Skip to content

Use Guid(ReadOnlySpan<Byte>) ctor #119010

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
xtqqczze wants to merge 2 commits into from
Closed

Use Guid(ReadOnlySpan<Byte>) ctor #119010

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
d704459
Fix memory storage of `Guid`
xtqqczze Aug 22, 2025
e68fa9a
address feedback
xtqqczze Aug 22, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventProvider.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -383,8 +383,8 @@ to fill the passed in ETW data descriptor.
else if (data is Guid)
{
dataDescriptor->Size = (uint)sizeof(Guid);
Guid* guidptr = (Guid*)dataBuffer;
*guidptr = (Guid)data;
void* guidptr = dataBuffer;
((Guid)data).TryWriteBytes(new Span<byte>(ref *(byte*)guidptr, sizeof(Guid)));
dataDescriptor->Ptr = (ulong)guidptr;
}
else if (data is decimal)
Expand Down
4 changes: 2 additions & 2 deletions src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1902,8 +1902,8 @@ private static unsafe void DecodeObjects(object?[] decodedObjects, Type[] parame
}
else if (dataType == typeof(Guid))
{
Debug.Assert(size == 16);
decoded = *(Guid*)dataPointer;
Debug.Assert(size == sizeof(Guid));
decoded = new Guid(new ReadOnlySpan<byte>(ref *(byte*)dataPointer, sizeof(Guid)));
}
else
{
Expand Down
9 changes: 7 additions & 2 deletions src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/BlobReader.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -311,14 +311,18 @@ public double ReadDouble()

public Guid ReadGuid()
{
const int size = 16;
byte* ptr = GetCurrentPointerAndAdvance(size);
byte* ptr = GetCurrentPointerAndAdvance(sizeof(Guid));

#if NET
Copy link
Member

@jkotas jkotas Aug 22, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I do not think that this change is worth it. It is adding ifdef, it is not reducing amount of unsafe code, and it may make the code a bit slower.

return new Guid(MemoryMarshal.CreateReadOnlySpan(ref *ptr, sizeof(Guid)));
#else
if (BitConverter.IsLittleEndian)
{
return *(Guid*)ptr;
}
else
{
Debug.Assert(sizeof(Guid) == 16);
unchecked
{
return new Guid(
Expand All @@ -328,6 +332,7 @@ public Guid ReadGuid()
ptr[8], ptr[9], ptr[10], ptr[11], ptr[12], ptr[13], ptr[14], ptr[15]);
}
}
#endif
}

/// <summary>
Expand Down
Loading