Re: r13 in the kernel

Frank Wille <[email protected]>
Newsgroups gmane.os.netbsd.ports.powerpc
Organization Privates Internet Ostwestfalen/Lippe e.V.
Message-ID <[email protected]>
Matt Thomas wrote:

>> Is it really safe to do so? IIRC the V.4-ABI defines r13 as small data
>> base register, but when small data is not used it should be a normal
>> non-volatile register, like r14 - r31.
>> The kernel is compiled with -msdata=none.
>
> Yes.  From gcc rs6000.h:
>
> On System V implementations, r13 is fixed and not available for use.

Hmm.. ok, then I remembered wrong.

Indeed, I found no bad usage of r13 while scanning through a disassembled
kernel.

-- 
Frank Wille
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