assembly - What is the advantage of using segment registers (today)? -

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i trying quite while learn segment registers purpose is? ready know comes past (8086) there 1 mbyte of physical memory. cpu's had 16 bit wide address registers. these 16 address bits address 64k byte. 1mbyte address-space had separated segments each of 64k size.

this seems me requirement past engineers hat work around of somehow limited memory space , such. question advantage of segment registers today? how or use them registers in useful way? if need clarification comment.

arguably, x86-64 long mode technology of "today". there classical segmentation part nonexistent, fs , gs being used practical purposes. fs typically used various thread-local , system data in user mode, while gs used kernel mode. latter use supported swapgs instruction.


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