Фото: Scott Peterson / Getty Images
Nearly every protection-related instruction -- far CALL, far JMP, far RET, INT, IRET, MOV to segment register, task switch -- needs to load a segment descriptor from the GDT or LDT. The 386 microcode centralizes this into a shared subroutine called LD_DESCRIPTOR, which reads the 8-byte descriptor from memory and feeds the high DWORD (containing Type, DPL, S, and P bits) to the Test PLA for validation.
安德烈·塔可夫斯基和儿子安德留什卡 图/《殉道学：塔可夫斯基日记 1970-1986》）
Фото: Сергей Бобылев / РИА Новости