Re: [PATCH v11 8/8] PPC: Don't use hardcoded opcode for ePAPR hcall invocation

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 07/02/2012 12:34 PM, Timur Tabi wrote:
> Scott Wood wrote:
> 
>> Hmm.  The comment says, "XER, CTR, and LR are currently listed as
>> clobbers because it's uncertain whether they will be clobbered."  Maybe
>> it dates back to when the ABI was still being discussed?  Timur, do you
>> recall?
> 
> Nope, sorry.  I'm sure we discussed this and looked at the code.  My guess
> is that we weren't certain what the compiler was going to do at the time.

I'm not sure how the compiler is involved here -- we're just telling it
what our asm code (and the asm code in the hypervisor) will do.

>  I'm still a little confused.  Which inline assembly code is clobbering LR?
>  Are you talking about the "BL" instruction, which wasn't there before?

Yes, I didn't realize that LR had been in the clobber list before that.

-Scott

--
To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [KVM Development]     [KVM ARM]     [KVM ia64]     [Linux Virtualization]     [Linux USB Devel]     [Linux Video]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Big List of Linux Books]

  Powered by Linux