X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Flocall.lisp;h=716afa1d8127597e52bfa56e8baad433b2c7f763;hb=5ec8d0c1c8b7939818b75118b472fac1af554f9a;hp=8c1843263048c39008176a91601c3e906d0d8386;hpb=6c765578c8dc4bcc7798e37c9918715f198b30da;p=sbcl.git diff --git a/src/compiler/locall.lisp b/src/compiler/locall.lisp index 8c18432..716afa1 100644 --- a/src/compiler/locall.lisp +++ b/src/compiler/locall.lisp @@ -21,13 +21,14 @@ (in-package "SB!C") -;;; This function propagates information from the variables in the function -;;; Fun to the actual arguments in Call. This is also called by the VALUES IR1 -;;; optimizer when it sleazily converts MV-BINDs to LETs. +;;; This function propagates information from the variables in the +;;; function FUN to the actual arguments in CALL. This is also called +;;; by the VALUES IR1 optimizer when it sleazily converts MV-BINDs to +;;; LETs. ;;; -;;; We flush all arguments to Call that correspond to unreferenced variables -;;; in Fun. We leave NILs in the Combination-Args so that the remaining args -;;; still match up with their vars. +;;; We flush all arguments to CALL that correspond to unreferenced +;;; variables in FUN. We leave NILs in the COMBINATION-ARGS so that +;;; the remaining args still match up with their vars. ;;; ;;; We also apply the declared variable type assertion to the argument ;;; continuations. @@ -46,17 +47,19 @@ (values)) -;;; This function handles merging the tail sets if Call is potentially -;;; tail-recursive, and is a call to a function with a different TAIL-SET than -;;; Call's Fun. This must be called whenever we alter IR1 so as to place a -;;; local call in what might be a TR context. Note that any call which returns -;;; its value to a RETURN is considered potentially TR, since any implicit -;;; MV-PROG1 might be optimized away. -;;; -;;; We destructively modify the set for the calling function to represent both, -;;; and then change all the functions in callee's set to reference the first. -;;; If we do merge, we reoptimize the RETURN-RESULT continuation to cause -;;; IR1-OPTIMIZE-RETURN to recompute the tail set type. +;;; This function handles merging the tail sets if CALL is potentially +;;; tail-recursive, and is a call to a function with a different +;;; TAIL-SET than CALL's FUN. This must be called whenever we alter +;;; IR1 so as to place a local call in what might be a tail-recursive +;;; context. Note that any call which returns its value to a RETURN is +;;; considered potentially tail-recursive, since any implicit MV-PROG1 +;;; might be optimized away. +;;; +;;; We destructively modify the set for the calling function to +;;; represent both, and then change all the functions in callee's set +;;; to reference the first. If we do merge, we reoptimize the +;;; RETURN-RESULT continuation to cause IR1-OPTIMIZE-RETURN to +;;; recompute the tail set type. (defun merge-tail-sets (call &optional (new-fun (combination-lambda call))) (declare (type basic-combination call) (type clambda new-fun)) (let ((return (continuation-dest (node-cont call)))) @@ -95,10 +98,10 @@ ;;;; external entry point creation -;;; Return a Lambda form that can be used as the definition of the XEP +;;; Return a LAMBDA form that can be used as the definition of the XEP ;;; for FUN. ;;; -;;; If FUN is a lambda, then we check the number of arguments +;;; If FUN is a LAMBDA, then we check the number of arguments ;;; (conditional on policy) and call FUN with all the arguments. ;;; ;;; If FUN is an OPTIONAL-DISPATCH, then we dispatch off of the number @@ -106,7 +109,7 @@ ;;; calling the entry with the appropriate prefix of the passed ;;; arguments. ;;; -;;; If there is a more arg, then there are a couple of optimizations +;;; If there is a &MORE arg, then there are a couple of optimizations ;;; that we make (more for space than anything else): ;;; -- If MIN-ARGS is 0, then we make the more entry a T clause, since ;;; no argument count error is possible. @@ -118,7 +121,7 @@ ;;; compared to the cost of everything else going on. ;;; ;;; Note that if policy indicates it, argument type declarations in -;;; Fun will be verified. Since nothing is known about the type of the +;;; FUN will be verified. Since nothing is known about the type of the ;;; XEP arg vars, type checks will be emitted when the XEP's arg vars ;;; are passed to the actual function. (defun make-xep-lambda (fun) @@ -130,7 +133,7 @@ (temps (make-gensym-list (length (lambda-vars fun))))) `(lambda (,n-supplied ,@temps) (declare (type index ,n-supplied)) - ,(if (policy nil (zerop safety)) + ,(if (policy *lexenv* (zerop safety)) `(declare (ignore ,n-supplied)) `(%verify-argument-count ,n-supplied ,nargs)) (%funcall ,fun ,@temps)))) @@ -192,12 +195,12 @@ (local-call-analyze-1 (optional-dispatch-more-entry fun))))) res))) -;;; Notice a Ref that is not in a local-call context. If the Ref is +;;; Notice a REF that is not in a local-call context. If the REF is ;;; already to an XEP, then do nothing, otherwise change it to the ;;; XEP, making an XEP if necessary. ;;; -;;; If Ref is to a special :Cleanup or :Escape function, then we treat -;;; it as though it was not an XEP reference (i.e. leave it alone.) +;;; If REF is to a special :CLEANUP or :ESCAPE function, then we treat +;;; it as though it was not an XEP reference (i.e. leave it alone). (defun reference-entry-point (ref) (declare (type ref ref)) (let ((fun (ref-leaf ref))) @@ -206,7 +209,7 @@ (change-ref-leaf ref (or (functional-entry-function fun) (make-external-entry-point fun)))))) -;;; Attempt to convert all references to Fun to local calls. The +;;; Attempt to convert all references to FUN to local calls. The ;;; reference must be the function for a call, and the function ;;; continuation must be used only once, since otherwise we cannot be ;;; sure what function is to be called. The call continuation would be @@ -217,7 +220,7 @@ ;;; function as an entry-point, creating a new XEP if necessary. We ;;; don't try to convert calls that are in error (:ERROR kind.) ;;; -;;; This is broken off from Local-Call-Analyze so that people can +;;; This is broken off from LOCAL-CALL-ANALYZE so that people can ;;; force analysis of newly introduced calls. Note that we don't do ;;; LET conversion here. (defun local-call-analyze-1 (fun) @@ -241,16 +244,16 @@ (values)) -;;; We examine all New-Functions in component, attempting to convert +;;; We examine all NEW-FUNCTIONS in component, attempting to convert ;;; calls into local calls when it is legal. We also attempt to -;;; convert each lambda to a LET. LET conversion is also triggered by +;;; convert each LAMBDA to a LET. LET conversion is also triggered by ;;; deletion of a function reference, but functions that start out ;;; eligible for conversion must be noticed sometime. ;;; ;;; Note that there is a lot of action going on behind the scenes ;;; here, triggered by reference deletion. In particular, the ;;; COMPONENT-LAMBDAS are being hacked to remove newly deleted and let -;;; converted lambdas, so it is important that the lambda is added to +;;; converted LAMBDAs, so it is important that the LAMBDA is added to ;;; the COMPONENT-LAMBDAS when it is. Also, the ;;; COMPONENT-NEW-FUNCTIONS may contain all sorts of drivel, since it ;;; is not updated when we delete functions, etc. Only @@ -278,7 +281,24 @@ (values)) -;;; If policy is auspicious, CALL is not in an XEP, and we don't seem +(defun local-call-analyze-until-done (clambdas) + (loop + (let ((did-something nil)) + (dolist (clambda clambdas) + (let* ((component (block-component (node-block (lambda-bind clambda)))) + (*all-components* (list component))) + ;; The original CMU CL code seemed to implicitly assume that + ;; COMPONENT is the only one here. Let's make that explicit. + (aver (= 1 (length (functional-components clambda)))) + (aver (eql component (first (functional-components clambda)))) + (when (component-new-functions component) + (setf did-something t) + (local-call-analyze component)))) + (unless did-something + (return)))) + (values)) + +;;; If policy is auspicious and CALL is not in an XEP and we don't seem ;;; to be in an infinite recursive loop, then change the reference to ;;; reference a fresh copy. We return whichever function we decide to ;;; reference. @@ -286,7 +306,6 @@ (if (and (policy call (and (>= speed space) (>= speed compilation-speed))) (not (eq (functional-kind (node-home-lambda call)) :external)) - (not *converting-for-interpreter*) (inline-expansion-ok call)) (with-ir1-environment call (let* ((*lexenv* (functional-lexenv fun)) @@ -308,23 +327,24 @@ fun)))) fun)) -;;; Dispatch to the appropriate function to attempt to convert a call. Ref -;;; most be a reference to a FUNCTIONAL. This is called in IR1 optimize as -;;; well as in local call analysis. If the call is is already :Local, we do -;;; nothing. If the call is already scheduled for deletion, also do nothing -;;; (in addition to saving time, this