Re: [stella] Stella Debugger RFC

Subject: Re: [stella] Stella Debugger RFC
From: Thomas Jentzsch <tjentzsch@xxxxxx>
Date: Wed, 15 Jun 2005 17:01:40 -0400
Erik Mooney wrote:
>>Can anyone think of a better way to implement this? Should I be watching
>>the stack pointer instead? Or should I actually be looking for an RTS
>>instruction, maybe?

> Why not have the trace execution stop upon reaching _either_ the target
> PC or an RTS instruction?  Neither method by itself is foolproof. There's
> a few code cases where a subroutine modifies its return address on the
> stack which would miss your target PC.  And looking for an RTS isn't 100%
> reliable either as some subroutines manually reset the stack pointer then
> JMP or Bxx based on a known flag (sometimes this can be faster than RTS.)

How about watching the stack pointer (too)?

Have fun!
Thomas                            
_______________________________________________________
Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |

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