[OrderedBasicBlock] Return false for comesBefore(A, A)

So far it would return true for the first uncached query, then cached
queries return false.

llvm-svn: 304545
diff --git a/llvm/lib/Analysis/OrderedBasicBlock.cpp b/llvm/lib/Analysis/OrderedBasicBlock.cpp
index 0f0016f..a04c0ae 100644
--- a/llvm/lib/Analysis/OrderedBasicBlock.cpp
+++ b/llvm/lib/Analysis/OrderedBasicBlock.cpp
@@ -55,7 +55,7 @@
   assert(II != IE && "Instruction not found?");
   assert((Inst == A || Inst == B) && "Should find A or B");
   LastInstFound = II;
-  return Inst == A;
+  return Inst != B;
 }
 
 /// \brief Find out whether \p A dominates \p B, meaning whether \p A