Eric, Jakub,
Thanks for your inputs, I've applied them. Updated patch is attached.

So, one more time:

ChangeLog entry:
2011-07-06  Kirill Yukhin  <kirill.yukhin@intel.com>

        PR middle-end/49519
        * calls.c (mem_overlaps_already_clobbered_arg_p): Additional
        check if address is stored in register. If so - give up.
        (check_sibcall_argument_overlap_1): Do not perform check of
        overlapping when it is call to address.

tessuite/ChangeLog entry:
2011-07-06  Kirill Yukhin  <kirill.yukhin@intel.com>

        * g++.dg/torture/pr49519.C: New test.

Bootstrapped, new test fails without the patch, passes when it is applied.
This fixes the problem with SPEC2006/447.dealII miscompile

Ok for trunk?

Thanks, K