(in-package "SB!C")
+;;; *CONSTRAINT-UNIVERSE* gets bound in IR1-PHASES to a fresh,
+;;; zero-length, non-zero-total-size vector-with-fill-pointer.
+(declaim (type (and vector (not simple-vector)) *constraint-universe*))
+(defvar *constraint-universe*)
+
(deftype constraint-y () '(or ctype lvar lambda-var constant))
(defstruct (constraint
;; If true, negates the sense of the constraint, so the relation
;; does *not* hold.
(not-p nil :type boolean))
-
-(defvar *constraint-number*)
-(declaim (type (integer 0) *constraint-number*))
-
+\f
+;;; Historically, CMUCL and SBCL have used a sparse set implementation
+;;; for which most operations are O(n) (see sset.lisp), but at the
+;;; cost of at least a full word of pointer for each constraint set
+;;; element. Using bit-vectors instead of pointer structures saves a
+;;; lot of space and thus GC time (particularly on 64-bit machines),
+;;; and saves time on copy, union, intersection, and difference
+;;; operations; but makes iteration slower. Circa September 2008,
+;;; switching to bit-vectors gave a modest (5-10%) improvement in real
+;;; compile time for most Lisp systems, and as much as 20-30% for some
+;;; particularly CP-dependent systems.
+
+;;; It's bad to leave commented code in files, but if some clever
+;;; person comes along and makes SSETs better than bit-vectors as sets
+;;; for constraint propagation, or if bit-vectors on some XC host
+;;; really lose compared to SSETs, here's the conset API as a wrapper
+;;; around SSETs:
+#+nil
+(progn
+ (deftype conset () 'sset)
+ (declaim (ftype (sfunction (conset) boolean) conset-empty))
+ (declaim (ftype (sfunction (conset) conset) copy-conset))
+ (declaim (ftype (sfunction (constraint conset) boolean) conset-member))
+ (declaim (ftype (sfunction (constraint conset) boolean) conset-adjoin))
+ (declaim (ftype (sfunction (conset conset) boolean) conset=))
+ (declaim (ftype (sfunction (conset conset) (values)) conset-union))
+ (declaim (ftype (sfunction (conset conset) (values)) conset-intersection))
+ (declaim (ftype (sfunction (conset conset) (values)) conset-difference))
+ (defun make-conset () (make-sset))
+ (defmacro do-conset-elements ((constraint conset &optional result) &body body)
+ `(do-sset-elements (,constraint ,conset ,result) ,@body))
+ (defmacro do-conset-intersection
+ ((constraint conset1 conset2 &optional result) &body body)
+ `(do-conset-elements (,constraint ,conset1 ,result)
+ (when (conset-member ,constraint ,conset2)
+ ,@body)))
+ (defun conset-empty (conset) (sset-empty conset))
+ (defun copy-conset (conset) (copy-sset conset))
+ (defun conset-member (constraint conset) (sset-member constraint conset))
+ (defun conset-adjoin (constraint conset) (sset-adjoin constraint conset))
+ (defun conset= (conset1 conset2) (sset= conset1 conset2))
+ ;; Note: CP doesn't ever care whether union, intersection, and
+ ;; difference change the first set. (This is an important degree of
+ ;; freedom, since some ways of implementing sets lose a great deal
+ ;; when these operations are required to track changes.)
+ (defun conset-union (conset1 conset2)
+ (sset-union conset1 conset2) (values))
+ (defun conset-intersection (conset1 conset2)
+ (sset-intersection conset1 conset2) (values))
+ (defun conset-difference (conset1 conset2)
+ (sset-difference conset1 conset2) (values)))
+
+(locally
+ ;; This is performance critical for the compiler, and benefits
+ ;; from the following declarations. Probably you'll want to
+ ;; disable these declarations when debugging consets.
+ (declare #-sb-xc-host (optimize (speed 3) (safety 0) (space 0)))
+ (declaim (inline %constraint-number))
+ (defun %constraint-number (constraint)
+ (sset-element-number constraint))
+ (defstruct (conset
+ (:constructor make-conset ())
+ (:copier %copy-conset))
+ (vector (make-array
+ ;; FIXME: make POWER-OF-TWO-CEILING available earlier?
