Prepare for radical source tree reorganization.zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 78 insertions, 0 deletions

diff --git a/REORG.TODO/stdlib/rshift.c b/REORG.TODO/stdlib/rshift.c
new file mode 100644
index 0000000000..d4c7f77769
--- /dev/null
+++ b/REORG.TODO/stdlib/rshift.c
@@ -0,0 +1,78 @@
+/* mpn_rshift -- Shift right a low-level natural-number integer.
+
+Copyright (C) 1991-2017 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The GNU MP Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library; see the file COPYING.LIB.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#include <gmp.h>
+#include "gmp-impl.h"
+
+#include <assert.h>
+
+/* Shift U (pointed to by UP and USIZE limbs long) CNT bits to the right
+   and store the USIZE least significant limbs of the result at WP.
+   The bits shifted out to the right are returned.
+
+   Argument constraints:
+   1. 0 < CNT < BITS_PER_MP_LIMB
+   2. If the result is to be written over the input, WP must be <= UP.
+*/
+
+mp_limb_t
+mpn_rshift (register mp_ptr wp,
+	    register mp_srcptr up, mp_size_t usize,
+	    register unsigned int cnt)
+{
+  register mp_limb_t high_limb, low_limb;
+  register unsigned sh_1, sh_2;
+  register mp_size_t i;
+  mp_limb_t retval;
+
+  assert (usize != 0 && cnt != 0);
+
+  sh_1 = cnt;
+
+#if 0
+  if (sh_1 == 0)
+    {
+      if (wp != up)
+	{
+	  /* Copy from low end to high end, to allow specified input/output
+	     overlapping.  */
+	  for (i = 0; i < usize; i++)
+	    wp[i] = up[i];
+	}
+      return usize;
+    }
+#endif
+
+  wp -= 1;
+  sh_2 = BITS_PER_MP_LIMB - sh_1;
+  high_limb = up[0];
+  retval = high_limb << sh_2;
+  low_limb = high_limb;
+
+  for (i = 1; i < usize; i++)
+    {
+      high_limb = up[i];
+      wp[i] = (low_limb >> sh_1) | (high_limb << sh_2);
+      low_limb = high_limb;
+    }
+  wp[i] = low_limb >> sh_1;
+
+  return retval;
+}