Stop tracking spill slot uses in VirtRegMap.

Nobody cared, StackSlotColoring scans the instructions to find used stack
slots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144485 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveDebugVariables.cpp b/lib/CodeGen/LiveDebugVariables.cpp
index 3dfe4c0..0414692 100644
--- a/lib/CodeGen/LiveDebugVariables.cpp
+++ b/lib/CodeGen/LiveDebugVariables.cpp
@@ -889,8 +889,7 @@
       // index is no longer available. That means the user value is in a
       // non-existent sub-register, and %noreg is exactly what we want.
       Loc.substPhysReg(VRM.getPhys(VirtReg), TRI);
-    } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT &&
-               VRM.isSpillSlotUsed(VRM.getStackSlot(VirtReg))) {
+    } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT) {
       // FIXME: Translate SubIdx to a stackslot offset.
       Loc = MachineOperand::CreateFI(VRM.getStackSlot(VirtReg));
     } else {