gdb/

gdb/
2012-11-14  Daniel Jacobowitz  <dan@codesourcery.com>
	    Yao Qi  <yao@codesourcery.com>

	* arm-tdep.c (arm_addr_bits_remove): Do not adjust the low
	bit of EXC_RETURN.
	(arm_m_exception_cache, arm_m_exception_this_id)
	(arm_m_exception_prev_register, arm_m_exception_unwind_sniffer)
	(arm_m_exception_unwind): New.
	(arm_gdbarch_init): Register arm_m_exception_unwind.