;;; breakdown of side effects, since we do very little code motion on
;;; IR1. We are interested in some deeper semantic properties such as
;;; whether it is safe to pass stack closures to.
+;;;
+;;; FIXME: This whole notion of "bad" explicit attributes is bad for
+;;; maintenance. How confident are we that we have no defknowns for functions
+;;; with functional arguments that are missing the CALL attribute? Much better
+;;; to have NO-CALLS, as it is much less likely to break accidentally.
(!def-boolean-attribute ir1
;; may call functions that are passed as arguments. In order to
;; determine what other effects are present, we must find the
;; effects of all arguments that may be functions.
call
- ;; may incorporate function or number arguments into the result or
- ;; somehow pass them upward. Note that this applies to any argument
- ;; that *might* be a function or number, not just the arguments that
- ;; always are.
- unsafe
;; may fail to return during correct execution. Errors are O.K.
+ ;; UNUSED, BEWARE OF BITROT.
unwind
;; the (default) worst case. Includes all the other bad things, plus
;; any other possible bad thing. If this is present, the above bad
;; attributes will be explicitly present as well.
any
+ ;; all arguments are safe for dynamic extent.
+ ;; (We used to have an UNSAFE attribute, which was basically the inverse
+ ;; of this, but it was unused and bitrotted, so when we started making
+ ;; use of the information we flipped the name and meaning the safe way
+ ;; around.)
+ dx-safe
;; may be constant-folded. The function has no side effects, but may
;; be affected by side effects on the arguments. e.g. SVREF, MAPC.
;; Functions that side-effect their arguments are not considered to
;; in the safe code. If a function MUST signal errors, then it is
;; not unsafely-flushable even if it is movable or foldable.
unsafely-flushable
+ ;; return value is important, and ignoring it is probably a mistake.
+ ;; Unlike the other attributes, this is used only for style
+ ;; warnings and has no effect on optimization.
+ important-result
;; may be moved with impunity. Has no side effects except possibly
;; consing, and is affected only by its arguments.
+ ;; UNUSED, BEWARE OF BITROT.
movable
;; The function is a true predicate likely to be open-coded. Convert
;; any non-conditional uses into (IF <pred> T NIL). Not usually
;; The function does explicit argument type checking, so the
;; declared type should not be asserted when a definition is
;; compiled.
- explicit-check)
+ explicit-check
+ ;; The function should always be translated by a VOP (i.e. it should
+ ;; should never be converted into a full call). This is used strictly
+ ;; as a consistency checking mechanism inside the compiler during IR2
+ ;; transformation.
+ always-translatable)
(defstruct (fun-info #-sb-xc-host (:pure t))
;; boolean attributes of this function.
;; further optimiz'ns) is backwards from the return convention for
;; transforms. -- WHN 19990917
(optimizer nil :type (or function null))
+ ;; a function computing the constant or literal arguments which are
+ ;; destructively modified by the call.
+ (destroyed-constant-args nil :type (or function null))
;; If true, a special-case LTN annotation method that is used in
;; place of the standard type/policy template selection. It may use
;; arbitrary code to choose a template, decide to do a full call, or
(ltn-annotate nil :type (or function null))
;; If true, the special-case IR2 conversion method for this
;; function. This deals with funny functions, and anything else that
- ;; can't be handled using the template mechanism. The Combination
+ ;; can't be handled using the template mechanism. The COMBINATION
;; node and the IR2-BLOCK are passed as arguments.
(ir2-convert nil :type (or function null))
+ ;; If true, the function can stack-allocate the result. The
+ ;; COMBINATION node is passed as an argument.
+ (stack-allocate-result nil :type (or function null))
+ ;; If true, the function can add flow-sensitive type information
+ ;; about the state of the world after its execution. The COMBINATION
+ ;; node is passed as an argument, along with the current set of
+ ;; active constraints for the block. The function returns a
+ ;; sequence of constraints; a constraint is a triplet of a
+ ;; constraint kind (a symbol, see (defstruct (constraint ...)) in
+ ;; constraint.lisp) and arguments, either LVARs, LAMBDA-VARs, or
+ ;; CTYPEs. If any of these arguments is NIL, the constraint is
+ ;; skipped. This simplifies integration with OK-LVAR-LAMBDA-VAR,
+ ;; which maps LVARs to LAMBDA-VARs. An optional fourth value in
+ ;; each constraint flips the meaning of the constraint if it is
+ ;; non-NIL.
