cv = constant.BinaryOp(cv, token.AND, constant.MakeUint64(1<<bits-1))
			if t.IsSigned() && constant.Compare(cv, token.GEQ, constant.MakeUint64(1<<(bits-1))) {
				cv = constant.BinaryOp(cv, token.OR, constant.MakeInt64(-1<<(bits-1)))
			}
		}
	}
	c = ir.NewConstExpr(cv, c)
	c.SetType(t)
	return c, true
}

func addStr(n *ir.AddStringExpr) ir.Node {
	// Merge adjacent constants in the argument list.

func (r *rewriter) intConst(c int) *syntax.BasicLit {
	lit := &syntax.BasicLit{
		Value: fmt.Sprint(c),
		Kind:  syntax.IntLit,
	}
	tv := syntax.TypeAndValue{Type: r.int.Type(), Value: constant.MakeInt64(int64(c))}
	tv.SetIsValue()
	lit.SetTypeInfo(tv)
	return lit
}

func (r *rewriter) stateConst(s abi.RF_State) *syntax.BasicLit {
	return r.intConst(int(s))
}