It all back in the 90’s where Intel came up with the dashing MMX technology. AMD wasn’t so late to respond with its new 3DNow! instruction set. That if you ask me, was much less popular and less used. But the good thing about 3DNow! is that it handled floating points rather than integers. And then came SSE instruction set, and the world got better and nowadays compilers even use it up to SSE2 while knowing it will be there when the code runs for 99% today. However, they still make a SSE test to be sure they can use it, I believe this check will always stay in code for assurance anyway, can’t harm, you know.
Now almost 10 years later, we see another split in technologies, Intel came up with SSE4, I already talked about it in an earlier post, which contained really valuable instructions. And then, guess what? AMD added several instruction on top of Intel’s.
In August 07 AMD announced a new set: SSE5. Aren’t we sick off SSE anymore??? Anyway, in April this year, Intel announced in response a new AVX instruction set (Advanced Vector Extensions).
This doesn’t go anywhere. Every company in its turn announces a new instruction set. The first company doesn’t support the other’s and vice versa. This is just going wrong and it’s our nightmare. Basically, most developers should not care anyway, they don’t use these sets, and they (partly) are not out officially (means you can’t use it as for now). Therefore, the game matters for compiler developers and those who write the tools that mess with machine code, etc. Probably many codecs and crypto algos will use it too directly if it exists on the processor they get to run on…
The thing is, I decided to take a side, and to stick only to AVX, and therefore I won’t support SSE5 in diStorm. If anyone from the community is gonna help with that, I will gladly accept it, don’t get me wrong. Since I don’t have much time for it anyway, and I hate this mess up, I will stick to Intel. I don’t know if it’s a good or bad news for diStorm, but as the only owner and the way I see it, I gotta do something against this lack of standard thing. Everything has standards today, why can’t the damned x86 have one as well?
I’m not the only one who speaks about this, Agner Fog has also talked about it here. The difference is that I can make my own small change.
What do you think should happen with this issue??? Who’s right, Intel or AMD? Should developers code twice now for each instruction set?
arrrrgh so many questions
And the results are:
1 – one more blog article
2 – missing instructions in diStrom
Was it worth it? ;-)
Now you know what I think.
And what’s diStorm’s future gonna be :)
The answer is they’re both wrong. But it doesn’t matter, in a few years the x86 will be replaced by quantum computing anyway ;)
[…] Anyhow, I had some free time, of course, I am on a vacation, sort of, after all. And I accidentally reached some amazing blog that I couldnt stopped reading for a few days. Meet NO EXECUTE! If you are low level freaks like me, you will really like it too, although Darek begins with hardware stuff, which will fill some gaps for most people I believe, he talks about virtualizations and emulators (his obsession), and I just read it like some fantasies book, eager to get already to the next chapter everytime. I learnt tons of stuff there, and I really like to see that even today some few people still measure and check optimizations in cycles per instructions rather than seconds or MS. One of the stuff I really liked there was a trick he pulled when the guest OS runs on little endian, for instance, and the host OS runs on big endian. Thus every access to memory has to be swapped when the size of the access is more than 2 bytes, of course. Therefore, in order to eliminate the byte swaps, which is expensive, he kinda turned all the memory of the guest OS upside down, and therefore the endianity changed as well. Now it might sound as a simple matter, but this is awesome, and the way he describes it, you can really feel the excitment behind the invention… He also talks about how lame Intel and AMD are to come up with new instruction sets every Monday, which I already mentioned also in the past. […]