diff --git a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
--- a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -1175,7 +1175,7 @@
   // destination register as well.
   if (Reg0 == Reg1) {
     // Must be two address instruction!
-    assert(MI.getDesc().getOperandConstraint(0, MCOI::TIED_TO) &&
+    assert(MI.getDesc().getOperandConstraint(1, MCOI::TIED_TO) == 0 &&
            "Expecting a two-address instruction!");
     assert(MI.getOperand(0).getSubReg() == SubReg1 && "Tied subreg mismatch");
     Reg2IsKill = false;