private static bool TryEmit(this LambdaExpression expression, ILGenerator generator, CompilerContext context, params ParameterExpression[] parameters)
{
var lambdaClosureIndex = context.StoredExpressions.GetIndex(expression);
if (lambdaClosureIndex == -1)
{
return(false);
}
var lambdaIndex = context.NestedLambdas.GetIndex(expression);
if (lambdaIndex == -1)
{
return(false);
}
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldfld, context.Target.Fields[lambdaClosureIndex]);
if (context.HasCapturedVariablesArgument)
{
if (!context.IsNestedLambda)
{
generator.Emit(OpCodes.Ldloc, context.CapturedArgumentsHolderVariable);
}
else
{
generator.Emit(OpCodes.Ldarg_1);
}
}
var lambda = context.NestedLambdas[lambdaIndex];
var lambdaExpression = lambda.Key;
var variables = lambda.Value;
var nestedParameters = lambdaExpression.Parameters.CastToArray();
var nestedContext = context.CreateNew(variables, true);
var method = nestedContext.HasCapturedVariablesArgument
? new DynamicMethod(string.Empty, lambdaExpression.ReturnType, nestedContext.HasCapturedVariablesArgument
? new[] { nestedContext.Target.TargetType, nestedContext.CapturedArgumentsHolder.TargetType }.Append(nestedParameters.GetTypes())
: nestedContext.Target.TargetType.Append(parameters.GetTypes()), nestedContext.Target.TargetType, true)
: new DynamicMethod(string.Empty, lambdaExpression.ReturnType, nestedContext.Target.TargetType.Append(nestedParameters.GetTypes()), nestedContext.Target.TargetType, true);
var nestedGenerator = method.GetILGenerator();
if (variables.Length > 0)
{
nestedContext.LocalBuilders = BuildLocals(variables, nestedGenerator);
}
if (nestedContext.HasCapturedVariablesArgument)
{
nestedGenerator.CopyParametersToCapturedArgumentsIfAny(nestedContext, nestedParameters);
}
if (!lambdaExpression.Body.TryEmit(nestedGenerator, nestedContext, nestedParameters))
{
return(false);
}
nestedGenerator.Emit(OpCodes.Ret);
if (nestedContext.HasCapturedVariablesArgument)
{
var delegateArgs = nestedContext.CapturedArgumentsHolder.TargetType
.Append(nestedParameters.GetTypes())
.Append(lambdaExpression.ReturnType);
var resultDelegate = method.CreateDelegate(Utils.MapDelegateType(delegateArgs),
nestedContext.Target.Target);
nestedContext.Target.Fields[lambdaClosureIndex].SetValue(nestedContext.Target.Target, resultDelegate);
if (nestedContext.HasCapturedVariablesArgument)
{
generator.EmitMethod(Utils.GetMapperMethodInfo(delegateArgs));
}
}
else
{
var resultDelegate = method.CreateDelegate(lambdaExpression.Type, nestedContext.Target.Target);
nestedContext.Target.Fields[lambdaClosureIndex].SetValue(nestedContext.Target.Target, resultDelegate);
}
return(true);
}
private static bool TryEmit(this LambdaExpression expression, ILGenerator generator, CompilerContext context)
{
var lambdaIndex = context.NestedLambdas.IndexAndValueOf(expression, out var lambda);
if (lambdaIndex == -1)
{
return(false);
}
var lambdaClosureIndex = lambdaIndex + (context.Target.Constants.Length - context.NestedLambdas.Length);
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldfld, Closure.ConstantsField);
generator.EmitInteger(lambdaClosureIndex);
generator.Emit(OpCodes.Ldelem_Ref);
if (lambda.UsesCapturedArgument)
{
if (!context.IsNestedLambda)
{
generator.Emit(OpCodes.Ldloc, context.CapturedArgumentsHolderVariable);
}
else
{
generator.Emit(OpCodes.Ldarg_1);
}
}
var variables = lambda.ParameterExpressions;
var nestedParameters = expression.Parameters.CastToArray();
var nestedContext = context.CreateNew(variables, true, lambda.UsesCapturedArgument);
var method = new DynamicMethod(string.Empty,
expression.ReturnType,
nestedContext.HasCapturedVariablesArgument
? new[] { Utils.ClosureType, Utils.ObjectArrayType }.Append(nestedParameters.GetTypes())
: Utils.ClosureType.Append(nestedParameters.GetTypes()),
Utils.ClosureType,
true);
var nestedGenerator = method.GetILGenerator();
if (variables.Length > 0)
{
nestedContext.LocalBuilders = variables.BuildLocals(nestedGenerator);
}
if (nestedContext.HasCapturedVariablesArgument)
{
nestedGenerator.CopyParametersToCapturedArgumentsIfAny(nestedContext, nestedParameters);
}
if (!expression.Body.TryEmit(nestedGenerator, nestedContext, nestedParameters))
{
return(false);
}
nestedGenerator.Emit(OpCodes.Ret);
if (nestedContext.HasCapturedVariablesArgument)
{
var delegateArgs = Utils.ObjectArrayType
.Append(nestedParameters.GetTypes())
.Append(expression.ReturnType);
var resultDelegate = method.CreateDelegate(Utils.MapDelegateType(delegateArgs),
nestedContext.Target);
nestedContext.Target.Constants[lambdaClosureIndex] = resultDelegate;
if (nestedContext.HasCapturedVariablesArgument)
{
generator.EmitMethod(Utils.GetPartialApplicationMethodInfo(delegateArgs));
}
}
else
{
var resultDelegate = method.CreateDelegate(expression.Type, nestedContext.Target);
nestedContext.Target.Constants[lambdaClosureIndex] = resultDelegate;
}
return(true);
}