Index: llvm/trunk/include/llvm/ADT/Triple.h
===================================================================
--- llvm/trunk/include/llvm/ADT/Triple.h
+++ llvm/trunk/include/llvm/ADT/Triple.h
@@ -214,8 +214,9 @@
     Itanium,
     Cygnus,
     CoreCLR,
-    Simulator,  // Simulator variants of other systems, e.g., Apple's iOS
-    LastEnvironmentType = Simulator
+    Simulator, // Simulator variants of other systems, e.g., Apple's iOS
+    MacCatalyst,
+    LastEnvironmentType = MacCatalyst
   };
   enum ObjectFormatType {
     UnknownObjectFormat,
@@ -485,6 +486,10 @@
     return getEnvironment() == Triple::Simulator;
   }
 
+  bool isMacCatalystEnvironment() const {
+    return getEnvironment() == Triple::MacCatalyst;
+  }
+
   bool isOSNetBSD() const {
     return getOS() == Triple::NetBSD;
   }
Index: llvm/trunk/lib/Support/Triple.cpp
===================================================================
--- llvm/trunk/lib/Support/Triple.cpp
+++ llvm/trunk/lib/Support/Triple.cpp
@@ -239,6 +239,7 @@
   case Cygnus: return "cygnus";
   case CoreCLR: return "coreclr";
   case Simulator: return "simulator";
+  case MacCatalyst: return "maccatalyst";
   }
 
   llvm_unreachable("Invalid EnvironmentType!");
@@ -541,6 +542,7 @@
     .StartsWith("cygnus", Triple::Cygnus)
     .StartsWith("coreclr", Triple::CoreCLR)
     .StartsWith("simulator", Triple::Simulator)
+    .StartsWith("maccatalyst", Triple::MacCatalyst)
     .Default(Triple::UnknownEnvironment);
 }
 
Index: llvm/trunk/unittests/ADT/TripleTest.cpp
===================================================================
--- llvm/trunk/unittests/ADT/TripleTest.cpp
+++ llvm/trunk/unittests/ADT/TripleTest.cpp
@@ -1237,6 +1237,17 @@
   EXPECT_EQ((unsigned)3, Minor);
   EXPECT_EQ((unsigned)0, Micro);
   EXPECT_TRUE(T.isSimulatorEnvironment());
+  EXPECT_FALSE(T.isMacCatalystEnvironment());
+
+  T = Triple("x86_64-apple-ios13.0-maccatalyst");
+  EXPECT_TRUE(T.isiOS());
+  T.getiOSVersion(Major, Minor, Micro);
+  EXPECT_EQ((unsigned)13, Major);
+  EXPECT_EQ((unsigned)0, Minor);
+  EXPECT_EQ((unsigned)0, Micro);
+  EXPECT_TRUE(T.getEnvironment() == Triple::MacCatalyst);
+  EXPECT_TRUE(T.isMacCatalystEnvironment());
+  EXPECT_FALSE(T.isSimulatorEnvironment());
 }
 
 TEST(TripleTest, FileFormat) {