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diff --git a/sysdeps/s390/s390-32/sub_n.S b/sysdeps/s390/s390-32/sub_n.S
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+/* __mpn_sub_n -- Add two limb vectors of the same length > 0 and store
+   sum in a third limb vector.
+   Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+   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 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 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 Library General Public
+   License for more details.
+
+   You should have received a copy of the GNU Library 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. */
+
+/*
+  INPUT PARAMETERS
+  res_ptr	%r2
+  s1_ptr	%r3
+  s2_ptr	%r4
+  size		%r5
+*/
+
+#include "sysdep.h"
+#include "asm-syntax.h"
+
+ENTRY(__mpn_sub_n)
+	st     %r6,24(%r15)   # save register 6
+	sr     %r1,%r1
+	lhi    %r0,1          # cannot use ahi to add carry, use slr
+.L0:    l      %r6,0(%r1,%r3) # .L0 -> no carry from last sub
+	sl     %r6,0(%r1,%r4)
+	st     %r6,0(%r1,%r2)
+	la     %r1,4(0,%r1)
+	brc    4,.L3
+.L1:    brct   %r5,.L0
+	slr    %r2,%r2        # no last carry to return
+	j      .Lexit
+.L2:    l      %r6,0(%r1,%r3) # .L2 -> carry from last sub
+	sl     %r6,0(%r1,%r4)
+	brc    4,.L4
+	slr    %r6,%r0        # no carry yet, add carry from last sub
+	st     %r6,0(%r1,%r2)
+	la     %r1,4(0,%r1)
+	brc    11,.L1         # new carry ?
+.L3:    brct   %r5,.L2
+	lr     %r2,%r0        # return last carry
+	j      .Lexit
+.L4:    slr    %r6,%r0        # already a carry, add carry from last sub
+	st     %r6,0(%r1,%r2)
+	la     %r1,4(0,%r1)
+	brct   %r5,.L2
+	lr     %r2,%r0        # return last carry
+.Lexit: l      %r6,24(%r15)   # restore register 6
+	br     %r14
+END(__mpn_sub_n)