| /* AMD64 (x86_64) sub_n -- Subtract two limb vectors of the same length > 0 and store |
| * sum in a third limb vector. |
| * |
| * Copyright (C) 1992, 1994, 1995, 1998, |
| * 2001, 2002, 2006 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_sub_n( mpi_ptr_t res_ptr, rdi |
| * mpi_ptr_t s1_ptr, rsi |
| * mpi_ptr_t s2_ptr, rdx |
| * mpi_size_t size) rcx |
| */ |
| .text |
| .globl C_SYMBOL_NAME(_gcry_mpih_sub_n) |
| C_SYMBOL_NAME(_gcry_mpih_sub_n:) |
| leaq (%rsi,%rcx,8), %rsi |
| leaq (%rdi,%rcx,8), %rdi |
| leaq (%rdx,%rcx,8), %rdx |
| negq %rcx |
| xorl %eax, %eax /* clear cy */ |
| |
| ALIGN(4) /* minimal alignment for claimed speed */ |
| .Loop: movq (%rsi,%rcx,8), %rax |
| movq (%rdx,%rcx,8), %r10 |
| sbbq %r10, %rax |
| movq %rax, (%rdi,%rcx,8) |
| incq %rcx |
| jne .Loop |
| |
| movq %rcx, %rax /* zero %rax */ |
| adcq %rax, %rax |
| ret |
