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les: rework arm64's undefined workaround #21994

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Merged
merged 1 commit into from
Dec 11, 2020
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les: rework arm64's undefined workaround #21994

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12 changes: 8 additions & 4 deletions les/utils/expiredvalue.go
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Original file line number Diff line number Diff line change
Expand Up @@ -86,11 +86,15 @@ func (e *ExpiredValue) Add(amount int64, logOffset Fixed64) int64 {
e.Exp = integer
}
if base >= 0 || uint64(-base) <= e.Base {
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@holiman holiman Dec 10, 2020 •
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simpler:

	if base >= 0{
		e.Base += uint64(base)
	}else if uint64(-base) <= e.base{
		// The conversion from negative float64 to
		// uint64 is undefined in golang, and doesn't
		// work with ARMv8. More details at:
		// https://github.com/golang/go/issues/43047
		e.Base -= uint64(-base)
	}
	return amount

... ?

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Ah nevermind...

// This is a temporary fix to circumvent a golang
// uint conversion issue on arm64, which needs to
// be investigated further. More details at:
// The conversion from negative float64 to
// uint64 is undefined in golang, and doesn't
// work with ARMv8. More details at:
// https://github.com/golang/go/issues/43047
e.Base += uint64(int64(base))
if base >= 0 {
e.Base += uint64(base)
} else {
e.Base -= uint64(-base)
}
return amount
}
net := int64(-float64(e.Base) / factor)
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