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0 pointspvg7y ago0 comments

It's analogous to JVM bytecode.

That's only true in the way everything is analogous to everything.

0 comments

I think it's a good analogy because it's saying that nontrivial optimizations happen below the code layer.

In early CPUs, nothing was optimized. They just executed your instructions. Now there are nontrivial optimizations and rewriting, just like the JVM.

coldtea7y ago

Nope, also in the way the parent explains right after that sentence.

pvgOP7y ago

It's a pretty terrible analogy in nearly every obvious technical way. What an x86 cpu does with its instructions is almost but not entirely unlike what a JVM does.

admax88q7y ago

None of the "registers" in x86 assembly are real. Few of the instructions are implemented in hardware, most are impelmented in software microcode.

Advanced hardware will re-order and pipeline instructions based upon data dependencies.

Sure it's not doing the exact same things the JVM does with bytecode but the point is that x86 assembly is not the language of the hardware. It's a language that the hardware+firmware knows how to interpret and optimize at runtime similar to what your JVM does with java bytecode.

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