diff options
| -rw-r--r-- | library/core/src/slice/mod.rs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs index c7dd000f71f..bc3f02efdda 100644 --- a/library/core/src/slice/mod.rs +++ b/library/core/src/slice/mod.rs @@ -2163,6 +2163,10 @@ impl<T> [T] { // - `mid >= 0` // - `mid < size`: `mid` is limited by `[left; right)` bound. let cmp = f(unsafe { self.get_unchecked(mid) }); + + // The reason why we use if/else control flow rather than match + // is because match reorders comparison operations, which is perf sensitive. + // This is x86 asm for u8: https://rust.godbolt.org/z/8Y8Pra. if cmp == Less { left = mid + 1; } else if cmp == Greater { |