std.random.unpredictableSeed: on x86/x86-64 try using RDRAND when there is no arc4random #7436
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Thanks for your pull request, @n8sh! Bugzilla references
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n8sh
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Apr 7, 2020
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| // If we don't have arc4random and we don't have RDSEED fall back to this. | ||
| private ulong fallbackSeed() @nogc nothrow | ||
| { |
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This code was moved out of unpredictableSeed into its own function.
thewilsonator
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Apr 7, 2020
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It might make sense to use RDRAND instead since it suffers less from contention. RDRAND is similar to macOS arc4random: it's an AES-based CPRNG that periodically reseeds itself. EDIT: RDRAND is also available on more machines than RDSEED. |
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…ng RDRAND when there is no arc4random This code works in both DMD and LDC because LDC version 1.20.0 added support for data directives in DMD-style inline asm.
n8sh
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72h no objection -> merge
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This enhancement is now possible (without being DMD-only) because LDC version 1.20.0 added support for data directives in DMD-style inline asm.