Switch `DGMulti` to `Matrix{<:SVector}` solution storage

[jlchan]

Also bumps StartUpDG.jl compat to 1.0.

[github-actions[bot]]

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[codecov[bot]]

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[jlchan]

I am running into issues due to Polyester.@batch turning arrays into StrideArraysCore.PtrArrays". For a Navier-Stokes solve, this dispatches to Octavian.matmul! via https://github.com/JuliaSIMD/StrideArrays.jl/blob/d31fb6cf28b0374162202da8c81694f2b704e0f3/src/blas.jl#L6.

For now, I'll just focus on the single-threaded case, but dealing with multi-threading will require figuring out if Polyester and StrideArrays will continue after stopping support of LoopVec.jl and Octavian.jl in Julia v1.11 (cc @chriselrod)

[chriselrod]

For a Navier-Stokes solve, this dispatches to Octavian.matmul! via https://github.com/JuliaSIMD/StrideArrays.jl/blob/d31fb6cf28b0374162202da8c81694f2b704e0f3/src/blas.jl#L6.

Feel free to PR it to drop Octavian as a dependency.

For now, I'll just focus on the single-threaded case, but dealing with multi-threading will require figuring out if Polyester and StrideArrays will continue after stopping support of LoopVec.jl and Octavian.jl in Julia v1.11

Regardless of the official status, you don't have to rush to make changes. There are no test failures on 1.11.

[jlchan]

For a Navier-Stokes solve, this dispatches to Octavian.matmul! via https://github.com/JuliaSIMD/StrideArrays.jl/blob/d31fb6cf28b0374162202da8c81694f2b704e0f3/src/blas.jl#L6.

Feel free to PR it to drop Octavian as a dependency.

For now, I'll just focus on the single-threaded case, but dealing with multi-threading will require figuring out if Polyester and StrideArrays will continue after stopping support of LoopVec.jl and Octavian.jl in Julia v1.11

Regardless of the official status, you don't have to rush to make changes. There are no test failures on 1.11.

Thanks - I removed the LinearAlgebra.mul! overloads in https://github.com/jlchan/StrideArrays.jl/blob/d31fb6cf28b0374162202da8c81694f2b704e0f3/src/blas.jl#L2-L36. It runs, but the solution gets NaNs. When I switch @batch to Threads.@threads, I get an error that seems related to @turbo:

ERROR: TaskFailedException

    nested task error: UndefRefError: access to undefined reference

so I think I'm going to have to dig a little deeper beyond removing Octavian dependencies to figure out what's going wrong...