also avoids some problems with optimizing -;;; collections of functions that are partially deleted.) +;;; Dispatch to the appropriate function to attempt to convert a call. +;;; REF must be a reference to a FUNCTIONAL. This is called in IR1 +;;; optimize as well as in local call analysis. If the call is is +;;; already :LOCAL, we do nothing. If the call is already scheduled +;;; for deletion, also do nothing (in addition to saving time, this +;;; also avoids some problems with optimizing collections of functions +;;; that are partially deleted.) ;;; -;;; This is called both before and after FIND-INITIAL-DFO runs. When called -;;; on a :INITIAL component, we don't care whether the caller and callee are in -;;; the same component. Afterward, we must stick with whatever component -;;; division we have chosen. +;;; This is called both before and after FIND-INITIAL-DFO runs. When +;;; called on a :INITIAL component, we don't care whether the caller +;;; and callee are in the same component. Afterward, we must stick +;;; with whatever component division we have chosen. ;;; -;;; Before attempting to convert a call, we see whether the function is -;;; supposed to be inline expanded. Call conversion proceeds as before -;;; after any expansion. +;;; Before attempting to convert a call, we see whether the function +;;; is supposed to be inline expanded. Call conversion proceeds as +;;; before after any expansion. ;;; -;;; We bind *Compiler-Error-Context* to the node for the call so that +;;; We bind *COMPILER-ERROR-CONTEXT* to the node for the call so that ;;; warnings will get the right context. (defun convert-call-if-possible (ref call) (declare (type ref ref) (type basic-combination call)) @@ -336,7 +356,7 @@ (block-delete-p block) (eq (functional-kind (block-home-lambda block)) :deleted) (member (functional-kind original-fun) - '(:top-level-xep :deleted)) + '(:toplevel-xep :deleted)) (not (or (eq (component-kind component) :initial) (eq (block-component (node-block @@ -649,36 +669,87 @@ (link-blocks call-block bind-block) next-block))) +;;; Remove FUN from the tail set of anything it used to be in the +;;; same set as; but leave FUN with a valid tail set value of +;;; its own, for the benefit of code which might try to pull +;;; something out of it (e.g. return type). +(defun depart-from-tail-set (fun) + ;; Until sbcl-0.pre7.37.flaky5.2, we did + ;; (LET ((TAILS (LAMBDA-TAIL-SET FUN))) + ;; (SETF (TAIL-SET-FUNCTIONS TAILS) + ;; (DELETE FUN (TAIL-SET-FUNCTIONS TAILS)))) + ;; (SETF (LAMBDA-TAIL-SET FUN) NIL) + ;; here. Apparently the idea behind the (SETF .. NIL) was that since + ;; TAIL-SET-FUNCTIONS no longer thinks we're in the tail set, it's + ;; inconsistent, and perhaps unsafe, for us to think we're in the + ;; tail set. Unfortunately.. + ;; + ;; The (SETF .. NIL) caused problems in sbcl-0.pre7.37.flaky5.2 when + ;; I was trying to get Python to emit :EXTERNAL LAMBDAs directly + ;; (instead of only being able to emit funny little :TOPLEVEL stubs + ;; which you called in order to get the address of an external LAMBDA): + ;; the external function was defined in terms of internal function, + ;; which was LET-converted, and then things blew up downstream when + ;; FINALIZE-XEP-DEFINITION tried to find out its DEFINED-TYPE from + ;; the now-NILed-out TAIL-SET. So.. + ;; + ;; To deal with this problem, we no longer NIL out + ;; (LAMBDA-TAIL-SET FUN) here. Instead: + ;; * If we're the only function in TAIL-SET-FUNCTIONS, it should + ;; be safe to leave ourself linked to it, and it to you. + ;; * If there are other functions in TAIL-SET-FUNCTIONS, then we're + ;; afraid of future optimizations on those functions causing + ;; the TAIL-SET object no longer to be valid to describe our + ;; return value. Thus, we delete ourselves from that object; + ;; but we save a newly-allocated tail-set, derived from the old + ;; one, for ourselves, for the use of later code (e.g. + ;; FINALIZE-XEP-DEFINITION) which might want to + ;; know about our return type. + (let* ((old-tail-set (lambda-tail-set fun)) + (old-tail-set-functions (tail-set-functions old-tail-set))) + (unless (= 1 (length old-tail-set-functions)) + (setf (tail-set-functions old-tail-set) + (delete fun old-tail-set-functions)) + (let ((new-tail-set (copy-tail-set old-tail-set))) + (setf (lambda-tail-set fun) new-tail-set + (tail-set-functions new-tail-set) (list fun))))) + ;; The documentation on TAIL-SET-INFO doesn't tell whether it could + ;; remain