Index: lib/Format/Format.cpp
===================================================================
--- lib/Format/Format.cpp
+++ lib/Format/Format.cpp
@@ -1386,6 +1386,7 @@
   LangOpts.CPlusPlus = 1;
   LangOpts.CPlusPlus11 = Style.Standard == FormatStyle::LS_Cpp03 ? 0 : 1;
   LangOpts.CPlusPlus14 = Style.Standard == FormatStyle::LS_Cpp03 ? 0 : 1;
+  LangOpts.CUDA = Style.Language == FormatStyle::LK_Cpp ? 1 : 0;
   LangOpts.LineComment = 1;
   bool AlternativeOperators = Style.Language != FormatStyle::LK_JavaScript &&
                               Style.Language != FormatStyle::LK_Java;
Index: lib/Format/TokenAnnotator.cpp
===================================================================
--- lib/Format/TokenAnnotator.cpp
+++ lib/Format/TokenAnnotator.cpp
@@ -63,6 +63,20 @@
         next();
         return true;
       }
+      if (CurrentToken->is(tok::greatergreatergreater)) {
+        // Treat >>> as 3 tokens in this context
+        static int Count;
+        if (Count == 0) Count = 3;
+
+        Left->MatchingParen = CurrentToken;
+        CurrentToken->MatchingParen = Left;
+        CurrentToken->Type = TT_TemplateCloser;
+        --Count;
+
+        // Only increment parser if 3 calls have been made
+        if (Count == 0) next();
+        return true;
+      }
       if (CurrentToken->is(tok::question) &&
           Style.Language == FormatStyle::LK_Java) {
         next();
@@ -1792,6 +1806,18 @@
              Left.isOneOf(TT_TemplateCloser, TT_TemplateOpener));
   if ((Left.is(TT_TemplateOpener)) != (Right.is(TT_TemplateCloser)))
     return Style.SpacesInAngles;
+  // Treat parameters in between <<< and >>> similar to template parameters
+  if (Left.is(tok::lesslessless) && Right.isNot(tok::greatergreatergreater))
+    return Style.SpacesInAngles;
+  if (Right.is(tok::greatergreatergreater))
+    return Style.SpacesInAngles;
+  // No space needed between identifier or ">" and "<<<".
+  if ((Left.is(tok::identifier) || Left.is(tok::greater)) &&
+      Right.is(tok::lesslessless))
+    return false;
+  // No space needed between ">>>" and "("
+  if (Left.is(tok::greatergreatergreater) && Right.is(tok::l_paren))
+    return false;
   if ((Right.is(TT_BinaryOperator) && !Left.is(tok::l_paren)) ||
       Left.isOneOf(TT_BinaryOperator, TT_ConditionalExpr))
     return true;
Index: unittests/Format/FormatTest.cpp
===================================================================
--- unittests/Format/FormatTest.cpp
+++ unittests/Format/FormatTest.cpp
@@ -9613,6 +9613,18 @@
   verifyFormat("A<A<int>>();", Spaces);
 }
 
+TEST_F(FormatTest, TrippleAngleBraces) {
+  verifyFormat("f<<<1, 1>>>();");
+  verifyFormat("f<<<1, 1, 1, s>>>();");
+  verifyFormat("f<<<a, b, c, d>>>();");
+  EXPECT_EQ("f<<<1, 1>>>();",
+            format("f <<< 1, 1 >>> ();"));
+  verifyFormat("f<param><<<1, 1>>>();");
+  verifyFormat("f<1><<<1, 1>>>();");
+  EXPECT_EQ("f<param><<<1, 1>>>();",
+            format("f< param > <<< 1, 1 >>> ();"));
+}
+
 TEST_F(FormatTest, HandleUnbalancedImplicitBracesAcrossPPBranches) {
   std::string code = "#if A\n"
                      "#if B\n"