Using apcs frame layout

[Anton Kozlov]

x86 unwinded by just memory content, without dwarf info. This achived
with gcc's -fno-omit-frame-pointer flag, which always generate known
frame layout (actually, it disables optimizations for leaf functions,
but it have desired effect)

We have similar gcc flag on arm that forces known frame layout: -mapcs
-frame. But, after -fno-omit-frame-pointer on x86, java and native
frame layouts are same; and after -mapcs-frame native and java frames
have different layout on arm.

It's what I suggest, to have openjdk options that forces java and
native frame layout to be same, just as on other platforms.

Thanks,
Anton

On Mon, 2016-03-28 at 10:20 +0100, Andrew Haley wrote:
> On 28/03/16 08:50, Anton Kozlov wrote:
> > May be I missed something, and there is some general-purpose way
> > for
> > perf to unwind custom frame layout, as it is in aarch32-port?
> 
> I haven't looked.  Valgrind has its own unwinder which uses the
> DWARF info, and GCC people will tell you that's the only right
> way to do it.
> 
> What does x86-64 do?
> 
> Andrew.
>