OpenMathLib / OpenMathLib/OpenBLAS
AMD Zen 5 architecture is misidentified
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- Dominant language
- C
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Description
The attached reproducer crashes on AMD Zen 5, but succeeds when run with OPENBLAS_CORETYPE=HASWELL or OPENBLAS_CORETYPE=SKYLAKEX. It also fails with OPENBLAS_CORETYPE=GENERIC which doesn't make sense to me.
The offending instruction is: movaps %xmm0,0x0(%r13)
openblas-0.3.34
clang version 21.1.8
OS: FreeBSD 15.1
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First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the attached reproducer.c and run it on AMD Zen 5 using OpenBLAS 0.3.34, comparing the HASWELL, SKYLAKEX, and GENERIC OPENBLAS_CORETYPE settings. Trace the failing movaps instruction and the architecture identification path; done means Zen 5 is identified correctly and the reproducer no longer crashes under the default and GENERIC settings.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- c
- Domain
- performance
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Active
- Clarity
- Mostly clear
- Newbie friendliness
- 48/100