MMIX instruction set specifies the branch prediction explicitly.
If you also have a "branch always" and "branch never" and the compiler can generate a code to modify that instruction during the initialization of the program, then for some programs where some of the branches are known during initialization, it might modify the code when it is initialized before it is executed.
If you also have a "branch always" and "branch never" and the compiler can generate a code to modify that instruction during the initialization of the program, then for some programs where some of the branches are known during initialization, it might modify the code when it is initialized before it is executed.