mirror/guile
mirror/guile
1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-06-10 05:50:26 +02:00
Code Activity

Minor CSE run-time optimization

Browse source 
* module/language/cps/cse.scm (compute-equivalent-subexpressions): Minor
  optimization to reduce the size of equivalent expression keys, and to
  avoid some work if an expression has no key.
This commit is contained in:
Andy Wingo 2017-11-30 10:41:45 +01:00
parent bfe70b129c
commit 1575c863fe
1 changed files with 56 additions and 55 deletions
Download patch file Download diff file Expand all files Collapse all files

23
module/language/cps/cse.scm
View file

@ -250,9 +250,9 @@ false. It could be that both true and false proofs are available."
(($ $call proc args) #f) (($ $call proc args) #f)
(($ $callk k proc args) #f) (($ $callk k proc args) #f)
(($ $primcall name param args) (($ $primcall name param args)
(cons* 'primcall name param (subst-vars var-substs args))) (cons* name param (subst-vars var-substs args)))
(($ $branch _ ($ $primcall name param args)) (($ $branch _ ($ $primcall name param args))
(cons* 'primcall name param (subst-vars var-substs args))) (cons* name param (subst-vars var-substs args)))
(($ $values args) #f) (($ $values args) #f)
(($ $prompt escape? tag handler) #f))) (($ $prompt escape? tag handler) #f)))
@ -271,16 +271,16 @@ false. It could be that both true and false proofs are available."
((def <- op arg ...) (aux <- op* arg* ...) ...) ((def <- op arg ...) (aux <- op* arg* ...) ...)
. clauses) . clauses)
(match exp-key (match exp-key
(('primcall 'op arg ...) (('op arg ...)
(match defs (match defs
((def) (add-def! (list 'primcall 'op* arg* ...) aux) ...))) ((def) (add-def! (list 'op* arg* ...) aux) ...)))
(_ (add-definitions . clauses)))) (_ (add-definitions . clauses))))
((add-definitions ((add-definitions
((op arg ...) (aux <- op* arg* ...) ...) ((op arg ...) (aux <- op* arg* ...) ...)
. clauses) . clauses)
(match exp-key (match exp-key
(('primcall 'op arg ...) (('op arg ...)
(add-def! (list 'primcall 'op* arg* ...) aux) ...) (add-def! (list 'op* arg* ...) aux) ...)
(_ (add-definitions . clauses)))))) (_ (add-definitions . clauses))))))
(add-definitions (add-definitions
((b <- box #f o) (o <- box-ref #f b)) ((b <- box #f o) (o <- box-ref #f b))
@ -319,8 +319,10 @@ false. It could be that both true and false proofs are available."
(define (visit-label label equiv-labels var-substs) (define (visit-label label equiv-labels var-substs)
(match (intmap-ref conts label) (match (intmap-ref conts label)
(($ $kargs names vars ($ $continue k src exp)) (($ $kargs names vars ($ $continue k src exp))
(let* ((exp-key (compute-exp-key var-substs exp)) (match (compute-exp-key var-substs exp)
(equiv (hash-ref equiv-set exp-key '())) (#f (values equiv-labels var-substs))
(exp-key
(let* ((equiv (hash-ref equiv-set exp-key '()))
(fx (intmap-ref effects label)) (fx (intmap-ref effects label))
(avail (intmap-ref avail label))) (avail (intmap-ref avail label)))
(define (finish equiv-labels var-substs) (define (finish equiv-labels var-substs)
@ -341,8 +343,7 @@ false. It could be that both true and false proofs are available."
;; be eliminated by CSE (though DCE might do it ;; be eliminated by CSE (though DCE might do it
;; if the value proves to be unused, in the ;; if the value proves to be unused, in the
;; allocation case). ;; allocation case).
(when (and exp-key (when (and (not (causes-effect? fx &allocation))
(not (causes-effect? fx &allocation))
(not (effect-clobbers? fx (&read-object &fluid)))) (not (effect-clobbers? fx (&read-object &fluid))))
(let ((defs (and (intset-ref singly-referenced k) (let ((defs (and (intset-ref singly-referenced k)
(intmap-ref defs label)))) (intmap-ref defs label))))
@ -367,7 +368,7 @@ false. It could be that both true and false proofs are available."
(fold (lambda (def var var-substs) (fold (lambda (def var var-substs)
(intmap-add var-substs def var)) (intmap-add var-substs def var))
var-substs defs vars) var-substs defs vars)
var-substs)))))))))) var-substs))))))))))))
(_ (values equiv-labels var-substs)))) (_ (values equiv-labels var-substs))))
;; Traverse the labels in fun in reverse post-order, which will ;; Traverse the labels in fun in reverse post-order, which will