Jonas Maebe schreef:
On 8 nov 2006, at 17:46, Micha Nelissen wrote:
Is SSU easier to implement than SSA ?
No, it's a bit more work.
Aren't variables often more used than assigned (so more generated
variables by SSU) ?
Yes.
How do the achieved optimizations compare ?
SSU gives somewhat better results on register-starved architectures. The
change from SSA to SSU didn't make any difference for PPC for the
compiler+rtl (it can give a difference for large procedures with a lot
of variables which are used in different "phases" of course). It saves
about 5kb on the compiler on Linux/i386 compared to SSA-only.
Will you be working on SSA and/or SSU with control blocks (e.g. using
SSA in procedures where a for loop is used) before 2.2? Or will that be
released only in a later version.
A synthetic example that will benefit is the CalculatePoint procedure of
http://svn.freepascal.org/svn/fpc/trunk/tests/bench/shootout/src/mandelbrot.pp
Vincent
_______________________________________________
fpc-devel maillist - [email protected]
http://lists.freepascal.org/mailman/listinfo/fpc-devel
