(in-package "SB!C")
-(file-comment
- "$Header$")
-
-;;; 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.
(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))))
\f
;;;; external entry point creation
-;;; Return a Lambda form that can be used as the definition of the XEP for Fun.
+;;; 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 (conditional
-;;; on policy) and call Fun with all the 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 of
-;;; supplied arguments by doing do an = test for each entry-point, calling the
-;;; entry with the appropriate prefix of the passed arguments.
+;;; If FUN is an OPTIONAL-DISPATCH, then we dispatch off of the number
+;;; of supplied arguments by doing do an = test for each entry-point,
+;;; calling the entry with the appropriate prefix of the passed
+;;; arguments.
;;;
-;;; 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.
-;;; -- We can omit the = clause for the last entry-point, allowing the case of
-;;; 0 more args to fall through to the more entry.
+;;; 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.
+;;; -- We can omit the = clause for the last entry-point, allowing the
+;;; case of 0 more args to fall through to the more entry.
;;;
-;;; We don't bother to policy conditionalize wrong arg errors in optional
-;;; dispatches, since the additional overhead is negligible compared to the
-;;; other hair going down.
+;;; We don't bother to policy conditionalize wrong arg errors in
+;;; optional dispatches, since the additional overhead is negligible
+;;; 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 XEP arg vars,
-;;; type checks will be emitted when the XEP's arg vars are passed to the
-;;; actual function.
+;;; Note that if policy indicates it, argument type declarations in
+;;; 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)
(declare (type functional fun))
(etypecase fun
(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))))
(entries `((= ,n-supplied ,n)
(%funcall ,(first eps) ,@(subseq temps 0 n)))))
`(lambda (,n-supplied ,@temps)
- ;; FIXME: Make sure that INDEX type distinguishes between target
- ;; and host. (Probably just make the SB!XC:DEFTYPE different from
- ;; CL:DEFTYPE.)
+ ;; FIXME: Make sure that INDEX type distinguishes between
+ ;; target and host. (Probably just make the SB!XC:DEFTYPE
+ ;; different from CL:DEFTYPE.)
(declare (type index ,n-supplied))
(cond
,@(if more (butlast (entries)) (entries))
,@(when more
- `((,(if (zerop min) 't `(>= ,n-supplied ,max))
+ `((,(if (zerop min) t `(>= ,n-supplied ,max))
,(let ((n-context (gensym))
(n-count (gensym)))
`(multiple-value-bind (,n-context ,n-count)
(t
(%argument-count-error ,n-supplied)))))))))
-;;; Make an external entry point (XEP) for Fun and return it. We
-;;; convert the result of Make-XEP-Lambda in the correct environment,
-;;; then associate this lambda with Fun as its XEP. After the
+;;; Make an external entry point (XEP) for FUN and return it. We
+;;; convert the result of MAKE-XEP-LAMBDA in the correct environment,
+;;; then associate this lambda with FUN as its XEP. After the
;;; conversion, we iterate over the function's associated lambdas,
;;; redoing local call analysis so that the XEP calls will get
-;;; converted. We also bind *LEXENV* to change the compilation policy
-;;; over to the interface policy.
+;;; converted.
;;;
-;;; We set Reanalyze and Reoptimize in the component, just in case we
+;;; We set REANALYZE and REOPTIMIZE in the component, just in case we
;;; discover an XEP after the initial local call analyze pass.
