[mlir][XeGPU] Add MemoryEffectsOpInterface for XeGPU memory related ops. (#125314)

`MemoryEffectsOpInterface` is needed for cleaning up the remaining
(dead) operations after XeGPU distribution into SIMT.

Author: charithaintc

mlir/include/mlir/Dialect/XeGPU/IR/XeGPUOps.td

@@ -276,7 +276,9 @@ def XeGPU_PrefetchNdOp : XeGPU_Op<"prefetch_nd", []> {
 }
 
 
-def XeGPU_LoadNdOp : XeGPU_Op<"load_nd", [AllElementTypesMatch<["value", "TensorDesc"]>]> {
+def XeGPU_LoadNdOp : XeGPU_Op<"load_nd", [
+  AllElementTypesMatch<["value", "TensorDesc"]>, MemoryEffects<[MemRead]>
+  ]> {
   let summary = "loads a n-D block from memory (represented by TensorDesc)"
                 "to registers (represented by vector)";
   let description = [{
@@ -327,7 +329,9 @@ def XeGPU_LoadNdOp : XeGPU_Op<"load_nd", [AllElementTypesMatch<["value", "Tensor
   let hasVerifier = 1;
 }
 
-def XeGPU_StoreNdOp : XeGPU_Op<"store_nd", [AllElementTypesMatch<["value", "TensorDesc"]>]> {
+def XeGPU_StoreNdOp : XeGPU_Op<"store_nd", [
+  AllElementTypesMatch<["value", "TensorDesc"]>, MemoryEffects<[MemWrite]>
+  ]> {
   let summary = "stores a n-D block register region back to memory, currently only supports 2D";
 
   let description = [{
@@ -548,7 +552,9 @@ def XeGPU_PrefetchOp : XeGPU_Op<"prefetch", []> {
   let hasVerifier = 1;
 }
 
-def XeGPU_LoadGatherOp : XeGPU_Op<"load", [AllElementTypesMatch<["value", "TensorDesc"]>]> {
+def XeGPU_LoadGatherOp : XeGPU_Op<"load", [
+  AllElementTypesMatch<["value", "TensorDesc"]>, MemoryEffects<[MemRead]>
+  ]> {
   let summary = "load a set of scattered data points from memory.";
 
   let description = [{ It (aka. load) load data per each work-item. The output
@@ -618,7 +624,9 @@ def XeGPU_LoadGatherOp : XeGPU_Op<"load", [AllElementTypesMatch<["value", "Tenso
   let hasVerifier = 1;
 }
 
-def XeGPU_StoreScatterOp : XeGPU_Op<"store", [AllElementTypesMatch<["value", "TensorDesc"]>]> {
+def XeGPU_StoreScatterOp : XeGPU_Op<"store", [
+  AllElementTypesMatch<["value", "TensorDesc"]>, MemoryEffects<[MemWrite]>
+  ]> {
   let summary = "store data to scattered memory locations.";
   let description = [{ It (aka. store) stores data to scattered memory locations. The value is
   typically a 1D vector. But when the chunk size of the TensorDesc is larger than 1, it will be