[ROCm] fixes ambiguous calls to shfl* where there is no explicit type conversion from c10::Half to __half (#360)

[ROCm] fixes ambiguous calls to `shfl*` where there is no explicit type
conversion from `c10::Half` to `__half`

Author: ashwinma

csrc/cuda/utils.cuh

@@ -6,9 +6,10 @@
   AT_ASSERTM(x.device().is_cuda(), #x " must be CUDA tensor")
 #define CHECK_INPUT(x) AT_ASSERTM(x, "Input mismatch")
 
-__device__ __inline__ at::Half
-__shfl_sync(const unsigned mask, const at::Half var, const int srcLane) {
-  return __shfl_sync(mask, var.operator __half(), srcLane);
+__device__ __inline__ at::Half __shfl_up_sync(const unsigned mask,
+                                              const at::Half var,
+                                              const unsigned int delta) {
+  return __shfl_up_sync(mask, var.operator __half(), delta);
 }
 
 __device__ __inline__ at::Half __shfl_down_sync(const unsigned mask,
@@ -17,6 +18,27 @@ __device__ __inline__ at::Half __shfl_down_sync(const unsigned mask,
   return __shfl_down_sync(mask, var.operator __half(), delta);
 }
 
+__device__ __inline__ at::Half __shfl_sync(const unsigned mask,
+                                           const at::Half var,
+                                           const int delta) {
+  return __shfl_sync(mask, var.operator __half(), delta);
+}
+
+__device__ __inline__ at::Half __shfl_up(const at::Half var,
+                                         const unsigned int delta) {
+  return __shfl_up(var.operator __half(), delta);
+}
+
+__device__ __inline__ at::Half __shfl_down(const at::Half var,
+                                           const unsigned int delta) {
+  return __shfl_down(var.operator __half(), delta);
+}
+
+__device__ __inline__ at::Half
+__shfl(const at::Half var, const int delta) {
+  return __shfl(var.operator __half(), delta);
+}
+
 #ifdef USE_ROCM
 __device__ __inline__ at::Half __ldg(const at::Half* ptr) {
   return __ldg(reinterpret_cast<const __half*>(ptr));