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Question about AMD vs INTEL CPU using IFC

Brian_A_
Novice
‎07-26-2011 08:40 AM
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If we compile a program that generates mathematical results on an INTEL CPU and a end user runs it on a AMD CPU, could they get different results? Is the floating point calculations different?
We have a end user who is getting different results than us. THey are using RedHat Linux Enterprise 6.1 on a AMD Opteron CPU. We have tried openSuse, RedHat Linux Enterprise 6, and Windows 7 on a INTEL CPU, and all three get the same resluts but different than the end user.
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TimP
Honored Contributor III
‎07-26-2011 08:47 AM
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The imf-arch-consistency=true option, first implemented in ifort 12.0.4, is intended to produce more accurate results uniformly across various CPU models. It reduces performance of svml (vectorized math library).
-prec-div -prec-sqrt also avoid generation of code which gives slightly different results on AMD.
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