[Refactor] Simplify buffer_region_to_tile_region function in copy.py (#470)

* Removed redundant logic for handling region extents in the buffer_region_to_tile_region function, streamlining the code for better readability and maintainability.
* Enhanced error handling by focusing on essential checks while eliminating unnecessary complexity related to variable extents.

tilelang/language/copy.py

@@ -74,38 +74,9 @@ def buffer_region_to_tile_region(buffer_region: tir.BufferRegion, access_type: s
     mins = [x.min for x in buffer_region.region]
     region_extents = [x.extent for x in buffer_region.region]
     assert len(region_extents) >= len(
-        extents), f"region_extents = {region_extents}, extents = {extents}"
-
-    # If region_extents already contains all elements
-    # of extents (in any order), pass directly
-    tmp_extents = list(extents)
-    variable_extent_count = 0
-    for i in range(len(region_extents)):
-        v = region_extents[i]
-        if not isinstance(v, tir.IntImm):
-            variable_extent_count += 1
-            continue
-
-        if v in tmp_extents:
-            tmp_extents.remove(v)
-        elif isinstance(v, tir.IntImm) and v != 1:
-            raise ValueError(
-                f"buffer {buffer_region.buffer} region_extents[{i}] = {v}, extents[{i}] = {extents[i]}"
-            )
-
-    tmp_len = len(tmp_extents) - variable_extent_count
-    if tmp_len > 0:
-        # Otherwise, align extents from the last dimension, region_extents
-        # can only replace 1 with extents value, otherwise raise error
-        for i in range(len(extents)):
-            idx = len(region_extents) - len(extents) + i
-            if region_extents[idx] != extents[i]:
-                if region_extents[idx] == 1:
-                    region_extents[idx] = extents[i]
-                else:
-                    raise ValueError(
-                        f"buffer {buffer_region.buffer} region_extents[{idx}] = {region_extents[idx]}, extents[{i}] = {extents[i]}"
-                    )
+        extents
+    ), f"region_extents must be >= extents, region_extents = {region_extents}, extents = {extents}"
+
     return region(T.BufferLoad(buffer_region.buffer, mins), access_type, *region_extents)