refine docs

Author: shiltian

clang/include/clang/Basic/AttrDocs.td

@@ -7548,11 +7548,12 @@ A managed variable can be accessed in both device and host code.
 def CUDAClusterDimsAttrDoc : Documentation {
   let Category = DocCatDecl;
   let Content = [{
-In CUDA/HIP programming, the ``__cluster_dims__`` attribute can be applied to a kernel function
-to set the dimensions of a thread block cluster, which is an optional level of hierarchy and made
-up of thread blocks. ``__cluster_dims__`` defines the cluster size as ``(X, Y, Z)``, where each value
-is the number of thread blocks in that dimension. The ``__cluster_dims__`` and `__no_cluster__``
-attributes are mutually exclusive.
+In CUDA/HIP programming, the ``cluster_dims`` attribute, conventionally exposed as
+``__cluster_dims__`` macro, can be applied to a kernel function to set the dimensions of a
+thread block cluster, which is an optional level of hierarchy and made up of thread blocks.
+``__cluster_dims__`` defines the cluster size as ``(X, Y, Z)``, where each value is the number
+of thread blocks in that dimension. The ``__cluster_dims__`` and `__no_cluster__`` attributes
+are mutually exclusive.
 
 .. code::
 
@@ -7568,12 +7569,12 @@ def CUDANoClusterAttrDoc : Documentation {
   let Content = [{
 In CUDA/HIP programming, a kernel function can still be launched with the cluster feature
 enabled at runtime, even without the ``__cluster_dims__`` attribute. The LLVM/Clang-exclusive
-``__no_cluster__`` attribute can be applied to a kernel function to explicitly indicate that
-the cluster feature will not be enabled either at compile time or at kernel launch time. This
-allows the compiler to apply certain optimizations without assuming that clustering could be
-enabled at runtime. It is undefined behavior to launch a kernel with the ``__no_cluster__``
-attribute if the cluster feature is enabled at runtime. The ``__cluster_dims__`` and
-``__no_cluster__`` attributes are mutually exclusive.
+``no_cluster`` attribute, conventionally exposed as ``__no_cluster__`` macro, can be applied
+to a kernel function to explicitly indicate that the cluster feature will not be enabled either
+at compile time or at kernel launch time. This allows the compiler to apply certain optimizations
+without assuming that clustering could be enabled at runtime. It is undefined behavior to launch
+a kernel with the ``__no_cluster__`` attribute if the cluster feature is enabled at runtime.
+The ``__cluster_dims__`` and ``__no_cluster__`` attributes are mutually exclusive.
 
 .. code::