diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -222,7 +222,7 @@
     bool SinkInstruction(MachineInstr &MI, bool &SawStore,
                          AllSuccsCache &AllSuccessors);
 
-    /// If we sink a COPY inst, some debug users of it's destination may no
+    /// If we sink a COPY inst, some debug users of its destination may no
     /// longer be dominated by the COPY, and will eventually be dropped.
     /// This is easily rectified by forwarding the non-dominated debug uses
     /// to the copy source.
@@ -315,7 +315,7 @@
   if (MRI->use_nodbg_empty(Reg))
     return true;
 
-  // BreakPHIEdge is true if all the uses are in the successor MBB being sunken
+  // BreakPHIEdge is true if all the uses are in the successor MBB being sunk
   // into and they are all PHI nodes. In this case, machine-sink must break
   // the critical edge first. e.g.
   //