Itanium Predication / Branching

[kevinp83]

Hello everyone.

I've used both predication and branching to if..then..else and multiway branching. However, I'm sure there are drawbacks for using predication, e.g. when there are long branches, unbalanced branches etc.

How can I decide when to use branching, and when to use predication. Have there been any analytical or empirical studies about this? It would be an interesting read.


Regards,
K. Phillips

[Kalyan_M_Intel]

Hi,

The Intel Itanium Architecture Software Developer's Manual Revision 2.2(http://download.intel.com/design/Itanium/manuals/24531705.pdf) will provide the answers to your questions. Please see chapter 4 (section 4.2 "Predication") starting at page 1:163. It talks about when to use branches and when to use predication. If you have any further questions after reading this chapter, do let us know.

Regards,

Kalyan Muthukumar

[kevinp83]

Many thanks. That was helpful. Makes my if-conversion heuristics work better ..

Regards,
K.Phillips