(CSEL  [cc] x _ flag) && ccARM64Eval(cc, flag) > 0 => x
(CSEL  [cc] _ y flag) && ccARM64Eval(cc, flag) < 0 => y
(CSEL0 [cc] x   flag) && ccARM64Eval(cc, flag) > 0 => x
(CSEL0 [cc] _   flag) && ccARM64Eval(cc, flag) < 0 => (MOVDconst [0])
(CSNEG [cc] x _ flag) && ccARM64Eval(cc, flag) > 0 => x
(CSNEG [cc] _ y flag) && ccARM64Eval(cc, flag) < 0 => (NEG y)

		return true
	}
	// match: (CSEL [cc] x _ flag)
	// cond: ccARM64Eval(cc, flag) > 0
	// result: x
	for {
		cc := auxIntToOp(v.AuxInt)
		x := v_0
		flag := v_2
		if !(ccARM64Eval(cc, flag) > 0) {
			break
		}
		v.copyOf(x)
		return true
	}
	// match: (CSEL [cc] _ y flag)
	// cond: ccARM64Eval(cc, flag) < 0
	// result: y
	for {
		cc := auxIntToOp(v.AuxInt)

	}
}

// evaluate an ARM64 op against a flags value
// that is potentially constant; return 1 for true,
// -1 for false, and 0 for not constant.
func ccARM64Eval(op Op, flags *Value) int {
	fop := flags.Op
	if fop == OpARM64InvertFlags {
		return -ccARM64Eval(op, flags.Args[0])
	}
	if fop != OpARM64FlagConstant {
		return 0
	}
	fc := flagConstant(flags.AuxInt)
	b2i := func(b bool) int {
		if b {