Hi,

This patch implements support for all vldr/vstr MVE variants, including 
the gather loads and scatter stores.

gas/ChangeLog:

2019-05-01  Andre Vieira  <andre.simoesdiasvieira@arm.com>

	* config/tc-arm.c (struct arm_it): Make immisreg
         field larger to hold type of register.
	(enum shift_kind): Add SHIFT_UXTW shift kind.
	(enum parse_shift_mode): Add SHIFT_UXTW_IMMEDIATE
         shift mode.
	(parse_shift): Handle new shift type.
	(parse_address_main): Accept new addressing modes.
	(M_MNEM_vstrb, M_MNEM_vstrh, M_MNEM_vstrw, M_MNEM_vstrd,
         M_MNEM_vldrb, M_MNEM_vldrh, M_MNEM_vldrw, M_MNEM_vldrd):
         New instruction encodings.
	(do_mve_vstr_vldr_QI): New encoding functions.
	(do_mve_vstr_vldr_RQ): Likewise.
	(do_mve_vstr_vldr_RI): Likewise.
	(do_mve_vstr_vldr): Likewise.
	* testsuite/gas/arm/mve-vldr-bad-1.d: New test.
	* testsuite/gas/arm/mve-vldr-bad-1.l: New test.
	* testsuite/gas/arm/mve-vldr-bad-1.s: New test.
	* testsuite/gas/arm/mve-vldr-bad-2.d: New test.
	* testsuite/gas/arm/mve-vldr-bad-2.l: New test.
	* testsuite/gas/arm/mve-vldr-bad-2.s: New test.
	* testsuite/gas/arm/mve-vldr-bad-3.d: New test.
	* testsuite/gas/arm/mve-vldr-bad-3.l: New test.
	* testsuite/gas/arm/mve-vldr-bad-3.s: New test.
	* testsuite/gas/arm/mve-vstr-bad-1.d: New test.
	* testsuite/gas/arm/mve-vstr-bad-1.l: New test.
	* testsuite/gas/arm/mve-vstr-bad-1.s: New test.
	* testsuite/gas/arm/mve-vstr-bad-2.d: New test.
	* testsuite/gas/arm/mve-vstr-bad-2.l: New test.
	* testsuite/gas/arm/mve-vstr-bad-2.s: New test.
	* testsuite/gas/arm/mve-vstr-bad-3.d: New test.
	* testsuite/gas/arm/mve-vstr-bad-3.l: New test.
	* testsuite/gas/arm/mve-vstr-bad-3.s: New test.