Hi Prathamesh, I've tried out the latest version and it works really well. It built and ran SPEC2017 without any issues or regressions (I didn't do a detailed comparison which would mean multiple runs, however a single run showed performance is pretty much the same on INT and 0.1% faster on FP).
Codesize reduces in almost all cases (only xalancbmk increases by 600 bytes), sometimes by a huge amount. For example in gcc_r around 20% of all AND immediate instructions are removed, clear proof it removes many redundant zero/sign extensions. So consider this a big +1 from me! GCC is behind other compilers with respect to this kind of optimization and it looks like this phase does a major catchup. Like I mentioned, it doesn't have to be 100% perfect, once it has been committed, we can fine tune it and add more optimizations. Wilco