type Point struct {
	X, Y int
}

// invertLessThanNoov checks (LessThanNoov (InvertFlags x)) is lowered as
// CMP, CSET, CSEL instruction sequence. InvertFlags are only generated under
// certain conditions, see canonLessThan, so if the code below does not
// generate an InvertFlags OP, this check may fail.
func invertLessThanNoov(p1, p2, p3 Point) bool {
	// arm64:`CMP`,`CSET`,`CSEL`
	return (p1.X-p3.X)*(p2.Y-p3.Y)-(p2.X-p3.X)*(p1.Y-p3.Y) < 0

// A shift is bounded if it is shifting by less than the width of the shifted value.
func shiftIsBounded(v *Value) bool {
	return v.AuxInt != 0
}

// canonLessThan returns whether x is "ordered" less than y, for purposes of normalizing
// generated code as much as possible.
func canonLessThan(x, y *Value) bool {
	if x.Op != y.Op {
		return x.Op < y.Op
	}
	if !x.Pos.SameFileAndLine(y.Pos) {
		return x.Pos.Before(y.Pos)
	}

		v0.AuxInt = int64ToAuxInt(c)
		v0.AddArg(y)
		v.AddArg(v0)
		return true
	}
	// match: (CMP x y)
	// cond: canonLessThan(x,y)
	// result: (InvertFlags (CMP y x))
	for {
		x := v_0
		y := v_1
		if !(canonLessThan(x, y)) {
			break
		}
		v.reset(OpPPC64InvertFlags)
		v0 := b.NewValue0(v.Pos, OpPPC64CMP, types.TypeFlags)
		v0.AddArg2(y, x)
		v.AddArg(v0)

		v0.AuxInt = int8ToAuxInt(int8(c))
		v0.AddArg(x)
		v.AddArg(v0)
		return true
	}
	// match: (CMPB x y)
	// cond: canonLessThan(x,y)
	// result: (InvertFlags (CMPB y x))
	for {
		x := v_0
		y := v_1
		if !(canonLessThan(x, y)) {
			break
		}
		v.reset(Op386InvertFlags)
		v0 := b.NewValue0(v.Pos, Op386CMPB, types.TypeFlags)
		v0.AddArg2(y, x)
		v.AddArg(v0)

		v0.AuxInt = int32ToAuxInt(int32(c))
		v0.AddArg(x)
		v.AddArg(v0)
		return true
	}
	// match: (CMP x y)
	// cond: canonLessThan(x,y)
	// result: (InvertFlags (CMP y x))
	for {
		x := v_0
		y := v_1
		if !(canonLessThan(x, y)) {
			break
		}
		v.reset(OpS390XInvertFlags)
		v0 := b.NewValue0(v.Pos, OpS390XCMP, types.TypeFlags)
		v0.AddArg2(y, x)
		v.AddArg(v0)

(CMPWU (MOVDconst [c]) y) && isU16Bit(c) => (InvertFlags (CMPWUconst y [int32(c)]))

// Canonicalize the order of arguments to comparisons - helps with CSE.
((CMP|CMPW|CMPU|CMPWU) x y) && canonLessThan(x,y) => (InvertFlags ((CMP|CMPW|CMPU|CMPWU) y x))

// n is always a zero-extended uint16 value, so n & z is always a non-negative 32 or 64 bit value.
// Rewrite to a cmp int64(0) to lower into ANDCCconst in the latelower pass.

  => (RISBGZ x {s390x.NewRotateParams(r.Start, r.Start, -r.Start&63)})

// Canonicalize the order of arguments to comparisons - helps with CSE.
((CMP|CMPW|CMPU|CMPWU) x y) && canonLessThan(x,y) => (InvertFlags ((CMP|CMPW|CMPU|CMPWU) y x))

// Use sign/zero extend instead of RISBGZ.
(RISBGZ x {r}) && r == s390x.NewRotateParams(56, 63, 0) => (MOVBZreg x)

		v0.AuxInt = int8ToAuxInt(int8(c))
		v0.AddArg(x)
		v.AddArg(v0)
		return true
	}
	// match: (CMPB x y)
	// cond: canonLessThan(x,y)
	// result: (InvertFlags (CMPB y x))
	for {
		x := v_0
		y := v_1
		if !(canonLessThan(x, y)) {
			break
		}
		v.reset(OpAMD64InvertFlags)
		v0 := b.NewValue0(v.Pos, OpAMD64CMPB, types.TypeFlags)
		v0.AddArg2(y, x)
		v.AddArg(v0)

(CMPB x (MOVLconst [c])) => (CMPBconst x [int8(c)])
(CMPB (MOVLconst [c]) x) => (InvertFlags (CMPBconst x [int8(c)]))

// Canonicalize the order of arguments to comparisons - helps with CSE.
(CMP(Q|L|W|B) x y) && canonLessThan(x,y) => (InvertFlags (CMP(Q|L|W|B) y x))

// Using MOVZX instead of AND is cheaper.
(AND(Q|L)const [  0xFF] x) => (MOVBQZX x)
(AND(Q|L)const [0xFFFF] x) => (MOVWQZX x)

(ADDSflags x (MOVDconst [c]))  => (ADDSconstflags [c] x)

(ADDconst [c] y) && c < 0 => (SUBconst [-c] y)

// Canonicalize the order of arguments to comparisons - helps with CSE.
((CMP|CMPW) x y) && canonLessThan(x,y) => (InvertFlags ((CMP|CMPW) y x))

// mul-neg => mneg
(NEG  (MUL  x y)) => (MNEG  x y)
(NEG  (MULW x y)) && v.Type.Size() <= 4 => (MNEGW x y)
(MUL  (NEG  x) y) => (MNEG  x y)