是否有ARM编程转换表XLAT指令？ [英] Is there translate-table XLAT instruction in ARM programming?

问题描述

我是新来的ARM编程开发，我想知道，如果在一个ARM转换表指令XLAT，因为我用它在英特尔8086？

I'm new to ARM programming and I was wondering if there is a translate-table instruction xlat in ARM cause I used it in Intel 8086 ?

推荐答案

我的 XLAT 的理解是，它是一个查找表。

My understanding of XLAT is that it is a table lookup.

这是标准对所有的ARM CPU。这就是所谓的双寄存器间接并看起来，

This is standard to all ARM CPUs. It is called double register indirect and looks like,

 ldrb r0, [r1, r2]  ; get memory location r1+r2 and place in r0.

与缩放的形式是访问2数据结构的半字，字，双字等权力有用的。

The form with scaling is useful for accessing 'half-word', 'word', 'double-word' and other power of 2 data structures.

还有一个的 thumb2 的指令的 TBB 和 TBH ，但这是一个稍微不同的形式，用于开关语句或跳转表。 ARM模式中指令也许作为，

There is also a thumb2 instructions TBB and TBH, but this is a slightly different form that is used for switch statement or jump table. The ARM mode instruction maybe used as,

ldr  pc, [r1, r2, lsl #2]  ; set pc to r1 + 4*r2.

这篇关于是否有ARM编程转换表XLAT指令？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！