I do not know the purpose of this issue. The new code does not look cleaner to me, but maybe it is only for me.

But performance regressions should be fixed. We cannot rely on compiler-specific global optimization, which is hard to test and does not work for dynamic linkage (third-party extensions and applications with built-in Python). Even "inline" is just a hint to the compiler and does not guarantee inlining the code.

Raymond's suggestions look reasonable to me.