(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 (sb!xc:gensym "UNIVERSE"))
- (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)
- ))))
+ ;; the :end argument can be commented out when
+ ;; bootstrapping on a < 1.0.9 SBCL errors out with
+ ;; a full call to DATA-VECTOR-REF-WITH-OFFSET.
+ :end (conset-max conset)))))
(defun copy-conset (conset)
(let ((ret (%copy-conset conset)))
(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))))))
+ (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))))
+ conset)
(defun conset= (conset1 conset2)
(let* ((vector1 (conset-vector conset1))
;;; to over-approximate and then linear search through the potential hits.
;;; LVARs can only be found in EQL (not-p = NIL) constraints, while constant
;;; and lambda-vars can only be found in EQL constraints.
-
(defun find-constraint (kind x y not-p)
(declare (type lambda-var x) (type constraint-y y) (type boolean not-p))
(etypecase y
;;; Lambda-var -- lvar EQL constraints only serve one purpose: remember whether
;;; an lvar is (only) written to by a ref to that lambda-var, and aren't ever
;;; propagated.
-
+;;;
+;;; Finally, the lambda-var conset is only used to track the whole set of
+;;; constraints associated with a given lambda-var, and thus easily delete
+;;; such constraints from a conset.
(defun register-constraint (x con y)
(declare (type lambda-var x) (type constraint con) (type constraint-y y))
(conset-adjoin con (lambda-var-constraints x))
(when (lambda-var-p y)
(register-constraint y new x))
new)))
-
-;;; If REF is to a LAMBDA-VAR with CONSTRAINTs (i.e. we can do flow
-;;; analysis on it), then return the LAMBDA-VAR, otherwise NIL.
-#!-sb-fluid (declaim (inline ok-ref-lambda-var))
-(defun ok-ref-lambda-var (ref)
- (declare (type ref ref))
- (let ((leaf (ref-leaf ref)))
- (when (and (lambda-var-p leaf)
- (lambda-var-constraints leaf))
- leaf)))
-
-;;; See if LVAR's single USE is a REF to a LAMBDA-VAR and they are EQL
-;;; according to CONSTRAINTS. Return LAMBDA-VAR if so.
-(defun ok-lvar-lambda-var (lvar constraints)
- (declare (type lvar lvar))
- (let ((use (lvar-uses lvar)))
- (cond ((ref-p use)
- (let ((lambda-var (ok-ref-lambda-var use)))
- (when lambda-var
- (let ((constraint (find-constraint 'eql lambda-var lvar nil)))
- (when (and constraint (conset-member constraint constraints))
- lambda-var)))))
- ((cast-p use)
- (ok-lvar-lambda-var (cast-value use) constraints)))))
-
+\f
+;;; Actual conset interface
+;;;
+;;; Constraint propagation needs to iterate over the set of lambda-vars known to
+;;; be EQL to a given variable (including itself), via DO-EQL-VARS.
+;;;
+;;; It also has to iterate through constraints that are inherited by EQL variables
+;;; (DO-INHERITABLE-CONSTRAINTS), and through constraints used by
+;;; CONSTRAIN-REF-TYPE (to derive the type of a REF to a lambda-var).
+;;;
+;;; Consets must keep track of which lvars are EQL to a given lambda-var (result
+;;; from a REF to the lambda-var): CONSET-LVAR-LAMBDA-VAR-EQL-P and
+;;; CONSET-ADD-LVAR-LAMBDA-VAR-EQL. This, as all other constraints, must of
+;;; course be cleared when a lambda-var's constraints are dropped because of
+;;; assignment.
+;;;
+;;; Consets must be able to add constraints to a given lambda-var
+;;; (CONSET-ADD-CONSTRAINT), and to the set of variables EQL to a given
+;;; lambda-var (CONSET-ADD-CONSTRAINT-TO-EQL).
+;;;
+;;; When a lambda-var is assigned to, all the constraints involving that variable
+;;; must be dropped: constraint propagation is flow-sensitive, so the constraints
+;;; relate to the variable at a given range of program point. In such cases,
+;;; constraint propagation calls CONSET-CLEAR-LAMBDA-VAR.
