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RE: Breakpoints


My question is still does GDB need to set more than one breakpoint when 
stepping through source? Thinking about it a little more GDB should have 
all of the information available to decide whether a branch will occur. It 
has the current value of all the registers (esp CCR) so it can work it out 
- the real question is does it use this information?

Dave.

----------
From: 	Mark Salter[SMTP:msalter@cygnus.com]
Sent: 	Thursday, December 23, 1999 2:09 AM
To: 	kevinb@cygnus.com
Cc: 	davidwilliams@ozemail.com.au; gdb@sourceware.cygnus.com
Subject: 	Re: Breakpoints

>>>>> Kevin Buettner writes:

> On Dec 22,  2:29pm, David Williams wrote:
>> Does GDB ever need to set more than one breakpoint when stepping through 
>> source code? I have not (as yet) seen this type of behaviour.

> Can the target do a singlestep in hardware or do you have to do
> software emulation?  If the latter, when you're stepping by machine
> instruction, you'd need two breakpoints on a conditional branch;
> one for the branch target, the other for the instruction after the
> branch.

Even in the latter case, the stub can evaluate the condition of the
branch to see which way its going to go.

--Mark




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