tree-optimization/92328 fix value-number with bogus type

tree-optimization/92328 fix value-number with bogus type

We were actually value-numbering two entities with different type
the same rather than just having the same representation in the
hashtable.  The following fixes that by wrapping the value in a
to be inserted VIEW_CONVERT_EXPR.

2020-01-21  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/92328
	* tree-ssa-sccvn.c (vn_reference_lookup_3): Preserve
	type when value-numbering same-sized store by inserting a
	VIEW_CONVERT_EXPR.
	(eliminate_dom_walker::eliminate_stmt): When eliminating
	a redundant store handle bit-reinterpretation of the same value.

	* gcc.dg/torture/pr92328.c: New testcase.