X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fdfo.lisp;h=ca91eab36dcd08d462e3948ff815b0a34036b24c;hb=09957fcf57b49ed5ae5f05d62ad12d7ddbfd8e1d;hp=f50948090284cbe64dfd83b8b6b0aff6c757df78;hpb=419ce099442b9bffe41eff8516c6a2be085259de;p=sbcl.git diff --git a/src/compiler/dfo.lisp b/src/compiler/dfo.lisp index f509480..ca91eab 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) @@ -89,12 +88,10 @@ (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)) @@ -103,7 +100,7 @@ ;;; 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. @@ -116,14 +113,14 @@ ;;; 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-lambda (block-home-lambda block))) (if (eq (functional-kind home-lambda) :deleted) component (let ((home-component (lambda-component home-lambda))) (cond ((eq (component-kind home-component) :initial) - (dfo-scavenge-call-graph home-lambda component)) + (dfo-scavenge-dependency-graph home-lambda component)) ((eq home-component component) component) (t @@ -154,10 +151,9 @@ ((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))))) @@ -190,9 +186,17 @@ (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 not 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 @@ -200,16 +204,16 @@ ;;; 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 @@ -218,11 +222,12 @@ ;;; 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)) - (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) component) @@ -232,33 +237,64 @@ ((block-flag bind-block) component) (t - (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)))) - - (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 remaining-calls) res)) - (remaining-calls calls (rest remaining-calls))) - ((null remaining-calls) - 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))))) @@ -341,8 +377,7 @@ ;; initial component tail (due NIL function terminated blocks) ;; are moved to the appropriate new component tail. (dolist (toplevel-lambda toplevel-lambdas) - (let* ((block (lambda-block toplevel-lambda)) - (old-component (block-component block)) + (let* ((old-component (lambda-component toplevel-lambda)) (old-component-lambdas (component-lambdas old-component)) (new-component nil)) (aver (member toplevel-lambda old-component-lambdas)) @@ -359,7 +394,8 @@ ;; 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) (aver (not (position new-component (components)))) (components new-component)