Commit 0b94ee3d authored by Raymond Toy's avatar Raymond Toy
Browse files

Add custom xoro-random-state printer 

Custom printer to print the state as array of integers instead of
doubles.  Makes it easier to see and match what the C code does.
parent dbc0518d

src/code/rand-xoroshiro.lisp

+41 −8
Original line number Diff line number Diff line
@@ -79,6 +79,7 @@ 


(defstruct (xoro-random-state

	     (:constructor make-xoroshiro-object)

	     (:print-function %print-xoro-state)

	     (:make-load-form-fun :just-dump-it-normally))

  ;; The state of the RNG.  The actual algorithm uses 2 64-bit words

  ;; of state.  To reduce consing, we use an array of double-float's
@@ -95,6 +96,46 @@ 
  ;; generate a new 64-bit result.

  (cached-p nil :type (member t nil)))



(defun %print-xoro-state (rng-state stream depth)

  (declare (ignore depth))

  ;; Basically the same as the default structure printer, but we want

  ;; to print the state as an array of integers instead of doubles,

  ;; because it's a bit confusing to see the state as doubles.

  (let ((state (xoro-random-state-state rng-state)))

    (pprint-logical-block (stream nil :prefix "#S(" :suffix ")")

      (prin1 'xoro-random-state stream)

      (write-char #\space stream)

      (pprint-indent :block 2 stream)

      (pprint-newline :linear stream)

      (prin1 :state stream)

      (write-char #\space stream)

      (pprint-newline :miser stream)

      (pprint-logical-block (stream nil :prefix "#.(" :suffix ")")

	(prin1 'init-xoro-state stream)

	(write-char #\space stream)

	(prin1 (make-array 4 :element-type '(unsigned-byte 32)

			 :initial-contents (list (ldb (byte 32 0)

						      (double-float-high-bits (aref state 0)))

						 (double-float-low-bits (aref state 0))

						 (ldb (byte 32 0)

						      (double-float-high-bits (aref state 1)))

						 (double-float-low-bits (aref state 1))))

	       stream))

      (write-char #\space stream)

      (pprint-newline :linear stream)



      (prin1 :rand stream)

      (write-char #\space stream)

      (pprint-newline :miser stream)

      (prin1 (xoro-random-state-rand rng-state) stream)

      (write-char #\space stream)

      (pprint-newline :linear stream)



      (prin1 :cached-p stream)

      (write-char #\space stream)

      (pprint-newline :miser stream)

      (prin1 (xoro-random-state-cached-p rng-state) stream))))



(defvar *xoro-random-state*

  (make-xoroshiro-object))
@@ -396,11 +437,3 @@ 
      (setf (aref state 1) (convert s1-1 s1-0)))

      rng-state))

(defun print-xoro-state (rng-state)

  (let ((state (xoro-random-state-state rng-state)))

    (flet ((v (x)

	     (multiple-value-bind (hi lo)

		 (kernel:double-float-bits x)

	       (logior (ash (ldb (byte 32 0) hi) 32)

		       lo))))

      (format t "~16,'0x ~16,'0x" (v (aref state 0)) (v (aref state 1))))))
 
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