"istio.io/istio/pkg/config/constants"
	"istio.io/istio/pkg/config/host"
	"istio.io/istio/pkg/config/protocol"
	"istio.io/istio/pkg/log"
	"istio.io/istio/pkg/monitoring"
	"istio.io/istio/pkg/proto"
	secconst "istio.io/istio/pkg/security"
	"istio.io/istio/pkg/slices"
	netutil "istio.io/istio/pkg/util/net"
	"istio.io/istio/pkg/util/sets"
	"istio.io/istio/pkg/wellknown"
)

const (
	NoConflict = iota

(ADDconst [c] (SUBconst [d] x)) => (ADDconst [c-d] x)
(ADDconst [c] (RSBconst [d] x)) => (RSBconst [c+d] x)
(ADCconst [c] (ADDconst [d] x) flags) => (ADCconst [c+d] x flags)
(ADCconst [c] (SUBconst [d] x) flags) => (ADCconst [c-d] x flags)
(SUBconst [c] (MOVWconst [d])) => (MOVWconst [d-c])
(SUBconst [c] (SUBconst [d] x)) => (ADDconst [-c-d] x)
(SUBconst [c] (ADDconst [d] x)) => (ADDconst [-c+d] x)

// Match (x >> c) << d to 'rotate then insert selected bits [into zero]'.
(SLDconst (SRDconst x [c]) [d]) => (RISBGZ x {s390x.NewRotateParams(uint8(max8(0, int8(c-d))), 63-d, uint8(int8(d-c)&63))})

// Match (x << c) >> d to 'rotate then insert selected bits [into zero]'.
(SRDconst (SLDconst x [c]) [d]) => (RISBGZ x {s390x.NewRotateParams(d, uint8(min8(63, int8(63-c+d))), uint8(int8(c-d)&63))})

(MOVBZreg (SRDconst [c] x)) && c>=56 => (SRDconst [c] x)
(MOVBreg (SRDconst [c] x)) && c>56 => (SRDconst [c] x)
(MOVBreg (SRDconst [c] x)) && c==56 => (SRADconst [c] x)
(MOVBreg (SRADconst [c] x)) && c>=56 => (SRADconst [c] x)
(MOVBZreg (SRWconst [c] x)) && c>=24 => (SRWconst [c] x)
(MOVBreg (SRWconst [c] x)) && c>24 => (SRWconst [c] x)
(MOVBreg (SRWconst [c] x)) && c==24 => (SRAWconst [c] x)

				goto Error
			}
		}
		x.setConst(e.Kind, e.Value)
		if x.mode == invalid {
			// The parser already establishes syntactic correctness.
			// If we reach here it's because of number under-/overflow.
			// TODO(gri) setConst (and in turn the go/constant package)
			// should return an error describing the issue.

		{name: "SLW", argLength: 2, reg: sh21, asm: "SLW"},                    // arg0 << arg1, shift amount is mod 64
		{name: "SLDconst", argLength: 1, reg: gp11, asm: "SLD", aux: "UInt8"}, // arg0 << auxint, shift amount 0-63
		{name: "SLWconst", argLength: 1, reg: gp11, asm: "SLW", aux: "UInt8"}, // arg0 << auxint, shift amount 0-31

				goto Error
			}
		}
		x.setConst(e.Kind, e.Value)
		if x.mode == invalid {
			// The parser already establishes syntactic correctness.
			// If we reach here it's because of number under-/overflow.
			// TODO(gri) setConst (and in turn the go/constant package)
			// should return an error describing the issue.

		{name: "SLLconst", argLength: 1, reg: gp11, asm: "LSL", aux: "Int64"},     // arg0 << auxInt, auxInt should be in the range 0 to 63.
		{name: "SRL", argLength: 2, reg: gp21, asm: "LSR"},                        // arg0 >> arg1, unsigned, shift amount is mod 64

					n.Kind = "iconst"
					n.Const = n.Define
				}
			} else if n.Define[0] == '"' {
				if _, err := parser.ParseExpr(n.Define); err == nil {
					n.Kind = "sconst"
					n.Const = n.Define
				}
			}

			if n.IsConst() {
				continue
			}
		}

		// If this is a struct, union, or enum type name, no need to guess the kind.

			p.AddRestSourceReg(ppc64.REG_R0)
		}
		// AuxInt values 4,5,6 implemented with reverse operand order from 0,1,2
		if v.AuxInt > 3 {
			p.Reg, p.GetFrom3().Reg = p.GetFrom3().Reg, p.Reg
		}
		p.From.SetConst(v.AuxInt & 3)

	case ssa.OpPPC64SETBC, ssa.OpPPC64SETBCR:
		p := s.Prog(v.Op.Asm())
		p.To.Type = obj.TYPE_REG
		p.To.Reg = v.Reg()
		p.From.Type = obj.TYPE_REG