Re: Kernel 2.6 size increase - get_current()?

From: Ihar \ (filia@softhome.net)
Date: Mon Jul 28 2003 - 03:14:17 EST


Miles Bader wrote:
> Hollis Blanchard <hollisb@us.ibm.com> writes:
>
>>Inlines don't always help performance (depending on cache sizes, branch
>>penalties, frequency of code access...), but they do always increase
>>code size.
>
>
> Um, inlining can often _decrease_ code size because it gives the
> compiler substantial new opportunities for optimization (the function
> body is no longer opaque, so the compiler has a lot more info, and any
> optimizations done on the inlined body can be context-specific).
>

   starting from -O3 gcc do always trys to do inlining.
   was observed on gcc 3.2 and I beleive I saw the same 2.95.3

   compile this test with 02 & 03:
-------------------
#include <stdio.h>

int aaa() { return 32; }

int main() {
         int b = aaa();
         printf("hello %d \n", b);
         return 0;
}
------------------

    and then objdump -d to see the difference between main()s: 02 - you
will see function call, 03 - you will see just raw number 0x20 used.

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