return ((x << 5) & (0xfff << 5)) << 2
}

// ubfx
// merge shifts into ubfx: (x<<lc)>>rc && lc<rc
func ubfx1(x uint64) uint64 {
	// arm64:"UBFX\t[$]1, R[0-9]+, [$]62",-"LSL",-"LSR"
	// s390x:"RISBGZ\t[$]2, [$]63, [$]63,",-"SLD",-"SRD"
	return (x << 1) >> 2
}

// merge shift and zero-extension into ubfx.
func ubfx2(x uint32) uint64 {
	return uint64(x >> 15) // arm64:"UBFX\t[$]15, R[0-9]+, [$]17",-"LSR"
}

	"SWPW",
	"SXTB",
	"SXTBW",
	"SXTH",
	"SXTHW",
	"SXTW",
	"SYS",
	"SYSL",
	"TBNZ",
	"TBZ",
	"TLBI",
	"TST",
	"TSTW",
	"UBFIZ",
	"UBFIZW",
	"UBFM",
	"UBFMW",
	"UBFX",
	"UBFXW",
	"UCVTFD",
	"UCVTFS",
	"UCVTFWD",
	"UCVTFWS",
	"UDIV",
	"UDIVW",
	"UMADDL",
	"UMNEGL",
	"UMSUBL",
	"UMULH",
	"UMULL",
	"UREM",
	"UREMW",
	"UXTB",

Examples:

	FMADDD F30, F20, F3, F29    <=>    fmadd d29, d3, d30, d20
	FNMSUBS F7, F25, F7, F22    <=>    fnmsub s22, s7, s7, s25

(4) BFI, BFXIL, SBFIZ, SBFX, UBFIZ, UBFX $<lsb>, <Rn>, $<width>, <Rd>

Examples:

	BFIW $16, R20, $6, R0      <=>    bfi w0, w20, #16, #6
	UBFIZ $34, R26, $5, R20    <=>    ubfiz x20, x26, #34, #5