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While Loop Optimization

I have a while loop that tests the value of (A*B > SomeNumber). This while loop is repeated at the very least several million times so code efficency is very importatant. A and B do not change while the loop is running. My question is would it be more efficent to first get the product of A and B and then test that variable against SomeNumber, or does it not matter?

Any other tips for optimization would be helpful too, thanks in advance.

[457 byte] By [NeederOfVBHelp] at [2007-12-25]
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# 1
This is a general advice reply...look into NGen tool for performance upgrades at the assembly / application level. Read up on it in an MSDN article NGen Revs Up Your Performance with Powerful New Features.
OmegaMan at 2007-9-3 > top of Msdn Tech,Visual C#,Visual C# Language...
# 2
I appreciate your help, although I don't think using NGen will help my program.
NeederOfVBHelp at 2007-9-3 > top of Msdn Tech,Visual C#,Visual C# Language...
# 3
As to your original question, if A&B don't change it might be best to extract them outside the loop. Optimizers have to guage if those variables are going to change when it decides to optimize...its rules may say no for your situation.. Any help you can give to the underlying framework is best...

One other thing you may want to look into is Performance Best Practices at a Glance.

OmegaMan at 2007-9-3 > top of Msdn Tech,Visual C#,Visual C# Language...
# 4
This is a common optimization target named "Loop Invariant Hoisting Optimization". I know the C++ backend optimizer was good at doing this; not sure about the .NET code generators (the MSIL emitter and the JIT compiler). Of course, it is easy to just try it...
nobugz at 2007-9-3 > top of Msdn Tech,Visual C#,Visual C# Language...
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