[LLVMdev] XOR Optimization

me22 me22.ca at gmail.com
Tue Jul 26 17:47:01 PDT 2011

2011/7/26 Daniel Nicácio <dnicacios at gmail.com>:
> I also would like to see why the "XOR  A,  -1" is not turned into a NOT, any

Probably because NOT (like NEG) doesn't exist :)


I assume the decision was made that it wasn't worth adding the extra
unary instructions when they can easily be handled in codegen by
matching "XOR X, -1" or "SUB 0, X".

~ Scott

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