diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index 3111f5e385e..e9254c3d90c 100644
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -133,8 +133,13 @@ void ARMSubtarget::resetSubtargetFeatures(const MachineFunction *MF) {
 }
 
 void ARMSubtarget::resetSubtargetFeatures(StringRef CPU, StringRef FS) {
-  if (CPUString.empty())
-    CPUString = "generic";
+  if (CPUString.empty()) {
+    if (isTargetIOS() && TargetTriple.getArchName().endswith("v7s"))
+      // Default to the Swift CPU when targeting armv7s/thumbv7s.
+      CPUString = "swift";
+    else
+      CPUString = "generic";
+  }
 
   // Insert the architecture feature derived from the target triple into the
   // feature string. This is important for setting features that are implied
diff --git a/test/CodeGen/ARM/dagcombine-concatvector.ll b/test/CodeGen/ARM/dagcombine-concatvector.ll
index d8c6c645580..2927ea2f3ca 100644
--- a/test/CodeGen/ARM/dagcombine-concatvector.ll
+++ b/test/CodeGen/ARM/dagcombine-concatvector.ll
@@ -1,4 +1,4 @@
-; RUN: llc < %s -mtriple=thumbv7s-apple-ios3.0.0 | FileCheck %s
+; RUN: llc < %s -mtriple=thumbv7s-apple-ios3.0.0 -mcpu=generic | FileCheck %s
 
 ; PR15525
 ; CHECK-LABEL: test1: