private static void EncodeTypeLayout(ObjectDataSignatureBuilder dataBuilder, TypeDesc type)
{
Debug.Assert(type.IsValueType);
MetadataType defType = (MetadataType)type;
int pointerSize = type.Context.Target.PointerSize;
int size = defType.InstanceFieldSize.AsInt;
int alignment = GetClassAlignmentRequirement(defType);
ReadyToRunTypeLayoutFlags flags = ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_Alignment | ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_GCLayout;
if (alignment == pointerSize)
{
flags |= ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_Alignment_Native;
}
if (!defType.ContainsGCPointers)
{
flags |= ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_GCLayout_Empty;
}
if (defType.IsHomogeneousAggregate)
{
flags |= ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_HFA;
}
dataBuilder.EmitUInt((uint)flags);
dataBuilder.EmitUInt((uint)size);
if (defType.IsHomogeneousAggregate)
{
CorElementType elementType = (defType.ValueTypeShapeCharacteristics & ValueTypeShapeCharacteristics.AggregateMask) switch
{
ValueTypeShapeCharacteristics.Float32Aggregate => CorElementType.ELEMENT_TYPE_R4,
ValueTypeShapeCharacteristics.Float64Aggregate => CorElementType.ELEMENT_TYPE_R8,
ValueTypeShapeCharacteristics.Vector64Aggregate => CorElementType.ELEMENT_TYPE_R8,
// See MethodTable::GetHFAType
ValueTypeShapeCharacteristics.Vector128Aggregate => CorElementType.ELEMENT_TYPE_VALUETYPE,
_ => CorElementType.Invalid
};
dataBuilder.EmitUInt((uint)elementType);
}
if (alignment != pointerSize)
{
dataBuilder.EmitUInt((uint)alignment);
}
if (defType.ContainsGCPointers)
{
// Encode the GC pointer map
GCPointerMap gcMap = GCPointerMap.FromInstanceLayout(defType);
byte[] encodedGCRefMap = new byte[(size / pointerSize + 7) / 8];
int bitIndex = 0;
foreach (bool bit in gcMap)
{
if (bit)
{
encodedGCRefMap[bitIndex / 8] |= (byte)(1 << (bitIndex & 7));
}
++bitIndex;
}
dataBuilder.EmitBytes(encodedGCRefMap);
}
}
private static void EncodeTypeLayout(ObjectDataSignatureBuilder dataBuilder, TypeDesc type)
{
Debug.Assert(type.IsValueType);
MetadataType defType = (MetadataType)type;
int pointerSize = type.Context.Target.PointerSize;
int size = defType.InstanceFieldSize.AsInt;
int alignment = GetClassAlignmentRequirement(defType);
ReadyToRunTypeLayoutFlags flags = ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_Alignment | ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_GCLayout;
if (alignment == pointerSize)
{
flags |= ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_Alignment_Native;
}
if (!defType.ContainsGCPointers)
{
flags |= ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_GCLayout_Empty;
}
if (defType.IsHfa)
{
flags |= ReadyToRunTypeLayoutFlags.READYTORUN_LAYOUT_HFA;
}
dataBuilder.EmitUInt((uint)flags);
dataBuilder.EmitUInt((uint)size);
if (defType.IsHfa)
{
switch (defType.HfaElementType.Category)
{
case TypeFlags.Single:
dataBuilder.EmitUInt((uint)CorElementType.ELEMENT_TYPE_R4);
break;
case TypeFlags.Double:
dataBuilder.EmitUInt((uint)CorElementType.ELEMENT_TYPE_R8);
break;
}
}
if (alignment != pointerSize)
{
dataBuilder.EmitUInt((uint)alignment);
}
if (defType.ContainsGCPointers)
{
// Encode the GC pointer map
GCPointerMap gcMap = GCPointerMap.FromInstanceLayout(defType);
byte[] encodedGCRefMap = new byte[(size / pointerSize + 7) / 8];
int bitIndex = 0;
foreach (bool bit in gcMap)
{
if (bit)
{
encodedGCRefMap[bitIndex / 8] |= (byte)(1 << (bitIndex & 7));
}
++bitIndex;
}
dataBuilder.EmitBytes(encodedGCRefMap);
}
}
