From: Eli Friedman <eli.friedman@gmail.com>
Date: Thu, 13 Oct 2011 22:40:23 +0000 (+0000)
Subject: Simplify and avoid undefined shift.  Based on patch by Ahmed Charles.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=8e4d0429de3d44a4c5b02b3d27cb0b78520609ba;p=oota-llvm.git

Simplify and avoid undefined shift.  Based on patch by Ahmed Charles.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141903 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 0313f99908c..2ac52cfc366 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -3944,8 +3944,7 @@ SDValue ARMTargetLowering::LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG,
       }
 
       // Try an immediate VMVN.
-      uint64_t NegatedImm = (SplatBits.getZExtValue() ^
-                             ((1LL << SplatBitSize) - 1));
+      uint64_t NegatedImm = (~SplatBits).getZExtValue();
       Val = isNEONModifiedImm(NegatedImm,
                                       SplatUndef.getZExtValue(), SplatBitSize,
                                       DAG, VmovVT, VT.is128BitVector(),