[C++11] Remove the completely unnecessary requirement on SetVector's

remove_if that its predicate is adaptable. We don't actually need this,
we can write a generic adapter for any predicate.

This lets us remove some very wrong std::function usages. We should
never be using std::function for predicates to algorithms. This incurs
an *indirect* call overhead for every evaluation of the predicate, and
makes it very hard to inline through.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202742 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/SROA.cpp

@@ -3640,7 +3640,7 @@ bool SROA::runOnFunction(Function &F) {
       // Remove the deleted allocas from various lists so that we don't try to
       // continue processing them.
       if (!DeletedAllocas.empty()) {
-        std::function<bool(AllocaInst *)> IsInSet = [&](AllocaInst *AI) {
+        auto IsInSet = [&](AllocaInst *AI) {
           return DeletedAllocas.count(AI);
         };
         Worklist.remove_if(IsInSet);