re PR tree-optimization/57233 (Vector lowering of LROTATE_EXPR pessimizes code)

re PR tree-optimization/57233 (Vector lowering of LROTATE_EXPR pessimizes code)

	PR tree-optimization/57233
	PR tree-optimization/61299
	* tree-vect-generic.c (get_compute_type, count_type_subparts): New
	functions.
	(expand_vector_operations_1): Use them.  If {L,R}ROTATE_EXPR
	would be lowered to scalar shifts, check if corresponding
	shifts and vector BIT_IOR_EXPR are supported and don't lower
	or lower just to narrower vector type in that case.
	* expmed.c (expand_shift_1): Fix up handling of vector
	shifts and rotates.

	* gcc.dg/pr57233.c: New test.
	* gcc.target/i386/pr57233.c: New test.
	* gcc.target/i386/sse2-pr57233.c: New test.
	* gcc.target/i386/avx-pr57233.c: New test.
	* gcc.target/i386/avx2-pr57233.c: New test.
	* gcc.target/i386/avx512f-pr57233.c: New test.
	* gcc.target/i386/xop-pr57233.c: New test.

From-SVN: r212063