diff options
Diffstat (limited to 'vendor/github.com/tetratelabs/wazero/internal/platform/time_windows.go')
-rw-r--r-- | vendor/github.com/tetratelabs/wazero/internal/platform/time_windows.go | 40 |
1 files changed, 0 insertions, 40 deletions
diff --git a/vendor/github.com/tetratelabs/wazero/internal/platform/time_windows.go b/vendor/github.com/tetratelabs/wazero/internal/platform/time_windows.go deleted file mode 100644 index 58731fc8e..000000000 --- a/vendor/github.com/tetratelabs/wazero/internal/platform/time_windows.go +++ /dev/null @@ -1,40 +0,0 @@ -//go:build windows - -package platform - -import ( - "math/bits" - "time" - "unsafe" -) - -var ( - _QueryPerformanceCounter = kernel32.NewProc("QueryPerformanceCounter") - _QueryPerformanceFrequency = kernel32.NewProc("QueryPerformanceFrequency") -) - -var qpcfreq uint64 - -func init() { - _, _, _ = _QueryPerformanceFrequency.Call(uintptr(unsafe.Pointer(&qpcfreq))) -} - -// On Windows, time.Time handled in time package cannot have the nanosecond precision. -// The reason is that by default, it doesn't use QueryPerformanceCounter[1], but instead, use "interrupt time" -// which doesn't support nanoseconds precision (though it is a monotonic) [2, 3, 4, 5]. -// -// [1] https://learn.microsoft.com/en-us/windows/win32/api/profileapi/nf-profileapi-queryperformancecounter -// [2] https://github.com/golang/go/blob/0cd309e12818f988693bf8e4d9f1453331dcf9f2/src/runtime/sys_windows_amd64.s#L297-L298 -// [3] https://github.com/golang/go/blob/0cd309e12818f988693bf8e4d9f1453331dcf9f2/src/runtime/os_windows.go#L549-L551 -// [4] https://github.com/golang/go/blob/master/src/runtime/time_windows.h#L7-L13 -// [5] http://web.archive.org/web/20210411000829/https://wrkhpi.wordpress.com/2007/08/09/getting-os-information-the-kuser_shared_data-structure/ -// -// Therefore, on Windows, we directly invoke the syscall for QPC instead of time.Now or runtime.nanotime. -// See https://github.com/golang/go/issues/31160 for example. -func nanotime() int64 { - var counter uint64 - _, _, _ = _QueryPerformanceCounter.Call(uintptr(unsafe.Pointer(&counter))) - hi, lo := bits.Mul64(counter, uint64(time.Second)) - nanos, _ := bits.Div64(hi, lo, qpcfreq) - return int64(nanos) -} |