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chez-openbsd/ta6ob/s/cpcommonize.ss

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2022-08-09 23:28:25 +02:00
;;; cpcommonize.ss
;;; Copyright 1984-2017 Cisco Systems, Inc.
;;;
;;; Licensed under the Apache License, Version 2.0 (the "License");
;;; you may not use this file except in compliance with the License.
;;; You may obtain a copy of the License at
;;;
;;; http://www.apache.org/licenses/LICENSE-2.0
;;;
;;; Unless required by applicable law or agreed to in writing, software
;;; distributed under the License is distributed on an "AS IS" BASIS,
;;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
;;; See the License for the specific language governing permissions and
;;; limitations under the License.
(begin
(define-who commonization-level
($make-thread-parameter
0
(lambda (x)
(unless (and (fixnum? x) (<= 0 x 9))
($oops who "invalid level ~s" x))
x)))
(define $cpcommonize
(let ()
(import (nanopass))
(include "base-lang.ss")
(define-record-type binding
(nongenerative)
(sealed #t)
(fields x (mutable e) size helper-box (mutable helper-b) (mutable helper-arg*))
(protocol
(lambda (new)
(lambda (x e size helper-box)
(new x e size helper-box #f #f)))))
(define-language Lcommonize1 (extends Lsrc)
(terminals
(+ (fixnum (size))))
(Expr (e body rtd-expr)
(- (letrec ([x* e*] ...) body))
(+ (letrec ([x* e* size] ...) body))))
(define-language Lcommonize2 (extends Lcommonize1)
(terminals
(- (fixnum (size)))
(+ (binding (b helper-b))))
(Expr (e body rtd-expr)
(- (letrec ([x* e* size] ...) body))
(+ (letrec (helper-b* ...) (b* ...) body))))
(define-syntax iffalse
(syntax-rules ()
[(_ e1 e2) e1 #;(or e1 (begin e2 #f))]))
(define-syntax iftrue
(syntax-rules ()
[(_ e1 e2) e1 #;(let ([t e1]) (and t (begin e2 t)))]))
(define Lcommonize1-lambda?
(lambda (e)
(nanopass-case (Lcommonize1 Expr) e
[(case-lambda ,preinfo ,cl* ...) #t]
[else #f])))
(define-pass cpcommonize0 : Lsrc (ir) -> Lcommonize1 ()
(Expr : Expr (ir) -> Expr (1)
[(set! ,maybe-src ,x ,[e size])
(values `(set! ,maybe-src ,x ,e) (fx+ 1 size))]
[(seq ,[e1 size1] ,[e2 size2])
(values `(seq ,e1 ,e2) (fx+ size1 size2))]
[(if ,[e1 size1] ,[e2 size2] ,[e3 size3])
(values `(if ,e1 ,e2 ,e3) (fx+ size1 size2 size3))]
[(foreign (,conv* ...) ,name ,[e size] (,arg-type* ...) ,result-type)
(values `(foreign (,conv* ...) ,name ,e (,arg-type* ...) ,result-type) (fx+ 1 size))]
[(fcallable (,conv* ...) ,[e size] (,arg-type* ...) ,result-type)
(values `(fcallable (,conv* ...) ,e (,arg-type* ...) ,result-type) (fx+ 1 size))]
; ($top-level-value 'x) adds just 1 to the size
[(call ,preinfo ,pr (quote ,d))
(guard (eq? (primref-name pr) '$top-level-value))
(values `(call ,preinfo ,pr (quote ,d)) 1)]
; (let ([x* e*] ...) body) splits into letrec binding unassigned variables to lambdas plus a let for the remaining bindings
[(call ,preinfo1 (case-lambda ,preinfo2 (clause (,x* ...) ,interface ,[body size])) ,[e* -> e* size*] ...)
