Index: lib/Target/ARM/ARMFrameLowering.cpp
===================================================================
--- lib/Target/ARM/ARMFrameLowering.cpp
+++ lib/Target/ARM/ARMFrameLowering.cpp
@@ -1537,14 +1537,20 @@
   MachineRegisterInfo &MRI = MF.getRegInfo();
   unsigned FramePtr = RegInfo->getFrameRegister(MF);
 
-  // Spill R4 if Thumb2 function requires stack realignment - it will be used as
-  // scratch register. Also spill R4 if Thumb2 function has varsized objects,
-  // since it's not always possible to restore sp from fp in a single
-  // instruction.
-  // FIXME: It will be better just to find spare register here.
-  if (AFI->isThumb2Function() &&
-      (MFI->hasVarSizedObjects() || RegInfo->needsStackRealignment(MF)))
-    SavedRegs.set(ARM::R4);
+  if (AFI->isThumb2Function()) {
+    // Spill R4 if Thumb2 function requires stack realignment - it will be used as
+    // scratch register. Also spill R4 if Thumb2 function has varsized objects,
+    // since it's not always possible to restore sp from fp in a single
+    // instruction.
+    // FIXME: It will be better just to find spare register here.
+    if (MFI->hasVarSizedObjects() || RegInfo->needsStackRealignment(MF))
+      SavedRegs.set(ARM::R4);
+
+    // If the current function is noreturn and has calls it must preserve
+    // ARM::LR in order to guarantee sane backtraces.
+    if (AFI->shouldForceLRSpill())
+      SavedRegs.set(ARM::LR);
+  }
 
   if (AFI->isThumb1OnlyFunction()) {
     // Spill LR if Thumb1 function uses variable length argument lists.
Index: lib/Target/ARM/ARMISelLowering.cpp
===================================================================
--- lib/Target/ARM/ARMISelLowering.cpp
+++ lib/Target/ARM/ARMISelLowering.cpp
@@ -1827,6 +1827,10 @@
       CallOpc = ARMISD::CALL_NOLINK;
     else
       CallOpc = isARMFunc ? ARMISD::CALL : ARMISD::tCALL;
+    // If the current function is noreturn and has direct calls it must preserve
+    // ARM::LR in order to guarantee sane backtraces.
+    if (!isARMFunc && doesNotRet && isDirect)
+      AFI->setForceLRSpill(true);
   } else {
     if (!isDirect && !Subtarget->hasV5TOps())
       CallOpc = ARMISD::CALL_NOLINK;
Index: lib/Target/ARM/ARMMachineFunctionInfo.h
===================================================================
--- lib/Target/ARM/ARMMachineFunctionInfo.h
+++ lib/Target/ARM/ARMMachineFunctionInfo.h
@@ -59,6 +59,11 @@
   /// emitPrologue.
   bool RestoreSPFromFP;
 
+  /// ForceLRSpill - True if the LR register needs to be spilled. This is
+  /// necessary to force LR spill in noreturn function and is used in
+  /// processFunctionBeforeCalleeSavedScan().
+  bool ForceLRSpill;
+
   /// LRSpilledForFarJump - True if the LR register has been for spilled to
   /// enable far jump.
   bool LRSpilledForFarJump;
@@ -128,7 +133,7 @@
     isThumb(false),
     hasThumb2(false),
     ArgRegsSaveSize(0), ReturnRegsCount(0), HasStackFrame(false),
-    RestoreSPFromFP(false),
+    RestoreSPFromFP(false), ForceLRSpill(false),
     LRSpilledForFarJump(false),
     FramePtrSpillOffset(0), GPRCS1Offset(0), GPRCS2Offset(0), DPRCSOffset(0),
     GPRCS1Size(0), GPRCS2Size(0), DPRCSAlignGapSize(0), DPRCSSize(0),
@@ -156,6 +161,9 @@
   bool shouldRestoreSPFromFP() const { return RestoreSPFromFP; }
   void setShouldRestoreSPFromFP(bool s) { RestoreSPFromFP = s; }
 
+  bool shouldForceLRSpill() const { return ForceLRSpill; }
+  void setForceLRSpill(bool s) { ForceLRSpill = s; }
+
   bool isLRSpilledForFarJump() const { return LRSpilledForFarJump; }
   void setLRIsSpilledForFarJump(bool s) { LRSpilledForFarJump = s; }
 
Index: test/CodeGen/Thumb2/call-noret-direct.ll
===================================================================
--- /dev/null
+++ test/CodeGen/Thumb2/call-noret-direct.ll
@@ -0,0 +1,21 @@
+;RUN: llc < %s -mtriple=thumbv7-apple-ios | FileCheck %s
+
+define void @a() noreturn nounwind ssp {
+; CHECK-LABEL: _a:
+; CHECK: push {r7, lr}
+; CHECK-NEXT: mov r7, sp
+; CHECK-NEXT: bl _b
+  tail call void @b()
+  unreachable
+}
+
+define void @b() noreturn nounwind ssp {
+; CHECK-LABEL: _b:
+; CHECK: push {r7, lr}
+; CHECK-NEXT: mov r7, sp
+; CHECK-NEXT: blx _abort
+  tail call void @abort() noreturn nounwind
+  unreachable
+}
+
+declare void @abort() noreturn