[PR 80622] Treat const pools as initialized in SRA

[PR 80622] Treat const pools as initialized in SRA

2017-05-04  Martin Jambor  <mjambor@suse.cz>

	PR tree-optimization/80622
	* tree-sra.c (comes_initialized_p): New function.
	(build_accesses_from_assign): Only set write lazily when
	comes_initialized_p is false.
	(analyze_access_subtree): Use comes_initialized_p.
	(propagate_subaccesses_across_link): Assert !comes_initialized_p
	instead of testing for PARM_DECL.

testsuite/
	* gcc.dg/tree-ssa/pr80622.c: New test.

From-SVN: r247604