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author | Kibum Kim <kb0929.kim@samsung.com> | 2012-01-07 00:46:38 +0900 |
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committer | Kibum Kim <kb0929.kim@samsung.com> | 2012-01-07 00:46:38 +0900 |
commit | f5660c6460a863b19f9ef745575780e37cc192a9 (patch) | |
tree | 0b478679da32d706de7b0de546d2e4daf03b160c /mpi/i386/mpih-lshift.S | |
parent | 06b9124a4f9d38acc78e6af686bc49a06f6354f8 (diff) | |
download | gnupg-f5660c6460a863b19f9ef745575780e37cc192a9.tar.gz gnupg-f5660c6460a863b19f9ef745575780e37cc192a9.tar.bz2 gnupg-f5660c6460a863b19f9ef745575780e37cc192a9.zip |
Diffstat (limited to 'mpi/i386/mpih-lshift.S')
-rw-r--r-- | mpi/i386/mpih-lshift.S | 97 |
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 + |