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@@ -0,0 +1,28 @@
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+//+private
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+//+build windows
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+package time
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+
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+import win32 "core:sys/windows"
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+
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+_get_tsc_frequency :: proc "contextless" () -> u64 {
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+ @(static) frequency : u64 = 0
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+ if frequency > 0 {
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+ return frequency
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+ }
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+
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+ qpc_begin: win32.LARGE_INTEGER
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+ win32.QueryPerformanceCounter(&qpc_begin)
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+ tsc_begin := intrinsics.read_cycle_counter()
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+
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+ win32.Sleep(2)
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+
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+ qpc_end: win32.LARGE_INTEGER
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+ win32.QueryPerformanceCounter(&qpc_end)
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+ tsc_end := intrinsics.read_cycle_counter()
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+
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+ qpc_frequency: win32.LARGE_INTEGER
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+ win32.QueryPerformanceFrequency(&qpc_frequency)
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+
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+ frequency = ((tsc_end - tsc_begin) * qpc_frequency) / (qpc_end - qpc_begin)
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+ return frequency
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+}
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