Index: include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h
===================================================================
--- include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h
+++ include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h
@@ -84,13 +84,15 @@
     addUseFromArg(MIB, Arg1);
     addUsesFromArgs(MIB, std::forward<UseArgsTy>(Args)...);
   }
+
+  bool InsertAfter;
 public:
   /// Some constructors for easy use.
   MachineIRBuilder() = default;
   MachineIRBuilder(MachineFunction &MF) { setMF(MF); }
-  MachineIRBuilder(MachineInstr &MI)
+  MachineIRBuilder(MachineInstr &MI, bool InsertAfter = false)
       : MachineIRBuilder(*MI.getParent()->getParent()) {
-    setInstr(MI);
+    setInstr(MI, InsertAfter);
   }
 
   /// Getter for the function we currently build.
@@ -113,7 +115,7 @@
   /// Set the insertion point before the specified position.
   /// \pre MBB must be in getMF().
   /// \pre II must be a valid iterator in MBB.
-  void setInsertPt(MachineBasicBlock &MBB, MachineBasicBlock::iterator II);
+  void setInsertPt(MachineBasicBlock &MBB, MachineBasicBlock::iterator II, bool InsertAfter = false);
   /// @}
 
   /// \name Setters for the insertion point.
@@ -127,7 +129,7 @@
 
   /// Set the insertion point to before MI.
   /// \pre MI must be in getMF().
-  void setInstr(MachineInstr &MI);
+  void setInstr(MachineInstr &MI, bool InsertAfter = false);
   /// @}
 
   /// \name Control where instructions we create are recorded (typically for
Index: lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
===================================================================
--- lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
+++ lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
@@ -39,18 +39,21 @@
          "Basic block is in a different function");
 }
 
-void MachineIRBuilder::setInstr(MachineInstr &MI) {
+void MachineIRBuilder::setInstr(MachineInstr &MI, bool InsertAfter) {
   assert(MI.getParent() && "Instruction is not part of a basic block");
   setMBB(*MI.getParent());
   this->II = MI.getIterator();
+  this->InsertAfter = InsertAfter;
 }
 
 void MachineIRBuilder::setInsertPt(MachineBasicBlock &MBB,
-                                   MachineBasicBlock::iterator II) {
+                                   MachineBasicBlock::iterator II,
+                                   bool InsertAfter) {
   assert(MBB.getParent() == &getMF() &&
          "Basic block is in a different function");
   this->MBB = &MBB;
   this->II = II;
+  this->InsertAfter = InsertAfter;
 }
 
 void MachineIRBuilder::recordInsertions(
@@ -77,7 +80,12 @@
 
 
 MachineInstrBuilder MachineIRBuilder::insertInstr(MachineInstrBuilder MIB) {
-  getMBB().insert(getInsertPt(), MIB);
+  auto &MBB = getMBB();
+  if (!InsertAfter)
+    MBB.insert(getInsertPt(), MIB);
+  else
+    MBB.insertAfter(getInsertPt(), MIB);
+
   if (InsertedInstr)
     InsertedInstr(MIB);
   return MIB;