ScheduleDAGInstrs: When adding uses we add them into a set that's empty at the beginning, no need to maintain another set for the added regs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152934 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/ScheduleDAGInstrs.cpp b/lib/CodeGen/ScheduleDAGInstrs.cpp
index 1c455b9..6be1ab7 100644
--- a/lib/CodeGen/ScheduleDAGInstrs.cpp
+++ b/lib/CodeGen/ScheduleDAGInstrs.cpp
@@ -209,13 +209,13 @@
   } else {
     // For others, e.g. fallthrough, conditional branch, assume the exit
     // uses all the registers that are livein to the successor blocks.
-    SmallSet<unsigned, 8> Seen;
+    assert(Uses.empty() && "Uses in set before adding deps?");
     for (MachineBasicBlock::succ_iterator SI = BB->succ_begin(),
            SE = BB->succ_end(); SI != SE; ++SI)
       for (MachineBasicBlock::livein_iterator I = (*SI)->livein_begin(),
              E = (*SI)->livein_end(); I != E; ++I) {
         unsigned Reg = *I;
-        if (Seen.insert(Reg))
+        if (!Uses.contains(Reg))
           Uses[Reg].push_back(&ExitSU);
       }
   }