https://community.intel.com/t5/Software-Archive/IA64-Branch-Mispredict-Predicate-bit-Vs-Mispredict/m-p/948481#M18939 Predication is used to make a branch conditional. Maybe you mean the branch hints, which can be used to initialize branch prediction to "taken" or "not taken." The first time the predication doesn't match the hint, for example on loop exit, there would always be a mis-predict. Later on, if the predication matches a pattern stored in branch history, it may be possible to "predict," if the pattern continues.<BR />Normally, the hint is set by the compiler, by rules such as backward jump taken, forward conditional jump not taken, and, we hope, loop exit not taken. If the compiler is instructed to use a profiling history, it would set the hints accordingly. Wed, 01 Feb 2006 03:58:24 GMT TimP 2006-02-01T03:58:24Z https://community.intel.com/t5/Software-Archive/IA64-Branch-Mispredict-Predicate-bit-Vs-Mispredict/m-p/948480#M18938 <DIV>With Itanium I understand there is a predicate bit that can avoid branch mispredict events in some cases. Yet in other cases,branch mispredicts still occur in IA64. </DIV> <DIV></DIV> <DIV>My questions is what is the factor in Itanium architecture which determines a branch mispredict vs. a predicated branch?</DIV> <DIV></DIV> <DIV>Thanks in advance</DIV> <DIV>Mark</DIV> Wed, 01 Feb 2006 03:14:47 GMT https://community.intel.com/t5/Software-Archive/IA64-Branch-Mispredict-Predicate-bit-Vs-Mispredict/m-p/948480#M18938 mark-whitener 2006-02-01T03:14:47Z https://community.intel.com/t5/Software-Archive/IA64-Branch-Mispredict-Predicate-bit-Vs-Mispredict/m-p/948481#M18939 Predication is used to make a branch conditional. Maybe you mean the branch hints, which can be used to initialize branch prediction to "taken" or "not taken." The first time the predication doesn't match the hint, for example on loop exit, there would always be a mis-predict. Later on, if the predication matches a pattern stored in branch history, it may be possible to "predict," if the pattern continues.<BR />Normally, the hint is set by the compiler, by rules such as backward jump taken, forward conditional jump not taken, and, we hope, loop exit not taken. If the compiler is instructed to use a profiling history, it would set the hints accordingly. Wed, 01 Feb 2006 03:58:24 GMT https://community.intel.com/t5/Software-Archive/IA64-Branch-Mispredict-Predicate-bit-Vs-Mispredict/m-p/948481#M18939 TimP 2006-02-01T03:58:24Z