[SYCL] This PR adds the minimum modifications to the Eigen unsupported module required to run it on devices supporting SYCL.

* Abstracting the pointer type so that both SYCL memory and pointer can be captured.
* Converting SYCL virtual pointer to SYCL device memory in Eigen evaluator class.
* Binding SYCL placeholder accessor to command group handler by using bind method in Eigen evaluator node.
* Adding SYCL macro for controlling loop unrolling.
* Modifying the TensorDeviceSycl.h and SYCL executor method to adopt the above changes.

1 files changed, 6 insertions, 2 deletions

diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceDefault.h b/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceDefault.h
index 8cb95f731..46b9d3ab2 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceDefault.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorDeviceDefault.h
@@ -39,6 +39,10 @@ struct DefaultDevice {
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE void memset(void* buffer, int c, size_t n) const {
     ::memset(buffer, c, n);
   }
+  template<typename Type>
+  EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE Type get(Type data) const { 
+    return data;
+  }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t numThreads() const {
 #if !defined(EIGEN_GPU_COMPILE_PHASE)
@@ -54,7 +58,7 @@ struct DefaultDevice {
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t firstLevelCacheSize() const {
-#if !defined(EIGEN_GPU_COMPILE_PHASE) && !defined(__SYCL_DEVICE_ONLY__)
+#if !defined(EIGEN_GPU_COMPILE_PHASE) && !defined(SYCL_DEVICE_ONLY)
     // Running on the host CPU
     return l1CacheSize();
 #elif defined(EIGEN_HIP_DEVICE_COMPILE)
@@ -67,7 +71,7 @@ struct DefaultDevice {
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t lastLevelCacheSize() const {
-#if !defined(EIGEN_GPU_COMPILE_PHASE) && !defined(__SYCL_DEVICE_ONLY__)
+#if !defined(EIGEN_GPU_COMPILE_PHASE) && !defined(SYCL_DEVICE_ONLY)
     // Running single threaded on the host CPU
     return l3CacheSize();
 #elif defined(EIGEN_HIP_DEVICE_COMPILE)