How many registers does an x86-64 CPU have? (2020)
I dislike weird semantic hoop-jumping articles like this. It purposefully obfuscates a simple question to make it seem more complex. Just in the GPR section, the answer is simple...in long mode there are 16 that can be subdivided. There aren&#x27;t 58 additional registers because of that.<p>Or, to get more specific, how many pieces of data are there in this union:<p><pre><code>    union Registers {
      struct { unsigned short int AF; };
      struct { unsigned char F, A; };
    } regs;
</code></pre>
Most would say one, with multiple interfaces. It might be &quot;controversial&quot; to some that consider each field independent, but I&#x27;d wager that they&#x27;re a rare exception.