Thankfully, the P-cores are nowhere near as bad as the Pentium 4 was. The Pentium 4 had such a skewed architecture that it was annoyingly frustrating to optimize for. Not only was the branch misprediction penalty long, but all common methods of doing branchless logic like conditional moves were also slow. It also had a slow shifter such that small left shifts were actually faster as sequences of adds, which I hadn't needed to do since the 68000 and 8086. And an annoying L1 cache that had 64K aliasing penalties (guess which popular OS allocates all virtual memory, particularly thread stacks, at 64K alignment.....)

The P-cores have their warts, but are still much more well-rounded than the P4 was.