re PR rtl-optimization/83575 (ICE: verify_flow_info failed (error: multiple hot/cold transitions found))

	PR middle-end/83575
	* cfgrtl.c (rtl_verify_edges): Only verify fixability of partition
	when in layout mode.
	(cfg_layout_finalize): Do not verify cfg before we are out of layout.
	* cfgcleanup.c (try_optimize_cfg): Only verify flow info when doing
	partition fixup.

	* gcc.c-torture/compile/pr83575.c: New testcase.

From-SVN: r256479