PTX Compression Method

Following this old thread regarding how PTX is compressed inside a fatbinary:

https://devtalk.nvidia.com/default/topic/951929/how-to-retrieve-ptx-code-from-the-binary-file-without-using-cuobjdump-

Which is the compression method employed by the NVCC toolchain?

This method seems to be employed starting from CUDA 5. Back to CUDA 3/4 the PTX was saved in plaintext.

Same question asked differently?
https://devtalk.nvidia.com/default/topic/1042212/cuda-programming-and-performance/demistifying-cuda-fat-binaries/

Actually I’m the same author of the question you mentioned, but the question was a bit different: it was related to the fatbinary organization.

Now the point is how PTX code is compressed.