Index: llvm/trunk/lib/CodeGen/GlobalISel/IRTranslator.cpp
===================================================================
--- llvm/trunk/lib/CodeGen/GlobalISel/IRTranslator.cpp
+++ llvm/trunk/lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -1564,7 +1564,9 @@
     Args.push_back(getOrCreateVRegs(*Arg));
   }
 
-  MF->getFrameInfo().setHasCalls(true);
+  // We don't set HasCalls on MFI here yet because call lowering may decide to
+  // optimize into tail calls. Instead, we defer that to selection where a final
+  // scan is done to check if any instructions are calls.
   bool Success =
       CLI->lowerCall(MIRBuilder, CS, Res, Args, SwiftErrorVReg,
                      [&]() { return getOrCreateVReg(*CS.getCalledValue()); });
Index: llvm/trunk/lib/CodeGen/GlobalISel/InstructionSelect.cpp
===================================================================
--- llvm/trunk/lib/CodeGen/GlobalISel/InstructionSelect.cpp
+++ llvm/trunk/lib/CodeGen/GlobalISel/InstructionSelect.cpp
@@ -17,7 +17,9 @@
 #include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
 #include "llvm/CodeGen/GlobalISel/Utils.h"
 #include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetInstrInfo.h"
 #include "llvm/CodeGen/TargetLowering.h"
 #include "llvm/CodeGen/TargetPassConfig.h"
 #include "llvm/CodeGen/TargetSubtargetInfo.h"
@@ -223,6 +225,22 @@
   auto &TLI = *MF.getSubtarget().getTargetLowering();
   TLI.finalizeLowering(MF);
 
+  // Determine if there are any calls in this machine function. Ported from
+  // SelectionDAG.
+  MachineFrameInfo &MFI = MF.getFrameInfo();
+  for (const auto &MBB : MF) {
+    if (MFI.hasCalls() && MF.hasInlineAsm())
+      break;
+
+    for (const auto &MI : MBB) {
+      if ((MI.isCall() && !MI.isReturn()) || MI.isStackAligningInlineAsm())
+        MFI.setHasCalls(true);
+      if (MI.isInlineAsm())
+        MF.setHasInlineAsm(true);
+    }
+  }
+
+
   LLVM_DEBUG({
     dbgs() << "Rules covered by selecting function: " << MF.getName() << ":";
     for (auto RuleID : CoverageInfo.covered())
Index: llvm/trunk/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
===================================================================
--- llvm/trunk/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ llvm/trunk/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -364,8 +364,6 @@
   auto &TLI = *MIRBuilder.getMF().getSubtarget().getTargetLowering();
   const char *Name = TLI.getLibcallName(Libcall);
 
-  MIRBuilder.getMF().getFrameInfo().setHasCalls(true);
-
   CallLowering::CallLoweringInfo Info;
   Info.CallConv = TLI.getLibcallCallingConv(Libcall);
   Info.Callee = MachineOperand::CreateES(Name);
@@ -430,7 +428,6 @@
   const char *Name = TLI.getLibcallName(RTLibcall);
 
   MIRBuilder.setInstr(MI);
-  MIRBuilder.getMF().getFrameInfo().setHasCalls(true);
 
   CallLowering::CallLoweringInfo Info;
   Info.CallConv = TLI.getLibcallCallingConv(RTLibcall);
Index: llvm/trunk/test/CodeGen/AArch64/GlobalISel/call-translator.ll
===================================================================
--- llvm/trunk/test/CodeGen/AArch64/GlobalISel/call-translator.ll
+++ llvm/trunk/test/CodeGen/AArch64/GlobalISel/call-translator.ll
@@ -100,7 +100,6 @@
 }
 
 ; CHECK-LABEL: name: test_arr_call
-; CHECK: hasCalls: true
 ; CHECK: %0:_(p0) = COPY $x0
 ; CHECK: [[LD1:%[0-9]+]]:_(s64) = G_LOAD %0(p0) :: (load 8 from %ir.addr)
 ; CHECK: [[CST1:%[0-9]+]]:_(s64) = G_CONSTANT i64 8
Index: llvm/trunk/test/CodeGen/AArch64/GlobalISel/tail-call-no-save-fp-lr.ll
===================================================================
--- llvm/trunk/test/CodeGen/AArch64/GlobalISel/tail-call-no-save-fp-lr.ll
+++ llvm/trunk/test/CodeGen/AArch64/GlobalISel/tail-call-no-save-fp-lr.ll
@@ -0,0 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc %s -verify-machineinstrs -mtriple aarch64-apple-darwin -global-isel -global-isel-abort=1 -o - 2>&1 | FileCheck %s
+
+; Check that we get a tail call to foo without saving fp/lr.
+define void @bar(i32 %a) #1 {
+; CHECK-LABEL: bar:
+; CHECK:       ; %bb.0: ; %entry
+; CHECK-NEXT:    b _zoo
+entry:
+  tail call void @zoo(i32 undef)
+  ret void
+}
+
+define void @zoo(i32 %a) {
+entry:
+  ret void
+}
+
+attributes #1 = { "frame-pointer"="all" }
+