Some slightly performance & style updates

ParkMyCar / compact_str

A memory efficient string type that can store up to 24* bytes on the stack

MIT License

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Some slightly performance & style updates #370

Open yhx-12243 opened 3 months ago

yhx-12243 commented 3 months ago

In the function fn as_bytes in impl CompactString, there is an redundant slicing (with a self.len() call) which is unnecessary after the update c95edd5.
This crate has documented that for 64-bit architectures the capacity will be always inlined. So the logic of is_heap can be replaced with directly returning false to reduce some code generation.

yhx-12243 commented 3 months ago

It seems that the test needs to be changed, because it's probably that the compiler optimized out the whole test and did not allocate memory at all.

See https://rust.godbolt.org/z/qc349PrGv for a shorter analogue.

yhx-12243 commented 3 months ago

May be we should wrap this test in a something like core::hint::black_box, or maybe do other things to make sure the compiler will not optimize out the "unused" allocation of long string.