Has it been verified that they actually use these instructions in Accelerate.framework? Yes. Aside from benchmarks, you can easily verify this by profiling an

Has it been verified that they actually use these instructions in Accelerate.framework? Yes. Aside from benchmarks, you can easily verify this by profiling an application with Instruments and then inspecting the disassembly. However, it should be said that AMX does not scale linearly with the number of cores, but with the number of core clusters. So, on the M1 if you use Accelerate in two threads (rather than one), performance will barely improve, because the first thread can keep the AMX unit busy enough. However, e.g. the M1 Pro and M1 Max have two performance core clusters with AMX units in them. So matrix multiplication doubles roughly two times compared to the M1. Similarly, the M1 Ultra has fours performance core clusters, so matrix multiplication performance is roughly twice that of the M1 Pro/Max and four times that of the M1. Benchmarks: https://github.com/danieldk/gemm-benchmark#1-to-16-threads https://github.com/danieldk/gemm-benchmark#1-to-16-threads