bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Cut code size for feature hashing

Browse source 
This locally cuts ~32 kB of .text instructions.
This commit is contained in:
Mark Rousskov 2023-11-26 22:32:41 -05:00
parent 1bcbb7c93b
commit 1487bd6a17
2 changed files with 14 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

12
compiler/rustc_feature/src/unstable.rs
View file

@ -50,6 +50,8 @@ macro_rules! declare_features {
}),+
];
const NUM_FEATURES: usize = UNSTABLE_FEATURES.len();
/// A set of features to be used by later passes.
#[derive(Clone, Default, Debug)]
pub struct Features {
@ -82,8 +84,14 @@ macro_rules! declare_features {
self.declared_features.insert(symbol);
}
pub fn walk_feature_fields(&self, mut f: impl FnMut(&str, bool)) {
$(f(stringify!($feature), self.$feature);)+
/// This is intended for hashing the set of active features.
///
/// The expectation is that this produces much smaller code than other alternatives.
///
/// Note that the total feature count is pretty small, so this is not a huge array.
#[inline]
pub fn all_features(&self) -> [u8; NUM_FEATURES] {
[$(self.$feature as u8),+]
}
/// Is the given feature explicitly declared, i.e. named in a