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One of the problems with VLIW architectures is lack of binary compatibility between CPU generations. Suppose you had 4-way VLIW architecture and the next generation become 8-way. Even if new CPU will be able to run old 4-way code, it will twice as slower, I.e you need to recompile your software.



I imagine just-in-time compilation has a lot to offer there. Managed runtimes already have the advantage of being able to automatically tailor the machine code to the target CPU.

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I imagine that Transmeta had the same imagination.

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In a sense, they did. And they did famously fail to meet expectations.

But considering that nowadays other stacks which rely on jitting regularly achieve real-world performance that is competitive with much native-compiled software, it seems safe to presume that Transmeta's performance problems stemmed from reasons beyond the basic idea behind CMS.

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GPU vendors circumvent this limitation by not documenting actual ISA and only documenting virtual ISA (PTX for NVidia, CAL for AMD).

GPU drivers dynamically recompile "Virtual ISA" into actual ISA when running kernel or shader first time.

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