Re: Global restricted function pointer

Jacob Shamalini wrote:
) I have a trampoline variable into which I repeatedly load callbacks
) for execution, I'd like to be hopeful about it getting optimized into
) a register.
)
) More or less like this:
)
) void (*current_callback)();
)
) void run()
) {
) for(;;)
) current_callback(); // each callback loads a new callback as a
) side effect
) }
)
)
) I _can_ declare a global restricted object pointer, therefore I wonder
) if a function pointer might be legal.

I don't think 'restrict' does what you think it does.
And even if it did, you do *not* want it optimized into a register,
otherwise it could be calling the wrong function.

If you *want* it to be a register instead of a global pointer,
the following method could be useful:

void run()
{
void *(* cb)();
cb = init;
while (cb)
cb = cb();
}

I.E. each callback returns the next callback instead of
setting it in a global.

Note: the type definition of cb becomes quite tricky in this case,
so I decided to let the functions return void pointers which get
autoconverted to the correct function type by the assignment.


SaSW, Willem
--
Disclaimer: I am in no way responsible for any of the statements
made in the above text. For all I know I might be
drugged or something..
No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT
.

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