From: Andy Wingo <wingo@pobox.com>
Date: Thu, 12 Mar 2015 13:48:03 +0000 (+0100)
Subject: Only lazily compile where profitable
X-Git-Url: https://git.hcoop.net/bpt/guile.git/commitdiff_plain/fe7ecee8204fa79bfebcc925b82e1e670ed34cea

Only lazily compile where profitable

* module/ice-9/eval.scm (primitive-eval): Only lazily compile box-ref on
  toplevel variables; otherwise compile eagerly to avoid the
  indirection.
---

diff --git a/module/ice-9/eval.scm b/module/ice-9/eval.scm
index f5bcc16b4..3b68f07ae 100644
--- a/module/ice-9/eval.scm
+++ b/module/ice-9/eval.scm
@@ -213,11 +213,12 @@
                            '()
                            (cons ((car args) env) (lp (cdr args)))))))))))))
 
-  (define (compile-box-ref cenv box)
+  (define (compile-box-ref box)
     (match box
       ((,(typecode resolve) . loc)
-       (let ((var (%resolve-variable loc (env-toplevel cenv))))
-         (lambda (env) (variable-ref var))))
+       (lazy (cenv)
+         (let ((var (%resolve-variable loc (env-toplevel cenv))))
+           (lambda (env) (variable-ref var)))))
       ((,(typecode lexical-ref) depth . width)
        (lambda (env)
          (variable-ref (env-ref env depth width))))
@@ -655,7 +656,7 @@
        (compile-call f args))
       
       ((,(typecode box-ref) . box)
-       (lazy (env) (compile-box-ref env box)))
+       (compile-box-ref box))
 
       ((,(typecode resolve) . loc)
        (lazy (env) (compile-resolve env loc)))