cfgexpand: Handle WIDEN_{PLUS,MINUS}_EXPR and...

cfgexpand: Handle WIDEN_{PLUS,MINUS}_EXPR and VEC_WIDEN_{PLUS,MINUS}_{HI,LO}_EXPR in expand_debug_expr [PR108967]

When these tree codes were introduced, expand_debug_expr hasn't been
updated to handle them.  For the VEC_*_EXPR we currently mostly punt, the
non-vector ones can be handled easily.  In release compilers this doesn't
ICE, but with checking we ICE so that we make sure to handle all the needed
tree codes there.

2023-03-01  Jakub Jelinek  <jakub@redhat.com>

	PR debug/108967
	* cfgexpand.cc (expand_debug_expr): Handle WIDEN_{PLUS,MINUS}_EXPR
	and VEC_WIDEN_{PLUS,MINUS}_{HI,LO}_EXPR.

	* g++.dg/debug/pr108967.C: New test.