Reorganisation of the source tree

Most of the other users of the fptools build system have migrated to
Cabal, and with the move to darcs we can now flatten the source tree
without losing history, so here goes.

The main change is that the ghc/ subdir is gone, and most of what it
contained is now at the top level.  The build system now makes no
pretense at being multi-project, it is just the GHC build system.

No doubt this will break many things, and there will be a period of
instability while we fix the dependencies.  A straightforward build
should work, but I haven't yet fixed binary/source distributions.
Changes to the Building Guide will follow, too.

1 files changed, 167 insertions, 0 deletions

diff --git a/rts/gmp/mpn/generic/addsub_n.c b/rts/gmp/mpn/generic/addsub_n.c
new file mode 100644
index 0000000000..c9bab3ef60
--- /dev/null
+++ b/rts/gmp/mpn/generic/addsub_n.c
@@ -0,0 +1,167 @@
+/* mpn_addsub_n -- Add and Subtract two limb vectors of equal, non-zero length.
+
+Copyright (C) 1999, 2000 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, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+#ifndef L1_CACHE_SIZE
+#define L1_CACHE_SIZE 8192	/* only 68040 has less than this */
+#endif
+
+#define PART_SIZE (L1_CACHE_SIZE / BYTES_PER_MP_LIMB / 6)
+
+
+/* mpn_addsub_n.
+   r1[] = s1[] + s2[]
+   r2[] = s1[] - s2[]
+   All operands have n limbs.
+   In-place operations allowed.  */
+mp_limb_t
+#if __STDC__
+mpn_addsub_n (mp_ptr r1p, mp_ptr r2p, mp_srcptr s1p, mp_srcptr s2p, mp_size_t n)
+#else
+mpn_addsub_n (r1p, r2p, s1p, s2p, n)
+     mp_ptr r1p, r2p;
+     mp_srcptr s1p, s2p;
+     mp_size_t n;
+#endif
+{
+  mp_limb_t acyn, acyo;		/* carry for add */
+  mp_limb_t scyn, scyo;		/* carry for subtract */
+  mp_size_t off;		/* offset in operands */
+  mp_size_t this_n;		/* size of current chunk */
+
+  /* We alternatingly add and subtract in chunks that fit into the (L1)
+     cache.  Since the chunks are several hundred limbs, the function call
+     overhead is insignificant, but we get much better locality.  */
+
+  /* We have three variant of the inner loop, the proper loop is chosen
+     depending on whether r1 or r2 are the same operand as s1 or s2.  */
+
+  if (r1p != s1p && r1p != s2p)
+    {
+      /* r1 is not identical to either input operand.  We can therefore write
+	 to r1 directly, without using temporary storage.  */
+      acyo = 0;
+      scyo = 0;
+      for (off = 0; off < n; off += PART_SIZE)
+	{
+	  this_n = MIN (n - off, PART_SIZE);
+#if HAVE_NATIVE_mpn_add_nc || !HAVE_NATIVE_mpn_add_n
+	  acyo = mpn_add_nc (r1p + off, s1p + off, s2p + off, this_n, acyo);
+#else
+	  acyn = mpn_add_n (r1p + off, s1p + off, s2p + off, this_n);
+	  acyo = acyn + mpn_add_1 (r1p + off, r1p + off, this_n, acyo);
+#endif
+#if HAVE_NATIVE_mpn_sub_nc || !HAVE_NATIVE_mpn_sub_n
+	  scyo = mpn_sub_nc (r2p + off, s1p + off, s2p + off, this_n, scyo);
