Remove first_pass_instance from pass_reassoc

Remove first_pass_instance from pass_reassoc

2015-11-16  Tom de Vries  <tom@codesourcery.com>

	* passes.def: Add arg to pass_reassoc pass instantiation.
	* tree-ssa-reassoc.c (reassoc_insert_powi_p): New static variable.
	(acceptable_pow_call, reassociate_bb): Use reassoc_insert_powi_p instead
	of first_pass_instance.
	(execute_reassoc): Add and handle insert_powi_p parameter.
	(pass_reassoc::insert_powi_p): New private member.
	(pass_reassoc::pass_reassoc): Initialize insert_powi_p.
	(pass_reassoc::set_pass_param): New member function.  Set insert_powi_p.
	(pass_reassoc::execute): Call execute_reassoc with extra arg.

From-SVN: r230416