X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fcheckgen.lisp;h=b461851c8978b1cd9145b995f85b4a3498985222;hb=0dda5090b6c16a641000b4eb2dcd479f39b784ca;hp=129c7547b8e17f53b59b59a5b8b721055c2ade15;hpb=aebbc5aad31f7e55930c996a8c54f0a135e00894;p=sbcl.git diff --git a/src/compiler/checkgen.lisp b/src/compiler/checkgen.lisp index 129c754..b461851 100644 --- a/src/compiler/checkgen.lisp +++ b/src/compiler/checkgen.lisp @@ -27,15 +27,15 @@ (defun fun-guessed-cost (name) (declare (symbol name)) (let ((info (info :function :info name)) - (call-cost (template-cost (template-or-lose 'call-named)))) + (call-cost (template-cost (template-or-lose 'call-named)))) (if info - (let ((templates (fun-info-templates info))) - (if templates - (template-cost (first templates)) - (case name - (null (template-cost (template-or-lose 'if-eq))) - (t call-cost)))) - call-cost))) + (let ((templates (fun-info-templates info))) + (if templates + (template-cost (first templates)) + (case name + (null (template-cost (template-or-lose 'if-eq))) + (t call-cost)))) + call-cost))) ;;; Return some sort of guess for the cost of doing a test against ;;; TYPE. The result need not be precise as long as it isn't way out @@ -43,35 +43,61 @@ ;;; templates in the VM definition. (defun type-test-cost (type) (declare (type ctype type)) - (or (let ((check (type-check-template type))) - (if check - (template-cost check) - (let ((found (cdr (assoc type *backend-type-predicates* - :test #'type=)))) - (if found - (+ (fun-guessed-cost found) (fun-guessed-cost 'eq)) - nil)))) + (or (when (eq type *universal-type*) + 0) + (when (eq type *empty-type*) + 0) + (let ((check (type-check-template type))) + (if check + (template-cost check) + (let ((found (cdr (assoc type *backend-type-predicates* + :test #'type=)))) + (if found + (+ (fun-guessed-cost found) (fun-guessed-cost 'eq)) + nil)))) (typecase type - (compound-type - (reduce #'+ (compound-type-types type) :key 'type-test-cost)) - (member-type - (* (length (member-type-members type)) - (fun-guessed-cost 'eq))) - (numeric-type - (* (if (numeric-type-complexp type) 2 1) - (fun-guessed-cost - (if (csubtypep type (specifier-type 'fixnum)) 'fixnump 'numberp)) - (+ 1 - (if (numeric-type-low type) 1 0) - (if (numeric-type-high type) 1 0)))) - (cons-type - (+ (type-test-cost (specifier-type 'cons)) - (fun-guessed-cost 'car) - (type-test-cost (cons-type-car-type type)) - (fun-guessed-cost 'cdr) - (type-test-cost (cons-type-cdr-type type)))) - (t - (fun-guessed-cost 'typep))))) + (compound-type + (reduce #'+ (compound-type-types type) :key 'type-test-cost)) + (member-type + (* (member-type-size type) + (fun-guessed-cost 'eq))) + (numeric-type + (* (if (numeric-type-complexp type) 2 1) + (fun-guessed-cost + (if (csubtypep type (specifier-type 'fixnum)) 'fixnump 'numberp)) + (+ 1 + (if (numeric-type-low type) 1 0) + (if (numeric-type-high type) 1 0)))) + (cons-type + (+ (type-test-cost (specifier-type 'cons)) + (fun-guessed-cost 'car) + (type-test-cost (cons-type-car-type type)) + (fun-guessed-cost 'cdr) + (type-test-cost (cons-type-cdr-type type)))) + (t + (fun-guessed-cost 'typep))))) + +(defun weaken-integer-type (type) + (cond ((union-type-p type) + (let* ((types (union-type-types type)) + (one (pop types)) + (low (numeric-type-low one)) + (high (numeric-type-high one))) + (flet ((maximize (bound) + (if (and bound high) + (setf high (max high bound)) + (setf high nil))) + (minimize (bound) + (if (and bound low) + (setf low (min low bound)) + (setf low nil)))) + (dolist (a types) + (minimize (numeric-type-low a)) + (maximize (numeric-type-high a)))) + (specifier-type `(integer ,(or low '*) ,(or high '*))))) + (t + (aver (integer-type-p type)) + type))) (defun-cached (weaken-type :hash-bits 8 @@ -79,40 +105,54 @@ (logand (type-hash-value x) #xFF))) ((type eq)) (declare (type ctype type)) - (let ((min-cost (type-test-cost type)) - (min-type type) - (found-super nil)) - (dolist (x *backend-type-predicates*) - (let ((stype (car x))) - (when (and (csubtypep type stype) - (not (union-type-p stype))) - (let ((stype-cost (type-test-cost stype))) - (when (or (< stype-cost min-cost) - (type= stype type)) - ;; If the supertype is equal in cost to the type, we - ;; prefer the supertype. This produces a closer - ;; approximation of