Re: [PATCH 4/4] trace: profile all if conditionals

[Ingo Molnar]

* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> 
> On Fri, 21 Nov 2008, Andrew Morton wrote:
> > >
> > > +#define if(cond) if (__builtin_constant_p((cond)) ? !!(cond) :		\
> > 
> > wheee...
> > 
> > Now how are you going to profile ?:, while, for(;expr;), etc? ;)

btw., there's hardware driven branch tracing and profiling in the 
works too, which captures all conditionals - including loops. Stay 
tuned :)

> I don't know. Give me a few months, I'll figure out a way ;-)

also loops generally have a more static (hence less interesting) 
prediction pattern - while for branches we frequently have a "should 
this branch be made likely/unlikely in the fastpath" question.

	Ingo
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