(defun make-external-entry-point (fun)
(declare (type functional fun))
- (assert (not (functional-entry-function fun)))
+ (aver (not (functional-entry-function fun)))
(with-ir1-environment (lambda-bind (main-entry fun))
- (let* ((*lexenv* (make-lexenv :cookie (make-interface-cookie *lexenv*)))
- (res (ir1-convert-lambda (make-xep-lambda fun))))
- (setf (functional-kind res) :external)
- (setf (leaf-ever-used res) t)
- (setf (functional-entry-function res) fun)
- (setf (functional-entry-function fun) res)
- (setf (component-reanalyze *current-component*) t)
- (setf (component-reoptimize *current-component*) t)
+ (let ((res (ir1-convert-lambda (make-xep-lambda fun)
+ :debug-name (debug-namify
+ "XEP for ~A"
+ (leaf-debug-name fun)))))
+ (setf (functional-kind res) :external
+ (leaf-ever-used res) t
+ (functional-entry-function res) fun
+ (functional-entry-function fun) res
+ (component-reanalyze *current-component*) t
+ (component-reoptimize *current-component*) t)
(etypecase fun
(clambda (local-call-analyze-1 fun))
(optional-dispatch
(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)))
(change-ref-leaf ref (or (functional-entry-function fun)
(make-external-entry-point fun))))))
\f
-;;; 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
;;; 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)
(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
(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.
(defun maybe-expand-local-inline (fun ref call)
- (if (and (policy call (>= speed space) (>= speed cspeed))
+ (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))
(won nil)
(res (catch 'local-call-lossage
(prog1
- (ir1-convert-lambda (functional-inline-expansion fun))
+ (ir1-convert-lambda (functional-inline-expansion
+ :source-name fun))
(setq won t)))))
(cond (won
(change-ref-leaf ref res)
(t
(let ((*compiler-error-context* call))
(compiler-note "couldn't inline expand because expansion ~
- calls this let-converted local function:~
+ calls this LET-converted local function:~
~% ~S"
- (leaf-name res)))
+ (leaf-debug-name res)))
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))
(let* ((block (node-block call))
(component (block-component block))
(original-fun (ref-leaf ref)))
- (assert (functional-p original-fun))
+ (aver (functional-p original-fun))
(unless (or (member (basic-combination-kind call) '(:local :error))
(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
(rest (leaf-refs original-fun)))
(setq fun (maybe-expand-local-inline fun ref call)))
- (assert (member (functional-kind fun)
- '(nil :escape :cleanup :optional)))
+ (aver (member (functional-kind fun)
+ '(nil :escape :cleanup :optional)))
(cond ((mv-combination-p call)
(convert-mv-call ref call fun))
((lambda-p fun)
;; but as long as we continue to use that policy, that's the
;; not our biggest problem.:-| When we fix that policy, this
;; should come back into compliance. (So fix that policy!)
+ ;; ..but..
+ ;; FIXME, continued: Except that section "3.2.2.3 Semantic
+ ;; Constraints" says that if it's within the same file, it's
+ ;; wrong. And we're in locall.lisp here, so it's probably
+ ;; (haven't checked this..) a call to something in the same
+ ;; file. So maybe it deserves a full warning anyway.
(compiler-warning
"function called with ~R argument~:P, but wants exactly ~R"
call-args nargs)
(setf (basic-combination-kind call) :error)))))
\f
-;;;; optional, more and keyword calls
+;;;; &OPTIONAL, &MORE and &KEYWORD calls
-;;; Similar to Convert-Lambda-Call, but deals with Optional-Dispatches. If
-;;; only fixed args are supplied, then convert a call to the correct entry
-;;; point. If keyword args are supplied, then dispatch to a subfunction. We
-;;; don't convert calls to functions that have a more (or rest) arg.
+;;; This is similar to CONVERT-LAMBDA-CALL, but deals with
+;;; OPTIONAL-DISPATCHes. If only fixed args are supplied, then convert
+;;; a call to the correct entry point. If &KEY args are supplied, then
+;;; dispatch to a subfunction. We don't convert calls to functions
+;;; that have a &MORE (or &REST) arg.
(defun convert-hairy-call (ref call fun)
(declare (type ref ref) (type combination call)
(type optional-dispatch fun))
(max-args (optional-dispatch-max-args fun))
(call-args (length (combination-args call))))
(cond ((< call-args min-args)
- ;; FIXME: ANSI requires in "3.2.5 Exceptional Situations in the
- ;; Compiler" that calling a function with "the wrong number of
- ;; arguments" be only a STYLE-ERROR. I think, though, that this
- ;; should only apply when the number of arguments is inferred
- ;; from a previous definition. If the number of arguments
- ;; is DECLAIMed, surely calling with the wrong number is a
- ;; real WARNING. As long as SBCL continues to use CMU CL's
- ;; non-ANSI DEFUN-is-a-DECLAIM policy, we're in violation here,
- ;; but as long as we continue to use that policy, that's the
- ;; not our biggest problem.:-| When we fix that policy, this
- ;; should come back into compliance. (So fix that policy!)