the right thing in the presence of - ;; poor cost info. - (setq found-super t - min-type stype - min-cost stype-cost)))))) - (if found-super - min-type - *universal-type*))) + (cond ((named-type-p type) + type) + ((csubtypep type (specifier-type 'integer)) + ;; KLUDGE: Simple range checks are not that expensive, and we *don't* + ;; want to accidentally lose eg. array bounds checks due to weakening, + ;; so for integer types we simply collapse all ranges into one. + (weaken-integer-type type)) + (t + (let ((min-cost (type-test-cost type)) + (min-type type) + (found-super nil)) + (dolist (x *backend-type-predicates*) + (let* ((stype (car x)) + (samep (type= stype type))) + (when (or samep + (and (csubtypep type stype) + (not (union-type-p stype)))) + (let ((stype-cost (type-test-cost stype))) + (when (or (< stype-cost min-cost) + samep) + ;; If the supertype is equal in cost to the type, we + ;; prefer the supertype. This produces a closer + ;; approximation of the right thing in the presence of + ;; poor cost info. + (setq found-super t + min-type stype + min-cost stype-cost)))))) + ;; This used to return the *UNIVERSAL-TYPE* if no supertype was found, + ;; but that's too liberal: it's far too easy for the user to create + ;; a union type (which are excluded above), and then trick the compiler + ;; into trusting the union type... and finally ending up corrupting the + ;; heap once a bad object sneaks past the missing type check. + (if found-super + min-type + type))))) (defun weaken-values-type (type) (declare (type ctype type)) (cond ((eq type *wild-type*) type) - ((values-type-p type) + ((not (values-type-p type)) + (weaken-type type)) + (t (make-values-type :required (mapcar #'weaken-type (values-type-required type)) :optional (mapcar #'weaken-type (values-type-optional type)) :rest (acond ((values-type-rest type) - (weaken-type it)) - ((values-type-keyp type) - *universal-type*)))) - (t (weaken-type type)))) + (weaken-type it))))))) ;;;; checking strategy determination @@ -133,78 +173,77 @@ (declare (type ctype type)) (multiple-value-bind (res count) (values-types type) (values (mapcar (lambda (type) - (if (fun-type-p type) - (specifier-type 'function) - type)) - res) - count))) + (if (fun-type-p type) + (specifier-type 'function) + type)) + res) + count))) ;;; Switch to disable check complementing, for evaluation. (defvar *complement-type-checks* t) -;;; CONT is a continuation we are doing a type check on and TYPES is a -;;; list of types that we are checking its values against. If we have -;;; proven that CONT generates a fixed number of values, then for each +;;; LVAR is an lvar we are doing a type check on and TYPES is a list +;;; of types that we are checking its values against. If we have +;;; proven that LVAR generates a fixed number of values, then for each ;;; value, we check whether it is cheaper to then difference between ;;; the proven type and the corresponding type in TYPES. If so, we opt ;;; for a :HAIRY check with that test negated. Otherwise, we try to do ;;; a simple test, and if that is impossible, we do a hairy test with ;;; non-negated types. If true, FORCE-HAIRY forces a hairy type check. -;;; -;;; When doing a non-negated check, we call MAYBE-WEAKEN-CHECK to -;;; weaken the test to a convenient supertype (conditional on policy.) -;;; If SPEED is 3, or DEBUG-INFO is not particularly important (DEBUG -;;; <= 1), then we allow weakened checks to be simple, resulting in -;;; less informative error messages, but saving space and possibly -;;; time. -;;; -;;; FIXME: I don't quite understand this, but it looks as though -;;; that means type checks are weakened when SPEED=3 regardless of -;;; the SAFETY level, which is not the right thing to do. -(defun maybe-negate-check (cont types original-types force-hairy) - (declare (type continuation cont) (list types)) - (multiple-value-bind (ptypes count) - (no-fun-values-types (continuation-proven-type cont)) - (if (eq count :unknown) - (if (and (every #'type-check-template types) (not force-hairy)) - (values :simple types) - (values :hairy (mapcar (lambda (x) (list nil x x)) types))) - (let ((res (mapcar (lambda (p c a) - (let ((diff (type-difference p c))) - (if (and diff - (< (type-test-cost diff) - (type-test-cost c)) - *complement-type-checks*) - (list