diff options
| author | Nicholas Nethercote <n.nethercote@gmail.com> | 2022-03-23 13:09:55 +1100 |
|---|---|---|
| committer | Nicholas Nethercote <n.nethercote@gmail.com> | 2022-03-25 12:35:56 +1100 |
| commit | cad5f1e7742e46ce16dc54d38516301e3ae72a9e (patch) | |
| tree | 279a70140c079ddcb005abd62c48a0526ddeafdc | |
| parent | 6817442ec7d9f29abfb080314f3c45ff5e3e633a (diff) | |
| download | rust-cad5f1e7742e46ce16dc54d38516301e3ae72a9e.tar.gz rust-cad5f1e7742e46ce16dc54d38516301e3ae72a9e.zip | |
Shrink `NamedMatchVec` to one inline element.
This counters the `NamedMatchVec` size increase from the previous commit, leaving `NamedMatchVec` smaller than before.
| -rw-r--r-- | compiler/rustc_expand/src/mbe/macro_parser.rs | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/compiler/rustc_expand/src/mbe/macro_parser.rs b/compiler/rustc_expand/src/mbe/macro_parser.rs index f2090899e99..63c43cc8a33 100644 --- a/compiler/rustc_expand/src/mbe/macro_parser.rs +++ b/compiler/rustc_expand/src/mbe/macro_parser.rs @@ -101,11 +101,14 @@ struct MatcherTtFrame<'tt> { idx: usize, } -type NamedMatchVec = SmallVec<[NamedMatch; 4]>; +// One element is enough to cover 95-99% of vectors for most benchmarks. Also, +// vectors longer than one frequently have many elements, not just two or +// three. +type NamedMatchVec = SmallVec<[NamedMatch; 1]>; // This type is used a lot. Make sure it doesn't unintentionally get bigger. #[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))] -rustc_data_structures::static_assert_size!(NamedMatchVec, 168); +rustc_data_structures::static_assert_size!(NamedMatchVec, 48); /// Represents a single "position" (aka "matcher position", aka "item"), as /// described in the module documentation. |