+ ;; FIXME: See FIXME note at the previous
+ ;; wrong-number-of-arguments warnings in this file.
(compiler-warning
"function called with ~R argument~:P, but wants at least ~R"
call-args min-args)
((optional-dispatch-more-entry fun)
(convert-more-call ref call fun))
(t
- ;; FIXME: ANSI requires in "3.2.5 Exceptional Situations in the
- ;; Compiler" that calling a function with "the wrong number of
- ;; arguments" be only a STYLE-ERROR. I think, though, that this
- ;; should only apply when the number of arguments is inferred
- ;; from a previous definition. If the number of arguments
- ;; is DECLAIMed, surely calling with the wrong number is a
- ;; real WARNING. As long as SBCL continues to use CMU CL's
- ;; non-ANSI DEFUN-is-a-DECLAIM policy, we're in violation here,
- ;; but as long as we continue to use that policy, that's the
- ;; not our biggest problem.:-| When we fix that policy, this
- ;; should come back into compliance. (So fix that policy!)
+ ;; FIXME: See FIXME note at the previous
+ ;; wrong-number-of-arguments warnings in this file.
(compiler-warning
"function called with ~R argument~:P, but wants at most ~R"
call-args max-args)
(dolist (ref (leaf-refs entry))
(convert-call-if-possible ref (continuation-dest (node-cont ref))))))
-;;; Use Convert-Hairy-Fun-Entry to convert a more-arg call to a known
-;;; function into a local call to the Main-Entry.
+;;; Use CONVERT-HAIRY-FUN-ENTRY to convert a &MORE-arg call to a known
+;;; function into a local call to the MAIN-ENTRY.
;;;
;;; First we verify that all keywords are constant and legal. If there
;;; aren't, then we warn the user and don't attempt to convert the call.
;;;
-;;; We massage the supplied keyword arguments into the order expected by the
-;;; main entry. This is done by binding all the arguments to the keyword call
-;;; to variables in the introduced lambda, then passing these values variables
-;;; in the correct order when calling the main entry. Unused arguments
-;;; (such as the keywords themselves) are discarded simply by not passing them
-;;; along.
+;;; We massage the supplied &KEY arguments into the order expected
+;;; by the main entry. This is done by binding all the arguments to
+;;; the keyword call to variables in the introduced lambda, then
+;;; passing these values variables in the correct order when calling
+;;; the main entry. Unused arguments (such as the keywords themselves)
+;;; are discarded simply by not passing them along.
;;;
-;;; If there is a rest arg, then we bundle up the args and pass them to LIST.
+;;; If there is a &REST arg, then we bundle up the args and pass them
+;;; to LIST.
(defun convert-more-call (ref call fun)
(declare (type ref ref) (type combination call) (type optional-dispatch fun))
(let* ((max (optional-dispatch-max-args fun))
(arglist (optional-dispatch-arglist fun))
(args (combination-args call))
(more (nthcdr max args))
- (flame (policy call (or (> speed brevity) (> space brevity))))
+ (flame (policy call (or (> speed inhibit-warnings)
+ (> space inhibit-warnings))))
(loser nil)
(temps (make-gensym-list max))
(more-temps (make-gensym-list (length more))))
(ignores dummy val)
(setq loser name)))
(let ((info (lambda-var-arg-info var)))
- (when (eq (arg-info-keyword info) name)
+ (when (eq (arg-info-key info) name)
(ignores dummy)
(supplied (cons var val))
(return)))))))
\f
;;;; LET conversion
;;;;
-;;;; Converting to a LET has differing significance to various parts of the
-;;;; compiler:
-;;;; -- The body of a LET is spliced in immediately after the corresponding
-;;;; combination node, making the control transfer explicit and allowing
-;;;; LETs to be mashed together into a single block. The value of the LET is
-;;;; delivered directly to the original continuation for the call,
-;;;; eliminating the need to propagate information from the dummy result
-;;;; continuation.
