private InterpreterContext InterpretBodyImpl(uint callStackDepth, List <Variable> locals)
{
var context = new InterpreterContext(Module, ReturnTypes, locals, Module.Policy, callStackDepth + 1);
var interpreter = Module.Interpreter;
foreach (var instruction in body.BodyInstructions)
{
interpreter.Interpret(instruction, context);
if (context.BreakRequested)
{
// Functions can use a break to return. This acts exactly like
// a regular return.
OperatorImpls.Return(context);
break;
}
}
context.Return();
return(context);
}
/// <summary>
/// Invokes this function with the given argument list.
/// </summary>
/// <param name="Arguments">The list of arguments for this function's parameters.</param>
/// <returns>The list of return values.</returns>
public override IReadOnlyList <object> Invoke(IReadOnlyList <object> Arguments)
{
var locals = new List <Variable>();
// Check argument types and create parameter variables.
if (Signature.ParameterTypes.Count != Arguments.Count)
{
throw new WasmException(
"Function arity mismatch: function has " + Signature.ParameterTypes.Count +
" parameters and is given " + Arguments.Count + " arguments.");
}
// Turn each argument into a variable.
for (int i = 0; i < Signature.ParameterTypes.Count; i++)
{
locals.Add(Variable.Create <object>(Signature.ParameterTypes[i], true, Arguments[i]));
}
// Turn each local into a variable.
foreach (var localEntry in body.Locals)
{
for (int i = 0; i < localEntry.LocalCount; i++)
{
locals.Add(Variable.CreateDefault(localEntry.LocalType, true));
}
}
// Interpret the function body.
var context = new InterpreterContext(Module, locals);
var interpreter = Module.Interpreter;
foreach (var instruction in body.BodyInstructions)
{
interpreter.Interpret(instruction, context);
}
context.Return();
// Check return types.
var retVals = context.ReturnValues;
if (retVals.Count != Signature.ReturnTypes.Count)
{
throw new WasmException(
"Return value arity mismatch: function expects " + Signature.ReturnTypes.Count +
" return values but is given " + retVals.Count + " return values.");
}
for (int i = 0; i < retVals.Count; i++)
{
if (!Variable.IsInstanceOf <object>(retVals[i], Signature.ReturnTypes[i]))
{
throw new WasmException(
"Return type mismatch: function has return type '" +
((object)Signature.ReturnTypes[i]).ToString() +
" but is given a return value of type '" +
retVals[i].GetType().Name + "'.");
}
}
return(retVals);
}
