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Исправление hateyoufeel, (текущая версия) :

во многом из-за сложности создания ПО и инструментария для VLIW

Интересно, касается конкретно IA-64 или вообще в целом любого процессора с такой архитектурой?

Любого. VLIW не работает для процессоров общего назначения. Доказано итаником и еблрусом.

Тыц:

За ссылки на швабр прошу прощения.

В принципе, лучше всего ситуацию с итаником (это касается елборуса тоже, потому что он страдает от тех же проблем) описал Торовалтос:

IOW, I think Intel could possibly have saved Itanium had they been willing to admit this, and just treated Itanium as a strange RISC chip with an odd instruction grouping encoding, and make an aggressively OoO implementation. It would still have been a bad architecture design, but that’s nothing new: Intel made x86 work just fine despite all its problems.

I don’t think the odd encoding would have been fatal. It’s still a lot easier to parse than x86 ever was. The crazy register rotation/stack is nasty, but I think you could have mostly ignored it and tracked the rotation in the front end and handled it in the rename logic. Intel does more complex things with the x86 stack engine. Again, stupid design, but «solvable».

But if you can admit to yourself that OoO is just a good idea, then pretty much all of the things Itanium did were simply wrongheaded and stupid. They weren’t necessarily fatal, but they sure weren’t great ideas.

What was fatal was not recognizing that OoO is a requirement. If you cannot admit to yourself that OoO is what you should do, then the problem is squarely in your end, and I don’t know what to say.

Ссылка: https://www.realworldtech.com/forum/?threadid=193189&curpostid=193515%5C

Исправление hateyoufeel, :

во многом из-за сложности создания ПО и инструментария для VLIW

Интересно, касается конкретно IA-64 или вообще в целом любого процессора с такой архитектурой?

Любого. VLIW не работает для процессоров общего назначения. Доказано итаником и еблрусом.

Тыц:

За ссылки на швабр прошу прощения.

В принципе, лучше всего ситуацию с итаником (это касается елборуса тоже) описал Торовалтос:

IOW, I think Intel could possibly have saved Itanium had they been willing to admit this, and just treated Itanium as a strange RISC chip with an odd instruction grouping encoding, and make an aggressively OoO implementation. It would still have been a bad architecture design, but that’s nothing new: Intel made x86 work just fine despite all its problems.

I don’t think the odd encoding would have been fatal. It’s still a lot easier to parse than x86 ever was. The crazy register rotation/stack is nasty, but I think you could have mostly ignored it and tracked the rotation in the front end and handled it in the rename logic. Intel does more complex things with the x86 stack engine. Again, stupid design, but «solvable».

But if you can admit to yourself that OoO is just a good idea, then pretty much all of the things Itanium did were simply wrongheaded and stupid. They weren’t necessarily fatal, but they sure weren’t great ideas.

What was fatal was not recognizing that OoO is a requirement. If you cannot admit to yourself that OoO is what you should do, then the problem is squarely in your end, and I don’t know what to say.

Ссылка: https://www.realworldtech.com/forum/?threadid=193189&curpostid=193515%5C

Исходная версия hateyoufeel, :

во многом из-за сложности создания ПО и инструментария для VLIW

Интересно, касается конкретно IA-64 или вообще в целом любого процессора с такой архитектурой?

Любого. VLIW не работает для процессоров общего назначения. Доказано итаником и еблрусом.

Тыц:

За ссылки на швабр прошу прощения.