Adding Dim3 class

This adds a dim3 class for gpu code and a convenience class decorator for lang.CppClass

src/pystencilssfg/extensions/gpu.py

+from pystencilssfg import lang
+
+
+def dim3class(gpu_runtime_header: str, *, cls_name: str = "dim3"):
+    """
+    >>> dim3 = dim3class("<hip/hip_runtime.h>")
+    >>> dim3.ctor(64, 1, 1)
+    'dim3{64, 1, 1}'
+    Args:
+        gpu_runtime_header: String with the name of the gpu runtime header
+        cls_name: String with the acutal name (default "dim3")
+    Returns:
+        Dim3Class: A `lang.CppClass` that mimics cuda's/hip's `dim3`
+    """
+    @lang.cppclass(cls_name, gpu_runtime_header)
+    class Dim3Class:
+        def ctor(self, dim0=1, dim1=1, dim2=1):
+            return self.ctor_bind(dim0, dim1, dim2)
+
+        @property
+        def x(self):
+            return lang.AugExpr.format("{}.x", self)
+
+        @property
+        def y(self):
+            return lang.AugExpr.format("{}.y", self)
+
+        @property
+        def z(self):
+            return lang.AugExpr.format("{}.z", self)
+
+        @property
+        def dims(self):
+            """The dims property."""
+            return [self.x, self.y, self.z]
+
+    return Dim3Class