Static assert the size of offset type in row table at where assumes it

Author: zanmato1984

cpp/src/arrow/acero/swiss_join_avx2.cc

@@ -49,6 +49,9 @@ int RowArrayAccessor::Visit_avx2(const RowTableImpl& rows, int column_id, int nu
     int varbinary_column_id = VarbinaryColumnId(rows.metadata(), column_id);
     const uint8_t* row_ptr_base = rows.data(2);
     const RowTableImpl::offset_type* row_offsets = rows.offsets();
+    static_assert(
+        sizeof(RowTableImpl::offset_type) == sizeof(int64_t),
+        "RowArrayAccessor::Visit_avx2 only supports 64-bit RowTableImpl::offset_type");
 
     if (varbinary_column_id == 0) {
       // Case 1: This is the first varbinary column

cpp/src/arrow/compute/row/compare_internal_avx2.cc

@@ -251,6 +251,9 @@ uint32_t KeyCompare::CompareBinaryColumnToRowHelper_avx2(
             _mm256_loadu_si256(reinterpret_cast<const __m256i*>(left_to_right_map) + i);
       }
 
+      static_assert(sizeof(RowTableImpl::offset_type) == sizeof(int64_t),
+                    "KeyCompare::CompareBinaryColumnToRowHelper_avx2 only supports "
+                    "64-bit RowTableImpl::offset_type");
       auto offsets_right_i64 =
           reinterpret_cast<const arrow::util::int64_for_gather_t*>(offsets_right);
       // Gather the lower/higher 4 64-bit row offsets based on the lower/higher 4 32-bit
@@ -415,6 +418,9 @@ inline uint64_t Compare8_Binary_avx2(uint32_t length, const uint8_t* left_base,
   if (use_selection) {
     _mm256_storeu_si256(reinterpret_cast<__m256i*>(irow_left_array), irow_left);
   }
+  static_assert(
+      sizeof(RowTableImpl::offset_type) * 4 == sizeof(__m256i),
+      "Unexpected RowTableImpl::offset_type size in KeyCompare::Compare8_Binary_avx2");
   _mm256_storeu_si256(reinterpret_cast<__m256i*>(offset_right_array), offset_right_lo);
   _mm256_storeu_si256(reinterpret_cast<__m256i*>(&offset_right_array[4]),
                       offset_right_hi);