Request: ARM SME support (for Apple M4)..

[oscarbg]

No need for unofficial Apple AMX intruction set on M4..
2tflops possible..

[martin-frbg]

PRs welcome... do you have the hardware to test ?

[oscarbg]

Not yet.. waiting for a mac mini m4..

[brada4]

I think this can be closed, zero chance to run your cpuid on ipad, and normal computers release year later.
AMX is NOT ISA , it is a co-processor with prefixed instructions emitted from main cpu. Like FPU on 80386 or crypto accelerators nowadays. There is no public documentation outsude accelerate cblas using it.

[martin-frbg]

try reading that again, it's about SME...

[brada4]

SME

Which is rumoured on some sites to be present....

[Mousius]

You can develop and test using the Fixed Virtual Platform (FVP):
apache/tvm#16755
apache/tvm#16749

[brada4]

Gcc11+ can compile it, the question is whether itvis supported on particular cpu.

[martin-frbg]

some implementation hints there: https://scalable.uni-jena.de/opt/sme/index.html

[oscarbg]

Hi,
any news?
have a Mac Mini m4 to test..

[martin-frbg]

Bought an M4 mini myself recently but have not gotten around to doing much with it yet.

[martin-frbg]

#5084 added SME for the "small matrix" SGEMM pathway but needs some small tweaks to connect the M4 cpu target to it

#5011 has a more general SME GEMM kernel but needs fixes for proper SYMM/TRMM support before it can be merged

[ITCJ]

#5084 added SME for the "small matrix" SGEMM pathway but needs some small tweaks to connect the M4 cpu target to it

#5011 has a more general SME GEMM kernel but needs fixes for proper SYMM/TRMM support before it can be merged

Based on a SC24 workshop Hello SME, llvm/llvm-project#114987 and llvm/llvm-project#95478 . Apple M4 does not support SVE outside of streaming.
However, concurrent [WIP] #5011 is on top of KERNEL.ARMV8SVE. Result in illegal instruction. Any good ideas to solve that? Is create a new KERNEL.M4SME2 based on KERNEL.ARMV8 a good idea?

[ITCJ]

Further more, I have made some test on differences between SME1 and SME2 recently. It's quiet different to achieve best performance.
I don‘t known if ACLE could fully utilize these resources.

[martin-frbg]

Yes, M4 only does streaming SVE so you'd need at least some setup code to enter streaming mode and perhaps save some dual-use registers beforehand, or even work in a totally different set of registers than what the existing SVE code uses.

Both #5011 and #5084 introduced an ARMV9SME target for differentiation, it would also be possible to select kernel implementations (either at the KERNEL file level or within individual implementations) based on HAVE_SME or a similiar define. As #5011 is a WIP only concerned with GEMM and related functions, it does not work outside its narrow scope.

The way forward - at least short-term - should be to split out M4 from the general "VORTEX" target into its own designation and enable the SME-based "small gemm" pathway for it. I hope to complete this very soon.

[violet73]

Hi, I would like to ask why I encountered the following error on M4pro:

Is it possible that my compiler does not recognize streaming flags?

Compilation:
clang -g -O0 -march=armv9.2-a+sme+sme2 ./test_sme_acle.cc -o ./test_sme_acle

Clang version:
Homebrew clang version 20.1.2
Target: arm64-apple-darwin24.3.0
Thread model: posix
InstalledDir: /opt/homebrew/Cellar/llvm/20.1.2/bin