[LLVMdev] dmb ishld in AArch64

Chengyu Song csong84 at gatech.edu
Tue Dec 9 13:30:57 PST 2014


> On Dec 9, 2014, at 3:45 PM, Tim Northover <t.p.northover at gmail.com> wrote:
> 
>> I guess it's because we disabled the integrated-asm, so it won't complain when compiling the kernel.
> 
> No, it's something different. The inline assembly (for whatever
> reason) says to use a "dmb ishst" rather than an "stlr". I don't
> actually think the reason is that important, it's just surprising
> because I'd expect stlr to be more efficient.

I see .... guess I'm using an old version of Linux kernel ... from the Android branch ...

> Thanks for the IR snippet (I agree, it does look like the order is
> reasonable there), but it's not really enough to debug the problem. We
> need an actual Module we can compile and examine to have a hope of
> finding out what's going on.

You mean the source code I'm compiling? 

Thanks,
Chengyu



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