[fpc-devel] More on arm4, armi and thumb

[Marco van de Voort]

> On 11/1/07, Marco van de Voort <marcov at stack.nl> wrote:
> > It seems that when you branch, in the instruction you can encode if the
> >  instructionset of the target is thumb or not.
> 
> So, currently fpc set's all branches to use arm4 mode
> 
> And C++ apps compiled could check what the system is using and use a
> if to either call in arm4 or call in thumb mode. The strange thing is
> that this is a bit arbitrary. There is nothing special about an OS
> call, it's just a call like any other. I wonder where does the
> compiler get the information of if the function is in arm4 or thumb
> mode.

I'd guess an attribute somewhere in the header. Either per function, or for
the header/lib as a whole.