These most recent optimizations are nowhere near 10x faster. The only one that can even come close is autovectorization and that can be done without heavy reliance on UB.
If your loop is worth autovectorizing the 2 instructions to check for pointer aliasing, and other showstoppers is not material.
If your loop is worth autovectorizing the 2 instructions to check for pointer aliasing, and other showstoppers is not material.