+ (constraint-propagate nil :type (or function null))
+ ;; If true, the function can add flow-sensitive type information
+ ;; depending on the truthiness of its return value. Returns two
+ ;; values, a LVAR and a CTYPE. The LVAR is of that CTYPE iff the
+ ;; function returns true.
+ ;; It may also return additional third and fourth values. Each is
+ ;; a sequence of constraints (see CONSTRAINT-PROPAGATE), for the
+ ;; consequent and alternative branches, respectively.
+ (constraint-propagate-if nil :type (or function null))
;; all the templates that could be used to translate this function
;; into IR2, sorted by increasing cost.
(templates nil :type list)
;; If non-null, then this function is a unary type predicate for
;; this type.
- (predicate-type nil :type (or ctype null)))
+ (predicate-type nil :type (or ctype null))
+ ;; If non-null, the index of the argument which becomes the result
+ ;; of the function.
+ (result-arg nil :type (or index null)))
(defprinter (fun-info)
(attributes :test (not (zerop attributes))
;;; Grab the FUN-INFO and enter the function, replacing any old
;;; one with the same type and note.
(declaim (ftype (function (t list function &optional (or string null)
- (member t nil))
- *)
- %deftransform))
+ (member t nil))
+ *)
+ %deftransform))
(defun %deftransform (name type fun &optional note important)
(let* ((ctype (specifier-type type))
- (note (or note "optimize"))
- (info (fun-info-or-lose name))
- (old (find-if (lambda (x)
- (and (type= (transform-type x) ctype)
- (string-equal (transform-note x) note)
- (eq (transform-important x) important)))
- (fun-info-transforms info))))
+ (note (or note "optimize"))
+ (info (fun-info-or-lose name))
+ (old (find-if (lambda (x)
+ (and (type= (transform-type x) ctype)
+ (string-equal (transform-note x) note)
+ (eq (transform-important x) important)))
+ (fun-info-transforms info))))
(cond (old
- (style-warn "Overwriting ~S" old)
+ (style-warn 'sb!kernel:redefinition-with-deftransform
+ :transform old)
(setf (transform-function old) fun
(transform-note old) note))
(t
;;; Make a FUN-INFO structure with the specified type, attributes
;;; and optimizers.
(declaim (ftype (function (list list attributes &key
- (:derive-type (or function null))
- (:optimizer (or function null)))
- *)
- %defknown))
-(defun %defknown (names type attributes &key derive-type optimizer)
+ (:derive-type (or function null))
+ (:optimizer (or function null))
+ (:destroyed-constant-args (or function null))
+ (:result-arg (or index null))
+ (:overwrite-fndb-silently boolean))
+ *)
+ %defknown))
+(defun %defknown (names type attributes
+ &key derive-type optimizer destroyed-constant-args result-arg
+ overwrite-fndb-silently)
(let ((ctype (specifier-type type))
- (info (make-fun-info :attributes attributes
+ (info (make-fun-info :attributes attributes
:derive-type derive-type
- :optimizer optimizer))
- (target-env *info-environment*))
+ :optimizer optimizer
+ :destroyed-constant-args destroyed-constant-args
+ :result-arg result-arg)))
(dolist (name names)
- (let ((old-fun-info (info :function :info name)))
- (when old-fun-info
- ;; This is handled as an error because it's generally a bad
- ;; thing to blow away all the old optimization stuff. It's
- ;; also a potential source of sneaky bugs:
- ;; DEFKNOWN FOO
- ;; DEFTRANSFORM FOO
- ;; DEFKNOWN FOO ; possibly hidden inside some macroexpansion
- ;; ; Now the DEFTRANSFORM doesn't exist in the target Lisp.
- ;; However, it's continuable because it might be useful to do
- ;; it when testing new optimization stuff interactively.
- (cerror "Go ahead, overwrite it."
- "~@<overwriting old FUN-INFO ~2I~_~S ~I~_for ~S~:>"
- old-fun-info name)))
- (setf (info :function :type name target-env) ctype)
- (setf (info :function :where-from name target-env) :declared)
- (setf (info :function :kind name target-env) :function)
- (setf (info :function :info name target-env) info)))
+ (unless overwrite-fndb-silently
+ (let ((old-fun-info (info :function :info name)))
+ (when old-fun-info
+ ;; This is handled as an error because it's generally a bad
+ ;; thing to blow away all the old optimization stuff. It's
+ ;; also a potential source of sneaky bugs:
+ ;; DEFKNOWN FOO
+ ;; DEFTRANSFORM FOO
+ ;; DEFKNOWN FOO ; possibly hidden inside some macroexpansion
+ ;; ; Now the DEFTRANSFORM doesn't exist in the target Lisp.
