X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=OPTIMIZATIONS;h=a702c7d2ba18edf5f3899d312027286d0664fcdd;hb=7c7e6276719b8d40fddec2070cad81064a25c8ed;hp=50d3417bead8b8b8e1d755af8e66ed6b27ace877;hpb=9afd3958cf7b5ad829c61a4a85956cf783e500f5;p=sbcl.git

diff --git a/OPTIMIZATIONS b/OPTIMIZATIONS
index 50d3417..a702c7d 100644
--- a/OPTIMIZATIONS
+++ b/OPTIMIZATIONS
@@ -187,9 +187,9 @@ stack-allocation of structures is impossible.
 --------------------------------------------------------------------------------
 #21
 (defun-with-dx foo ()
-  (let ((dx (list (list 1 2) (list 3 4)
+  (let ((dx (list (list 1 2) (list 3 4))))
     (declare (dynamic-extent dx))
-    ...)))))
+    ...))
 
 External list in DX is allocated on stack, but internal are not.
 --------------------------------------------------------------------------------
@@ -204,16 +204,31 @@ a. Iterations on &REST lists, returning them as VALUES could be
    rewritten with &MORE vectors.
 b. Implement local unknown-values mv-call (useful for fast type checking).
 --------------------------------------------------------------------------------
-#25
-EQL is implemented generically in situations where this isn't necessary.
-
-(defun f (x y)
-  (declare (type (or symbol fixnum) x)
-	   (optimize speed (safety 0) (debug 0)))
-  (eql x y))
-
-SUBTYPEP is smart enough to determine that this type is a subtype
-of (and (or (not number) fixnum) (not character))
-
-This sitation where the type is (OR NULL FIXNUM) comes up
-in cl-bench, for example in the value returned by POSITION.
+#26
+SBCL cannot derive upper bound for I and uses generic arithmetic here:
+
+(defun foo (l)
+  (declare (vector l))
+  (dotimes (i (length l))
+    (if (block nil
+          (map-foo (lambda (x) (if x (return t)))
+                   l))
+        t
+        nil)))
+
+(So the constraint propagator or a possible future SSA-convertor
+should know the connection between an NLE and its CLEANUP.)
+--------------------------------------------------------------------------------
+#27
+Initialization of stack-allocated arrays is inefficient: we always
+fill the vector with zeroes, even when it is not needed (as for
+platforms with conservative GC or for arrays of unboxed objectes) and
+is performed later explicitely.
+--------------------------------------------------------------------------------
+#28
+a. Accessing raw slots in structure instances is more inefficient than
+it could be; if we placed raw slots before the header word, we would
+not need to do arithmetic at runtime to access them.  (But beware:
+this would complicate handling of the interior pointer).
+
+b. (Also note that raw slots are currently disabled on HPPA)
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