(guard (fx= (length e*) interface))
(define-record-type fudge (nongenerative) (sealed #t) (fields x e size))
(let-values ([(lb* ob*) (partition
(lambda (b)
(and (not (prelex-assigned (fudge-x b)))
(Lcommonize1-lambda? (fudge-e b))))
(map make-fudge x* e* size*))])
(values
(let ([body (if (null? ob*)
body
`(call ,preinfo1
(case-lambda ,preinfo2
(clause (,(map fudge-x ob*) ...) ,(length ob*) ,body))
,(map fudge-e ob*) ...))])
(if (null? lb*)
body
`(letrec ([,(map fudge-x lb*) ,(map fudge-e lb*) ,(map fudge-size lb*)] ...) ,body)))
(apply fx+ size size*)))]
[(call ,preinfo ,[e size] ,[e* size*] ...)
(values `(call ,preinfo ,e ,e* ...) (apply fx+ size size*))]
[(case-lambda ,preinfo (clause (,x** ...) ,interface* ,[body* size*]) ...)
(values `(case-lambda ,preinfo (clause (,x** ...) ,interface* ,body*) ...) (apply fx+ 1 size*))]
[(letrec ([,x* ,[e* size*]] ...) ,[body size])
(values `(letrec ([,x* ,e* ,size*] ...) ,body) (apply fx+ size size*))]
[(record-ref ,rtd ,type ,index ,[e size])
(values `(record-ref ,rtd ,type ,index ,e) (fx+ size 1))]
[(record-set! ,rtd ,type ,index ,[e1 size1] ,[e2 size2])
(values `(record-set! ,rtd ,type ,index ,e1 ,e2) (fx+ size1 size2 1))]
[(record ,rtd ,[rtd-expr size] ,[e* size*] ...)
(values `(record ,rtd ,rtd-expr ,e* ...) (apply fx+ size size*))]
[(cte-optimization-loc ,box ,[e size])
(values `(cte-optimization-loc ,box ,e) size)]
[(immutable-list (,[e* size*] ...) ,[e size])
(values `(immutable-list (,e* ...) ,e) (apply fx+ size size*))]
[(quote ,d) (values `(quote ,d) 1)]
[(ref ,maybe-src ,x) (values `(ref ,maybe-src ,x) 1)]
[,pr (values pr 1)]
[(moi) (values `(moi) 1)]
[(pariah) (values `(pariah) 0)]
[(profile ,src) (values `(profile ,src) 0)]
[else (sorry! who "unhandled record ~s" ir)])
(let-values ([(e size) (Expr ir)]) e))
(define-pass cpcommonize1 : Lcommonize1 (ir worthwhile-size) -> Lcommonize2 ()
(definitions
(define worthwhile-size?
(lambda (expr-size)
(fx>= expr-size worthwhile-size)))
(define worthwhile-ratio?
(lambda (expr-size subst-count)
(or (fx= subst-count 0)
(fx>= (div expr-size subst-count) 4))))
(define-record-type subst
(nongenerative)
(sealed #t)
(fields t e1 e2))
(define-record-type frob
(nongenerative)
(sealed #t)
(fields subst* e b))
(define ht (make-hashtable values fx=))
(define make-sym
(lambda x*
(string->symbol (apply string-append (map (lambda (x) (if (prelex? x) (symbol->string (prelex-name x)) x)) x*)))))
(define same-preinfo?
(lambda (p1 p2)
; ignore differences in src and sexpr
#t))
(define same-preinfo-lambda?
(lambda (p1 p2)
; ignore differences src, sexpr, and name
(eq? (preinfo-lambda-libspec p1) (preinfo-lambda-libspec p2))))
(define-who same-type?