t diff a) - (list nil c a)))) - ptypes types original-types))) - (cond ((or force-hairy (find-if #'first res)) - (values :hairy res)) - ((every #'type-check-template types) - (values :simple types)) - (t - (values :hairy res))))))) - -;;; Determines whether CONT's assertion is: +(defun maybe-negate-check (lvar types original-types force-hairy n-required) + (declare (type lvar lvar) (list types original-types)) + (let ((ptypes (values-type-out (lvar-derived-type lvar) (length types)))) + (multiple-value-bind (hairy-res simple-res) + (loop for p in ptypes + and c in types + and a in original-types + and i from 0 + for cc = (if (>= i n-required) + (type-union c (specifier-type 'null)) + c) + for diff = (type-difference p cc) + collect (if (and diff + (< (type-test-cost diff) + (type-test-cost cc)) + *complement-type-checks*) + (list t diff a) + (list nil cc a)) + into hairy-res + collect cc into simple-res + finally (return (values hairy-res simple-res))) + (cond ((or force-hairy (find-if #'first hairy-res)) + (values :hairy hairy-res)) + ((every #'type-check-template simple-res) + (values :simple simple-res)) + (t + (values :hairy hairy-res)))))) + +;;; Determines whether CAST's assertion is: ;;; -- checkable by the back end (:SIMPLE), or -;;; -- not checkable by the back end, but checkable via an explicit +;;; -- not checkable by the back end, but checkable via an explicit ;;; test in type check conversion (:HAIRY), or ;;; -- not reasonably checkable at all (:TOO-HAIRY). ;;; -;;; A type is checkable if it either represents a fixed number of -;;; values (as determined by VALUES-TYPES), or it is the assertion for -;;; an MV-BIND. A type is simply checkable if all the type assertions -;;; have a TYPE-CHECK-TEMPLATE. In this :SIMPLE case, the second value -;;; is a list of the type restrictions specified for the leading -;;; positional values. +;;; We may check only fixed number of values; in any case the number +;;; of generated values is trusted. If we know the number of produced +;;; values, all of them are checked; otherwise if we know the number +;;; of consumed -- only they are checked; otherwise the check is not +;;; performed. +;;; +;;; A type is simply checkable if all the type assertions have a +;;; TYPE-CHECK-TEMPLATE. In this :SIMPLE case, the second value is a +;;; list of the type restrictions specified for the leading positional +;;; values. ;;; -;;; We force a check to be hairy even when there are fixed values if -;;; we are in a context where we may be forced to use the unknown -;;; values convention anyway. This is because IR2tran can't generate -;;; type checks for unknown values continuations but people could -;;; still be depending on the check being done. We only care about -;;; EXIT and RETURN (not MV-COMBINATION) since these are the only -;;; contexts where the ultimate values receiver +;;; Old comment: +;;; +;;; We force a check to be hairy even when there are fixed values +;;; if we are in a context where we may be forced to use the +;;; unknown values convention anyway. This is because IR2tran can't +;;; generate type checks for unknown values lvars but people could +;;; still be depending on the check being done. We only care about +;;; EXIT and RETURN (not MV-COMBINATION) since these are the only +;;; contexts where the ultimate values receiver ;;; ;;; In the :HAIRY case, the second value is a list of triples of ;;; the form: @@ -212,271 +251,253 @@ ;;; ;;; If true, the NOT-P flag indicates a test that the corresponding ;;; value is *not* of the specified TYPE. ORIGINAL-TYPE is the type -;;; asserted on this value in the continuation, for use in error +;;; asserted on this value in the lvar, for use in error ;;; messages. When NOT-P is true, this will be different from TYPE. ;;; -;;; This allows us to take what has been proven about CONT's type into -;;; consideration. If it is cheaper to test for the difference between -;;; the derived type and the asserted type, then we check for the -;;; negation of this type instead. -(defun continuation-check-types (cont force-hairy) - (declare (type continuation cont)) - (let ((ctype (continuation-type-to-check cont)) - (atype (continuation-asserted-type cont)) - (dest (continuation-dest cont))) +;;; This allows us to take what has been