Backport from mainline:

	Backport from mainline:
	2014-10-20  Uros Bizjak  <ubizjak@gmail.com>

	* varasm.c (const_alias_set): Remove.
	(init_varasm_once): Remove initialization of const_alias_set.
	(build_constant_desc): Do not set alias set to const_alias_set.

	Backport from mainline:
	2014-10-14  Uros Bizjak  <ubizjak@gmail.com>

	PR rtl-optimization/63475
	* alias.c (true_dependence_1): Always use get_addr to extract
	true address operands from x_addr and mem_addr.  Use extracted
	address operands to check for references with alignment ANDs.
	Use extracted address operands with find_base_term and
	base_alias_check. For noncanonicalized operands call canon_rtx with
	extracted address operand.
	(write_dependence_1): Ditto.
	(may_alias_p): Ditto.  Remove unused calls to canon_rtx.

	Backport from mainline:
	2014-10-10  Uros Bizjak  <ubizjak@gmail.com>

	PR rtl-optimization/63483
	* alias.c (true_dependence_1): Do not exit early for MEM_READONLY_P
	references when alignment ANDs are involved.
	(write_dependence_p): Ditto.
	(may_alias_p): Ditto.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_9-branch@217119 138bc75d-0d04-0410-961f-82ee72b054a4