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-rw-r--r--grub-core/lib/libgcrypt/mpi/i386/mpih-rshift.S97
1 files changed, 97 insertions, 0 deletions
diff --git a/grub-core/lib/libgcrypt/mpi/i386/mpih-rshift.S b/grub-core/lib/libgcrypt/mpi/i386/mpih-rshift.S
new file mode 100644
index 0000000..2920e55
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+++ b/grub-core/lib/libgcrypt/mpi/i386/mpih-rshift.S
@@ -0,0 +1,97 @@
+/* i80386 rshift
+ *
+ * Copyright (C) 1992, 1994, 1998,
+ * 2001, 2002 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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.
+ */
+
+
+#include "sysdep.h"
+#include "asm-syntax.h"
+
+
+/*******************
+ * mpi_limb_t
+ * _gcry_mpih_rshift( 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(_gcry_mpih_rshift)
+C_SYMBOL_NAME(_gcry_mpih_rshift:)
+ pushl %edi
+ pushl %esi
+ pushl %ebx
+
+ movl 16(%esp),%edi /* wp */
+ movl 20(%esp),%esi /* up */
+ movl 24(%esp),%edx /* usize */
+ movl 28(%esp),%ecx /* cnt */
+
+ leal -4(%edi,%edx,4),%edi
+ leal (%esi,%edx,4),%esi
+ negl %edx
+
+ movl (%esi,%edx,4),%ebx /* read least significant limb */
+ xorl %eax,%eax
+ shrdl %cl,%ebx,%eax /* compute carry limb */
+ incl %edx
+ jz Lend2
+ pushl %eax /* push carry limb onto stack */
+ testb $1,%dl
+ jnz L2 /* enter loop in the middle */
+ movl %ebx,%eax
+
+ ALIGN (3)
+Loop2: movl (%esi,%edx,4),%ebx /* load next higher limb */
+ shrdl %cl,%ebx,%eax /* compute result limb */
+ movl %eax,(%edi,%edx,4) /* store it */
+ incl %edx
+L2: movl (%esi,%edx,4),%eax
+ shrdl %cl,%eax,%ebx
+ movl %ebx,(%edi,%edx,4)
+ incl %edx
+ jnz Loop2
+
+ shrl %cl,%eax /* compute most significant limb */
+ movl %eax,(%edi) /* store it */
+
+ popl %eax /* pop carry limb */
+
+ popl %ebx
+ popl %esi
+ popl %edi
+ ret
+
+Lend2: shrl %cl,%ebx /* compute most significant limb */
+ movl %ebx,(%edi) /* store it */
+
+ popl %ebx
+ popl %esi
+ popl %edi
+ ret
+