(lambda (ty1 ty2)
(nanopass-case (Ltype Type) ty1
[(fp-integer ,bits1)
(nanopass-case (Ltype Type) ty2
[(fp-integer ,bits2) (= bits1 bits2)]
[else #f])]
[(fp-unsigned ,bits1)
(nanopass-case (Ltype Type) ty2
[(fp-unsigned ,bits2) (= bits1 bits2)]
[else #f])]
[(fp-void)
(nanopass-case (Ltype Type) ty2
[(fp-void) #t]
[else #f])]
[(fp-scheme-object)
(nanopass-case (Ltype Type) ty2
[(fp-scheme-object) #t]
[else #f])]
[(fp-u8*)
(nanopass-case (Ltype Type) ty2
[(fp-u8*) #t]
[else #f])]
[(fp-u16*)
(nanopass-case (Ltype Type) ty2
[(fp-u16*) #t]
[else #f])]
[(fp-u32*)
(nanopass-case (Ltype Type) ty2
[(fp-u32*) #t]
[else #f])]
[(fp-fixnum)
(nanopass-case (Ltype Type) ty2
[(fp-fixnum) #t]
[else #f])]
[(fp-double-float)
(nanopass-case (Ltype Type) ty2
[(fp-double-float) #t]
[else #f])]
[(fp-single-float)
(nanopass-case (Ltype Type) ty2
[(fp-single-float) #t]
[else #f])]
[(fp-ftd ,ftd1)
(nanopass-case (Ltype Type) ty2
[(fp-ftd ,ftd2) (eq? ftd1 ftd2)]
[else #f])]
[else (sorry! who "unhandled foreign type ~s" ty1)])))
(define okay-to-subst?
(lambda (e)
(define free?
(lambda (x)
(and (not (prelex-operand x)) #t)))
(nanopass-case (Lcommonize1 Expr) e
[(ref ,maybe-src1 ,x1) (and (not (prelex-assigned x1)) (free? x1))]
[(quote ,d) #t]
[,pr (all-set? (prim-mask proc) (primref-flags pr))]
[else #f])))
(define constant-equal?
(lambda (x y)
(define record-equal?
(lambda (x y e?)
(let ([rtd ($record-type-descriptor x)])
(and (eq? ($record-type-descriptor y) rtd)
(let f ([field-name* (csv7:record-type-field-names rtd)] [i 0])
(or (null? field-name*)
(and (let ([accessor (csv7:record-field-accessor rtd i)])
(e? (accessor x) (accessor y)))
(f (cdr field-name*) (fx+ i 1)))))))))
(parameterize ([default-record-equal-procedure record-equal?])
; equal? should be okay since even mutable constants aren't supposed to be mutated
(equal? x y))))
(define same?
(lambda (e1 e2)
(nanopass-case (Lcommonize1 Expr) e1
[(ref ,maybe-src1 ,x1)
(nanopass-case (Lcommonize1 Expr) e2
[(ref ,maybe-src2 ,x2)
(or (eq? x1 x2)
(eq? (prelex-operand x1) x2))]
[else #f])]
[(quote ,d1)
(nanopass-case (Lcommonize1 Expr) e2
[(quote ,d2) (constant-equal? d1 d2)]
[else #f])]
[,pr1
(nanopass-case (Lcommonize1 Expr) e2
[,pr2 (eq? pr1 pr2)]
[else #f])]
[(moi)
(nanopass-case (Lcommonize1 Expr) e2
[(moi) #t]
[else #f])]
[(pariah)
(nanopass-case (Lcommonize1 Expr) e2
[(pariah) #t]
[else #f])]
[(profile ,src1)
(nanopass-case (Lcommonize1 Expr) e2
[(profile ,src2) (eq? src1 src2)]
[else #f])]
[(call ,preinfo1 ,pr1 (quote ,d1))
(guard (eq? (primref-name pr1) '$top-level-value))
(nanopass-case (Lcommonize1 Expr) e2
[(call ,preinfo2 ,pr2 (quote ,d2))
(guard (eq? (primref-name pr2) '$top-level-value))
(and (same-preinfo? preinfo1 preinfo2) (eq? d1 d2))]
[else #f])]
[else #f])))
(define-who unify
(lambda (e1 e2)
(module (with-env)
(define $with-env
(lambda (x1* x2* th)
(dynamic-wind
(lambda () (map (lambda (x1 x2) (prelex-operand-set! x1 x2) (prelex-operand-set! x2 #t)) x1* x2*))
th
(lambda () (map (lambda (x1 x2) (prelex-operand-set! x1 #f) (prelex-operand-set! x2 #f)) x1* x2*)))))
(define-syntax with-env
(syntax-rules ()
[(_ x1* x2* e) ($with-env x1* x2* (lambda () e))])))
(call/cc
(lambda (return)
(let ([subst* '()])
(define lookup-subst
(lambda (e1 e2)
(define same-subst?
