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+/* Add two limb vectors of equal, non-zero length for PowerPC.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C 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 <sysdep.h>
+
+/* mp_limb_t mpn_add_n (mp_ptr res_ptr, mp_srcptr s1_ptr, mp_srcptr s2_ptr,
+ mp_size_t size)
+ Calculate s1+s2 and put result in res_ptr; return carry, 0 or 1. */
+
+/* Note on optimisation: This code is optimal for the 601. Almost every other
+ possible 2-unrolled inner loop will not be. Also, watch out for the
+ alignment... */
+
+EALIGN(__mpn_add_n,3,0)
+/* Set up for loop below. */
+ mtcrf 0x01,%r6
+ srwi. %r7,%r6,1
+ li %r10,0
+ mtctr %r7
+ bt 31,2f
+
+/* Clear the carry. */
+ addic %r0,%r0,0
+/* Adjust pointers for loop. */
+ addi %r3,%r3,-4
+ addi %r4,%r4,-4
+ addi %r5,%r5,-4
+ b 0f
+
+2: lwz %r7,0(%r5)
+ lwz %r6,0(%r4)
+ addc %r6,%r6,%r7
+ stw %r6,0(%r3)
+ beq 1f
+
+/* The loop. */
+
+/* Align start of loop to an odd word boundary to guarantee that the
+ last two words can be fetched in one access (for 601). */
+0: lwz %r9,4(%r4)
+ lwz %r8,4(%r5)
+ lwzu %r6,8(%r4)
+ lwzu %r7,8(%r5)
+ adde %r8,%r9,%r8
+ stw %r8,4(%r3)
+ adde %r6,%r6,%r7
+ stwu %r6,8(%r3)
+ bdnz 0b
+/* Return the carry. */
+1: addze %r3,%r10
+ blr
+END(__mpn_add_n)