[asterisk-bugs] [Zaptel 0011283]: [patch] Blackfin optimizations in arith.h

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=11283 
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Reported By:                otterson
Assigned To:                
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Project:                    Zaptel
Issue ID:                   11283
Category:                   General
Reproducibility:            always
Severity:                   tweak
Priority:                   normal
Status:                     new
Zaptel Version:              SVN 
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!): 3239 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             11-18-2007 10:39 CST
Last Modified:              11-19-2007 07:13 CST
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Summary:                    [patch] Blackfin optimizations in arith.h
Description: 
This is an optimization tweak for zaptel's arith.h.  The purpose of the
tweak is to improve the performance of zaptel conference mixer on the
Blackfin/uclinux platform.  This tweak should have no effect on any other
platforms.

The tweak replaces the ACSS and SCSS saturating add and subtract code with
a blackfin GCC builtin function that uses the Blackfin's internal
saturating add and subtract instructions.  This eliminates one or two
conditional branches for every sample added to the mix.
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---------------------------------------------------------------------- 
 otterson - 11-19-07 07:13  
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BFIN is a gcc architecture macro defined by the GCC compiler.  You can find
the source if you look in the Blackfin uClinux
toolchain/gcc-4.1/gcc/config/bfin/bfin.h

If you are using gcc with bfin-uclinux outputs you will have the BFIN
macro defined by the compiler.

Jeff 

Issue History 
Date Modified   Username       Field                    Change               
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11-19-07 07:13  otterson       Note Added: 0073913                          
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