align.wyv

// align.wyv — a layout contract the optimizer can use.
//
// @align(64) promises 64-byte (cache-line) alignment on each pointer.
// It lowers to LLVM's `align` parameter attribute, so the vectorizer
// emits aligned vector memory ops (vmovaps) instead of unaligned ones
// (vmovups) — and skips the scalar prologue that peels iterations to
// reach an aligned boundary. The promise is the caller's to keep; pass a
// misaligned pointer and you get undefined behavior, exactly as the
// contract states.

@interface Align

@effect(reads(x), writes(dst))
@vectorize(require, width: 8)
+ (void)scale:(float)a
            x:(@noalias @align(64) const float *)x
          dst:(@noalias @align(64) float *)dst
        count:(usize)n;

@end

@implementation Align

+ (void)scale:(float)a
            x:(@noalias @align(64) const float *)x
          dst:(@noalias @align(64) float *)dst
        count:(usize)n
{
    for (usize i = 0; i < n; i++) {
        dst[i] = a * x[i];
    }
}

@end