Add v2di support for nvptx

Add v2di support for nvptx

2017-07-19  Tom de Vries  <tom@codesourcery.com>

	* config/nvptx/nvptx-modes.def: Add V2DImode.
	* config/nvptx/nvptx-protos.h (nvptx_data_alignment): Declare.
	* config/nvptx/nvptx.c (nvptx_ptx_type_from_mode): Handle V2DImode.
	(nvptx_output_mov_insn): Handle lack of mov.b128.
	(nvptx_print_operand): Handle 'H' and 'L' codes.
	(nvptx_vector_mode_supported): Allow V2DImode.
	(nvptx_preferred_simd_mode): New function.
	(nvptx_data_alignment): New function.
	(TARGET_VECTORIZE_PREFERRED_SIMD_MODE): Redefine to
	nvptx_preferred_simd_mode.
	* config/nvptx/nvptx.h (STACK_BOUNDARY, BIGGEST_ALIGNMENT): Change from
	64 to 128 bits.
	(DATA_ALIGNMENT): Define.  Set to nvptx_data_alignment.

	* config/nvptx/nvptx.md (VECIM): Add V2DI.

	* gcc.target/nvptx/decl-init.c: Update alignment.
	* gcc.target/nvptx/slp-2-run.c: New test.
	* gcc.target/nvptx/slp-2.c: New test.
	* gcc.target/nvptx/v2di.c: New test.

	* testsuite/libgomp.oacc-c/vec.c: New test.

From-SVN: r250341