/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│ │vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi│ ╞══════════════════════════════════════════════════════════════════════════════╡ │ Copyright 2020 Justine Alexandra Roberts Tunney │ │ │ │ This program 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; version 2 of the License. │ │ │ │ This program 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 │ ╚─────────────────────────────────────────────────────────────────────────────*/ #include "libc/macros.h" / Sets memory to zero w/ accompanying non-optimizing macro. / / This is intended for security-conscious applications. This / implementation also hoses every register the abi allows. A / concomitant prototype (str.h) countermands compiler magic. / / @param rdi is dest / @param rsi is the number of bytes to set explicit_bzero: .leafprologue mov %rsi,%rcx xor %eax,%eax rep stosb xor %edx,%edx xor %edi,%edi xor %esi,%esi xor %r8,%r8 xor %r9,%r9 xor %r10,%r10 xor %r11,%r11 pxor %xmm0,%xmm0 pxor %xmm1,%xmm1 pxor %xmm2,%xmm2 pxor %xmm3,%xmm3 pxor %xmm4,%xmm4 pxor %xmm5,%xmm5 .leafepilogue .endfn explicit_bzero,globl .source __FILE__