valid in this case, so we nuke it on the theory that + ;; missing information tends to be less dangerous than incorrect + ;; information. + (setf (tail-set-info (lambda-tail-set fun)) nil)) + ;;; Handle the environment semantics of LET conversion. We add the -;;; lambda and its LETs to lets for the CALL's home function. We merge +;;; lambda and its LETs to LETs for the CALL's home function. We merge ;;; the calls for FUN with the calls for the home function, removing -;;; FUN in the process. We also merge the Entries. +;;; FUN in the process. We also merge the ENTRIES. ;;; ;;; We also unlink the function head from the component head and set ;;; COMPONENT-REANALYZE to true to indicate that the DFO should be ;;; recomputed. (defun merge-lets (fun call) + (declare (type clambda fun) (type basic-combination call)) + (let ((component (block-component (node-block call)))) (unlink-blocks (component-head component) (node-block (lambda-bind fun))) (setf (component-lambdas component) (delete fun (component-lambdas component))) (setf (component-reanalyze component) t)) (setf (lambda-call-lexenv fun) (node-lexenv call)) - (let ((tails (lambda-tail-set fun))) - (setf (tail-set-functions tails) - (delete fun (tail-set-functions tails)))) - (setf (lambda-tail-set fun) nil) + + (depart-from-tail-set fun) + (let* ((home (node-home-lambda call)) - (home-env (lambda-environment home))) + (home-env (lambda-physenv home))) (push fun (lambda-lets home)) (setf (lambda-home fun) home) - (setf (lambda-environment fun) home-env) + (setf (lambda-physenv fun) home-env) (let ((lets (lambda-lets fun))) (dolist (let lets) (setf (lambda-home let) home) - (setf (lambda-environment let) home-env)) + (setf (lambda-physenv let) home-env)) (setf (lambda-lets home) (nconc lets (lambda-lets home))) (setf (lambda-lets fun) ())) @@ -690,6 +761,7 @@ (setf (lambda-entries home) (nconc (lambda-entries fun) (lambda-entries home))) (setf (lambda-entries fun) ())) + (values)) ;;; Handle the value semantics of LET conversion. Delete FUN's return @@ -783,14 +855,15 @@ ;;; We do different things depending on whether the caller and callee ;;; have returns left: -;;; -- If the callee has no return we just do MOVE-LET-CALL-CONT. Either -;;; the function doesn't return, or all returns are via tail-recursive -;;; local calls. -;;; -- If CALL is a non-tail call, or if both have returns, then we -;;; delete the callee's return, move its uses to the call's result -;;; continuation, and transfer control to the appropriate return point. -;;; -- If the callee has a return, but the caller doesn't, then we move the -;;; return to the caller. +;;; -- If the callee has no return we just do MOVE-LET-CALL-CONT. +;;; Either the function doesn't return, or all returns are via +;;; tail-recursive local calls. +;;; -- If CALL is a non-tail call, or if both have returns, then +;;; we delete the callee's return, move its uses to the call's +;;; result continuation, and transfer control to the appropriate +;;; return point. +;;; -- If the callee has a return, but the caller doesn't, then we +;;; move the return to the caller. (defun move-return-stuff (fun call next-block) (declare (type clambda fun) (type basic-combination call) (type (or cblock null) next-block)) @@ -814,7 +887,7 @@ ;;; Actually do LET conversion. We call subfunctions to do most of the ;;; work. We change the CALL's cont to be the continuation heading the ;;; bind block, and also do REOPTIMIZE-CONTINUATION on the args and -;;; Cont so that let-specific IR1 optimizations get a chance. We blow +;;; Cont so that LET-specific IR1 optimizations get a chance. We blow ;;; away any entry for the function in *FREE-FUNCTIONS* so that nobody ;;; will create new reference to it. (defun let-convert (fun call) @@ -873,7 +946,8 @@ (not (functional-entry-function fun))) (let* ((ref-cont (node-cont (first refs))) (dest (continuation-dest ref-cont))) - (when (and (basic-combination-p dest) + (when (and dest + (basic-combination-p dest) (eq (basic-combination-fun dest) ref-cont) (eq (basic-combination-kind dest) :local) (not (block-delete-p (node-block dest))) @@ -964,7 +1038,9 @@ (call-fun nil)) (when (and (dolist (ref (leaf-refs fun) t) (let ((dest (continuation-dest (node-cont ref)))) - (when (block-delete-p (node-block dest)) (return nil)) + (when (or (not dest) + (block-delete-p (node-block dest))) + (return nil)) (let ((home (node-home-lambda ref))) (unless (eq home fun) (when call-fun (return nil))