diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -7850,7 +7850,7 @@
   // return popcount(~x);
   //
   // Ref: "Hacker's Delight" by Henry Warren
-  for (unsigned i = 0; (1U << i) <= (NumBitsPerElt / 2); ++i) {
+  for (unsigned i = 0; (1U << i) < NumBitsPerElt; ++i) {
     SDValue Tmp = DAG.getConstant(1ULL << i, dl, ShVT);
     Op = DAG.getNode(ISD::OR, dl, VT, Op,
                      DAG.getNode(ISD::SRL, dl, VT, Op, Tmp));
diff --git a/llvm/test/CodeGen/RISCV/pr56457.ll b/llvm/test/CodeGen/RISCV/pr56457.ll
--- a/llvm/test/CodeGen/RISCV/pr56457.ll
+++ b/llvm/test/CodeGen/RISCV/pr56457.ll
@@ -18,6 +18,9 @@
 ; CHECK-NEXT:    slli a1, a0, 49
 ; CHECK-NEXT:    srli a1, a1, 53
 ; CHECK-NEXT:    or a0, a0, a1
+; CHECK-NEXT:    slli a1, a0, 49
+; CHECK-NEXT:    srli a1, a1, 57
+; CHECK-NEXT:    or a0, a0, a1
 ; CHECK-NEXT:    not a0, a0
 ; CHECK-NEXT:    slli a0, a0, 49
 ; CHECK-NEXT:    srli a0, a0, 49