Learn CFG cleanup to transform single case switches to gcond.

Learn CFG cleanup to transform single case switches to gcond.

2017-09-05  Martin Liska  <mliska@suse.cz>

	PR tree-optimization/82032
	* tree-cfg.c (generate_range_test): New function.
	* tree-cfg.h (generate_range_test): Declared here.
	* tree-cfgcleanup.c (convert_single_case_switch): New function.
	(cleanup_control_expr_graph): Use it.
	* tree-switch-conversion.c (try_switch_expansion): Remove
	assert.
	(emit_case_nodes): Use generate_range_test.
2017-09-05  Martin Liska  <mliska@suse.cz>

	PR tree-optimization/82032
	* g++.dg/other/pr82032.C: New test.
	* gcc.dg/tree-ssa/pr68198.c: Update scanned pattern.
	* gcc.dg/tree-ssa/vrp34.c: Likewise.
	* gcc.dg/switch-10.c: Likewise.

From-SVN: r251690