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Larrabee ISA Revealed
David Greene writes "Intel has released information on Larrabee's ISA. Far more than an instruction set for graphics, Larrabee's ISA provides x86 users with a vector architecture reminiscent of the top supercomputers of the late 1990s and early 2000s. '... Intel has also been applying additional transistors in a different way — by adding more cores. This approach has the great advantage that, given software that can parallelize across many such cores, performance can scale nearly linearly as more and more cores get packed onto chips in the future. Larrabee takes this approach to its logical conclusion, with lots of power-efficient in-order cores clocked at the power/performance sweet spot. Furthermore, these cores are optimized for running not single-threaded scalar code, but rather multiple threads of streaming vector code, with both the threads and the vector units further extending the benefits of parallelization.' Things are going to get interesting."
If developers are too stupid to code for it, it won't go anywhere. This is sounding a lot like the PS3 architecture in complexity. Parallelism is not that hard to deal with, but you have to know what you're doing. Sadly, few do. Try again in ten years.
There are lots of instructions and other craft inside 80x86 processors that occupy silicon that is never used. A clean break from 80x86 is needed. Legacy 80x86 code can run perfectly in emulation (and need not be slow, using JIT techniques).
What I like most about Larrabee is the scatter-gather operations. One major problem in vectorized architectures is how to load the vectors with data coming from multiple sources. the Larrabee ISA solves this neatly by allowing vectors to be loaded from different sources in hardware and in parallel, thus making loading/storing vectors a very fast operation.
The programming languages that will benefit from Larrabee though will not be C/C++. It will be Fortran and the purely functional programming languages. Unless C/C++ has some extensions to deal with the pointer aliasing issue, that is.
This isn't really x86, in my opinion; it's x86 with a separate set of very obviously graphics-oriented instructions bolted on top. Since getting decent performance will require using the new instructions and a new programming model almost exclusively, what's the point of the x86 bit? Well, other than marketing reasons and to prevent companies like NVidia releasing their own version, of course...
Your post is saccharine, condescending, vapid, and irrelevant to the subject at hand.
If you have an opinion on anything I was actually discussing, please share it. As an example, you could explore the visual differences between the two contrasted films, the science behind the 'uncanny valley, or perhaps discuss the merits of rotoscoping in general.
"I liked the movie. Some of my friends liked the movie."
The inanity is stupefying.
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