BigUint always use u64 as the internal machine unsigned integer #13880
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| #[inline] | ||
| pub fn from_uint(n: uint) -> (BigDigit, BigDigit) { | ||
| pub fn from_machineuint(n: MachineUint) -> (BigDigit, BigDigit) { |
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This is a public-facing method, so this has the possibility of breaking existing code.
Could you adjust the commit message according to our guidelines?
Why did this change from uint to MachineInt? If it's always u64, could this just be from_u64?
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I change the commit message to reflect that. The story is that it was not clear before if a uint is an index/len or if it is the machine representation used internally. That's why I used MachineUint to be clear.
I do not use directly u64 for future optimization. For example, I can imagine that when we have u128, MachineUint cat be u128 if the performances are better.
Finally, maybe the cleanest thing to do is to make BigDigit private because it looks like internal plumbing, not public API.
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Why is it called |
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@kballard as said upward, because maybe later, we will want to use |
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@TeXitoi I'm confused because it's |
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@kballard for you, |
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@TeXitoi I'm not particularly familiar with the |
This change allow a speedup of ~1.5 on shootout-pidigits on a i32 system. `DoubleBigDigit` is used to abstract the internal unsigned integer used in computation to simplity future architecture specialization. `BigDigit::from_uint` and `BigDigit::to_uint` become `BigDigit::from_doublebigdigit` and `BigDigit::to_doublebigdigit`. [breaking-change]
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@kballard just renamed |
This change allow a speedup of ~1.5 on shootout-pidigits on a i32 system. `MachineUint` is used to abstract the internal machine unsigned integer to simplity future architecture specialization.
Fixes rust-lang/rust-clippy#13744. A simple check to check if the type is an `Option` allows to improve the suggestion. changelog: Improve `needless_pass_by_value` suggestion
This change allow a speedup of ~1.5 on shootout-pidigits on a i32
system.
MachineUintis used to abstract the internal machineunsigned integer to simplity future architecture specialization.