Parallel execution

[Ian Lance Taylor]

Hasan MUTLU <bigpatboy@yahoo.com> writes:

> I have implemented a multiprocessor system and want to run a code on my system. 
> My idea is to have a compiler support that tells me which instructions could be 
> executed in parallel without any problems. In other words, I have a given code 
> that is written without considering any kind of parallelization (a standard C 
> code written for single processor) and I want my compiler to tell me which 
> instructions don't have any kind of dependencies, so could be run in parallel. 
> This might remind you VLIW, which deals more or less with the same problem. You 
> can ignore how my hardware deals with this information. My question is how close 
> I can get to this information with gcc compiler. In other words, how can I 
> determine instruction dependencies, the instructions that could be run in 
> parallel? Any command line options (if there is) or a pointer in the source code 
> of gcc would be helpful. 

gcc doesn't support this directly.  You can get the information by using
-fdump-rtl-sched2.  Also fiddle with -fsched-verbose=N.

Ian