+ ;; However, it's continuable because it might be useful to do
+ ;; it when testing new optimization stuff interactively.
+ (cerror "Go ahead, overwrite it."
+ "~@<overwriting old FUN-INFO ~2I~_~S ~I~_for ~S~:>"
+ old-fun-info name))))
+ (setf (info :function :type name) ctype)
+ (setf (info :function :where-from name) :declared)
+ (setf (info :function :kind name) :function)
+ (setf (info :function :info name) info)))
names)
;;; Return the FUN-INFO for NAME or die trying. Since this is
(declaim (ftype (sfunction (t) fun-info) fun-info-or-lose))
(defun fun-info-or-lose (name)
(let (;; FIXME: Do we need this rebinding here? It's a literal
- ;; translation of the old CMU CL rebinding to
- ;; (OR *BACKEND-INFO-ENVIRONMENT* *INFO-ENVIRONMENT*),
- ;; and it's not obvious whether the rebinding to itself is
- ;; needed that SBCL doesn't need *BACKEND-INFO-ENVIRONMENT*.
- (*info-environment* *info-environment*))
+ ;; translation of the old CMU CL rebinding to
+ ;; (OR *BACKEND-INFO-ENVIRONMENT* *INFO-ENVIRONMENT*),
+ ;; and it's not obvious whether the rebinding to itself is
+ ;; needed that SBCL doesn't need *BACKEND-INFO-ENVIRONMENT*.
+ (*info-environment* *info-environment*))
(let ((old (info :function :info name)))
(unless old (error "~S is not a known function." name))
(setf (info :function :info name) (copy-fun-info old)))))
;;; only be done when the result value is that argument.
(defun result-type-first-arg (call)
(declare (type combination call))
- (let ((cont (first (combination-args call))))
- (when cont (continuation-type cont))))
+ (let ((lvar (first (combination-args call))))
+ (when lvar (lvar-type lvar))))
(defun result-type-last-arg (call)
(declare (type combination call))
- (let ((cont (car (last (combination-args call)))))
- (when cont (continuation-type cont))))
+ (let ((lvar (car (last (combination-args call)))))
+ (when lvar (lvar-type lvar))))
;;; Derive the result type according to the float contagion rules, but
;;; always return a float. This is used for irrational functions that
(defun result-type-float-contagion (call)
(declare (type combination call))
(reduce #'numeric-contagion (combination-args call)
- :key #'continuation-type
- :initial-value (specifier-type 'single-float)))
+ :key #'lvar-type
+ :initial-value (specifier-type 'single-float)))
;;; Return a closure usable as a derive-type method for accessing the
;;; N'th argument. If arg is a list, result is a list. If arg is a
(defun sequence-result-nth-arg (n)
(lambda (call)
(declare (type combination call))
- (let ((cont (nth (1- n) (combination-args call))))
- (when cont
- (let ((type (continuation-type cont)))
- (if (array-type-p type)
- (specifier-type
- `(vector ,(type-specifier (array-type-element-type type))))
- (let ((ltype (specifier-type 'list)))
- (when (csubtypep type ltype)
- ltype))))))))
+ (let ((lvar (nth (1- n) (combination-args call))))
+ (when lvar
+ (let ((type (lvar-type lvar)))
+ (if (array-type-p type)
+ (specifier-type
+ `(vector ,(type-specifier (array-type-element-type type))))
+ (let ((ltype (specifier-type 'list)))
+ (when (csubtypep type ltype)
+ ltype))))))))
;;; Derive the type to be the type specifier which is the Nth arg.