+;;;
+;;; Finally, one of the main strengths of constraint propagation in SBCL is the
+;;; tracking of EQL variables to help constraint propagation. When two variables
+;;; are known to be EQL (e.g. after a branch), ADD-EQL-VAR-VAR-CONSTRAINT is
+;;; called to add the EQL constraint, but also have each equality class inherit
+;;; the other's (inheritable) constraints.
+;;;
+;;; On top of that, we have the usual bulk set operations: intersection, copy,
+;;; equality or emptiness testing. There's also union, but that's only an
+;;; optimisation to avoid useless copies in ADD-TEST-CONSTRAINTS and
+;;; FIND-BLOCK-TYPE-CONSTRAINTS.
(defmacro do-conset-constraints-intersection ((symbol (conset constraints) &optional result)
- &body body)
+ &body body)
(let ((min (gensym "MIN"))
(max (gensym "MAX")))
(once-only ((conset conset)
(when ,constraints
(let ((,min (conset-min ,conset))
(,max (conset-max ,conset)))
+ (declare (optimize speed))
(map nil (lambda (constraint)
(declare (type constraint constraint))
(let ((number (constraint-number constraint)))
(do-conset-constraints-intersection
(con (,conset (lambda-var-inheritable-constraints ,variable)) ,result)
(body-fun con))))))
+
+(declaim (inline conset-lvar-lambda-var-eql-p conset-add-lvar-lambda-var-eql))
+(defun conset-lvar-lambda-var-eql-p (conset lvar lambda-var)
+ (let ((constraint (find-constraint 'eql lambda-var lvar nil)))
+ (and constraint
+ (conset-member constraint conset))))
+
+(defun conset-add-lvar-lambda-var-eql (conset lvar lambda-var)
+ (let ((constraint (find-or-create-constraint 'eql lambda-var lvar nil)))
+ (conset-adjoin constraint conset)))
+
+(declaim (inline conset-add-constraint conset-add-constraint-to-eql))
+(defun conset-add-constraint (conset kind x y not-p)
+ (declare (type conset conset)
+ (type lambda-var x))
+ (conset-adjoin (find-or-create-constraint kind x y not-p)
+ conset))
+
+(defun conset-add-constraint-to-eql (conset kind x y not-p &optional (target conset))
+ (declare (type conset target conset)
+ (type lambda-var x))
+ (do-eql-vars (x (x conset))
+ (conset-add-constraint target kind x y not-p)))
+
+(declaim (inline conset-clear-lambda-var))
+(defun conset-clear-lambda-var (conset var)
+ (conset-difference conset (lambda-var-constraints var)))
+
+;;; 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-inheritable-constraints (con (constraints from-var))
+ (let ((eq-x (eq from-var (constraint-x con)))
+ (eq-y (eq from-var (constraint-y con))))
+ (dolist (var vars)
+ (conset-add-constraint target
+ (constraint-kind con)
+ (if eq-x var (constraint-x con))
+ (if eq-y var (constraint-y con))
+ (constraint-not-p con))))))
+
+;; 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 ((constraint (find-or-create-constraint 'eql var1 var2 nil)))
+ (unless (conset-member constraint target)
+ (conset-adjoin constraint target)
+ (collect ((eql1) (eql2))
+ (do-eql-vars (var1 (var1 constraints))
+ (eql1 var1))
+ (do-eql-vars (var2 (var2 constraints))
+ (eql2 var2))
+ (inherit-constraints (eql1) var2 constraints target)
+ (inherit-constraints (eql2) var1 constraints target))
+ t)))
+\f
+;;; If REF is to a LAMBDA-VAR with CONSTRAINTs (i.e. we can do flow
+;;; analysis on it), then return the LAMBDA-VAR, otherwise NIL.
