rename isStore -> mayStore to more accurately reflect what it captures.

llvm-svn: 45656
diff --git a/llvm/lib/CodeGen/BranchFolding.cpp b/llvm/lib/CodeGen/BranchFolding.cpp
index 7e97223..9749162 100644
--- a/llvm/lib/CodeGen/BranchFolding.cpp
+++ b/llvm/lib/CodeGen/BranchFolding.cpp
@@ -353,7 +353,7 @@
     const TargetInstrDescriptor &TID = TII->get(I->getOpcode());
     if (TID.Flags & M_CALL_FLAG)
       Time += 10;
-    else if (TID.Flags & (M_LOAD_FLAG|M_STORE_FLAG))
+    else if (TID.Flags & (M_LOAD_FLAG|M_MAY_STORE_FLAG))
       Time += 2;
     else
       ++Time;