diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index b462a4d..3eb74ca 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -64,6 +64,7 @@
 //   , => _COMMA
 //   = => _EQ
 //   C++ => CXX
+//   . => _
 
 // Developer Driver Options
 
@@ -420,6 +421,8 @@
 def mno_sse3 : Flag<"-mno-sse3">, Group<m_x86_Features_Group>;
 def mno_sse4a : Flag<"-mno-sse4a">, Group<m_x86_Features_Group>;
 def mno_sse4 : Flag<"-mno-sse4">, Group<m_x86_Features_Group>;
+def mno_sse4_1 : Flag<"-mno-sse4.1">, Group<m_x86_Features_Group>;
+def mno_sse4_2 : Flag<"-mno-sse4.2">, Group<m_x86_Features_Group>;
 def mno_sse : Flag<"-mno-sse">, Group<m_x86_Features_Group>;
 def mno_ssse3 : Flag<"-mno-ssse3">, Group<m_x86_Features_Group>;
 
@@ -434,6 +437,8 @@
 def msse3 : Flag<"-msse3">, Group<m_x86_Features_Group>;
 def msse4a : Flag<"-msse4a">, Group<m_x86_Features_Group>;
 def msse4 : Flag<"-msse4">, Group<m_x86_Features_Group>;
+def msse4_1 : Flag<"-msse4.1">, Group<m_x86_Features_Group>;
+def msse4_2 : Flag<"-msse4.2">, Group<m_x86_Features_Group>;
 def msse : Flag<"-msse">, Group<m_x86_Features_Group>;
 def mssse3 : Flag<"-mssse3">, Group<m_x86_Features_Group>;
 def mthumb : Flag<"-mthumb">, Group<m_Group>;
diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index 96ae4b7..608a4f0 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -734,8 +734,10 @@
 bool X86TargetInfo::setFeatureEnabled(llvm::StringMap<bool> &Features,
                                       const std::string &Name,
                                       bool Enabled) const {
-  // FIXME: This *really* should not be here.
-  if (!Features.count(Name) && Name != "sse4")
+  // FIXME: This *really* should not be here.  We need some way of translating
+  // options into llvm subtarget features.
+  if (!Features.count(Name) &&
+      (Name != "sse4" && Name != "sse4.2" && Name != "sse4.1"))
     return false;
 
   if (Enabled) {
@@ -751,9 +753,12 @@
     else if (Name == "ssse3")
       Features["mmx"] = Features["sse"] = Features["sse2"] = Features["sse3"] =
         Features["ssse3"] = true;
-    else if (Name == "sse4")
+    else if (Name == "sse4" || Name == "sse4.2")
       Features["mmx"] = Features["sse"] = Features["sse2"] = Features["sse3"] =
         Features["ssse3"] = Features["sse41"] = Features["sse42"] = true;
+    else if (Name == "sse4.1")
+      Features["mmx"] = Features["sse"] = Features["sse2"] = Features["sse3"] =
+        Features["ssse3"] = Features["sse41"] = true;
     else if (Name == "3dnow")
       Features["3dnowa"] = true;
     else if (Name == "3dnowa")