[jeffbee]

FYI. https://quick-bench.com/q/sK9t9GoFDRkx9XxloUUbB8Q3ht4'

Using this microbenchmark on an Intel Sapphire Rapids CPU, compiled with march=k8 to get the older form, takes ~980ns, while compiling with march=native gives ~570ns. It's not at all clear that the imperfection the article describes is really relevant in context, because the compiler transforms this function into something quite different.

[fooker]

With random test cases, branch prediction can't help.