diff --git a/velox/common/base/SimdUtil.cpp b/velox/common/base/SimdUtil.cpp
index 0aaf5398591e..080081804b7b 100644
--- a/velox/common/base/SimdUtil.cpp
+++ b/velox/common/base/SimdUtil.cpp
@@ -23,6 +23,7 @@ void gatherBits(
     const uint64_t* bits,
     folly::Range<const int32_t*> indexRange,
     uint64_t* result) {
+  constexpr int32_t kStep = xsimd::batch<int32_t>::size;
   auto size = indexRange.size();
   auto indices = indexRange.data();
   uint8_t* resultPtr = reinterpret_cast<uint8_t*>(result);
@@ -35,38 +36,17 @@ void gatherBits(
     *resultPtr = smallResult;
     return;
   }
-  constexpr int32_t kStep = xsimd::batch<int32_t>::size;
   int32_t i = 0;
   for (; i + kStep < size; i += kStep) {
-    if constexpr (kStep == 8) {
-      *(resultPtr++) =
-          simd::gather8Bits(bits, xsimd::load_unaligned(indices + i), 8);
-    } else {
-      VELOX_DCHECK_EQ(kStep, 4);
       uint16_t flags =
           simd::gather8Bits(bits, xsimd::load_unaligned(indices + i), kStep);
-      if (i % 8 == 0) {
-        resultPtr[i / 8] = flags;
-      } else {
-        resultPtr[i / 8] |= flags << 4;
-      }
-    }
+      bits::storeBitsToByte<kStep>(flags, resultPtr, i);
   }
   auto bitsLeft = size - i;
   if (bitsLeft > 0) {
-    if constexpr (kStep == 8) {
-      *resultPtr =
-          simd::gather8Bits(bits, xsimd::load_unaligned(indices + i), bitsLeft);
-    } else {
-      VELOX_DCHECK_EQ(kStep, 4);
       uint16_t flags =
           simd::gather8Bits(bits, xsimd::load_unaligned(indices + i), bitsLeft);
-      if (i % 8 == 0) {
-        resultPtr[i / 8] = flags;
-      } else {
-        resultPtr[i / 8] |= flags << 4;
-      }
-    }
+      bits::storeBitsToByte<kStep>(flags, resultPtr, i);
   }
 }