proven about CAST's argument +;;; type into consideration. If it is cheaper to test for the +;;; difference between the derived type and the asserted type, then we +;;; check for the negation of this type instead. +(defun cast-check-types (cast force-hairy) + (declare (type cast cast)) + (let* ((ctype (coerce-to-values (cast-type-to-check cast))) + (atype (coerce-to-values (cast-asserted-type cast))) + (dtype (node-derived-type cast)) + (value (cast-value cast)) + (lvar (node-lvar cast)) + (dest (and lvar (lvar-dest lvar))) + (n-consumed (cond ((not lvar) + nil) + ((lvar-single-value-p lvar) + 1) + ((and (mv-combination-p dest) + (eq (mv-combination-kind dest) :local)) + (let ((fun-ref (lvar-use (mv-combination-fun dest)))) + (length (lambda-vars (ref-leaf fun-ref))))))) + (n-required (length (values-type-required dtype)))) (aver (not (eq ctype *wild-type*))) - (multiple-value-bind (ctypes count) (no-fun-values-types ctype) - (multiple-value-bind (atypes acount) (no-fun-values-types ctype) - (aver (eq count acount)) - (cond ((not (eq count :unknown)) - (if (or (exit-p dest) - (and (return-p dest) - (multiple-value-bind (ignore count) - (values-types (return-result-type dest)) - (declare (ignore ignore)) - (eq count :unknown)))) - (maybe-negate-check cont ctypes atypes t) - (maybe-negate-check cont ctypes atypes force-hairy))) - ((and (mv-combination-p dest) - (eq (basic-combination-kind dest) :local)) - (aver (values-type-p ctype)) - (maybe-negate-check cont - (args-type-optional ctype) - (args-type-optional atype) - force-hairy)) - (t - (values :too-hairy nil))))))) - -;;; Do we want to do a type check? -(defun worth-type-check-p (cont) - (let ((dest (continuation-dest cont))) - (not (or (values-subtypep (continuation-proven-type cont) - (continuation-type-to-check cont)) - (and (combination-p dest) - (let ((kind (combination-kind dest))) - (or (eq kind :full) - (and (fun-info-p kind) - (null (fun-info-templates kind)) - (not (fun-info-ir2-convert kind))))) - ;; The theory is that the type assertion is from a - ;; declaration in (or on) the callee, so the callee - ;; should be able to do the check. We want to let - ;; the callee do the check, because it is possible - ;; that by the time of call that declaration will be - ;; changed and we do not want to make people - ;; recompile all calls to a function when they were - ;; originally compiled with a bad declaration. (See - ;; also bug 35.) - (values-subtypep (continuation-externally-checkable-type cont) - (continuation-type-to-check cont))) - (and (mv-combination-p dest) ; bug 220 - (eq (mv-combination-kind dest) :full)))))) - -;;; Return true if CONT is a continuation whose type the back end is -;;; likely to want to check. Since we don't know what template the -;;; back end is going to choose to implement the continuation's DEST, -;;; we use a heuristic. We always return T unless: -;;; -- nobody uses the value, or -;;; -- safety is totally unimportant, or -;;; -- the continuation is an argument to an unknown function, or -;;; -- the continuation is an argument to a known function that has + (cond ((and (null (values-type-optional dtype)) + (not (values-type-rest dtype))) + ;; we [almost] know how many values are produced + (maybe-negate-check value + (values-type-out ctype n-required) + (values-type-out atype n-required) + ;; backend checks only consumed values + (not (eql n-required n-consumed)) + n-required)) + ((lvar-single-value-p lvar) + ;; exactly one value is consumed + (principal-lvar-single-valuify lvar) + (flet ((get-type (type) + (acond ((args-type-required type) + (car it)) + ((args-type-optional type) + (car it)) + (t (bug "type ~S is too hairy" type))))) + (multiple-value-bind (ctype atype) + (values (get-type ctype) (get-type atype)) + (maybe-negate-check value + (list ctype) (list atype) + force-hairy + n-required)))) + ((and (mv-combination-p dest) + (eq (mv-combination-kind dest) :local)) + ;; we know the number of consumed values + (maybe-negate-check value + (adjust-list (values-type-types ctype) + n-consumed + *universal-type*) + (adjust-list (values-type-types atype) + n-consumed + *universal-type*) + force-hairy + n-required)) + (t + (values :too-hairy nil))))) + +;;; Return T is the cast appears to be from the declaration of the