Mono.CSharp.While.DoEmit C# (CSharp) Method

		protected override void DoEmit (EmitContext ec)
		{
			if (empty) {
				expr.EmitSideEffect (ec);
				return;
			}

			Label old_begin = ec.LoopBegin;
			Label old_end = ec.LoopEnd;
			
			ec.LoopBegin = ec.DefineLabel ();
			ec.LoopEnd = ec.DefineLabel ();

			//
			// Inform whether we are infinite or not
			//
			if (expr is Constant){
				// expr is 'true', since the 'empty' case above handles the 'false' case
				ec.MarkLabel (ec.LoopBegin);
				expr.EmitSideEffect (ec);
				Statement.Emit (ec);
				ec.Emit (OpCodes.Br, ec.LoopBegin);
					
				//
				// Inform that we are infinite (ie, `we return'), only
				// if we do not `break' inside the code.
				//
				ec.MarkLabel (ec.LoopEnd);
			} else {
				Label while_loop = ec.DefineLabel ();

				ec.Emit (OpCodes.Br, ec.LoopBegin);
				ec.MarkLabel (while_loop);

				Statement.Emit (ec);
			
				ec.MarkLabel (ec.LoopBegin);
				ec.Mark (loc);

				expr.EmitBranchable (ec, while_loop, true);
				
				ec.MarkLabel (ec.LoopEnd);
			}	

			ec.LoopBegin = old_begin;
			ec.LoopEnd = old_end;
		}