GCC for i386 does several optimization 
to allow correct pairing of instructions.

   This leads in particular to mix loading of constants into registers
with usual prologue instructions.

   The major effect is that the backtrace shows some 
'pseudo' trace levels, which are due to a failure to get
the correct prologue.
  One of the nastiest effect of this is that
if you use 'return' on that function, it sets a temporary
breakpoint on a wrong location and you program
continues without stopping when frame is left.


   I started to implement some code that tries to deal with that issue.
Its far from perfect, but it gives already some result
(when debugging GDB with itself compiled with -O2,
it reduces the number of those false frame levels).

This code might probably be used at several other position.

   All comments and suggestions welcome.

2001-12-02  Pierre Muller  <muller@ics.u-strasbg.fr>

          * i386-tdep.c (i386_skip_optimization_code): New function used to
	skip over code inserted by optimizer.
	(i386_get_frame_setup): Use i386_skip_optimization_code to 
	enhance prologue detection.