stack frame optimization problem

[Vladimir Panteleev]

On Tue, 20 Oct 2009 18:45:50 +0300, sprucely <timberdig at gmail.com> wrote:

> This works with g++ and inline ATT assembly, but I have had no such luck  
> in D. I have many simple functions that need to be executed sequentially  
> and have identical stack frames. To avoid the overhead of setting up and  
> tearing down the stack frames I want to jmp from the body of one  
> function to the body of the next. A simplified example...
>
> extern(C) byte jumpHere;
>
> byte* jumpTo = &jumpHere;
>
> void f1()
> {
> 	asm
> 	{
> 		//jmp dword ptr jumpTo;
> 		mov EAX, jumpTo;
> 		jmp EAX;
> 		//jmp [EAX]
> 	}
> }
>
> void f2()
> {
> 	asm{jumpHere:;}
> }
>
> No matter what I try I get a segfault. My assembly skills are very  
> limited. I'm not using the naked keyword yet, because I want to get a  
> proof-of-concept working first. Anyone see anything wrong with this? Any  
> suggestions?

Just disassemble the resulting machine code and look at what's going on.

-- 
Best regards,
  Vladimir                          mailto:thecybershadow at gmail.com