X在组装中的EAX，EBX，ECX ...中是什么意思? [英] What does X mean in EAX,EBX,ECX ... in assembly?

问题描述

Google不显示结果

有人知道吗?

解决方案

X表示 对 ，至少回到8080.它有8位寄存器B，C，D，E，H，L(以及其他)也可以成对使用(BC，DE和HL). BC和DE对主要用于16位算术. HL对通常保存一个存储器地址. X用于 对 的一些示例:

LXI  D,12ABH    ; "load pair immediate"
DCX  B          ; "decrement pair"
STAX D          ; "store A (indirect) at pair"

快速进入8086.它具有寄存器AL，AH，BL，BH，CL，CH，DL，DH，与8080类似，可以成对使用:AX，BX，CX，DX. /p>

正如其他人指出的那样，32位寄存器名称中的E表示扩展.

Google doesn't show the result,

Anyone knows?

解决方案

The X means pair, and goes back to at least the 8080. It had 8-bit registers B,C,D,E,H,L (among others) which could also be used in pairs (BC, DE and HL). The BC and DE pairs were used mostly for 16-bit arithmetic; the HL pair generally held a memory address. Some examples of the usage of X for pair:

LXI  D,12ABH    ; "load pair immediate"
DCX  B          ; "decrement pair"
STAX D          ; "store A (indirect) at pair"

Fast forward to the 8086. It has registers AL,AH,BL,BH,CL,CH,DL,DH, which, similarly to the 8080, can be used in pairs: AX, BX, CX, DX.

As others have pointed out, the E in the 32-bit register names means extended.

这篇关于X在组装中的EAX，EBX，ECX ...中是什么意思?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！