[LLVMdev] GCC/LLVM frame pointer incompatibility on ARM

[Reid Kleckner]

On Fri, Jul 18, 2014 at 4:59 PM, Jim Grosbach <grosbach at apple.com> wrote:

> It's not just sanitizers that need to be able to get fast, accurate stack
> traces.  Consider sampling profilers that capture call stacks.  Using the
> unwind tables is disruptively slow to the process under profile.
>
>
> Why not do the unwind table parsing after the fact? Especially for a
> profiler, there’s no reason to do that during the actual profile collection.
>

I'm not sure how that would work, without memcpy-ing the entire stack.  If
you don't have frame pointers you can't walk upwards to find the return
addresses to save, at least not without... looking at the unwind tables.  :)
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