From: Simon Pilgrim <llvm-dev@redking.me.uk>
Date: Tue, 17 Sep 2019 10:51:30 +0000 (+0000)
Subject: [X86] Use APInt::getLowBitsSet helper. NFCI.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e1592a6777e72574e35d71bb1ac56484738bda10;p=llvm

[X86] Use APInt::getLowBitsSet helper. NFCI.

Also avoids a static analyzer warning about out of range shifts.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@372103 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 58b1d47aa2c..b0c64a1bd8a 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -20301,7 +20301,8 @@ X86TargetLowering::BuildSDIVPow2(SDNode *N, const APInt &Divisor,
   SDLoc DL(N);
   SDValue N0 = N->getOperand(0);
   SDValue Zero = DAG.getConstant(0, DL, VT);
-  SDValue Pow2MinusOne = DAG.getConstant((1ULL << Lg2) - 1, DL, VT);
+  APInt Lg2Mask = APInt::getLowBitsSet(VT.getSizeInBits(), Lg2);
+  SDValue Pow2MinusOne = DAG.getConstant(Lg2Mask, DL, VT);
 
   // If N0 is negative, we need to add (Pow2 - 1) to it before shifting right.
   SDValue Cmp = DAG.getSetCC(DL, MVT::i8, N0, Zero, ISD::SETLT);