> i'm not sure what this means -- which of the transformations in that
It is not unsafe, just generates slight worse code.
current is inline assembler and the compiler doesn't know that it could
cache it in a register because it is not marked pure
for various reasons. That is why current is often cached explicitely
in a local variable to tell the compiler that.
Before you run off and do that everywhere: it is also not a large
win, just a small one unless current is used very often.
-Andi
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