Re: Status of CONFIG_FORCED_INLINING?

Adrian Bunk
2007-05-24T17:13:17Z

On Wed, May 23, 2007 at 02:31:33PM -0700, Arjan van de Ven wrote:
> Adrian Bunk wrote:
>> What about performance reasons?
>> We habe "inline" code in header files that heavily relies on being nearly
>> completely optimized away after being inlined.
>
> fair
>
>> Especially with -Os it could even sound logical for a compiler to never
>> inline a non-forced "inline"'d three line function with 2 callers.
>
> but you said "I Care about size more than performance". Your argument is
> thus absolutely incorrect.

Theoretically, you are right.

Practically, this would imply removing the CONFIG_CC_OPTIMIZE_FOR_SIZE
option several distributions currently enable by default since it has
been shown that it often generates faster code...

>> The rules are simple:
>> - every static function in a header file must be __always_inline
>
> wrong.
>
>> Your suggestion is possible, but please also send a patch that turns every
>> "inline" in header files into __always_inline...
>
> this is 1) insane and 2) if inlines in headers are so big gcc decides to
> not inline them.. they're too big and don't belong in the header.

Exactly.

So there's no point in having a non-forced inline.

cu
Adrian

--

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"Only a promise," Lao Er said.
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