cosmopolitan/libc/calls/gettimeofday-sysv.S

55 lines
2.6 KiB
ArmAsm

/*-*- 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/dce.h"
#include "libc/macros.h"
/ Returns system wall time in microseconds.
/
/ @param rdi points to timeval that receives result
/ @param rsi receives UTC timezone if non-NULL
/ @return always zero
/ @see clock_gettime() for nanosecond precision
/ @see strftime() for string formatting
gettimeofday$sysv:
push %rbp
mov %rsp,%rbp
.profilable
test %rsi,%rsi
jz 1f
push $0
pop (%rsi)
1: xor %esi,%esi # no one zones this way.
xor %edx,%edx # i64*mach_absolute_time
call __gettimeofday$sysv
#if SupportsXnu()
testb IsXnu() # XNU might do %rax:%rdx
jz 1f
test %rdi,%rdi
jz 1f
test %rax,%rax
jz 1f
mov %rax,(%rdi)
mov %rdx,8(%rdi)
#endif
1: xor %eax,%eax # nevar fail
pop %rbp
ret
.endfn gettimeofday$sysv,globl,hidden