+ (ash 1 (integer-length (1- (length *constraint-universe*))))
+ :element-type 'bit :initial-element 0)
+ :type simple-bit-vector)
+ ;; Bit-vectors win over lightweight hashes for copy, union,
+ ;; intersection, difference, but lose for iteration if you iterate
+ ;; over the whole vector. Tracking extrema helps a bit.
+ (min 0 :type fixnum)
+ (max 0 :type fixnum))
+
+ (defmacro do-conset-elements ((constraint conset &optional result) &body body)
+ (with-unique-names (vector index start end
+ #-sb-xc-host ignore
+ #-sb-xc-host constraint-universe-end)
+ (let* ((constraint-universe #+sb-xc-host '*constraint-universe*
+ #-sb-xc-host (gensym))
+ (with-array-data
+ #+sb-xc-host '(progn)
+ #-sb-xc-host `(with-array-data
+ ((,constraint-universe *constraint-universe*)
+ (,ignore 0) (,constraint-universe-end nil)
+ :check-fill-pointer t)
+ (declare (ignore ,ignore))
+ (aver (<= ,end ,constraint-universe-end)))))
+ `(let* ((,vector (conset-vector ,conset))
+ (,start (conset-min ,conset))
+ (,end (min (conset-max ,conset) (length ,vector))))
+ (,@with-array-data
+ (do ((,index ,start (1+ ,index))) ((>= ,index ,end) ,result)
+ (when (plusp (sbit ,vector ,index))
+ (let ((,constraint (elt ,constraint-universe ,index)))
+ ,@body))))))))
+
+ ;; Oddly, iterating just between the maximum of the two sets' minima
+ ;; and the minimum of the sets' maxima slowed down CP.
+ (defmacro do-conset-intersection
+ ((constraint conset1 conset2 &optional result) &body body)
+ `(do-conset-elements (,constraint ,conset1 ,result)
+ (when (conset-member ,constraint ,conset2)
+ ,@body)))
+
+ (defun conset-empty (conset)
+ (or (= (conset-min conset) (conset-max conset))
+ ;; TODO: I bet FIND on bit-vectors can be optimized, if it
+ ;; isn't.
+ (not (find 1 (conset-vector conset)
+ :start (conset-min conset)
+ ;; By inspection, supplying :END here breaks the
+ ;; build with a "full call to
+ ;; DATA-VECTOR-REF-WITH-OFFSET" in the
+ ;; cross-compiler. If that should change, add
+ ;; :end (conset-max conset)
+ ))))
+
+ (defun copy-conset (conset)
+ (let ((ret (%copy-conset conset)))
+ (setf (conset-vector ret) (copy-seq (conset-vector conset)))
+ ret))
+
+ (defun %conset-grow (conset new-size)
+ (declare (type index new-size))
+ (setf (conset-vector conset)
+ (replace (the simple-bit-vector
+ (make-array
+ (ash 1 (integer-length (1- new-size)))
+ :element-type 'bit
+ :initial-element 0))
+ (the simple-bit-vector
+ (conset-vector conset)))))
+
+ (declaim (inline conset-grow))
+ (defun conset-grow (conset new-size)
+ (declare (type index new-size))
+ (when (< (length (conset-vector conset)) new-size)
+ (%conset-grow conset new-size))
+ (values))
+
+ (defun conset-member (constraint conset)
+ (let ((number (%constraint-number constraint))
+ (vector (conset-vector conset)))
+ (when (< number (length vector))
+ (plusp (sbit vector number)))))
+
+ (defun conset-adjoin (constraint conset)
+ (prog1
+ (not (conset-member constraint conset))
+ (let ((number (%constraint-number constraint)))
+ (conset-grow conset (1+ number))
+ (setf (sbit (conset-vector conset) number) 1)
+ (setf (conset-min conset) (min number (conset-min conset)))
+ (when (>= number (conset-max conset))
+ (setf (conset-max conset) (1+ number))))))
+
+ (defun conset= (conset1 conset2)
+ (let* ((vector1 (conset-vector conset1))
+ (vector2 (conset-vector conset2))
+ (length1 (length vector1))
+ (length2 (length vector2)))
+ (if (= length1 length2)
+ ;; When the lengths are the same, we can rely on EQUAL being
+ ;; nicely optimized on bit-vectors.
