[globalisel][knownbits] Correct a typo that prevented a test working as intended

llvm-svn: 371115
diff --git a/llvm/unittests/CodeGen/GlobalISel/KnownBitsTest.cpp b/llvm/unittests/CodeGen/GlobalISel/KnownBitsTest.cpp
index 7f698ac..62d763b 100644
--- a/llvm/unittests/CodeGen/GlobalISel/KnownBitsTest.cpp
+++ b/llvm/unittests/CodeGen/GlobalISel/KnownBitsTest.cpp
@@ -19,7 +19,7 @@
   unsigned CopyReg = Copies[Copies.size() - 1];
   MachineInstr *FinalCopy = MRI->getVRegDef(CopyReg);
   unsigned SrcReg = FinalCopy->getOperand(1).getReg();
-  unsigned DstReg = FinalCopy->getOperand(1).getReg();
+  unsigned DstReg = FinalCopy->getOperand(0).getReg();
   GISelKnownBits Info(*MF);
   KnownBits Res = Info.getKnownBits(SrcReg);
   EXPECT_EQ((uint64_t)1, Res.One.getZExtValue());