tiny.simd.mulHigh

1pub fn mulHigh(comptime D: type, a: D.Vector, b: D.Vector) D.Vector {2    requireInteger(D.Lane, "mulHigh");3    const bits = @bitSizeOf(D.Lane);4    const WideSigned = @Int(.signed, bits * 2);5    const WideUnsigned = @Int(.unsigned, bits * 2);6    const Unsigned = @Int(.unsigned, bits);7    var result: D.Vector = undefined;8    inline for (0..D.lane_count) |index| {9        const high: Unsigned = if (@typeInfo(D.Lane).int.signedness == .signed) blk: {10            const product = @as(WideSigned, a[index]) * @as(WideSigned, b[index]);11            const product_bits: WideUnsigned = @bitCast(product);12            break :blk @truncate(product_bits >> bits);13        } else blk: {14            const product = @as(WideUnsigned, a[index]) * @as(WideUnsigned, b[index]);15            break :blk @truncate(product >> bits);16        };17        result[index] = @bitCast(high);18    }19    return result;20}

1pub const mulHigh = multiply.mulHigh;