diff --git a/utils/TableGen/NeonEmitter.cpp b/utils/TableGen/NeonEmitter.cpp
index 29930402daf..ac641b184e5 100644
--- a/utils/TableGen/NeonEmitter.cpp
+++ b/utils/TableGen/NeonEmitter.cpp
@@ -368,6 +368,52 @@ static std::string BuiltinTypeString(const char mod, StringRef typestr,
   return quad ? "V16c" : "V8c";
 }
 
+/// StructTag - generate the name of the struct tag for a type.
+/// These names are mandated by ARM's ABI.
+static std::string StructTag(StringRef typestr) {
+  bool quad = false;
+  bool poly = false;
+  bool usgn = false;
+  
+  // base type to get the type string for.
+  char type = ClassifyType(typestr, quad, poly, usgn);
+  
+  SmallString<128> s;
+  s += "__simd";
+  s += quad ? "128_" : "64_";
+  if (usgn)
+    s.push_back('u');
+  
+  switch (type) {
+    case 'c':
+      s += poly ? "poly8" : "int8";
+      break;
+    case 's':
+      s += poly ? "poly16" : "int16";
+      break;
+    case 'i':
+      s += "int32";
+      break;
+    case 'l':
+      s += "int64";
+      break;
+    case 'h':
+      s += "float16";
+      break;
+    case 'f':
+      s += "float32";
+      break;
+    default:
+      throw "unhandled type!";
+      break;
+  }
+
+  // Append _t, finishing the struct tag name.
+  s += "_t";
+  
+  return s.str();
+}
+
 /// MangleName - Append a type or width suffix to a base neon function name, 
 /// and insert a 'q' in the appropriate location if the operation works on
 /// 128b rather than 64b.   E.g. turn "vst2_lane" into "vst2q_lane_f32", etc.
@@ -878,10 +924,11 @@ void NeonEmitter::run(raw_ostream &OS) {
   // Emit struct typedefs.
   for (unsigned vi = 1; vi != 5; ++vi) {
     for (unsigned i = 0, e = TDTypeVec.size(); i != e; ++i) {
-      std::string ts = TypeString('d', TDTypeVec[i]);
-      std::string vs = (vi > 1) ? TypeString('0' + vi, TDTypeVec[i]) : ts;
-      OS << "typedef struct __" << vs << " {\n";
-      OS << "  __neon_" << ts << " val";
+      std::string ts = TypeString('d', TDTypeVec[i], vi == 1);
+      std::string vs = TypeString((vi > 1) ? '0' + vi : 'd', TDTypeVec[i]);
+      std::string tag = (vi > 1) ? vs : StructTag(TDTypeVec[i]);
+      OS << "typedef struct " << tag << " {\n";
+      OS << "  " << ts << " val";
       if (vi > 1)
         OS << "[" << utostr(vi) << "]";
       OS << ";\n} " << vs << ";\n\n";