Alon Bar-Lev wrote:
On 8/28/06, Matt Domsch <[email protected]> wrote:No reason. I was just trying to be careful, not leaving data in the upper bits of those registers going uninitialized. If we know they're not being used ever, then it's not a problem. But I don't think that's the source of the command line size concern, is it?Since the cmd_line_ptr is 32bit, we can load the lower 16bits into si, ignoring the upper 16bits, or we can use esi for all references. I think using esi for all references is cleaner...
Bullshit. You're in 16 bit mode, and your segment limits are only 64K in size, so you HAVE to use a segment:offset type addressing:
Thus, you want to do something like this. movl cmd_line_ptr, %esi movl %esi, %eax shrl $4, %eax mov %ax, %es andw $0xf, %si... and then address it through es:si. Anything else is total, utterly and completely wrong.
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