where it's only bool-like 1/0 result like std::set.count().
Some of the LLVM ADT already return unsigned count(), while
others return bool count().
This patch modifies SmallPtrSet, SmallSet, SparseSet count()
to return unsigned instead of bool:
1 instead of true
0 instead of false
More ADT to follow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197879 91177308-0d34-0410-b5e6-96231b3b80d8
