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-rw-r--r--grub-core/lib/libgcrypt/mpi/i586/mpih-rshift.S228
1 files changed, 228 insertions, 0 deletions
diff --git a/grub-core/lib/libgcrypt/mpi/i586/mpih-rshift.S b/grub-core/lib/libgcrypt/mpi/i586/mpih-rshift.S
new file mode 100644
index 0000000..c661e3d
--- /dev/null
+++ b/grub-core/lib/libgcrypt/mpi/i586/mpih-rshift.S
@@ -0,0 +1,228 @@
+/* i80586 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
+ pushl %ebp
+
+ movl 20(%esp),%edi /* res_ptr */
+ movl 24(%esp),%esi /* s_ptr */
+ movl 28(%esp),%ebp /* size */
+ movl 32(%esp),%ecx /* cnt */
+
+/* We can use faster code for shift-by-1 under certain conditions. */
+ cmp $1,%ecx
+ jne Rnormal
+ leal 4(%edi),%eax
+ cmpl %esi,%eax
+ jnc Rspecial /* jump if res_ptr + 1 >= s_ptr */
+ leal (%edi,%ebp,4),%eax
+ cmpl %eax,%esi
+ jnc Rspecial /* jump if s_ptr >= res_ptr + size */
+
+Rnormal:
+ movl (%esi),%edx
+ addl $4,%esi
+ xorl %eax,%eax
+ shrdl %cl,%edx,%eax /* compute carry limb */
+ pushl %eax /* push carry limb onto stack */
+
+ decl %ebp
+ pushl %ebp
+ shrl $3,%ebp
+ jz Rend
+
+ movl (%edi),%eax /* fetch destination cache line */
+
+ ALIGN (2)
+Roop: movl 28(%edi),%eax /* fetch destination cache line */
+ movl %edx,%ebx
+
+ movl (%esi),%eax
+ movl 4(%esi),%edx
+ shrdl %cl,%eax,%ebx
+ shrdl %cl,%edx,%eax
+ movl %ebx,(%edi)
+ movl %eax,4(%edi)
+
+ movl 8(%esi),%ebx
+ movl 12(%esi),%eax
+ shrdl %cl,%ebx,%edx
+ shrdl %cl,%eax,%ebx
+ movl %edx,8(%edi)
+ movl %ebx,12(%edi)
+
+ movl 16(%esi),%edx
+ movl 20(%esi),%ebx
+ shrdl %cl,%edx,%eax
+ shrdl %cl,%ebx,%edx
+ movl %eax,16(%edi)
+ movl %edx,20(%edi)
+
+ movl 24(%esi),%eax
+ movl 28(%esi),%edx
+ shrdl %cl,%eax,%ebx
+ shrdl %cl,%edx,%eax
+ movl %ebx,24(%edi)
+ movl %eax,28(%edi)
+
+ addl $32,%esi
+ addl $32,%edi
+ decl %ebp
+ jnz Roop
+
+Rend: popl %ebp
+ andl $7,%ebp
+ jz Rend2
+Roop2: movl (%esi),%eax
+ shrdl %cl,%eax,%edx /* compute result limb */
+ movl %edx,(%edi)
+ movl %eax,%edx
+ addl $4,%esi
+ addl $4,%edi
+ decl %ebp
+ jnz Roop2
+
+Rend2: shrl %cl,%edx /* compute most significant limb */
+ movl %edx,(%edi) /* store it */
+
+ popl %eax /* pop carry limb */
+
+ popl %ebp
+ popl %ebx
+ popl %esi
+ popl %edi
+ ret
+
+/* We loop from least significant end of the arrays, which is only
+ permissable if the source and destination don't overlap, since the
+ function is documented to work for overlapping source and destination.
+*/
+
+Rspecial:
+ leal -4(%edi,%ebp,4),%edi
+ leal -4(%esi,%ebp,4),%esi
+
+ movl (%esi),%edx
+ subl $4,%esi
+
+ decl %ebp
+ pushl %ebp
+ shrl $3,%ebp
+
+ shrl $1,%edx
+ incl %ebp
+ decl %ebp
+ jz RLend
+
+ movl (%edi),%eax /* fetch destination cache line */
+
+ ALIGN (2)
+RLoop: movl -28(%edi),%eax /* fetch destination cache line */
+ movl %edx,%ebx
+
+ movl (%esi),%eax
+ movl -4(%esi),%edx
+ rcrl $1,%eax
+ movl %ebx,(%edi)
+ rcrl $1,%edx
+ movl %eax,-4(%edi)
+
+ movl -8(%esi),%ebx
+ movl -12(%esi),%eax
+ rcrl $1,%ebx
+ movl %edx,-8(%edi)
+ rcrl $1,%eax
+ movl %ebx,-12(%edi)
+
+ movl -16(%esi),%edx
+ movl -20(%esi),%ebx
+ rcrl $1,%edx
+ movl %eax,-16(%edi)
+ rcrl $1,%ebx
+ movl %edx,-20(%edi)
+
+ movl -24(%esi),%eax
+ movl -28(%esi),%edx
+ rcrl $1,%eax
+ movl %ebx,-24(%edi)
+ rcrl $1,%edx
+ movl %eax,-28(%edi)
+
+ leal -32(%esi),%esi /* use leal not to clobber carry */
+ leal -32(%edi),%edi
+ decl %ebp
+ jnz RLoop
+
+RLend: popl %ebp
+ sbbl %eax,%eax /* save carry in %eax */
+ andl $7,%ebp
+ jz RLend2
+ addl %eax,%eax /* restore carry from eax */
+RLoop2: movl %edx,%ebx
+ movl (%esi),%edx
+ rcrl $1,%edx
+ movl %ebx,(%edi)
+
+ leal -4(%esi),%esi /* use leal not to clobber carry */
+ leal -4(%edi),%edi
+ decl %ebp
+ jnz RLoop2
+
+ jmp RL1
+RLend2: addl %eax,%eax /* restore carry from eax */
+RL1: movl %edx,(%edi) /* store last limb */
+
+ movl $0,%eax
+ rcrl $1,%eax
+
+ popl %ebp
+ popl %ebx
+ popl %esi
+ popl %edi
+ ret
+