Hi Andrea, on 2020/9/4 下午8:11, Andrea Corallo wrote: > Hi all, > > just a small patch removing a piece of unreachable code in > 'vect_estimate_min_profitable_iters' given the condition > (LOOP_VINFO_USING_PARTIAL_VECTORS_P (loop_vinfo)) is always true as > checked just above. >
FWIW, I had the same confusion when I saw the code at the first time, the comments at outer if "??? The "if" arm ..." and the commit messages seem to give some hints. IIUC, the code in this outer "if" was implemented to handle all cases but that time was stage 4, so it's conservative to be guarded as fully-predicated only to avoid the potential risks. I was imagining that it would finally end up by removing this outer if condition guard and the outer else. But not sure why it didn't change in the following stage1. Maybe Richard S. (the author) will have some comments. BR, Kewen