(lambda (x)
(and (same? (subst-e1 x) e1) (same? (subst-e2 x) e2))))
(cond
[(find same-subst? subst*) =>
(lambda (subst)
(let ([t (subst-t subst)])
(set-prelex-multiply-referenced! t #t)
t))]
[else #f])))
(let ([e (with-output-language (Lcommonize1 Expr)
(let ()
(define fclause
(lambda (cl1 cl2)
(nanopass-case (Lcommonize1 CaseLambdaClause) cl1
[(clause (,x1* ...) ,interface1 ,body1)
(nanopass-case (Lcommonize1 CaseLambdaClause) cl2
[(clause (,x2* ...) ,interface2 ,body2)
(if (fx= interface1 interface2)
(with-env x1* x2*
(with-output-language (Lcommonize1 CaseLambdaClause)
`(clause (,x1* ...) ,interface1 ,(f body1 body2))))
(return (iffalse #f (printf "lambda interfaces don't match\n")) '()))])])))
(define f
(case-lambda
[(e1 e2) (f e1 e2 #f)]
[(e1 e2 call-position?)
(or (cond
[(same? e1 e2) e1]
[(and (not call-position?) (okay-to-subst? e1) (okay-to-subst? e2))
`(ref #f ,(or (lookup-subst e1 e2)
(let ([t (make-prelex*)])
(set-prelex-referenced! t #t)
(set! subst* (cons (make-subst t e1 e2) subst*))
t)))]
[else
(nanopass-case (Lcommonize1 Expr) e1
[(ref ,maybe-src1 ,x1) #f]
[(quote ,d) #f]
[,pr #f]
[(moi) #f]
[(profile ,src1) #f]
; reject non-same top-level-value calls with constant symbol so they
; don't end up being abstracted over the symbol in the residual code
[(call ,preinfo ,pr (quote ,d))
(guard (eq? (primref-name pr) '$top-level-value))
#f]
; don't allow abstraction of first (type) argument to $object-ref, foreign-ref, etc.,
; since they can't be inlined without a constant type.
; ditto for $tc-field's first (field) argument.
; there are many other primitives we don't catch here for which the compiler generates
; more efficient code when certain arguments are constant.
[(call ,preinfo1 ,pr1 (quote ,d1) ,e1* ...)
(guard (memq (primref-name pr1) '($object-ref $swap-object-ref $object-set foreign-ref foreign-set! $tc-field)))
(nanopass-case (Lcommonize1 Expr) e2
[(call ,preinfo2 ,pr2 (quote ,d2) ,e2* ...)
(guard (eq? pr2 pr1) (eq? d1 d2))
(and (same-preinfo? preinfo1 preinfo2)
(fx= (length e1*) (length e2*))
`(call ,preinfo1 ,pr1 (quote ,d1) ,(map f e1* e2*) ...))]
[else #f])]
[(call ,preinfo1 ,e1 ,e1* ...)
(nanopass-case (Lcommonize1 Expr) e2
[(call ,preinfo2 ,e2 ,e2* ...)
(and (fx= (length e1*) (length e2*))
(same-preinfo? preinfo1 preinfo2)
`(call ,preinfo1 ,(f e1 e2 #t) ,(map f e1* e2*) ...))]
