Add sub/mul overflow intrinsics. This currently doesn't have a
target-independent way of determining overflow on multiplication. It's very
tricky. Patch by Zoltan Varga!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60800 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 979dea0..bb3b42c 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1511,6 +1511,10 @@
     return;
   case ISD::SADDO:
   case ISD::UADDO:
+  case ISD::SSUBO:
+  case ISD::USUBO:
+  case ISD::SMULO:
+  case ISD::UMULO:
     if (Op.getResNo() != 1)
       return;
     // The boolean result conforms to getBooleanContents.  Fall through.
@@ -1919,6 +1923,10 @@
 
   case ISD::SADDO:
   case ISD::UADDO:
+  case ISD::SSUBO:
+  case ISD::USUBO:
+  case ISD::SMULO:
+  case ISD::UMULO:
     if (Op.getResNo() != 1)
       break;
     // The boolean result conforms to getBooleanContents.  Fall through.
@@ -5216,6 +5224,10 @@
   case ISD::ADDE:        return "adde";
   case ISD::SADDO:       return "saddo";
   case ISD::UADDO:       return "uaddo";
+  case ISD::SSUBO:       return "ssubo";
+  case ISD::USUBO:       return "usubo";
+  case ISD::SMULO:       return "smulo";
+  case ISD::UMULO:       return "umulo";
   case ISD::SUBC:        return "subc";
   case ISD::SUBE:        return "sube";
   case ISD::SHL_PARTS:   return "shl_parts";