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Date: Tue, 18 Dec 2007 02:27:00 -0000
From: Jonathan Adamczewski <jadamcze@utas.edu.au>
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To: trevor_smigiel@playstation.sony.com
CC: gcc <gcc@gcc.gnu.org>, Ulrich Weigand <uweigand@de.ibm.com>,   Russell_Olsen@playstation.sony.com
Subject: Re: __builtin_expect for indirect function calls
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trevor_smigiel@playstation.sony.com wrote:
> Are there any comments about the name, semantics, or usefulness of this
> extension?
>   

Sounds very useful for SPU code. I look forward to trying it out.


Toying with the idea, the following seems like a potentially useful C++
form of the proposed extension :

struct A {
virtual void foo();
};

struct B : public A {
virtual void foo();
};

A* a;

...

__builtin_expect_call (a->foo, B::foo)();



jonathan.