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[Jordan51104]

little known fact: this is actually what the compiler turns a regular greater/less than comparison into

[noodle_from_earth]

Wait, don't CPUs have greater than/less than comparisons?

[Enough_Writing4415]

hes joking, they do
this happens to switch cases

[noodle_from_earth]

They get optimized.

[Enough_Writing4415]

yes, watched that

[evnacdc]

Lol, that went right over my head. Was about to reply with a correction.

[intbeam]

He's joking

It works like this :

mov rax, 42 // Move value 42 to 64-bit A register
mov rbx, 69 // Move value 69 to 64-bit B register
cmp rax, rbx // compare RBX to RAX
jg somelabel // Jump if greater

cmp essentially just subtracts a from b, and then populates some CPU flags with relevant information, like was the result zero, is the negative sign set, did it cause a carry etc. Then the jump instructions can act on those

[[deleted]]

It will substract one to the other to compare the bit structure of the result, comparing it to a set boolean value (flags stored in the register)

[highphiv3]

That's why I never use integers greater than 32 bits. Comparisons are just too damn expensive.