-;;;; -- As far as IR1 optimization is concerned, it is interesting in that
-;;;; there is only one expression that the variable can be bound to, and
-;;;; this is easily substitited for.
-;;;; -- LETs are interesting to environment analysis and to the back end
-;;;; because in most ways a LET can be considered to be "the same function"
-;;;; as its home function.
-;;;; -- LET conversion has dynamic scope implications, since control transfers
-;;;; within the same environment are local. In a local control transfer,
-;;;; cleanup code must be emitted to remove dynamic bindings that are no
-;;;; longer in effect.
-
-;;; Set up the control transfer to the called lambda. We split the call
-;;; block immediately after the call, and link the head of FUN to the call
-;;; block. The successor block after splitting (where we return to) is
-;;; returned.
-;;;
-;;; If the lambda is is a different component than the call, then we call
-;;; JOIN-COMPONENTS. This only happens in block compilation before
-;;; FIND-INITIAL-DFO.
+;;;; Converting to a LET has differing significance to various parts
+;;;; of the compiler:
+;;;; -- The body of a LET is spliced in immediately after the
+;;;; corresponding combination node, making the control transfer
+;;;; explicit and allowing LETs to be mashed together into a single
+;;;; block. The value of the LET is delivered directly to the
+;;;; original continuation for the call,eliminating the need to
+;;;; propagate information from the dummy result continuation.
+;;;; -- As far as IR1 optimization is concerned, it is interesting in
+;;;; that there is only one expression that the variable can be bound
+;;;; to, and this is easily substitited for.
+;;;; -- LETs are interesting to environment analysis and to the back
+;;;; end because in most ways a LET can be considered to be "the
+;;;; same function" as its home function.
+;;;; -- LET conversion has dynamic scope implications, since control
+;;;; transfers within the same environment are local. In a local
+;;;; control transfer, cleanup code must be emitted to remove
+;;;; dynamic bindings that are no longer in effect.
+
+;;; Set up the control transfer to the called lambda. We split the
+;;; call block immediately after the call, and link the head of FUN to
+;;; the call block. The successor block after splitting (where we
+;;; return to) is returned.
+;;;
+;;; If the lambda is is a different component than the call, then we
+;;; call JOIN-COMPONENTS. This only happens in block compilation
+;;; before FIND-INITIAL-DFO.
(defun insert-let-body (fun call)
(declare (type clambda fun) (type basic-combination call))
(let* ((call-block (node-block call))
(component (block-component call-block)))
(let ((fun-component (block-component bind-block)))
(unless (eq fun-component component)
- (assert (eq (component-kind component) :initial))
+ (aver (eq (component-kind component) :initial))
(join-components component fun-component)))
(let ((*current-component* component))
;; FIXME: Use PROPER-LIST-OF-LENGTH-P here, and look for other
;; uses of '=.*length' which could also be converted to use
;; PROPER-LIST-OF-LENGTH-P.
- (assert (= (length (block-succ call-block)) 1))
+ (aver (= (length (block-succ call-block)) 1))
(let ((next-block (first (block-succ call-block))))
(unlink-blocks call-block next-block)
(link-blocks call-block bind-block)
next-block)))
-;;; Handle the environment semantics of LET conversion. We add the 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.
+;;; 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
+;;; the calls for FUN with the calls for the home function, removing
+;;; 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.
+;;; 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) ()))
(setf (lambda-calls home)
- (nunion (lambda-calls fun)
- (delete fun (lambda-calls home))))
+ (delete fun (nunion (lambda-calls fun) (lambda-calls home))))
(setf (lambda-calls fun) ())
(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 node,
-;;; and change the control flow to transfer to Next-Block instead. Move all
-;;; the uses of the result continuation to Call's Cont.
