// cond: v.Block == z.Block
	// result: (CMPconst [0] convertPPC64OpToOpCC(z))
	for {
		if auxIntToInt64(v.AuxInt) != 0 {
			break
		}
		z := v_0
		if z.Op != OpPPC64ADD {
			break
		}
		if !(v.Block == z.Block) {
			break
		}
		v.reset(OpPPC64CMPconst)
		v.AuxInt = int64ToAuxInt(0)
		v.AddArg(convertPPC64OpToOpCC(z))
		return true
	}
	// match: (CMPconst [0] z:(AND x y))

(CMPconst [0] z:((ADD|AND|ANDN|OR|SUB|NOR|XOR) x y)) && v.Block == z.Block => (CMPconst [0] convertPPC64OpToOpCC(z))
(CMPconst [0] z:((NEG|CNTLZD|RLDICL) x)) && v.Block == z.Block => (CMPconst [0] convertPPC64OpToOpCC(z))
// Note: ADDCCconst only assembles to 1 instruction for int16 constants.
(CMPconst [0] z:(ADDconst [c] x)) && int64(int16(c)) == c && v.Block == z.Block => (CMPconst [0] convertPPC64OpToOpCC(z))

// of this conversion is:
// a' = (ADDCC x y)
// a  = (Select0 a')
// b  = (CMPconst [0] a)
// c  = (OR a z)
//
// Which makes it trivial to rewrite b using a lowering rule.
func convertPPC64OpToOpCC(op *Value) *Value {
	ccOpMap := map[Op]Op{
		OpPPC64ADD:      OpPPC64ADDCC,
		OpPPC64ADDconst: OpPPC64ADDCCconst,
		OpPPC64AND:      OpPPC64ANDCC,
		OpPPC64ANDconst: OpPPC64ANDCCconst,