c - Should I remove unnecessary `else` in `else if`? -

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compare two: 

if (strstr(a, "earth"))     // a1     return x; if (strstr(a, "ear"))       // a2     return y;

and

if (strstr(a, "earth"))     // b1     return x; else if (strstr(a, "ear"))  // b2     return y;

personally, feel else redundant , prevent cpu branch prediction.

in first one, when executing a1, it's possible pre-decode a2. , in second one, not interpret b2 until b1 evaluated false.

i found lot of (maybe of?) sources using latter form. though, latter form looks better understand, because it's not call return y if a =~ /ear(?!th)/ without else clause.

your compiler knows both these examples mean same thing. cpu branch prediction doesn't come it.

i choose first option symmetry.


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