gcc/

	gcc/
	Backport from trunk r237331.
	2016-06-11  Jiong Wang  <jiong.wang@arm.com>

	PR target/71061
	* config/arm/arm-protos.h (arm_attr_length_pop_multi): New declaration.
	* config/arm/arm.c (arm_attr_length_pop_multi): New function to return
	length for pop patterns.
	(arm_attr_length_push_multi): Update comments.
	* config/arm/arm.md (*load_multiple_with_writeback): Set "length"
	attribute.
	(*pop_multiple_with_writeback_and_return): Likewise.
	(*pop_multiple_with_return): Likewise.

Change-Id: I19b35183be89cdcab6e40b6c727334342873e9ea