🍒 [WebAssembly] Define local sp if llvm.stacksave is used
#7563
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
|
@swift-ci Please test |
kateinoigakukun
force-pushed
the
yt/wasm-stacksave-dom
branch
from
f5e7561 to
6c4bb7a
Compare
|
@swift-ci Please test |
kateinoigakukun
changed the title
llvm.stacksave is usedllvm.stacksave is used
MaxDesiatov
approved these changes
Oct 3, 2023
|
Should this target a different branch though? stable/20221013 is quite old, I'm not sure if it corresponds to the current Swift branch |
Usually `llvm.stacksave/stackrestore` are used together with `alloca` but they can appear without it (e.g. `alloca` can be optimized away). WebAssembly's function local physical user sp register, which is referenced by `llvm.stacksave` is created while frame lowering and replaced with virtual register. However the sp register was not created when `llvm.stacksave` is used without `alloca`, and it led MIR verification failure about use-before-def of sp virtual register. Resolves llvm#62235
kateinoigakukun
changed the base branch from
stable/20221013
to
stable/20230725
kateinoigakukun
force-pushed
the
yt/wasm-stacksave-dom
branch
from
6c4bb7a to
44efb09
Compare
|
@swift-ci Please test |
MaxDesiatov
approved these changes
Oct 4, 2023
|
@swift-ci Please test |
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Outdated suggestions cannot be applied.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.
Cherry-pick: da0ca5d
Resolves: rdar://116374985
Usually
llvm.stacksave/stackrestoreare used together withallocabut they can appear without it (e.g.allocacan be optimized away). WebAssembly's function local physical user sp register, which is referenced byllvm.stacksaveis created while frame lowering and replaced with virtual register. However the sp register was not created whenllvm.stacksaveis used withoutalloca, and it led MIR verification failure about use-before-def of sp virtual register.