[PowerPC] PR23774 stack backchain broken saga

[Segher Boessenkool]

On 10 sep 2005, at 02:03, Richard Henderson wrote:

> On Sat, Sep 10, 2005 at 01:00:04AM +0930, Alan Modra wrote:
>> 2) Next, I defined parallels to keep things together.  Like the
>> following, with another for DImode.
>
> This seems most reasonable to me.

Especially as the ABI states that the write of the backlink
and the stack pointer update _have_ to be done in one insn.
Not that I can see how e.g. your options 4 and 5 would be
unsafe in this case, but those are violating what the ABI
dictates.


Segher