The compiler makes the first branch prediction table. (It's actually smaller than a branch prediction table, because it only needs one exit point for each entry

The compiler makes the first branch prediction table. (It's actually smaller than a branch prediction table, because it only needs one exit point for each entry point.) The table can be updated (in memory) during execution if needed. The on-disk version can be modified for optimization purposes for later runs, but the mechanism for that would obviously be software dependent and not reside on chip.