[compiler-rt][AArch64][Android] Use getauxval on Android. #102979
Merged
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
__getauxval is a libgcc function that doesn't exist on Android.
|
Calling getauxval on Android is fine since: The original motivation is broken as compiler-rt does call getauxval a lot from other places as of today. |
compnerd
reviewed
Aug 13, 2024
| static _Bool has_sme(void) { | ||
| return __getauxval(AT_HWCAP2) & HWCAP2_SME; | ||
| } | ||
| static _Bool has_sme(void) { return GETAUXVAL(AT_HWCAP2) & HWCAP2_SME; } |
There was a problem hiding this comment.
I think that I would rather that we inline the use of __getauxval. getauxval is a GNU "standard" interface, but was introduced in glibc only in 2.16. I don't know if anyone is targeting an older glibc, but we can do something like:
Suggested change
| static _Bool has_sme(void) { return GETAUXVAL(AT_HWCAP2) & HWCAP2_SME; } | |
| static _Bool has_sme(void) { | |
| #if defined(__GLIBC__) && !__GLIBC_PREREQ(2,16) | |
| unsigned long int auxval = __getauxval(AT_HWCAP2); | |
| #else | |
| unsigned long int auxval = getauxval(AT_HWCAP2); | |
| #endif | |
| return auxval & HWCAP2_SME; | |
| } |
There was a problem hiding this comment.
AArch64 support for getauxval just added in 2.17.
Compiler-rt uses getauxval with glibc in multiple places(SLE_Atomic, FMV, Sanitizers), so I don't see the point why use __getauxval only here.
I don't think we need to worry about such a platform that has SME while doesn't have getauxval
There was a problem hiding this comment.
It avoids the macros and allows us to have a single platform agnostic implementation. Over time, we would drop the use of the underscore variant of the function.
sdesmalen-arm
approved these changes
Aug 29, 2024
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/66/builds/3256 Here is the relevant piece of the build log for the reference |
lemenkov
pushed a commit
to lemenkov/libyuv
that referenced
this pull request
Oct 15, 2024
This reverts commit 51e2e12. Reason for revert: The llvm bug fix llvm/llvm-project#102979 has been rolled into Chrome in https://chromium-review.googlesource.com/5921462. Original change's description: > Do not enable libyuv_use_sme for is_android > > Revert the changes to libyuv.gni in commit dfa279f. > > The linker error "undefined symbol: __getauxval" referenced by > sme-abi-init.c:26 on Android, previously reported in > https://libyuv.g-issues.chromium.org/issues/359006069#comment2, has not > been fixed yet. See > https://chromium-review.googlesource.com/c/chromium/src/+/5918245?tab=checks. > > Change-Id: I94bd243e2863b9c316909f63f757fd95ec55dc18 > Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/5917455 > Reviewed-by: Frank Barchard <[email protected]> Bug: 359006069 Change-Id: Ic801c1bcb65894fdfe718ba6454669c8623a2e15 Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/5935026 Reviewed-by: Frank Barchard <[email protected]> Bot-Commit: Rubber Stamper <[email protected]> Reviewed-by: George Steed <[email protected]>
1 task
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.
__getauxval is a libgcc function that doesn't exist on Android.