This patch enables the ACLE intrinsics calling VCX1<A>,
VCX2<A>, and VCX3<A> instructions who work with FPU/MVE
32-bit/64-bit registers. This patch also enables DImode for VFP
to support CDE with FPU.

gcc/ChangeLog:
2020-04-08  Dennis Zhang  <dennis.zhang@arm.com>
	    Matthew Malcomson <matthew.malcomson@arm.com>

	* config/arm/arm-builtins.c (CX_IMM_QUALIFIERS): New macro.
	(CX_UNARY_QUALIFIERS, CX_BINARY_QUALIFIERS): Likewise.
	(CX_TERNARY_QUALIFIERS): Likewise.
	(ARM_BUILTIN_CDE_PATTERN_START): Likewise.
	(ARM_BUILTIN_CDE_PATTERN_END): Likewise.
	(arm_init_acle_builtins): Initialize CDE builtins.
	(arm_expand_acle_builtin): Check CDE constant operands.
	* config/arm/arm.h (ARM_CDE_CONST_COPROC): New macro to set the range
	of CDE constant operand.
	* config/arm/arm.c (arm_hard_regno_mode_ok): Support DImode for
	TARGET_VFP_BASE.
	(ARM_VCDE_CONST_1, ARM_VCDE_CONST_2, ARM_VCDE_CONST_3): Likewise.
	* config/arm/arm_cde.h (__arm_vcx1_u32): New macro of ACLE interface.
	(__arm_vcx1a_u32, __arm_vcx2_u32, __arm_vcx2a_u32): Likewise.
	(__arm_vcx3_u32, __arm_vcx3a_u32, __arm_vcx1d_u64): Likewise.
	(__arm_vcx1da_u64, __arm_vcx2d_u64, __arm_vcx2da_u64): Likewise.
	(__arm_vcx3d_u64, __arm_vcx3da_u64): Likewise.
	* config/arm/arm_cde_builtins.def: New file.
	* config/arm/iterators.md (V_reg): New attribute of SI.
	* config/arm/predicates.md (const_int_coproc_operand): New.
	(const_int_vcde1_operand, const_int_vcde2_operand): New.
	(const_int_vcde3_operand): New.
	* config/arm/unspecs.md (UNSPEC_VCDE, UNSPEC_VCDEA): New.
	* config/arm/vfp.md (arm_vcx1<mode>): New entry.
	(arm_vcx1a<mode>, arm_vcx2<mode>, arm_vcx2a<mode>): Likewise.
	(arm_vcx3<mode>, arm_vcx3a<mode>): Likewise.

gcc/testsuite/ChangeLog:
2020-04-08  Dennis Zhang  <dennis.zhang@arm.com>

	* gcc.target/arm/acle/cde_v_1.c: New test.
	* gcc.target/arm/acle/cde_v_1_err.c: New test.
	* gcc.target/arm/acle/cde_v_1_mve.c: New test.