SIMD benchmark

[Simen Kjærås]

On Mon, 16 Jan 2012 23:06:12 +0100, Manu <turkeyman at gmail.com> wrote:

> On 17 January 2012 00:03, Walter Bright <newshound2 at digitalmars.com>  
> wrote:
>
>> On 1/16/2012 1:54 PM, Manu wrote:
>>
>>>    Unfortunately, if the function was this:
>>>
>>>    void foo(int[] a, int[] b, int[] c) {
>>>
>>>      for (int i=0; i<256; i++)
>>>        a[i] = b[i] + c[i];
>>>    }
>>>
>>>    Then it can't vectorize due to aliasing.
>>>
>>>
>>> This is why D needs a __restrict attribute! ;)
>>>
>>
>> That's why D has:
>>
>>   a[] = b[] + c[];
>>
>> because the language requires the arrays to be distinct.
>>
>
> Surely it would be possible for them to be overlapping slices?

If they are, that's your fault and your problem.

"The lvalue slice and any rvalue slices must not overlap."