ARROW-17412: [C++] AsofJoin multiple keys and types

cpp/src/arrow/array/data.h

@@ -167,6 +167,11 @@ struct ARROW_EXPORT ArrayData {
 
   std::shared_ptr<ArrayData> Copy() const { return std::make_shared<ArrayData>(*this); }
 
+  bool IsNull(int64_t i) const {
+    return ((buffers[0] != NULLPTR) ? !bit_util::GetBit(buffers[0]->data(), i + offset)
+                                    : null_count.load() == length);
+  }
+
   // Access a buffer's data as a typed C pointer
   template <typename T>
   inline const T* GetValues(int i, int64_t absolute_offset) const {
@@ -324,18 +329,14 @@ struct ARROW_EXPORT ArraySpan {
     return GetValues<T>(i, this->offset);
   }
 
-  bool IsNull(int64_t i) const {
-    return ((this->buffers[0].data != NULLPTR)
-                ? !bit_util::GetBit(this->buffers[0].data, i + this->offset)
-                : this->null_count == this->length);
-  }
-
-  bool IsValid(int64_t i) const {
+  inline bool IsValid(int64_t i) const {
     return ((this->buffers[0].data != NULLPTR)
                 ? bit_util::GetBit(this->buffers[0].data, i + this->offset)
                 : this->null_count != this->length);
   }
 
+  inline bool IsNull(int64_t i) const { return !IsValid(i); }
+
   std::shared_ptr<ArrayData> ToArrayData() const;
 
   std::shared_ptr<Array> ToArray() const;

cpp/src/arrow/compute/exec/asof_join_benchmark.cc

@@ -109,7 +109,7 @@ static void TableJoinOverhead(benchmark::State& state,
 
 static void AsOfJoinOverhead(benchmark::State& state) {
   int64_t tolerance = 0;
-  AsofJoinNodeOptions options = AsofJoinNodeOptions(kTimeCol, kKeyCol, tolerance);
+  AsofJoinNodeOptions options = AsofJoinNodeOptions(kTimeCol, {kKeyCol}, tolerance);
   TableJoinOverhead(
       state,
       TableGenerationProperties{int(state.range(0)), int(state.range(1)),