Raymond Toy pushed to branch issue-276-xoroshiro128starstar at cmucl / cmucl

Commits: 39144242 by Raymond Toy at 2024-02-13T18:47:58-08:00 Implement random-state-jump for xoroshiro128**

Update the test for the new jump function.

- - - - -

3 changed files:

- src/code/rand-xoroshiro.lisp - src/i18n/locale/cmucl.pot - tests/rng.lisp

Changes:

===================================== src/code/rand-xoroshiro.lisp ===================================== @@ -496,6 +496,7 @@

;; Jump function for the generator. See the jump function in ;; http://xoroshiro.di.unimi.it/xoroshiro128plus.c +#-x86 (defun random-state-jump (&optional (rng-state *random-state*)) _N"Jump the RNG-STATE. This is equivalent to 2^64 calls to the xoroshiro128+ generator. It can be used to generate 2^64 @@ -535,3 +536,44 @@ (setf (aref state 0) (convert s0-1 s0-0)) (setf (aref state 1) (convert s1-1 s1-0))) rng-state)) + +#+x86 +(defun random-state-jump (&optional (rng-state *random-state*)) + _N"Jump the RNG-STATE. This is equivalent to 2^64 calls to the + xoroshiro128** generator. It can be used to generate 2^64 + non-overlapping subsequences for parallel computations." + (declare (type random-state rng-state)) + (let ((state (random-state-state rng-state)) + (s0-0 0) + (s0-1 0) + (s1-0 0) + (s1-1 0)) + (declare (type (unsigned-byte 32) s0-0 s0-1 s1-0 s1-1) + (optimize (speed 3) (safety 0))) + ;; The constants are #xdf900294d8f554a5 and #x170865df4b3201fc, + ;; 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 '(#xdf900294d8f554a5 #x170865df4b3201fc)) + (declare (type (unsigned-byte 64) jump)) + (dotimes (b 64) + (declare (fixnum b)) + (when (logbitp b jump) + (multiple-value-bind (x1 x0) + (kernel:double-float-bits (aref state 0)) + (setf s0-1 (logxor s0-1 (ldb (byte 32 0) x1)) + s0-0 (logxor s0-0 x0))) + + (multiple-value-bind (x1 x0) + (kernel:double-float-bits (aref state 1)) + (setf s1-1 (logxor s1-1 (ldb (byte 32 0) x1)) + s1-0 (logxor s1-0 x0)))) + (xoroshiro-gen state))) + + (flet ((convert (x1 x0) + (declare (type (unsigned-byte 32) x1 x0)) + (kernel:make-double-float + (if (< x1 #x80000000) x1 (- x1 #x100000000)) + x0))) + (setf (aref state 0) (convert s0-1 s0-0)) + (setf (aref state 1) (convert s1-1 s1-0))) + rng-state))

===================================== src/i18n/locale/cmucl.pot ===================================== @@ -12237,6 +12237,13 @@ msgid "" " non-overlapping subsequences for parallel computations." msgstr ""

+#: src/code/rand-xoroshiro.lisp +msgid "" +"Jump the RNG-STATE. This is equivalent to 2^64 calls to the\n" +" xoroshiro128** generator. It can be used to generate 2^64\n" +" non-overlapping subsequences for parallel computations." +msgstr "" + #: src/code/ntrace.lisp msgid "" "This is bound to the returned values when evaluating :BREAK-AFTER and\n"

===================================== tests/rng.lisp ===================================== @@ -81,10 +81,16 @@ (kernel::make-random-object :state (kernel::init-random-state #x12345678) :rand 0 :cached-p nil)) - (dolist (result '((#x291ddf8e6f6a7b67 #x1f9018a12f9e031f) - (#x88a7aa12158558d0 #xe264d785ab1472d9) - (#x207e16f73c51e7ba #x999c8a0a9a8d87c0) - (#x28f8959d3bcf5ff1 #x38091e563ab6eb98))) + (dolist (result + #-x86 '((#x291ddf8e6f6a7b67 #x1f9018a12f9e031f) + (#x88a7aa12158558d0 #xe264d785ab1472d9) + (#x207e16f73c51e7ba #x999c8a0a9a8d87c0) + (#x28f8959d3bcf5ff1 #x38091e563ab6eb98)) + #+x86 '((#x19a22191480b0a4e #x43b3d7ee592dd4cf) + (#x76cb87035d0b6e99 #xb6827bcf2ef8267c) + (#x5125201dbdf76860 #x8984c075043869e2) + (#x2c06f0667255309f #xa48cbe2e60fc1d65) + )) (kernel:random-state-jump *test-state*) (assert-equal result (multiple-value-list (64-bit-rng-state *test-state*)))))

View it on GitLab: https://gitlab.common-lisp.net/cmucl/cmucl/-/commit/3914424237eb1ad708c7da58...