protected override void UpdateLayout(DwarfLayoutContext layoutContext)
{
ulong sizeOf = 0;
// unit_length
sizeOf += DwarfHelper.SizeOfUnitLength(Is64BitEncoding);
// version
sizeOf += 2;
// debug_info_offset
sizeOf += DwarfHelper.SizeOfUInt(Is64BitEncoding);
// Address size
sizeOf += 1;
// segment selector size
sizeOf += 1;
var align = (ulong)SegmentSelectorSize + (ulong)AddressSize * 2;
// SPECS 7.21: The first tuple following the header in each set begins at an offset that is a multiple of the size of a single tuple
sizeOf = AlignHelper.AlignToUpper(sizeOf, align);
// SizeOf ranges + 1 (for last 0 entry)
sizeOf += ((ulong)Ranges.Count + 1UL) * align;
Size = sizeOf;
if (Unit != null)
{
DebugInfoOffset = Unit.Offset;
}
}
protected override void Write(DwarfWriter writer)
{
var startOffset = writer.Offset;
// unit_length
writer.WriteUnitLength(Size - DwarfHelper.SizeOfUnitLength(Is64BitEncoding));
// version
writer.WriteU16(Version);
// debug_info_offset
var debugInfoOffset = DebugInfoOffset;
if (writer.EnableRelocation)
{
writer.RecordRelocation(DwarfRelocationTarget.DebugInfo, writer.SizeOfUIntEncoding(), debugInfoOffset);
debugInfoOffset = 0;
}
writer.WriteUIntFromEncoding(debugInfoOffset);
// address_size
writer.AddressSize = AddressSize;
writer.WriteU8((byte)AddressSize);
writer.WriteU8((byte)SegmentSelectorSize);
var align = (ulong)SegmentSelectorSize + (ulong)AddressSize * 2;
// SPECS 7.21: The first tuple following the header in each set begins at an offset that is a multiple of the size of a single tuple
var nextOffset = AlignHelper.AlignToUpper(writer.Offset, align);
for (ulong offset = writer.Offset; offset < nextOffset; offset++)
{
writer.WriteU8(0);
}
Debug.Assert(writer.Offset == nextOffset);
foreach (var range in Ranges)
{
if (SegmentSelectorSize != 0)
{
switch (SegmentSelectorSize)
{
case DwarfAddressSize.Bit8:
writer.WriteU8((byte)range.Segment);
break;
case DwarfAddressSize.Bit16:
writer.WriteU16((ushort)range.Segment);
break;
case DwarfAddressSize.Bit32:
writer.WriteU32((uint)range.Segment);
break;
case DwarfAddressSize.Bit64:
writer.WriteU64((ulong)range.Segment);
break;
}
}
writer.WriteAddress(DwarfRelocationTarget.Code, range.Address);
writer.WriteUInt(range.Length);
}
if (SegmentSelectorSize != 0)
{
switch (SegmentSelectorSize)
{
case DwarfAddressSize.Bit8:
writer.WriteU8(0);
break;
case DwarfAddressSize.Bit16:
writer.WriteU16(0);
break;
case DwarfAddressSize.Bit32:
writer.WriteU32(0);
break;
case DwarfAddressSize.Bit64:
writer.WriteU64(0);
break;
}
}
switch (AddressSize)
{
case DwarfAddressSize.Bit8:
writer.WriteU16(0);
break;
case DwarfAddressSize.Bit16:
writer.WriteU32(0);
break;
case DwarfAddressSize.Bit32:
writer.WriteU64(0);
break;
case DwarfAddressSize.Bit64:
writer.WriteU64(0);
writer.WriteU64(0);
break;
}
Debug.Assert(writer.Offset - startOffset == Size);
}