1 files changed, 97 insertions, 0 deletions
diff --git a/mpi/i386/mpih-lshift.S b/mpi/i386/mpih-lshift.S
new file mode 100644
index 0000000..9233824
--- /dev/null
+++ b/mpi/i386/mpih-lshift.S
@@ -0,0 +1,97 @@
+/* i80386   lshift
+ *      Copyright (C) 1992, 1994, 1998,
+ *                    2001 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
+ *
+ * Note: This code is heavily based on the GNU MP Library.
+ *	 Actually it's the same code with only minor changes in the
+ *	 way the data is stored; this is to support the abstraction
+ *	 of an optional secure memory allocation which may be used
+ *	 to avoid revealing of sensitive data due to paging etc.
+ *	 The GNU MP Library itself is published under the LGPL;
+ *	 however I decided to publish this code under the plain GPL.
+ */
+
+
+#include "sysdep.h"
+#include "asm-syntax.h"
+
+
+/*******************
+ * mpi_limb_t
+ * mpihelp_lshift( mpi_ptr_t wp,	(sp + 4)
+ *		   mpi_ptr_t up,	(sp + 8)
+ *		   mpi_size_t usize,	(sp + 12)
+ *		   unsigned cnt)	(sp + 16)
+ */
+
+.text
+	ALIGN (3)
+	.globl C_SYMBOL_NAME(mpihelp_lshift)
+C_SYMBOL_NAME(mpihelp_lshift:)
+	pushl	%edi
+	pushl	%esi
+	pushl	%ebx
+
+	movl	16(%esp),%edi		/* res_ptr */
+	movl	20(%esp),%esi		/* s_ptr */
+	movl	24(%esp),%edx		/* size */
+	movl	28(%esp),%ecx		/* cnt */
+
+	subl	$4,%esi 		/* adjust s_ptr */
+
+	movl	(%esi,%edx,4),%ebx	/* read most significant limb */
+	xorl	%eax,%eax
+	shldl	%ebx,%eax		/* compute carry limb */
+	decl	%edx
+	jz	Lend
+	pushl	%eax			/* push carry limb onto stack */
+	testb	$1,%dl
+	jnz	L1			/* enter loop in the middle */
+	movl	%ebx,%eax
+
+	ALIGN (3)
+Loop:	movl	(%esi,%edx,4),%ebx	/* load next lower limb */
+	shldl	%ebx,%eax		/* compute result limb */
+	movl	%eax,(%edi,%edx,4)	/* store it */
+	decl	%edx
+L1:	movl	(%esi,%edx,4),%eax
+	shldl	%eax,%ebx
+	movl	%ebx,(%edi,%edx,4)
+	decl	%edx
+	jnz	Loop
+
+	shll	%cl,%eax		/* compute least significant limb */
+	movl	%eax,(%edi)		/* store it */
+
+	popl	%eax			/* pop carry limb */
+
+	popl	%ebx
+	popl	%esi
+	popl	%edi
+	ret
+
+Lend:	shll	%cl,%ebx		/* compute least significant limb */
+	movl	%ebx,(%edi)		/* store it */
+
+	popl	%ebx
+	popl	%esi
+	popl	%edi
+	ret
+