver (member toplevel-lambda old-component-lambdas)) (dolist (component-lambda old-component-lambdas) - (/show component-lambda) (aver (member (functional-kind component-lambda) '(:optional :external :toplevel nil :escape :cleanup))) @@ -374,15 +395,14 @@ ;; seem a better name than just "". (component-name-from-functional-debug-name component-lambda))) - (let ((res (dfo-scavenge-call-graph component-lambda new-component))) + (let ((res (dfo-scavenge-dependency-graph component-lambda + new-component))) (when (eq res new-component) - (/show "saving" new-component (component-lambdas new-component)) (aver (not (position new-component (components)))) (components new-component) (setq new-component nil)))) (when (eq (component-kind old-component) :initial) (aver (null (component-lambdas old-component))) - (/show "clearing/deleting OLD-COMPONENT because KIND=:INITIAL") (let ((tail (component-tail old-component))) (dolist (pred (block-pred tail)) (let ((pred-component (block-component pred))) @@ -402,7 +422,7 @@ (separate-toplevelish-components (components)))) ;;; Insert the code in LAMBDA at the end of RESULT-LAMBDA. -(defun merge-1-tl-lambda (result-lambda lambda) +(defun merge-1-toplevel-lambda (result-lambda lambda) (declare (type clambda result-lambda lambda)) ;; Delete the lambda, and combine the LETs and entries. @@ -418,8 +438,7 @@ (let* ((bind (lambda-bind lambda)) (bind-block (node-block bind)) (component (block-component bind-block)) - (result-component - (block-component (node-block (lambda-bind result-lambda)))) + (result-component (lambda-component result-lambda)) (result-return-block (node-block (lambda-return result-lambda)))) ;; Move blocks into the new COMPONENT, and move any nodes directly @@ -500,13 +519,10 @@ (add-continuation-use use new)))) (dolist (lambda (rest lambdas)) - (merge-1-tl-lambda result-lambda lambda))) + (merge-1-toplevel-lambda result-lambda lambda))) (t (dolist (lambda (rest lambdas)) - (setf (functional-entry-function lambda) nil) - (delete-component - (block-component - (node-block (lambda-bind lambda))))))) + (setf (functional-entry-fun lambda) nil) + (delete-component (lambda-component lambda))))) - (values (block-component (node-block (lambda-bind result-lambda))) - result-lambda))) + (values (lambda-component result-lambda) result-lambda)))