bendns' repos / aoc
heh
add a lil simd
Browse Source
bendn 2024-12-25
parent 9d93ea3 · commit fcca239
Diffstat
-rw-r--r--src/main.rs22
1 files changed, 15 insertions, 7 deletions
diff --git a/src/main.rs b/src/main.rs
index 887bb8e..66ca4b3 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -35,6 +35,8 @@
)]
extern crate test;
pub mod util;
+use std::simd::prelude::*;
+
pub use util::prelude::*;
const SIZE: usize = 5;
const H: usize = 7;
@@ -47,13 +49,19 @@ pub unsafe fn p1(x: &str) -> impl Display {
let mut locks = [0u64; 250];
let mut li = 0;
for _ in 0..500 {
- let mut acc = 0;
- for y in 0..H {
- for x in 0..SIZE {
- acc <<= 1;
- acc |= (i.add(y * 6 + x).read() == b'#') as u64
- }
- }
+ let simd = u8x64::load_or_default(std::slice::from_raw_parts(i, 42));
+ #[rustfmt::skip]
+ let simd = simd_swizzle!(
+ simd,
+ [0, 1, 2, 3, 4, // 5
+ 6, 7, 8, 9, 10, // 11
+ 12, 13, 14, 15, 16, // 17
+ 18, 19, 20, 21, 22, // 23
+ 24, 25, 26, 27, 28, // 29
+ 30, 31, 32, 33, 34,
+ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
+ );
+ let acc = simd.simd_eq(Simd::splat(b'#')).to_bitmask();
i = i.add(6 * 7 + 1);
if acc & 1 == 0 {
C! { keys[ki] = acc };