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Talk:Predication (computer architecture)

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This is an old revision of this page, as edited by Mjr1007 (talk | contribs) at 18:16, 29 July 2008 (Additional advantage: new section). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

There is a problem with the first sentence,

"Because computer programs respond to a user, there is no way around the fact that portions of a program need to be executed conditionally."

A program which computes a formula from user input may not need to branch, and conversely a program with complex logic which receives no direct inputs from a user (paging in the OS) may need to branch.

It is unclear exactly how to introduce this topic. Mjr1007 (talk) 17:24, 29 July 2008 (UTC)[reply]

Additional advantage

According to the Intel® Itanium® Architecture Software Developer’s Manual Volume 1: Application Architecture

http://download.intel.com/design/Itanium/manuals/24531705.pdf

In section 4.2.4.1

This code takes 18 cycles to complete if p2 is true and five cycles if p2 is false. When analyzing such cases, consider execution weights, branch misprediction probabilities, and prediction costs along each path.

The execution times decreases if the predicate is false.

Mjr1007 (talk) 18:16, 29 July 2008 (UTC)[reply]