Index: llvm/lib/Target/AMDGPU/SIPostRABundler.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/SIPostRABundler.cpp
+++ llvm/lib/Target/AMDGPU/SIPostRABundler.cpp
@@ -48,6 +48,9 @@
 
   SmallSet<Register, 16> Defs;
 
+  void collectUsedRegUnits(const MachineInstr &MI,
+                           BitVector &UsedRegUnits) const;
+
   bool isBundleCandidate(const MachineInstr &MI) const;
   bool isDependentLoad(const MachineInstr &MI) const;
   bool canBundle(const MachineInstr &MI, const MachineInstr &NextMI) const;
@@ -85,6 +88,21 @@
   return false;
 }
 
+void SIPostRABundler::collectUsedRegUnits(const MachineInstr &MI,
+                                          BitVector &UsedRegUnits) const {
+  for (const MachineOperand &Op : MI.operands()) {
+    if (!Op.isReg() || !Op.readsReg())
+      continue;
+
+    Register Reg = Op.getReg();
+    assert(!Op.getSubReg() &&
+           "subregister indexes should not be present after RA");
+
+    for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units)
+      UsedRegUnits.set(*Units);
+  }
+}
+
 bool SIPostRABundler::isBundleCandidate(const MachineInstr &MI) const {
   const uint64_t IMemFlags = MI.getDesc().TSFlags & MemFlags;
   return IMemFlags != 0 && MI.mayLoadOrStore() && !MI.isBundled();
@@ -107,6 +125,9 @@
     return false;
 
   TRI = MF.getSubtarget<GCNSubtarget>().getRegisterInfo();
+  BitVector BundleUsedRegUnits(TRI->getNumRegUnits());
+  BitVector KillUsedRegUnits(TRI->getNumRegUnits());
+
   bool Changed = false;
   for (MachineBasicBlock &MBB : MF) {
     MachineBasicBlock::instr_iterator Next;
@@ -150,6 +171,33 @@
       Next = std::next(BundleEnd);
       if (ClauseLength > 1) {
         Changed = true;
+
+        // Before register allocation, kills are inserted after potential soft
+        // clauses to hint register allocation. Look for kills that look like
+        // this, and erase them.
+        if (Next != E && Next->isKill()) {
+          MachineInstr &Kill = *Next;
+
+          for (const MachineInstr &BundleMI : make_range(BundleStart, Next))
+            collectUsedRegUnits(BundleMI, BundleUsedRegUnits);
+          collectUsedRegUnits(Kill, KillUsedRegUnits);
+
+          BundleUsedRegUnits.flip();
+          KillUsedRegUnits &= BundleUsedRegUnits;
+
+          // Erase the kill if it's a subset of the used registers.
+          //
+          // TODO: Should we just remove all kills? Is there any real reason to
+          // keep them after RA?
+          if (KillUsedRegUnits.none()) {
+            ++Next;
+            Kill.eraseFromParent();
+          }
+
+          BundleUsedRegUnits.reset();
+          KillUsedRegUnits.reset();
+        }
+
         finalizeBundle(MBB, BundleStart, Next);
       }
 
Index: llvm/test/CodeGen/AMDGPU/postra-bundle-memops.mir
===================================================================
--- llvm/test/CodeGen/AMDGPU/postra-bundle-memops.mir
+++ llvm/test/CodeGen/AMDGPU/postra-bundle-memops.mir
@@ -220,3 +220,61 @@
     $vgpr2 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
 
 ...
+
+# Before register allocation, KILL hints are inserted after potential soft
+# clauses to hint the register allocator to not clobber the input
+# registers. Kills that look like this should be erased.
+---
+name: post_bundle_kill
+body:             |
+  bb.0:
+    liveins: $vgpr3_vgpr4, $vgpr5_vgpr6
+
+    ; GCN-LABEL: name: post_bundle_kill
+    ; GCN: BUNDLE implicit-def $vgpr0, implicit-def $vgpr0_lo16, implicit-def $vgpr0_hi16, implicit-def $vgpr1, implicit-def $vgpr1_lo16, implicit-def $vgpr1_hi16, implicit $vgpr3_vgpr4, implicit $exec, implicit $vgpr5_vgpr6 {
+    ; GCN:   $vgpr0 = GLOBAL_LOAD_DWORD $vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    ; GCN:   $vgpr1 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
+    ; GCN: }
+    $vgpr0 = GLOBAL_LOAD_DWORD $vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    $vgpr1 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
+    KILL killed $vgpr3_vgpr4, killed $vgpr5_vgpr6
+...
+
+# Kill some other register not used in the bundle, should not be touched.
+---
+name: post_bundle_kill_other
+body:             |
+  bb.0:
+    liveins: $vgpr3_vgpr4, $vgpr5_vgpr6
+    ; GCN-LABEL: name: post_bundle_kill_other
+    ; GCN: $vgpr7 = V_MOV_B32_e32 0, implicit $exec
+    ; GCN: BUNDLE implicit-def $vgpr0, implicit-def $vgpr0_lo16, implicit-def $vgpr0_hi16, implicit-def $vgpr1, implicit-def $vgpr1_lo16, implicit-def $vgpr1_hi16, implicit $vgpr3_vgpr4, implicit $exec, implicit $vgpr5_vgpr6 {
+    ; GCN:   $vgpr0 = GLOBAL_LOAD_DWORD $vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    ; GCN:   $vgpr1 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
+    ; GCN: }
+    ; GCN: KILL killed $vgpr7
+    $vgpr7 = V_MOV_B32_e32 0, implicit $exec
+    $vgpr0 = GLOBAL_LOAD_DWORD $vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    $vgpr1 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
+    KILL killed $vgpr7
+...
+
+# Kill some other register not used in the bundle, but also some
+# from the bundle.
+---
+name: post_bundle_kill_plus_other
+body:             |
+  bb.0:
+    liveins: $vgpr3_vgpr4, $vgpr5_vgpr6
+    ; GCN-LABEL: name: post_bundle_kill_plus_other
+    ; GCN: $vgpr7 = V_MOV_B32_e32 0, implicit $exec
+    ; GCN: BUNDLE implicit-def $vgpr0, implicit-def $vgpr0_lo16, implicit-def $vgpr0_hi16, implicit-def $vgpr1, implicit-def $vgpr1_lo16, implicit-def $vgpr1_hi16, implicit $vgpr3_vgpr4, implicit $exec, implicit $vgpr5_vgpr6 {
+    ; GCN:   $vgpr0 = GLOBAL_LOAD_DWORD $vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    ; GCN:   $vgpr1 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
+    ; GCN: }
+    ; GCN: KILL killed $vgpr7, killed $vgpr3
+    $vgpr7 = V_MOV_B32_e32 0, implicit $exec
+    $vgpr0 = GLOBAL_LOAD_DWORD $vgpr3_vgpr4, 0, 0, 0, 0, implicit $exec
+    $vgpr1 = GLOBAL_LOAD_DWORD $vgpr5_vgpr6, 0, 0, 0, 0, implicit $exec
+    KILL killed $vgpr7, killed $vgpr3
+...