cosmopolitan/libc/calls/gettimeofday-sysv.S

54 lines
2.5 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
Permission to use, copy, modify, and/or distribute this software for
any purpose with or without fee is hereby granted, provided that the
above copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/
#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