+#!-sb-fluid (declaim (inline ok-ref-lambda-var))
+(defun ok-ref-lambda-var (ref)
+ (declare (type ref ref))
+ (let ((leaf (ref-leaf ref)))
+ (when (and (lambda-var-p leaf)
+ (lambda-var-constraints leaf))
+ leaf)))
+
+;;; See if LVAR's single USE is a REF to a LAMBDA-VAR and they are EQL
+;;; according to CONSTRAINTS. Return LAMBDA-VAR if so.
+(defun ok-lvar-lambda-var (lvar constraints)
+ (declare (type lvar lvar))
+ (let ((use (lvar-uses lvar)))
+ (cond ((ref-p use)
+ (let ((lambda-var (ok-ref-lambda-var use)))
+ (and lambda-var
+ (conset-lvar-lambda-var-eql-p constraints lvar lambda-var)
+ lambda-var)))
+ ((cast-p use)
+ (ok-lvar-lambda-var (cast-value use) constraints)))))
;;;; Searching constraints
-;;; Add the indicated test constraint to BLOCK. We don't add the
-;;; constraint if the block has multiple predecessors, since it only
-;;; holds on this particular path.
-(defun add-test-constraint (fun x y not-p constraints target)
- (cond ((and (eq 'eql fun) (lambda-var-p y) (not not-p))
- (add-eql-var-var-constraint x y constraints target))
- (t
- (do-eql-vars (x (x constraints))
- (let ((con (find-or-create-constraint fun x y not-p)))
- (conset-adjoin con target)))))
+;;; Add the indicated test constraint to TARGET.
+(defun precise-add-test-constraint (fun x y not-p constraints target)
+ (if (and (eq 'eql fun) (lambda-var-p y) (not not-p))
+ (add-eql-var-var-constraint x y constraints target)
+ (conset-add-constraint-to-eql constraints fun x y not-p target))
(values))
+(defun add-test-constraint (quick-p fun x y not-p constraints target)
+ (cond (quick-p
+ (conset-add-constraint target fun x y not-p))
+ (t
+ (precise-add-test-constraint fun x y not-p constraints target))))
;;; Add complementary constraints to the consequent and alternative
;;; blocks of IF. We do nothing if X is NIL.
-(defun add-complement-constraints (fun x y not-p constraints
- consequent-constraints
- alternative-constraints)
+(declaim (inline precise-add-test-constraint quick-add-complement-constraints))
+(defun precise-add-complement-constraints (fun x y not-p constraints
+ consequent-constraints
+ alternative-constraints)
(when x
- (add-test-constraint fun x y not-p constraints
- consequent-constraints)
- (add-test-constraint fun x y (not not-p) constraints
- alternative-constraints))
+ (precise-add-test-constraint fun x y not-p constraints
+ consequent-constraints)
+ (precise-add-test-constraint fun x y (not not-p) constraints
+ alternative-constraints))
(values))
+(defun quick-add-complement-constraints (fun x y not-p
+ consequent-constraints
+ alternative-constraints)
+ (when x
+ (conset-add-constraint consequent-constraints fun x y not-p)
+ (conset-add-constraint alternative-constraints fun x y (not not-p)))
+ (values))
+
+(defun add-complement-constraints (quick-p fun x y not-p constraints
+ consequent-constraints
+ alternative-constraints)
+ (if quick-p
+ (quick-add-complement-constraints fun x y not-p
+ consequent-constraints
+ alternative-constraints)
+ (precise-add-complement-constraints fun x y not-p constraints
+ consequent-constraints
+ alternative-constraints)))
+
+(defun add-combination-test-constraints (use constraints
+ consequent-constraints
+ alternative-constraints
+ quick-p)
+ (flet ((add (fun x y not-p)
+ (add-complement-constraints quick-p
+ fun x y not-p
+ constraints
+ consequent-constraints
+ alternative-constraints))
+ (prop (triples target)
+ (map nil (lambda (constraint)
+ (destructuring-bind (kind x y &optional not-p)
+ constraint
+ (when (and kind x y)
+ (add-test-constraint quick-p
+ kind x y
+ not-p constraints
+ target))))
+ triples)))
+ (when (eq (combination-kind use) :known)
+ (binding* ((info (combination-fun-info use) :exit-if-null)
+ (propagate (fun-info-constraint-propagate-if
+ info)
+ :exit-if-null))
+ (multiple-value-bind (lvar type if else)
+ (funcall propagate use constraints)
+ (prop if consequent-constraints)
+ (prop else alternative-constraints)
+ (when (and lvar type)
+ (add 'typep (ok-lvar-lambda-var lvar constraints)
+ type nil)
+ (return-from add-combination-test-constraints)))))
+ (let* ((name (lvar-fun-name
+ (basic-combination-fun use)))
+ (args (basic-combination-args use))
+ (ptype (gethash name *backend-predicate-types*)))
+ (when ptype
+ (add 'typep (ok-lvar-lambda-var (first args)
+ constraints)
+ ptype nil)))))
+
;;; Add test constraints to the consequent and alternative blocks of
;;; the test represented by USE.