callee, +;;; and should be checked externally -- that is, by the callee and not the caller. +(defun cast-externally-checkable-p (cast) + (declare (type cast cast)) + (let* ((lvar (node-lvar cast)) + (dest (and lvar (lvar-dest lvar)))) + (and (combination-p dest) + ;; The theory is that the type assertion is from a declaration on the + ;; callee, so the callee should be able to do the check. We want to + ;; let the callee do the check, because it is possible that by the + ;; time of call that declaration will be changed and we do not want + ;; to make people recompile all calls to a function when they were + ;; originally compiled with a bad declaration. + ;; + ;; ALMOST-IMMEDIATELY-USED-P ensures that we don't delegate casts + ;; that occur before nodes that can cause observable side effects -- + ;; most commonly other non-external casts: so the order in which + ;; possible type errors are signalled matches with the evaluation + ;; order. + ;; + ;; FIXME: We should let more cases be handled by the callee then we + ;; currently do, see: https://bugs.launchpad.net/sbcl/+bug/309104 + ;; This is not fixable quite here, though, because flow-analysis has + ;; deleted the LVAR of the cast by the time we get here, so there is + ;; no destination. Perhaps we should mark cases inserted by + ;; ASSERT-CALL-TYPE explicitly, and delete those whose destination is + ;; deemed unreachable? + (almost-immediately-used-p lvar cast) + (values (values-subtypep (lvar-externally-checkable-type lvar) + (cast-type-to-check cast)))))) + +;;; Return true if CAST's value is an lvar whose type the back end is +;;; likely to be able to check (see GENERATE-TYPE-CHECKS). Since we +;;; don't know what template the back end is going to choose to +;;; implement the continuation's DEST, we use a heuristic. +;;; +;;; We always return T unless nobody uses the value (the backend +;;; cannot check unused LVAR chains). +;;; +;;; The logic used to be more complex, but most of the cases that used +;;; to be checked here are now dealt with differently . FIXME: but +;;; here's one we used to do, don't anymore, but could still benefit +;;; from, if we reimplemented it (elsewhere): +;;; +;;; -- If the lvar is an argument to a known function that has ;;; no IR2-CONVERT method or :FAST-SAFE templates that are -;;; compatible with the call's type. +;;; compatible with the call's type: return NIL. ;;; -;;; We must only return NIL when it is *certain* that a check will not -;;; be done, since if we pass up this chance to do the check, it will -;;; be too late. The penalty for being too conservative is duplicated -;;; type checks. The penalty for erring by being too speculative is -;;; much nastier, e.g. falling through without ever being able to find -;;; an appropriate VOP. -(defun probable-type-check-p (cont) - (declare (type continuation cont)) - (let ((dest (continuation-dest cont))) - (cond ((or (not dest) - (policy dest (zerop safety))) - nil) - ((basic-combination-p dest) - (let ((kind (basic-combination-kind dest))) - (cond ((eq cont (basic-combination-fun dest)) t) - ((eq kind :local) t) - ((eq kind :full) - (and (combination-p dest) - (not (values-subtypep ; explicit THE - (continuation-externally-checkable-type cont) - (continuation-type-to-check cont))))) - - ((eq kind :error) nil) - ;; :ERROR means that we have an invalid syntax of - ;; the call and the callee will detect it before - ;; thinking about types. - - ((fun-info-ir2-convert kind) t) - (t - (dolist (template (fun-info-templates kind) nil) - (when (eq (template-ltn-policy template) :fast-safe) - (multiple-value-bind (val win) - (valid-fun-use dest (template-type template)) - (when (or val (not win)) (return t))))))))) - (t t)))) - -;;; Return a form that we can convert to do a hairy type check of the -;;; specified TYPES. TYPES is a list of the format returned by -;;; CONTINUATION-CHECK-TYPES in the :HAIRY case. In place of the -;;; actual value(s) we are to check, we use 'DUMMY. This constant -;;; reference is later replaced with the actual values continuation. +;;; The code used to look like something like this: +;;; ... +;;; (:known +;;; (let ((info (basic-combination-fun-info dest))) +;;; (if (fun-info-ir2-convert info) +;;; t +;;; (dolist (template (fun-info-templates info) nil) +;;; (when (eq (template-ltn-policy template) +;;; :fast-safe) +;;; (multiple-value-bind (val win) +;;; (valid-fun-use dest (template-type template)) +;;; (when (or val (not win)) (return t))))))))))))) +;;; +;;; ADP says: It is still interesting. When we have a :SAFE template +;;; and the type assertion is derived from the destination function +;;; type, the check is unneccessary. We cannot return NIL here (the +;;; whole function has changed its meaning, and here NIL *forces* +;;; hairy check), but the functionality is interesting. +(defun probable-type-check-p (cast) + (declare (type cast cast)) + (let* ((lvar (node-lvar cast)) + (dest (and lvar (lvar-dest lvar)))) + (cond ((not dest) nil) + (t t)))) + +;;; Return a lambda form that we can convert to do a hairy type check +;;; of the specified TYPES. TYPES is a list of the format returned by +;;; LVAR-CHECK-TYPES in the :HAIRY case. ;;; ;;; Note that we don't attempt to check for required values being ;;; unsupplied. Such checking is impossible to efficiently do at the ;;; source level because our fixed-values conventions are optimized ;;; for the common MV-BIND case. -;;; -;;; We can always use MULTIPLE-VALUE-BIND, since the macro is clever -;;; about binding a single variable. (defun make-type-check-form (types) (let ((temps (make-gensym-list (length types)))) - `(multiple-value-bind ,temps 'dummy + `(multiple-value-bind ,temps + 'dummy ,@(mapcar (lambda (temp type) - (let* ((spec - (let ((*unparse-fun-type-simplify* t)) - (type-specifier (second type)))) - (test (if (first type) `(not ,spec) spec))) - `(unless (typep ,temp ',test) - (%type-check-error - ,temp - ',(type-specifier (third type)))))) - temps - types) + (let* ((spec + (let ((*unparse-fun-type-simplify* t)) + (type-specifier (second type)))) + (test (if (first type) `(not ,spec) spec))) + `(unless (typep ,temp ',test) + (%type-check-error + ,temp + ',(type-specifier (third type)))))) + temps + types) (values ,@temps)))) -;;; Splice in explicit type check code immediately before the node -;;; which is CONT's DEST. This code receives the value(s) that were -;;; being passed to CONT, checks the type(s) of the value(s), then -;;; passes them on to CONT. -(defun convert-type-check (cont types) - (declare (type continuation cont) (type list types)) - (with-ir1-environment-from-node (continuation-dest cont) - - ;; Ensuring that CONT starts a block lets us freely manipulate its uses. - (ensure-block-start cont) - - ;; Make a new continuation and move CONT's uses to it. - (let* ((new-start (make-continuation)) - (dest (continuation-dest cont)) - (prev (node-prev dest))) - (continuation-starts-block new-start) - (substitute-continuation-uses new-start cont) - - ;; Setting TYPE-CHECK in CONT to :DELETED indicates that the - ;; check has been done. - (setf (continuation-%type-check cont) :deleted) - - ;; Make the DEST node start its block so that we can splice in - ;; the type check code. - (when (continuation-use prev) - (node-ends-block (continuation-use prev))) - - (let* ((prev-block (continuation-block prev)) - (new-block (continuation-block new-start)) - (dummy (make-continuation))) - - ;; Splice in the new block before DEST, giving the new block - ;; all of DEST's predecessors. - (dolist (block (block-pred prev-block)) - (change-block-successor block prev-block new-block)) - - ;; Convert the check form, using the new block start as START - ;; and a dummy continuation as CONT. - (ir1-convert new-start dummy (make-type-check-form types)) - - ;; TO DO: Why should this be true? -- WHN 19990601 - (aver (eq (continuation-block dummy) new-block)) - - ;; KLUDGE: Comments at the head of this function in CMU CL - ;; said that somewhere in here we - ;; Set the new block's start and end cleanups to the *start* - ;; cleanup of PREV's block. This overrides the incorrect - ;; default from WITH-IR1-ENVIRONMENT-FROM-NODE. - ;; Unfortunately I can't find any code which corresponds to this. - ;; Perhaps it was a stale comment? Or perhaps I just don't - ;; understand.. -- WHN 19990521 - - (let ((node (continuation-use dummy))) - (setf (block-last new-block) node) - ;; Change the use to a use of CONT. (We need to use the - ;; dummy continuation to get the control transfer right, - ;; because we want to go to PREV's block, not