protected override void EmitMarshalFieldManagedToNative()
{
// It generates the following code
//if (ManagedArg.Field != null)
//{
//
// fixed (InlineArray* pUnsafe = &NativeArg.Field)
// {
// uint index = 0u;
// while ((ulong)index < (ulong)((long)ManagedArg.Field.Length))
// {
// NativeArg.s[index] = ManagedArg.Field[(int)index];
// index += 1u;
// }
// }
//}
ILEmitter emitter = _ilCodeStreams.Emitter;
ILCodeStream codeStream = _ilCodeStreams.MarshallingCodeStream;
var nativeArrayType = NativeType as InlineArrayType;
Debug.Assert(nativeArrayType != null);
Debug.Assert(ManagedType is ArrayType);
var managedElementType = ((ArrayType)ManagedType).ElementType;
ILCodeLabel lDone = emitter.NewCodeLabel();
ILCodeLabel lRangeCheck = emitter.NewCodeLabel();
ILCodeLabel lLoopHeader = emitter.NewCodeLabel();
ILLocalVariable vIndex = emitter.NewLocal(Context.GetWellKnownType(WellKnownType.Int32));
ILLocalVariable vLength = emitter.NewLocal(Context.GetWellKnownType(WellKnownType.Int32));
ILLocalVariable vNative = emitter.NewLocal(NativeType.MakeByRefType(), isPinned: true);
// check if ManagedType == null, then return
codeStream.EmitLdArg(0);
codeStream.Emit(ILOpcode.ldfld, emitter.NewToken(_managedField));
codeStream.Emit(ILOpcode.brfalse, lDone);
codeStream.EmitLdArg(1);
codeStream.Emit(ILOpcode.ldflda, emitter.NewToken(_nativeField));
codeStream.EmitStLoc(vNative);
EmitElementCount(codeStream, MarshalDirection.Forward);
codeStream.EmitStLoc(vLength);
codeStream.EmitLdc(0);
codeStream.EmitStLoc(vIndex);
codeStream.Emit(ILOpcode.br, lRangeCheck);
codeStream.EmitLabel(lLoopHeader);
codeStream.EmitLdArg(1);
codeStream.Emit(ILOpcode.ldflda, emitter.NewToken(_nativeField));
codeStream.EmitLdLoc(vIndex);
codeStream.EmitLdArg(0);
codeStream.Emit(ILOpcode.ldfld, emitter.NewToken(_managedField));
codeStream.EmitLdLoc(vIndex);
codeStream.EmitLdElem(managedElementType);
// generate marshalling IL for the element
GetElementMarshaller(MarshalDirection.Forward)
.EmitMarshallingIL(new PInvokeILCodeStreams(_ilCodeStreams.Emitter, codeStream));
codeStream.Emit(ILOpcode.call, emitter.NewToken(
nativeArrayType.GetInlineArrayMethod(InlineArrayMethodKind.Setter)));
codeStream.EmitLdLoc(vIndex);
codeStream.EmitLdc(1);
codeStream.Emit(ILOpcode.add);
codeStream.EmitStLoc(vIndex);
codeStream.EmitLabel(lRangeCheck);
codeStream.EmitLdLoc(vIndex);
codeStream.EmitLdLoc(vLength);
codeStream.Emit(ILOpcode.blt, lLoopHeader);
codeStream.EmitLabel(lDone);
}