PR target/96342 Change field "simdlen" into poly_uint64

PR target/96342 Change field "simdlen" into poly_uint64

This is the first patch of PR96342. In order to add support for
"omp declare simd", change the type of the field "simdlen" of
struct cgraph_simd_clone from unsigned int to poly_uint64 and
related adaptation. Since the length might be variable for the
SVE cases.

2020-11-03  Yang Yang  <yangyang305@huawei.com>

gcc/ChangeLog:

	* cgraph.h (struct cgraph_simd_clone): Change field "simdlen" of
	struct cgraph_simd_clone from unsigned int to poly_uint64.
	* config/aarch64/aarch64.c
	(aarch64_simd_clone_compute_vecsize_and_simdlen): adaptation of
	operations on "simdlen".
	* config/i386/i386.c (ix86_simd_clone_compute_vecsize_and_simdlen):
	Printf formats update.
	* gengtype.c (main): Handle poly_uint64.
	* omp-simd-clone.c (simd_clone_mangle): Likewise.Re
	(simd_clone_adjust_return_type): Likewise.
	(create_tmp_simd_array): Likewise.
	(simd_clone_adjust_argument_types): Likewise.
	(simd_clone_init_simd_arrays): Likewise.
	(ipa_simd_modify_function_body): Likewise.
	(simd_clone_adjust): Likewise.
	(expand_simd_clones): Likewise.
	* poly-int-types.h (vector_unroll_factor): New macro.
	* poly-int.h (constant_multiple_p): Add two-argument versions.
	* tree-vect-stmts.c (vectorizable_simd_clone_call): Likewise.