CONT's.) - (delete-continuation-use node) - (add-continuation-use node cont)) - ;; Link the new block to PREV's block. - (link-blocks new-block prev-block)) - - ;; MAKE-TYPE-CHECK-FORM generated a form which checked the type - ;; of 'DUMMY, not a real form. At this point we convert to the - ;; real form by finding 'DUMMY and overwriting it with the new - ;; continuation. (We can find 'DUMMY because no LET conversion - ;; has been done yet.) The [mv-]combination code from the - ;; mv-bind in the check form will be the use of the new check - ;; continuation. We substitute for the first argument of this - ;; node. - (let* ((node (continuation-use cont)) - (args (basic-combination-args node)) - (victim (first args))) - (aver (and (= (length args) 1) - (eq (constant-value - (ref-leaf - (continuation-use victim))) - 'dummy))) - (substitute-continuation new-start victim))) - - ;; Invoking local call analysis converts this call to a LET. - (locall-analyze-component *current-component*)) +;;; Splice in explicit type check code immediately before CAST. This +;;; code receives the value(s) that were being passed to CAST-VALUE, +;;; checks the type(s) of the value(s), then passes them further. +(defun convert-type-check (cast types) + (declare (type cast cast) (type list types)) + (let ((value (cast-value cast)) + (length (length types))) + (filter-lvar value (make-type-check-form types)) + (reoptimize-lvar (cast-value cast)) + (setf (cast-type-to-check cast) *wild-type*) + (setf (cast-%type-check cast) nil) + (let* ((atype (cast-asserted-type cast)) + (atype (cond ((not (values-type-p atype)) + atype) + ((= length 1) + (single-value-type atype)) + (t + (make-values-type + :required (values-type-out atype length))))) + (dtype (node-derived-type cast)) + (dtype (make-values-type + :required (values-type-out dtype length)))) + (setf (cast-asserted-type cast) atype) + (setf (node-derived-type cast) dtype))) (values)) -;;; Emit a type warning for NODE. If the value of NODE is being used -;;; for a variable binding, we figure out which one for source -;;; context. If the value is a constant, we print it specially. We -;;; ignore nodes whose type is NIL, since they are supposed to never -;;; return. -(defun emit-type-warning (node) - (declare (type node node)) - (let* ((*compiler-error-context* node) - (cont (node-cont node)) - (atype-spec (type-specifier (continuation-asserted-type cont))) - (dtype (node-derived-type node)) - (dest (continuation-dest cont)) - (what (when (and (combination-p dest) - (eq (combination-kind dest) :local)) - (let ((lambda (combination-lambda dest)) - (pos (position-or-lose cont (combination-args dest)))) - (format nil "~:[A possible~;The~] binding of ~S" - (and (continuation-use cont) - (eq (functional-kind lambda) :let)) - (leaf-source-name (elt (lambda-vars lambda) - pos))))))) - (cond ((eq dtype *empty-type*)) - ((and (ref-p node) (constant-p (ref-leaf node))) - (compiler-warn "~:[This~;~:*~A~] is not a ~<~%~9T~:;~S:~>~% ~S" - what atype-spec (constant-value (ref-leaf node)))) - (t - (compiler-warn - "~:[Result~;~:*~A~] is a ~S, ~<~%~9T~:;not a ~S.~>" - what (type-specifier dtype) atype-spec)))) +;;; Check all possible arguments of CAST and emit type warnings for +;;; those with type errors. If the value of USE is being used for a +;;; variable binding, we figure out which one for source context. If +;;; the value is a constant, we print it specially. +(defun cast-check-uses (cast) + (declare (type cast cast)) + (let* ((lvar (node-lvar cast)) + (dest (and lvar (lvar-dest lvar))) + (value (cast-value cast)) + (atype (cast-asserted-type cast)) + (condition 'type-warning) + (not-ok-uses '())) + (do-uses (use value) + (let ((dtype (node-derived-type use))) + (if (values-types-equal-or-intersect dtype atype) + (setf condition 'type-style-warning) + (push use not-ok-uses)))) + (dolist (use (nreverse not-ok-uses)) + (let* ((*compiler-error-context* use) + (dtype (node-derived-type use)) + (atype-spec (type-specifier atype)) + (what (when (and (combination-p dest) + (eq (combination-kind dest) :local)) + (let ((lambda (combination-lambda dest)) + (pos (position-or-lose + lvar (combination-args dest)))) + (format nil "~:[A possible~;The~] binding of ~S" + (and (lvar-has-single-use-p lvar) + (eq (functional-kind lambda) :let)) + (leaf-source-name (elt (lambda-vars lambda) + pos))))))) + (cond ((and (ref-p use) (constant-p (ref-leaf use))) + (warn condition + :format-control + "~:[This~;~:*~A~] is not a ~<~%~9T~:;~S:~>~% ~S" + :format-arguments + (list what atype-spec + (constant-value (ref-leaf use))))) + (t + (warn condition + :format-control + "~:[Result~;~:*~A~] is a ~S, ~<~%~9T~:;not a ~S.