Merging r309325:

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r309325 | ab | 2017-07-27 14:28:59 -0700 (Thu, 27 Jul 2017) | 8 lines

[X86] Don't lie about legality to TLI's demanded bits.

Like r309323, X86 had a typo where it passed the wrong flags to TLO.

Found by inspection; I haven't been able to tickle this into having
observable behavior.  I don't think it does, given that X86 doesn't have
custom demanded bits logic, and the generic logic doesn't have a lot of
exposure to illegal constructs.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_50@309587 91177308-0d34-0410-b5e6-96231b3b80d8

Author: zmodem

lib/Target/X86/X86ISelLowering.cpp

@@ -30612,8 +30612,8 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
     assert(BitWidth >= 8 && BitWidth <= 64 && "Invalid mask size");
     APInt DemandedMask(APInt::getSignMask(BitWidth));
     KnownBits Known;
-    TargetLowering::TargetLoweringOpt TLO(DAG, DCI.isBeforeLegalize(),
-                                          DCI.isBeforeLegalizeOps());
+    TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
+                                          !DCI.isBeforeLegalizeOps());
     if (TLI.ShrinkDemandedConstant(Cond, DemandedMask, TLO) ||
         TLI.SimplifyDemandedBits(Cond, DemandedMask, Known, TLO)) {
       // If we changed the computation somewhere in the DAG, this change will