02.07.2013 Views

Uboot中start.S源码的指令级的详尽解析

Uboot中start.S源码的指令级的详尽解析

Uboot中start.S源码的指令级的详尽解析

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对于此格式,我们可以拿:<br />

图表 31 数据处理指令的指令格式<br />

arm-linux-objdump –d u-boot > dump_u-boot.txt<br />

中得到的汇编代码中关于:<br />

ldr r0, =0x53000000<br />

所对应的,真正的汇编代码:<br />

33d00068: e3a00453 mov r0, #1392508928 ; 0x53000000<br />

来分析,就容易看懂了:<br />

mov r0, #1392508928<br />

= mov r0, #0x53000000<br />

的作用就是,把0x53000000移动到r0中去。<br />

其对应的二进制指令是上面的:<br />

0xe3a00453 = 1110 0011 1010 0000 0000 0100 0101 0011 b<br />

下面对照mov指令的格式,来分析这些位所对应的含义:

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