RFR(S): 8016696: PPC64 (part 4): add relocation for trampoline stubs

[Vladimir Kozlov]

I don't see problems with it. I asked Roland to look in also.

Can you push it before Part 3 (which may need some time to adjust closed sources)?

Thanks,
Vladimir

On 6/17/13 5:24 AM, Lindenmaier, Goetz wrote:
> Hi,
>
> On PPC, we use special stubs we call trampoline stubs for calls to
>
> target addresses that can not be encoded as offset in the branch
>
> instruction.
>
> A trampoline allows to encode a small branch in the code, even if
>
> there is the chance that this branch can not reach all possible code
>
> locations. If the relocation finds that a branch is too far for the
>
> instruction in the code, it can patch it to jump to the trampoline
>
> where is sufficient space for a far branch.
>
> To implement this, we extended the relocations by a new kind,
>
> trampoline_stub_Relocation:
>
> http://cr.openjdk.java.net/~goetz/webrevs/8016696-trampoline/
>
> Aditionally to the code in 0004_opto-trampoline_relocations.patch
>
> I added debug printing functionality.
>
> Could I get a review on this change, please?
>
> Thanks,
>
>    Goetz.
>