Re: gcc inlining heuristics was Re: [PATCH -v7][RFC]: mutex: implement adaptive spinning

Andi Kleen
2009-01-11T20:20:35Z

> Isn't the ioctl switch stack issue a separate GCC bug?
>
> It was/is assigning assigning separate space for local variables which

Was -- i think that got fixed in gcc. But again only in newer versions.

> are mutually exclusive. So instead of the stack footprint of the
> function with the switch() being equal to the largest individual stack
> size of all the subfunctions, it's equal to the _sum_ of the stack sizes
> of the subfunctions. Even though it'll never use them all at the same
> time.
>
> Without that bug, it would have been harmless to inline them all.

True.

-Andi
--
ak@linux.intel.com