+;;; Handle the value semantics of LET conversion. Delete FUN's return
+;;; node, and change the control flow to transfer to NEXT-BLOCK
+;;; instead. Move all the uses of the result continuation to CALL's
+;;; CONT.
;;;
-;;; If the actual continuation is only used by the let call, then we
-;;; intersect the type assertion on the dummy continuation with the assertion
-;;; for the actual continuation; in all other cases assertions on the dummy
-;;; continuation are lost.
+;;; If the actual continuation is only used by the LET call, then we
+;;; intersect the type assertion on the dummy continuation with the
+;;; assertion for the actual continuation; in all other cases
+;;; assertions on the dummy continuation are lost.
;;;
-;;; We also intersect the derived type of the call with the derived type of
-;;; all the dummy continuation's uses. This serves mainly to propagate
-;;; TRULY-THE through lets.
+;;; We also intersect the derived type of the CALL with the derived
+;;; type of all the dummy continuation's uses. This serves mainly to
+;;; propagate TRULY-THE through LETs.
(defun move-return-uses (fun call next-block)
(declare (type clambda fun) (type basic-combination call)
(type cblock next-block))
(substitute-continuation-uses cont result)))
(values))
-;;; Change all Cont for all the calls to Fun to be the start continuation
-;;; for the bind node. This allows the blocks to be joined if the caller count
-;;; ever goes to one.
+;;; Change all CONT for all the calls to FUN to be the start
+;;; continuation for the bind node. This allows the blocks to be
+;;; joined if the caller count ever goes to one.
(defun move-let-call-cont (fun)
(declare (type clambda fun))
(let ((new-cont (node-prev (lambda-bind fun))))
(add-continuation-use dest new-cont))))
(values))
-;;; We are converting Fun to be a let when the call is in a non-tail
-;;; position. Any previously tail calls in Fun are no longer tail calls, and
-;;; must be restored to normal calls which transfer to Next-Block (Fun's
-;;; return point.) We can't do this by DO-USES on the RETURN-RESULT, because
-;;; the return might have been deleted (if all calls were TR.)
+;;; We are converting FUN to be a LET when the call is in a non-tail
+;;; position. Any previously tail calls in FUN are no longer tail
+;;; calls, and must be restored to normal calls which transfer to
+;;; NEXT-BLOCK (FUN's return point.) We can't do this by DO-USES on
+;;; the RETURN-RESULT, because the return might have been deleted (if
+;;; all calls were TR.)
;;;
-;;; The called function might be an assignment in the case where we are
-;;; currently converting that function. In steady-state, assignments never
-;;; appear in the lambda-calls.
+;;; The called function might be an assignment in the case where we
+;;; are currently converting that function. In steady-state,
+;;; assignments never appear in the lambda-calls.
(defun unconvert-tail-calls (fun call next-block)
(dolist (called (lambda-calls fun))
(dolist (ref (leaf-refs called))
(add-continuation-use this-call cont)))
(:deleted)
(:assignment
- (assert (eq called fun))))))))
+ (aver (eq called fun))))))))
(values))
-;;; Deal with returning from a let or assignment that we are converting.
-;;; FUN is the function we are calling, CALL is a call to FUN, and NEXT-BLOCK
-;;; is the return point for a non-tail call, or NULL if call is a tail call.
-;;;
-;;; If the call is not a tail call, then we must do UNCONVERT-TAIL-CALLS, since
-;;; a tail call is a call which returns its value out of the enclosing non-let
-;;; function. When call is non-TR, we must convert it back to an ordinary
-;;; local call, since the value must be delivered to the receiver of CALL's
-;;; value.
-;;;
-;;; 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.
+;;; Deal with returning from a LET or assignment that we are
+;;; converting. FUN is the function we are calling, CALL is a call to
+;;; FUN, and NEXT-BLOCK is the return point for a non-tail call, or
+;;; NULL if call is a tail call.
+;;;
+;;; If the call is not a tail call, then we must do
+;;; UNCONVERT-TAIL-CALLS, since a tail call is a call which returns
+;;; its value out of the enclosing non-let function. When call is
+;;; non-TR, we must convert it back to an ordinary local call, since
+;;; the value must be delivered to the receiver of CALL's value.
