[Bugfix] Fallback to the old AtomicAdd implementation for legacy architectures (#1306)

src/tl_templates/cuda/atomic.h

@@ -169,6 +169,7 @@ TL_DEVICE T1 AtomicMinRet(T1 &ref, T2 val,
   }
 }
 
+#if (defined(__CUDA_ARCH_LIST__) && (__CUDA_ARCH_LIST__ > 890))
 template <typename T1, typename T2>
 TL_DEVICE void AtomicAdd(T1 &ref, T2 val,
                          int memory_order = int(cuda::memory_order_relaxed)) {
@@ -236,14 +237,18 @@ TL_DEVICE void AtomicAdd(T1 &ref, T2 val,
       }
     }
   } else {
-#if CUDART_VERSION >= 11080
-    cuda::atomic_ref<NT1, cuda::thread_scope_device> aref(*address);
-    aref.fetch_add(cuda_cast<NT1>(val), cuda::memory_order(memory_order));
-#else
-    TL_NOT_IMPLEMENTED();
-#endif
+    atomicAdd(reinterpret_cast<NT1 *>(address), cuda_cast<NT1>(val));
   }
 }
+#else
+template <typename T1, typename T2>
+TL_DEVICE void AtomicAdd(T1 &ref, T2 val,
+                         int memory_order = int(cuda::memory_order_relaxed)) {
+  using NT1 = typename normalize_atomic_type<T1>::type;
+  (void)memory_order;
+  atomicAdd(reinterpret_cast<NT1 *>(&ref), cuda_cast<NT1>(val));
+}
+#endif
 
 template <typename T1, typename T2>
 TL_DEVICE T1 AtomicAddRet(T1 &ref, T2 val,
@@ -643,6 +648,48 @@ AtomicAddx4Ret(float *ref, float *val,
     return ret_val;
   }
 }
+#else
+TL_DEVICE void AtomicAddx2(float *ref, float *val,
+                           int memory_order = int(cuda::memory_order_relaxed)) {
+  (void)memory_order;
+  float2 add_val = *reinterpret_cast<float2 *>(val);
+  atomicAdd(ref + 0, add_val.x);
+  atomicAdd(ref + 1, add_val.y);
+}
+
+TL_DEVICE float2
+AtomicAddx2Ret(float *ref, float *val,
+               int memory_order = int(cuda::memory_order_relaxed)) {
+  (void)memory_order;
+  float2 add_val = *reinterpret_cast<float2 *>(val);
+  float2 ret;
+  ret.x = atomicAdd(ref + 0, add_val.x);
+  ret.y = atomicAdd(ref + 1, add_val.y);
+  return ret;
+}
+
+TL_DEVICE void AtomicAddx4(float *ref, float *val,
+                           int memory_order = int(cuda::memory_order_relaxed)) {
+  (void)memory_order;
+  float4 add_val = *reinterpret_cast<float4 *>(val);
+  atomicAdd(ref + 0, add_val.x);
+  atomicAdd(ref + 1, add_val.y);
+  atomicAdd(ref + 2, add_val.z);
+  atomicAdd(ref + 3, add_val.w);
+}
+
+TL_DEVICE float4
+AtomicAddx4Ret(float *ref, float *val,
+               int memory_order = int(cuda::memory_order_relaxed)) {
+  (void)memory_order;
+  float4 add_val = *reinterpret_cast<float4 *>(val);
+  float4 ret;
+  ret.x = atomicAdd(ref + 0, add_val.x);
+  ret.y = atomicAdd(ref + 1, add_val.y);
+  ret.z = atomicAdd(ref + 2, add_val.z);
+  ret.w = atomicAdd(ref + 3, add_val.w);
+  return ret;
+}
 #endif
 
 template <typename T> TL_DEVICE T AtomicLoad(T &ref, int memory_order) {