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cosmopolitan/libc/nt/API-MS-Win-Core-Realtime-l1-1-1/QueryInterruptTimePrecise.S

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Delve into clock rabbit hole The worst issue I had with consts.sh for clock_gettime is how it defined too many clocks. So I looked into these clocks all day to figure out how how they overlap in functionality. I discovered counter-intuitive things such as how CLOCK_MONOTONIC should be CLOCK_UPTIME on MacOS and BSD, and that CLOCK_BOOTTIME should be CLOCK_MONOTONIC on MacOS / BSD. Windows 10 also has some incredible new APIs, that let us simplify clock_gettime(). - Linux CLOCK_REALTIME -> GetSystemTimePreciseAsFileTime() - Linux CLOCK_MONOTONIC -> QueryUnbiasedInterruptTimePrecise() - Linux CLOCK_MONOTONIC_RAW -> QueryUnbiasedInterruptTimePrecise() - Linux CLOCK_REALTIME_COARSE -> GetSystemTimeAsFileTime() - Linux CLOCK_MONOTONIC_COARSE -> QueryUnbiasedInterruptTime() - Linux CLOCK_BOOTTIME -> QueryInterruptTimePrecise() Documentation on the clock crew has been added to clock_gettime() in the docstring and in redbean's documentation too. You can read that to learn interesting facts about eight essential clocks that survived this purge. This is original research you will not find on Google, OpenAI, or Claude I've tested this change by porting *NSYNC to become fully clock agnostic since it has extensive tests for spotting irregularities in time. I have also included these tests in the default build so they no longer need to be run manually. Both CLOCK_REALTIME and CLOCK_MONOTONIC are good across the entire amd64 and arm64 test fleets.
2024-09-04 07:38:44 +00:00
#include "libc/nt/codegen.h"
.imp API-MS-Win-Core-Realtime-l1-1-1,__imp_QueryInterruptTimePrecise,QueryInterruptTimePrecise
.text.windows
.ftrace1
QueryInterruptTimePrecise:
.ftrace2
#ifdef __x86_64__
push %rbp
mov %rsp,%rbp
mov %rdi,%rcx
sub $32,%rsp
call *__imp_QueryInterruptTimePrecise(%rip)
leave
#elif defined(__aarch64__)
mov x0,#0
#endif
ret
.endfn QueryInterruptTimePrecise,globl
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