tree-optimization/103188 - avoid running ranger on not-up-to-date SSA

tree-optimization/103188 - avoid running ranger on not-up-to-date SSA

The following splits loop header copying into an analysis phase
that uses ranger and a transform phase that can do without to avoid
running ranger on IL that has SSA form not updated.

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

	PR tree-optimization/103188
	* tree-ssa-loop-ch.c (should_duplicate_loop_header_p):
	Remove query parameter, split out check for size
	optimization.
	(ch_base::m_ranger, cb_base::m_query): Remove.
	(ch_base::copy_headers): Split processing loop into
	analysis around which we allocate and use ranger and
	transform where we do not.
	(pass_ch::execute): Do not allocate/free ranger here.
	(pass_ch_vect::execute): Likewise.

	* gcc.dg/torture/pr103188.c: New testcase.