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Comment by qwertyuiop924 | Hacker News Reader

Well, yes. That part sucks. But on x86, everything is like that. I'd rather have one weird, inconsistant thing than an amorphous, ever-shifting mass of them. Which is x86 in a nutshell.

Here's a handy heuristic: if somebody claims to know every x86-64 instruction (or even every x86-32 instruction), you can be at least 90% sure they're lying.

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> Here's a handy heuristic: if somebody claims to know every x86-64 instruction (or even every x86-32 instruction), you can be at least 90% sure they're lying.

I very much prefer ARM myself, but you can probably apply the same rule of thumb to it. There are upwards of 400 instructions both in AArch32 and AArch64, with a fair number of differences between the two.

Edit: I've also posted a breakdown of the immediate limitations for ARM in this thread. It's not that complicated when sticking to the standard instructions.

...But how many of those instructions are just variants of other instructions, but with a different addressing mode?

Fair enough, some instructions have many variants. But I work with ARM assembly almost daily and I still wouldn't remember that, for example, 'VQRDMULH' is a real instruction and it stands for 'Vector Saturating Rounding Doubling Multiply Returning High Half'.

Ah, yes. A fun one. Those exist in x86, too.

I should probably count up x86 against ARM, so I have more than guesses to go on here. Maybe that part of x86 actually better.

> I should probably count up x86 against ARM

It is not easy to tell how many instruction there actually are on x86:

> https://fgiesen.wordpress.com/2016/08/25/how-many-x86-instru...

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