about summary refs log tree commit diff
path: root/sysdeps/s390/s390-64/sub_n.S
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/s390/s390-64/sub_n.S')
-rw-r--r--sysdeps/s390/s390-64/sub_n.S60
1 files changed, 60 insertions, 0 deletions
diff --git a/sysdeps/s390/s390-64/sub_n.S b/sysdeps/s390/s390-64/sub_n.S
new file mode 100644
index 0000000000..183ebb7fed
--- /dev/null
+++ b/sysdeps/s390/s390-64/sub_n.S
@@ -0,0 +1,60 @@
+/* __mpn_sub_n -- Add two limb vectors of the same length > 0 and store
+   sum in a third limb vector.  64 bit S/390 version.
+   Copyright (C) 2001 Free Software Foundation, Inc.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+   This file is part of the GNU MP 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.  */
+
+/* INPUT PARAMETERS
+     %r2 = res_ptr
+     %r3 = s1_ptr
+     %r4 = s2_ptr
+     %r5 = size.  */
+	
+#include "sysdep.h"
+#include "asm-syntax.h"
+
+ENTRY(__mpn_sub_n)
+        stg    %r6,48(%r15)   # save register 6
+        sgr    %r1,%r1
+        lghi   %r0,1          # cannot use ahi to add carry, use slr
+.L0:	lg     %r6,0(%r1,%r3) # .L0 -> no carry from last sub
+	slg    %r6,0(%r1,%r4)
+	stg    %r6,0(%r1,%r2)
+	la     %r1,8(%r1)
+	brc    4,.L3
+.L1:	brct   %r5,.L0
+	slgr   %r2,%r2	      # no last carry to return
+	j      .Lexit
+.L2:	lg     %r6,0(%r1,%r3) # .L2 -> carry from last sub
+	slg    %r6,0(%r1,%r4)
+	brc    4,.L4
+	slgr   %r6,%r0	      # no carry yet, add carry from last sub
+	stg    %r6,0(%r1,%r2)
+	la     %r1,8(%r1)
+	brc    11,.L1	      # new carry ?
+.L3:	brct   %r5,.L2
+	lgr    %r2,%r0	      # return last carry
+	j      .Lexit
+.L4:	slgr   %r6,%r0	      # already a carry, add carry from last sub
+	stg    %r6,0(%r1,%r2)
+	la     %r1,8(%r1)
+	brct   %r5,.L2
+	lgr    %r2,%r0	      # return last carry
+.Lexit: lg     %r6,48(%r15)   # restore register 6
+	br     %r14
+END(__mpn_sub_n)