[llvm] r365016 - [X86] LowerFunnelShift - use modulo constant shift amount.

[Simon Pilgrim via llvm-commits]

Author: rksimon
Date: Wed Jul  3 03:04:16 2019
New Revision: 365016

URL: http://llvm.org/viewvc/llvm-project?rev=365016&view=rev
Log:
[X86] LowerFunnelShift - use modulo constant shift amount.

This avoids the use of getZExtValue and uses the modulo shift amount which is whats expected for funnel shifts anyhow. 

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=365016&r1=365015&r2=365016&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Wed Jul  3 03:04:16 2019
@@ -17831,7 +17831,7 @@ static SDValue LowerFunnelShift(SDValue
 
     APInt APIntShiftAmt;
     if (isConstantSplat(Amt, APIntShiftAmt)) {
-      uint64_t ShiftAmt = APIntShiftAmt.getZExtValue();
+      uint64_t ShiftAmt = APIntShiftAmt.urem(VT.getScalarSizeInBits());
       return DAG.getNode(IsFSHR ? X86ISD::VSHRD : X86ISD::VSHLD, DL, VT,
                          Op0, Op1, DAG.getConstant(ShiftAmt, DL, MVT::i8));
     }