Avoid FCA loads and extractvalue when copying fat pointers #29963
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
Since fat pointers do not qualify as structural types, they got copied using load_ty and store_ty, which means that we load an FCA and use extractvalue to get the components of the fat pointer. This breaks certain optimizations in LLVM. Found via apasel422/ref_count#13
|
r? @brson (rust_highfive has picked a reviewer for you, use r? to override) |
|
@bors r+ |
|
📌 Commit 6741f33 has been approved by |
bors
added a commit
that referenced
this pull request
Nov 21, 2015
Since fat pointers do not qualify as structural types, they got copied using load_ty and store_ty, which means that we load an FCA and use extractvalue to get the components of the fat pointer. This breaks certain optimizations in LLVM. Found via apasel422/ref_count#13
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Outdated suggestions cannot be applied.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.
Since fat pointers do not qualify as structural types, they got copied
using load_ty and store_ty, which means that we load an FCA and use
extractvalue to get the components of the fat pointer. This breaks
certain optimizations in LLVM.
Found via apasel422/ref_count#13