Apply TLC to control dependence compute

Apply TLC to control dependence compute

This makes the control dependence compute avoid a find_edge
and optimizes allocation by embedding the bitmap head into the
vector of control dependences instead of allocating all of them.
It also uses a local bitmap obstack.

The bitmap changes make it necessary to shuffle some includes.

2021-11-10  Richard Biener  <rguenther@suse.de>

	* cfganal.h (control_dependences::control_dependence_map):
	Embed bitmap_head.
	(control_dependences::m_bitmaps): New.
	* cfganal.c (control_dependences::set_control_dependence_map_bit):
	Adjust.
	(control_dependences::clear_control_dependence_bitmap):
	Likewise.
	(control_dependences::find_control_dependence): Do not
	find_edge for the abnormal edge test.
	(control_dependences::control_dependences): Instead do not
	add abnormal edges to the edge list.  Adjust.
	(control_dependences::~control_dependences): Likewise.
	(control_dependences::get_edges_dependent_on): Likewise.
	* function-tests.c: Include bitmap.h.

gcc/analyzer/
	* supergraph.cc: Include bitmap.h.

gcc/c/
	* gimple-parser.c: Shuffle bitmap.h include.