Re: [RFC] problem fetching inferior memory due to breakpoint

[Daniel Jacobowitz <drow at false dot org>]

On Wed, Apr 26, 2006 at 12:05:17PM -0700, Joel Brobecker wrote:
> We actually scan the function prologue during the step operation as
> opposed to during the "bt", because we need to determine where we are,
> and that causes us to create the frame ID for frame 0, which means
> scanning the function prologue (not actually verified, all from memory,
> may be incorrect - but the fact is correct: we compute the frame ID
> during the step).

Which seriously blows for performance.

> I'm not exactly sure yet as to why we don't see this problem on x86-linux.
> But all works fine there as far as I can tell.

Try removing .debug_frame, to trigger the prologue analyzer?

> I looked at the gdb-patches archives, and Andrew said at the time
> that we should use get_frame_memory. The problem is that I don't see
> how get_frame_memory() will help, since all it does is calling
> read_memory(), which brings us back to our initial problem.

Try safe_frame_unwind_memory, the other caller of
deprecated_read_memory_nobpt.  Many other prologue analyzers already
seem to use that.

-- 
Daniel Jacobowitz
CodeSourcery