Refactor a bunch of includes so that TargetMachine.h doesn't have to include

[oota-llvm.git] / lib / CodeGen / SelectionDAG / TargetLowering.cpp

diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 41405408de53144e23e8af4e9a6588f01d9ba021..50d2dfb16e4ddbc55580d9df78ba839e43a1d6fe 100644 (file)
--- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetData.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/MRegisterInfo.h"
 #include "llvm/DerivedTypes.h"
@@ -467,8 +468,14 @@ bool TargetLowering::SimplifyDemandedBits(SDOperand Op, uint64_t DemandedMask,
       HighBits <<= MVT::getSizeInBits(VT) - ShAmt;
       uint64_t TypeMask = MVT::getIntVTBitMask(VT);
       
-      if (SimplifyDemandedBits(Op.getOperand(0),
-                               (DemandedMask << ShAmt) & TypeMask,
+      uint64_t InDemandedMask = (DemandedMask << ShAmt) & TypeMask;
+
+      // If any of the demanded bits are produced by the sign extension, we also
+      // demand the input sign bit.
+      if (HighBits & DemandedMask)
+        InDemandedMask |= MVT::getIntVTSignBit(VT);
+      
+      if (SimplifyDemandedBits(Op.getOperand(0), InDemandedMask,
                                KnownZero, KnownOne, TLO, Depth+1))
         return true;
       assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");