C# - 5395
Lets emit cil code for addition using a dynamic method. Actually I emit code, which in turns emits code to call integer addition. The function Add()
below builds a dynamic method, which when run builds a dynamic method to call integer addition.
using System;
using System.Reflection.Emit;
namespace JA
{
class Program
{
static void Main(string[] args)
{
int z=Add(1, 2);
// z = 3
}
// Emit MSIL to emit MSIL
public static int Add(int x, int y)
{
Type delegate_type=typeof(Func<int, int, int>);
DynamicMethod method=new DynamicMethod(typeof(int).ToString()+".op_Addition",
typeof(int),
new Type[] { typeof(int), typeof(int) }, typeof(Program));
ILGenerator generator=method.GetILGenerator();
LocalBuilder method1=generator.DeclareLocal(typeof(DynamicMethod));
LocalBuilder generator1=generator.DeclareLocal(typeof(ILGenerator));
LocalBuilder add1=generator.DeclareLocal(typeof(Func<int, int, int>));
LocalBuilder args1=generator.DeclareLocal(typeof(Type[]));
generator.Emit(OpCodes.Ldtoken, typeof(int));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(object).GetMethod("ToString",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Instance));
generator.Emit(OpCodes.Ldstr, ".op_Addition");
generator.Emit(OpCodes.Call,
typeof(string).GetMethod("Concat",
new Type[] { typeof(string), typeof(string) }));
generator.Emit(OpCodes.Ldtoken, typeof(int));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Ldc_I4, 2);
generator.Emit(OpCodes.Newarr, typeof(Type));
generator.Emit(OpCodes.Stloc_3);
generator.Emit(OpCodes.Ldloc_3);
generator.Emit(OpCodes.Ldc_I4, 0);
generator.Emit(OpCodes.Ldtoken, typeof(int));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Stelem_Ref);
generator.Emit(OpCodes.Ldloc_3);
generator.Emit(OpCodes.Ldc_I4, 1);
generator.Emit(OpCodes.Ldtoken, typeof(int));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Stelem_Ref);
generator.Emit(OpCodes.Ldloc_3);
generator.Emit(OpCodes.Ldtoken, typeof(Program));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Newobj,
typeof(DynamicMethod).GetConstructor(
new Type[] { typeof(string), typeof(Type), typeof(Type[]), typeof(Type) }));
generator.Emit(OpCodes.Stloc_0);
generator.Emit(OpCodes.Ldloc_0);
generator.Emit(OpCodes.Callvirt,
typeof(DynamicMethod).GetMethod("GetILGenerator",
Type.EmptyTypes));
generator.Emit(OpCodes.Stloc_1);
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldtoken, typeof(int));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("DeclareLocal",
new Type[] { typeof(Type) }));
generator.Emit(OpCodes.Pop);
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldsfld,
typeof(OpCodes).GetField("Ldarg_0",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldsfld,
typeof(OpCodes).GetField("Ldarg_1",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldsfld,
typeof(OpCodes).GetField("Add",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldsfld,
typeof(OpCodes).GetField("Stloc_0",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldsfld,
typeof(OpCodes).GetField("Ldloc_0",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
generator.Emit(OpCodes.Ldloc_1);
generator.Emit(OpCodes.Ldsfld,
typeof(OpCodes).GetField("Ret",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(ILGenerator).GetMethod("Emit", new Type[] { typeof(OpCode) }));
generator.Emit(OpCodes.Ldloc_0);
generator.Emit(OpCodes.Ldtoken, typeof(Func<int, int, int>));
generator.Emit(OpCodes.Call,
typeof(Type).GetMethod("GetTypeFromHandle",
System.Reflection.BindingFlags.Public|
System.Reflection.BindingFlags.Static));
generator.Emit(OpCodes.Callvirt,
typeof(DynamicMethod).GetMethod("CreateDelegate",
new Type[] { typeof(Type) }));
generator.Emit(OpCodes.Isinst, typeof(Func<int, int, int>));
generator.Emit(OpCodes.Stloc_2);
generator.Emit(OpCodes.Ldloc_2);
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldarg_1);
generator.Emit(OpCodes.Callvirt,
typeof(Func<int, int, int>).GetMethod("Invoke",
System.Reflection.BindingFlags.Public|System.Reflection.BindingFlags.Instance));
generator.Emit(OpCodes.Ret);
Func<int, int, int> add2=method.CreateDelegate(typeof(Func<int, int, int>)) as Func<int, int, int>;
return add2(x, y);
}
}
}
2What is the range of the input numbers (maximum and minimum)? Is the program expected to work with integers or floats? Is it expected to add negative numbers? Is there any specific input format? (For example, number system? i.e. decimal/binary etc) – user12205 – 2014-03-04T22:55:34.180
3Does
a + b - b + b...
count? It would be infinite – phuclv – 2014-03-05T07:29:37.4331The longest algorithm to add two numbers is (quite trivially) provably infinite. For this problem, the winner should be the most creative and circuitous (which is a challenge) rather than simply the longest (which is not). – J... – 2014-03-05T11:09:41.093
Should we not count any spaces and newlines, or only those not required for the program for function? I'd say the latter would be saner. – nyuszika7h – 2014-03-05T15:09:15.593
1
@LưuVĩnhPhúc If you make that infinite, I think that equates to
– Tim S. – 2014-03-05T21:05:10.347a + b/2
, nota + b
(it's similar to Grandi's series).@TimS. Do it with an even number of b, not arbitrary number – phuclv – 2014-03-05T23:53:16.410
@TimS. It is a divergent series, it *does NOT equate* to anything if you actually make that an infinite sum. – user80551 – 2014-03-06T13:36:53.673
Do you want 100% code coverage? – ja72 – 2014-03-07T04:10:42.240
@user80551 there are several ways to define infinite sums. Many of them actually manage to assign a sum to the infinite series
1-1+1-1+1...
and that sum is1/2
– ypercubeᵀᴹ – 2014-03-08T03:38:31.503To make this more interesting, You should make it a rule that the length of the code are counted after compressed using, say Gzip our something like that. – Lie Ryan – 2014-03-08T13:46:22.670
@TheDoctor Did Mukul Kumar win this challenge? I'm new to this part of SE and wanted some clarification for Comintern's response and whether or not he failed to follow the rules. – les – 2014-04-07T01:51:13.900