Index: include/clang/Tooling/Inclusions/HeaderIncludes.h
===================================================================
--- include/clang/Tooling/Inclusions/HeaderIncludes.h
+++ include/clang/Tooling/Inclusions/HeaderIncludes.h
@@ -32,7 +32,7 @@
   /// 0. Otherwise, returns the priority of the matching category or INT_MAX.
   /// NOTE: this API is not thread-safe!
   int getIncludePriority(StringRef IncludeName, bool CheckMainHeader) const;
-
+  int getSortIncludePriority(StringRef IncludeName) const;
 private:
   bool isMainHeader(StringRef IncludeName) const;
 
Index: include/clang/Tooling/Inclusions/IncludeStyle.h
===================================================================
--- include/clang/Tooling/Inclusions/IncludeStyle.h
+++ include/clang/Tooling/Inclusions/IncludeStyle.h
@@ -58,6 +58,8 @@
     std::string Regex;
     /// The priority to assign to this category.
     int Priority;
+    /// The custom priority to sort before grouping.
+    int SortPriority;
     bool operator==(const IncludeCategory &Other) const {
       return Regex == Other.Regex && Priority == Other.Priority;
     }
Index: lib/Format/Format.cpp
===================================================================
--- lib/Format/Format.cpp
+++ lib/Format/Format.cpp
@@ -1023,6 +1023,39 @@
   return Style;
 }
 
+FormatStyle getNetBSDStyle() {
+  FormatStyle NetBSDStyle = getLLVMStyle();
+  NetBSDStyle.AlignTrailingComments = true;
+  NetBSDStyle.AlwaysBreakAfterReturnType = FormatStyle::RTBS_AllDefinitions;
+  NetBSDStyle.AlignConsecutiveMacros = true;
+  NetBSDStyle.BreakBeforeBraces = FormatStyle::BS_Mozilla;
+  NetBSDStyle.ColumnLimit = 80;
+  NetBSDStyle.ContinuationIndentWidth = 4;
+  NetBSDStyle.Cpp11BracedListStyle = false;
+  NetBSDStyle.FixNamespaceComments = true;
+  NetBSDStyle.IndentCaseLabels = false;
+  NetBSDStyle.IndentWidth = 8;
+  NetBSDStyle.IncludeStyle.IncludeBlocks = tooling::IncludeStyle::IBS_Regroup;
+  NetBSDStyle.IncludeStyle.IncludeCategories = {
+      {"^<sys/param\.h>", 1, 0},
+      {"^<sys/types\.h>", 1, 1},
+      {"^<sys.*/", 1, 2},
+      {"^<uvm/", 2, 3},
+      {"^<machine/", 3, 4},
+      {"^<dev/", 4, 5},
+      {"^<net.*/", 5, 6},
+      {"^<protocols/", 5, 7},
+      {"^<(fs|miscfs|msdosfs|nfs|ntfs|ufs)/", 6, 8},
+      {"^<(x86|amd64|i386|xen)/", 7, 8},
+      {"<path", 8, 10},
+      {"^\<[^/].*\.h>", 9, 11},
+      {"^\"\w.*\.h\"$", 10, 12}};
+  NetBSDStyle.SortIncludes = true;
+  NetBSDStyle.TabWidth = 8;
+  NetBSDStyle.UseTab = FormatStyle::UT_Always;
+  return NetBSDStyle;
+}
+
 FormatStyle getNoStyle() {
   FormatStyle NoStyle = getLLVMStyle();
   NoStyle.DisableFormat = true;
@@ -1047,6 +1080,8 @@
     *Style = getGNUStyle();
   } else if (Name.equals_lower("microsoft")) {
     *Style = getMicrosoftStyle(Language);
+  } else if (Name.equals_lower("netbsd")) {
+    *Style = getNetBSDStyle();
   } else if (Name.equals_lower("none")) {
     *Style = getNoStyle();
   } else {
@@ -1774,8 +1809,9 @@
 static void sortCppIncludes(const FormatStyle &Style,
                             const SmallVectorImpl<IncludeDirective> &Includes,
                             ArrayRef<tooling::Range> Ranges, StringRef FileName,
-                            StringRef Code,
-                            tooling::Replacements &Replaces, unsigned *Cursor) {
+                            StringRef Code, tooling::Replacements &Replaces,
+                            unsigned *Cursor) {
+  tooling::IncludeCategoryManager Categories(Style.IncludeStyle, FileName);
   unsigned IncludesBeginOffset = Includes.front().Offset;
   unsigned IncludesEndOffset =
       Includes.back().Offset + Includes.back().Text.size();
@@ -1783,11 +1819,15 @@
   if (!affectsRange(Ranges, IncludesBeginOffset, IncludesEndOffset))
     return;
   SmallVector<unsigned, 16> Indices;
-  for (unsigned i = 0, e = Includes.size(); i != e; ++i)
+  SmallVector<unsigned, 16> IncludesPriority;
+  for (unsigned i = 0, e = Includes.size(); i != e; ++i) {
+    IncludesPriority.push_back(
+        Categories.getSortIncludePriority(Includes[i].Filename));
     Indices.push_back(i);
+  }
   llvm::stable_sort(Indices, [&](unsigned LHSI, unsigned RHSI) {
-    return std::tie(Includes[LHSI].Category, Includes[LHSI].Filename) <
-           std::tie(Includes[RHSI].Category, Includes[RHSI].Filename);
+    return std::tie(IncludesPriority[LHSI], Includes[LHSI].Filename) <
+           std::tie(IncludesPriority[RHSI], Includes[RHSI].Filename);
   });
   // The index of the include on which the cursor will be put after
   // sorting/deduplicating.
Index: lib/Tooling/Inclusions/HeaderIncludes.cpp
===================================================================
--- lib/Tooling/Inclusions/HeaderIncludes.cpp
+++ lib/Tooling/Inclusions/HeaderIncludes.cpp
@@ -199,6 +199,15 @@
   return Ret;
 }
 
+int IncludeCategoryManager::getSortIncludePriority(StringRef IncludeName) const {
+  int Ret = INT_MAX;
+  for (unsigned i = 0, e = CategoryRegexs.size(); i != e; ++i)
+    if (CategoryRegexs[i].match(IncludeName)) {
+      Ret = Style.IncludeCategories[i].SortPriority;
+      break;
+    }
+  return Ret;
+}
 bool IncludeCategoryManager::isMainHeader(StringRef IncludeName) const {
   if (!IncludeName.startswith("\""))
     return false;
Index: lib/Tooling/Inclusions/IncludeStyle.cpp
===================================================================
--- lib/Tooling/Inclusions/IncludeStyle.cpp
+++ lib/Tooling/Inclusions/IncludeStyle.cpp
@@ -17,6 +17,7 @@
     IO &IO, IncludeStyle::IncludeCategory &Category) {
   IO.mapOptional("Regex", Category.Regex);
   IO.mapOptional("Priority", Category.Priority);
+  IO.mapOptional("SortPriority", Category.SortPriority);
 }
 
 void ScalarEnumerationTraits<IncludeStyle::IncludeBlocksStyle>::enumeration(