Custom Ops: Unit Tests

[matthewdouglas]

Provide unit testing coverage for all new custom ops.

• Tests must support CUDA and, where applicable, CPU devices

• Must be device-agnostic, i.e. can add support for additional devices for new backends.

• Tests must pass the torch.library.opcheck tests.

• Tests must use all combinations of supported data types and options for each op.

• Operator tests should compare CPU outputs with accelerator outputs with low tolerance for divergence

• Int8 blockwise quant/dequant

• LLM.int8 quant/dequant

• LLM.int8 matmul

• 4bit blockwise quant/dequant

• 4bit matmul