+ (equal vector1 vector2)
+ (multiple-value-bind (shorter longer)
+ (if (< length1 length2)
+ (values vector1 vector2)
+ (values vector2 vector1))
+ ;; FIXME: make MISMATCH fast on bit-vectors.
+ (dotimes (index (length shorter))
+ (when (/= (sbit vector1 index) (sbit vector2 index))
+ (return-from conset= nil)))
+ (if (find 1 longer :start (length shorter))
+ nil
+ t)))))
+
+ (macrolet
+ ((defconsetop (name bit-op)
+ `(defun ,name (conset-1 conset-2)
+ (declare (optimize (speed 3) (safety 0)))
+ (let* ((size-1 (length (conset-vector conset-1)))
+ (size-2 (length (conset-vector conset-2)))
+ (new-size (max size-1 size-2)))
+ (conset-grow conset-1 new-size)
+ (conset-grow conset-2 new-size))
+ (let ((vector1 (conset-vector conset-1))
+ (vector2 (conset-vector conset-2)))
+ (declare (simple-bit-vector vector1 vector2))
+ (setf (conset-vector conset-1) (,bit-op vector1 vector2 t))
+ ;; Update the extrema.
+ ,(ecase name
+ ((conset-union)
+ `(setf (conset-min conset-1)
+ (min (conset-min conset-1)
+ (conset-min conset-2))
+ (conset-max conset-1)
+ (max (conset-max conset-1)
+ (conset-max conset-2))))
+ ((conset-intersection)
+ `(let ((start (max (conset-min conset-1)
+ (conset-min conset-2)))
+ (end (min (conset-max conset-1)
+ (conset-max conset-2))))
+ (setf (conset-min conset-1)
+ (if (> start end)
+ 0
+ (or (position 1 (conset-vector conset-1)
+ :start start :end end)
+ 0))
+ (conset-max conset-1)
+ (if (> start end)
+ 0
+ (let ((position
+ (position
+ 1 (conset-vector conset-1)
+ :start start :end end :from-end t)))
+ (if position
+ (1+ position)
+ 0))))))
+ ((conset-difference)
+ `(setf (conset-min conset-1)
+ (or (position 1 (conset-vector conset-1)
+ :start (conset-min conset-1)
+ :end (conset-max conset-1))
+ 0)
+ (conset-max conset-1)
+ (let ((position
+ (position
+ 1 (conset-vector conset-1)
+ :start (conset-min conset-1)
+ :end (conset-max conset-1)
+ :from-end t)))
+ (if position
+ (1+ position)
+ 0))))))
+ (values))))
+ (defconsetop conset-union bit-ior)
+ (defconsetop conset-intersection bit-and)
+ (defconsetop conset-difference bit-andc2)))
+\f
(defun find-constraint (kind x y not-p)
(declare (type lambda-var x) (type constraint-y y) (type boolean not-p))
(etypecase y
(ctype
- (do-sset-elements (con (lambda-var-constraints x) nil)
+ (do-conset-elements (con (lambda-var-constraints x) nil)
(when (and (eq (constraint-kind con) kind)
(eq (constraint-not-p con) not-p)
(type= (constraint-y con) y))
(return con))))
((or lvar constant)
- (do-sset-elements (con (lambda-var-constraints x) nil)
+ (do-conset-elements (con (lambda-var-constraints x) nil)
(when (and (eq (constraint-kind con) kind)
(eq (constraint-not-p con) not-p)
(eq (constraint-y con) y))
(return con))))
(lambda-var
- (do-sset-elements (con (lambda-var-constraints x) nil)
+ (do-conset-elements (con (lambda-var-constraints x) nil)
(when (and (eq (constraint-kind con) kind)
(eq (constraint-not-p con) not-p)
(let ((cx (constraint-x con)))
(defun find-or-create-constraint (kind x y not-p)
(declare (type lambda-var x) (type constraint-y y) (type boolean not-p))
(or (find-constraint kind x y not-p)
- (let ((new (make-constraint (incf *constraint-number*) kind x y not-p)))
- (sset-adjoin new (lambda-var-constraints x))
