I used intel parallel studio 2011, Visual Studio 2008, Window 7- 64bit
I load "ipps-7.0.dll" and "ippm-7.0.dll" in folder "C:\Program Files (x86)\Intel\Parallel Studio 2011\Composer\redist\intel64\ipp\"
then "flush to zero" is enabled.
how many dll of IPP enable "flush to zero" mode when it is loaded?
Code C# used to load:
LoadLibrary(@"C:\Program Files (x86)\Intel\Parallel Studio 2011\Composer\redist\intel64\ipp\ipps-7.0.dll");
Can you check this article for detail discussion:
FTZ mode is set by Intel compiler in the init(section) that is called before dllmain() - it's default compiler behavior if "-fp:precise" switch is not used. (IPP is built with Intel compiler.). All IPP DLL will set this.
In your case you can set this bit to the state you need at the very beginning of your application with call to
IPPAPI( IppStatus, ippSetFlushToZero, ( int value, unsigned int* pUMask ))
or use static IPP libraries that will not set the FlushToZero flag.