PR tree-optimization/32216

	PR tree-optimization/32216
	* tree-vectorizer.c (supportable_widening_operation): Determine
	signedness of FIX_TRUNC_EXPR from output operand.
	(supportable_narrowing_operation): Ditto.
	* tree-vect-generic.c (expand_vector_operations_1): Determine
	signedness of VEC_UNPACK_FLOAT_HI_EXPR and VEC_UNPACK_FLOAT_LO_EXPR
	from input operand.

testsuite/ChangeLog:

	PR tree-optimization/32216
	* gcc.dg/vect/pr32216.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@125482 138bc75d-0d04-0410-961f-82ee72b054a4