[llvm-commits] CVS: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

[Chris Lattner]

Changes in directory llvm/lib/CodeGen/SelectionDAG:

SelectionDAG.cpp updated: 1.304 -> 1.305
---
Log message:

Fold shifts with undef operands.


---
Diffs of the changes:  (+7 -0)

 SelectionDAG.cpp |    7 +++++++
 1 files changed, 7 insertions(+)


Index: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1.304 llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1.305
--- llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1.304	Sat May  6 18:05:41 2006
+++ llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp	Mon May  8 12:29:49 2006
@@ -1439,11 +1439,14 @@
       case ISD::FSUB:
       case ISD::FDIV:
       case ISD::FREM:
+      case ISD::SRA:
         return N1;     // fold op(undef, arg2) -> undef
       case ISD::UDIV:
       case ISD::SDIV:
       case ISD::UREM:
       case ISD::SREM:
+      case ISD::SRL:
+      case ISD::SHL:
         return getConstant(0, VT);    // fold op(undef, arg2) -> 0
       }
     }
@@ -1467,9 +1470,13 @@
       return N2;       // fold op(arg1, undef) -> undef
     case ISD::MUL: 
     case ISD::AND:
+    case ISD::SRL:
+    case ISD::SHL:
       return getConstant(0, VT);  // fold op(arg1, undef) -> 0
     case ISD::OR:
       return getConstant(MVT::getIntVTBitMask(VT), VT);
+    case ISD::SRA:
+      return N1;
     }
   }