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ecc6e95ed4
All derive ops currently use match-destructuring to access fields. This is reasonable for enums, but sub-optimal for structs. E.g.: ``` fn eq(&self, other: &Point) -> bool { match *other { Self { x: ref __self_1_0, y: ref __self_1_1 } => match *self { Self { x: ref __self_0_0, y: ref __self_0_1 } => (*__self_0_0) == (*__self_1_0) && (*__self_0_1) == (*__self_1_1), }, } } ``` This commit changes derive ops on structs to use field access instead, e.g.: ``` fn eq(&self, other: &Point) -> bool { self.x == other.x && self.y == other.y } ``` This is faster to compile, results in smaller binaries, and is simpler to generate. Unfortunately, we have to keep the old pattern generating code around for `repr(packed)` structs because something like `&self.x` (which doesn't show up in `PartialEq` ops, but does show up in `Debug` and `Hash` ops) isn't allowed. But this commit at least changes those cases to use let-destructuring instead of match-destructuring, e.g.: ``` fn hash<__H: ::core:#️⃣:Hasher>(&self, state: &mut __H) -> () { { let Self(ref __self_0_0) = *self; { ::core:#️⃣:Hash::hash(&(*__self_0_0), state) } } } ``` There are some unnecessary blocks remaining in the generated code, but I will fix them in a follow-up PR. |
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