hwtest: Instead of replacer, run a binary archive?

[geohot]

The wrap/replacer.dylib API is unstable. Any reason you can't load a custom shader from a BinaryArchive and run it? Do you need something lower level for the hardware tests?

[dougallj]

Yeah, that's a good idea – I just wasn't aware of MTLBinaryArchive at the time. I haven't tried overwriting code in binary archives, but assuming that works it should be a much more stable strategy.