+ (let ((new (make-constraint (length *constraint-universe*)
+ kind x y not-p)))
+ (vector-push-extend new *constraint-universe*
+ (1+ (length *constraint-universe*)))
+ (conset-adjoin new (lambda-var-constraints x))
(when (lambda-var-p y)
- (sset-adjoin new (lambda-var-constraints y)))
+ (conset-adjoin new (lambda-var-constraints y)))
new)))
;;; If REF is to a LAMBDA-VAR with CONSTRAINTs (i.e. we can do flow
(let ((lambda-var (ok-ref-lambda-var use)))
(when lambda-var
(let ((constraint (find-constraint 'eql lambda-var lvar nil)))
- (when (and constraint (sset-member constraint constraints))
+ (when (and constraint (conset-member constraint constraints))
lambda-var)))))
((cast-p use)
(ok-lvar-lambda-var (cast-value use) constraints)))))
(flet ((body-fun ()
,@body))
(body-fun)
- (do-sset-elements (con ,constraints ,result)
+ (do-conset-elements (con ,constraints ,result)
(let ((other (and (eq (constraint-kind con) 'eql)
(eq (constraint-not-p con) nil)
(cond ((eq ,var (constraint-x con))
(t
(do-eql-vars (x (x constraints))
(let ((con (find-or-create-constraint fun x y not-p)))
- (sset-adjoin con target)))))
+ (conset-adjoin con target)))))
(values))
;;; Add complementary constraints to the consequent and alternative
;; can't guarantee that the optimization will be done, so we still
;; need to avoid barfing on this case.
(unless (eq (if-consequent if) (if-alternative if))
- (let ((consequent-constraints (make-sset))
- (alternative-constraints (make-sset)))
+ (let ((consequent-constraints (make-conset))
+ (alternative-constraints (make-conset)))
(macrolet ((add (fun x y not-p)
`(add-complement-constraints ,fun ,x ,y ,not-p
- constraints
- consequent-constraints
- alternative-constraints)))
+ constraints
+ consequent-constraints
+ alternative-constraints)))
(typecase use
(ref
(add 'typep (ok-lvar-lambda-var (ref-lvar use) constraints)
;;; restrictions from flow analysis IN, set the type for REF
;;; accordingly.
(defun constrain-ref-type (ref constraints in)
- (declare (type ref ref) (type sset constraints in))
+ (declare (type ref ref) (type conset constraints in))
;; KLUDGE: The NOT-SET and NOT-FPZ here are so that we don't need to
;; cons up endless union types when propagating large number of EQL
;; constraints -- eg. from large CASE forms -- instead we just
(push x not-fpz)
(when (or constrain-symbols (null x) (not (symbolp x)))
(add-to-xset x not-set)))))
- (do-sset-elements (con constraints)
- (when (sset-member con in)
- (let* ((x (constraint-x con))
- (y (constraint-y con))
- (not-p (constraint-not-p con))
- (other (if (eq x leaf) y x))
- (kind (constraint-kind con)))
- (case kind
- (typep
- (if not-p
- (if (member-type-p other)
- (mapc-member-type-members #'note-not other)
- (setq not-res (type-union not-res other)))
- (setq res (type-approx-intersection2 res other))))
- (eql
- (unless (lvar-p other)
- (let ((other-type (leaf-type other)))
- (if not-p
- (when (and (constant-p other)
- (member-type-p other-type))
- (note-not (constant-value other)))
- (let ((leaf-type (leaf-type leaf)))
- (cond
- ((or (constant-p other)
- (and (leaf-refs other) ; protect from
+ ;; KLUDGE: the implementations of DO-CONSET-INTERSECTION will
+ ;; probably run faster when the smaller set comes first, so
+ ;; don't change the order here.
