x64 Assembly and C++ Tutorial 45: MMX Boolean and Comparison Instructions 1

In this tutorial we'll look at all the remaining MMX instructions. They are Boolean and Comparison instructions. The Boolean instructions are very easy to grasp but the comparisons require a little practice (practise?).

Getting SIMD to perform branching is a trick. We create masks of 1's and 0's in binary with the comparison instructions. We then use boolean instructions to set the values we want. The next tutorial will show more clearly what this means.

I hope I've not bitten off more than is chewable by introducing both the boolean operations and comparisons. It's just that MMX comparisons aren't usable without the boolean operations.

Also my new microphone moves a little. The first half of the tute is louder than the second...

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