Support stepping through Darwin "branch islands" (#139301) #10750
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
When an intra-module jump doesn't fit in the immediate branch slot, the Darwin linker inserts "branch island" symbols, and emits code to jump from branch island to branch island till it makes it to the actual function. The previous submissions failed because in that environment the linker was putting the `foo.island` symbol at the same address as the `padding` symbol we we emitting to make our faked-up large binary. This submission jams a byte after the padding symbol so that the other symbols can't overlap it. (cherry picked from commit 952b680)
|
@swift-ci test |
adrian-prantl
approved these changes
May 27, 2025
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Outdated suggestions cannot be applied.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.
When an intra-module jump doesn't fit in the immediate branch slot, the Darwin linker inserts "branch island" symbols, and emits code to jump from branch island to branch island till it makes it to the actual function.
The previous submissions failed because in that environment the linker was putting the
foo.islandsymbol at the same address as thepaddingsymbol we we emitting to make our faked-up large binary. This submission jams a byte after the padding symbol so that the other symbols can't overlap it.(cherry picked from commit 952b680)