Not yet completed changes to support PPC

4 files changed, 205 insertions, 36 deletions

diff --git a/mpi/generic/distfiles b/mpi/generic/distfiles
index 02a1ca4c..0bf4600f 100644
--- a/mpi/generic/distfiles
+++ b/mpi/generic/distfiles
@@ -5,4 +5,5 @@ mpih-mul3.c
 mpih-lshift.c
 mpih-rshift.c
 mpih-sub1.c
+udiv-w-sdiv.c
 
diff --git a/mpi/generic/mpih-shift.c b/mpi/generic/mpih-lshift.c
index 2da2edd7..698cd38d 100644
--- a/mpi/generic/mpih-shift.c
+++ b/mpi/generic/mpih-lshift.c
@@ -1,6 +1,5 @@
-/* mpihelp-shift.c  -  MPI helper functions
- *	Copyright (c) 1997 by Werner Koch (dd9jn)
- *	Copyright (C) 1994, 1996 Free Software Foundation, Inc.
+/* mpihelp-lshift.c  -	MPI helper functions
+ *	Copyright (C) 1994, 1996, 1998 Free Software Foundation, Inc.
  *
  * This file is part of G10.
  *
@@ -68,36 +67,3 @@ mpihelp_lshift( mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
 }
 
 
-/* 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.
- */
-
-mpi_limb_t
-mpihelp_rshift( mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned cnt)
-{
-    mpi_limb_t high_limb, low_limb;
-    unsigned sh_1, sh_2;
-    mpi_size_t i;
-    mpi_limb_t retval;
-
-    sh_1 = cnt;
-    wp -= 1;
-    sh_2 = BITS_PER_MPI_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;
-}
-
diff --git a/mpi/generic/mpih-rshift.c b/mpi/generic/mpih-rshift.c
new file mode 100644
index 00000000..d8ca35f1
--- /dev/null
+++ b/mpi/generic/mpih-rshift.c
@@ -0,0 +1,67 @@
+/* mpih-rshift.c  -  MPI helper functions
+ *	Copyright (C) 1994, 1996, 1998 Free Software Foundation, Inc.
+ *
+ * This file is part of GNUPG
+ *
+ * GNUPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GNUPG 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ *
+ * Note: This code is heavily based on the GNU MP Library.
+ *	 Actually it's the same code with only minor changes in the
+ *	 way the data is stored; this is to support the abstraction
+ *	 of an optional secure memory allocation which may be used
+ *	 to avoid revealing of sensitive data due to paging etc.
+ *	 The GNU MP Library itself is published under the LGPL;
+ *	 however I decided to publish this code under the plain GPL.
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "mpi-internal.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.
+ */
+
+mpi_limb_t
+mpihelp_rshift( mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned cnt)
+{
+    mpi_limb_t high_limb, low_limb;
+    unsigned sh_1, sh_2;
+    mpi_size_t i;
+    mpi_limb_t retval;
+
+    sh_1 = cnt;
+    wp -= 1;
+    sh_2 = BITS_PER_MPI_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;
+}
+
diff --git a/mpi/generic/udiv-w-sdiv.c b/mpi/generic/udiv-w-sdiv.c
new file mode 100644
index 00000000..7ffec099
--- /dev/null
+++ b/mpi/generic/udiv-w-sdiv.c
@@ -0,0 +1,135 @@
+/* mpihelp_udiv_w_sdiv -- implement udiv_qrnnd on machines with only signed
+ *			  division.
+ *
+ * Contributed by Peter L. Montgomery.
+ *
+ * Copyright (C) 1992, 1994, 1996, 1998 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "mpi-internal.h"
+#include "longlong.h"
+
+
+#if 0  /* not yet ported to MPI */
+
+mpi_limb_t
+mpihelp_udiv_w_sdiv( mpi_limp_t *rp,
+		     mpi_limp_t *a1,
+		     mpi_limp_t *a0,
+		     mpi_limp_t *d   )
+{
+  mp_limb_t q, r;
+  mp_limb_t c0, c1, b1;
+
+  if ((mpi_limb_signed_t) d >= 0)
+    {
+      if (a1 < d - a1 - (a0 >> (BITS_PER_MP_LIMB - 1)))
+	{
+	  /* dividend, divisor, and quotient are nonnegative */
+	  sdiv_qrnnd (q, r, a1, a0, d);
+	}
+      else
+	{
+	  /* Compute c1*2^32 + c0 = a1*2^32 + a0 - 2^31*d */
+	  sub_ddmmss (c1, c0, a1, a0, d >> 1, d << (BITS_PER_MP_LIMB - 1));
+	  /* Divide (c1*2^32 + c0) by d */
+	  sdiv_qrnnd (q, r, c1, c0, d);
+	  /* Add 2^31 to quotient */
+	  q += (mp_limb_t) 1 << (BITS_PER_MP_LIMB - 1);
+	}
+    }
+  else
+    {
+      b1 = d >> 1;			/* d/2, between 2^30 and 2^31 - 1 */
+      c1 = a1 >> 1;			/* A/2 */
+      c0 = (a1 << (BITS_PER_MP_LIMB - 1)) + (a0 >> 1);
+
+      if (a1 < b1)			/* A < 2^32*b1, so A/2 < 2^31*b1 */
+	{
+	  sdiv_qrnnd (q, r, c1, c0, b1); /* (A/2) / (d/2) */
+
+	  r = 2*r + (a0 & 1);		/* Remainder from A/(2*b1) */
+	  if ((d & 1) != 0)
+	    {
+	      if (r >= q)
+		r = r - q;
+	      else if (q - r <= d)
+		{
+		  r = r - q + d;
+		  q--;
+		}
+	      else
+		{
+		  r = r - q + 2*d;
+		  q -= 2;
+		}
+	    }
+	}
+      else if (c1 < b1) 		/* So 2^31 <= (A/2)/b1 < 2^32 */
+	{
+	  c1 = (b1 - 1) - c1;
+	  c0 = ~c0;			/* logical NOT */
+
+	  sdiv_qrnnd (q, r, c1, c0, b1); /* (A/2) / (d/2) */
+
+	  q = ~q;			/* (A/2)/b1 */
+	  r = (b1 - 1) - r;
+
+	  r = 2*r + (a0 & 1);		/* A/(2*b1) */
+
+	  if ((d & 1) != 0)
+	    {
+	      if (r >= q)
+		r = r - q;
+	      else if (q - r <= d)
+		{
+		  r = r - q + d;
+		  q--;
+		}
+	      else
+		{
+		  r = r - q + 2*d;
+		  q -= 2;
+		}
+	    }
+	}
+      else				/* Implies c1 = b1 */
+	{				/* Hence a1 = d - 1 = 2*b1 - 1 */
+	  if (a0 >= -d)
+	    {
+	      q = -1;
+	      r = a0 + d;
+	    }
+	  else
+	    {
+	      q = -2;
+	      r = a0 + 2*d;
+	    }
+	}
+    }
+
+  *rp = r;
+  return q;
+}
+
+#endif
+