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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92883 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 4 insertions, 0 deletions

diff --git a/include/llvm/CodeGen/MachineFunction.h b/include/llvm/CodeGen/MachineFunction.h
index f1bfa01458..a12a55aefc 100644
--- a/include/llvm/CodeGen/MachineFunction.h
+++ b/include/llvm/CodeGen/MachineFunction.h
@@ -315,6 +315,8 @@ public:
   /// 'Orig' instruction, identical in all ways except the the instruction
   /// has no parent, prev, or next.
   ///
+  /// See also TargetInstrInfo::duplicate() for target-specific fixes to cloned
+  /// instructions.
   MachineInstr *CloneMachineInstr(const MachineInstr *Orig);
 
   /// DeleteMachineInstr - Delete the given MachineInstr.
diff --git a/include/llvm/Target/TargetInstrInfo.h b/include/llvm/Target/TargetInstrInfo.h
index f7798018b5..0494ffe592 100644
--- a/include/llvm/Target/TargetInstrInfo.h
+++ b/include/llvm/Target/TargetInstrInfo.h
@@ -235,6 +235,8 @@ public:
   /// duplicate - Create a duplicate of the Orig instruction in MF. This is like
   /// MachineFunction::CloneMachineInstr(), but the target may update operands
   /// that are required to be unique.
+  ///
+  /// The instruction must be duplicable as indicated by isNotDuplicable().
   virtual MachineInstr *duplicate(MachineInstr *Orig,
                                   MachineFunction &MF) const = 0;