第一篇

尝试着记录学习过程

#include<>

# offset 512, entry point

        .globl        _start
_start:
                # Explicitly enter this as bytes, or the assembler
                # tries to generate a 3-byte jump here, which causes
                # everything else to push off to the wrong offset.
                .byte        0xeb                # short (2-byte) jump
                .byte        start_of_setup-1f

        #第一条指令，这是一条短跳转，接下来到start_of_setup。执行设置堆栈清空setup的bss段等操作，然后跳转到boots/main.c中。

# Jump to C code (should not return)
        calll        main #到C代码去了