+;;;
+;;; 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.
(defun move-return-stuff (fun call next-block)
(declare (type clambda fun) (type basic-combination call)
(type (or cblock null) next-block))
(move-return-uses fun call
(or next-block (node-block call-return)))))
(t
- (assert (node-tail-p call))
+ (aver (node-tail-p call))
(setf (lambda-return call-fun) return)
(setf (return-lambda return) call-fun))))
(move-let-call-cont fun)
(values))
;;; 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 away any entry for
-;;; the function in *FREE-FUNCTIONS* so that nobody will create new reference
-;;; to it.
+;;; 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
+;;; away any entry for the function in *FREE-FUNCTIONS* so that nobody
+;;; will create new reference to it.
(defun let-convert (fun call)
(declare (type clambda fun) (type basic-combination call))
(let ((next-block (if (node-tail-p call)
(reoptimize-continuation (node-cont call))
(values))
-;;; We also don't convert calls to named functions which appear in the initial
-;;; component, delaying this until optimization. This minimizes the likelyhood
-;;; that we well let-convert a function which may have references added due to
-;;; later local inline expansion
+;;; We also don't convert calls to named functions which appear in the
+;;; initial component, delaying this until optimization. This
+;;; minimizes the likelyhood that we well let-convert a function which
+;;; may have references added due to later local inline expansion
(defun ok-initial-convert-p (fun)
- (not (and (leaf-name fun)
+ (not (and (leaf-has-source-name-p fun)
(eq (component-kind
(block-component
(node-block (lambda-bind fun))))
:initial))))
;;; This function is called when there is some reason to believe that
-;;; the lambda Fun might be converted into a let. This is done after local
-;;; call analysis, and also when a reference is deleted. We only convert to a
-;;; let when the function is a normal local function, has no XEP, and is
-;;; referenced in exactly one local call. Conversion is also inhibited if the
-;;; only reference is in a block about to be deleted. We return true if we
-;;; converted.
-;;;
-;;; These rules may seem unnecessarily restrictive, since there are some
-;;; cases where we could do the return with a jump that don't satisfy these
-;;; requirements. The reason for doing things this way is that it makes the
-;;; concept of a let much more useful at the level of IR1 semantics. The
-;;; :ASSIGNMENT function kind provides another way to optimize calls to
-;;; single-return/multiple call functions.
-;;;
-;;; We don't attempt to convert calls to functions that have an XEP, since
-;;; we might be embarrassed later when we want to convert a newly discovered
-;;; local call. Also, see OK-INITIAL-CONVERT-P.
+;;; the lambda Fun might be converted into a let. This is done after
+;;; local call analysis, and also when a reference is deleted. We only
+;;; convert to a let when the function is a normal local function, has
+;;; no XEP, and is referenced in exactly one local call. Conversion is
+;;; also inhibited if the only reference is in a block about to be
+;;; deleted. We return true if we converted.
+;;;
+;;; These rules may seem unnecessarily restrictive, since there are
+;;; some cases where we could do the return with a jump that don't
+;;; satisfy these requirements. The reason for doing things this way
+;;; is that it makes the concept of a LET much more useful at the
+;;; level of IR1 semantics. The :ASSIGNMENT function kind provides
+;;; another way to optimize calls to single-return/multiple call
+;;; functions.
+;;;
+;;; We don't attempt to convert calls to functions that have an XEP,
+;;; since we might be embarrassed later when we want to convert a
+;;; newly discovered local call. Also, see OK-INITIAL-CONVERT-P.
(defun maybe-let-convert (fun)
(declare (type clambda fun))
(let ((refs (leaf-refs fun)))
(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)))
\f
;;;; tail local calls and assignments
-;;; Return T if there are no cleanups between Block1 and Block2, or if they
-;;; definitely won't generate any cleanup code. Currently we recognize lexical
-;;; entry points that are only used locally (if at all).
