[bfin] Don't load the address of counter variable before calling _mcount ()

[Bernd Schmidt]

Jie Zhang wrote:
> To load the address of counter variable may clobber the value of P1, 
> which is set up in function prologue, since the instrument code is 
> inserted after prologue. To fix it, we could save P1 on stack before 
> loading the address of counter variable into P1 and pop it from stack 
> after _mcount return. But there is only one project using -pg on 
> Blackfin and it does not require the address of counter variable, so the 
> simpler way is not to load the address into P1 at all.

Maybe we could just define PROFILE_BEFORE_PROLOGUE?


Bernd