Index: lib/CodeGen/RegUsageInfoCollector.cpp
===================================================================
--- lib/CodeGen/RegUsageInfoCollector.cpp
+++ lib/CodeGen/RegUsageInfoCollector.cpp
@@ -171,28 +171,27 @@
   }
 
   // Insert any register fully saved via subregisters.
-  for (unsigned PReg = 1, PRegE = TRI->getNumRegs(); PReg < PRegE; ++PReg) {
-    if (SavedRegs.test(PReg))
+  for (const TargetRegisterClass *RC : TRI->regclasses()) {
+    if (!RC->CoveredBySubRegs)
       continue;
 
-    // Check if PReg is fully covered by its subregs.
-    bool CoveredBySubRegs = false;
-    for (const TargetRegisterClass *RC : TRI->regclasses())
-      if (RC->CoveredBySubRegs && RC->contains(PReg)) {
-        CoveredBySubRegs = true;
-        break;
-      }
-    if (!CoveredBySubRegs)
-      continue;
-
-    // Add PReg to SavedRegs if all subregs are saved.
-    bool AllSubRegsSaved = true;
-    for (MCSubRegIterator SR(PReg, TRI, false); SR.isValid(); ++SR)
-      if (!SavedRegs.test(*SR)) {
-        AllSubRegsSaved = false;
-        break;
-      }
-    if (AllSubRegsSaved)
-      SavedRegs.set(PReg);
+    for (unsigned PReg = 1, PRegE = TRI->getNumRegs(); PReg < PRegE; ++PReg) {
+      if (SavedRegs.test(PReg))
+        continue;
+
+      // Check if PReg is fully covered by its subregs.
+      if (!RC->contains(PReg))
+        continue;
+
+      // Add PReg to SavedRegs if all subregs are saved.
+      bool AllSubRegsSaved = true;
+      for (MCSubRegIterator SR(PReg, TRI, false); SR.isValid(); ++SR)
+        if (!SavedRegs.test(*SR)) {
+          AllSubRegsSaved = false;
+          break;
+        }
+      if (AllSubRegsSaved)
+        SavedRegs.set(PReg);
+    }
   }
 }