Re: adding dependence from prefetch to load

[Jim Wilson <wilson at specifix dot com>]

George Caragea wrote:
> So my initial question remains: is there any way to tell the scheduler 
> not to place the prefetch instruction after the actual read?

You can try changing sched_analyze_2 in sched-deps.c to handle PREFETCH 
specially.

You could perhaps handle it similarly to how PRE_DEC is already handled, 
except that you don't have a MEM here which is an unfortunate 
complication.  You probably have to create a MEM RTL in order to pass it 
to sched_analyze_1.

Or you could try changing the representation of your prefetch insn rtl. 
 If you add an unspec_volatile to the pattern, you should get the 
dependency you want.
--
Jim Wilson, GNU Tools Support, http://www.specifix.com