Re: Go to CLAX and enjoy the difference


Frank Kotler wrote:
>
> Yeah, but different registers. What happened to ebx, ecx, edx, esi, edi,
> (ebp in some calls)...
>
> Well I suppose it's because syscall trashes [e|r]cx... Uses it to store
> [e|r]ip, I guess... ???
>
> Best,
> Frank

I intentionally did not set up a stack frame in those examples. You
have the
option in amd64 to use %rbp as another register and use %rsp to index
the
the stack. This is explained in a footnote in the ABI.

You have a lot more registers to work with. There is a table in the
ABI that tells you what registers are used for what parameter and which
ones are preserved across function calls.

Floats are now passed using the %xmm set of registers. I would post an
example, but I do not understand 128 bit media yet.

Cheers,

Brian

.

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