adaac6b166
Rewrite MemDecoder around pointers not a slice This is basically https://github.com/rust-lang/rust/pull/109910 but I'm being a lot more aggressive. The pointer-based structure means that it makes a lot more sense to absorb more complexity into `MemDecoder`, most of the diff is just complexity moving from one place to another. The primary argument for this structure is that we only incur a single bounds check when doing multi-byte reads from a `MemDecoder`. With the slice-based implementation we need to do those with `data[position..position + len]` , which needs to account for `position + len` wrapping. It would be possible to dodge the first bounds check if we stored a slice that starts at `position`, but that would require updating the pointer and length on every read. This PR also embeds the failure path in a separate function, which means that this PR should subsume all the perf wins observed in https://github.com/rust-lang/rust/pull/109867. |
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| Cargo.toml | ||
| messages.ftl | ||
| README.md | ||
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