Cycles supports a feature known as "Adaptive Compile" which will
compile the GPU kernel at runtime with only the features neccesary
for the current scene.
This is primarily used for debugging purposes and is not advised for
general use, because it's not well tested/maintained and leads to
frequent kernel recompilation which can take a long time and interupt
your workflow.
This commits exposes the option to turn this feature on
for the HIP and Metal backends in the Cycles debug UI panel.
Pull Request: https://projects.blender.org/blender/blender/pulls/132459