The Pentium 4 introduced prefix opcodes that hinted that the next branch would be likely or unlikely to be taken. These are still legal, but afaik post-NetBurst

The Pentium 4 introduced prefix opcodes that hinted that the next branch would be likely or unlikely to be taken. These are still legal, but afaik post-NetBurst CPUs ignore them, and Intel's optimization manuals have dropped mention of them.