This is still a topological ordering such that every register class gets
a smaller enum value than its sub-classes.
Placing the smaller spill sizes first makes a difference for the
super-register class bit masks. When looking for a super-register class,
we usually want the smallest possible kind of super-register. That is
now available as the first bit set in the bit mask.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156222
91177308-0d34-0410-b5e6-
96231b3b80d8
if (A == B)
return 0;
- // Order by descending set size. Note that the classes' allocation order may
- // not have been computed yet. The Members set is always vaild.
- if (A->getMembers().size() > B->getMembers().size())
- return -1;
- if (A->getMembers().size() < B->getMembers().size())
- return 1;
-
// Order by ascending spill size.
if (A->SpillSize < B->SpillSize)
return -1;
if (A->SpillAlignment > B->SpillAlignment)
return 1;
+ // Order by descending set size. Note that the classes' allocation order may
+ // not have been computed yet. The Members set is always vaild.
+ if (A->getMembers().size() > B->getMembers().size())
+ return -1;
+ if (A->getMembers().size() < B->getMembers().size())
+ return 1;
+
// Finally order by name as a tie breaker.
return StringRef(A->getName()).compare(B->getName());
}