[Mlir-commits] [mlir] [MLIR][XeGPU] Switch to 1D representation for SIMT code (PR #135116)

[Chao Chen]

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@@ -302,9 +270,33 @@ LogicalResult LoadNdOp::verify() {
   if (!isReadHintOrNone(getL3HintAttr()))
     return emitOpError("invalid l3_hint: ") << getL3HintAttr();
 
-  auto array_len = tdescTy.getArrayLength();
+  int tdescElems = tdescTy.getNumElements() * tdescTy.getArrayLength();
+  int valueElems = valueTy.getNumElements();
+
+  // If the result vector is 1D and has less elements than the tensor
+  // descriptor, it is supposed to be a SIMT op. The layout attribute in
+  // tensor_desc is not needed.
+  if (valueElems < tdescElems && valueTy.getRank() == 1) {
+    // SIMT mode doesn't need LayoutAttr.
+    if (tdescTy.getLayoutAttr())
+      return emitOpError()
+             << "TensorDesc doesn't need LayoutAttr for SIMT code";
+
+    // For SIMT code, the load is evenly distributed across all lanes in a
+    // subgroup. Since subgroup size is arch dependent, we only check even
+    // distribution here.
+    if (tdescElems % valueElems)
+      return emitOpError()
+             << "Result shape " << makeString(getShapeOf(valueTy))
+             << " is not a valid distribution for tensor descriptor "
+             << tdescTy;
+
+    return success();
+  }
+
+  // Check SIMD mode.
   // adjusted tensor descriptor shape tracks the expected shape of the result.
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chencha3 wrote:

fixed

https://github.com/llvm/llvm-project/pull/135116