initial import

1 files changed, 94 insertions, 0 deletions

diff --git a/sysdeps/i386/sub_n.S b/sysdeps/i386/sub_n.S
new file mode 100644
index 0000000000..a1630d4562
--- /dev/null
+++ b/sysdeps/i386/sub_n.S
@@ -0,0 +1,94 @@
+/* i80386 __mpn_sub_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 + 12)
+  size		(sp + 16)
+*/
+
+#include "sysdep.h"
+#include "asm-syntax.h"
+
+.text
+	ALIGN (3)
+	.globl C_SYMBOL_NAME(__mpn_sub_n)
+C_SYMBOL_NAME(__mpn_sub_n:)
+	pushl %edi
+	pushl %esi
+
+	movl 12(%esp),%edi	/* res_ptr */
+	movl 16(%esp),%esi	/* s1_ptr */
+	movl 20(%esp),%edx	/* s2_ptr */
+	movl 24(%esp),%ecx	/* size */
+
+	movl	%ecx,%eax
+	shrl	$3,%ecx			/* compute count for unrolled loop */
+	negl	%eax
+	andl	$7,%eax			/* get index where to start loop */
+	jz	Loop			/* necessary special case for 0 */
+	incl	%ecx			/* adjust loop count */
+	shll	$2,%eax			/* adjustment for pointers... */
+	subl	%eax,%edi		/* ... since they are offset ... */
+	subl	%eax,%esi		/* ... by a constant when we ... */
+	subl	%eax,%edx		/* ... enter the loop */
+	shrl	$2,%eax			/* restore previous value */
+	leal	(Loop - 3)(%eax,%eax,8),%eax	/* calc start addr in loop */
+	jmp	*%eax			/* jump into loop */
+	ALIGN (3)
+Loop:	movl	(%esi),%eax
+	sbbl	(%edx),%eax
+	movl	%eax,(%edi)
+	movl	4(%esi),%eax
+	sbbl	4(%edx),%eax
+	movl	%eax,4(%edi)
+	movl	8(%esi),%eax
+	sbbl	8(%edx),%eax
+	movl	%eax,8(%edi)
+	movl	12(%esi),%eax
+	sbbl	12(%edx),%eax
+	movl	%eax,12(%edi)
+	movl	16(%esi),%eax
+	sbbl	16(%edx),%eax
+	movl	%eax,16(%edi)
+	movl	20(%esi),%eax
+	sbbl	20(%edx),%eax
+	movl	%eax,20(%edi)
+	movl	24(%esi),%eax
+	sbbl	24(%edx),%eax
+	movl	%eax,24(%edi)
+	movl	28(%esi),%eax
+	sbbl	28(%edx),%eax
+	movl	%eax,28(%edi)
+	leal	32(%edi),%edi
+	leal	32(%esi),%esi
+	leal	32(%edx),%edx
+	decl	%ecx
+	jnz	Loop
+
+	sbbl	%eax,%eax
+	negl	%eax
+
+	popl %esi
+	popl %edi
+	ret