> Historically there was a notion of "clean room" reimplementation
These projects start off with the original assembly code and use it actively throughout all stages. This is about as far away from clean room as you get.
These projects do not start with assembly. They start with machine code interleaved with data. Even getting to assembly through a disassembled requires some input and understanding. Usually these are raw binaries with no (or limited) metadata.
When run through a disassembler, in most cases, it’s probably the first time anyone has ever looked at the assembly (assuming PlayStation or newer). There are no comments or labels or symbols. Not what most people would consider “the original assembly”.
These projects do not start with assembly. They start with machine code interleaved with data. Even getting to assembly through a disassembled requires some input and understanding. Usually these are raw binaries with no (or limited) metadata.
When run through a disassembler, in most cases, it’s probably the first time anyone has ever looked at the assembly (assuming PlayStation or newer). There are no comments or labels or symbols. Not what most people would consider “the original assembly”.