sllOp, srlOp = ASLLW, ASRLW
		}
		shift1, shift2 := sllOp, srlOp
		if ins.as == AROR || ins.as == ARORW {
			shift1, shift2 = shift2, shift1
		}
		return []*instruction{
			&instruction{as: ASUB, rs1: REG_ZERO, rs2: ins.rs2, rd: REG_TMP},
			&instruction{as: shift2, rs1: ins.rs1, rs2: REG_TMP, rd: REG_TMP},
			&instruction{as: shift1, rs1: ins.rs1, rs2: ins.rs2, rd: ins.rd},

// the 1.18 compiler using the new types2 type checker, or pass with sub-optimal
// error(s).

// List of files that the compiler cannot errorcheck with the new typechecker (types2).
var types2Failures = setOf(
	"shift1.go",               // types2 reports two new errors which are probably not right
	"fixedbugs/issue10700.go", // types2 should give hint about ptr to interface

	case *Map:
		return "map"
	case *Chan:
		return "chan"
	default:
		return check.sprintf("%s", typ) // catch-all
	}
}

// If e != nil, it must be the shift expression; it may be nil for non-constant shifts.
func (check *Checker) shift(x, y *operand, e ast.Expr, op token.Token) {
	// TODO(gri) This function seems overly complex. Revisit.

	var xval constant.Value
	if x.mode == constant_ {

	case *Map:
		return "map"
	case *Chan:
		return "chan"
	default:
		return check.sprintf("%s", typ) // catch-all
	}
}

// If e != nil, it must be the shift expression; it may be nil for non-constant shifts.
func (check *Checker) shift(x, y *operand, e syntax.Expr, op syntax.Operator) {
	// TODO(gri) This function seems overly complex. Revisit.

	var xval constant.Value
	if x.mode == constant_ {

		case 0:
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {
					return 0, ErrIntOverflowGenerated
				}
				if iNdEx >= l {
					return 0, io.ErrUnexpectedEOF
				}
				iNdEx++
				if dAtA[iNdEx-1] < 0x80 {
					break
				}
			}
		case 1:
			iNdEx += 8
		case 2:
			var length int
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {

		case 0:
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {
					return 0, ErrIntOverflowGenerated
				}
				if iNdEx >= l {
					return 0, io.ErrUnexpectedEOF
				}
				iNdEx++
				if dAtA[iNdEx-1] < 0x80 {
					break
				}
			}
		case 1:
			iNdEx += 8
		case 2:
			var length int
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {

		case 0:
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {
					return 0, ErrIntOverflowGenerated
				}
				if iNdEx >= l {
					return 0, io.ErrUnexpectedEOF
				}
				iNdEx++
				if dAtA[iNdEx-1] < 0x80 {
					break
				}
			}
		case 1:
			iNdEx += 8
		case 2:
			var length int
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {

// Signed right shift needs to return 0/-1 if shift amount is >= width of shifted value.
// We implement this by setting the shift value to 63 (all ones) if the shift value is more than 63.
//   result = arg >> (shift >= 64 ? 63 : shift)
(Rsh(64|32)x64 x y) => (SRA(D|W) x (LOCGR {s390x.GreaterOrEqual} <y.Type> y (MOVDconst <y.Type> [63]) (CMPUconst  y [64])))

		case 0:
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {
					return 0, ErrIntOverflowGenerated
				}
				if iNdEx >= l {
					return 0, io.ErrUnexpectedEOF
				}
				iNdEx++
				if dAtA[iNdEx-1] < 0x80 {
					break
				}
			}
		case 1:
			iNdEx += 8
		case 2:
			var length int
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {

		case 0:
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {
					return 0, ErrIntOverflowGenerated
				}
				if iNdEx >= l {
					return 0, io.ErrUnexpectedEOF
				}
				iNdEx++
				if dAtA[iNdEx-1] < 0x80 {
					break
				}
			}
		case 1:
			iNdEx += 8
		case 2:
			var length int
			for shift := uint(0); ; shift += 7 {
				if shift >= 64 {