+;;; Return T if there are no cleanups between BLOCK1 and BLOCK2, or if
+;;; they definitely won't generate any cleanup code. Currently we
+;;; recognize lexical entry points that are only used locally (if at
+;;; all).
(defun only-harmless-cleanups (block1 block2)
(declare (type cblock block1 block2))
(or (eq block1 block2)
(return nil)))
(t (return nil)))))))
-;;; If a potentially TR local call really is TR, then convert it to jump
-;;; directly to the called function. We also call MAYBE-CONVERT-TO-ASSIGNMENT.
-;;; The first value is true if we tail-convert. The second is the value of
-;;; M-C-T-A. We can switch the succesor (potentially deleting the RETURN node)
-;;; unless:
+;;; If a potentially TR local call really is TR, then convert it to
+;;; jump directly to the called function. We also call
+;;; MAYBE-CONVERT-TO-ASSIGNMENT. The first value is true if we
+;;; tail-convert. The second is the value of M-C-T-A. We can switch
+;;; the succesor (potentially deleting the RETURN node) unless:
;;; -- The call has already been converted.
;;; -- The call isn't TR (some implicit MV PROG1.)
-;;; -- The call is in an XEP (thus we might decide to make it non-tail so that
-;;; we can use known return inside the component.)
-;;; -- There is a change in the cleanup between the call in the return, so we
-;;; might need to introduce cleanup code.
+;;; -- The call is in an XEP (thus we might decide to make it non-tail
+;;; so that we can use known return inside the component.)
+;;; -- There is a change in the cleanup between the call in the return,
+;;; so we might need to introduce cleanup code.
(defun maybe-convert-tail-local-call (call)
(declare (type combination call))
(let ((return (continuation-dest (node-cont call))))
- (assert (return-p return))
+ (aver (return-p return))
(when (and (not (node-tail-p call))
(immediately-used-p (return-result return) call)
(not (eq (functional-kind (node-home-lambda call))
(link-blocks block (node-block (lambda-bind fun)))
(values t (maybe-convert-to-assignment fun))))))
-;;; Called when we believe it might make sense to convert Fun to an
-;;; assignment. All this function really does is determine when a function
-;;; with more than one call can still be combined with the calling function's
-;;; environment. We can convert when:
+;;; This is called when we believe it might make sense to convert Fun
+;;; to an assignment. All this function really does is determine when
+;;; a function with more than one call can still be combined with the
+;;; calling function's environment. We can convert when:
;;; -- The function is a normal, non-entry function, and
-;;; -- Except for one call, all calls must be tail recursive calls in the
-;;; called function (i.e. are self-recursive tail calls)
+;;; -- Except for one call, all calls must be tail recursive calls
+;;; in the called function (i.e. are self-recursive tail calls)
;;; -- OK-INITIAL-CONVERT-P is true.
;;;
-;;; There may be one outside call, and it need not be tail-recursive. Since
-;;; all tail local calls have already been converted to direct transfers, the
-;;; only control semantics needed are to splice in the body at the non-tail
-;;; call. If there is no non-tail call, then we need only merge the
-;;; environments. Both cases are handled by LET-CONVERT.
+;;; There may be one outside call, and it need not be tail-recursive.
+;;; Since all tail local calls have already been converted to direct
+;;; transfers, the only control semantics needed are to splice in the
+;;; body at the non-tail call. If there is no non-tail call, then we
+;;; need only merge the environments. Both cases are handled by
+;;; LET-CONVERT.
;;;
-;;; ### It would actually be possible to allow any number of outside calls as
-;;; long as they all return to the same place (i.e. have the same conceptual
-;;; continuation.) A special case of this would be when all of the outside
-;;; calls are tail recursive.
+;;; ### It would actually be possible to allow any number of outside
+;;; calls as long as they all return to the same place (i.e. have the
+;;; same conceptual continuation.) A special case of this would be
+;;; when all of the outside calls are tail recursive.
(defun maybe-convert-to-assignment (fun)
(declare (type clambda fun))
(when (and (not (functional-kind fun))
(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))