+#else
+	  scyn = mpn_sub_n (r2p + off, s1p + off, s2p + off, this_n);
+	  scyo = scyn + mpn_sub_1 (r2p + off, r2p + off, this_n, scyo);
+#endif
+	}
+    }
+  else if (r2p != s1p && r2p != s2p)
+    {
+      /* r2 is not identical to either input operand.  We can therefore write
+	 to r2 directly, without using temporary storage.  */
+      acyo = 0;
+      scyo = 0;
+      for (off = 0; off < n; off += PART_SIZE)
+	{
+	  this_n = MIN (n - off, PART_SIZE);
+#if HAVE_NATIVE_mpn_sub_nc || !HAVE_NATIVE_mpn_sub_n
+	  scyo = mpn_sub_nc (r2p + off, s1p + off, s2p + off, this_n, scyo);
+#else
+	  scyn = mpn_sub_n (r2p + off, s1p + off, s2p + off, this_n);
+	  scyo = scyn + mpn_sub_1 (r2p + off, r2p + off, this_n, scyo);
+#endif
+#if HAVE_NATIVE_mpn_add_nc || !HAVE_NATIVE_mpn_add_n
+	  acyo = mpn_add_nc (r1p + off, s1p + off, s2p + off, this_n, acyo);
+#else
+	  acyn = mpn_add_n (r1p + off, s1p + off, s2p + off, this_n);
+	  acyo = acyn + mpn_add_1 (r1p + off, r1p + off, this_n, acyo);
+#endif
+	}
+    }
+  else
+    {
+      /* r1 and r2 are identical to s1 and s2 (r1==s1 and r2=s2 or vice versa)
+	 Need temporary storage.  */
+      mp_limb_t tp[PART_SIZE];
+      acyo = 0;
+      scyo = 0;
+      for (off = 0; off < n; off += PART_SIZE)
+	{
+	  this_n = MIN (n - off, PART_SIZE);
+#if HAVE_NATIVE_mpn_add_nc || !HAVE_NATIVE_mpn_add_n
+	  acyo = mpn_add_nc (tp, s1p + off, s2p + off, this_n, acyo);
+#else
+	  acyn = mpn_add_n (tp, s1p + off, s2p + off, this_n);
+	  acyo = acyn + mpn_add_1 (tp, tp, this_n, acyo);
+#endif
+#if HAVE_NATIVE_mpn_sub_nc || !HAVE_NATIVE_mpn_sub_n
+	  scyo = mpn_sub_nc (r2p + off, s1p + off, s2p + off, this_n, scyo);
+#else
+	  scyn = mpn_sub_n (r2p + off, s1p + off, s2p + off, this_n);
+	  scyo = scyn + mpn_sub_1 (r2p + off, r2p + off, this_n, scyo);
+#endif
+	  MPN_COPY (r1p + off, tp, this_n);
+	}
+    }
+
+  return 2 * acyo + scyo;
+}
+
+#ifdef MAIN
+#include <stdlib.h>
+#include <stdio.h>
+#include "timing.h"
+
+long cputime ();
+
+int
+main (int argc, char **argv)
+{
+  mp_ptr r1p, r2p, s1p, s2p;
+  double t;
+  mp_size_t n;
+
+  n = strtol (argv[1], 0, 0);
+
+  r1p = malloc (n * BYTES_PER_MP_LIMB);
+  r2p = malloc (n * BYTES_PER_MP_LIMB);
+  s1p = malloc (n * BYTES_PER_MP_LIMB);
+  s2p = malloc (n * BYTES_PER_MP_LIMB);
+  TIME (t,(mpn_add_n(r1p,s1p,s2p,n),mpn_sub_n(r1p,s1p,s2p,n)));
+  printf ("              separate add and sub: %.3f\n", t);
+  TIME (t,mpn_addsub_n(r1p,r2p,s1p,s2p,n));
+  printf ("combined addsub separate variables: %.3f\n", t);
+  TIME (t,mpn_addsub_n(r1p,r2p,r1p,s2p,n));
+  printf ("        combined addsub r1 overlap: %.3f\n", t);
+  TIME (t,mpn_addsub_n(r1p,r2p,r1p,s2p,n));
+  printf ("        combined addsub r2 overlap: %.3f\n", t);
+  TIME (t,mpn_addsub_n(r1p,r2p,r1p,r2p,n));
+  printf ("          combined addsub in-place: %.3f\n", t);
+
+  return 0;
+}
+#endif