[armedbear-cvs] r11958 - trunk/abcl/src/org/armedbear/lisp

[Erik Huelsmann]

Author: ehuelsmann
Date: Wed May 27 02:12:40 2009
New Revision: 11958

Log:
Redoing my math homework:

   "x < y --> -x > -y"

Modified:
   trunk/abcl/src/org/armedbear/lisp/compiler-pass2.lisp

Modified: trunk/abcl/src/org/armedbear/lisp/compiler-pass2.lisp
==============================================================================
--- trunk/abcl/src/org/armedbear/lisp/compiler-pass2.lisp	(original)
+++ trunk/abcl/src/org/armedbear/lisp/compiler-pass2.lisp	Wed May 27 02:12:40 2009
@@ -6188,18 +6188,8 @@
 value for use with derive-type-minus and derive-type-plus.")
 
 (define-int-bounds-derivation - (low1 high1 low2 high2)
-  (values (when (and low1 high2) ;; low1 or high2 undefined: no lower bound
-            (if low2
-                (min (- low1 low2)
-                     (- low1 high2))
-                ;; low2 undefined: no effect on lower bound
-                (- low1 high2)))
-          (when (and high1 low2) ;; high1 or low2 undefined: no upper bound
-            (if high2
-                (max (- high1 low2)
-                     (- high1 high2))
-                ;; high2 undefined: no effect on upper bound
-                (- high1 low2)))))
+  (values (and low1 high2 (- low1 high2))
+          (and high1 low2 (- high2 low2))))
 
 (defun derive-compiler-types (args op)
   (flet ((combine (x y)