diff --git a/llvm/include/llvm/Target/TargetMachine.h b/llvm/include/llvm/Target/TargetMachine.h
--- a/llvm/include/llvm/Target/TargetMachine.h
+++ b/llvm/include/llvm/Target/TargetMachine.h
@@ -502,6 +502,9 @@
   /// The default variant to use in unqualified `asm` instructions.
   /// If this returns 0, `asm "$(foo$|bar$)"` will evaluate to `asm "foo"`.
   virtual int unqualifiedInlineAsmVariant() const { return 0; }
+
+  // MachineRegisterInfo callback function
+  virtual void registerMachineRegisterInfoCallback(MachineFunction &MF) const {}
 };
 
 /// Helper method for getting the code model, returning Default if
diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp
--- a/llvm/lib/CodeGen/MachineModuleInfo.cpp
+++ b/llvm/lib/CodeGen/MachineModuleInfo.cpp
@@ -106,6 +106,10 @@
     const TargetSubtargetInfo &STI = *TM.getSubtargetImpl(F);
     MF = new MachineFunction(F, TM, STI, NextFnNum++, *this);
     MF->initTargetMachineFunctionInfo(STI);
+
+    // MRI callback for target specific initializations.
+    TM.registerMachineRegisterInfoCallback(*MF);
+
     // Update the set entry.
     I.first->second.reset(MF);
   } else {
diff --git a/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp b/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp
--- a/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp
+++ b/llvm/lib/CodeGen/ResetMachineFunctionPass.cpp
@@ -22,6 +22,7 @@
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/InitializePasses.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Target/TargetMachine.h"
 using namespace llvm;
 
 #define DEBUG_TYPE "reset-machine-function"
@@ -68,6 +69,10 @@
         MF.reset();
         MF.initTargetMachineFunctionInfo(MF.getSubtarget());
 
+        const LLVMTargetMachine &TM = MF.getTarget();
+        // MRI callback for target specific initializations.
+        TM.registerMachineRegisterInfoCallback(MF);
+
         if (EmitFallbackDiag) {
           const Function &F = MF.getFunction();
           DiagnosticInfoISelFallback DiagFallback(F);