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Re: How can I do calling for external address in my "C" programm by inline GAS?

Ian wrote:
> Dmitrij K <> writes:
> > 7       asm volatile (
> > 8           "movq %0, %%rcx;" /* str into RCX is first integer argument
> > (amd64 notation) */
> > 9           "movq %1, %%rdi;" /* address of PRINTF into RDI is Must be
> > preserved by called function (amd64 notation) */
> > 10          "call * %%rdi;" /* call PRINTF */
> > 11       :  /* no output */
> > 12       :"r"(str),"r"(p_printf)         /* input */
> > 13       : "rcx", "rdi", "memory" /* clobbered register */
> > 14      );
> > 15      }
> On x86_64 the first parameter should go into %rdi, not %rcx.  You are
> putting the function address into %rdi, so in effect you are treating
> the function address as a printf format string.
> Ian

Thanks for your reply.

I did as you told me, but it is not working too :( (I had used %r15 instead 
%rdi for p_printf, and %rdi for str)...

I have not ideas how I can to call func by the address.
I can't find examples of calling functions with args by address (as needs me).
I had seen examples without args only (abi, internet)...
I need help still.

Maybe you have a something tips/examples for me ?

PS: Sorry, but I have not an experience of programming on assembler (excluding 
2-3 programms "hello world" for GAS 32 bit) . I have some experience of 
programming on c/c++ only (And I'm away from proff, I'm an amateur, and I'm 
doing it for myself).

The best Regards.

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