(defun result-type-specifier-nth-arg (n)
(lambda (call)
(declare (type combination call))
- (let ((cont (nth (1- n) (combination-args call))))
- (when (and cont (constant-continuation-p cont))
- (careful-specifier-type (continuation-value cont))))))
+ (let ((lvar (nth (1- n) (combination-args call))))
+ (when (and lvar (constant-lvar-p lvar))
+ (careful-specifier-type (lvar-value lvar))))))
;;; Derive the type to be the type specifier which is the Nth arg,
;;; with the additional restriptions noted in the CLHS for STRING and
(defun creation-result-type-specifier-nth-arg (n)
(lambda (call)
(declare (type combination call))
- (let ((cont (nth (1- n) (combination-args call))))
- (when (and cont (constant-continuation-p cont))
- (let* ((specifier (continuation-value cont))
- (lspecifier (if (atom specifier) (list specifier) specifier)))
- (cond
- ((eq (car lspecifier) 'string)
- (destructuring-bind (string &rest size)
- lspecifier
- (declare (ignore string))
- (careful-specifier-type
- `(vector character ,@(when size size)))))
- ((eq (car lspecifier) 'simple-string)
- (destructuring-bind (simple-string &rest size)
- lspecifier
- (declare (ignore simple-string))
- (careful-specifier-type
- `(simple-array character ,@(if size (list size) '((*)))))))
- (t
- (let ((ctype (careful-specifier-type specifier)))
- (if (and (array-type-p ctype)
- (eq (array-type-specialized-element-type ctype)
- *wild-type*))
- ;; I don't think I'm allowed to modify what I get
- ;; back from SPECIFIER-TYPE; it is, after all,
- ;; cached. Better copy it, then.
- (let ((real-ctype (copy-structure ctype)))
- (setf (array-type-element-type real-ctype)
- *universal-type*
- (array-type-specialized-element-type real-ctype)
- *universal-type*)
- real-ctype)
- ctype)))))))))
+ (let ((lvar (nth (1- n) (combination-args call))))
+ (when (and lvar (constant-lvar-p lvar))
+ (let* ((specifier (lvar-value lvar))
+ (lspecifier (if (atom specifier) (list specifier) specifier)))
+ (cond
+ ((eq (car lspecifier) 'string)
+ (destructuring-bind (string &rest size)
+ lspecifier
+ (declare (ignore string))
+ (careful-specifier-type
+ `(vector character ,@(when size size)))))
+ ((eq (car lspecifier) 'simple-string)
+ (destructuring-bind (simple-string &rest size)
+ lspecifier
+ (declare (ignore simple-string))
+ (careful-specifier-type
+ `(simple-array character ,@(if size (list size) '((*)))))))
+ (t
+ (let ((ctype (careful-specifier-type specifier)))
+ (if (and (array-type-p ctype)
+ (eq (array-type-specialized-element-type ctype)
+ *wild-type*))
+ ;; I don't think I'm allowed to modify what I get
+ ;; back from SPECIFIER-TYPE; it is, after all,
+ ;; cached. Better copy it, then.
+ (let ((real-ctype (copy-structure ctype)))
+ (setf (array-type-element-type real-ctype)
+ *universal-type*
+ (array-type-specialized-element-type real-ctype)
+ *universal-type*)
+ real-ctype)
+ ctype)))))))))
+
+(defun remove-non-constants-and-nils (fun)
+ (lambda (list)
+ (remove-if-not #'lvar-value
+ (remove-if-not #'constant-lvar-p (funcall fun list)))))
+
+;;; FIXME: bad name (first because it uses 1-based indexing; second
+;;; because it doesn't get the nth constant arguments)
+(defun nth-constant-args (&rest indices)
+ (lambda (list)
+ (let (result)
+ (do ((i 1 (1+ i))
+ (list list (cdr list))
+ (indices indices))
+ ((null indices) (nreverse result))
+ (when (= i (car indices))
+ (when (constant-lvar-p (car list))
+ (push (car list) result))
+ (setf indices (cdr indices)))))))
+
+;;; FIXME: a number of the sequence functions not only do not destroy
+;;; their argument if it is empty, but also leave it alone if :start
+;;; and :end bound a null sequence, or if :count is 0. This test is a
+;;; bit complicated to implement, verging on the impossible, but for
+;;; extra points (fill #\1 "abc" :start 0 :end 0) should not cause a
+;;; warning.
+(defun nth-constant-nonempty-sequence-args (&rest indices)
+ (lambda (list)
+ (let (result)
+ (do ((i 1 (1+ i))
+ (list list (cdr list))
+ (indices indices))
+ ((null indices) (nreverse result))
+ (when (= i (car indices))
+ (when (constant-lvar-p (car list))
+ (let ((value (lvar-value (car list))))
+ (unless (or (typep value 'null)
+ (typep value '(vector * 0)))
+ (push (car list) result))))
+ (setf indices (cdr indices)))))))
(/show0 "knownfun.lisp end of file")
projects / sbcl.git / blobdiff