public InteropIntrinsicAttribute(InteropIntrinsicKind intrinsicKind)
{
IntrinsicKind = intrinsicKind;
}
/// <summary>
/// Handles general interop operations.
/// </summary>
/// <param name="context">The current invocation context.</param>
/// <param name="kind">The kind of the interop intrinsic.</param>
/// <returns>The resulting value.</returns>
protected virtual Value?MakeInterop(InvocationContext context, InteropIntrinsicKind kind)
{
var compilationContext = context.CompilationContext;
var args = context.GetArgs();
var genericArgs = context.GetMethodGenericArguments();
var type = genericArgs.Length > 0 ? genericArgs[0] : null;
var llvmType = context.Unit.GetType(type);
var builder = context.Builder;
var int32Type = context.LLVMContext.Int32Type;
switch (kind)
{
case InteropIntrinsicKind.DestroyStructure:
return(new Value(type, BuildStore(builder, args[0].LLVMValue, ConstNull(llvmType))));
case InteropIntrinsicKind.SizeOf:
return(new Value(typeof(int), BuildTruncOrBitCast(builder, SizeOf(llvmType), int32Type, string.Empty)));
case InteropIntrinsicKind.OffsetOf:
{
if (type.IsPrimitive)
{
throw compilationContext.GetNotSupportedException(
ErrorMessages.CannotTakeFieldOffsetOfPrimitiveType, type);
}
// Argument is a GEP
var testVal = args[0].LLVMValue;
var gepSource = GetOperand(testVal, 0);
// First argument is the string const
var stringConst = GetOperand(gepSource, 0);
var stringPtr = GetAsString(stringConst, out IntPtr size);
var sizeVal = size.ToInt32();
if (sizeVal < 2)
{
throw compilationContext.GetNotSupportedException(
ErrorMessages.CannotFindFieldOfType, string.Empty, type);
}
var fieldName = Marshal.PtrToStringAnsi(stringPtr, Math.Max(sizeVal - 1, 0));
var mappedType = context.Unit.GetObjectType(type);
var info = mappedType.ManagedType.GetField(fieldName);
if (info == null || !mappedType.TryResolveOffset(info, out int offset))
{
throw compilationContext.GetNotSupportedException(
ErrorMessages.CannotFindFieldOfType, fieldName, type);
}
var index = ConstInt(int32Type, offset, false);
var offsetPointer = BuildInBoundsGEP(
builder,
ConstPointerNull(llvmType),
out index,
1,
string.Empty);
var intOffset = BuildPtrToInt(builder, offsetPointer, int32Type, string.Empty);
return(new Value(typeof(int), intOffset));
}
default:
throw compilationContext.GetNotSupportedException(
ErrorMessages.NotSupportedIntrinsic, kind);
}
}
