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at 2017-12-27T09:46:59-08:00

Modify random-state-jump to use 32-bit ints

Break the constants in the jump function into 32-bit chunks so we
operate on 32-bit integers instead of 64-bit integers.

This is a minor optimization.

 	(s1-1 0))

     (declare (type (unsigned-byte 32) s0-0 s0-1 s1-0 s1-1)

 	     (optimize (speed 3) (safety 0)))

-    (dolist (jump '(#xbeac0467eba5facb #xd86b048b86aa9922))

-      (declare (type (unsigned-byte 64) jump))

-      (dotimes (b 64)

+    ;; The constants are #xbeac0467eba5facb and #xd86b048b86aa9922,

+    ;; and we process these numbers starting from the LSB.  We want ot

+    ;; process these in 32-bit chunks, so word-reverse the constants.

+    (dolist (jump '(#xeba5facb #xbeac0467 #x86aa9922 #xd86b048b))

+      (declare (type (unsigned-byte 32) jump))

+      (dotimes (b 32)

 	(declare (fixnum b))

 	(when (logbitp b jump)

 	  (multiple-value-bind (x1 x0)

Raymond Toy pushed to branch rtoy-xoro-default at cmucl / cmucl

Commits:

1 changed file:

Changes: