add get_backend for StaticArrays

[vchuravy]

Fixes #620

[vchuravy]

@mattsignorelli what would you expect for SArray?

[mattsignorelli]

SArray cannot be modified/mutated in place, so this I think makes sense to throw an error

[github-actions]

Benchmark Results

	main	b068e6e...	main / b068e6e...
saxpy/default/Float32/1024	0.0465 ± 0.029 ms	0.628 ± 0.009 μs	74 ± 45
saxpy/default/Float32/1048576	0.454 ± 0.022 ms	0.209 ± 0.025 ms	2.17 ± 0.28
saxpy/default/Float32/16384	0.0593 ± 0.027 ms	3.05 ± 0.39 μs	19.4 ± 9.1
saxpy/default/Float32/2048	0.045 ± 0.026 ms	0.758 ± 0.014 μs	59.4 ± 34
saxpy/default/Float32/256	0.0497 ± 0.029 ms	0.557 ± 0.006 μs	89.2 ± 52
saxpy/default/Float32/262144	0.157 ± 0.025 ms	0.0468 ± 0.0056 ms	3.35 ± 0.66
saxpy/default/Float32/32768	0.0607 ± 0.026 ms	5.84 ± 0.75 μs	10.4 ± 4.6
saxpy/default/Float32/4096	0.0484 ± 0.023 ms	1.15 ± 0.14 μs	42.2 ± 21
saxpy/default/Float32/512	0.0588 ± 0.029 ms	0.592 ± 0.0073 μs	99.4 ± 49
saxpy/default/Float32/64	0.0434 ± 0.028 ms	0.547 ± 0.006 μs	79.3 ± 51
saxpy/default/Float32/65536	0.0747 ± 0.026 ms	12.3 ± 1.3 μs	6.1 ± 2.2
saxpy/default/Float64/1024	0.0465 ± 0.029 ms	0.752 ± 0.018 μs	61.8 ± 39
saxpy/default/Float64/1048576	0.575 ± 0.099 ms	0.549 ± 0.098 ms	1.05 ± 0.26
saxpy/default/Float64/16384	0.0691 ± 0.026 ms	5.58 ± 0.66 μs	12.4 ± 4.9
saxpy/default/Float64/2048	0.0452 ± 0.025 ms	1.17 ± 0.14 μs	38.5 ± 22
saxpy/default/Float64/256	0.0569 ± 0.029 ms	0.582 ± 0.006 μs	97.6 ± 49
saxpy/default/Float64/262144	0.168 ± 0.024 ms	0.0959 ± 0.016 ms	1.75 ± 0.39
saxpy/default/Float64/32768	0.0673 ± 0.025 ms	12.2 ± 1.3 μs	5.52 ± 2.1
saxpy/default/Float64/4096	0.0488 ± 0.024 ms	1.81 ± 0.21 μs	27 ± 13
saxpy/default/Float64/512	0.053 ± 0.029 ms	0.631 ± 0.0079 μs	84 ± 46
saxpy/default/Float64/64	0.042 ± 0.029 ms	0.562 ± 0.0057 μs	74.8 ± 51
saxpy/default/Float64/65536	0.0885 ± 0.026 ms	24.4 ± 3.5 μs	3.62 ± 1.2
saxpy/static workgroup=(1024,)/Float32/1024	0.0464 ± 0.028 ms	2.12 ± 0.029 μs	21.9 ± 13
saxpy/static workgroup=(1024,)/Float32/1048576	0.457 ± 0.023 ms	0.209 ± 0.031 ms	2.18 ± 0.35
saxpy/static workgroup=(1024,)/Float32/16384	0.0536 ± 0.025 ms	4.35 ± 0.4 μs	12.3 ± 5.9
saxpy/static workgroup=(1024,)/Float32/2048	0.0436 ± 0.026 ms	2.27 ± 0.065 μs	19.2 ± 11
saxpy/static workgroup=(1024,)/Float32/256	0.0473 ± 0.026 ms	2.59 ± 0.045 μs	18.2 ± 10
saxpy/static workgroup=(1024,)/Float32/262144	0.157 ± 0.026 ms	0.0488 ± 0.0059 ms	3.21 ± 0.65
saxpy/static workgroup=(1024,)/Float32/32768	0.0589 ± 0.025 ms	7.37 ± 0.58 μs	7.99 ± 3.5
saxpy/static workgroup=(1024,)/Float32/4096	0.0462 ± 0.024 ms	2.59 ± 0.11 μs	17.8 ± 9.3
saxpy/static workgroup=(1024,)/Float32/512	0.0582 ± 0.027 ms	2.61 ± 0.039 μs	22.3 ± 10
saxpy/static workgroup=(1024,)/Float32/64	0.0507 ± 0.026 ms	2.63 ± 5.3 μs	19.3 ± 40
saxpy/static workgroup=(1024,)/Float32/65536	0.0746 ± 0.026 ms	14.5 ± 1.6 μs	5.15 ± 1.9
saxpy/static workgroup=(1024,)/Float64/1024	0.0459 ± 0.028 ms	2.26 ± 0.076 μs	20.3 ± 13
saxpy/static workgroup=(1024,)/Float64/1048576	0.518 ± 0.063 ms	0.527 ± 0.07 ms	0.984 ± 0.18
saxpy/static workgroup=(1024,)/Float64/16384	0.0621 ± 0.026 ms	7.33 ± 0.68 μs	8.47 ± 3.6
saxpy/static workgroup=(1024,)/Float64/2048	0.0436 ± 0.026 ms	2.57 ± 0.12 μs	16.9 ± 10
saxpy/static workgroup=(1024,)/Float64/256	0.0529 ± 0.026 ms	2.61 ± 0.057 μs	20.3 ± 10
saxpy/static workgroup=(1024,)/Float64/262144	0.164 ± 0.027 ms	0.101 ± 0.016 ms	1.63 ± 0.37
saxpy/static workgroup=(1024,)/Float64/32768	0.0653 ± 0.026 ms	15 ± 1.8 μs	4.35 ± 1.8
saxpy/static workgroup=(1024,)/Float64/4096	0.0467 ± 0.024 ms	3.17 ± 0.22 μs	14.7 ± 7.7
saxpy/static workgroup=(1024,)/Float64/512	0.0519 ± 0.028 ms	2.62 ± 0.064 μs	19.8 ± 11
saxpy/static workgroup=(1024,)/Float64/64	0.0505 ± 0.027 ms	2.57 ± 0.061 μs	19.6 ± 10
saxpy/static workgroup=(1024,)/Float64/65536	0.0842 ± 0.027 ms	27 ± 3.1 μs	3.12 ± 1.1
time_to_load	1.35 ± 0.022 s	0.316 ± 0.0016 s	4.27 ± 0.074

Benchmark Plots

A plot of the benchmark results have been uploaded as an artifact to the workflow run for this PR.
Go to "Actions"->"Benchmark a pull request"->[the most recent run]->"Artifacts" (at the bottom).