summaryrefslogtreecommitdiff
path: root/sysdeps/m68k/m68020/add_n.S
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/m68k/m68020/add_n.S')
-rw-r--r--sysdeps/m68k/m68020/add_n.S76
1 files changed, 76 insertions, 0 deletions
diff --git a/sysdeps/m68k/m68020/add_n.S b/sysdeps/m68k/m68020/add_n.S
new file mode 100644
index 0000000000..ea7a4458ea
--- /dev/null
+++ b/sysdeps/m68k/m68020/add_n.S
@@ -0,0 +1,76 @@
+/* mc68020 __mpn_add_n -- Add two limb vectors of the same length > 0 and store
+ sum in a third limb vector.
+
+Copyright (C) 1992, 1994 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 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+/*
+ INPUT PARAMETERS
+ res_ptr (sp + 4)
+ s1_ptr (sp + 8)
+ s2_ptr (sp + 16)
+ size (sp + 12)
+*/
+
+#include "asm-syntax.h"
+
+ TEXT
+ ALIGN
+ GLOBL ___mpn_add_n
+
+LAB(___mpn_add_n)
+/* Save used registers on the stack. */
+ INSN2(move,l ,MEM_PREDEC(sp),d2)
+ INSN2(move,l ,MEM_PREDEC(sp),a2)
+
+/* Copy the arguments to registers. Better use movem? */
+ INSN2(move,l ,a2,MEM_DISP(sp,12))
+ INSN2(move,l ,a0,MEM_DISP(sp,16))
+ INSN2(move,l ,a1,MEM_DISP(sp,20))
+ INSN2(move,l ,d2,MEM_DISP(sp,24))
+
+ INSN2(eor,w ,d2,#1)
+ INSN2(lsr,l ,d2,#1)
+ bcc L1
+ INSN2(subq,l ,d2,#1) /* clears cy as side effect */
+
+LAB(Loop)
+ INSN2(move,l ,d0,MEM_POSTINC(a0))
+ INSN2(move,l ,d1,MEM_POSTINC(a1))
+ INSN2(addx,l ,d0,d1)
+ INSN2(move,l ,MEM_POSTINC(a2),d0)
+LAB(L1) INSN2(move,l ,d0,MEM_POSTINC(a0))
+ INSN2(move,l ,d1,MEM_POSTINC(a1))
+ INSN2(addx,l ,d0,d1)
+ INSN2(move,l ,MEM_POSTINC(a2),d0)
+
+ dbf d2,Loop /* loop until 16 lsb of %4 == -1 */
+ INSN2(subx,l ,d0,d0) /* d0 <= -cy; save cy as 0 or -1 in d0 */
+ INSN2(sub,l ,d2,#0x10000)
+ bcs L2
+ INSN2(add,l ,d0,d0) /* restore cy */
+ bra Loop
+
+LAB(L2)
+ INSN1(neg,l ,d0)
+
+/* Restore used registers from stack frame. */
+ INSN2(move,l ,a2,MEM_POSTINC(sp))
+ INSN2(move,l ,d2,MEM_POSTINC(sp))
+
+ rts