In C, would !~b ever be faster than b == 0xff ?
- by James Morris
From a long time ago I have a memory which has stuck with me that says comparisons against zero are faster than any other value (ahem Z80).
In some C code I'm writing I want to skip values which have all their bits set. Currently the type of these values is char but may change. I have two different alternatives to perform the test:
if (!~b)
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