Re: [PATCH v2] powerpc: slightly improve cache helpers

On Fri, Jul 19, 2019 at 10:23:03AM -0500, Segher Boessenkool wrote:

On Thu, Jul 18, 2019 at 08:24:56PM -0700, Nathan Chancellor wrote:

quoted

On Mon, Jul 08, 2019 at 11:49:52PM -0700, Nathan Chancellor wrote:

quoted

On Tue, Jul 09, 2019 at 07:04:43AM +0200, Christophe Leroy wrote:

quoted

Is that a Clang bug ?

No idea, it happens with clang-8 and clang-9 though (pretty sure there
were fixes for PowerPC in clang-8 so something before it probably won't
work but I haven't tried).

quoted

Do you have a disassembly of the code both with and without this patch in
order to compare ?

I can give you whatever disassembly you want (or I can upload the raw
files if that is easier).

What disassembly/files did you need to start taking a look at this? I
can upload/send whatever you need.

A before and after of *only this patch*.  And then look at what changed;
it maybe be obvious what is the problem to you, as well, so look at it
yourself first?


Segher

Thanks, I will go ahead and disassemble the full kernel given that those
helpers are everywhere and see what I can find. I'll reach out again if
I can't come up with anything.

Thanks for the advice!
Nathan