Collection expressions: empty Span optimization #70260
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
dotnet-issue-labeler
bot
added
Area-Compilers
untriaged
cston
approved these changes
Oct 5, 2023
|
Love it |
jcouv
reviewed
Oct 5, 2023
| IL_0005: newobj "System.ReadOnlySpan<T>..ctor(T[])" | ||
| IL_000a: call "MyCollection<T> MyCollectionBuilder.Create<T>(scoped System.ReadOnlySpan<T>)" | ||
| IL_000f: ret | ||
| .locals init (System.ReadOnlySpan<T> V_0) |
There was a problem hiding this comment.
Do we understand why the new codegen involves an additional local and IL instruction?
There was a problem hiding this comment.
initobj expects an address on the stack. In some cases a new local is introduced in order to provide that.
|
Note: we should do this for 17.8. This is a very trivial change, but important to our messaging about collections and perf. Having a core span scenario work well is high on that list. |
RikkiGibson
merged commit 8fc28af
into
dotnet:features/CollectionLiterals
25 checks passed
17 tasks
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Part of #68785