The LDS instruction specifically reads these values from memory and places the offset into a destination general-purpose register (GPR) and the segment selector into the register. The Syntax LDS destination_reg, source_mem
In the spring of 1992, Eleanor, a young and slightly reckless systems programmer, found herself hunched over a beige 386 DX/40. The machine groaned under MS-DOS 5.0, and in front of her was a nightmare: a core dump from a geological modeling program she’d inherited.
LDS = Load a far pointer from memory into DS + r16/r32 . Essential for real-mode, irrelevant for 64-bit. A textbook example of a CISC instruction optimized for the segmented memory models of the 1980s.
In this example, the LDS instruction loads a data segment selector from memory address 0x1000 into the SI register.