+ (do-conset-intersection (con constraints in)
+ (let* ((x (constraint-x con))
+ (y (constraint-y con))
+ (not-p (constraint-not-p con))
+ (other (if (eq x leaf) y x))
+ (kind (constraint-kind con)))
+ (case kind
+ (typep
+ (if not-p
+ (if (member-type-p other)
+ (mapc-member-type-members #'note-not other)
+ (setq not-res (type-union not-res other)))
+ (setq res (type-approx-intersection2 res other))))
+ (eql
+ (unless (lvar-p other)
+ (let ((other-type (leaf-type other)))
+ (if not-p
+ (when (and (constant-p other)
+ (member-type-p other-type))
+ (note-not (constant-value other)))
+ (let ((leaf-type (leaf-type leaf)))
+ (cond
+ ((or (constant-p other)
+ (and (leaf-refs other) ; protect from
; deleted vars
- (csubtypep other-type leaf-type)
- (not (type= other-type leaf-type))))
- (change-ref-leaf ref other)
- (when (constant-p other) (return)))
- (t
- (setq res (type-approx-intersection2
- res other-type)))))))))
- ((< >)
- (cond
- ((and (integer-type-p res) (integer-type-p y))
- (let ((greater (eq kind '>)))
- (let ((greater (if not-p (not greater) greater)))
- (setq res
- (constrain-integer-type res y greater not-p)))))
- ((and (float-type-p res) (float-type-p y))
- (let ((greater (eq kind '>)))
- (let ((greater (if not-p (not greater) greater)))
- (setq res
- (constrain-float-type res y greater not-p))))))))))))
+ (csubtypep other-type leaf-type)
+ (not (type= other-type leaf-type))))
+ (change-ref-leaf ref other)
+ (when (constant-p other) (return)))
+ (t
+ (setq res (type-approx-intersection2
+ res other-type)))))))))
+ ((< >)
+ (cond
+ ((and (integer-type-p res) (integer-type-p y))
+ (let ((greater (eq kind '>)))
+ (let ((greater (if not-p (not greater) greater)))
+ (setq res
+ (constrain-integer-type res y greater not-p)))))
+ ((and (float-type-p res) (float-type-p y))
+ (let ((greater (eq kind '>)))
+ (let ((greater (if not-p (not greater) greater)))
+ (setq res
+ (constrain-float-type res y greater not-p)))))))))))
(cond ((and (if-p (node-dest ref))
(or (xset-member-p nil not-set)
(csubtypep (specifier-type 'null) not-res)))
(let ((lvar (ref-lvar ref))
(leaf (ref-leaf ref)))
(when (and (lambda-var-p leaf) lvar)
- (sset-adjoin (find-or-create-constraint 'eql leaf lvar nil)
- gen))))
+ (conset-adjoin (find-or-create-constraint 'eql leaf lvar nil)
+ gen))))
;;; Copy all CONSTRAINTS involving FROM-VAR - except the (EQL VAR
;;; LVAR) ones - to all of the variables in the VARS list.
(defun inherit-constraints (vars from-var constraints target)
- (do-sset-elements (con constraints)
+ (do-conset-elements (con constraints)
;; Constant substitution is controversial.
(unless (constant-p (constraint-y con))
(dolist (var vars)
(eq-y (eq from-var (constraint-y con))))
(when (or (and eq-x (not (lvar-p (constraint-y con))))
eq-y)
- (sset-adjoin (find-or-create-constraint
- (constraint-kind con)
- (if eq-x var (constraint-x con))
- (if eq-y var (constraint-y con))
- (constraint-not-p con))
- target)))))))
+ (conset-adjoin (find-or-create-constraint
+ (constraint-kind con)
+ (if eq-x var (constraint-x con))
+ (if eq-y var (constraint-y con))
+ (constraint-not-p con))
+ target)))))))
;; Add an (EQL LAMBDA-VAR LAMBDA-VAR) constraint on VAR1 and VAR2 and
;; inherit each other's constraints.
(defun add-eql-var-var-constraint (var1 var2 constraints
&optional (target constraints))
(let ((con (find-or-create-constraint 'eql var1 var2 nil)))
- (when (sset-adjoin con target)
+ (when (conset-adjoin con target)
(collect ((eql1) (eql2))
(do-eql-vars (var1 (var1 constraints))
(eql1 var1))
;;; constraint.]
;;; -- For any LAMBDA-VAR set, delete all constraints on that var; add
;;; a type constraint based on the new value type.