[else #f])]
[(if ,e10 ,e11 ,e12)
(nanopass-case (Lcommonize1 Expr) e2
[(if ,e20 ,e21 ,e22)
`(if ,(f e10 e20) ,(f e11 e21) ,(f e12 e22))]
[else #f])]
[(case-lambda ,preinfo1 ,cl1* ...)
(nanopass-case (Lcommonize1 Expr) e2
[(case-lambda ,preinfo2 ,cl2* ...)
(and (fx= (length cl1*) (length cl2*))
(same-preinfo-lambda? preinfo1 preinfo2)
`(case-lambda ,preinfo1 ,(map fclause cl1* cl2*) ...))]
[else #f])]
[(seq ,e11 ,e12)
(nanopass-case (Lcommonize1 Expr) e2
[(seq ,e21 ,e22) `(seq ,(f e11 e21) ,(f e12 e22))]
[else #f])]
[(set! ,maybe-src1 ,x1 ,e1)
(nanopass-case (Lcommonize1 Expr) e2
[(set! ,maybe-src2 ,x2 ,e2)
(and (eq? x1 x2)
`(set! ,maybe-src1 ,x1 ,(f e1 e2)))]
[else #f])]
[(letrec ([,x1* ,e1* ,size1*] ...) ,body1)
(nanopass-case (Lcommonize1 Expr) e2
[(letrec ([,x2* ,e2* ,size2*] ...) ,body2)
(and (fx= (length x2*) (length x1*))
(andmap fx= size1* size2*)
(with-env x1* x2*
`(letrec ([,x1* ,(map f e1* e2*) ,size1*] ...) ,(f body1 body2))))]
[else #f])]
[(foreign (,conv1* ...) ,name1 ,e1 (,arg-type1* ...) ,result-type1)
(nanopass-case (Lcommonize1 Expr) e2
[(foreign (,conv2* ...) ,name2 ,e2 (,arg-type2* ...) ,result-type2)
(and (equal? conv1* conv2*)
(equal? name1 name2)
(fx= (length arg-type1*) (length arg-type2*))
(andmap same-type? arg-type1* arg-type2*)
(same-type? result-type1 result-type2)
`(foreign (,conv1* ...) ,name1 ,(f e1 e2) (,arg-type1* ...) ,result-type1))]
[else #f])]
[(fcallable (,conv1* ...) ,e1 (,arg-type1* ...) ,result-type1)
(nanopass-case (Lcommonize1 Expr) e2
[(fcallable (,conv2* ...) ,e2 (,arg-type2* ...) ,result-type2)
(and (equal? conv1* conv2*)
(fx= (length arg-type1*) (length arg-type2*))
(andmap same-type? arg-type1* arg-type2*)
(same-type? result-type1 result-type2)
`(fcallable (,conv1* ...) ,(f e1 e2) (,arg-type1* ...) ,result-type1))]
[else #f])]
[(cte-optimization-loc ,box1 ,e1)
(nanopass-case (Lcommonize1 Expr) e2
[(cte-optimization-loc ,box2 ,e2)
(and (eq? box1 box2)
`(cte-optimization-loc ,box1 ,(f e1 e2)))]
[else #f])]
[else (sorry! who "unhandled record ~s" e1)])])
(return (iffalse #f (parameterize ([print-level 3] [print-length 5]) (printf "unify failed for ~s and ~s (call-position ~s)\n" e1 e2 call-position?))) '()))]))
(f e1 e2)))])
(values e subst*)))))))
(define sort-substs
; reestablish original argument order for substituted variables where possible
; so the arguments to an abstracted procedure aren't shuffled around in the
; call to the generated helper.
