先看一段程序 <摘自 /base/boot/Singldr/singldr0.asm, Singularity RDK>
这段代码主要的作用是从real mode跳转到protect mode:
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OPERAND_SIZE_OVERLOAD MACRO
uint8 066h
ENDM
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; push the 16:32 address onto the stack, then "return" to it.
push 0
push Struct_Microsoft_Singularity_BootInfo._Cpu0._GdtPC - Struct_Microsoft_Singularity_BootInfo._Cpu0._GdtNull
mov eax, 07b00h + OFFSET BootPhase3
push eax
OPERAND_SIZE_OVERLOAD ; 这一句什么意思。。。?
retf
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