-(declaim (ftype (function (cblock sset boolean)
- sset)
+(declaim (ftype (function (cblock conset boolean)
+ conset)
constraint-propagate-in-block))
(defun constraint-propagate-in-block (block gen preprocess-refs-p)
(do-nodes (node lvar block)
do (let* ((type (lvar-type val))
(con (find-or-create-constraint 'typep var type
nil)))
- (sset-adjoin con gen))
+ (conset-adjoin con gen))
(maybe-add-eql-var-var-constraint var val gen)))))
(ref
(when (ok-ref-lambda-var node)
(let ((atype (single-value-type (cast-derived-type node)))) ;FIXME
(do-eql-vars (var (var gen))
(let ((con (find-or-create-constraint 'typep var atype nil)))
- (sset-adjoin con gen))))))))
+ (conset-adjoin con gen))))))))
(cset
(binding* ((var (set-var node))
(nil (lambda-var-p var) :exit-if-null)
(cons (lambda-var-constraints var) :exit-if-null))
- (sset-difference gen cons)
+ (conset-difference gen cons)
(let* ((type (single-value-type (node-derived-type node)))
(con (find-or-create-constraint 'typep var type nil)))
- (sset-adjoin con gen))
+ (conset-adjoin con gen))
(maybe-add-eql-var-var-constraint var (set-value node) gen)))))
gen)
block
(if final-pass-p
(block-in block)
- (copy-sset (block-in block)))
+ (copy-conset (block-in block)))
final-pass-p)))
(setf (block-gen block) gen)
(multiple-value-bind (consequent-constraints alternative-constraints)
(old-alternative-constraints (if-alternative-constraints node))
(succ ()))
;; Add the consequent and alternative constraints to GEN.
- (cond ((sset-empty consequent-constraints)
+ (cond ((conset-empty consequent-constraints)
(setf (if-consequent-constraints node) gen)
(setf (if-alternative-constraints node) gen))
(t
- (setf (if-consequent-constraints node) (copy-sset gen))
- (sset-union (if-consequent-constraints node)
- consequent-constraints)
+ (setf (if-consequent-constraints node) (copy-conset gen))
+ (conset-union (if-consequent-constraints node)
+ consequent-constraints)
(setf (if-alternative-constraints node) gen)
- (sset-union (if-alternative-constraints node)
- alternative-constraints)))
+ (conset-union (if-alternative-constraints node)
+ alternative-constraints)))
;; Has the consequent been changed?
(unless (and old-consequent-constraints
- (sset= (if-consequent-constraints node)
- old-consequent-constraints))
+ (conset= (if-consequent-constraints node)
+ old-consequent-constraints))
(push (if-consequent node) succ))
;; Has the alternative been changed?
(unless (and old-alternative-constraints
- (sset= (if-alternative-constraints node)
- old-alternative-constraints))
+ (conset= (if-alternative-constraints node)
+ old-alternative-constraints))
(push (if-alternative node) succ))
succ)
;; There is no IF.
(unless (and (block-out block)
- (sset= gen (block-out block)))
+ (conset= gen (block-out block)))
(setf (block-out block) gen)
(block-succ block))))))
(unless (lambda-var-constraints var)
(when (or (null (lambda-var-sets var))
(not (closure-var-p var)))
- (setf (lambda-var-constraints var) (make-sset)))))))
+ (setf (lambda-var-constraints var) (make-conset)))))))
(frob fun)
(dolist (let (lambda-lets fun))
(frob let)))))
;;; Return the constraints that flow from PRED to SUCC. This is
-;;; BLOCK-OUT unless PRED ends with and IF and test constraints were
+;;; BLOCK-OUT unless PRED ends with an IF and test constraints were
;;; added.
(defun block-out-for-successor (pred succ)
(declare (type cblock pred succ))
(let ((out (block-out-for-successor pred block)))
(when out
(if in
- (sset-intersection in out)
- (setq in (copy-sset out))))))
- (or in (make-sset))))
+ (conset-intersection in out)
+ (setq in (copy-conset out))))))
+ (or in (make-conset))))
(defun update-block-in (block)
(let ((in (compute-block-in block)))
- (cond ((and (block-in block) (sset= in (block-in block)))
+ (cond ((and (block-in block) (conset= in (block-in block)))
nil)
(t
(setf (block-in block) in)))))
(init-var-constraints component)
(unless (block-out (component-head component))
- (setf (block-out (component-head component)) (make-sset)))
+ (setf (block-out (component-head component)) (make-conset)))
(dolist (block (find-and-propagate-constraints component))
(unless (block-delete-p block)
projects / sbcl.git / blobdiff