~>" + :format-arguments + (list what (type-specifier dtype) atype-spec))))))) (values)) ;;; Loop over all blocks in COMPONENT that have TYPE-CHECK set, -;;; looking for continuations with TYPE-CHECK T. We do two mostly -;;; unrelated things: detect compile-time type errors and determine if -;;; and how to do run-time type checks. +;;; looking for CASTs with TYPE-CHECK T. We do two mostly unrelated +;;; things: detect compile-time type errors and determine if and how +;;; to do run-time type checks. ;;; -;;; If there is a compile-time type error, then we mark the -;;; continuation and emit a warning if appropriate. This part loops -;;; over all the uses of the continuation, since after we convert the -;;; check, the :DELETED kind will inhibit warnings about the types of -;;; other uses. +;;; If there is a compile-time type error, then we mark the CAST and +;;; emit a warning if appropriate. This part loops over all the uses +;;; of the continuation, since after we convert the check, the +;;; :DELETED kind will inhibit warnings about the types of other uses. ;;; -;;; If a continuation is too complex to be checked by the back end, or -;;; is better checked with explicit code, then convert to an explicit +;;; If the cast is too complex to be checked by the back end, or is +;;; better checked with explicit code, then convert to an explicit ;;; test. Assertions that can checked by the back end are passed ;;; through. Assertions that can't be tested are flamed about and ;;; marked as not needing to be checked. @@ -494,40 +515,36 @@ ;;; which may lead to inappropriate template choices due to the ;;; modification of argument types. (defun generate-type-checks (component) - (collect ((conts)) + (collect ((casts)) (do-blocks (block component) (when (block-type-check block) - (do-nodes (node cont block) - (let ((type-check (continuation-type-check cont))) - (unless (member type-check '(nil :deleted)) - (let ((atype (continuation-asserted-type cont))) - (do-uses (use cont) - (unless (values-types-equal-or-intersect - (node-derived-type use) atype) - (unless (policy node (= inhibit-warnings 3)) - (emit-type-warning use)))))) - (when (eq type-check t) - (cond ((worth-type-check-p cont) - (conts (cons cont (not (probable-type-check-p cont))))) - ((probable-type-check-p cont) - (setf (continuation-%type-check cont) :deleted)) - (t - (setf (continuation-%type-check cont) :no-check)))))) - (setf (block-type-check block) nil))) - (dolist (cont (conts)) - (destructuring-bind (cont . force-hairy) cont + ;; CAST-EXTERNALLY-CHECKABLE-P wants the backward pass + (do-nodes-backwards (node nil block) + (when (and (cast-p node) + (cast-type-check node)) + (cast-check-uses node) + (cond ((cast-externally-checkable-p node) + (setf (cast-%type-check node) :external)) + (t + ;; it is possible that NODE was marked :EXTERNAL by + ;; the previous pass + (setf (cast-%type-check node) t) + (casts (cons node (not (probable-type-check-p node)))))))) + (setf (block-type-check block) nil))) + (dolist (cast (casts)) + (destructuring-bind (cast . force-hairy) cast (multiple-value-bind (check types) - (continuation-check-types cont force-hairy) + (cast-check-types cast force-hairy) (ecase check (:simple) (:hairy - (convert-type-check cont types)) + (convert-type-check cast types)) (:too-hairy - (let* ((context (continuation-dest cont)) - (*compiler-error-context* context)) - (when (policy context (>= safety inhibit-warnings)) - (compiler-note + (let ((*compiler-error-context* cast)) + (when (policy cast (>= safety inhibit-warnings)) + (compiler-notify "type assertion too complex to check:~% ~S." - (type-specifier (continuation-asserted-type cont))))) - (setf (continuation-%type-check cont) :deleted))))))) + (type-specifier (coerce-to-values (cast-asserted-type cast)))))) + (setf (cast-type-to-check cast) *wild-type*) + (setf (cast-%type-check cast) nil))))))) (values))