(lambda (subst0* x1* x2*)
(define (this? x x*) (and (not (null? x*)) (eq? x (car x*))))
(define (next x*) (if (null? x*) x* (cdr x*)))
(let-values ([(new-subst* subst*) (let f ([x1* x1*] [x2* x2*] [subst* subst0*] [n (length subst0*)])
(cond
[(fx= n 0) (values '() subst*)]
[(find (lambda (subst)
(define (is-this-arg? e x*)
(nanopass-case (Lcommonize1 Expr) e
[(ref ,maybe-src ,x) (this? x x*)]
[else #f]))
(or (is-this-arg? (subst-e1 subst) x1*)
(is-this-arg? (subst-e2 subst) x2*)))
subst*) =>
(lambda (subst)
(let-values ([(new-subst* subst*) (f (next x1*) (next x2*) (remq subst subst*) (fx- n 1))])
(values (cons subst new-subst*) subst*)))]
[else
(let-values ([(new-subst* subst*) (f (next x1*) (next x2*) subst* (fx- n 1))])
(values (cons (car subst*) new-subst*) (cdr subst*)))]))])
(safe-assert (null? subst*))
(safe-assert (fx= (length new-subst*) (length subst0*)))
new-subst*)))
(define find-match
(lambda (b1 ht)
(and (iffalse (worthwhile-size? (binding-size b1)) (printf "skipping b1: under worthwhile size ~s ~s\n" (binding-size b1) worthwhile-size))
(ormap (lambda (b2)
(iffalse #f (printf "checking ~s & ~s:" (prelex-name (binding-x b1)) (prelex-name (binding-x b2))))
(nanopass-case (Lcommonize1 Expr) (binding-e b1)
; NB: restricting to one clause for now...handling multiple
; NB: clauses should be straightforward with a helper per
; NB: common clause.
[(case-lambda ,preinfo1 (clause (,x1* ...) ,interface1 ,body1))
; NB: no rest interface for now. should be straightforward
(guard (fxnonnegative? interface1))
(and
(nanopass-case (Lcommonize1 Expr) (binding-e b2)
[(case-lambda ,preinfo2 (clause (,x2* ...) ,interface2 ,body2))
(guard (fxnonnegative? interface2))
(let-values ([(e subst*) (unify body1 body2)])
(and e
(iffalse (worthwhile-ratio? (binding-size b1) (length subst*)) (printf " no, not worthwhile ratio ~s ~s\n" (binding-size b1) (length subst*)))
(let ([subst* (sort-substs subst* x1* x2*)])
(iffalse #f (printf " yes\n"))
(make-frob subst* e b2))))]
[else (iffalse #f (printf " no, b2 does not meet lambda restrictions\n"))]))]
[else (iffalse #f (printf " no, b1 does not meet lambda restrictions\n"))]))
(hashtable-ref ht (binding-size b1) '())))))
(define record-helper!
(lambda (b next e*)
(binding-helper-b-set! b next)
(binding-helper-arg*-set! b e*)))
(define build-helper
(lambda (t t* body size helper-box)
(make-binding t
(with-output-language (Lcommonize1 Expr)
`(case-lambda ,(make-preinfo-lambda) (clause (,t* ...) ,(length t*) ,body)))
size
helper-box)))
(define commonize-letrec
(lambda (x* e* size* body) ; e* and body have not been processed
(define (prune-and-process! b)
(let ([b* (remq b (hashtable-ref ht (binding-size b) '()))])
(if (null? b*)
(hashtable-delete! ht (binding-size b))
(hashtable-set! ht (binding-size b) b*)))
(unless (binding-helper-b b) (binding-e-set! b (Expr (binding-e b)))))
(if (null? x*)
body
(let ([helper-box (box '())])
(let ([b* (map (lambda (x e size) (make-binding x e size helper-box)) x* e* size*)])
(let ([body (let f ([b* b*])
(if (null? b*)
(Expr body)
(let ([b (car b*)])
(let ([frob (find-match b ht)])
(if frob
(let* ([outer-b (frob-b frob)]
