[NDS32] Add intrinsic functions for unalignment memory access.

[NDS32] Add intrinsic functions for unalignment memory access.

gcc/
	* config/nds32/constants.md (unspec_element): New enum.
	* config/nds32/constraints.md (Umw): New constraint.
	* config/nds32/nds32-intrinsic.c: Add more builtin functions.
	* config/nds32/nds32-intrinsic.md: Likewise.
	* config/nds32/nds32-md-auxiliary.c (nds32_regno_to_enable4): New.
	(nds32_valid_smw_lwm_base_p): New.
	(nds32_output_smw_single_word): New.
	(nds32_output_lmw_single_word): New.
	(nds32_expand_unaligned_load): New.
	(nds32_expand_unaligned_store): New.
	* config/nds32/nds32-protos.h (nds32_valid_smw_lwm_base_p): Declare.
	(nds32_output_smw_single_word): Declare.
	(nds32_output_lmw_single_word): Declare.
	(nds32_expand_unaligned_load): Declare.
	(nds32_expand_unaligned_store): Declare.
	* config/nds32/nds32.h (nds32_builtins): Add NDS32_BUILTIN_UALOAD_HW,
	NDS32_BUILTIN_UALOAD_W, NDS32_BUILTIN_UALOAD_DW,
	NDS32_BUILTIN_UASTORE_HW, NDS32_BUILTIN_UASTORE_W,
	NDS32_BUILTIN_UASTORE_DW.
	* config/nds32/predicates.md (nds32_lmw_smw_base_operand): New
	predicate.

Co-Authored-By: Chung-Ju Wu <jasonwucj@gmail.com>
Co-Authored-By: Monk Chiang <sh.chiang04@gmail.com>
From-SVN: r258214