[Strings] string.eq #4781
Merged
[Strings] string.eq #4781
Conversation
This file contains hidden or 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
tlively
approved these changes
Jul 8, 2022
src/ir/cost.h
Outdated
| @@ -684,6 +684,10 @@ struct CostAnalyzer : public OverriddenVisitor<CostAnalyzer, CostType> { | |||
| CostType visitStringConcat(StringConcat* curr) { | |||
| return 10 + visit(curr->left) + visit(curr->right); | |||
| } | |||
| CostType visitStringEq(StringEq* curr) { | |||
| // This assumes strings are interned in the engine. | |||
There was a problem hiding this comment.
I would be surprised if all strings were interned! This seems like it should be modeled as being very expensive since it's cost is unbounded.
There was a problem hiding this comment.
I think the VM will intern them if they are used enough, at least in some cases, but I don't really know. JS string implementations are quite flexible. I guess we shouldn't strongly assume anything here, but like with concat, I don't think this can be a problem in general - there is no equivalent code that would be compared to this.
There was a problem hiding this comment.
I adjusted it to 3 (in between 1 and 6 for interned and not), and added a comment.
Co-authored-by: Thomas Lively <[email protected]>
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Outdated suggestions cannot be applied.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.
I considered maybe making this a shared class with
RefEq. They are quite similar. But the internal opcode would need to be something like "compare references" versus "compare data", which seems slightly awkward. Overall the amount of boilerplate per new class is fairly small now, so I lean towards that.