[helper-box (binding-helper-box outer-b)]
[helper-b (let ([t (make-prelex* (make-sym (binding-x b) "&" (binding-x outer-b)))])
(build-helper t (map subst-t (frob-subst* frob)) (frob-e frob) (binding-size outer-b) helper-box))])
(set-box! helper-box (cons helper-b (unbox helper-box)))
(record-helper! b helper-b (map subst-e1 (frob-subst* frob)))
(record-helper! outer-b helper-b (map subst-e2 (frob-subst* frob)))
(hashtable-update! ht (binding-size outer-b) (lambda (b*) (cons helper-b (remq outer-b b*))) '())
(f (cdr b*)))
(begin
(hashtable-update! ht (binding-size b) (lambda (b*) (cons b b*)) '())
(let ([body (f (cdr b*))])
(prune-and-process! b)
body)))))))])
(let ([helper-b* (unbox helper-box)])
(for-each prune-and-process! helper-b*)
(with-output-language (Lcommonize2 Expr)
`(letrec (,helper-b* ...) (,b* ...) ,body))))))))))
(Expr : Expr (ir) -> Expr ()
[(letrec ([,x* ,e* ,size*] ...) ,body)
; only unassigned lambda bindings post-cpletrec
(safe-assert (andmap (lambda (x) (not (prelex-assigned x))) x*))
(safe-assert (andmap (lambda (e) (Lcommonize1-lambda? e)) e*))
(commonize-letrec x* e* size* body)]
[(letrec* ([,x* ,e*] ...) ,body)
; no letrec* run post-cpletrec
(assert #f)]))
(define-pass cpcommonize2 : Lcommonize2 (ir) -> Lsrc ()
(definitions
(define build-caller
(lambda (e helper-b helper-arg*)
(define-who Arg
(lambda (e)
(with-output-language (Lsrc Expr)
(nanopass-case (Lcommonize1 Expr) e
[(ref ,maybe-src ,x) `(ref ,maybe-src ,x)]
[(quote ,d) `(quote ,d)]
[else (sorry! who "unexpected helper arg ~s" e)]))))
(define propagate
(lambda (alist)
(lambda (e)
(nanopass-case (Lsrc Expr) e
[(ref ,maybe-src ,x)
(cond
[(assq x alist) => cdr]
[else e])]
[else e]))))
(nanopass-case (Lcommonize1 Expr) e
[(case-lambda ,preinfo (clause (,x* ...) ,interface ,body))
(with-output-language (Lsrc Expr)
`(case-lambda ,preinfo
(clause (,x* ...) ,interface
,(let loop ([helper-b helper-b] [e* (map Arg helper-arg*)])
(if (binding-helper-b helper-b)
(nanopass-case (Lcommonize1 Expr) (binding-e helper-b)
[(case-lambda ,preinfo (clause (,x* ...) ,interface ,body))
(loop (binding-helper-b helper-b) (map (propagate (map cons x* e*)) (map Arg (binding-helper-arg* helper-b))))])
`(call ,(make-preinfo)
,(let ([t (binding-x helper-b)])
(if (prelex-referenced t)
(set-prelex-multiply-referenced! t #t)
(set-prelex-referenced! t #t))
`(ref #f ,t))
,e* ...))))))])))
(define maybe-build-caller
(lambda (b)
(let ([helper-b (binding-helper-b b)] [e (binding-e b)])
(if helper-b
(build-caller e helper-b (binding-helper-arg* b))
(Expr e))))))
(Expr : Expr (ir) -> Expr ()
[(letrec (,helper-b* ...) (,b* ...) ,[body])
(let loop ([rb* (reverse helper-b*)] [x* (map binding-x b*)] [e* (map maybe-build-caller b*)])
(if (null? rb*)
`(letrec ([,x* ,e*] ...) ,body)
(let ([b (car rb*)] [rb* (cdr rb*)])
(if (prelex-referenced (binding-x b))
(loop rb* (cons (binding-x b) x*) (cons (maybe-build-caller b) e*))
(loop rb* x* e*)))))]))
(lambda (x)
(let ([level (commonization-level)])
(if (fx= level 0)
x
(let ([worthwhile-size (expt 2 (fx- 10 level))])
(cpcommonize2 (cpcommonize1 (cpcommonize0 x) worthwhile-size))))))))
)