nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2024-11-22 06:44:35 +00:00
Code Issues Packages Projects Releases Wiki Activity

Change bitwise operator to more easily keep data in vector registers

Browse Source
This commit is contained in:
Mark Rousskov 2021-05-04 11:53:57 -04:00
parent a5f164faad
commit 9d4c0944cb
1 changed files with 7 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
compiler/rustc_index/src/bit_set.rs
View File

@ -355,14 +355,18 @@ where
Op: Fn(Word, Word) -> Word, Op: Fn(Word, Word) -> Word,
{ {
assert_eq!(out_vec.len(), in_vec.len()); assert_eq!(out_vec.len(), in_vec.len());
let mut changed = false; let mut changed = 0;
for (out_elem, in_elem) in iter::zip(out_vec, in_vec) { for (out_elem, in_elem) in iter::zip(out_vec, in_vec) {
let old_val = *out_elem; let old_val = *out_elem;
let new_val = op(old_val, *in_elem); let new_val = op(old_val, *in_elem);
*out_elem = new_val; *out_elem = new_val;
changed |= old_val != new_val; // This is essentially equivalent to a != with changed being a bool, but
// in practice this code gets auto-vectorized by the compiler for most
// operators. Using != here causes us to generate quite poor code as the
// compiler tries to go back to a boolean on each loop iteration.
changed |= old_val ^ new_val;
} }
changed changed != 0
} }
const SPARSE_MAX: usize = 8; const SPARSE_MAX: usize = 8;