[llvm] [ValueTracking][SelectionDAG] Use KnownBits::reverseBits/byteSwap. NFC (PR #155847)

[Craig Topper via llvm-commits]

https://github.com/topperc created https://github.com/llvm/llvm-project/pull/155847

None

>From d462f874c2a2e5b535cfb963e696189e0a592712 Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper at sifive.com>
Date: Thu, 28 Aug 2025 07:55:42 -0700
Subject: [PATCH] [ValueTracking][SelectionDAG] Use
 KnownBits::reverseBits/byteSwap. NFC

---
 llvm/lib/Analysis/ValueTracking.cpp              | 6 ++----
 llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp | 6 ++----
 2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 7fe129b8456f6..e6282fc8cdbbc 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -1834,13 +1834,11 @@ static void computeKnownBitsFromOperator(const Operator *I,
       }
       case Intrinsic::bitreverse:
         computeKnownBits(I->getOperand(0), DemandedElts, Known2, Q, Depth + 1);
-        Known.Zero |= Known2.Zero.reverseBits();
-        Known.One |= Known2.One.reverseBits();
+        Known = Known.unionWith(Known2.reverseBits());
         break;
       case Intrinsic::bswap:
         computeKnownBits(I->getOperand(0), DemandedElts, Known2, Q, Depth + 1);
-        Known.Zero |= Known2.Zero.byteSwap();
-        Known.One |= Known2.One.byteSwap();
+        Known = Known.unionWith(Known2.byteSwap());
         break;
       case Intrinsic::ctlz: {
         computeKnownBits(I->getOperand(0), DemandedElts, Known2, Q, Depth + 1);
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 402a012e8e555..7e5844d1a8963 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -2363,8 +2363,7 @@ bool TargetLowering::SimplifyDemandedBits(
     if (SimplifyDemandedBits(Src, DemandedSrcBits, DemandedElts, Known2, TLO,
                              Depth + 1))
       return true;
-    Known.One = Known2.One.reverseBits();
-    Known.Zero = Known2.Zero.reverseBits();
+    Known = Known2.reverseBits();
     break;
   }
   case ISD::BSWAP: {
@@ -2397,8 +2396,7 @@ bool TargetLowering::SimplifyDemandedBits(
     if (SimplifyDemandedBits(Src, DemandedSrcBits, DemandedElts, Known2, TLO,
                              Depth + 1))
       return true;
-    Known.One = Known2.One.byteSwap();
-    Known.Zero = Known2.Zero.byteSwap();
+    Known = Known2.byteSwap();
     break;
   }
   case ISD::CTPOP: {