boo-lang /src/Boo.Lang/Runtime/MethodDispatcherEmitter.cs

Language C# Lines 171
MD5 Hash 295f7d1fa4eb19c2862d37ec70ea8da7 Estimated Cost $3,069 (why?)
Repository https://github.com/boo/boo-lang.git View Raw File View Project SPDX
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
#region license
// Copyright (c) 2004, 2007 Rodrigo B. de Oliveira (rbo@acm.org)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
//	 * Redistributions of source code must retain the above copyright notice,
//	 this list of conditions and the following disclaimer.
//	 * Redistributions in binary form must reproduce the above copyright notice,
//	 this list of conditions and the following disclaimer in the documentation
//	 and/or other materials provided with the distribution.
//	 * Neither the name of Rodrigo B. de Oliveira nor the names of its
//	 contributors may be used to endorse or promote products derived from this
//	 software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#endregion

using System;
using System.Reflection;
using System.Reflection.Emit;

namespace Boo.Lang.Runtime
{
	public delegate object Dispatcher(object target, object[] args);

	public class MethodDispatcherEmitter : DispatcherEmitter
	{
		protected readonly CandidateMethod _found;
		protected readonly Type[] _argumentTypes;

		public MethodDispatcherEmitter(CandidateMethod found, params  Type[] argumentTypes) : this(found.Method.DeclaringType, found, argumentTypes)
		{	
		}

		public MethodDispatcherEmitter(Type owner, CandidateMethod found, Type[] argumentTypes) : base(owner, found.Method.Name + "$" + Builtins.join(argumentTypes, "$"))
		{
			_found = found;
			_argumentTypes = argumentTypes;
		}

		protected override void EmitMethodBody()
		{
			EmitInvocation();
			EmitMethodReturn();
		}

		protected void EmitInvocation()
		{
			EmitLoadTargetObject();
			EmitMethodArguments();
			EmitMethodCall();
		}

		protected void EmitMethodCall()
		{
			_il.Emit(_found.Method.IsStatic ? OpCodes.Call : OpCodes.Callvirt, _found.Method);
		}

		protected void EmitMethodArguments()
		{
			EmitFixedMethodArguments();
			if (_found.VarArgs) EmitVarArgsMethodArguments();
		}

		private void EmitFixedMethodArguments()
		{
			int offset = FixedArgumentOffset;
			int count = MinimumArgumentCount();
			for (int i = 0; i < count; ++i)
			{
				Type paramType = _found.GetParameterType(i + offset);
				EmitMethodArgument(i, paramType);
			}
		}

		protected virtual int FixedArgumentOffset
		{
			get { return 0; }
		}

		private void EmitVarArgsMethodArguments()
		{
			int varArgCount = _argumentTypes.Length - MinimumArgumentCount();
			Type varArgType = _found.VarArgsParameterType;
			OpCode storeOpCode = GetStoreElementOpCode(varArgType);
			_il.Emit(OpCodes.Ldc_I4, varArgCount);
			_il.Emit(OpCodes.Newarr, varArgType);
			for (int i = 0; i < varArgCount; ++i)
			{
				Dup();
				_il.Emit(OpCodes.Ldc_I4, i);
				if (IsStobj(storeOpCode))
				{
					_il.Emit(OpCodes.Ldelema, varArgType);
					EmitMethodArgument(MinimumArgumentCount() + i, varArgType);
					_il.Emit(storeOpCode, varArgType);
				}
				else
				{
					EmitMethodArgument(MinimumArgumentCount() + i, varArgType);
					_il.Emit(storeOpCode);
				}
			}
		}

		private int MinimumArgumentCount()
		{
			return _found.MinimumArgumentCount - FixedArgumentOffset;
		}

		static OpCode GetStoreElementOpCode(Type type)
		{
			if (type.IsValueType)
			{
				if (type.IsEnum) return OpCodes.Stelem_I4;

				switch (Type.GetTypeCode(type))
				{
					case TypeCode.Byte:
						return OpCodes.Stelem_I1;
					case TypeCode.Int16:
						return OpCodes.Stelem_I2;
					case TypeCode.Int32:
						return OpCodes.Stelem_I4;
					case TypeCode.Int64:
						return OpCodes.Stelem_I8;
					case TypeCode.Single:
						return OpCodes.Stelem_R4;
					case TypeCode.Double:
						return OpCodes.Stelem_R8;
				}
				return OpCodes.Stobj;
			}
			return OpCodes.Stelem_Ref;
		}

		protected void EmitMethodArgument(int argumentIndex, Type expectedType)
		{
			EmitArgArrayElement(argumentIndex);
			EmitCoercion(argumentIndex, expectedType, _found.ArgumentScores[argumentIndex]);
		}

		private void EmitCoercion(int argumentIndex, Type expectedType, int score)
		{
			EmitCoercion(_argumentTypes[argumentIndex], expectedType, score);
		}

		protected virtual void EmitLoadTargetObject()
		{
			if (_found.Method.IsStatic) return;
			EmitLoadTargetObject(_found.Method.DeclaringType);
		}

		private void EmitMethodReturn()
		{
			EmitReturn(_found.Method.ReturnType);
		}
	}
}
Back to Top