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2b74de3ed9
Change-Id: I37706ff0a3486827c5b072c95ad890ea87ede847 Reviewed-on: https://go-review.googlesource.com/28210 Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
27 lines
855 B
Go
27 lines
855 B
Go
// Copyright 2015 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package runtime
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var randomNumber uint32
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func archauxv(tag, val uintptr) {
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switch tag {
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case _AT_RANDOM:
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// sysargs filled in startupRandomData, but that
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// pointer may not be word aligned, so we must treat
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// it as a byte array.
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randomNumber = uint32(startupRandomData[4]) | uint32(startupRandomData[5])<<8 |
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uint32(startupRandomData[6])<<16 | uint32(startupRandomData[7])<<24
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}
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}
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//go:nosplit
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func cputicks() int64 {
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// Currently cputicks() is used in blocking profiler and to seed fastrand().
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// nanotime() is a poor approximation of CPU ticks that is enough for the profiler.
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// randomNumber provides better seeding of fastrand.
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return nanotime() + int64(randomNumber)
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}
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