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+/* Pentium __mpn_sub_n -- Subtract two limb vectors of the same length > 0
+ and store difference in a third limb vector.
+
+Copyright (C) 1992, 1994, 1995 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)
+*/
+
+#define r1 %eax
+#define r2 %edx
+#define src1 %esi
+#define src2 %ebp
+#define dst %edi
+#define x %ebx
+
+#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
+ pushl %ebx
+ pushl %ebp
+
+ movl 20(%esp),dst /* res_ptr */
+ movl 24(%esp),src1 /* s1_ptr */
+ movl 28(%esp),src2 /* s2_ptr */
+ movl 32(%esp),%ecx /* size */
+
+ movl (src2),x
+
+ decl %ecx
+ movl %ecx,r2
+ shrl $3,%ecx
+ andl $7,r2
+ testl %ecx,%ecx /* zero carry flag */
+ jz Lend
+ pushl r2
+
+ ALIGN (3)
+Loop: movl 28(dst),%eax /* fetch destination cache line */
+ leal 32(dst),dst
+
+L1: movl (src1),r1
+ movl 4(src1),r2
+ sbbl x,r1
+ movl 4(src2),x
+ sbbl x,r2
+ movl 8(src2),x
+ movl r1,-32(dst)
+ movl r2,-28(dst)
+
+L2: movl 8(src1),r1
+ movl 12(src1),r2
+ sbbl x,r1
+ movl 12(src2),x
+ sbbl x,r2
+ movl 16(src2),x
+ movl r1,-24(dst)
+ movl r2,-20(dst)
+
+L3: movl 16(src1),r1
+ movl 20(src1),r2
+ sbbl x,r1
+ movl 20(src2),x
+ sbbl x,r2
+ movl 24(src2),x
+ movl r1,-16(dst)
+ movl r2,-12(dst)
+
+L4: movl 24(src1),r1
+ movl 28(src1),r2
+ sbbl x,r1
+ movl 28(src2),x
+ sbbl x,r2
+ movl 32(src2),x
+ movl r1,-8(dst)
+ movl r2,-4(dst)
+
+ leal 32(src1),src1
+ leal 32(src2),src2
+ decl %ecx
+ jnz Loop
+
+ popl r2
+Lend:
+ decl r2 /* test r2 w/o clobbering carry */
+ js Lend2
+ incl r2
+Loop2:
+ leal 4(dst),dst
+ movl (src1),r1
+ sbbl x,r1
+ movl 4(src2),x
+ movl r1,-4(dst)
+ leal 4(src1),src1
+ leal 4(src2),src2
+ decl r2
+ jnz Loop2
+Lend2:
+ movl (src1),r1
+ sbbl x,r1
+ movl r1,(dst)
+
+ sbbl %eax,%eax
+ negl %eax
+
+ popl %ebp
+ popl %ebx
+ popl %esi
+ popl %edi
+ ret