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+(in-package #:mulk.objective-cl)
+
+;;; This file is for hacks that we might not want to actually use in a
+;;; production environment but which might be useful in determining
+;;; performance bottlenecks.  These hacks may depend on specific
+;;; versions of third-party libraries such as CFFI.
+
+
+;;; The following hack depends on a specific CFFI snapshot.  It tries to
+;;; alleviate the apparent slowness of CFFI::PARSE-TYPE in that
+;;; particular snapshot.
+;;;
+;;; The performance improvement for method calls accomplished by this
+;;; hack amounts to approximately 80 % for PRIMITIVE-INVOKE and
+;;; approximately 50 % for INVOKE.
+#+(or)
+(progn
+  (defparameter *cffi-hacked* nil)
+  (eval-when (:load-toplevel)
+    ;; If we do this more than once, we cache our own cached function,
+    ;; which is kind of useless.
+    (unless *cffi-hacked*
+      (setq *cffi-hacked* t)
+      (let ((original-cffi-parse-type-fn (fdefinition 'cffi::parse-type)))
+        (define-cached-function cffi::parse-type (type)
+            type
+          (funcall original-cffi-parse-type-fn type))))))