On Mon, 2015-04-06 at 08:40 +0200, Nicholas Mc Guire wrote:
> #define msecs_to_jiffies(m) \
> (__builtin_constant_p (m) \
> ? ((m) * HZ / MSECS_PER_SEC ) : __msecs_to_jiffies(m))
[]
> main:
> .LFB12:
> .cfi_startproc
> subq $8, %rsp #,
> .cfi_def_cfa_offset 16
> movl $10, %esi #,
> movl $.LC0, %edi #,
> xorl %eax, %eax #
> call printf #
vs:
> static inline unsigned long msecs_to_jiffies(int m)
> {
> return __builtin_constant_p (m) ?
> (m) * HZ / MSECS_PER_SEC : __msecs_to_jiffies(m);
> }
[]
> main:
> .LFB13:
> .cfi_startproc
> subq $8, %rsp #,
> .cfi_def_cfa_offset 16
> xorl %esi, %esi #
> movl $.LC0, %edi #,
> xorl %eax, %eax #
> call printf #
>
> giving it another run from scratch somewhere I simply screwed up or
> overlooked some detail.
If the optimizer was doing it's job properly, wouldn't
the macro and inline output object code be the same?
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