y += x
	return (y-1)&y == 0
}

// isARM64addcon reports whether x can be encoded as the immediate value in an ADD or SUB instruction.
func isARM64addcon(v int64) bool {
	/* uimm12 or uimm24? */
	if v < 0 {
		return false
	}
	if (v & 0xFFF) == 0 {
		v >>= 12
	}
	return v <= 0xFFF
}

// setPos sets the position of v to pos, then returns true.

		[6]*argField{ap_VecSReg_47_47_38_42, ap_ImmUnsigned_46_46, ap_ImmUnsigned_16_31_48_63}},
	{XXSPLTIDP, 0xfff00000fc1e0000, 0x500000080040000, 0xf000000000000, // VSX Vector Splat Immediate Double-Precision 8RR:D-form (xxspltidp XT,IMM32)
		[6]*argField{ap_VecSReg_47_47_38_42, ap_ImmUnsigned_16_31_48_63}},