The writer G.K. Chesterton once said that before you knock anything down, you ought to know how it got there in the first place. So before we show for-profit publishers the pointy end of a pitchfork, we ought to know where they came from and why they persist.
We are not asking "do the points fit in this particular semicircle?" We are asking "do the points fit in any semicircle?" The semicircle gets to move. It can be anchored at whichever point makes it work.
，这一点在搜狗输入法下载中也有详细论述
分析：美以摧毀伊朗現任領導層背後的戰略是什麼？
Besides the Test PLA, the 386 has another PLA called the Entry PLA that maps opcodes to microcode entry points. One of its input bits is a "protected mode" flag. Many instructions have both a real-mode and a protected-mode entry point -- for instance, MOV ES, reg maps to address 009 (a single microcode line) in real mode, but to 580 (which initiates a full descriptor load with protection tests) in protected mode. The trick that makes V86 work is to define this flag as: