CUDA Texture Sampler

[jlaxson]

This is the next step on my texture sampler journey. I have some architecture questions, as not much feels very clear to me.

Unlike OpenCL which has a separate device interface for textures, right now I'm passing a bit of information to halide_cuda_run so it can wrap existing buffers in the texture descriptor. Tradeoff for this is only 1D and 2D samplers can be used, 3D requires allocating a cuArray.

Any thoughts, feedback welcome, I have a few extra questions inline as well.

[jlaxson]

@zvookin @abadams @steven-johnson @dsharletg

[jlaxson]

Also somewhere in codegen there should be a check that you have compute 3.0 if generating a GPUTexture buffer, but not sure where that should go

[jlaxson]

Rather unbelievably this works now. LLVM master has way way better error messages than 11 or whatever I was using before. Ready for review, beat me up.

[steven-johnson]

Opened https://github.com/halide/Halide/pull/5431 for testing

[steven-johnson]

Various test failures in the clone build, possibly related

[steven-johnson]

see https://buildbot.halide-lang.org/master/#/builders/74/builds/2

[steven-johnson]

1-month check-in. (No rush on our side of course, just want to see if this is on the backburner for a while.)

[steven-johnson]

I assume this PR is on the backburner. Please ping when the test failures get addressed.

[jlaxson]

Thanks @steven-johnson will do, hope to have some more side time come the holiday weeks.

[steven-johnson]

Post-holiday check-in: where does this PR stand?

[steven-johnson]

Is this PR still active? Should it be closed?