(defun add-test-constraints (use if constraints)
;; need to avoid barfing on this case.
(unless (eq (if-consequent if) (if-alternative if))
(let ((consequent-constraints (make-conset))
- (alternative-constraints (make-conset)))
+ (alternative-constraints (make-conset))
+ (quick-p (policy if (> compilation-speed speed))))
(macrolet ((add (fun x y not-p)
- `(add-complement-constraints ,fun ,x ,y ,not-p
+ `(add-complement-constraints quick-p
+ ,fun ,x ,y ,not-p
constraints
consequent-constraints
alternative-constraints)))
(var2 (ok-lvar-lambda-var arg2 constraints)))
;; The code below assumes that the constant is the
;; second argument in case of variable to constant
- ;; comparision which is sometimes true (see source
+ ;; comparison which is sometimes true (see source
;; transformations for EQ, EQL and CHAR=). Fixing
;; that would result in more constant substitutions
;; which is not a universally good thing, thus the
;; unnatural asymmetry of the tests.
(cond ((not var1)
(when var2
- (add-test-constraint 'typep var2 (lvar-type arg1)
+ (add-test-constraint quick-p
+ 'typep var2 (lvar-type arg1)
nil constraints
consequent-constraints)))
(var2
(add 'eql var1 var2 nil))
((constant-lvar-p arg2)
(add 'eql var1
- (let ((use (principal-lvar-use arg2)))
- (if (ref-p use)
- (ref-leaf use)
- (find-constant (lvar-value arg2))))
+ (find-constant (lvar-value arg2))
nil))
(t
- (add-test-constraint 'typep var1 (lvar-type arg2)
+ (add-test-constraint quick-p
+ 'typep var1 (lvar-type arg2)
nil constraints
consequent-constraints)))))
((< >)
(when var2
(add (if (eq name '<) '> '<) var2 (lvar-type arg1) nil))))
(t
- (let ((ptype (gethash name *backend-predicate-types*)))
- (when ptype
- (add 'typep (ok-lvar-lambda-var (first args) constraints)
- ptype nil))))))))))
+ (add-combination-test-constraints use constraints
+ consequent-constraints
+ alternative-constraints
+ quick-p))))))))
(values consequent-constraints alternative-constraints))))
;;;; Applying constraints
(eq (numeric-type-complexp x) :real)))
;;; Exactly the same as CONSTRAIN-INTEGER-TYPE, but for float numbers.
+;;;
+;;; In contrast to the integer version, here the input types can have
+;;; open bounds in addition to closed ones and we don't increment or
+;;; decrement a bound to honor OR-EQUAL being NIL but put an open bound
+;;; into the result instead, if appropriate.
