[LLVMdev] dmb ishld in AArch64

[Tim Northover]

On 9 December 2014 at 16:01, Chengyu Song <csong84 at gatech.edu> wrote:
> I'm using r223407.

Just trying out this build now. Hopefully I'll be able to see the
error too there.

>  Switching to a clean built on r223853, it still gives me:
>
>     ldr x8, [x21,#8]
>     stp x21, x8, [x19]
>     dmb ishst
>     ldr x8, [x19,#8]
>     str x19, [x8]
>     str x19, [x21,#8]

Isn't that correct though? The problematic "str" has been folded into
the "stp" instruction, so "x19 + 8" is written before it gets read.

Cheers.

Tim.