As noted previously there are some cases where the performance of unmanaged code can beat that of the managed JIT. In the previous case it was the matrix multiplication function. We do have some other possible performance benefits we can give to our .NET code, specifically, we can NGEN it. NGEN is an interesting utility, it can perform heavy optimizations that would not be possible in the standard runtime JIT (as we shall see). The question before us is: Will it give us enough of a boost to be able to surpass the performance of our unmanaged matrix multiplication?

An Analysis of Existing Code

We haven't looked at the current code that was produced for our previous tests yet, so I feel that it is time we gave it a look and see what we have. To keep this shorter we'll only look at the inner product function. The code produced for the matrix multiplication suffers from the same problems and benefits from the same extensions. For the purposes of this writing we'll only consider the x64 platform. First up we'll look at our unmanaged matrix multiplication, which as we may recall is an SSE2 version. There some things we should note: this method cannot be inlined into the managed code, and there are no frame pointers (they got optimized out).
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