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Date: Tue, 11 Feb 2014 11:52:17 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Stephane Eranian <eranian@google.com>
Cc: Don Zickus <dzickus@redhat.com>,
        Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
        LKML <linux-kernel@vger.kernel.org>, Jiri Olsa <jolsa@redhat.com>,
        Joe Mario <jmario@redhat.com>, Richard Fowles <fowles@inreach.com>
Subject: Re: [PATCH 00/21] perf, c2c: Add new tool to analyze cacheline
 contention on NUMA systems
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On Tue, Feb 11, 2014 at 11:35:45AM +0100, Stephane Eranian wrote:
> On Tue, Feb 11, 2014 at 8:14 AM, Peter Zijlstra <peterz@infradead.org> wrote:
> >
> > That blows; how much is missing?
> 
> They need to annotate load and stores. I asked for that feature a while ago.
> It will come.

And there is no way to deduce the information? We have type information
for all arguments and local variables, right? So we can follow that.

struct foo {
	int ponies;
	int moar_ponies;
};

struct bar {
	int my_ponies;
	struct foo *foo;
};

int moo(struct bar *bar)
{
	return bar->foo->moar_ponies;
}

Since we have the argument type, we can find the type for both loads,
the first load:

  *bar+8, we know is: struct foo * bar::foo
  *foo+4, we know is: int foo::moar_ponies

Or am I missing something?