{name: "Ctz64NonZero", argLength: 1}, // same as above, but arg[0] known to be non-zero, returns 0-63
	{name: "BitLen8", argLength: 1},      // Number of bits in arg[0] (returns 0-8)
	{name: "BitLen16", argLength: 1},     // Number of bits in arg[0] (returns 0-16)
	{name: "BitLen32", argLength: 1},     // Number of bits in arg[0] (returns 0-32)
	{name: "BitLen64", argLength: 1},     // Number of bits in arg[0] (returns 0-64)

(BitLen32 x) && buildcfg.GOAMD64 <  3 => (Select0 (BSRQ (LEAQ1 <typ.UInt64> [1] (MOVLQZX <typ.UInt64> x) (MOVLQZX <typ.UInt64> x))))
(BitLen16 x) && buildcfg.GOAMD64 <  3 => (BSRL (LEAL1 <typ.UInt32> [1] (MOVWQZX <typ.UInt32> x) (MOVWQZX <typ.UInt32> x)))
(BitLen8  x) && buildcfg.GOAMD64 <  3 => (BSRL (LEAL1 <typ.UInt32> [1] (MOVBQZX <typ.UInt32> x) (MOVBQZX <typ.UInt32> x)))

		v.AddArg(v0)
		return true
	}
}
func rewriteValueAMD64_OpBitLen16(v *Value) bool {
	v_0 := v.Args[0]
	b := v.Block
	typ := &b.Func.Config.Types
	// match: (BitLen16 x)
	// cond: buildcfg.GOAMD64 < 3
	// result: (BSRL (LEAL1 <typ.UInt32> [1] (MOVWQZX <typ.UInt32> x) (MOVWQZX <typ.UInt32> x)))
	for {
		x := v_0
		if !(buildcfg.GOAMD64 < 3) {
			break
		}

	},
	{
		name:    "Ctz64NonZero",
		argLen:  1,
		generic: true,
	},
	{
		name:    "BitLen8",
		argLen:  1,
		generic: true,
	},
	{
		name:    "BitLen16",
		argLen:  1,
		generic: true,
	},
	{
		name:    "BitLen32",
		argLen:  1,
		generic: true,
	},
	{
		name:    "BitLen64",
		argLen:  1,
		generic: true,