(defun constrain-float-type (x y greater or-equal)
(declare (type numeric-type x y))
(declare (ignorable x y greater or-equal)) ; for CROSS-FLOAT-INFINITY-KLUDGE
(tighter-p (x ref)
(cond ((null x) nil)
((null ref) t)
- ((and or-equal
- (= (type-bound-number x) (type-bound-number ref)))
- ;; X is tighter if REF is not an open bound and X is
- (and (not (consp ref)) (consp x)))
+ ((= (type-bound-number x) (type-bound-number ref))
+ ;; X is tighter if X is an open bound and REF is not
+ (and (consp x) (not (consp ref))))
(greater
(< (type-bound-number ref) (type-bound-number x)))
(t
(let ((lvar (ref-lvar ref))
(leaf (ref-leaf ref)))
(when (and (lambda-var-p leaf) lvar)
- (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-inheritable-constraints (con (constraints from-var))
- (let ((eq-x (eq from-var (constraint-x con)))
- (eq-y (eq from-var (constraint-y con))))
- (dolist (var vars)
- (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 (conset-adjoin con target)
- (collect ((eql1) (eql2))
- (do-eql-vars (var1 (var1 constraints))
- (eql1 var1))
- (do-eql-vars (var2 (var2 constraints))
- (eql2 var2))
- (inherit-constraints (eql1) var2 constraints target)
- (inherit-constraints (eql2) var1 constraints target))
- t)))
+ (conset-add-lvar-lambda-var-eql gen lvar leaf))))
;; Add an (EQL LAMBDA-VAR LAMBDA-VAR) constraint on VAR and LVAR's
;; LAMBDA-VAR if possible.
when (and val (lambda-var-constraints var))
do (let ((type (lvar-type val)))
(unless (eq type *universal-type*)
- (let ((con (find-or-create-constraint 'typep var type nil)))
- (conset-adjoin con gen))))
+ (conset-add-constraint gen 'typep var type nil)))
(maybe-add-eql-var-var-constraint var val gen)))))
(ref
(when (ok-ref-lambda-var node)
(when var
(let ((atype (single-value-type (cast-derived-type node)))) ;FIXME
(unless (eq atype *universal-type*)
- (do-eql-vars (var (var gen))
- (let ((con (find-or-create-constraint 'typep var atype nil)))
- (conset-adjoin con gen)))))))))
+ (conset-add-constraint-to-eql gen 'typep var atype nil)))))))
(cset
(binding* ((var (set-var node))
(nil (lambda-var-p var) :exit-if-null)
- (cons (lambda-var-constraints var) :exit-if-null))
- (conset-difference gen cons)
+ (nil (lambda-var-constraints var) :exit-if-null))
+ (when (policy node (and (= speed 3) (> speed compilation-speed)))
+ (let ((type (lambda-var-type var)))
+ (unless (eql *universal-type* type)
+ (do-eql-vars (other (var gen))
+ (unless (eql other var)
+ (conset-add-constraint gen 'typep other type nil))))))
+ (conset-clear-lambda-var gen var)
(let ((type (single-value-type (node-derived-type node))))
(unless (eq type *universal-type*)
- (let ((con (find-or-create-constraint 'typep var type nil)))
- (conset-adjoin con gen))))
- (maybe-add-eql-var-var-constraint var (set-value node) gen)))))
+ (conset-add-constraint gen 'typep var type nil)))
+ (unless (policy node (> compilation-speed speed))
+ (maybe-add-eql-var-var-constraint var (set-value node) gen))))
+ (combination
+ (when (eq (combination-kind node) :known)
+ (binding* ((info (combination-fun-info node) :exit-if-null)
+ (propagate (fun-info-constraint-propagate info)
+ :exit-if-null)
+ (constraints (funcall propagate node gen))
+ (register (if (policy node
+ (> compilation-speed speed))
+ #'conset-add-constraint
+ #'conset-add-constraint-to-eql)))
+ (map nil (lambda (constraint)
+ (destructuring-bind (kind x y &optional not-p)
+ constraint
+ (when (and kind x y)
+ (funcall register gen
+ kind x y
+ not-p))))
+ constraints))))))
gen)
(defun constraint-propagate-if (block gen)
(add-test-constraints use node gen))))))
;;; Starting from IN compute OUT and (consequent/alternative
-;;; constraints if the block ends with and IF). Return the list of
+;;; constraints if the block ends with an IF). Return the list of
;;; successors that may need to be recomputed.
(defun find-block-type-constraints (block final-pass-p)
(declare (type cblock block))