The benchmarking summarized in
http://lists.llvm.org/pipermail/llvm-dev/2017-May/113525.html showed
this is beneficial for a wide range of cores.
As is to be expected, quite a few small adaptations are needed to the
regressions tests, as the difference in scheduling results in:
- Quite a few small instruction schedule differences.
- A few changes in register allocation decisions caused by different
instruction schedules.
- A few changes in IfConversion decisions, due to a difference in
instruction schedule and/or the estimated cost of a branch mispredict.
llvm-svn: 306514
The post-dominance property is not sufficient to guarantee that a restore point
inside a loop is safe.
E.g.,
while(1) {
Save
Restore
if (...)
break;
use/def CSRs
}
All the uses/defs of CSRs are dominated by Save and post-dominated
by Restore. However, the CSRs uses are still reachable after
Restore and before Save are executed.
This fixes PR25824
llvm-svn: 255613
Kristof Beyls